Prospects of Endovenous Laser Ablation (EVLA) Standardization-Mid-Term Results of a Four-Zone Dosimetry Guiding Tool for 1940 nm Laser.

BACKGROUND: Heterogeneity regarding dosimetry and reporting of endovenous laser ablation (EVLA) mandates the development of a standardized protocol. This study presents the mid-term results of EVLA with 1940 nm-laser and radial-fibre, supported by a four-zone dosimetry tool. MATERIALS AND METHODS: Four anatomical dosimetry zones for great saphenous veins (GSV) and two for small saphenous veins (SSV) were defined with set power levels. Zone-1G (4 W) extended from the inguinal ligament to the apex of femoral triangle, Zone-2G (4 W) from the apex of femoral triangle to the upper border of patella. Zone-3G (3 W) from the patella to the tibial tuberosity. Zone-4G (2 W) extended from the tibial tuberosity to the ankle. Zone-1S from the sapheno-popliteal junction to the tibial tuberosity. Zone-2S from the tibial tuberosity to the ankle. Power was increased by 1 W for veins >10 mm and decreased by 1 W when fibre sticking was encountered. Pullback-velocity was max. 1 mm/s. RESULTS: A total of 152 consecutive patients (185 procedures) were recruited. Mean follow-up time was 11.9 months. Mean linear endovenous energy density for GSV was Zone-1G:42 J/cm, Zone-2G:33 J/cm, Zone-3G:27 J/cm, Zone-4G:22 J/cm, Zone-1S:34 J/cm, Zone-2S:27 J/cm. Occlusion rates were 98.9% (1-month) and 93.7% (12-months). Complications at 1 M were low, namely laser-induced paraesthesia (LIP) 2.2% and endovenous heat-induced thrombosis (EHIT) 1.6%. Persistent LIP (12 M) was observed in 0.5%. CONCLUSION: The proposed four-zone guiding tool is a step towards standardizing dosimetry and documentation for EVLA with 1940 nm. This strategy shows good mid-term results with minimal complications. Long-term follow-up and application in further centres are necessary to prove its reproducibility. Such a guiding tool could improve the ability to analyse, compare and review different EVLA wavelengths and fibre types.

Acute Abdominal Pain as a Result of an Isolated Left Ovarian Vein Thrombosis.

Ovarian vein thrombosis (OVT) is a rare thromboembolic condition. It involves the right ovarian vein in 70-80% of cases. The risk factors for the development of OVT are pregnancy or puerperium, hormone therapy with estrogen, recent surgery or hospitalization, malignancy, pelvic inflammatory diseases, thrombophilia and idiopathic OVT. We present a rare case of left OVT in a young, non-pregnant woman in her 30 s. A high degree of suspicion is necessitated in patients with the triad of young-middle-aged female, pain abdomen in lower quadrant and hematuria to diagnose OVT. Contrast enhanced computer tomography (CT-venography) is the diagnostic modality of choice. The patient was initially treated with low molecular weight heparin and then switched to direct oral anticoagulants. At 6-monthsfollow-up the patient was free from any symptoms.

Endovenous laser ablation using laser systems emitting at wavelengths > 1900 nm: a systematic review.

The aim of this systematic review was to summarize the currently available literature reporting clinical application of endovenous laser ablation (EVLA) by means of laser systems emitting at wavelengths > 1900 nm, pertaining dosimetry, intraoperative parameters, postoperative outcomes, and efficacy based on occlusion rates, recanalization, and postoperative complications. A literature search was conducted in PubMed, Cochrane Library, Embase, OVID, and Web of Science for publications since the year 2000 until December 2021. Case series, prospective trials, retrospective studies, and randomized controlled trials describing the application of a 1920/1940-nm wavelength laser for EVLA in humans with a minimum of one postoperative follow-up visit were included in the study. Four case series and one randomized controlled trial with a total of 509 EVLA procedures (396 great saphenous veins and 113 small saphenous veins) were identified, meeting the inclusion criteria. The studies were heterogenous in their documentation, EVLA, and duplex ultrasound protocol and result reporting. Overall, the applied average cumulative LEED values ranged from 17.8 to 53 J/cm. Complications observed were pigmentation (0-9.75%), paresthesia (2.5-7.3%), thrombophlebitis (0-5%), EHIT Class 2 (2.26-2.4%), and EHIT Class 1 (1.2-2.4%). Four cases of recanalizations were observed in one study cohort within the first month after treatment. Follow-up at 12 months was available for 3 studies (procedures n = 218) with recanalizations in 8 limbs. Follow-up at 24-36 months was available for 2 studies (procedures n = 126) showing recanalizations in 5 limbs. Recanalizations were asymptomatic and incidental findings on follow-up duplex ultrasound. Pooled occlusion rates were 99.2% at 1 M, 96.3% at 12 M, and 96% at 24 M. Overall, patients undergoing EVLA with long wavelength laser systems > 1900 nm show high occlusion rates, significant improvement in VCSS, low postoperative complication rate, low pain levels, low analgesic requirement, and early convalescence. Apart from persistent paresthesia, all the complications regressed spontaneously within 6 months. EVLA by means of 1920/1940 nm shows promising clinical results with high efficacy and low complication rates. Heterogeneity still exists regarding ideal protocol for duplex ultrasound examination and documentation of anatomical parameters (e.g., vein diameter, ideal stump length and status of accessory veins) and light dosimetry for EVLA.

Safety and efficacy of endovenous laser ablation (EVLA) using 1940 nm and radial emitting fiber: 3-year results of a prospective, non-randomized study and comparison with 1470 nm.

OBJECTIVES: To evaluate the safety, efficacy and ≥36 months outcomes of endovenous laser ablation (EVLA) by means of 1940 nm laser with radial fiber for the treatment of truncal vein insufficiency and compare the results to a historical cohort, obtained via reviewing the literature. METHODS: This prospective, non-randomized, single-center clinical study included 139 consecutive patients with 177 incompetent great saphenous (GSV, n = 135) and short saphenous veins (SSV, n = 42). The maximum laser power (Pmax. 10 W) and pullback velocity were adjusted individually (Vmax = 1 mm/s). The laser fiber was placed at the junction to the deep vein under duplex monitoring. Simultaneous phlebectomies were performed on all the patients. Regular follow up with clinical and duplex ultrasound examination (DUS) were carried out postoperatively at 1 month (1 M), 6 months (6 M), 12 months (12 M), 24 months (24 M), 36 months, and after that (≥36 M). The results were compared with three cohorts (total 616 EVLA procedures with 1470 nm laser and radial fiber) from literature (criteria: >100 procedures, follow-up of ≥2 years). RESULTS: The follow-up rate was 100%, 91%, 73%, 48%, and 23% of the truncal veins at 1, 6, 12, 24, and ≥36 M, respectively. In comparison to the literature using 1470, a lower average linear endovenous energy density (LEED) (53 vs. 77-82 J/cm) resulted in 100% (6 M) and 96.5% (24 M) occlusion rates, reduced local ecchymosis (2.2% vs. 3.2%-18.7%) and reduced average postoperative pain levels (1.3 vs. 2.18). Regarding adverse events, induration (1.1% vs. 1.8%), skin burns (0% vs. 0.45%), endovenous heat-induced thrombus propagation (EHIT) in the deep veins (2.3% vs. 1.8%) and laser-induced persistent paresthesia (2.2% vs. 0.5%-2.9%) were comparable. Recanalizations observed in this study (GSV 0, SSV 3) were asymptomatic and required no treatment. At ≥36 M reflux in the accessory veins was observed in 5% versus 10.5% of patients. Reintervention was required in none (0% vs. 21%). At >36 M, short average stump lengths of 1 cm (GSV) and 0.3 cm (SSV) were observed. CONCLUSION: EVLA with 1940 nm laser with radial emitting fiber is as safe and effective as 1470 nm laser for the treatment of truncal vein insufficiency. Lower postoperative pain, low analgesic requirements, short convalescence add to patients' comfort. EVLA with 1940 nm laser-guided by intraoperative DUS permits reproducible placement of the radial fiber at the saphenofemoral and saphenopopliteal junction, enabling further studies to assess the effect of shorter stump length on patterns and frequency of recurrence without increased risk of EHIT.