Endovenous laser treatment to promote venous occlusion

The origin of loud claps during endovenous laser treatments

Optoacoustic and ultrasound methods have shown that the loud "claps" perceived by patients and medical staff during endovenous laser ablation (EVLA) are caused by volumetric blood boiling when large vapor-gas bubbles appear and collapse under the action of laser radiation, which is well absorbed in water. Acoustic effects when using lasers in the near infrared range (1.94, 1.47, and 0.97 μm) were studied in an experiment with non-deaerated water, as well as in EVLA. The nature of these acoustic signals was investigated using high-speed video recording. It turned out that the amplitude of the emerging acoustic pulses in the case of surface boiling, which prevails when using lasers with a wavelength of 0.97 μm, is two orders of magnitude smaller than in the case of volumetric boiling (1.94 and 1.47 μm). The reasons for the decrease in sound effects in this case are associated with numerous microbubbles at the tip of the laser fiber. The results obtained may be useful for further understanding of the mechanisms of EVLA.

Foaming of blood in endovenous laser treatment

This work is dedicated to a challenging issue of modern phlebology-establishment of a physical mechanism of the endovenous laser treatment (EVLT) against great saphenous vein incompetence (protuberant varicosities). Using optical and acoustical methods, we have studied the laser-induced formation of microbubbles in an aqueous solution of surface-active substances, serum, and blood directly in patients while conducting EVLT of the great saphenous vein in a clinical setting. We have used lasers with wavelengths 0.97 and 1.47 μm. Their radiation was transmitted through a quartz-quartz polymer fiber 600 μm in diameter. It has been found that in all cases, the laser beam with moderate power (1-10 W) supplied through an optical fiber leads to the formation of micro-bubbled foam. It has been shown that laser exposure during EVLT induces blood boiling, which results in heating of the venous walls (thermal destruction of the intima) and provides effective foam occlusion of the blood vessels (hemostasis). Necessary and sufficient conditions for a successful EVLT are associated with the thermal destruction of intima and laser-induced foam hemostasis.

Endovenous laser ablation of the great saphenous vein – Varying energy may not affect outcome

Objectives

To determine great saphenous vein occlusion rate after endovenous laser ablation using the 1470-nm bare-fiber diode laser to supply either 7 W or 15 W and evaluate procedure-related complications.

Method

Patients with varicose veins of the lower extremities (CEAP class C2–C6) were randomly assigned to undergo either 7-W (18 patients, 30 limbs) or 15-W (18 patients, 30 limbs) endovenous laser ablation. Duplex ultrasound follow-up was at 3–5 days, 1, 6, and 12 months postoperatively.

Results

Occlusion rate was 100% in both groups at 3–5 days and 1 month and 86.7% in 7-W and 100% in 15-W patients at both 6 and 12 months, with no difference between groups ( p > 0.05). Four (13.3%) 15-W and 3 (10%) 7-W patients had paresthesia at 3–5 days, with no difference between groups ( p > 0.05).

Conclusions

These preliminary data suggest that both techniques are similarly effective in the treatment of varicose great saphenous veins.

Comparison of 1470 nm Laser and Radial 2ring Fiber with 980 nm Laser and Bare-Tip Fiber in Endovenous Laser Ablation of Saphenous Varicose Veins: A Multicenter, Prospective, Randomized, Non-Blind Study

OBJECTIVE

The aim of this study is to compare the clinical efficacy and safety of two laser wavelengths and fiber types in endovenous laser ablation (EVLA) of saphenous varicose veins of the lower limb.

DESIGN

Multi-center prospective randomized non-blind clinical trial.

PATIENTS AND METHODS

From January 2007 to December 2011, 113 patients (113 limbs) with primary varicose veins were randomized into two groups. They were treated with radial 2ring fiber and 1470 nm laser in Group I (57 limbs) and bare-tip fiber and 980 nm laser in Group E (56 limbs) in order to ablate the saphenous vein. Vein occlusion rates at 12 weeks and pain in treated region were recorded as primary endpoint. Visual analogue scale (VAS) for assessment of pain, rates of bruising, complications and equipment failure were recorded as secondary endpoint of safety.

RESULTS

Occlusion rates at 12 weeks were 100% in both groups. Rates of pain (0% vs. 25.0%) and bruising (7.0% vs. 57.1%) were significantly lower in Group I (p <0.0001). VAS of pain was significantly lower on postoperative day 1, day 5 and 2nd week in Group I.

CONCLUSION

Treatment of saphenous varicose veins by EVLA using a 1470 nm laser and a radial 2ring fiber resulted in comparable occlusion rates at 12 weeks and less postoperative pain and bruising than EVLA with a 980 nm laser and a bare-tip fiber. (This article is a translation of Jpn J Vasc Surg 2014; 23: 964-971.).

Endovenous laser treatment (EVLT) for the saphenous reflux and varicose veins: a follow-up study

PURPOSE

The aim of this study is to report our experience about endovenous laser treatment (EVLT) for lower extremity varices in our centre which was followed by ultrasonography during the 6-month period.

METHODS

During a 1-year period, 46 patients who were treated by EVLT with the 940-nm diode laser for venous insufficiency enrolled in the study. The diagnosis of greater saphenous vein (GSV) incompetence with reflux was made by clinical evaluation and duplex Doppler examinations. Clinical outcomes, complications and duplex ultrasound of the GSV were assessed within 1 week, 1 month, 3 months and 6 months, after the endovascular laser treatment.

RESULTS

The mean age of our patients was 44 ± 11 years (24-70), and among them, 23 (50%) were male. Improvement in visible varicosity was seen in 39 (84.8%) patients after 6 months (P value = 0.011). The baseline mean diameter of GSV was 4.9 ± 1.6 mm and it dropped to 3.5 ± 1.3 after 6 months (P < 0.0001). After 6 months, 95.7% of our patients were satisfied and recommended this procedure to others.

CONCLUSIONS

Endovascular laser ablation seems to be a safe and effective method for the treatment of lower limb varices.

Combined endovascular laser plus ambulatory phlebectomy for the treatment of superficial venous incompetence: A 4‐year perspective

BACKGROUND

Combination endovascular laser obliteration of the greater saphenous vein in conjunction with ambulatory phlebectomy has become the treatment of choice for superficial venous incompetence.

OBJECTIVES

The present study examines the treatment of saphenofemoral junction (SFJ) incompetence with simultaneous treatment of associated truncal varicosities by ambulatory phlebectomy.

METHODS

Four-year follow-up data for recurrence rate and complication profile was ascertained for 90 patients (mean age 40 years) with SFJ reflux associated with greater saphenous vein (GSV) incompetence (4-12 mm; mean 7.8 mm) and enlargement of branch varicosities as documented by Duplex ultrasound, which were treated with a combined approach of endovascular laser obliteration of the GSV (810 nm, Diomed S30) followed by hook avulsion (ambulatory phlebectomy) of the remaining truncal varicosities. Follow-up by Duplex ultrasound to ensure closure was carried out at week 1 and months 1, 3, 6, 12, 24, 36 and 48.

RESULTS

A total recurrence rate (r = 94 limbs) of 4.3 was found in the patient cohort. All recurrences occurred within 12 months, with the majority documented at month 6.

CONCLUSIONS

Combination endovascular laser treatment (EVLT) with ambulatory phlebectomy is an effective treatment modality for superficial venous incompetence in the outpatient ambulatory setting. Low recurrence rates are noted with this approach. In the present patient series, all recurrences were noted within 12 months of the aforementioned procedure. These results are comparable with other endovenous and radiofrequency technologies.

Endovenous laser treatment for uncomplicated varicose veins

Objective

Endovenous laser ablation (EVLA) of incompetent truncal veins has been proposed as a minimally invasive alternative to conventional surgery for varicose veins. Various strategies have been proposed for successful treatment and this study reviews the evidence for these.

Method

A Medline and ‘controlled trials online database’ search was performed to identify original articles and randomized controlled trials (RCTs) reporting outcomes for EVLA. Information on patient selection, equipment, technique and outcomes were recorded.

Results

Ninety-eight original studies, including five RCTs, were identified. RCT data indicate short-term outcomes (abolition of reflux, improvement in quality of life [QOL], patient satisfaction) were equivalent to those for surgery. Long-term follow-up is not available. A further RCT showed superior outcomes for ablation commencing at the lowest point of superficial venous reflux rather than at an arbitrary point (fewer residual varicosities, greater improvement in QOL). Non-randomized series suggest that laser energy of >60 J/cm results in reliable truncal vein occlusion and that longer wavelength lasers may be associated with less post-treatment discomfort.

Conclusion

In the short-term EVLA is a safe and effective treatment for patients with varicose veins. Long-term follow-up is still required.

Endovenous Laser Treatment of Saphenous Vein Reflux: How Much Energy Do We Need to Prevent Recanalizations?

The aim of this study was to report the results of high-energy endovenous laser treatment to measure the relationship between the fluence and the outcome in terms of recanalization. In 97 patients, 129 great saphenous veins were treated with endovenous laser treatment, using a 980-nm diode laser. Follow-up visits were done at 3 days, 1 month, and 6 months. The best results were noted 1 month postoperative, but at 6 months, control late recanalizations occured decreasing occlusion rate to 90.6%. Patients were divided into 2 groups according to the outcome (occlusion or recanalization) at 6 months, and statistical analysis was done. The authors found 52 J/cm2 mean fluence in the occlusion group and 43.7 J/cm2 in the nonocclusion group. This was a statistical significant difference ( P < .01). The occlusion rate on long term is fluence dependent. But recanalizations might occur even in these higher fluence treatment groups. A fluence of 52J/cm2 is advised.

Laser therapy of vascular lesions

Since the first construction of a laser by Maiman in 1960 and the first clinical application of a laser in the therapy of skin lesions by Leon Goldman, laser therapy has become an important therapeutic modality in dermatology. Various lasers can be used for the treatment of different vascular and non-vascular lesions. According to our results, vascular lesions constitute the most important indication for laser therapy in dermatology.

Métodos físicos utilizados para oclusão de varizes dos membros inferiores

A terapia das varizes dos membros inferiores tem sido realizada classicamente por cirurgia e escleroterapia, sendo a escolha basicamente dependente do seu calibre. Entretanto, a associação de técnicas costuma ser uma necessidade para a obtenção de bons resultados. Os meios físicos surgiram no final da década de 50 e continuaram a progredir com grande diversidade quanto à natureza, princípio físico e efeitos. A complexidade tecnológica é bastante variável. Eletrocoagulação, laser, luz intensa pulsada, crioesclerose endovascular, ultra-som e microondas são meios físicos potencialmente viáveis para esta condição. Entretanto, com algumas exceções, pouco tem sido descrito fora dos centros de pesquisa, e a participação como opção terapêutica ainda necessita de uma melhor definição do papel. O artigo tem como objetivo descrever os métodos físicos empregados ou em estudo para a terapia de varizes.

Intravascular 1320-nm Laser Closure of the Great Saphenous Vein: A 6- to 12-Month Follow-up Study

OBJECTIVE

The objective was to determine the safety and efficacy of an intravascular laser with a novel wavelength to close the great saphenous vein.

METHODS

Twenty-four cases of an incompetent great saphenous vein (0.5-1.2 cm in diameter) associated with distal varicose veins were treated with a 1320-nm intravascular laser at 5 W with an automatic pullback mechanism at 1 mm/s. Patients were evaluated with duplex ultrasound to determine efficacy of treatment at various time periods to at least 6 months after the procedure.

RESULTS

All patients demonstrated complete closure of the incompetent great saphenous vein. In most cases, the treated great saphenous vein was not identifiable 6 months postoperatively. There was no recurrence of any varicose veins. All preoperative symptoms resolved after treatment, and no complications were noted. All patients were very pleased with the outcome of the procedure.

CONCLUSIONS

At 6 months or greater follow-up, a 5-W, 1320-nm intravascular laser with 1 mm/s automatic pullback, delivered through a diffusion-tip fiber, is safe and effective in treating an incompetent great saphenous vein up to 1.2 cm in diameter.