Microvascular Doppler Assisted Microsurgical Denervation of the Spermatic Cord in Treating Chronic Orchialgia

Summary

Here, we present a protocol to treat chronic orchialgia by microsurgical denervation of the spermatic cord. Combined with the use of a microvascular doppler, the procedures can be more easily implemented.

Abstract

Chronic orchialgia is a common disease in department of urology and andrology. The etiology is complex, and the treatment is difficult. In severe cases, orchiectomy is even necessary. In recent years, microsurgical denervation of the spermatic cord (MDSC) is a minimally invasive and effective surgical method for the treatment of chronic orchialgia. Its greatest advantage is to preserve the testis and epididymis, avoid the possible organ resection. The key of the operation is to dissect all the fibrous tissues in the spermatic cord, while protecting the arteries (especially the testicular arteries) and several lymphatic vessels. Combined with the use of microvascular doppler in the operation, when separating the structure of spermatic cord under the microscope, the testicular arteries can be objectively and accurately protected (pulse “whistle” sound can be heard when the microvascular doppler probes the arterial surface), while artery injury and venous missed ligation can be avoided. The postoperative blood supply of the testis is also maximumly safeguarded. At the same time, we can be more fearless to cut the cremaster muscle, fatty and connective tissues surrounding the spermatic cord blood vessels and vas deferens after the arteries and lymphatic vessels being accurately protected under the microscope, finally achieve the spermatic cord completely "skeletonized" (only the testicular arteries, lymphatic vessels and vas deferens remained after the surgery). Thus we can better ensure the clinical curative effect (denervation thoroughly), avoid serious complications (testicular atrophy), and achieve better surgical results.

Introduction

Chronic orchialgia is a common disease accounting for about 2.5%–4.8% of all urology clinic visits¹, which has been defined as more than 3 months of unilateral or bilateral scrotal pain interfering with daily life that ultimately leads to the pursuit of treatment^2,3. The etiology is complex, and up to 50% of patients have no obvious etiology⁴. The exact mechanism is still unclear. Wallerian degeneration in peripheral nerves has been shown to be a potential cause of chronic pain^5,6.

Microsurgical denervation of the spermatic cord (MDSC) is an effective treatment for patients with chronic orchialgia after the failure of conservative treatments, especially for patients with a positive response to spermatic cord block (defined as greater than or equal to 50% temporary reduction of pain based on VAS)^7,8. The key to the operation is to dissect and ligate all the structures in the spermatic cord except the testicular arteries, a few lymphatic vessels, and the vas deferens⁹. Sometimes, it is difficult to divide small testicular arteries and the internal spermatic veins. It takes a bit more time to carefully dissect the arteries and preserve them.

We routinely combine the use of microvascular doppler during MDSC to avoid artery injury and venous missed ligation. A pulse “whistle” sound can be heard when the microvascular doppler probes the arterial surface while there is no sound in the veins. So, the difficulty of the surgery can be reduced, and the treatment outcomes can be improved.

Protocol

The protocol was conducted in accordance with the Declaration of Helsinki, and the protocol was approved by the ethics committee of the First Affiliated Hospital of Sun Yat-sen University. Chronic orchialgia patients who failed conservative treatment were admitted and signed informed consent.

1. Instruments for operation

1. Ensure the availability of the surgical microscope and microvascular doppler.

2. Preparation for operation

1. Clean and shave the inguinal/subinguinal skin and scrotum before surgery.
   NOTE: Before surgery, the surgical site need not be sterilized. As a routine procedure, soap is used to clean the inguinal/subinguinal skin and scrotum, and then a razor is used for shaving the area.
2. Let the patient lie on the operating table in a supine position after combined spinal-epidural anesthesia.
   NOTE: The anesthetist performs anesthetization. The anesthetization agents are mainly routine, while sometimes personalized. The choice and the dose of the anesthetic agent used are made by the anesthetist.

3. Procedure

1. Expose and lift the spermatic cord out of the incision.
   1. Perform a 2 cm oblique skin incision below the external inguinal ring with a circular scalpel.
   2. Then, dissect the spermatic cord and deliver it through the incision with the help of appendix forceps (see Figure 1).
2. Microsurgical varicocelectomy
   1. Bring an operating microscope into the operating field, and examine the cord under 8–12x power magnification.
   2. Use an electric knife to cut the external fascia and cremasteric fibers about 1 cm. Bluntly separate the internal spermatic fascia with its structures from the vas deferens and its vessels by a loop. Ligate the external spermatic vessels with 4-0 silk sutures.
   3. Drip 1% lidocaine solution on the spermatic cord. Use an intra-operative vascular Doppler flow detector (see Figure 2) to localize the internal spermatic arteries (pulse “whistle” sound can be heard when the microvascular doppler probes the arterial surface while there is no sound on the veins).
   4. Doubly ligate all of the internal spermatic veins with 4-0 silk ties and divide them. Accurately separate and preserve all identified arteries and lymphatics by loops (see Figure 3). Use microvascular doppler to distinguish arteries from veins when necessary.
3. Microsurgical denervation (see Figure 4)
   1. Next, carefully divide the anterior cremasteric muscle. Cut off the fatty and connective tissues surrounding the spermatic cord blood vessels and vas deferens completely with an electric knife. Identify and preserve the vas deferens and its associated vessels.
   2. Ligate and divide the vasal veins attached to the vas deferens when the vessels enlarge. Divide the posterior cremasteric fibers and fat components.
4. Finish the operation
   1. Skeletonize (only the testicular arteries, lymphatic vessels, and vas deferens remained after the surgery) the spermatic cord completely. Use the microvascular doppler to examine the testicular arteries again (see Figure 5).
   2. Then, manually place the cord back into the incision. Suture the deep tissue and skin.

Results

In total, 26 chronic orchialgia patients were admitted to the East Division of the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China, between March 2011 and June 2021 (Table 1). The average age of the patients was 39.9 ± 13.4 years. Within this group, 23 men underwent unilateral MDSC, and three men underwent bilateral MDSC successively. Prior to MDSC, all patients underwent spermatic cord block and had a positive response. The mixture we utilized comprises 5 mL of 2% lidocaine and ...

Discussion

Microsurgical denervation of the spermatic cord (MDSC) is a minimally invasive surgical option for treating chronic orchialgia after the failure of conservative treatments^7,8. Significant reduction or elimination of pain is reported in various studies; the pain relief rate is about 80%^4,10,11. Prior to MDSC, it is recommended that the patient undergo a spermatic cord blo...

Materials

Name	Company	Catalog Number	Comments
Surgical microscope	Leica	Model M520 MC-1	Leica operating microscope
Micro needle forceps	Cheng-He,NingBo	HC-A006	microsurgery instrument
Micro scissors	Cheng-He,NingBo	HC-A008	microsurgery instrument
Microscopic tweezers	Cheng-He,NingBo	HC-A002	microsurgery instrument
Microvascular doppler	VTI	VTI 20 MHz	intra-operative vascular Doppler flow detector