Статті в журналах: "Laser ablation tomography"

1

Góra, Michalina, Piotr Targowski, Antoni Rycyk, and Jan Marczak. "Varnish Ablation Control by Optical Coherence Tomography." Laser Chemistry 2006 (January 14, 2006): 1–7. http://dx.doi.org/10.1155/2006/10647.

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Preliminary results of the application of optical coherence tomography (OCT), in particular in its spectral mode (SOCT) to the control of a varnish ablation process, are presented. Examination of the ablation craters made with an Er:YAG laser allows optimization of the laser emission parameters controlling fluence with respect to efficiency and safety of the ablation process. Results of measurements of ablation crater depth as a function of the number of pulses for a given fluence are presented for selected resins. This validates the applicability of SOCT to calibration of ablation conditions for the particular laser-varnish-paint layer combinations, and of its usage in planning the varnish ablation procedure. These results also imply that a review of conventional ablation thresholds is called for. Applicability of the SOCT technique to contemporaneous in situ monitoring of the range of varnish ablation is discussed.

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2

Cetin, Cigdem, Sandra Drusová, Arsham Hamidi, Georg Rauter, Philippe Cattin, Azhar Zam, and Ferda Canbaz. "Bone ablation using a Ho:YAG laser." Current Directions in Biomedical Engineering 8, no. 2 (August 1, 2022): 580–83. http://dx.doi.org/10.1515/cdbme-2022-1148.

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Abstract This study aimed to optimize the ablation depth and duration at a fixed energy using a Ho:YAG laser, considering fiber delivery applications. According to the measurements performed with an optical coherence tomography system, we obtained depths of about 1.4 mm with 500 mJ/pulse applied energy when moving the laser along a 1 cm line for 60 s (corresponding to ~50 pulses per position). Coupling this laser into a flexible fiber (θ= 250 μm) will be the next step for future minimal-invasive bone ablation trials. Furthermore, deeper ablation (~1.5 mm) was also achieved with different energy levels on bone samples.

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3

Zhang, Yaokun, Tom Pfeiffer, Marcel Weller, Wolfgang Wieser, Robert Huber, Jörg Raczkowsky, Jörg Schipper, Heinz Wörn, and Thomas Klenzner. "Optical Coherence Tomography Guided Laser Cochleostomy: Towards the Accuracy on Tens of Micrometer Scale." BioMed Research International 2014 (2014): 1–10. http://dx.doi.org/10.1155/2014/251814.

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Lasers have been proven to be precise tools for bone ablation. Applying no mechanical stress to the patient, they are potentially very suitable for microsurgery on fragile structures such as the inner ear. However, it remains challenging to control the laser-bone ablation without injuring embedded soft tissue. In this work, we demonstrate a closed-loop control of a short-pulsed CO2laser to perform laser cochleostomy under the monitoring of an optical coherence tomography (OCT) system. A foresighted detection of the bone-endosteum-perilymph boundary several hundred micrometers before its exposure has been realized. Position and duration of the laser pulses are planned based on the residual bone thickness distribution. OCT itself is also used as a highly accurate tracking system for motion compensation between the target area and the optics. Duringex vivoexperimental evaluation on fresh porcine cochleae, the ablation process terminated automatically when the thickness of the residual tissue layer uniformly reached a predefined value. The shape of the resulting channel bottom converged to the natural curvature of the endosteal layer without injuring the critical structure. Preliminary measurements in OCT scans indicated that the mean absolute accuracy of the shape approximation was only around 20 μm.

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4

Ventura, Bruna V., Haroldo V. Moraes, Newton Kara-Junior, and Marcony R. Santhiago. "Role of Optical Coherence Tomography on Corneal Surface Laser Ablation." Journal of Ophthalmology 2012 (2012): 1–6. http://dx.doi.org/10.1155/2012/676740.

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This paper focuses on reviewing the roles of optical coherence tomography (OCT) on corneal surface laser ablation procedures. OCT is an optical imaging modality that uses low-coherence interferometry to provide noninvasive cross-sectional imaging of tissue microstructurein vivo.There are two types of OCTs, each with transverse and axial spatial resolutions of a few micrometers: the time-domain and the fourier-domain OCTs. Both have been increasingly used by refractive surgeons and have specific advantages. Which of the current imaging instruments is a better choice depends on the specific application. In laserin situkeratomileusis (LASIK) and in excimer laser phototherapeutic keratectomy (PTK), OCT can be used to assess corneal characteristics and guide treatment decisions. OCT accurately measures central corneal thickness, evaluates the regularity of LASIK flaps, and quantifies flap and residual stromal bed thickness. When evaluating the ablation depth accuracy by subtracting preoperative from postoperative measurements, OCT pachymetry correlates well with laser ablation settings. In addition, OCT can be used to provide precise information on the morphology and depth of corneal pathologic abnormalities, such as corneal degenerations, dystrophies, and opacities, correlating with histopathologic findings.

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5

Roszkowska, Anna M., Giovanni W. Oliverio, Giuseppe A. Signorino, Mario Urso, and Pasquale Aragona. "Severe Corneal Morphological Alterations after Excimer Laser Surface Ablation for a High Astigmatism." Case Reports in Ophthalmology 12, no. 2 (June 11, 2021): 492–96. http://dx.doi.org/10.1159/000516311.

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We report long-term alterations of anterior corneal stroma after excimer laser surface ablation for a high astigmatism. The patient claimed progressive visual loss in his right eye (RE) during the last 3 years after bilateral laser-assisted subepithelial keratectomy (LASEK) surgery. His examination comprised visual acuity (UDVA and CDVA), slit-lamp examination, corneal topography and tomography, AS-OCT, and confocal microscopy. The UDVA was 0.1 in his RE and 1.0 in the left eye. The CDVA in the RE was 0.8. The slit-lamp examination showed a stromal lesion in the inferior paracentral corneal zone, with multiple vertical tissue bridges and severe thinning. Corneal topography and tomography showed central flattening with inferior steepening and severe alteration in elevation maps. AS-OCT showed void areas in the anterior stroma with thinning of the underlying tissue, and confocal images were not specific. In this case, progressive corneal steepening and thinning that manifest topographically as inferior ectasia occurred in correspondence to the singular stromal alterations after LASEK.

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6

Korzeniewska, Ewa, Jarosław Gocławski, Joanna Sekulska-Nalewajko, Maria Walczak, and Bożena Wilbik-Hałgas. "Changes in Fabric Surface Pilling under Laser Ablation." Sensors 20, no. 20 (October 15, 2020): 5832. http://dx.doi.org/10.3390/s20205832.

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Textiles require finishing to improve their usability and functionality but in the first place, to reduce of pilling tendency, which affects all kinds of synthetic and natural fabrics. Several laser ablation tests have been applied to the selected fabrics with different chemical composition to reveal the impact of this process on the pilling behavior. To reflect the pilling changes, two textural descriptors have been proposed to textile images obtained with optical coherence tomography (OCT). They showed the trend to reduce values with increasing laser power applied to the tested fabrics. It has been demonstrated, that in the case of textiles based on polyester threads, laser modification of the product surface led to a significant reduction in their tendency for pilling.

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7

Sachdev, Harikrishan S., Bhairav Patel, Mark McManis, Mark Lee, and Dave F. Clarke. "Comparing Single-Photon Emission Computed Tomography (SPECT), Electroencephalography (EEG), and Magneto-encephalography (MEG) Seizure Localizations in Pediatric Cases of Laser Ablation." Journal of Child Neurology 34, no. 6 (February 12, 2019): 303–8. http://dx.doi.org/10.1177/0883073818822353.

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Intractable epilepsy may have a more severe effect on children in comparison to adults because the motor, sensorial, and cognitive functions of children are still undergoing development. For this same reason, however, children maintain a greater potential for recovery from intractable epilepsy because of the remaining cerebral plasticity. Thus, after 2 unsuccessful antiepileptic medications, surgical intervention is recommended. Pre-surgical localization of the epileptogenic zone increases seizure-freedom post-surgery by 200% to 300%. Single-photon emission computed tomography (SPECT) is commonly used, with magneto-encephalography (MEG) and electroencephalography (EEG), to localize the epileptogenic zone, because it localizes cerebral blood flow. There is limited research in the efficacy of SPECT localization in pediatric pharmacoresistant epilepsy. Therefore, the objective of this study was to determine the efficacy of SPECT in it’s ability to localize the epileptogenic zone in laser ablation cases of pediatric pharmacoresistant epilepsy. Out of 122 SPECTs conducted at Dell Children’s Medical Center from July 2010 to January 2015, 12 underwent laser ablation. In the 12 cases of laser ablation, SPECT displayed more sensitivity and specificity than EEG and more specificity than MEG when held against the laser ablation outcomes. This study further proves that SPECT is efficacious in epileptogenic zone localization of pediatric pharmacoresistant epilepsy.

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8

Lee, Jungnam, Youjeong Seo, Van Gia Truong, Hye Jung Jeong, Jung-Hyun Lim, Seonghee Lim, Hyun Wook Kang, and Jin-Seok Park. "Endoscopic Ultrasound-Guided Pancreatic Interstitial Laser Ablation Using a Cylindrical Laser Diffuser: A Long-Term Follow-Up Study." Biomedicines 10, no. 11 (November 11, 2022): 2895. http://dx.doi.org/10.3390/biomedicines10112895.

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Background and Aims: Local ablative treatment is another option for improving outcomes and has been evaluated for locally advanced pancreatic cancer. We previously suggested endoscopic ultrasound (EUS)-guided interstitial laser ablation using a cylindrical laser diffuser (CILA) might be a feasible therapeutic option based on experiments performed on pancreatic cancer cell lines and porcine model with a short follow-up (3 days). The aim of this study was to investigate the safety of EUS-CILA performed using optimal settings in porcine pancreas with a long-term follow-up (2 weeks). Methods: EUS-CILA (laser energy of 450 J; 5 W for 90 s) was applied to normal pancreatic tissue in porcine (n = 5) under EUS guidance. Animals were observed clinically for 2 weeks after EUS-CILA to evaluate complications. Computed tomography and laboratory tests were carried out to evaluate safety. Two weeks after EUS-CILA, all pigs were sacrificed, and histopathological safety and efficacy evaluations were conducted. Results: EUS-CILA was technically successful in all five cases. No major complications occurred during the follow-up period. Body weight of porcine did not change during the study period without any significant change in feed intake. Animals remained in excellent condition throughout the experimental period, and laboratory tests and computed tomography (CT) scans provided no evidence of a major complication. Histopathological evaluation showed complete ablation in the ablated area with clear delineation of surrounding normal pancreatic tissue. Mean ablated volume was 55.5 mm2 × 29.0 mm and mean ablated areas in the pancreatic sections of the five pigs were not significantly different (p = 0.368). Conclusions: In conclusion, our experimental study suggests that EUS-CILA is safe and has the potential to be an effective local treatment modality. No major morbidity or mortality occurred during the study period. Further evaluations are warranted before clinical application.

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9

Lee, Ho, Robert T. Ryan, Jeehyun Kim, Bernard Choi, Navanit V. Arakeri, Joel M. H. Teichman, and A. J. Welch. "Dependence of Calculus Retropulsion Dynamics on Fiber Size and Radiant Exposure During Ho:YAG Lithotripsy." Journal of Biomechanical Engineering 126, no. 4 (August 1, 2004): 506–15. http://dx.doi.org/10.1115/1.1786297.

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During pulsed laser lithotripsy, the calculus is subject to a strong recoil momentum which moves the calculus away from laser delivery and prolongs the operation. This study was designed to quantify the recoil momentum during Ho:YAG laser lithotripsy. The correlation among crater shape, debris trajectory, laser-induced bubble and recoil momentum was investigated. Calculus phantoms made from plaster of Paris were ablated with free running Ho:YAG lasers. The dynamics of recoil action of a calculus phantom was monitored by a high-speed video camera and the laser ablation craters were examined with Optical Coherent Tomography (OCT). Higher radiant exposure resulted in larger ablation volume (mass) which increased the recoil momentum. Smaller fibers produced narrow craters with a steep contoured geometry and decreased recoil momentum compared to larger fibers. In the presence of water, recoil motion of the phantom deviated from that of phantom in air. Under certain conditions, we observed the phantom rocking towards the fiber after the laser pulse. The shape of the crater is one of the major contributing factors to the diminished recoil momentum of smaller fibers. The re-entrance flow of water induced by the bubble collapse is considered to be the cause of the rocking of the phantom.

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10

Smith, Aaron Asael, Rui Li, and Zion Tsz Ho Tse. "Laser Ablation in Magnetic Resonance Imaging/Computed Tomography Environment: A Review." Imaging and Intervention 1, no. 3 (May 10, 2022): 66–73. http://dx.doi.org/10.5152/iai.2022.21024.

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11

Bagayev, Sergey N., Valentin M. Gelikonov, Grigory V. Gelikonov, Evgeny S. Kargapoltsev, Roman V. Kuranov, Alexander M. Razhev, Ilya V. Turchin, and Andrey A. Zhupikov. "Optical coherence tomography for in situ monitoring of laser corneal ablation." Journal of Biomedical Optics 7, no. 4 (2002): 633. http://dx.doi.org/10.1117/1.1501891.

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12

Ohmi, Masato, Manabu Tanizawa, Atsushi Fukunaga, and Masamitsu Haruna. "In-situ Observation of Tissue Laser Ablation Using Optical Coherence Tomography." Optical and Quantum Electronics 37, no. 13-15 (December 2005): 1175–83. http://dx.doi.org/10.1007/s11082-005-4189-2.

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13

Strock, Christopher F., Hannah M. Schneider, Tania Galindo-Castañeda, Benjamin T. Hall, Bart Van Gansbeke, Diane E. Mather, Mitchell G. Roth, et al. "Laser ablation tomography for visualization of root colonization by edaphic organisms." Journal of Experimental Botany 70, no. 19 (June 13, 2019): 5327–42. http://dx.doi.org/10.1093/jxb/erz271.

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Abstract Soil biota have important effects on crop productivity, but can be difficult to study in situ. Laser ablation tomography (LAT) is a novel method that allows for rapid, three-dimensional quantitative and qualitative analysis of root anatomy, providing new opportunities to investigate interactions between roots and edaphic organisms. LAT was used for analysis of maize roots colonized by arbuscular mycorrhizal fungi, maize roots herbivorized by western corn rootworm, barley roots parasitized by cereal cyst nematode, and common bean roots damaged by Fusarium. UV excitation of root tissues affected by edaphic organisms resulted in differential autofluorescence emission, facilitating the classification of tissues and anatomical features. Samples were spatially resolved in three dimensions, enabling quantification of the volume and distribution of fungal colonization, western corn rootworm damage, nematode feeding sites, tissue compromised by Fusarium, and as well as root anatomical phenotypes. Owing to its capability for high-throughput sample imaging, LAT serves as an excellent tool to conduct large, quantitative screens to characterize genetic control of root anatomy and interactions with edaphic organisms. Additionally, this technology improves interpretation of root–organism interactions in relatively large, opaque root segments, providing opportunities for novel research investigating the effects of root anatomical phenes on associations with edaphic organisms.

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14

Boppart, Stephen A., Juergen Herrmann, Costas Pitris, Debra L. Stamper, Mark E. Brezinski, and James G. Fujimoto. "High-Resolution Optical Coherence Tomography-Guided Laser Ablation of Surgical Tissue." Journal of Surgical Research 82, no. 2 (April 1999): 275–84. http://dx.doi.org/10.1006/jsre.1998.5555.

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15

Kaul, David, Oriane Bonhomme, Phillip Schwabe, Bernhard Gebauer, and Florian Streitparth. "Osteoid Osteoma with a Multicentric Nidus: Interstitial Laser Ablation under MRI Guidance." Case Reports in Orthopedics 2013 (2013): 1–5. http://dx.doi.org/10.1155/2013/254825.

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Osteoid osteoma (OO) is a common benign tumor of the bone and is typically treated by thermal ablation with computed tomography (CT) guidance. Only a few cases of multicentric OO have been described. We here report the case of an 11-year-old boy with multicentric OO of the right femur treated with laser ablation under open high-field MRI guidance. The steps of the interventional MRI procedure are described, discussing the benefits and disadvantages of MRI versus CT guidance especially with regard to younger patients.

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16

Snetkov, A. I., N. Yu Gruzdev, S. Yu Batrakov, A. D. Akinshina, and I. M. Dan. "The first experience of applying laser ablation in patients with benign tumors, tumor-like and inflammatory diseases of the skeleton." Laser Medicine 24, no. 4 (April 28, 2021): 37–42. http://dx.doi.org/10.37895/2071-8004-2020-24-4-37-42.

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The researchers discuss the first experience of treating 9 pediatric patients with osteoid osteoma (3), primary chronic osteomyelitis (4) and aneurysmal cysts (2). Selected patients had complex treatment which included unloading of the diseased segment of the skeleton and laser ablation of the pathological focus. Laser ablation was done with medical laser «AZOR-ALM», emitting light at wavelength 1.55 μm. Registration certificate No. RZN 2015/2720 of Roszdravnadzor. Manufacturer – LLC «AZOR» (Moscow). Small tumors and inflammatory diseases of the skeleton were surgically treated with high-level laser light in the computed tomography room. Patients with lesions of lower extremities and pelvis previously had spinal anesthesia. If a pathologic focus was located in bones of upper extremities, regional brachial plexus blockage was preferable. In all cases, positive outcomes were seen. Follow-up lasted for 6 months.

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Gómez-Varela, Ana I., Raúl Sanchez, Bastián Carnero, Luis Diaz-Gomez, M. Teresa Flores-Arias, and Carmen Bao-Varela. "Subaquatic indirect laser ablation technique for glass processing." Optics Express 30, no. 21 (September 26, 2022): 37536. http://dx.doi.org/10.1364/oe.463803.

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Subaquatic indirect Laser-Induced Plasma-Assisted Ablation (SLIPAA) is proposed as a laser-based technique for glass processing. In this configuration, a water layer is added between a metallic target and a soda-lime glass substrate, so the processing of the glass is due to a combination of the ablation mechanism, the shock waves, and the cavitation bubbles. Thus, this method makes it possible to produce higher depth structures than those performed up to now by other standard laser techniques based on ablation, achieving structures in glass with rectangular cross-sectional profiles. Channels of 1 mm width are fabricated, reaching an average maximal depth value of almost 1400 µm at 30 passes of the laser beam while keeping the focal position fixed. Furthermore, the difference between processing the material with and without the addition of the water layer is presented. The influence of the processing parameters on the shape and quality of the fabricated structures is studied by optical and confocal microscopy, microcomputed tomography, and scanning electron microscopy. Compositional analysis of the glass is performed by energy dispersive X-ray technique to assess the transference of material from the metallic target to the fabricated channels. Deeper and more complex structures are obtained by refocusing the laser beam on the target and adding a pulsed flowing water film.

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18

Liang, Shanshan, Xinyu Li, Jiajing Kang, Jiebin Zou, Faya Liang, and Jun Zhang. "Integrated Multifunctional Laryngoscope for Medical Diagnosis and Treatment." Applied Sciences 10, no. 21 (October 25, 2020): 7491. http://dx.doi.org/10.3390/app10217491.

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Laryngeal lesions can cause great inconvenience to patients. Early diagnosis and corresponding treatments are critical to the survival of patients. However, the diagnosis and precise removal of tumors remain a challenge under the use of a white light laryngoscope. In this work, an integrated, multifunctional laryngoscope was designed and tested for the imaging evaluation and precision laser surgery for laryngeal tissue. This integrated diagnostic and therapeutic endoscopic system included two imaging modes (i.e., optical coherence tomography and white light endoscopy) and a laser ablation treatment mode. The endoscope had a common-path design to ensure that the same position could be imaged and treated simultaneously. The ex vivo porcine larynx experimental results showed that the system imaging modes could simultaneously acquire both superficial and cross-sectional images of the sample tissue, and the ablation treatment could be performed under imaging guidance. This multifunctional laryngoscope has great potential for the early diagnosis of and accurate laser ablation surgery for laryngeal tumors.

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19

Seifabadi, Reza, Ming Li, Sheng Xu, Yue Chen, Alex Squires, Ayele Negussie, Ivane Bakhutashvili, et al. "MRI Robot for Prostate Focal Laser Ablation: An Ex Vivo Study in Human Prostate." Journal of Imaging 4, no. 12 (November 29, 2018): 140. http://dx.doi.org/10.3390/jimaging4120140.

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Purpose: A novel grid-template-mimicking MR-compatible robot was developed for in-gantry MRI-guided focal laser ablation of prostate cancer. Method: A substantially compact robot was designed and prototyped to meet in-gantry lithotomy ergonomics and allow for accommodation in the perineum. The controller software was reconfigured and integrated with the custom-designed navigation and multi-focal ablation software. Three experiments were conducted: (1) free space accuracy test; (2) phantom study under computed tomography (CT) guidance for image-guided accuracy test and overall workflow; and (3) magnetic resonance imaging (MRI)-guided focal laser ablation of an ex vivo prostate. The free space accuracy study included five targets that were selected across the workspace. The robot was then commanded five times to each target. The phantom study used a gel phantom made with color changing thermos-chromic ink, and four spherical metal fiducials were deployed with the robot. Then, laser ablation was applied, and the phantom was sliced for gross observation. For an MR-guided ex vivo test, a prostate from a donor who died of prostate cancer was obtained and multi-focally ablated using the system within the MRI gantry. The tissue was sliced after ablation for validation. Results: free-space accuracy was 0.38 ± 0.27 mm. The overall system targeting accuracy under CT guidance (including robot, registration, and insertion error) was 2.17 ± 0.47 mm. The planned ablation zone was successfully covered in both acrylamide gel phantom and in human prostate tissue. Conclusions: The new robot can accurately facilitate fiber targeting for MR-guided focal laser ablation of targetable prostate cancer.

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20

Cagini, Carlo, Marco Messina, Marco Lupidi, Francesco Piccinelli, Tito Fiore, Daniela Fruttini, and Leopoldo Spadea. "Posterior Corneal Surface Stability after Femtosecond Laser-Assisted Keratomileusis." Journal of Ophthalmology 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/184850.

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The purpose of this study was to evaluate posterior corneal surface variation after femtosecond laser-assisted keratomileusis in patients with myopia and myopic astigmatism. Patients were evaluated by corneal tomography preoperatively and at 1, 6, and 12 months. We analyzed changes in the posterior corneal curvature, posterior corneal elevation, and anterior chamber depth. Moreover, we explored correlation between corneal ablation depth, residual corneal thickness, percentage of ablated corneal tissue, and preoperative corneal thickness. During follow-up, the posterior corneal surface did not have a significant forward corneal shift: no significant linear relationships emerged between the anterior displacement of the posterior corneal surface and corneal ablation depth, residual corneal thickness, or percentage of ablated corneal tissue.

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21

Meyer, Carsten H., Stefan Mennel, and Jörg C. Schmidt. "Acute Keratoconus-Like Hydrops after Laser In Situ Keratomileusis." Journal of Ophthalmology 2009 (2009): 1–3. http://dx.doi.org/10.1155/2009/363482.

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Purpose.To demonstrate keratoconus-like hydrops after laser in situ keratomileusis (LASIK) by optical coherence tomography (OCT).Patient and Methods.A 21-year-old man received uneventful bilateral LASIK. On slit lamp examination or corneal topography there were no signs of fruste keratoconus. The preoperative corneal thickness was 587-m OD and the calculated ablation for two treatments was 114-m. Uneventful LASIK with an optical zone of 7 mm and an ablation of 89-m OD, and an ablation of 73-m OS was performed. Three years postoperatively, he complained about progressive myopia and impaired vision OD. His VA was hand motion OD and 20/20 OS.Results.OCT and light microscopy revealed an anterior corneal steepening and acute keratoconus-like excessive edematous swelling.Conclusion.The cornea is mechanically weakened after LASIK by the lamellar cut and tissue subtraction. Although the advocated minimal residual stromal bed thickness is 250-m, it may not be adequate to prevent progressive keratoconus-like hydrops in the selected cases.

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22

Simão, Teresa, Pascale Chevallier, Jean Lagueux, Marie-France Côté, Christoph Rehbock, Stephan Barcikowski, Marc-André Fortin, and Daniel Guay. "Laser-synthesized ligand-free Au nanoparticles for contrast agent applications in computed tomography and magnetic resonance imaging." Journal of Materials Chemistry B 4, no. 39 (2016): 6413–27. http://dx.doi.org/10.1039/c6tb01162d.

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Pulsed laser ablation in liquids (PLAL) has emerged as a new green chemistry method, advantageous to produce gold nanoparticles-based contrast agents with strong blood retention and for multimodal imaging.

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23

Holder, Daniel, Artur Leis, Matthias Buser, Rudolf Weber, and Thomas Graf. "High-quality net shape geometries from additively manufactured parts using closed-loop controlled ablation with ultrashort laser pulses." Advanced Optical Technologies 9, no. 1-2 (February 25, 2020): 101–10. http://dx.doi.org/10.1515/aot-2019-0065.

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AbstractAdditively manufactured parts typically deviate to some extent from the targeted net shape and exhibit high surface roughness due to the size of the powder grains that determines the minimum thickness of the individual slices and due to partially molten powder grains adhering on the surface. Optical coherence tomography (OCT)-based measurements and closed-loop controlled ablation with ultrashort laser pulses were utilized for the precise positioning of the LPBF-generated aluminum parts and for post-processing by selective laser ablation of the excessive material. As a result, high-quality net shape geometries were achieved with surface roughness, and deviation from the targeted net shape geometry reduced by 67% and 63%, respectively.

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Yuan, Wu, Defu Chen, Rachel Sarabia-Estrada, Hugo Guerrero-Cázares, Dawei Li, Alfredo Quiñones-Hinojosa, and Xingde Li. "Theranostic OCT microneedle for fast ultrahigh-resolution deep-brain imaging and efficient laser ablation in vivo." Science Advances 6, no. 15 (April 2020): eaaz9664. http://dx.doi.org/10.1126/sciadv.aaz9664.

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Current minimally invasive optical techniques for in vivo deep-brain imaging provide a limited resolution, field of view, and speed. These limitations prohibit direct assessment of detailed histomorphology of various deep-seated brain diseases at their native state and therefore hinder the potential clinical utilities of those techniques. Here, we report an ultracompact (580 μm in outer diameter) theranostic deep-brain microneedle combining 800-nm optical coherence tomography imaging with laser ablation. Its performance was demonstrated by in vivo ultrahigh-resolution (1.7 μm axial and 5.7 μm transverse), high-speed (20 frames per second) volumetric imaging of mouse brain microstructures and optical attenuation coefficients. Its translational potential was further demonstrated by in vivo cancer visualization (with an imaging depth of 1.23 mm) and efficient tissue ablation (with a 1448-nm continuous-wave laser at a 350-mW power) in a deep mouse brain (with an ablation depth of about 600 μm).

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White, N., K. Eder, J. Byrnes, J. M. Cairney, and I. E. McCarroll. "Laser ablation sample preparation for atom probe tomography and transmission electron microscopy." Ultramicroscopy 220 (January 2021): 113161. http://dx.doi.org/10.1016/j.ultramic.2020.113161.

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26

Pajic, Bojan, Brigitte Pajic-Eggspuehler, Zeljka Cvejic, Christian Rathjen, and Viktor Ruff. "First Clinical Results of a New Generation of Ablative Solid-State Lasers." Journal of Clinical Medicine 12, no. 2 (January 16, 2023): 731. http://dx.doi.org/10.3390/jcm12020731.

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In the early 2000s, solid-state lasers emerged as an alternative technology to excimer systems in refractive surgery. Despite some technological limits at the time, good clinical results could be achieved with solid-state laser systems. This prospective case series reports clinical outcomes of five eyes treated with a newly developed solid-state laser system (AquariuZ) in three patients. Patients underwent preoperative examination, including corneal topo-and tomography, aberrometry, and confocal microscopy. All patients received a femtosecond LASIK with the Ziemer LDV Z8, a refractive treatment with the AquariuZ solid-state ablation laser, and were then followed up for a period of up to 12 months. The applied aspheric optimized profiles did not induce higher-order aberrations nor spherical aberration in any of these operated subjects. No eye lost BCVA lines throughout the duration of the follow-up. Six months after surgery, the safety index of patient 1 was 5, and for patients 2 and 3, it equaled 1. Confocal laser microscopy imaging findings were comparable to those seen typically for excimer lasers. The obtained results are encouraging and confirm that the new solid-state laser system is safe.

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Zabotnov, Stanislav V., Anastasiia V. Skobelkina, Ekaterina A. Sergeeva, Daria A. Kurakina, Aleksandr V. Khilov, Fedor V. Kashaev, Tatyana P. Kaminskaya, et al. "Nanoparticles Produced via Laser Ablation of Porous Silicon and Silicon Nanowires for Optical Bioimaging." Sensors 20, no. 17 (August 28, 2020): 4874. http://dx.doi.org/10.3390/s20174874.

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Modern trends in optical bioimaging require novel nanoproducts combining high image contrast with efficient treatment capabilities. Silicon nanoparticles are a wide class of nanoobjects with tunable optical properties, which has potential as contrasting agents for fluorescence imaging and optical coherence tomography. In this paper we report on developing a novel technique for fabricating silicon nanoparticles by means of picosecond laser ablation of porous silicon films and silicon nanowire arrays in water and ethanol. Structural and optical properties of these particles were studied using scanning electron and atomic force microscopy, Raman scattering, spectrophotometry, fluorescence, and optical coherence tomography measurements. The essential features of the fabricated silicon nanoparticles are sizes smaller than 100 nm and crystalline phase presence. Effective fluorescence and light scattering of the laser-ablated silicon nanoparticles in the visible and near infrared ranges opens new prospects of their employment as contrasting agents in biophotonics, which was confirmed by pilot experiments on optical imaging.

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28

Verberne, Rick, David W. Saxey, Steven M. Reddy, William D. A. Rickard, Denis Fougerouse, and Chris Clark. "Analysis of Natural Rutile (TiO2) by Laser-assisted Atom Probe Tomography." Microscopy and Microanalysis 25, no. 2 (February 1, 2019): 539–46. http://dx.doi.org/10.1017/s1431927618015477.

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AbstractSince the introduction of laser-assisted atom probe, analysis of nonconductive materials by atom probe tomography (APT) has become more routine. To obtain high-quality data, a number of acquisition variables needs to be optimized for the material of interest, and for the specific question being addressed. Here, the rutile (TiO2) reference material ‘Windmill Hill Quartzite,’ used for secondary ion mass spectrometry U–Pb dating and laser-ablation inductively coupled plasma mass spectrometry, was analyzed by laser-assisted APT to constrain optimal running conditions. Changes in acquisition parameters such as laser energy and detection rate are evaluated in terms of their effect on background noise, ionization state, hit-multiplicity, and thermal tails. Higher laser energy results in the formation of more complex molecular ions and affects the ionization charge state. At lower energies, background noise and hit-multiplicity increase, but thermal tails shorten. There are also correlations between the acquisition voltage and several of these metrics, which remain to be fully understood. The results observed when varying the acquisition parameters will be discussed in detail in the context of utilizing APT analysis of rutile within geology.

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29

Kornilovskiy, I. M. "A new look at photoprotection and crosslinking in excimer laser vision correction." Modern technologies in ophtalmology, no. 5 (October 20, 2021): 132–36. http://dx.doi.org/10.25276/2312-4911-2021-5-132-136.

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Purpose. To develop approaches to excimer laser keratorefractive surgery based on a new view of the photoprotective function of the cornea, ablation-induced secondary radiation, photoprotective and side effects of crosslinking. Material and methods. The literature data and our own 32-year clinical observations of complications in excimer laser vision correction, methods of their treatment and prevention have been analyzed. Particular emphasis was placed on the analysis of works on photoprotection and crosslinking in photorefractive surgery. New approaches to excimer laser keratorefractive surgery are based on studies on the use of riboflavin for photoprotection and laser-induced crosslinking in corneal ablation (598 operations). Corneal crosslinking was assessed by computed keratotopography, optical coherence tomography, and corneal densitometry. Long-term results were followed up to 8 years. Results. Complications in excimer laser refractive surgery were associated with the development of dry eye syndrome, the formation of subepithelial or intrastromal fibroplasia. Ablation-induced secondary radiation played an important role in the development of complications of excimer laser refractive surgery. It negatively affected keratocytes, nerves and increased oxidative stress in the cornea. To protect against secondary radiation, a new technology of keratoablation with 0.25% isotonic riboflavin solution has been developed. This reduced oxidative stress and aseptic inflammatory response. According to OCT and densitometric studies, a decaying effect of crosslinking with the formation of a membrane structure on the ablation surface was revealed. Local photoprotection during ablation with riboflavin and the effect of crosslinking in combination with postoperative spectacle spectral UV photoprotection accelerated the stabilization of optical-refractive and visual results, increased the photoprotective and strength properties of the thinned cornea. This reduced the risks of keratoectasia and earlier development of cataracts. Conclusion. A new look at photoprotection and crosslinking in excimer laser refractive surgery provides for keratoablation with riboflavin in combination with postoperative spectacle spectral photoprotection from external UV radiation. Key words: excimer laser refractive surgery, dry eye, fibroplasia, keratoectasia, riboflavin, photoprotection, crosslinking.

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30

Kim, Suh Min. "Recurrent Varicose Vein after Endovenous Laser Ablation: Preoperative Evaluation with Computed Tomography Venography." Vascular Specialist International 36, no. 1 (March 31, 2020): 51–52. http://dx.doi.org/10.5758/vsi.2020.36.1.51.

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31

Tsai, Meng-Tsan, Wen-Ju Chen, Ting-Yen Tsai, Hsiang-Chieh Lee, Chun-Chieh Wang, and Ya-Ju Lee. "Optical Coherence Tomography/Angiography-Guided Tumor Ablation With a Continuous-Wave Laser Diode." IEEE Access 8 (2020): 43191–99. http://dx.doi.org/10.1109/access.2020.2976557.

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32

Watanabe, Satoshi, Takafumi Tsuji, Shinya Fujita, Soji Nishio, and Eisho Kyo. "A case of recurrent varicose veins due to the multiple fistulas from superficial femoral artery." SAGE Open Medical Case Reports 8 (January 2020): 2050313X2092642. http://dx.doi.org/10.1177/2050313x20926423.

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Recurrent varicose veins are considered to be caused by the recurrence of reflux but rarely may be secondary to other pathologies. A 39-year-old man complained of right lower leg skin pigmentation, pain and fatigue for several years. Duplex ultrasound revealed that the great saphenous vein diameter at the saphenofemoral junction level was 7.7 cm, and at the knee medial level was 14.4 cm. The reflux time at the proximal great saphenousvein level was 1.85 s. Endovenous laser ablation for dilated and refluxed great saphenous vein was performed. However, 1 year later, the symptoms recurred. Duplex ultrasound suspected abnormal arterial flow from the right superficial femoral artery to the recanalized segment of previously ablated great saphenous vein and anterior accessory saphenous vein. One month later, despite the successful re-endovenous laser ablation, the symptoms recurred. Computed tomography angiography showed three fistulous vessels from superficial femoral artery to anterior accessory saphenous vein. Combined treatments with endovenous laser ablation and coil embolization was performed. Ultimately, the fistulas were obliterated and the patient remained free of symptoms. Varicose veins due to the fistulas from superficial femoral artery are rare and difficult to diagnose but can be entirely treated with the percutaneous approach.

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33

Hahn, Jan, Manuela Moritz, Hannah Voß, Penelope Pelczar, Samuel Huber, and Hartmut Schlüter. "Tissue Sampling and Homogenization in the Sub-Microliter Scale with a Nanosecond Infrared Laser (NIRL) for Mass Spectrometric Proteomics." International Journal of Molecular Sciences 22, no. 19 (October 7, 2021): 10833. http://dx.doi.org/10.3390/ijms221910833.

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It was recently shown that ultrashort pulse infrared (IR) lasers, operating at the wavelength of the OH vibration stretching band of water, are highly efficient for sampling and homogenizing biological tissue. In this study we utilized a tunable nanosecond infrared laser (NIRL) for tissue sampling and homogenization with subsequent liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis for mass spectrometric proteomics. For the first time, laser sampling was performed with murine spleen and colon tissue. An ablation volume of 1.1 × 1.1 × 0.4 mm³ (approximately 0.5 µL) was determined with optical coherence tomography (OCT). The results of bottom-up proteomics revealed proteins with significant abundance differences for both tissue types, which are in accordance with the corresponding data of the Human Protein Atlas. The results demonstrate that tissue sampling and homogenization of small tissue volumes less than 1 µL for subsequent mass spectrometric proteomics is feasible with a NIRL.

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34

Kasyanenko, Ekaterina M., and Alexander I. Omelchenko. "Deformations of biological tissues with photothermal nanoparticles under laser irradiation." Yugra State University Bulletin 18, no. 1 (May 10, 2022): 21–31. http://dx.doi.org/10.18822/byusu20220121-31.

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In this work, optical coherence tomography (OCT) of gel phantoms and cartilage tissue of the joint impregnated with nanoparticles was performed under laser exposure to an erbium fiber laser with a wavelength of 1.56 m. Multifunctional "magnetite + gold" nanoparticles with a "core-shell" structure were obtained by pulsed laser ablation of metals in a liquid, and oxide bronzes KxTiO2 and NaxTiO2 are formed in the processes of self-propagating high-temperature synthesis and mechanical activation. An improvement in the efficiency of the diagnostic method by introducing antireflection additives and absorbing nanoparticles due to a decrease in the irradiation intensity and an increase in the photothermal effect is shown. OCT elastography data indicate the dependence of tissue deformation on the preliminary history of tissue exposure.

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35

Heller, Martina, Veronika Schon, Benedict Ott, and Peter Felfer. "Laser Ablation Sample Preparation for Grain Boundary Analysis of H in Atom Probe Tomography." Microscopy and Microanalysis 28, S1 (July 22, 2022): 694–96. http://dx.doi.org/10.1017/s1431927622003257.

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36

Kang, Jiqiang, Rui Zhu, Jianan Li, Haiping Liu, Xiuquan Ma, Ling Tao, and Yunxu Sun. "Optical coherence tomography-surveilled laser ablation using multifunctional catheter and 355-nm optical pulses." Optics Communications 501 (December 2021): 127364. http://dx.doi.org/10.1016/j.optcom.2021.127364.

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37

Zhenlin Zhan, 詹振林, 张先增 Xianzeng Zhang, 叶青 Qing Ye, and 谢树森 Shusen Xie. "Measurement of crater geometries after laser ablation of bone tissue with optical coherence tomography." Chinese Optics Letters 6, no. 12 (2008): 896–98. http://dx.doi.org/10.3788/col20080612.0896.

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38

Ohmi, Masato, Makoto Ohnishi, Daisuke Takada, and Masamitsu Haruna. "Dynamic analysis of laser ablation of biological tissue using real-time optical coherence tomography." Measurement Science and Technology 21, no. 9 (July 28, 2010): 094030. http://dx.doi.org/10.1088/0957-0233/21/9/094030.

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39

Galmed, A. H., A. du Plessis, S. G. le Roux, E. Hartnick, H. Von Bergmann, and M. Maaza. "Three dimensional characterization of laser ablation craters using high resolution X-ray computed tomography." Spectrochimica Acta Part B: Atomic Spectroscopy 139 (January 2018): 75–82. http://dx.doi.org/10.1016/j.sab.2017.11.011.

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40

Christensen, Rikke Louise, Vinzent Kevin Ortner, Merete Haedersdal, and Uffe Høgh Olesen. "Optical Imaging Visualizes a Homogeneous and Horizontal Band-Like Biodistribution of Large- and Small-Size Hydrophilic Compounds Delivered by Ablative Fractional Laser." Pharmaceutics 14, no. 8 (July 23, 2022): 1537. http://dx.doi.org/10.3390/pharmaceutics14081537.

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The skin barrier generally limits the topical delivery of hydrophilic molecules. Ablative fractional laser (AFL) facilitates cutaneous drug uptake of smaller hydrophilic compounds in several studies. In this imaging-based study, we aim to investigate the cutaneous biodistribution of two different-sized hydrophilic compounds delivered by an ablative fractional CO2 laser at minimally invasive settings. Intact or CO2 AFL-pretreated (2.5 mJ/mb and 5% density) ex vivo porcine skin was topically applied with a large or small hydrophilic compound (fluorescence labeled antibody nivolumab (150,000 g/mol, n = 4) or ATTO 647N (746 g/mol, n = 3)). Samples were incubated for 20 h in a Franz cell setup, whereafter optical coherence tomography (OCT) was used to assess laser channel depth, and ex vivo confocal microscopy (EVCM) was used to assess epidermal thickness and cutaneous biodistribution of nivolumab and ATTO 647N. With an EVCM-assessed median epidermal thickness of 70.3 µm and OCT-assessed ablation depth of 31.9 µm, minimally invasive settings enabled shallow penetration into the mid-epidermis. The AFL-assisted uptake of the antibody nivolumab and the smaller compound ATTO 647N showed a similar homogenous and horizontal band-like biodistribution pattern that reached mid-dermis. No uptake of nivolumab or ATTO 647N was observed in intact skin. In conclusion, AFL-induced mid-epidermal laser channels facilitates the cutaneous delivery of two hydrophilic compounds that are distributed in a similar homogeneous and horizontal band-like pattern, irrespective of their molecular size.

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41

Nadarajah, Ruksan, Shabbir Tahir, Joachim Landers, David Koch, Anna S. Semisalova, Jonas Wiemeler, Ayman El-Zoka, et al. "Controlling the Oxidation of Magnetic and Electrically Conductive Solid-Solution Iron-Rhodium Nanoparticles Synthesized by Laser Ablation in Liquids." Nanomaterials 10, no. 12 (November 27, 2020): 2362. http://dx.doi.org/10.3390/nano10122362.

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This study focuses on the synthesis of FeRh nanoparticles via pulsed laser ablation in liquid and on controlling the oxidation of the synthesized nanoparticles. Formation of monomodal γ-FeRh nanoparticles was confirmed by transmission electron microscopy (TEM) and their composition confirmed by atom probe tomography (APT). For these particles, three major contributors to oxidation were analysed: (1) dissolved oxygen in the organic solvents, (2) the bound oxygen in the solvent and (3) oxygen in the atmosphere above the solvent. The decrease of oxidation for optimized ablation conditions was confirmed through energy-dispersive X-ray (EDX) and Mössbauer spectroscopy. Furthermore, the time dependence of oxidation was monitored for dried FeRh nanoparticles powders using ferromagnetic resonance spectroscopy (FMR). By magnetophoretic separation, B2-FeRh nanoparticles could be extracted from the solution and characteristic differences of nanostrand formation between γ-FeRh and B2-FeRh nanoparticles were observed.

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42

Boettcher, Adeline N. "Preclinical Model of Optical Coherence Tomography for High-Resolution Deep-Brain Imaging for Laser Ablation." Radiology: Imaging Cancer 2, no. 3 (May 1, 2020): e204016. http://dx.doi.org/10.1148/rycan.2020204016.

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43

Li, Zhuoyan, Jin H. Shen, John A. Kozub, Ratna Prasad, Pengcheng Lu, and Karen M. Joos. "Miniature forward-imaging B-scan optical coherence tomography probe to guide real-time laser ablation." Lasers in Surgery and Medicine 46, no. 3 (March 2014): 193–202. http://dx.doi.org/10.1002/lsm.22214.

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44

Francica, G., G. Iodice, M. Delle Cave, R. Sarrantonio, G. Lapiccirella, V. Molese, D. Smeraldo, F. Scarano, and F. De Marino. "Factors predicting complete necrosis rate after ultrasound-guided percutaneous laser thermoablation of small hepatocellular carcinoma tumors in cirrhotic patients: a multivariate analysis." Acta Radiologica 48, no. 5 (June 2007): 514–19. http://dx.doi.org/10.1080/02841850701199942.

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Purpose: To assess factors affecting the effectiveness of percutaneous laser ablation (PLA) under ultrasound (US) guidance in terms of complete ablation achievement. Material and Methods: The clinical records of 86 hepatocellular carcinoma (HCC) tumors (mean diameter 23.7 mm) in 60 cirrhotic patients (mean age 68.3 years; 36 males; 57 HCV+; 53 Child's class A, seven Child's class B) treated by means of PLA were reviewed. PLA was performed with a continuous-wave Nd:YAG laser by a single operator who positioned two to four 300-µm optic fibers advanced in 21-gauge needles into target lesions under US guidance. Triphasic computed tomography (CT) studies were used to verify treatment effectiveness 1 month after PLA completion. The association between characteristics of the lesion and outcome (complete or incomplete ablation) was evaluated by logistic regression, taking into account the following predictive factors: tumor size, pattern of growth (infiltrating or not) at imaging, location, first diagnosis of HCC (naïve tumors vs. non-naïve tumors), number of sessions (1/>1), total delivered energy, and years of treatment in 2001–2002 (first period) vs. 2003–2004 (second period). Results: Complete ablation was obtained in 62 nodules (72%). Statistically significant predictors of incomplete ablation after the first PLA course at both univariate and multivariate analysis included: infiltrating growth pattern (odds ratio (OR) 12.3, P<0.002), non-naïve tumors (OR 8.7, P<0.001), and first period of treatment (OR 10.3, P<0.002). Conclusion: The effectiveness of US-guided PLA for HCC tumors ⩽4 cm turned out to be negatively affected by both operator-related (the beginning of the operator's experience with the technique) and tumor-related factors (non-naïve, infiltrating HCC tumors).

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45

Wang, Zhao, Hsiang-Chieh Lee, Osman Ahsen, Kaicheng Liang, Marisa Figueiredo, Qin Huang, James Fujimoto, and Hiroshi Mashimo. "Computer-Aided Analysis of Gland-Like Subsurface Hyposcattering Structures in Barrett’s Esophagus Using Optical Coherence Tomography." Applied Sciences 8, no. 12 (November 28, 2018): 2420. http://dx.doi.org/10.3390/app8122420.

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(1) Background: Barrett’s esophagus (BE) is a complication of chronic gastroesophageal reflux disease and is a precursor to esophageal adenocarcinoma. The clinical implication of subsurface glandular structures of Barrett’s esophagus is not well understood. Optical coherence tomography (OCT), also known as volumetric laser endomicroscopy (VLE), can assess subsurface glandular structures, which appear as subsurface hyposcattering structures (SHSs). The aim of this study is to develop a computer-aided algorithm and apply it to investigate the characteristics of SHSs in BE using clinical VLE data; (2) Methods: SHSs were identified with an initial detection followed by machine learning. Comprehensive SHS characteristics including the number, volume, depth, size and shape were quantified. Clinical VLE datasets collected from 35 patients with a history of dysplasia undergoing BE surveillance were analyzed to study the general SHS distribution and characteristics in BE. A subset of radiofrequency ablation (RFA) patient data were further analyzed to investigate the pre-RFA SHS characteristics and post-RFA treatment response; (3) Results: SHSs in the BE region were significantly shallower, more vertical, less eccentric, and more regular, as compared with squamous SHSs. SHSs in the BE region which became neosquamous epithelium after RFA were shallower than those in the regions that remained BE. Pre-ablation squamous SHSs with higher eccentricity correlated strongly with larger reduction of post-ablation BE length for less elderly patients; (4) Conclusions: The computer algorithm is potentially a valuable tool for studying the roles of SHSs in BE.

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46

Stephenson, J. D. "White Synchrotron Radiation Tomography of fs-Excimer Laser Ablation/Bulk Damage in a (100) Si Wafer." physica status solidi (a) 165, no. 1 (January 1998): R1—R2. http://dx.doi.org/10.1002/(sici)1521-396x(199801)165:13.0.co;2-v.

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47

Fan, Yingwei, Boyu Zhang, Wei Chang, Xinran Zhang, and Hongen Liao. "A novel integration of spectral-domain optical-coherence-tomography and laser-ablation system for precision treatment." International Journal of Computer Assisted Radiology and Surgery 13, no. 3 (September 9, 2017): 411–23. http://dx.doi.org/10.1007/s11548-017-1664-8.

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48

Ureel, Matthias, Marcello Augello, Daniel Holzinger, Tobias Wilken, Britt-Isabelle Berg, Hans-Florian Zeilhofer, Gabriele Millesi, Philipp Juergens, and Andreas A. Mueller. "Cold Ablation Robot-Guided Laser Osteotome (CARLO®): From Bench to Bedside." Journal of Clinical Medicine 10, no. 3 (January 24, 2021): 450. http://dx.doi.org/10.3390/jcm10030450.

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Background: In order to overcome the geometrical and physical limitations of conventional rotating and piezosurgery instruments used to perform bone osteotomies, as well as the difficulties in translating digital planning to the operating room, a stand-alone robot-guided laser system has been developed by Advanced Osteotomy Tools, a Swiss start-up company. We present our experiences of the first-in-man use of the Cold Ablation Robot-guided Laser Osteotome (CARLO®). Methods: The CARLO® device employs a stand-alone 2.94-µm erbium-doped yttrium aluminum garnet (Er:YAG) laser mounted on a robotic arm. A 19-year-old patient provided informed consent to undergo bimaxillary orthognathic surgery. A linear Le Fort I midface osteotomy was digitally planned and transferred to the CARLO® device. The linear part of the Le Fort I osteotomy was performed autonomously by the CARLO® device under direct visual control. All pre-, intra-, and postoperative technical difficulties and safety issues were documented. Accuracy was analyzed by superimposing pre- and postoperative computed tomography images. Results: The CARLO® device performed the linear osteotomy without any technical or safety issues. There was a maximum difference of 0.8 mm between the planned and performed osteotomies, with a root-mean-square error of 1.0 mm. The patient showed normal postoperative healing with no complications. Conclusion: The newly developed stand-alone CARLO® device could be a useful alternative to conventional burs, drills, and piezosurgery instruments for performing osteotomies. However, the technical workflow concerning the positioning and fixation of the target marker and the implementation of active depth control still need to be improved. Further research to assess safety and accuracy is also necessary, especially at osteotomy sites where direct visual control is not possible. Finally, cost-effectiveness analysis comparing the use of the CARLO® device with gold-standard surgery protocols will help to define the role of the CARLO® device in the surgical landscape.

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49

Moskvicheva, L. I. "High-intensity focused ultrasonic ablation of breast cancer." Research'n Practical Medicine Journal 5, no. 3 (September 9, 2018): 67–76. http://dx.doi.org/10.17709/2409-2231-2018-5-3-6.

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Breast cancer is the most frequent and socially signiﬁ cant malignant tumor disease of the female popula on of the Russian Federa on. At present, for the treatment of this pathology, the methods of the organ-preserving surgical manual allowing to achieve the maximum cosme c eﬀ ect along with the observance of the principles of cancer safety are ge ng more and more developed,. In recent decades, researchers from diﬀ erent countries demonstrate the feasibility and technical safety of various mini-invasive methods of thermal abla on of early stages of breast cancer, characterized by rela ve simplicity of implementa on, excellent cosme c results, short-term rehabilita on of pa ents. These include hyperthermic techniques (radiofrequency, microwave, laser abla on) and hypothermic method (cryoabla on). Each technique has unique characteris cs of impact on the tumor and is performed under the control of ultrasound, computer tomography or magne c resonance imaging. The technical success of these abla on techniques is achieved in 93–98% of cases. Complete tumor necrosis a er radiofrequency abla on is observed in 76–100% of pa ents with breast cancer, laser abla on – in 13–76%, microwave abla on – in 0–8%, cryoabla on – in 36–83%. The frequency of development of speciﬁ c complica ons of local thermal destruc on is 4–13%. To date, there is only one method of noninvasive extracorporeal thermal abla on of tumors of diﬀ erent localiza on – high-intensity focused ultrasound therapy, the eﬀ ec veness and safety of which as a method of local destruc on of benign and malignant tumors of the breast demonstrated by many authors. Like all methods of thermal abla on, high-intensity focused ultrasound therapy has its limita ons, complica ons and disadvantages. This ar cle presents a literary review that highlights the possibili es of this method of local destruc on in pa ents with malignant tumors of the breast.

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50

Jimie, Joachim, Abigail Kwok, Fadi Housami, Mahmoud Elfar, and Baher Hussein. "Diode Laser for the Management of Upper Tract Urothelial Cancer (UTUC) – Case Series." Journal of Endoluminal Endourology 5, no. 3 (November 29, 2022): e14-e21. http://dx.doi.org/10.22374/jeleu.v5i3.147.

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Background and Objective: Upper tract urothelial carcinoma (UTUC) is uncommon; however, at the time of diagnosis, they are usually more invasive than bladder urothelial carcinomas. Although nephroureterectomy (NU) has been the gold-standard treatment, guidelines have been set for kidney-sparing treatment in selected groups of patients. While these guidelines are aimed towards patients fit for salvage radical treatment, little has been published on managing the symptomatic patient not fit for NU. Various modalities of endoscopic ablation in managing UTUC have been described in the literature, but there is currently no reported use of the diode laser. Therefore, we aim to assess its efficacy and safety profile in the ablation of UTUC in patients unfit for major abdominal surgery in radical nephroureterectomy regardless of the tumour grade and size. Patients and method: A single centre retrospective review of patients who underwent Diode Laser treatment for UTUC over 4 years was done. Follow up through 6 monthly ureteroscopy alternating with computed tomography (CT) urogram was done to assess the need for further treatment. Results: 30 patients were identified, with mean age 76 years (64-88) and variable tumour locations, including lower and mid ureter and renal pelvis, upper and lower calyces. 76.7% were ASA 3 and 20% ASA 4. The mean tumour size was 3.8 cm (2-7 cm). The mean number of sessions was 2.1 (1-6). 63.3% of the tumours were grade 2, while 30% were grade 3. A case of metastatic renal-cell carcinoma was diagnosed as a 4 cm filling defect in the kidney where the diode laser was used for resection biopsy and ablation. 16.7% experienced Clavien-Dindo grades 1-2 complications. A total of 6.7% of patients were converted to an inpatient stay. None of the patients needed blood transfusion nor did any develop a ureteric stricture on subsequent ureteroscopies. 48.3% of patients experienced clinical recurrences of which 57.1% were at a different site. Two of the patients developed metastatic disease. One patient died 3 years after initial treatment with disease progression. Conclusion: The management of UTUC with diode laser is a safe and efficacious conservative treatment for disease and symptom control in patients unfit for radical treatment.

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