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1
Reid, Anthony. "The Olympic Cu-Au Province, Gawler Craton: A Review of the Lithospheric Architecture, Geodynamic Setting, Alteration Systems, Cover Successions and Prospectivity." Minerals 9, no. 6 (June 20, 2019): 371. http://dx.doi.org/10.3390/min9060371.
Повний текст джерелаАнотація:
The Olympic Cu-Au Province is a metallogenic province in South Australia that contains one of the world’s most significant Cu-Au-U resources in the Olympic Dam deposit. The Olympic Cu-Au Province also hosts a range of other iron oxide-copper-gold (IOCG) deposits including Prominent Hill and Carrapateena. This paper reviews the geology of the Olympic Cu-Au Province by investigating the lithospheric architecture, geodynamic setting and alteration systematics. In addition, since the province is almost entirely buried by post-mineral cover, the sedimentary cover sequences are also reviewed. The Olympic Cu-Au Province formed during the early Mesoproterozoic, ca. 1.6 Ga and is co-located with a fundamental lithospheric boundary in the eastern Gawler Craton. This metallogenic event was driven in part by melting of a fertile, metasomatized sub-continental lithospheric mantle during a major regional tectonothermal event. Fluid evolution and multiple fluid mixing resulted in alteration assemblages that range from albite, magnetite and other higher temperature minerals to lower temperature assemblages such as hematite, sericite and chlorite. IOCG mineralisation is associated with both high and low temperature assemblages, however, hematite-rich IOCGs are the most economically significant. Burial by Mesoproterzoic and Neoproterozoic-Cambrian sedimentary successions preserved the Olympic Cu-Au Province from erosion, while also providing a challenge for mineral exploration in the region. Mineral potential modelling identifies regions within the Olympic Cu-Au Province and adjacent Curnamona Province that have high prospects for future IOCG discoveries. Exploration success will rely on improvements in existing potential field and geochemical data, and be bolstered by new 3D magnetotelluric surveys. However, drilling remains the final method for discovery of new mineral resources.
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Najafi, Ali, Mohammad Hassan Karimpour, and Majid Ghaderi. "Application of fuzzy AHP method to IOCG prospectivity mapping: A case study in Taherabad prospecting area, eastern Iran." International Journal of Applied Earth Observation and Geoinformation 33 (December 2014): 142–54. http://dx.doi.org/10.1016/j.jag.2014.05.003.
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Campos, Daniela Schievano de, Adalene Moreira Silva, Catarina Laboure Bemfica Toledo, Marcelo Juliano de Carvalho, Vinícius Gomes Rodrigues, and Kawinã Araujo. "Prospectivity analysis of gold and iron oxide copper-gold-(silver) mineralizations from the Faina Greenstone Belt, Brazil, using multiple data sets." Brazilian Journal of Geology 47, no. 4 (December 2017): 561–90. http://dx.doi.org/10.1590/2317-4889201720170012.
Повний текст джерелаАнотація:
ABSTRACT: The Faina Greenstone Belt is located in the southern sector of the Goiás Archean Block and has been investigated since the 18th century because of its gold deposits. Recent studies have revealed the polymetallic potential of the belt, which is indicated by anomalous levels of Ag, Cu, Fe and Co in addition to Mn, Ba, Li, Ni, Cr and Zn. This study was developed based on a detailed analysis of two selected target sites, Cascavel and Tinteiro, and multiple data sets, such as airborne geophysics, geochemistry and geological information. These datasets were used to create a final prospectivity map using the fuzzy logic technique. The gold mineralization of Cascavel target is inserted in an orogenic system and occurs in two overlapping quartz veins systems, called Mestre-Cascavel and Cuca, embedded in quartzite with an average thickness 50 cm and guidance N45º-60ºW/25ºSW with free coarse gold in grains 2-3 mm to 3 cm. The prospectivity map created for this prospect generated four first-order favorable areas for mineralization and new medium-favorability foci. The Tinteiro area, derived from studies conducted by Orinoco do Brasil Mineração Ltda., shows polymetallic mineralization associated with an iron oxide-copper-gold ore deposit (IOCG) system posterior to Cascavel target mineralization. Its prospectivity map generated 19 new target sites with the potential for Au, Cu and Ag mineralization, suggesting new directions for future prospecting programs.
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Gloyn-Jones, Jonathan Nicholas, Ian James Basson, Ben Stoch, Corné Koegelenberg, and Michael-John McCall. "Integration of Stress–Strain Maps in Mineral Systems Targeting for IOCG Mineralisation within the Mt. Woods Inlier, Gawler Craton, South Australia." Minerals 12, no. 6 (May 31, 2022): 699. http://dx.doi.org/10.3390/min12060699.
Повний текст джерелаАнотація:
The application of finite element analysis is used to simulate the relative distribution and magnitude of stress–strain conditions during a geologically brief, NNW-SSE-oriented, extensional event (1595 Ma to 1590 Ma), co-incident with IOCG-hydrothermal fluid flow and mineralisation across the Mt Woods Inlier, Gawler Craton, South Australia. Differential stress and shear strain maps across the modelled terrane highlight regions that were predisposed to strain localization, extensional failure and fluid throughput during the simulated mineralisation event. These maps are integrated with other datasets and interpretation layers, one of which is a proposed structural–geometrical relationship apparent in many world-class IOCG deposits, including Prominent Hill, Olympic Dam, Sossego, Salobo, Cristalino and Candelaria. These deposits occur at steeply plunging, pipe-like intersections of conjugate extensional systems of faults, shears and/or contacts, wherein the obtuse angle may have been bisected by the maximum principal extensional axis (viz., σ3) during mineralisation. Several other layers are also used for the generation of targets, such as distance from major shear zones, favourable host lithologies, and proximity to tectonostratigraphic contacts of markedly contrasting competency. The result is an integrated target index or heat map for IOCG prospectively across the Mt. Woods Inlier.
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Bianco, Kristina, Robert Norton, Frank Schwab, Justin S. Smith, Eric Klineberg, Ibrahim Obeid, Gregory Mundis, et al. "Complications and intercenter variability of three-column osteotomies for spinal deformity surgery: a retrospective review of 423 patients." Neurosurgical Focus 36, no. 5 (May 2014): E18. http://dx.doi.org/10.3171/2014.2.focus1422.
Повний текст джерелаАнотація:
Object Three-column resection osteotomies (3COs) are commonly performed for sagittal deformity but have high rates of reported complications. Authors of this study aimed to examine the incidence of and intercenter variability in major intraoperative complications (IOCs), major postoperative complications (POCs) up to 6 weeks postsurgery, and overall complications (that is, both IOCs and POCs). They also aimed to investigate the incidence of and intercenter variability in blood loss during 3CO procedures. Methods The incidence of IOCs, POCs, and overall complications associated with 3COs were retrospectively determined for the study population and for each of 8 participating surgical centers. The incidence of major blood loss (MBL) over 4 L and the percentage of total blood volume lost were also determined for the study population and each surgical center. Complication rates and blood loss were compared between patients with one and those with two osteotomies, as well as between patients with one thoracic osteotomy (ThO) and those with one lumbar or sacral osteotomy (LSO). Risk factors for developing complications were determined. Results Retrospective review of prospectively acquired data for 423 consecutive patients who had undergone 3CO at 8 surgical centers was performed. The incidence of major IOCs, POCs, and overall complications was 7%, 39%, and 42%, respectively, for the study population overall. The most common IOC was spinal cord deficit (2.6%) and the most common POC was unplanned return to the operating room (19.4%). Patients with two osteotomies had more POCs (56% vs 38%, p = 0.04) than the patients with one osteotomy. Those with ThO had more IOCs (16% vs 6%, p = 0.03), POCs (58% vs 34%, p < 0.01), and overall complications (67% vs 37%, p < 0.01) than the patients with LSO. There was significant variation in the incidence of IOCs, POCs, and overall complications among the 8 sites (p < 0.01). The incidence of MBL was 24% for the study population, which varied significantly between sites (p < 0.01). Patients with MBL had a higher risk of IOCs, POCs, and overall complications (OR 2.15, 1.76, and 2.01, respectively). The average percentage of total blood volume lost was 55% for the study population, which also varied among sites (p < 0.01). Conclusions Given the complexity of 3COs for spinal deformity, it is important for spine surgeons to understand the risk factors and complication rates associated with these procedures. In this study, the overall incidence of major complications following 3CO procedures was 42%. Risks for developing complications included an older age (> 60 years), two osteotomies, ThO, and MBL.
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Abdolmaleki, M., T. M. Rasmussen, and M. K. Pal. "EXPLORATION OF IOCG MINERALIZATIONS USING INTEGRATION OF SPACE-BORNE REMOTE SENSING DATA WITH AIRBORNE GEOPHYSICAL DATA." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B3-2020 (August 21, 2020): 9–16. http://dx.doi.org/10.5194/isprs-archives-xliii-b3-2020-9-2020.
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Abstract. Nowadays, remote sensing technologies are playing a significant role in mineral potential mapping. To optimize the exploration approach along with a cost-effective way, narrow down the target areas for a more detailed study for mineral exploration using suitable data selection and accurate data processing approaches are crucial. To establish optimum procedures by integrating space-borne remote sensing data with other earth sciences data (e.g., airborne magnetic and electromagnetic) for exploration of Iron Oxide Copper Gold (IOCG) mineralization is the objective of this study. Further, the project focus is to test the effectiveness of Copernicus Sentinel-2 data in mineral potential mapping from the high Arctic region. Thus, Inglefield Land from northwest Greenland has been chosen as a study area to evaluate the developed approach. The altered minerals, including irons and clays, were mapped utilizing Sentinel-2 data through band ratio and principal component analysis (PCA) methods. Lineaments of the study area were extracted from Sentinel-2 data using directional filters. Self-Organizing Maps (SOM) and Support Vector Machines (SVM) were used for classification and analysing the available data. Further, various thematic maps (e.g., geological, geophysical, geochemical) were prepared from the study area. Finally, a mineral prospectively map was generated by integrating the above mentioned information using the Fuzzy Analytic Hierarchy Process (FAHP). The prepared potential map for IOCG mineralization using the above approach of Inglefield Land shows a good agreement with the previous geological field studies.
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Lau, W. Y., and Arthur K. C. Li. "Is there a Role for Preoperative Infusion or Intraoperative Cholangiography?" HPB Surgery 10, no. 5 (January 1, 1997): 342–45. http://dx.doi.org/10.1155/1997/30872.
Повний текст джерелаАнотація:
Background: There has been a resurgence of interest in recent years in preoperative infusion cholangiography (PIC). The role of routine PIC compared to routine intraoperative cholangiography (IOC) has not been clearly defined.Study design: In our department between 1985 and 1991, 1,042 of 1,576 consecutive patients with biliary calculous disease had elective cholecystectomy: 694 patients were prospectively scheduled for PIC, and 348 patients were randomly allocated to IOC. The patients in the PIC and IOC groups were similar with regard to age, history of biliopancreatic complications, and laboratory findings. The cost of PIC in Sweden is nearly five times greater than the cost of IOC.Results: Satisfactory opacification of the biliary system was obtained in 90.1 and 96.8 percent of patients who underwent PIC and IOC, respectively. Preoperative infusion cholangiography required support by IOC in 19.5 percent of patients. There were no statistically significant differences between the PIC and IOC groups with regard to the incidence (7 percent in both groups) of or positive predictive value (68 and 80 percent, respectively) for bile duct stones, rate of retained stones (6 and 20 percent, respectively), intraoperative (5.6 and 6.3 percent, respectively) or postoperative (13.3 and 15.9 percent, respectively) morbidity, or incidence of bile duct anomalies (0.9 and 0.3 percent, respectively). Median operative time was longer in .patients with (95 minutes) compared to those without (75 minutes) IOC (p<0.001). More postoperative complications occurred after bile duct exploration (26 of 75 patients) compared to cholecystectomy alone (114 of 917 patients, p<0.001). The 30-day mortality was zero. Minor bile duct injuries occurred in two patients (0.2 percent) at cholecystectomy, (one with and one without bile duct exploration). In no patient was the cholangiographic finding of a biliary anomaly crucial for the safe execution of cholecystectomy.Conclusions: In our study, PIC and IOC were comparable, but routine use of either method did not promote the safety of cholecystectomy and thus their routine use is not warranted. The shorter operative time and preoperative identification of common bile duct (CBD) stones provided by PIC might favor this examination when applied selectively in patients with increased risk of having CBD stones. However, this potential advantage is offset by the need for PIC to be supported by IOC in approximately 20 percent of patients. Also, the cost of PIC is greater than the cost of IOC.
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Titiyal, Jeewan S., Manpreet Kaur, Suman Sahu, Namrata Sharma, and Rajesh Sinha. "Real-Time Assessment of Intraoperative Vaulting in Implantable Collamer Lens and Correlation with Postoperative Vaulting." European Journal of Ophthalmology 27, no. 1 (December 7, 2016): 21–25. http://dx.doi.org/10.5301/ejo.5000818.
Повний текст джерелаАнотація:
Purpose To assess the intraoperative vaulting in patients undergoing implantable collamer lens (ICL) implantation with microscope-integrated intraoperative optical coherence tomography (iOCT) and correlate it with the postoperative vaulting. Methods Forty eyes of 22 consecutive patients undergoing ICL implantation were prospectively evaluated. Vaulting was measured intraoperatively using microscope-integrated iOCT. The ICL-lenticular relationship was dynamically assessed throughout the surgery. Postoperative vaulting was measured using anterior segment optical coherence tomography on the first postoperative day and after 1 month and compared with the intraoperative vaulting. Uncorrected and best-corrected Snellen visual acuity, intraocular pressure (IOP), and anterior and posterior segments were assessed in all cases. Results The mean central vaulting noted intraoperatively was 558.4 ± 122.8 µm. Postoperative mean vaulting was 576.0 ± 131.2 µm on day 1 and 551.1 ± 122.5 µm on day 30. There was a significant correlation between the intraoperative and the postoperative day 1 vaulting (paired samples correlation: 0.969, p<0.001) and day 30 vaulting (paired samples correlation: 0.945, p<0.001). An ICL-lenticular touch was not noted at any time during the surgery. The postoperative course was uneventful and no patient developed raised IOP or lenticular changes by the last follow-up. Conclusions Intraoperative vaulting correlates well with postoperative vaulting and can aid in on-table detection of extremes of vaulting and decision-making. It enhances the safety of the surgical procedure by providing a real-time display of the intraoperative manipulations.
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Haworth, Jeffrey, and Richard Bruce. "Australian states and Northern Territory acreage update." APPEA Journal 54, no. 1 (2014): 421. http://dx.doi.org/10.1071/aj13042.
Повний текст джерелаАнотація:
It is encouraging to note that a number of international oil companies (IOCs) have taken an interest in Australian onshore exploration, including the following: Bowen-Surat Basin—BG, ConocoPhillips, CNOOC, PetroChina, Sinopec, KOGAS, Mitsui, Petronas, Shell, and Total.Canning Basin—Mitsubishi, ConocoPhillips, Hess, PetroChina, and Apache.Cooper-Eromanga Basin—BG, and Chevron.Galilee Basin—CNOOC.Georgina Basin—Statoil, and Total. There is now greater interest in Australian onshore exploration, including in a number of sedimentary basins that have previously largely been overlooked. New views on geology and the development of a commercial shale and tight gas sector in the US have prompted a reassessment of onshore petroleum potential, especially in SA, the NT and WA. Access to onshore acreage in Australia for petroleum exploration is, in most jurisdictions, by means of a formal release process with a work program bidding system. Acreage that is being made available for exploration will generally be accompanied by information regarding its geological setting and petroleum prospectivity. Previous exploration activity may be summarised (including information in relation to the amount of pre-existing data available to applicants for acreage), and relevant maps and figures may be included. The following is a compilation of material supplied by the states and NT in relation to onshore acreage being made available for petroleum exploration.
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Horwood, James, Fayaz Akbar, Katherine Davis, and Richard Morgan. "Prospective evaluation of a selective approach to cholangiography for suspected common bile duct stones." Annals of The Royal College of Surgeons of England 92, no. 3 (April 2010): 206–10. http://dx.doi.org/10.1308/003588410x12628812458293.
Повний текст джерелаАнотація:
INTRODUCTION Common bile duct (CBD) stones can cause serious morbidity or mortality, and evidence for them should be sought in all patients with symptomatic gallstones undergoing cholecystectomy. Routine intra-operative cholangiography (IOC) involves a large commitment of time and resources, so a policy of selective cholangiography was adopted. This study prospectively evaluated the policy of selective cholangiography for patients suspected of having choledocholithiasis, and aimed to identify the factors most likely to predict the presence of CBD stones positively. PATIENTS AND METHODS Data from 501 consecutive patients undergoing laparoscopic cholecystectomy (LC) for symptomatic gallstones, of whom 166 underwent IOC for suspected CBD stones, were prospectively collected. Suspicion of choledocholithiasis was based upon: (i) deranged liver function tests (past or present); (ii) history of jaundice (past or present) or acute pancreatitis; (iii) a dilated CBD or demonstration of CBD stones on imaging; or (iv) a combination of these factors. Patient demographics, intra-operative findings, complications and clinical outcomes were recorded. RESULTS Sixty-four cholangiograms were positive (39%). All indications for cholangiogram yielded positive results. Current jaundice yielded the highest positive predictive value (PPV; 86%). A dilated CBD on pre-operative imaging gave a PPV of 45% for CBD calculi; a history of pancreatitis produced a 26% PPV for CBD calculi. Patients with the presence of several factors suggestive of CBD stones yielded higher numbers of positive cholangiograms. Of the 64 patients having a laparoscopic common bile duct exploration (LCBDE), four (6%) required endoscopic retrograde cholangiopancreatography (ERCP) for retained stones (94% successful surgical clearance of the common bile duct) and one (2%) for a bile leak. Of the 335 patients undergoing LC alone, three (0.9%) re-presented with a retained stone, requiring intervention. There were 12 (7%) requiring conversion to open operation. CONCLUSIONS A selective policy for intra-operative cholangiography yields acceptably high positive results. Pre-operatively, asymptomatic bile duct stones rarely present following LC; thus, routine imaging of the biliary tree for occult calculi can safely be avoided. Therefore, a rationing approach to the use of intra-operative imaging based on the pre-operative indicators presented in this paper, successfully identifies those patients with bile duct stones requiring exploration. Laparoscopic bile duct exploration, performed by an experienced laparoscopic surgeon, is a safe and effective method of clearing the bile duct of calculi, with minimal complications, avoiding the necessity for an additional intervention and prolonged hospital stay.
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Maestro, Antonio, David Varillas-Delgado, Esther Morencos, Jorge Gutiérrez-Hellín, Millán Aguilar-Navarro, Gonzalo Revuelta, and Juan Del Coso. "Injury Incidence Increases after COVID-19 Infection: A Case Study with a Male Professional Football Team." International Journal of Environmental Research and Public Health 19, no. 16 (August 18, 2022): 10267. http://dx.doi.org/10.3390/ijerph191610267.
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Background: The SARS-CoV-2 virus disease has caused numerous changes in sports routines in the last two years, showing the influence on an increase in sports injuries. The aim of this study was to prospectively analyze the incidence and characteristics of injuries in male professional football players diagnosed with COVID-19 when they return to play after recovering from this illness. Methods: Injury characteristics of professional male football players were recorded for the 2020–2021 season following the international consensus statement from the International Olympic Committee (IOC). SARS-CoV-2 infection in the football players was certified by PCR analysis. Injury epidemiology was compared in players infected by the SARS-CoV-2 virus before and after being diagnosed with COVID-19. Results: 14 players (53.8%) were diagnosed with COVID-19 during 2020–2021 season and 12 (46.2%) were not infected (controls). Only three (21.4%) had suffered an injury before being diagnosed with COVID-19. Eleven players (78.6%) had injuries after being diagnosed with COVID-19 (p < 0.001). Among the players diagnosed with COVID-19, injury incidence increased on their return to play after the infection (3.8 to 12.4 injuries/1000 h of exposure, p < 0.001). Additionally, injury incidence during training (10.6 vs. 5.1 injuries/1000 h of exposure, p < 0.001) and matches (56.3 vs. 17.6 injuries/1000 h of exposure, p < 0.001) was ~two-fold higher on return to play after COVID-19 compared to controls (33.4 vs. 17.6 injuries/1000 h of exposure, respectively, p < 0.001). Conclusions: Injury incidence in professional football players who had been infected by the SARS-CoV-2 virus significantly increased compared to the injury rates that these same players had prior to the illness. Additionally, the injury incidence was higher when compared to players who were not infected by the SARS-CoV-2 virus during the season, especially during matches.
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Hatem, Fady, Sam Mostafa, Jenny Thomas, and Ahmad Nassar. "SP6.1.6 Rule of systematic intraoperative cholangiogram in patients undergoing emergency cholecystectomy." British Journal of Surgery 108, Supplement_7 (October 1, 2021). http://dx.doi.org/10.1093/bjs/znab361.133.
Повний текст джерелаАнотація:
Abstract Aims Incidence of gall stone disease is estimated at 10-15%of population. Intraoperative cholangiography (IOC) diagnose choledocholithiasis, delineates the anatomy of the biliary ducts, facilitate the dissection and reduces injuries. Our aim is to assess the feasibility and role of IOC and the incidence of choledocholithiasis in acute cholecystitis (ACC). Methods Retrospective analysis of prospectively collected data for patients admitted with ACC and undergoing same-hospital-stay laparoscopic cholecystectomy (LC). IOC was systematically attempted in all cases. Results 475cases included. Female to male ratio1.9:1. Conversion to open was done in 3 cases. Preoperative cholelithiasis was confirmed in 439cases versus 34cases with no stones. USS CBD abnormality (dilated or contain stone) found in 53 cases, out of which 8(15%) cases had CBD stones. Jaundice was found in 69cases, where 25(39%) cases had confirmed choledocholithiasis. IOC was successful in all cases except one. Abnormal IOC was found in 99(21%) cases. Of those; CBD stones were confirmed in 76 (77%) cases regardless the presence of cholelithisasis on USS. Empyema was found in 237 cases and it was associated with higher risk of abnormal IOC in 59(25%) cases where CBD stones were confirmed in 45(76%) cases. Cystic duct (CD) stones found in 80cases, of those 27(34%)cases had choledocholithiasis. Conclusions Females have double the risk of ACC. Preoperative jaundice and CD stones are stronger indicators than CBD diameter for presence of choledocholithiasis. The incidence of choledocholithiasis in ACC is (20-25%) regardless the presence of gall stones on USS. IOC is feasible and highly recommended in emergency LC.
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Ivanecz, Arpad, Irena Plahuta, Matej Mencinger, Iztok Perus, Tomislav Magdalenic, Spela Turk, and Stojan Potrc. "The learning curve of laparoscopic liver resection utilising a difficulty score." Radiology and Oncology, September 6, 2021. http://dx.doi.org/10.2478/raon-2021-0035.
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Abstract Background This study aimed to quantitatively evaluate the learning curve of laparoscopic liver resection (LLR) of a single surgeon. Patients and methods A retrospective review of a prospectively maintained database of liver resections was conducted. 171 patients undergoing pure LLRs between April 2008 and April 2021 were analysed. The Halls difficulty score (HDS) for theoretical predictions of intraoperative complications (IOC) during LLR was applied. IOC was defined as blood loss over 775 mL, unintentional damage to the surrounding structures, and conversion to an open approach. Theoretical association between HDS and the predicted probability of IOC was utilised to objectify the shape of the learning curve. Results The obtained learning curve has resulted from thirteen years of surgical effort of a single surgeon. It consists of an absolute and a relative part in the mathematical description of the additive function described by the logarithmic function (absolute complexity) and fifth-degree regression curve (relative complexity). The obtained learning curve determines the functional dependency of the learning outcome versus time and indicates several local extreme values (peaks and valleys) in the learning process until proficiency is achieved. Conclusions This learning curve indicates an ongoing learning process for LLR. The proposed mathematical model can be applied for any surgical procedure with an existing difficulty score and a known theoretically predicted association between the difficulty score and given outcome (for example, IOC).
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ain, Noor Ul, Saira Bibi, Ian Tait, and Samer Zino. "P-BN59 Danger is there, do we want to know about it? Routine intra operative cholangiography highlights dangerous biliary anatomy for safer cholecystectomy." British Journal of Surgery 108, Supplement_9 (December 1, 2021). http://dx.doi.org/10.1093/bjs/znab430.056.
Повний текст джерелаАнотація:
Abstract Background Normal biliary anatomy is uncommon. Different classification for biliary anatomy has been described, with Huang Types A4 & A5 of great interest for laparoscopic cholecystectomy (LC) due to the proximity of aberrant bile duct to Cystic duct (CD). These types of dangerous anatomy might contribute to bile duct injury. This study aims to analyse the prevalence of dangerous biliary anatomy. Methods Prospectively collected data for all patients who underwent laparoscopic cholecystectomy was analysed. All LC were performed by single surgeon or under his direct supervision, between 01/07/2020 and 20/08/2021. Index admission and single session management of cholelithiasis disease with routine Laparoscopic cholecystectomy + intra operative cholangiography (IOC) +/- LCBD exploration were standard practice. Results Laparoscopic cholecystectomy was performed in 137 patients. Mean age was 56y (17-84). 62% were females. 66% of Laparoscopic cholecystectomies were emergency. IOC was performed in 92% of cases. Abnormal biliary anatomy was found in 54% : Huang A1 - 48%, A2 - 29%, A3 - 12%, A4 - 9.7% and A5 - 0.7%. Dangerous anatomy (A4 and A5) was found in 10.5%, 78 % were females. Female with dangerous anatomy were younger than males 49 y, 60y respectively. Nassar difficulty grading for dangerous anatomy was as follows: G2 28%, G3 42% and G3 28% Abnormal cholangiogram was found in 48%, due to filling defect in 58%, no contrast flow into duodenum in 4%, Cystic duct stone in 4%, and short CD in 8%. CBD stones were treated using transcystic approach in 92% of cases. No intra-operative or post operative complications were recorded for patients with dangerous anatomy. Conclusions This study demonstrates that dangerous biliary anatomy, that could lead to bile duct injury is relatively common, occurring in 10.7% of LCs. Routine intra-operative cholangiography highlights these high-risk variations in biliary anatomy and may prevent inadvertent bile duct injury in such cases.
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Nassar, Ahmad H. m., Rhona Kilpatrick, Mahmoud Sallam, and Kiren Ali. "O-EGS05 The Prevalence of Bile Duct Stones in Patients Presenting with Acute Pancreatitis vs. Jaundice in a 5774 patient series. The Case for Single Session Surgical Management." British Journal of Surgery 108, Supplement_9 (December 1, 2021). http://dx.doi.org/10.1093/bjs/znab429.019.
Повний текст джерелаАнотація:
Abstract Background There is increasing evidence that single session laparoscopic cholecystectomy with cholangiography and, when necessary and available, bile duct exploration offers optimal clinical outcomes and superior cost benefits to patients with suspected bile duct stones. There is a perception that preoperative endoscopic clearance of bile duct stones is necessary in patients presenting with pancreatitis and jaundice. However, most patients do not have severe disease and are fit for index admission surgical management. We aim to study the prevalence of bile duct stones in pancreatitis vs. jaundice and evaluate this management approach with regards to preoperative and operative parameters and postoperative outcomes. Methods Analysis of prospectively maintained database of 5774 consecutive laparoscopic cholecystectomies, cholangiography(IOC) with or without bile duct exploration was undertaken. Patients with suspected bile duct stones are referred to one firm with an intention of single surgical treatment in the index admission. Data of patients presenting with acute pancreatitis and obstructive jaundice was extracted. In the absence of suspected malignancy there was a limited role for preoperative MRCP and ERCP. The incidence of confirmed CBD stones requiring exploration, type of exploration, morbidity, re-operations and readmissions, hospital stay, number of episodes, and presentation to resolution intervals were compared in the two groups. Results Conclusions Single session surgical treatment of patients with acute pancreatitis and jaundice by specialist firms in the index admission (89% and 86% if previous admissions by other units is excluded) offers many advantages. MRCP and ERCP utilisation is minimised in favour of IOC; two thirds of pancreatitis patients and one third of jaundiced patients have no CBD stones. Simple transcystic explorations deals with most stones in both groups. The morbidity, open conversion, readmissions, retained stones and re-operations are low. Total hospital stay, number of treatment episodes and presentation to resolution are optimised and should persuade surgeons to avoid subjecting patients to multiple treatments.
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Ibrahim, Basil, Sophie Tait, and Ahmad Nassar. "WE2.11 Optimal Utilisation of Cross-Sectional Imaging in Patients with Painful Jaundice Undergoing Bile Duct Exploration or Conservative Management for Suspected Bile Duct Stones on a Specialist Unit." British Journal of Surgery 109, Supplement_5 (August 1, 2022). http://dx.doi.org/10.1093/bjs/znac248.108.
Повний текст джерелаАнотація:
Abstract Aim Laparoscopic management of bile duct stones relies on intraoperative cholangiography, optimising utilisation of preopertative imaging. This study aims to determine whether such a policy is justifiable in jaundiced patients over 50 years of age with no risk factors for malignancy. Methods Prospectively collected data of patients presenting with gall stones and painful jaundice undergoing biliary surgery or treated conservatively was analysed. The presentation, preoperative imaging, cholangiography/ choledochoscopy findings and postoperative outcomes were recorded. Patients with risk factors for malignancy were excluded. Results 1220 jaundiced patients over 50 years were referred over 24 years. 684 underwent surgery having had CT in 15.3%, MRCP 10% and ERCP 2.5%. 536 unfit patients were managed conservatively (CT 15.7%, MRCP 27.8% and ERCP 29.5%). Most had these investigations under the care of other departments prior to referral. 21/684 (3%) presenting with painful jaundice associated with acute cholecystitis or bile duct stones and no risk factors for malignancy were diagnosed with malignancy on IOC and choledochoscopy. 7 patients had preoperative cross sectional imaging, one with ERCP showing no evidence of malignancy. The remaining 14 patients underwent postoperative imaging; 7 had radiologically undetectable disease, 6 had advanced disease and only one was suitable for a “curative resection”. 21/536 (3.9%) cancers were diagnosed in patients who were treated conservatively. Conclusion Based on the little diagnostic yield of curable biliary malignancies, a policy of no cross sectional imaging in patients with obstructive jaundice and no risk of malignancy is justifiable in units adopting single session management of bile duct stones.