Percutaneous varicocele embolization

Introduction

The treatment of varicocele by percutaneous embolization of the internal spermatic vein is a safe and effective minimally invasive procedure. Its very low morbidity and complication rates, high long-term success rates and demonstrated cost effectiveness relative to surgery have led some authors to argue that percutaneous embolic techniques should be the primary therapy to treat varicoceles, or at least a viable and valuable alternative to surgical options.^1,2,3,4,5

Technique

Percutaneous embolization of varicocele requires selective catheterization of the internal spermatic vein(s) followed by its occlusion with either a sclerosant or solid embolic devices.⁶ Although many devices and agents have been described for this purpose, current techniques use predominantly coils (stainless steel or platinum) as the solid embolic agent, sodium tetradecyl sulfate as the sclerosant or a combination of the 2.

The procedure is performed on an outpatient basis under local anesthesia. Conscious sedation with titrated doses of intravenous midazolam and fentanyl can be used if required. The patient is placed supine on the angiography table, and gonads shielded from irradiation. Aseptic conditions are used. The procedure is performed from internal jugular or common femoral venous approaches; the selected access vein is punctured under ultrasound guidance. Using the Seldinger technique, an appropriate catheter (typically 5–7 Fr in size) is used to select the left renal vein. Some interventional radiologists advocate initial left renal venography to demonstrate reflux of contrast into left internal spermatic vein due to incompetent valves and to delineate potential collateral pathways, while others proceed to selection of the left or right internal spermatic vein and internal spermatic venography. The catheter is advanced retrogradely down the internal spermatic vein to just above the inguinal ligament level. Venography is performed to document the position of the catheter before commencing embolization, as well as assess the size of the internal spermatic vein and the presence of any collateral circulation.

If coils are being used, embolization is commenced at this level, with additional coils deployed in the more cephalad internal spermatic vein extending to near its junction with the left renal vein or inferior vena cava (for right internal spermatic vein) so that the coils occlude the main branch and all accessible collaterals. To minimize the risk of recurrence, it is necessary to isolate the most distal (caudal) segment of the internal spermatic vein from any potential collateral supply. In some patients, collateral parallel channels must be selectively catheterized and occluded.

When sclerosants are used, the technique is similar, with care taken to apply external pressure at the inguinal crease when injecting the sclerosant to prevent reflux into the pampiniform plexus. The Trendelenburg position can also be used to decrease the risk of reflux into the pampiniform venous plexus.

If a combination of coils and sclerosant are being used (referred to, by some, as the “sandwich” technique), coils are placed in the distal internal spermatic vein just above the inguinal ligament level. The purpose of the coils is to prevent reflux of sclerosant into the pampiniform plexus, and is in addition to the previously described maneuouvres. Sclerosant is then injected slowly along the length of the internal spermatic vein while withdrawing the catheter, followed by placing coils in the cephalad internal spermatic vein.

Postprocedure hemostasis is achieved at the puncture site with manual compression. The patient is observed for approximately 2–3 hours post procedure before being discharged home. Patients are typically able to return to work the following day, but are advised to avoid heavy lifting and contact sports for 5–7 days.

Results

In recently published studies, technical success rates are 92.4%⁷–96%.⁸ Recurrence rates are < 2%⁸–4%⁹ among those referred for infertility. In the pediatric and adolescent population, long-term recurrence rates in those for whom the procedure was initially technically successful are as low as 7%⁵ and 11%.¹⁰ Most of the patients in the quoted studies have unilateral left-sided varicoceles, though right-sided varicoceles are included in the results. The rates of technical success and recurrence rates in the recent literature have improved, compared with previously published studies in the 1980s and early 1990s. This is owing to improvements in techniques, increasing expertise in the area and improved equipment including catheters, coils and contrast media.⁸

With regard to outcomes in the treatment of varicoceles in the infertile or subfertile population, the improvements in seminal parameters and pregnancy outcomes are equivalent in patients who have undergone percutaneous embolization versus surgical ligation.^3,9,1`1 Reyes and colleagues found the long-term success and complication rates of percutaneous embolization of adolescent varicocele comparable to those with surgical ligation.⁵

The complications of percutaneous therapy are infrequent and typically mild.¹² Complication rates in recent literature have been reported from 0%,⁸ to 5%⁵ and 11%.⁹ Thrombophlebitis of the pampiniform plexus is a potential complication when sclerosants are used; Wunsch and colleagues report its occurrence in 0.5% of cases,¹ and it requires treatment with anti-inflammatories and antibiotics. It is prevented by compression at the inguinal crease or by using coils at the outset. Coil migration is a rare complication that is always linked to excessively distal release. Reported cases to date have been asymptomatic.⁶ Hydrocele and testicular atrophy are not potential complications with embolization techniques.

Exposure to ionizing radiation during image guided percutaneous therapy is a potential concern given the procedure is typically performed on healthy young males with normal life expectancy and the future potential to reproduce.¹³ Studies have shown that if proper techniques are used (shielding the gonads, avoiding exposure of the scrotum to the primary beam, collimation of beam to smallest practical area, and using pulsed fluoroscopy and image capture to minimize angiographic runs and spot images), doses are within the range of other diagnostic procedures such as CT scan, and gonadal dose values are low enough to exclude induction of deterministic and hereditary effects.⁷

Benefits

The benefits of percutaneous embolic therapy for varicocele extend beyond its high technical and clinical success rates, equivalency to surgical therapies in terms of outcomes and very low complication rates. It is a minimally invasive, outpatient procedure that allows quick patient recovery, minimal discomfort compared with surgery, and shorter time to return to work (typically within 1–2 d) and full activities.³ It is cost effective relative to surgery in that the procedural costs are less or similar, but embolization has the financial advantage in that shorter recovery time minimizes inconvenience and loss of potential working days.³ Feneley and colleagues showed that patients who underwent both embolization and surgical ligation expressed a strong preference for embolization.² Additional advantages to the embolization approach are that bilateral varicoceles can be treated at a single setting via the same venous access, and that it has a high technical success rate in treating recurrent varicoceles post surgical ligation.⁵

Conclusion

Percutaneous embolization of the internal spermatic vein to treat varicoceles is a minimally invasive outpatient procedure that, when performed by experienced interventional radiologists, has high technical success rates, low recurrence rates, very low morbidity and minimal radiation. It has been demonstrated to be equal to surgical ligation in clinical results and as or more cost effective. Its minimally invasive nature allows it be well tolerated with shorter recovery times and less discomfort relative to surgery. When skilled and experienced vascular and interventional radiology services are available, embolization is an effective alternative to surgery and should be offered as such or as primary therapy for varicocele treatment.