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1
Erdener, Timurkaynak, L. Rhoton Albert e Barry Margaret. "Microsurgical Anatomy and Operative Approaches to the Lateral Ventricles". Neurosurgery 19, n. 5 (1 novembre 1986): 685–723. http://dx.doi.org/10.1227/00006123-198611000-00001.
Testo completoAbstract (sommario):
Abstract The anatomy needed to plan microoperative approaches to the lateral ventricles was examined in 20 cadaveric cerebral hemispheres. The neural, arterial, and venous structures in the walls of the lateral ventricles and the relationship of the lateral ventricles to the third ventricle and basal cisterns were examined. The operative approaches to the lateral ventricle are reviewed.
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Shapoval, Lyudmila. "Atrioventricular junction symmetry in children with different anatomical variants of atrioventricular communication: echocardiographic parameters". Radiation Diagnostics, Radiation Therapy, n. 3 (2019): 15–23. http://dx.doi.org/10.37336/2707-0700-2019-3-1.
Testo completoAbstract (sommario):
Atrioventricular (AVC) communication is a group of congenital heart diseases with common atrioventricular connection. The symmetry of the connection and, as a result, anatomy and physiology of atrio-ventricular infl ow plays the key role in possibility of double-ventricle correction in this anomaly. Nowadays there is tendency to mix new concepts with described parameters that characterize AVC in one whole guidelines. The ultimate pathway has to be the one that minimizes morbidity and mortality outcomes. In the article author present the correlation between main cardiac echocardiography measurements, that characterize the symmetry of atrioventriculat connection (atrioventricular valves indexes, left ventricle inflow index, inflow angle between left and right ventricles) and their correlation with size of common atrio-ventricular valve and ventricle’s size. Key words: unbalanced atrioventricular communication, atrioventricular valve index, left ventricular flow index, inflow angle between right and left ventricles, ventricular cavity index.
3
Pipitone, Salvatore. "Superoinferior ventricles with superior left ventricle". Journal of Cardiovascular Medicine 13, n. 9 (settembre 2012): 607–13. http://dx.doi.org/10.2459/jcm.0b013e3283515bf6.
Testo completo
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Kurtcuoglu, Vartan, Dimos Poulikakos e Yiannis Ventikos. "Computational Modeling of the Mechanical Behavior of the Cerebrospinal Fluid System". Journal of Biomechanical Engineering 127, n. 2 (6 novembre 2004): 264–69. http://dx.doi.org/10.1115/1.1865191.
Testo completoAbstract (sommario):
A computational fluid dynamics (CFD) model of the cerebrospinal fluid system was constructed based on a simplified geometry of the brain ventricles and their connecting pathways. The flow is driven by a prescribed sinusoidal motion of the third ventricle lateral walls, with all other boundaries being rigid. The pressure propagation between the third and lateral ventricles was examined and compared to data obtained from a similar geometry with a stenosed aqueduct. It could be shown that the pressure amplitude in the lateral ventricles increases in the presence of aqueduct stenosis. No difference in phase shift between the motion of the third ventricle walls and the pressure in the lateral ventricles because of the aqueduct stenosis could be observed. It is deduced that CFD can be used to analyze the pressure propagation and its phase shift relative to the ventricle wall motion. It is further deduced that only models that take into account the coupling between ventricles, which feature a representation of the original geometry that is as accurate as possible and which represent the ventricle boundary motion realistically, should be used to make quantitative statements on flow and pressure in the ventricular space.
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Bernal-Ramirez, Judith, Magda C. Díaz-Vesga, Matias Talamilla, Andrea Méndez, Clara Quiroga, Javier A. Garza-Cervantes, Anay Lázaro-Alfaro et al. "Exploring Functional Differences between the Right and Left Ventricles to Better Understand Right Ventricular Dysfunction". Oxidative Medicine and Cellular Longevity 2021 (28 agosto 2021): 1–21. http://dx.doi.org/10.1155/2021/9993060.
Testo completoAbstract (sommario):
The right and left ventricles have traditionally been studied as individual entities. Furthermore, modifications found in diseased left ventricles are assumed to influence on right ventricle alterations, but the connection is poorly understood. In this review, we describe the differences between ventricles under physiological and pathological conditions. Understanding the mechanisms that differentiate both ventricles would facilitate a more effective use of therapeutics and broaden our knowledge of right ventricle (RV) dysfunction. RV failure is the strongest predictor of mortality in pulmonary arterial hypertension, but at present, there are no definitive therapies directly targeting RV failure. We further explore the current state of drugs and molecules that improve RV failure in experimental therapeutics and clinical trials to treat pulmonary arterial hypertension and provide evidence of their potential benefits in heart failure.
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Ogiwara, Hideki, e Nobuhito Morota. "Flexible endoscopy for management of intraventricular brain tumors in patients with small ventricles". Journal of Neurosurgery: Pediatrics 14, n. 5 (novembre 2014): 490–94. http://dx.doi.org/10.3171/2014.7.peds13648.
Testo completoAbstract (sommario):
Object Endoscopic surgery is generally withheld in patients with small ventricles due to difficulties in ventricular cannulation and intraventricular manipulation. The effectiveness of flexible endoscopy for management of intraventricular brain tumors in patients with small ventricles was evaluated. Methods Forty-five patients who underwent endoscopic surgery with a flexible endoscope for intraventricular brain tumors were divided into small-ventricle and ventriculomegaly groups according to the frontal and occipital horn ratio (FOR). Retrospective review of these cases was performed and achievement of surgical goals and morbidity were assessed. Results Among the 45 patients, there were 14 with small ventricles and 31 with ventriculomegaly. In the smallventricle group, targeted tumors were located in the suprasellar region in 12 patients and in the pineal region in 2. In the ventriculomegaly group, tumors were located in the pineal region in 15 patients, in the suprasellar region in 9, in the lateral ventricle in 4, in the midbrain in 2, and in the fourth ventricle in 1. In the small-ventricle group, ventricular cannulation was successful and the surgical goals were accomplished in all patients. In ventriculomegaly group, sampling of the tumor was not diagnostic due to intraoperative hemorrhage in 1 patient. There were no significant differences in the rate of achieving the surgical goals or the morbidity between the 2 groups. Conclusions Endoscopic surgery using a flexible endoscope is useful for management of intraventricular brain tumors in patients with small ventricles. A flexible endoscope allows excellent maneuverability in introducing the device into the lateral ventricle and manipulating through small ventricles.
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Sethi, R., K. S. Dhalla, R. E. Beamish e N. S. Dhalla. "Differential changes in left and right ventricular adenylyl cyclase activities in congestive heart failure". American Journal of Physiology-Heart and Circulatory Physiology 272, n. 2 (1 febbraio 1997): H884—H893. http://dx.doi.org/10.1152/ajpheart.1997.272.2.h884.
Testo completoAbstract (sommario):
The status of beta-adrenergic receptors and adenylyl cyclase in crude membranes from both left and right ventricles was examined when the left coronary artery in rats was occluded for 4, 8, and 16 wk. The adenylyl cyclase activity in the presence of isoproterenol was decreased in the uninfarcted (viable) left ventricle and increased in the right ventricle subsequent to myocardial infarction. The density of beta1-adrenergic receptors, unlike beta2-receptors, was reduced in the left ventricle, whereas no change in the characteristics of beta1- and beta2-adrenergic receptors was seen in the right ventricle. The catalytic activity of adenylyl cyclase was depressed in the viable left ventricle but was unchanged in the right ventricle. In comparison to sham controls, the basal, as well as NaF-, forskolin-, and 5'-guanylyl imidodiphosphate [Gpp(NH)p]-stimulated adenylyl cyclase activities were decreased in the left ventricle and increased in the right ventricle of the experimental animals. Opposite alterations in the adenylyl cyclase activities in left and right ventricles from infarcted animals were also seen when two types of purified sarcolemmal preparations were employed. These changes in adenylyl cyclase activities in the left and right ventricles were dependent on the degree of heart failure. Furthermore, adenosine 3',5'-cyclic monophosphate contents were higher in the right ventricle and lower in the left ventricle from infarcted animals injected with saline, isoproterenol, or forskolin in comparison to the controls. The results suggest differential changes in the viable left and right ventricles with respect to adenylyl cyclase activities during the development of congestive heart failure due to myocardial infarction.
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Anderson, Robert H., Timothy J. Mohun e Antoon F. M. Moorman. "What is a ventricle?" Cardiology in the Young 21, S2 (13 dicembre 2011): 14–22. http://dx.doi.org/10.1017/s1047951111001387.
Testo completoAbstract (sommario):
AbstractOn the basis of both developmental and morphological evidence, we would suggest that a ventricle is best defined as any chamber within the ventricular mass possessing an apical trabecular component. Such ventricles can be of right or left morphology, and always coexist. The ventricles are normally formed when possessing all three of the inlet, apical trabecular, and outlet components, but incomplete when lacking one or both of the inlet and outlet components. Ventricles that are incomplete because of lack of the inlet component are always hypoplastic, with incomplete right ventricles being positioned antero-superiorly within the ventricular mass, and incomplete left ventricles located postero-inferiorly. Patients having such incomplete ventricles because of the lack of the inlet component have functionally univentricular hearts, although the functionally univentricular arrangement can also be produced in the setting of normally constituted but hypertrophied ventricles. Full analysis of ventricular morphology, therefore, requires attention not only to component make-up, but also size.
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Nakazawa, Ken, Yutaka Kusuya e Koki Shigenobu. "Developmental increase in the inotropic and cyclic AMP response to isoproterenol in embryonic and newly hatched chicks". Canadian Journal of Physiology and Pharmacology 67, n. 9 (1 settembre 1989): 1109–11. http://dx.doi.org/10.1139/y89-176.
Testo completoAbstract (sommario):
The cyclic adenosine 3′,5′-monophosphate (cyclic AMP) levels of ventricles isolated from 15- to 20-day-old chick embryos and 0- to 3-day-old hatched chicks were compared to clarify the mechanism underlying the change in sensitivity to isoproterenol during perinatal developmental stages when the functional sympathetic innervation has been completely achieved. Isoproterenol produced a positive inotropic effect on ventricles isolated from both embryonic and hatched chicks, but the ventricles from the hatched chicks were more sensitive. At both developmental stages sotalol was an equipotent antagonist of isoproterenol. 3-Isobutyl-1-methylxanthine (IBMX) produced an increment in the contractile force of the ventricles at both stages, but the ventricles from the hatched chicks responded to lower doses of IBMX. The reactivity to isoproterenol in increasing cyclic AMP level was significantly higher in the hatched ventricles than in the embryonic ventricles. The results suggest that the different sensitivities to isoproterenol between embryonic and newly hatched chick ventricles may be due to some changes in the process for cyclic AMP production.Key words: chick ventricle, development, β-adrenergic sensitivity, cyclic AMP.
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Iliev, Alexandar A., Georgi N. Kotov, Boycho V. Landzhov, Lazar S. Jelev, Iva N. Dimitrova e Dimka V. Hinova-Palova. "A Comparative Quantitative Analysis of the Postnatal Changes in the Myocardium of the Left and Right Ventricles in Rats". Folia Medica 60, n. 2 (1 giugno 2018): 226–33. http://dx.doi.org/10.1515/folmed-2017-0089.
Testo completoAbstract (sommario):
Abstract Background: The growth of the heart during the foetal and early postnatal development takes places mainly due to hyperplasia. The late postnatal development is characterised by cardiomyocytic hypertrophy in response to normal physiological mechanisms and increased load. To study the cell size most authors measure the diameter either directly or indirectly. Aim: The aim of the present study was to make a comparative quantitative analysis of the postnatal changes observed in the left and right ventricles in rat by evaluating the changes in three morphometric parameters – thickness of the free wall, transverse section of the cardiomyocytes and cardiomyocytic density in the left ventricle and right ventricle. Materials and methods: In the present study, we used histological material from the hearts of 15 male Wistar rats, distributed in five groups aged 2 weeks, 1 month, 3 months, 6 months and 12 months, respectively. Results: In both ventricles, the wall thickness and the transverse section of the cardiomyocytes increased with age, while the cardiomyocytic density decreased. Changes were identical in both ventricles; however, they were more dynamic and pronounced in the left ventricle. Conclusions: The studied morphometric parameters reveal that age-related hypertrophy and the gradual loss of cardiac muscle cells take place in both ventricles but have a more dynamic pattern of progression in the left ventricle as compared with the right ventricle.
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Chen, Li-Jun, Zhi-Rong Tong, Qian Wang, Yu-Qi Zhang e Jin-Long Liu. "Feasibility of Computational Fluid Dynamics for Evaluating the Intraventricular Hemodynamics in Single Right Ventricle Based on Echocardiographic Images". BioMed Research International 2018 (2018): 1–11. http://dx.doi.org/10.1155/2018/1042038.
Testo completoAbstract (sommario):
This study introduced a combined computational fluid dynamics (CFD) and echocardiography methodology to simulate blood flow in the single right ventricle (SRV) and normal ventricles to study the intraventricular flow. Derived from echocardiographic image loops, CFD-based three-dimensional (3D) flow models of normal subject’s left ventricle (LV) and right ventricle (RV) and SRV with and without heart failure at three characteristic diastolic statuses were reconstructed. The CFD derived morphological and functional measurements in normal ventricles and the SRV were validated with echocardiography. The vortex in the normal ventricles and the SRV were studied. The morphological and functional measurements derived from CFD modeling and echocardiography were comparable, and both methods demonstrated the larger volume and higher spherical index in the SRV, in particular the SRV with heart failure. All the vortices in the SRV were smaller than those in the normal control subject’s LV and RV, notably with heart failure. Unlike normal LV and RV, no vortex ring was observed in the SRV. Echocardiography-based CFD demonstrated the feasibility of quantifying ventricular morphology and function; in addition, CFD can detect the abnormal flow pattern (smaller or obliterated vortices) in the SRV when compared with normal ventricles.
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Helwan, Abdulkader, e Dilber Uzun Ozsahin. "Sliding Window Based Machine Learning System for the Left Ventricle Localization in MR Cardiac Images". Applied Computational Intelligence and Soft Computing 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/3048181.
Testo completoAbstract (sommario):
The most commonly encountered problem in vision systems includes its capability to suffice for different scenes containing the object of interest to be detected. Generally, the different backgrounds in which the objects of interest are contained significantly dwindle the performance of vision systems. In this work, we design a sliding windows machine learning system for the recognition and detection of left ventricles in MR cardiac images. We leverage on the capability of artificial neural networks to cope with some of the inevitable scene constraints encountered in medical objects detection tasks. We train a backpropagation neural network on samples of left and nonleft ventricles. We reformulate the left ventricles detection task as a machine learning problem and employ an intelligent system (backpropagation neural network) to achieve the detection task. We treat the left ventricle detection problem as binary classification tasks by assigning collected left ventricle samples as one class, and random (nonleft ventricles) objects are the other class. The trained backpropagation neural network is validated to possess a good generalization power by simulating it with a test set. A recognition rate of 100% and 88% is achieved on the training and test set, respectively. The trained backpropagation neural network is used to determine if the sampled region in a target image contains a left ventricle or not. Lastly, we show the effectiveness of the proposed system by comparing the manual detection of left ventricles drawn by medical experts and the automatic detection by the trained network.
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Przyborowska, Paulina, Zbigniew Adamiak e Yauheni Zhalniarovich. "Quantification of cerebral lateral ventricular volume in cats by low- and high-field MRI". Journal of Feline Medicine and Surgery 19, n. 10 (10 novembre 2016): 1080–86. http://dx.doi.org/10.1177/1098612x16676434.
Testo completoAbstract (sommario):
Objectives The aim of this study was to evaluate variations in lateral ventricles in the examined feline population with the use of quantitative analysis methods to determine whether sex or body weight influenced the size of the ventricles, and to identify any significant differences in the results of low- and high-field MRI. Methods Twenty healthy European Shorthair cats, aged 1–3 years, with body weights ranging from 2.85–4.35 kg, were studied. MRI of brain structures was performed in a low- and a high-field MRI system. The height of the brain and lateral ventricles at the level of the interthalamic adhesion, and volume of the lateral ventricles were determined in T2-weighted images in the transverse plane. The degree of symmetry of lateral ventricles was analysed based on the ratio of right to left ventricular volume. The measured parameters were processed statistically to determine whether sex and body weight were significantly correlated with variations in ventricular anatomy. The results of low- and high-field MRI were analysed to evaluate for any significant differences. Results The average brain height was determined to be 27.79 mm, and the average height of the left and right ventricles were 2.98 mm and 2.89 mm, respectively. The average ventricle/brain height ratio was 10.61%. The average volume of the left ventricle was 134.12 mm3 and the right ventricle was 130.49 mm3. Moderately enlarged ventricles were observed in two cats. Moderate ventricular asymmetry was described in four cats. Sex and body weight had no significant effect on the evaluated parameters. The differences in the results of low- and high-field MRI were not statistically significant. Conclusions and relevance This study has determined reference intervals for ventricular volume in a population of European Shorthair cats without brain disease, which will facilitate the interpretation of MRI images and the characterisation of brain abnormalities in cats with neurological disease. Further research involving larger animal populations, including other breeds, is required to compare the measured parameters between breeds and to determine reference values for other breeds.
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Shimura, Daisuke, Gaku Nakai, Qibin Jiao, Kota Osanai, Kasumi Kashikura, Keiko Endo, Tomoyoshi Soga, Nobuhito Goda e Susumu Minamisawa. "Metabolomic profiling analysis reveals chamber-dependent metabolite patterns in the mouse heart". American Journal of Physiology-Heart and Circulatory Physiology 305, n. 4 (15 agosto 2013): H494—H505. http://dx.doi.org/10.1152/ajpheart.00867.2012.
Testo completoAbstract (sommario):
Energy of the cardiac muscle largely depends on fatty acid oxidation. It is known that the atrium and ventricle have chamber-specific functions, structures, gene expressions, and pathologies. The left ventricle works as a high-pressure chamber to pump blood toward the body, and its muscle wall is thicker than those of the other chambers, suggesting that energy utilization in each of the chambers should be different. However, a chamber-specific pattern of metabolism remains incompletely understood. Recently, innovative techniques have enabled the comprehensive analysis of metabolites. Therefore, we aimed to clarify differences in metabolic patterns among the chambers. Male C57BL6 mice at 6 wk old were subject to a comprehensive measurement of metabolites in the atria and ventricles by capillary electrophoresis and mass spectrometry. We found that overall metabolic profiles, including nucleotides and amino acids, were similar between the right and left ventricles. On the other hand, the atria exhibited a distinct metabolic pattern from those of the ventricles. Importantly, the high-energy phosphate pool (the total concentration of ATP, ADP, and AMP) was higher in both ventricles. In addition, the levels of lactate, acetyl CoA, and tricarboxylic acid cycle contents were higher in the ventricles. Accordingly, the activities and/or expression levels of key enzymes were higher in the ventricles to produce more energy. The present study provides a basis for understanding the chamber-specific metabolism underlining pathophysiology in the heart.
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Togi, Kiyonori, Takahiro Kawamoto, Ryoko Yamauchi, Yoshinori Yoshida, Toru Kita e Makoto Tanaka. "Role of Hand1/eHAND in the Dorso-Ventral Patterning and Interventricular Septum Formation in the Embryonic Heart". Molecular and Cellular Biology 24, n. 11 (1 giugno 2004): 4627–35. http://dx.doi.org/10.1128/mcb.24.11.4627-4635.2004.
Testo completoAbstract (sommario):
ABSTRACT Molecular mechanisms for the dorso-ventral patterning and interventricular septum formation in the embryonic heart are unknown. To investigate a role of Hand1/eHAND in cardiac chamber formation, we generated Hand1/eHAND knock-in mice where Hand1/eHAND cDNA was placed under the control of the MLC2V promoter. In Hand1/eHAND knock-in mice, the outer curvature of the right and left ventricles expanded more markedly. Moreover, there was no interventricular groove or septum formation, although molecularly, Hand1/eHAND knock-in hearts had two ventricles. However, the morphology of the inner curvature of the ventricles, the atrioventricular canal, and the outflow tract was not affected by Hand1/eHAND expression. Furthermore, expression of Hand1/eHAND in the whole ventricles altered the expression patterns of Chisel, ANF, and Hand2/dHAND but did not affect Tbx5 expression. In contrast, the interventricular septum formed normally in transgenic embryos overexpressing Hand1/eHAND in the right ventricle but not in the boundary region. These results suggested that Hand1/eHAND is involved in expansion of the ventricular walls and that absence of Hand1/eHAND expression in the boundary region between the right and left ventricles may be critical in the proper formation of the interventricular groove and septum. Furthermore, Hand1/eHAND is not a master regulatory gene that specifies the left ventricle myocyte lineage but may control the dorso-ventral patterning in concert with additional genes.
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Bankier, Robert G. "Third Ventricle Size and Dementia in Schizophrenia". British Journal of Psychiatry 147, n. 3 (settembre 1985): 241–45. http://dx.doi.org/10.1192/bjp.147.3.241.
Testo completoAbstract (sommario):
Using an ultrasound technique, the widths of the third ventricle in a group of normal subjects was compared with groups of chronic schizophrenics and acutely ill schizophrenics. While the chronic patients showed a significantly wider ventricle (p < 0.5) from the other two groups, only 14% of the chronic patients had a third ventricle greater than the accepted normal maximum of 8 mm. Neuropsychological tests confirmed organic brain impairment in both chronic and acutely ill patients but there was no significant difference between chronic patients with large ventricles and those with normal size ventricles. This suggests that third ventricle size is not part of the schizophrenic disease process and is not related to the dementia seen in the late stages of the illness.
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Godkov, I. M., e V. G. Dashyan. "ENDOSCOPIC INTRAVENTRICULAR HEMORRHAGE REMOVAL: CLINICAL OBSERVATION AND TECHNICAL FEATURES". Russian journal of neurosurgery 21, n. 2 (16 giugno 2019): 45–52. http://dx.doi.org/10.17650/1683-3295-2019-21-2-45-52.
Testo completoAbstract (sommario):
The study objective is to describe a successful endoscopic therapy for a patient with hypertensive ventricular hemorrhage complicated by occlusive third ventricular hydrocephalus. Materials and methods. A 71-year-old patient with hypertensive hemorrhage into the III and IV ventricles, complicated by non-communicating hydrocephalus, was brought to hospital on the 1st day of the disease onset. Non-communicating hydrocephalus was accompanied by clinical signs of decompensation, depressed level of consciousness up to moderate coma (Glasgow Coma Scale score of 7). Specialists performed emergency endoscopic aspiration of blood clots from the III and IV ventricles and third ventriculostomy. Results. Endoscopically it was possible to remove the clots from the third ventricle and through the cerebral aqueduct from the fourth ventricle. Resuscitation and intensive care measures resulted in a favorable outcome: the patient was released with a moderate neurological deficit – left oculomotor nerve dysfunction. After 4 months, the patient required a ventriculoperitoneal shunt due to disresponsive form of hydrocephalus. Conclusion. Endoscopic aspiration allows removing hematomas from the third and fourth ventricles via the lateral ventricle effectively and safely.
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Eichele, Gregor, Eberhard Bodenschatz, Zuzana Ditte, Ann-Kathrin Günther, Shoba Kapoor, Yong Wang e Christian Westendorf. "Cilia-driven flows in the brain third ventricle". Philosophical Transactions of the Royal Society B: Biological Sciences 375, n. 1792 (30 dicembre 2019): 20190154. http://dx.doi.org/10.1098/rstb.2019.0154.
Testo completoAbstract (sommario):
The brain ventricles are interconnected, elaborate cavities that traverse the brain. They are filled with cerebrospinal fluid (CSF) that is, to a large part, produced by the choroid plexus, a secretory epithelium that reaches into the ventricles. CSF is rich in cytokines, growth factors and extracellular vesicles that glide along the walls of ventricles, powered by bundles of motile cilia that coat the ventricular wall. We review the cellular and biochemical properties of the ventral part of the third ventricle that is surrounded by the hypothalamus. In particular, we consider the recently discovered intricate network of cilia-driven flows that characterize this ventricle and discuss the potential physiological significance of this flow for the directional transport of CSF signals to cellular targets located either within the third ventricle or in the adjacent hypothalamic brain parenchyma. Cilia-driven streams of signalling molecules offer an exciting perspective on how fluid-borne signals are dynamically transmitted in the brain. This article is part of the Theo Murphy meeting issue ‘Unity and diversity of cilia in locomotion and transport’.
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Preedy, V. R., D. M. Smith, N. F. Kearney e P. H. Sugden. "Regional variation and differential sensitivity of rat heart protein synthesis in vivo and in vitro". Biochemical Journal 225, n. 2 (15 gennaio 1985): 487–92. http://dx.doi.org/10.1042/bj2250487.
Testo completoAbstract (sommario):
In vivo, fractional rates of protein synthesis in atrial muscle of hearts taken from fed rats were 70% greater than in ventricular muscle. After 3 days starvation, atrial protein synthesis is inhibited, but the inhibition is less than in ventricles. A crude subcellular fractionation of the aqueous homogenates by centrifugation at 32000g showed that the supernatant and precipitate proteins were synthesized at the same rate in the ventricles. The fractional rates of protein synthesis and RNA/protein ratios in the right ventricle were 10% greater than in the left ventricle. Protein synthesis in both of these regions was inhibited equally by starvation. In vitro, rates of protein synthesis in atria and ventricles of anterogradely perfused rat hearts were stimulated by saturating insulin concentrations and were inhibited by starvation, but the effects in atria were smaller than in ventricles. Rates of protein synthesis in atria in vitro were 80-95% of rates in vivo. The heart therefore shows considerable regional variation in rates of protein synthesis in vivo and in vitro, and the sensitivity of protein synthesis in the various regions to interventions such as insulin and starvation differs.
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Veteskova, J., M. Obsivan, Z. Kmecova, M. Radik, J. Srankova, E. Malikova, J. Klimas e P. Krenek. "SDF-1 and its receptor in the ventricles of rat with monocrotaline-induced pulmonary hypertension". European Pharmaceutical Journal 65, n. 2 (1 novembre 2018): 23–26. http://dx.doi.org/10.2478/afpuc-2018-0004.
Testo completoAbstract (sommario):
Abstract Aim: Chemokine stromal cell derived factor-1 (SDF-1) plays an important role in many processes such as apoptosis, proliferation, migration and angiogenesis, and these effects are mediated mostly by the receptor CXCR4. The aim of this study was to determine the expression of SDF-1 and CXCR4 in the ventricles of rats with monocrotaline-induced pulmonary hypertension. Methods: 10–12 weeks old male Wistar rats were injected with monocrotaline (s. c., 60mg/kg; MON) or vehicle (CON). Rats were sacrificed 1 week (1W-MON, 1W-CON), 2 weeks (2W-MON, 2W-CON) and 4 weeks after monocrotaline administration (4W-MON, 4W-CON). Gene expression of SDF-1 and CXCR4 was determined by qRT-PCR. Results: We observed a decrease in the SDF-1 expression on mRNA level in the right ventricle in 2W-MON and 4W-MON rats without any changes in the left ventricles and a decrease in CXCR4 expression in 1W-MON in both ventricles with an increase of CXCR4 expression in 4W-MON in the left ventricle (*P ˂ 0.05). Conclusion: SDF-1/CXCR4 axis is affected in both ventricles of rats with monocrotaline model of pulmonary hypertension.
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Fannon, Dominic, Lakshika Tennakoon, Alex Sumich, Seamus O'Ceallaigh, Victor Doku, Xavier Chitnis, Jennifer Lowe, William Soni e Tonmoy Sharma. "Third ventricle enlargement and developmental delay in first-episode psychosis: preliminary findings". British Journal of Psychiatry 177, n. 4 (ottobre 2000): 354–59. http://dx.doi.org/10.1192/bjp.177.4.354.
Testo completoAbstract (sommario):
BackgroundThird rather than lateral ventriculomegaly may be a more specific finding in psychosis. The relevance of ventricular abnormality remains unclear.AimsTo investigate the developmental correlates of ventricular enlargement.MethodInformation on childhood development and magnetic resonance images in 1.5-mm contiguous sections were collected on 21 patients experiencing a first episode of psychosis.ResultsPatients (n=21) had significantly less whole brain volume and enlarged third and lateral ventricles compared to controls (n=25). Third ventricle (r=0.48, P < 0.03) and lateral ventricle (r=0.65, P < 0.01) volumes correlated with developmental score. Patients with developmental delay had significantly larger third and lateral ventricles than those without.ConclusionsEnlargement of both third and lateral ventricles is found in first-episode psychosis and is related to developmental delay in childhood. Insult to periventricular areas is relevant to the neurobiology of the disease. These findings support the view that schizophrenia involves disturbance of neurodevelopmental processes in some patients.
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Mampalam, Thomas. "Ventricles". JAMA 318, n. 2 (11 luglio 2017): 203. http://dx.doi.org/10.1001/jama.2017.1778.
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Eller, Theodore W., e Joseph F. Pasternak. "Isolated ventricles following intraventricular hemorrhage". Journal of Neurosurgery 62, n. 3 (marzo 1985): 357–62. http://dx.doi.org/10.3171/jns.1985.62.3.0357.
Testo completoAbstract (sommario):
✓ Panventricular enlargement often follows intraventricular hemorrhage in the premature neonate. During a recent 12-month period, the authors identified five infants who required shunting because of symptomatic post-hemorrhagic hydrocephalus, which was progressive despite serial lumbar punctures and the use of indwelling subcutaneous ventricular reservoirs. In the first 6 months following placement of the initial shunt, four of the infants required an additional shunt for isolated ventricles. Two children had isolation of the lateral ventricles and required bilateral shunts. Two other children had isolation of the fourth ventricle from the lateral ventricular system and required posterior fossa shunts. All of the children were treated successfully using multiple shunts. In all cases, progressive dilation of the isolated ventricle was unaccompanied by the usual clinical signs of shunt malfunction. It appears that isolated ventricular systems are common following post-hemorrhagic hydrocephalus and these children must be followed closely with ultrasound and computerized tomography scanning.
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Sinha, Manisha B., Suchitra Kishore Somkuwar, Dharmendra Kumar e D. K. Sharma. "Anatomical variations of papillary muscles in human cadaveric hearts of Chhattisgarh, India". Indian Journal of Clinical Anatomy and Physiology 7, n. 4 (15 gennaio 2021): 374–80. http://dx.doi.org/10.18231/j.ijcap.2020.078.
Testo completoAbstract (sommario):
In both ventricles of the heart papillary muscles play important role for proper cardiac valvular function of heart. The present study was done to analyse the papillary muscles of heart with respect to the variations in their number, length, shape, position and pattern in both ventricles. Forty well preserved cadaveric human hearts were used for the study. The variations in the papillary muscles of both right and left ventricles were categorized, documented and photographed. In the right ventricle, authors observed 31.42% anterior, 34.3% posterior and 34.3% septal papillary muscles, and in the left ventricle, 41.7% anterior and 58.3% posterior papillary muscles. Classical papillary muscles were observed in 64.3% heart specimens in right ventricle and 55% in left ventricle. Authors found conical, pyramidal and broad apexed papillary muscles in 44.3%, 51.4% and 4.3% heart specimens respectively in right ventricle, whereas in left ventricle the corresponding values were 33.3%, 30% and 36.7%. Separate bases and fused apex pattern was observed in 24.3%, single base and divided apex in 55.7% heart specimens in right ventricle and in left ventricle in 45% and 43.3% heart specimens respectively. The length of anterior, posterior and septal papillary muscle in right ventricle was 1.27±0.45, 1.36±0.52, 0.92±0.54 cm respectively whereas in left ventricle, the mean length of anterior and posterior papillary muscles was 2.13±0.44 and 1.76±0.46 cm. In right ventricle mean thickness was 1.17±0.31cm whereas in left ventricle it was 2.16±0.32 cm. The papillary muscles has complex and variable anatomy. Knowledge of this variation to the cardiac surgeons during reparative surgical procedures conducted for mitral/ tricuspid valve replacement is of utmost importance to prevent untoward event.
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Browne, Vaughn A., Virginia M. Stiffel, William J. Pearce, Lawrence D. Longo e Raymond D. Gilbert. "Cardiac β-adrenergic receptor function in fetal sheep exposed to long-term high-altitude hypoxemia". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 273, n. 6 (1 dicembre 1997): R2022—R2031. http://dx.doi.org/10.1152/ajpregu.1997.273.6.r2022.
Testo completoAbstract (sommario):
In this study, we hypothesized that a reduction in β-adrenergic receptor number or a decrease in functional coupling of the receptor to the adenylate cyclase system may be responsible for the blunted inotropic response to isoproterenol observed in fetal sheep exposed to high altitude (3,820 m) from 30 to 138–142 days gestation. We measured the contractile response to increasing doses of isoproterenol and forskolin in papillary muscles from both ventricles, estimated β-adrenergic receptor density (Bmax) and ligand affinity ( K d) using [125I]iodocyanopindolol, and measured adenosine 3′,5′-cyclic monophosphate (cAMP) levels before and after maximally stimulating doses of isoproterenol and forskolin. Left ventricular wet weight was unchanged, but right ventricular weight was 20% lower than controls. At the highest concentration of isoproterenol (10 μM), maximum active tension was 32 and 20% lower than controls in hypoxemic left and right ventricles, respectively. The contractile response to forskolin was severely attenuated in both hypoxemic ventricles. Bmax was unchanged in the left ventricle, but increased by 55% in the hypoxemic right ventricle. K d was not different from controls in either ventricle. Basal cAMP levels were not different from controls, but isoproterenol-stimulated and forskolin-stimulated cAMP levels were 1.4- to 2-fold higher than controls in both hypoxemic ventricles. The results suggest mechanisms downstream from cAMP in the β-adrenergic receptor pathway are responsible for the attenuated contractile responses to isoproterenol.
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Reinitz, László Z., Gábor Bajzik, Rita Garamvölgyi, Bianka Benedek, Örs Petneházy, András Lassó, Zsolt Abonyi-Tóth, Borbála Lőrincz e Péter Sótonyi. "Linear relationship found by magnetic resonance imaging between cerebrospinal fluid volume and body weight in dogs". Acta Veterinaria Hungarica 65, n. 1 (marzo 2017): 1–12. http://dx.doi.org/10.1556/004.2017.001.
Testo completoAbstract (sommario):
Despite numerous studies on cerebrospinal fluid (CSF) and its importance during hydrocephalus or myelography, no reliable values exist about its overall volume in dogs. In this study, our aim was to measure the intracranial (IC) volume of CSF in dogs and assess its possible relationship with body size and the symmetry of the lateral ventricles. We ran a 3D magnetic resonance imaging (MRI) sequence on the central nervous system of 12 healthy, male mongrel dogs between 3–5 years of age and 7.5–35.0 kg body weight. A validated semiautomatic segmentation protocol was implemented to segment the CSF and measure its volume. Values for the volume of the ventricular compartment were between 0.97 and 2.94 ml, with 62.1 ± 11.7% in the lateral ventricles, 17.6 ± 4.9% in the third ventricle, 4.9 ± 1.6% in the aqueductus mesencephali and 15.5 ± 6.6% in the fourth ventricle. In 11 cases a significant asymmetry was found between the lateral ventricles. The results suggest that it may be normal for a dog to have one of the lateral ventricles 1.5 times larger than the other. The correlation between body weight and CSF volume was linear, indicating that the current dosage protocols for myelography, based on a hypothetical proportional relationship with body weight, may have to be revised.
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Babicsak, Viviam R., Adriana V. Klein, Miriam H. Tsunemi e Luiz C. Vulcano. "Age-related changes of the cerebral ventricles of healthy domestic cats". Pesquisa Veterinária Brasileira 38, n. 10 (ottobre 2018): 1935–41. http://dx.doi.org/10.1590/1678-5150-pvb-5208.
Testo completoAbstract (sommario):
ABSTRACT: This study aimed to determine age-related changes of the cerebral ventricles of healthy non-brachycephalic domestic cats by the acquisition of brain MRI images of 12 adult (1 to 6 years), 11 mature (7 to11 years) and 10 geriatric (12 years or more) cats. Our hypothesis is that the cerebral ventricular system of cats expands with increasing age. The possibility of the evidence of the olfactory bulb cavities and temporal horns of the lateral ventricles were evaluated in this study. Volumes of the olfactory bulb cavities, lateral ventricles (including the temporal horns), third ventricle, mesencephalic aqueduct and fourth ventricle were measured and corrected for the intracranial volume. Significant differences were found between the adult and mature groups in relation to the geriatric one for the variable related to the evidence of the temporal ventricular horns, which were most frequently visualized in geriatric cats. Percentage of the right lateral and third ventricles volume by intracranial volume were significantly higher in geriatric cats compared to the adults. The results of this study demonstrate that ventricular dilation tends to occur with advancing age in cats, as well as the increase in the frequency of the temporal ventricular horn evidence, as had been indicated in the hypothesis of the study.
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Rose, Jochen, Antonis A. Armoundas, Yanli Tian, Deborah DiSilvestre, Miroslava Burysek, Victoria Halperin, Brian O'Rourke, David A. Kass, Eduardo Marbán e Gordon F. Tomaselli. "Molecular correlates of altered expression of potassium currents in failing rabbit myocardium". American Journal of Physiology-Heart and Circulatory Physiology 288, n. 5 (maggio 2005): H2077—H2087. http://dx.doi.org/10.1152/ajpheart.00526.2003.
Testo completoAbstract (sommario):
Action potential (AP) prolongation is a hallmark of failing myocardium. Functional downregulation of K currents is a prominent feature of cells isolated from failing ventricles. The detailed changes in K current expression differ depending on the species, the region of the heart, and the mechanism of induction of heart failure. We used complementary approaches to study K current downregulation in pacing tachycardia-induced heart failure in the rabbit. The AP duration (APD) at 90% repolarization was significantly longer in cells isolated from failing hearts compared with controls (539 ± 162 failing vs. 394 ± 114 control, P < 0.05). The major K currents in the rabbit heart, inward rectifier potassium current ( IK1), transient outward ( Ito), and delayed rectifier current ( IK) were functionally downregulated in cells isolated from failing ventricles. The mRNA levels of Kv4.2, Kv1.4, KChIP2, and Kir2.1 were significantly downregulated, whereas the Kv4.3, Erg, KvLQT1, and minK were unaltered in the failing ventricles compared with the control left ventricles. Significant downregulation in the long splice variant of Kv4.3, but not in the total Kv4.3, Kv4.2, and KChIP2 immunoreactive protein, was observed in cells isolated from the failing ventricle with no change in Kv1.4, KvLQT1, and in Kir2.1 immunoreactive protein levels. Multiple cellular and molecular mechanisms underlie the downregulation of K currents in the failing rabbit ventricle.
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Fujimoto, K., H. Yasue, K. Nakao, H. Yamamoto, Y. Hitoshi, M. Jougasaki, K. Okumura, H. Ogawa, K. Takatsu e E. Miyamoto. "Novel monoclonal antibodies specific for human cardiac myosin light-chain 1: useful tools for analysis of normal and pathological hearts." Journal of Histochemistry & Cytochemistry 41, n. 1 (gennaio 1993): 35–42. http://dx.doi.org/10.1177/41.1.8417110.
Testo completoAbstract (sommario):
To investigate the developmental, physiological and pathophysiological roles of human cardiac myosin light-chain 1 (LC1s), we developed two novel monoclonal antibodies (KA1 and KB1) against human cardiac LC1s and examined LC1s in normal and pathological hearts immunohistochemically. KA1 and KB1 were specific only for atrial LC1 (ALC1) and for both ALC1 and ventricular LC1 (VLC1), respectively, in human hearts. Among human tissues tested, including skeletal muscle, vascular smooth muscle, and liver, KA1 did not crossreact with proteins in any other tissues than atria, whereas KB1 crossreacted with the slow-type LC1 of skeletal muscle. Among adult mammalian hearts of several other species including pig, dog, hamster, and rat, KA1 and KB1 crossreacted only with ALC1 and with both ALC1 and VLC1, respectively. ALC1 was strongly and uniformly observed in human fetal atria and ventricles and in normal adult human atria, but sporadically in normal adult human ventricles. In the overloaded ventricle (dilated cardiomyopathy), ALC1 was highly augmented but not uniform. These results suggest that the fetal VLC1 is immunohistochemically identical to the adult type of ALC1 and that ALC1 is expressed homogeneously in human fetal ventricles and sporadically in normal adult ventricles, and is re-expressed heterogeneously and in an increased amount in the overloaded ventricle.
30
Vassileva, Zornitsa, e Anna Kaneva. "Echocardiographic preoperative evaluation of unbalanced atrioventricular septal defect". Bulgarian Cardiology 26, n. 2 (6 luglio 2020): 46–58. http://dx.doi.org/10.3897/bgcardio.26.e52123.
Testo completoAbstract (sommario):
Unbalanced atrioventricular septal defect is seen by 10-15% of the patients with this congenital heart disease and poses serious challenges for the treating physicians regarding the choice of the most suitable operative intervention. The forms with moderate degree of unbalance between the two ventricles, especially when the size of the left ventricle is considered borderline, make the choice between two-ventricle correction and single-ventricle palliation quite difficult. The most important factor when judging the degree of unbalance is not the size of the ventricles but rather the redistribution of blood flow. The use of different echocardiographic measurements could contribute to the more precise determination of the indications for one of the two surgical strategies with resulting improvement of patient outcome.
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Naftel, Robert P., Chevis N. Shannon, Gavin T. Reed, Richard Martin, Jeffrey P. Blount, R. Shane Tubbs e John C. Wellons. "Small-ventricle neuroendoscopy for pediatric brain tumor management". Journal of Neurosurgery: Pediatrics 7, n. 1 (gennaio 2011): 104–10. http://dx.doi.org/10.3171/2010.10.peds10338.
Testo completoAbstract (sommario):
Object The use of intraventricular endoscopy to achieve diagnosis or to resect accessible intraventricular or paraventricular tumors has been described in the literature in both adults and children. Traditionally, these techniques have not been used in patients with small ventricles due to the perceived risk of greater morbidity. The authors review their experience with the effectiveness and safety of endoscopic brain tumor management in children with small ventricles. Methods Between July 2002 and December 2009, 24 children with endoscopically managed brain tumors were identified. Radiological images were reviewed by a radiologist blinded to study goals and clinical setting. Patients were categorized into small-ventricle and ventriculomegaly groups based on frontal and occipital horn ratio. Surgical success was defined a priori and analyzed between groups. Trends were identified in selected subgroups, including complications related to pathological diagnosis and surgeon experience. Results Six children had small ventricles and 18 had ventriculomegaly. The ability to accomplish surgical goals was statistically equivalent in children with small ventricles and those with ventriculomegaly (83% vs 89%, respectively, p = 1.00). There were no complications in the small-ventricle cohort, but in the ventriculomegaly cohort there were 2 cases of postoperative hemorrhages and 1 case of infection. All hemorrhagic complications occurred in patients with high-grade tumor histopathological type and were early in the surgeon's endoscopic career. Conclusions Based on our experience, endoscopy should not be withheld in children with intraventricular tumors and small ventricles. Complications appear to be more dependent on tumor histopathological type and surgeon experience than ventricular size.
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Park, Jong-Hyuk, Yong-Sook Park, Jong-Sik Suk, Seung-Won Park, Sung-Nam Hwang, Taek-Kyun Nam, Young-Baeg Kim e Won-Bok Lee. "Cerebrospinal fluid pathways from cisterns to ventricles in N-butyl cyanoacrylate–induced hydrocephalic rats". Journal of Neurosurgery: Pediatrics 8, n. 6 (dicembre 2011): 640–46. http://dx.doi.org/10.3171/2011.8.peds1190.
Testo completoAbstract (sommario):
Object Cerebrospinal fluid typically enters the subarachnoid space from the ventricles via the fourth ventricular foramina. However, there is clinical evidence that CSF also flows in the opposite direction. Ventricular reflux of CSF from a cistern is a well-known phenomenon in radioisotope studies in patients with normal-pressure hydrocephalus. Additionally, the presence of ventricular blood in acute subarachnoid hemorrhage is frequently observed. The goal of this investigation was to examine the potential CSF pathways from cisterns to ventricles. The authors examined pathways in rat models in which they occluded the fourth ventricular outlets and injected a tracer into the subarachnoid space. Methods The model for acute obstructive hydrocephalus was induced using N-butyl cyanoacrylate (NBCA) in 10 Sprague-Dawley rats. After 3 days, cationized ferritin was infused into the lumbar subarachnoid space to highlight retrograde CSF flow pathways. The animals were sacrificed at 48 hours, and the brains were prepared. The CSF flow pathway was traced by staining the ferritin with ferrocyanide. Results Ferritin was observed in the third ventricle in 7 of 8 rats with hydrocephalus and in the temporal horn of the lateral ventricles in 4 of 8 rats with hydrocephalus. There was no definite staining in the aqueduct, which suggests that the ventricular reflux originated from routes other than through the fourth ventricular outlets. Conclusions The interfaces between the quadrigeminal cistern and third ventricle and those between the ambient cistern and lateral ventricle appear to be potential sites of CSF reflux from cisterns to ventricles in obstructive hydrocephalus.
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Johnson, Tannis A., Alrich L. Gray, Jean-Marie Lauenstein, Stephen S. Newton e V. John Massari. "Parasympathetic control of the heart. I. An interventriculo-septal ganglion is the major source of the vagal intracardiac innervation of the ventricles". Journal of Applied Physiology 96, n. 6 (giugno 2004): 2265–72. http://dx.doi.org/10.1152/japplphysiol.00620.2003.
Testo completoAbstract (sommario):
The locations, projections, and functions of the intracardiac ganglia are incompletely understood. Immunocytochemical labeling with the general neuronal marker protein gene product 9.5 (PGP 9.5) was used to determine the distribution of intracardiac neurons throughout the cat atria and ventricles. Fluorescence microscopy was used to determine the number of neurons within these ganglia. There are eight regions of the cat heart that contain intracardiac ganglia. The numbers of neurons found within these intracardiac ganglia vary dramatically. The total number of neurons found in the heart (6,274 ± 1,061) is almost evenly divided between the atria and the ventricles. The largest ganglion is found in the interventricular septum (IVS). Retrogradely labeled fluorescent tracer studies indicated that the vagal intracardiac innervation of the anterior surface of the right ventricle originates predominantly in the IVS ganglion. A cranioventricular (CV) ganglion was retrogradely labeled from the anterior surface of the left ventricle but not from the anterior surface of the right ventricle. These new neuroanatomic data support the prior physiological hypothesis that the CV ganglion in the cat exerts a negative inotropic effect on the left ventricle. A total of three separate intracardiac ganglia innervate the left ventricle, i.e., the CV, IVS, and a second left ventricular (LV2) ganglion. However, the IVS ganglion provides the major source of innervation to both the left and right ventricles. This dual innervation pattern may help to coordinate or segregate vagal effects on left and right ventricular performance.
34
Brück, Wolfgang, Ulrich Sander, Peter Blanckenberg e Reinhard L. Friede. "Symptomatic xanthogranuloma of choroid plexus with unilateral hydrocephalus". Journal of Neurosurgery 75, n. 2 (agosto 1991): 324–27. http://dx.doi.org/10.3171/jns.1991.75.2.0324.
Testo completoAbstract (sommario):
✓ Xanthogranulomas involving the choroid plexus of the lateral ventricles are generally asymptomatic lesions. The case is reported of a 50-year-old man in whom a xanthogranuloma of the choroid plexus had occluded the left trigone, causing unilateral hydrocephalus of the left temporal horn and neurological symptoms. A review of the literature shows that xanthogranulomas of the glomus of the lateral ventricles differ from the xanthomatous cystic lesions of the third ventricle, which are probably akin to colloid cysts.
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Ding, Weihao, Sandeep Bhushan, Chen Ma, Yifan Yan e Zongwei Xiao. "Right Ventricle Involvement in Hypertrophic Cardiomyopathy and Role of Cardiac Magnetic Resonance in Hypertrophic Cardiomyopathy: Review Article". Heart Surgery Forum 24, n. 4 (25 agosto 2021): E746—E750. http://dx.doi.org/10.1532/hsf.3977.
Testo completoAbstract (sommario):
Hypertrophic cardiomyopathy (HCM) is the most common genetic cardiac disease, and its main characteristic is symmetrical or asymmetrical hypertrophy of the left ventricle and/or right ventricle. Most previous studies mainly include the left ventricle for definition of HCM, thus neglecting the right ventricle. But recently, many studies have reported the right ventricular involvement in HCM. Histopathological results showed that similar pathogenic changes in both the right and left ventricles, which suggests common myopathic processes and sarcomere genetic mutations. Cardiovascular magnetic resonance (CMR) is a gold standard imaging modality to assess heart anatomy and function and provides highly accurate and reproducible measurements. CMR is very useful in characterizing the various phenotypes of right and left ventricles in HCM. CMR also can be useful in detecting early and dominant phenotypic expression of HCM. Due to the complex geometry of the right ventricle and its retrosternal position, echocardiography may not provide accurate measurements. CMR also provides more accurate and repeatable right ventricular measurements. Thus, right ventricle evaluation along with left ventricle should routinely be done for better assessment of HCM patients.
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Blagonravov, M. L., M. V. Onufriev, E. A. Demurov, N. V. Guliaeva e V. A. Frolov. "Assessment of caspase-3 activity in rabbit myocardial tissue during experimental hemodynamic overload of the left ventricle of the heart". Biomeditsinskaya Khimiya 56, n. 6 (2010): 719–25. http://dx.doi.org/10.18097/pbmc20105606719.
Testo completoAbstract (sommario):
It's well known that chronic overload of the cardiac left ventricle is accompanied by an increase in the cardiomyocyte apoptosis rate. However direction and extent of programmed cell death changes under an acute overload of the left ventricle still requires detailed investigation. Caspase-3 activity has been investigated in myocardium of rabbits on the 1, 3 and 5 days after modeling of left ventricle hemodynamic overload caused by surgical narrrowing of the ascending aorta. Control group included intact animals. It was found that caspase-3 activity significantly increased in both ventricles on day 1; it increased more than twofold above controls on day 3; it began to decrease by day 5. On the basis of the obtained data it was concluded that: an acute hemodynamic overload of the left ventricle is a cause of apoptosis acceleration in the myocardial tissue of both cardiac ventricles during first days of the investigated process.
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Bakici, C., RO Akgun, D. Ozen, O. Alagin e C. Oto. "The volume fraction values of the brain compartments using the Cavalieri principle and a 3T MRI in brachycephalic and mesocephalic dogs". Veterinární Medicína 64, No. 11 (20 novembre 2019): 482–89. http://dx.doi.org/10.17221/33/2019-vetmed.
Testo completoAbstract (sommario):
This study was aimed at: 1) estimating the volume and the volume fraction values of brain ventricles, grey matter and white matter with the Cavalieri principle and 2) creating three-dimensional reconstruction models of the brain ventricles by using magnetic resonance imaging. The brain structures of dogs were scanned with a 3T magnetic resonance system. The volumes of the total brain, the grey matter, the white matter, the lateral ventricle, the third ventricle, the cerebral aqueduct and the fourth ventricle of both sides were estimated separately by using a combination of the Cavalieri principle and the point-counting method. In addition to that, magnetic resonance images of dog brains were uploaded to the 3D slicer software to design the three-dimensional reconstruction models. The mean volume fraction values of the left and right lateral ventricle, third ventricle, cerebral aqueduct, and fourth ventricle were 1.83 ± 0.14%, 1.75 ± 0.1%, 0.7 ± 0.07%, 0.2 ± 0.04%, and 1 ± 0.32% for the brachycephalic dogs and 1.69 ± 0.04%, 1.66 ± 0.03%, 0.91 ± 0.03%, 0.27 ± 0.05%, and 0.71 ± 0.15% for the mesocephalic dogs, respectively. There was no statistically significant difference between the brachycephalic and mesocephalic dogs in all the volume fraction values (P > 0.05). This study showed the volume and the volume fraction values of the brain ventricles and the structures in the different types of the dogs’ head shapes. These volume fraction values can be essential data for determining some diseases. Magnetic resonance imaging can be used for precise volume estimations in combination with the Cavalieri principle and the point-counting method.
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Radik, M., G. Doka, E. Malikova, P. Krenek e J. Klimas. "Voluntary exercise and testosterone therapy caused increase in percentage of Myh6 and expression of oxidative stress marker Cybb in left ventricles of rats". European Pharmaceutical Journal 63, n. 1 (1 settembre 2016): 12–15. http://dx.doi.org/10.1515/afpuc-2016-0007.
Testo completoAbstract (sommario):
Abstract Aim: The aim of this study is to identify a possible damage to heart ventricles caused by supraphysiological doses of testosterone, voluntary physical activity or their combination. Methods: In the 8-week long experiment, 10-12 weeks old male Wistar rats were administered testosterone depot in dose of 100 mg/kg (TES, n = 15) or vehiculum (CON, n = 12) once a week subcutaneously. Next groups injected with testosterone (SPOTES, n = 12) or vehiculum (SPO, n = 12) were running in exercise wheels ad libitum. Gene expressions in left and right ventricles of the heart were measured by quantitative reverse transcription polymerase chain reaction method. Results:ln left ventricles of the testosterone groups, we observed a mild but significant increase in the percentage of Myh6 myosin heavy chain isoform and higher expression of NADPH oxidase subunit Cybb (*p < 0.05). Conclusions:Testosterone affected the expression of genes related to contractile apparatus and oxidative stress in the left ventricle but not in right ventricle of the heart of rats. The observed level of physical activity did not have a compelling effect on the expression of measured genes.
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Wehrwein, Erica A., Lindsay M. Parker, Anna A. Wright, John M. Spitsbergen, Martin Novotny, Dagmar Babankova, Greg M. Swain, Beth A. Habecker e David L. Kreulen. "Cardiac norepinephrine transporter protein expression is inversely correlated to chamber norepinephrine content". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 295, n. 3 (settembre 2008): R857—R863. http://dx.doi.org/10.1152/ajpregu.00190.2008.
Testo completoAbstract (sommario):
The cardiac neuronal norepinephrine (NE) transporter (NET) in sympathetic neurons is responsible for uptake of released NE from the neuroeffector junction. The purpose of this study was to assess the chamber distribution of cardiac NET protein measured using [3H]nisoxetine binding in rat heart membranes and to correlate NE content to NET amount. In whole mounts of atria, NET was colocalized in nerve fibers with tyrosine hydroxylase (TH) immunoreactivity. NE content expressed as micrograms NE per gram tissue was lowest in the ventricles; however, NET binding was significantly higher in the left ventricle than the right ventricle and atria ( P < 0.05), resulting in a significant negative correlation ( r2 = 0.922; P < 0.05) of NET to NE content. The neurotoxin 6-hydroxydopamine, an NET substrate, reduced NE content more in the ventricles than the atria, demonstrating functional significance of high ventricular NET binding. In summary, there is a ventricular predominance of NET binding that corresponds to a high NE reuptake capacity in the ventricles, yet negatively correlates to tissue NE content.
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Anderson, Robert H., e Diane Spicer. "Fistulous communications with the coronary arteries in the setting of hypoplastic ventricles". Cardiology in the Young 20, S3 (dicembre 2010): 86–91. http://dx.doi.org/10.1017/s1047951110001125.
Testo completoAbstract (sommario):
AbstractNeonates born with hypoplastic left heart syndrome now have a remarkably improved prognosis compared with the situation existing before the development of the Norwood sequence of operative procedures. Some of those born with hypoplastic right ventricles in the setting of pulmonary atresia with an intact ventricular septum, however, still have a relatively poor prognosis. In part this reflects the presence of fistulous communication between the cavity of the right hypoplastic right ventricle and the coronary arterial tree. Such fistulous communications are now increasingly recognised as being important in the setting of hypoplastic left heart syndrome. In this brief review, we describe the anatomy of the communications. Those found with hypoplastic right ventricles are seen most frequently when the cavity of the ventricle effectively represents only the inlet, this in turn reflecting mural overgrowth of the apical trabecular and outlet components during foetal development. This almost certainly reflects an earlier appearance of the pulmonary valvar lesion that promotes the cavitary hypoplasia. In those with hypoplastic left ventricles, the key feature differentiating those with fistulous communications is the presence of a patent mitral valve, since the left ventricle is typically no more than a virtual slit in postero-inferior ventricular wall in the setting of mitral valvar atresia or absence of the left atrioventricular connection.
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Lopez, Leo, Meryl S. Cohen, Robert H. Anderson, Andrew N. Redington, David G. Nykanen, Daniel J. Penny, John E. Deanfield e Benjamin W. Eidem. "Unnatural history of the right ventricle in patients with congenitally malformed hearts". Cardiology in the Young 20, S3 (dicembre 2010): 107–12. http://dx.doi.org/10.1017/s1047951110001150.
Testo completoAbstract (sommario):
AbstractThe long-term outcome of patients with congenitally malformed hearts involving abnormal right ventricular morphology and haemodynamics is variable. In most instances, the patients are at risk for right ventricular failure, in part due to morphological differences between the right and left ventricles and their response to chronic volume and pressure overload. In patients after repair of tetralogy of Fallot, and after balloon valvotomy for valvar pulmonary stenosis, pulmonary regurgitation is the most significant risk factor for right ventricular dysfunction. In patients with a dominant right ventricle after Fontan palliation, and in those with systemic right ventricles in association with surgically or congenitally corrected transposition, the right ventricle is not morphologically capable of dealing with chronic exposure to the high afterload of the systemic circulation. In patients with Ebstein’s malformation of the tricuspid valve, the degree of atrialisation of the right ventricle determines how well the right ventricle will function as the pump for the pulmonary vascular bed.
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Nouette-Gaulain, Karine, François Forestier, Monique Malgat, Roger Marthan, Jean-Pierre Mazat e François Sztark. "Effects of Bupivacaine on Mitochondrial Energy Metabolism in Heart of Rats following Exposure to Chronic Hypoxia". Anesthesiology 97, n. 6 (1 dicembre 2002): 1507–11. http://dx.doi.org/10.1097/00000542-200212000-00024.
Testo completoAbstract (sommario):
Background Adaptation to chronic exposure to hypoxia alters energy metabolism in the heart, particularly in the left ventricle, which undergoes a loss in oxidative capacity. Highly lipophilic local anesthetics interfere with mitochondrial energy metabolism. The purpose of this study was to compare the effects of bupivacaine on mitochondrial energy metabolism in heart of rats subjected to normoxic or hypoxic environments. Methods Male Wistar rats (n = 10) were subjected to hypobaric hypoxia (simulated altitude = 5,000 m, 380 mmHg) for 2 weeks. Control rats (n = 10) were maintained in an ambient normoxic environment. Mitochondrial metabolism (oxygen consumption and adenosine triphosphate synthesis) was assessed using saponin-skinned ventricular fibers. Bupivacaine (0-5 mM) was tested on both left and right ventricles of normoxic or hypoxic heart. Results In animals exposed to hypobaric hypoxia for 14 days, cardiac mass significantly increased, and the right-to-left ventricular ratio was approximately twofold (0.48 +/- 0.11 vs. 0.22 +/- 0.04, P < 0.05). Oxygen consumption and adenosine triphosphate synthesis were significantly lower in the hypoxic left ventricles but not in the right ones. The uncoupling effect of bupivacaine was more pronounced in the left ventricle from hypoxic heart than in the right ventricle; the bupivacaine-induced decrease in the adenosine triphosphate synthesis rate and in the adenosine triphosphate-to-oxygen ratio was significantly greater in the hypoxic left ventricle than in the normoxic one. Conclusions Chronic hypoxia impairs cardiac energy metabolism in left ventricles and enhances the depressant effects of bupivacaine on mitochondrial functions.
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Ozkutlu, Suheyla, e Dursun Alehan. "Parallel arterial trunks with discordant atrioventricular and concordant ventriculo-arterial connections in mirror-imaged arrangement". Cardiology in the Young 17, n. 5 (ottobre 2007): 560–62. http://dx.doi.org/10.1017/s1047951107000947.
Testo completoAbstract (sommario):
AbstractCardiac malformations are very rare in which the great arteries arise from their appropriate ventricles, but are abnormally related to each other. Here, we present a patient with mirror-imaged atrial arrangement and a left-sided heart who has parallel arterial trunks with discordant atrioventricular and concordant ventriculo-arterial connections. The ventricles were related in supero-inferior fashion, the left ventricle being anterior and superior, this being an additional feature which, to the best of our knowledge, has not previously been described in this setting.
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Nouette-Gaulain, Karine, Matthieu Biais, Jean-Pierre Savineau, Roger Marthan, Jean-Pierre Mazat, Thierry Letellier e François Sztark. "Chronic hypoxia-induced alterations in mitochondrial energy metabolism are not reversible in rat heart ventricles". Canadian Journal of Physiology and Pharmacology 89, n. 1 (gennaio 2011): 58–66. http://dx.doi.org/10.1139/y10-105.
Testo completoAbstract (sommario):
Chronic hypoxia alters mitochondrial energy metabolism. In the heart, oxidative capacity of both ventricles is decreased after 3 weeks of chronic hypoxia. The aim of this study was to evaluate the reversal of these metabolic changes upon normoxia recovery. Rats were exposed to a hypobaric environment for 3 weeks and then subjected to a normoxic environment for 3 weeks (normoxia-recovery group) and compared with rats maintained in a normoxic environment (control group). Mitochondrial energy metabolism was differentially examined in both left and right ventricles. Oxidative capacity (oxygen consumption and ATP synthesis) was measured in saponin-skinned fibers. Activities of mitochondrial respiratory chain complexes and antioxidant enzymes were measured on ventricle homogenates. Morphometric analysis of mitochondria was performed on electron micrographs. In normoxia-recovery rats, oxidative capacities of right ventricles were decreased in the presence of glutamate or palmitoyl carnitine as substrates. In contrast, oxidation of palmitoyl carnitine was maintained in the left ventricle. Enzyme activities of complexes III and IV were significantly decreased in both ventricles. These functional alterations were associated with a decrease in numerical density and an increase in size of mitochondria. Finally, in the normoxia-recovery group, the antioxidant enzyme activities (catalase and glutathione peroxidase) increased. In conclusion, alterations of mitochondrial energy metabolism induced by chronic hypoxia are not totally reversible. Reactive oxygen species could be involved and should be investigated under such conditions, since they may represent a therapeutic target.
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Markel, Troy A., Paul R. Crisostomo, Meijing Wang, Jeremy L. Herrmann, Aaron M. Abarbanell e Daniel R. Meldrum. "Right ventricular TNF resistance during endotoxemia: the differential effects on ventricular function". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 293, n. 5 (novembre 2007): R1893—R1897. http://dx.doi.org/10.1152/ajpregu.00359.2007.
Testo completoAbstract (sommario):
Right and left ventricular myocytes originate from different cellular progenitors; however, it is unknown whether these cells differ in their response to endotoxemia. We hypothesized that 1) the percentage of endotoxemic functional depression within the right ventricle (RV) would be smaller than that of the left ventricle; and 2) that better RV function would correlate with lower levels of right ventricular TNF production. Adult Sprague-Dawley rats were divided into right and left control and endotoxin groups. Controls received vehicle, while endotoxin groups received LPS at 20 mg/kg ip. Hearts were excised either 2 or 6 h after injection. Hearts excised at 2 h were assayed for TNF, IL-6, TNF receptor 1 (TNFR1), TNFR2, and via ELISA, while hearts excised at 6 h were assayed via the Langendorff model. The percentage of cardiac functional depression, exhibited as developed pressure, contractility, and rate of relaxation (expressed as a percentage of control) was significantly smaller in right ventricles compared with left ventricles following endotoxin exposure. Tissue levels of TNF were significantly elevated in both right and left ventricles 2 h after endotoxin exposure, and right ventricular endotoxin groups expressed higher levels of TNF compared with their left ventricular counterparts. No significant differences in IL-6, TNFR1, or TNFR2 levels were noted between endotoxin-exposed ventricles. This is the first study to demonstrate that right and left ventricular function differs after endotoxin exposure.
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Gu, J. A., e L. Gonzalez-Lavin. "Light and electron microscopic localization of atrial natriuretic peptide in the heart of spontaneously hypertensive rat." Journal of Histochemistry & Cytochemistry 36, n. 10 (ottobre 1988): 1239–49. http://dx.doi.org/10.1177/36.10.2971091.
Testo completoAbstract (sommario):
Atrial natriuretic peptide (ANP) is a newly discovered peptide hormone present mainly in the atria. We investigated the occurrence and distribution of ANP immunoreactivity in the myocardiocytes of the ventricles of spontaneously hypertensive rats by use of immunocytochemistry at both light and electron microscopic level. ANP immunoreactivity was found in the specific granules in the cytoplasm of the cardiocytes in the subendocardium and the myocardium of the ventricles, as well as in the atria. The specific granules found in the ventricles of hypertensive rats were similar in size, shape, and ANP immunoreactive content to those in the atria. The abundance of ANP immunoreactivity in the left ventricle is greater than that in the right, and appears to increase with increasing severity of hypertension. Conversely, the overall content of ANP in the atria of hypertensive rats was decreased when compared with that in age-matched normotensive rats. The present findings indicate that ventricles may become a major source for ANP synthesis and release during hypertension, and may play important roles in cardiac endocrine pathology and cardiac hypertrophy.
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Roth, Jonathan, Marian M. Bercu e Shlomi Constantini. "Combined open microsurgical and endoscopic resection of hypothalamic hamartomas". Journal of Neurosurgery: Pediatrics 11, n. 5 (maggio 2013): 491–94. http://dx.doi.org/10.3171/2013.2.peds12275.
Testo completoAbstract (sommario):
Hypothalamic hamartomas (HHs) are typically located within the vicinity of the third ventricle. They can be attached to the walls of the third ventricle, within the interpeduncular cistern (third ventricle floor), and/or attached to the mammillary bodies and hypothalamus. Depending on their location, resection is performed either through the third ventricle, approaching from above, or via a frontotemporal craniotomy (pterional or frontoorbital), approaching from below. “Above” approaches typically include the transcallosal–anterior interforniceal approach, and recently, purely endoscopic approaches performed transforaminally. The authors present a combined open and endoscopic approach for resection of HHs located within the third ventricle. They used this approach in 2 young girls with relatively small lateral and third ventricles. Following an interhemispheric, transcallosal approach and exposure of the right foramen of Monro, an endoscope was inserted through the foramen, which enabled safe resection of the HH. The main advantage of the combined approach is when the lateral and third ventricles are relatively small, making a purely endoscopic approach more challenging and possibly riskier.
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Orozco, Gustavo A., Joshua H. Smith e José J. García. "Three-dimensional nonlinear finite element model to estimate backflow during flow-controlled infusions into the brain". Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 234, n. 9 (9 luglio 2020): 1018–28. http://dx.doi.org/10.1177/0954411920937220.
Testo completoAbstract (sommario):
Convection-enhanced delivery is a technique to bypass the blood–brain barrier and deliver therapeutic drugs into the brain tissue. However, animal investigations and preliminary clinical trials have reported reduced efficacy to transport the infused drug in specific zones, attributed mainly to backflow, in which an annular gap is formed outside the catheter and the fluid preferentially flows toward the surface of the brain rather than through the tissue in front of the cannula tip. In this study, a three-dimensional human brain finite element model of backflow was developed to study the influence of anatomical structures during flow-controlled infusions. Predictions of backflow length were compared under the influence of ventricular pressure and the distance between the cannula and the ventricles. Simulations with zero relative ventricle pressure displayed similar backflow length predictions for larger cannula-ventricle distances. In addition, infusions near the ventricles revealed smaller backflow length and the liquid was observed to escape to the longitudinal fissure and ventricular cavities. Simulations with larger cannula-ventricle distances and nonzero relative ventricular pressure showed an increase of fluid flow through the tissue and away from the ventricles. These results reveal the importance of considering both the subject-specific anatomical details and the nonlinear effects in models focused on analyzing current and potential treatment options associated with convection-enhanced delivery optimization for future clinical trials.
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Sedova, Ksenia A., Sergey L. Goshka, Vladimir A. Vityazev, Dmitriy N. Shmakov e Jan E. Azarov. "Load-induced changes in ventricular repolarization: evidence of autonomic modulation". Canadian Journal of Physiology and Pharmacology 89, n. 12 (dicembre 2011): 935–44. http://dx.doi.org/10.1139/y11-098.
Testo completoAbstract (sommario):
Augmented hemodynamic load increases the risk of arrhythmogenesis by modulating cardiac repolarization duration. We hypothesized that the intervention on the autonomic tone may affect the load-dependent changes in ventricular repolarization. Activation–recovery intervals were measured in unipolar electrograms simultaneously recorded from 64 ventricular epicardial leads, in a total of 26 chinchilla rabbits in resting conditions, and after 1 and 10 min of aortic stenosis. Eleven animals were given atropine and propranolol before the loading. The short-term stenosis decreased the activation–recovery intervals in the right ventricle, whereas the prolonged overload increased the repolarization duration in both ventricles. The treatment with the β-adrenergic and M-cholinergic blockers prolonged the activation–recovery intervals, especially at the left ventricle, attenuating the apicobasal and interventricular gradients of repolarization duration seen in the baseline state. Further ventricular loading shortened the repolarization duration in both ventricles in animals with autonomic blockade. Thus, the autonomic tone was shown to be essential for the development of repolarization heterogeneity across the ventricles. The autonomic blockade transformed the biphasic changes of activation–recovery intervals into their monophasic shortening at aortic stenosis.
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Aoki, Nobuhiko, e Hiroshi Mizutani. "Communicating Triventricular Hydrocephalus and Its Treatment with a Lumboperitoneal Shunt". Neurosurgery 16, n. 4 (1 aprile 1985): 557–61. http://dx.doi.org/10.1097/00006123-198504000-00020.
Testo completoAbstract (sommario):
Abstract With computed tomography, triventricular hydrocephalus shows enlargement of the 3rd and both lateral ventricles with a nearly normal size 4th ventricle. Triventricular hydrocephalus has been described as noncommunicating because of aqueductal stenosis or obstruction. The authors, however, have encountered three patients whose computed tomographic (CT) images were those of triventricular hydrocephalus despite a patent aqueduct. This condition may be suitably referred to as communicating triventricular hydrocephalus because in all cases metrizamide CT cisternography demonstrated the communication between the spinal subarachnoid space and both lateral ventricles. The authors discuss its treatment with a lumboperitoneal shunt.