Photoacoustic-guided endovenous laser ablation: Characterization and in vivo canine study.
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ABSTRACT:
SUBMITTER: Yan Y
PROVIDER: S-EPMC8416949 | biostudies-literature | 2021 Dec
REPOSITORIES: biostudies-literature
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Photoacoustic-guided endovenous laser ablation: Characterization and <i>in vivo</i> canine study.
Yan Yan Y John Samuel S Shaik Tanyeem T Patel Bijal B Lam Mai T MT Kabbani Loay L Mehrmohammadi Mohammad M
Photoacoustics 20210830
Endovenous laser ablation (EVLA) is a minimally invasive surgical procedure, often guided by ultrasound (US) imaging, for treating venous insufficiencies. US imaging limitations in accurately visualizing the catheter and the lack of a temperature monitoring system can lead to sub-optimal outcomes. An integrated photoacoustic (PA)-guided EVLA system has been previously developed and reported to overcome the shortcomings of US-guided procedure. In this study, we further characterized the system an ...[more]
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Project description:Background and aimsLocal 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).MethodsEUS-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.ResultsEUS-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).ConclusionsIn 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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Project description:BackgroundRecurrences after varicose vein treatment occur frequently and represent a significant health and economic problem. In contrast to primary treatments of superficial truncal venous insufficiency, their management is often more difficult. Here we assessed the technical feasibility and early results of endovenous laser ablation (EVLA) for recurrences with stumps or subfascial meandering varices after small saphenous vein (SSV) surgery.MethodsThis single-center retrospective study included 45 consecutive EVLA procedures from July 2019 to December 2021 in 40 patients (19 male, 21 female, mean age 62.8 ± 12.7 years). Patients had clinically relevant recurrent varicose veins after SSV surgery, with clinical, etiologic, anatomic and pathophysiologic (CEAP) classification stage of C2S or higher. We categorized the recurrences morphologically according to duplex sonographic criteria. Ablations were done with a 1470 nanometers laser and dual ring radial fibers and aimed at thermal closure as proximal as possible to the upper inflow. Analyses were performed by descriptive statistics and the Kaplan-Meier method. The primary outcome analyzed was the technical success, defined by thermal occlusion not requiring re-intervention during the observation period. The secondary outcome was the occurrence of postoperative complications.ResultsA complex morphology with residual stumps or tortuous venous connections to the popliteal vein was present in 35 cases (77.8%). Immediate technical success at the first postoperative visit after a median of 11 days (interquartile range 8-13 days) was 97.8%. During the follow-up period (median 77 days, interquartile range 13-256 days), 6 limbs (13.3%) required redo EVLA due to symptomatic persistent or newly presenting reflux. The median freedom from re-recurrence was 791 days. Otherwise, no medical or surgical complications requiring specific treatment were observed, particularly no endothermal heat-induced thrombosis (EHIT) or other thrombotic complications, and no nerve damage.ConclusionAccording to our pilot data, EVLA is technically feasible for complex popliteal variceal recurrence, although the success rate appears substantially lower than for primary treatment of truncal venous insufficiency.
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Project description:BackgroundRecurrent varicosities after endovascular laser ablation (EVLA) of the great saphenous vein (GSV) are frequently due to varicose transformed, initially unsealed major ascending tributaries of the saphenofemoral junction (SFJ). Preventive ablation of these veins, especially the anterior accessory saphenous vein, is discussed as an option, along with flush occlusion of the GSV. However, few related data exist to date.MethodsA consecutive case series of 278 EVLA procedures of the GSV for primary varicosis in 213 patients between May and December 2019 was retrospectively reviewed. The ablations were performed with a 1470 nm dual-ring radial laser and always included flush occlusion of the GSV, and concomitant ablation of its highest ascending tributaries by additional cannulation and ablation when this seemed anatomically appropriate. The initial technical success, comprising occlusion of the GSV and its major tributaries, was set as the primary endpoint. Possible determinants were explored using downstream multiple logistic regression analysis.ResultsThe early technical success was 92.8%, with the GSV occluded in 99.6% and the highest ascending SFJ tributary, if present, in 92.4%. Additional ablations of ascending tributaries were performed in 171 cases (61.5%), the latter being associated with success (OR 10.39; 95% CI [3.420-36.15]; p < 0.0001). Presence of anterior as opposed to posterior accessory saphenous vein was another positive predictor (OR 3.959; 95% CI [1.142-13,73]; p = 0.027), while a confluence of the tributary in the immediate proximity to the SFJ had a negative impact (OR 0.2253; 95% CI [0.05456-0.7681]; p = 0.0253). An endothermal heat-induced thrombosis (EHIT) ≥ grade 2 was observed in three cases (1.1%).ConclusionsA co-treatment of the tributaries is feasible and could improve the technical success of EVLA if a prophylactic closure of these veins is desired, especially if their distance to the SFJ is short. Its effect on the recurrence rate needs further research.
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