Endovenous laser ablation therapy in children: applications and outcomes

We obtained institutional research ethics board approval for this two-center retrospective observational study. We collected data from two large pediatric institutions with both pediatric vascular anomaly services and well-established pediatric interventional radiology programs (The Hospital for Sick Children, Toronto, Canada, and Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK). We included all consecutive patients 0–18 years of age who underwent endovenous laser ablation between January 2007 and July 2014. There were no exclusion criteria. We identified these patients by searching each institution’s interventional radiology database for the procedure “endovenous laser ablation.” Data sources included the institutional picture archiving and communication systems, prospectively collected dedicated interventional radiology databases and paper or electronic patient charts.

Demographics recorded included age, weight at the time of endovenous laser ablation and gender. We also recorded pre-procedural diagnosis, symptoms and imaging findings. Procedural data included aim of treatment, number and nature of veins treated, endovenous laser ablation technique, additional endovascular procedures performed at the same time as endovenous laser ablation and recovery time. Post-procedural data collected included postoperative imaging, complications, outcome and length of follow-up. Complications were graded according the Society of Interventional Radiology classification of complications [5].

Informed consent for endovenous laser ablation with or without additional endovascular procedures was obtained prior to all procedures. The procedures were performed under sterile conditions in an angiography suite. Procedures were performed under general anesthesia with continuous monitoring of vital functions. The target vein was accessed percutaneously by using a micropuncture technique with US guidance. A 4-French laser sheath was advanced over a 0.035-in. wire to the intended start point of ablation. The wire was exchanged for the laser fiber, ensuring the laser fiber tip remained covered by the sheath. Tumescent fluid was injected around the entire length of the target vein. The tumescent fluid used was 0.9% sodium chloride solution in 37 procedures, and lactated Ringer solution in 4 procedures. Lidocaine was added to the fluid in six procedures early in the series; no local anesthetic was used for the other procedures. Because of target vein length, four veins required two access sites and one vein required three access sites. Where multiple access sites were used, access was gained at all sites before administration of tumescent fluid. An 810-nm Diode laser with 600-μm bare-tip fiber was used. The endovenous laser ablation systems were either Vari-Lase (Aquilant Interventional, Hampshire, UK) or Diomed EVLT (AngioDynamics, New York, NY). The power used was 10–14 watts in continuous mode with a pullback rate of 1–2 mm/s. Immediately following the procedure, either 20–30 mmHg or 30–40 mmHg compression garments were applied and worn for 6–12 weeks. Eight patients received prophylactic peri-procedural anticoagulation; five of these patients were known to be prothrombotic. Endovenous laser ablation was preceded by venography or venous outflow embolization and followed by sclerotherapy in select cases.

Eighteen lower-limb veins were ablated in 15 patients with venous malformations (right in 8 patients, left in 7 patients) (Table 1). In 12 patients, the aim of endovenous laser ablation was to close the venous outflow from the lesion to enable safe injection of sclerosant into the venous malformation (Fig. 1). In two patients, endovenous laser ablation was performed in the greater saphenous vein to manage venous thrombosis — in one to prevent recurrence of distal massive thrombus, which had formed at a previous sclerotherapy treatment, and in the other to prevent thrombus propagation and pain after thrombus developed following sclerotherapy. In one patient, endovenous laser ablation of the short saphenous vein was performed to reduce symptoms of recurrent thrombophlebitis. One vein required three separate endovenous laser ablation procedures and one vein required two procedures to achieve closure. Six patients had additional procedures to close the ablated vein at the time of endovenous laser ablation: four had sclerotherapy post-ablation and two underwent pre-ablation endovascular occlusion with an Amplatzer Vascular Plug IV. Three patients were temporarily anticoagulated pre- and post-endovenous laser ablation: one had underlying coagulopathy and two had a history of recurrent superficial venous thrombosis.

The aim of the endovenous laser ablation was achieved in 13 of the 15 patients (87%). In both patients in whom the aim of endovenous laser ablation was not achieved, it had been performed to facilitate sclerotherapy. Neither patient went on to have sclerotherapy: one had persistent symptoms and a patent vein on ultrasound at 43 days post ablation; the other underwent an attempt to perform sclerotherapy but had no accessible channels and symptoms persisted. Despite achievement of the clinical aim of endovenous laser ablation in 13 patients, long-term vein closure, assessed at follow-up imaging, was not always achieved. There was no imaging follow-up in one patient after two endovenous laser ablations to a single vein.

Eight patients with Klippel–Trenaunay syndrome (Table 1) were treated with the aim of improvement of pain or extremity swelling in five, cosmetic improvement of varicosities in two and to facilitate sclerotherapy by closing draining veins in one. Prior to endovenous laser ablation, all patients underwent venography to prove patency of the deep venous system and demonstrate anatomy of the target veins.

One patient undergoing endovenous laser ablation to an embryonic vein required two pullbacks of the laser to close the vein adequately (Fig. 2). One patient required repeat endovenous laser ablation of the greater saphenous vein because the lower end of the greater saphenous vein initially remained patent. Three patients had endovascular placement of an Amplatzer Vascular Plug II to close the intra-fascial deep cephalic component of the embryonic vein and prevent subsequent thromboembolism to the central veins. Two of these also underwent sclerotherapy with sodium tetradecyl sulfate (STS) foam (Sotradecol; Bioniche Pharma USA, Lake Forest, IL) at the time of endovenous laser ablation. Sclerotherapy with STS foam was undertaken in one patient 49 days post endovenous laser ablation to treat residual patency of the treated vein. Four patients received prophylactic peri-procedural anticoagulation. One patient had an inferior vena cava (IVC) filter placed at the same procedure as the endovenous laser ablation.

The aim of endovenous laser ablation was achieved in seven of the eight patients (88%) and partially achieved in one patient, who showed some improvement in pain and swelling with residual patency of the treated vein on follow-up imaging.

Five patients were treated for varicose veins (Table 1). Prior to endovenous laser ablation treatment, all patients had Duplex ultrasonography demonstrating superficial venous reflux. A total of seven greater saphenous veins were ablated. Endovenous laser ablation was commenced 2 cm below the sapheno-femoral junction in keeping with adult treatment recommendations [7]. In one patient endovenous laser ablation was done bilaterally; this patient had three veins (bilateral greater saphenous and an accessory greater saphenous vein) ablated over two endovenous laser ablation procedures. No adjunctive therapy was used at the time of treatment and none of these patients required anticoagulation.

The aim of the endovenous laser ablation was achieved in three of the five patients (60%). In the two patients where symptom improvement was not achieved, however, follow-up imaging did show vein closure. In one of these patients there was partial reduction in varicosities and in the other there was no improvement to the varicosity-related pain.

There were seven other patients, with a range of underlying diagnoses treated, with nine veins treated with endovenous laser ablation in eight procedures (Table 1). In one patient, endovenous laser ablation was used to close the draining vein of an arteriovenous fistula to facilitate subsequent direct glue embolization of the fistula (Fig. 3). Two patients were treated to reduce pain and swelling and to facilitate sclerotherapy of large superficial varicosities. Four patients with verrucous hemangiomas were treated, with the aim to facilitate sclerotherapy of verrucous hemangioma associated phlebectasia in two, facilitate surgical excision of the lesion in one, provide cosmetic improvement in one and reduce symptoms of pain and swelling in three (there was more than one indication in some patients). One patient with verrucous-hemangioma-related phlebectasia had two procedures: the first was to close an associated embryonic vein; however the patient remained symptomatic and was found to have a new enlarged embryonic vein, so this was closed at the second procedure. None of the treated veins required adjunctive closure techniques at the time of the endovenous laser ablation. Only the patient with the arteriovenous fistula received intra-procedural anticoagulation.

The aim of the endovenous laser ablation was achieved in six of the seven patients (86%). The patient in whom the aim of treatment was not achieved had a non-embryonic dysplastic vein partially closed at follow-up imaging; however symptoms of pain and swelling only resolved after the vein was ligated 199 days post endovenous laser ablation. In the six patients in whom the aim of treatment was achieved at follow-up, the treated veins were closed in two patients and partially closed in the remainder.

There were six complications following five procedures in five patients. Of these, two were directly attributable to the endovenous laser ablation procedure (6%, 95% confidence interval [CI] 0–13%). One was an episode of localized pain that resulted in extension of the patient’s hospital stay by 1 night (Society of Interventional Radiology category B, i.e. requiring nominal therapy with no consequence; Table 1). The other was a temporary cutaneous sensory nerve injury (Society of Interventional Radiology category A, i.e. requiring no therapy and with no consequence). This presented as sensory blunting noted at the first clinical follow-up 47 days post endovenous laser ablation to facilitate sclerotherapy in a patient with a venous malformation and subsequently resolved. The remaining complications were clinically determined to be unrelated directly to the endovenous laser ablation procedure and included: one temporary sensory nerve injury (Society of Interventional Radiology category A), which presented as altered skin sensation in distribution of sclerotherapy treatment, not endovenous laser ablation treatment; one 1-cm² area of ulceration in the popliteal fossa following endovenous laser ablation of an embryonic vein (Society of Interventional Radiology category B), which based on the location was thought to be caused by reflux of STS; one IVC perforation by the strut of an IVC filter placed at the same time as the endovenous laser ablation treatment (Society of Interventional Radiology category C, i.e. requiring therapy or minor hospitalization <48 h); and one episode of musculoskeletal chest pain (Society of Interventional Radiology category B), which presented to the emergency department and required a workup including a negative CT pulmonary angiogram.