Optimizing the Modified No-Scalpel Vasectomy Technique

Summary

A modified no-scalpel vasectomy technique reduces the postoperative recanalization rate. This protocol describes a modified no-scalpel vasectomy technique that can reduce the postoperative recanalization rate.

Abstract

No-scalpel vasectomy (NSV) is a commonly used contraceptive method for males. In previous applications of this surgical method, issues such as knot detachment and postoperative recanalization resulted in a reduced contraceptive success rate after vasectomy. This new technique innovatively modifies the ligation procedure during NSV to address knot detachment and postoperative recanalization. Two ligations of the testicular end of the vas deferens and one ligation of the abdominal end are completed before transection of the vas deferens. A fourth ligation of the abdominal end is performed using the suture tails of the third ligature of the testicular end after transection of the vas deferens. The fifth ligation of the abdominal end is performed using the suture tails of the first ligature of the testicular end. These modifications strengthen the ligations and reduce the postoperative recanalization rate. Additionally, the two stumps are gathered together, creating better conditions for a possible vasovasostomy in the future, thereby achieving overall better outcomes with vasectomy.

Introduction

Vasectomy is a surgical sterilization procedure for men to prevent future fertility^1,2,3. It is equally effective as tubal ligation for preventing pregnancy but is simpler, safer, faster, and less expensive⁴. This type of surgery has lower implementation requirements, and more than 80% of vasectomies are performed in the office⁵. Since 1971, when Li Shunqiang et al. performed the first modified vasectomy (the no-scalpel vasectomy or NSV)⁶, the procedure has advanced significantly. The invention of the extracutaneous vas deferens fixation ring clamp has reduced the number of surgical steps, while simultaneously minimizing surgical damage and the difficulty of the procedure¹. As a result, NSV has become the mainstream surgical method for vasectomy.

However, NSV still uses a single ligation and transection to seal the bilateral vas deferens ends, and the postoperative recanalization rate remains high. It has been reported that the occlusive failure rate after simple vasectomy is around 13.79%, and the postoperative recanalization rate is still 5.85% after vasectomy and fascial interposition⁷. As such, andrologists continue to explore improvements to vasectomy. Literature reports indicate that the postoperative recanalization rate can be reduced to 1% by using mucosal cautery on the ligated stumps⁸. Additionally, non-divisional vasectomy with extended electrocautery can further reduce the postoperative recanalization rate to 0.64%⁹.

However, for medical institutions lacking electrocautery equipment, reducing the postoperative recanalization rate remains a challenge. Therefore, the new technique proposes performing five ligations of the vas deferens without electrocautery conditions, building on the NSV method to reduce the postoperative recanalization rate. After five ligations, the formation of a vas deferens ischemic zone greater than 1 cm in length can increase the difficulty of vas deferens recanalization. This modified technique is also advantageous for exploring the ends of the vas deferens during future vasovasostomy. Compared to previous reports¹⁰, this modification does not require electrocautery equipment during surgery, thereby reducing equipment requirements. This approach can help operating rooms without electrocautery equipment to perform a vasectomy.

Protocol

The surgical method described in this paper has been approved by the Ethics Committee of the West China Second University Hospital of Sichuan University, and the use of patient surgical videos has been authorized. Informed consent was obtained from the patients, and their data was used for presentation. The consumables and equipment used for this study are listed in the Table of Materials.

1. Preparation for operation

1. Use the following inclusion criteria to select participants for the study:
   1. Adult males who have opted for sterilization.
   2. Ensure preoperative color Doppler ultrasonography¹¹ reveals normal bilateral vas deferens development in the patients.
   3. Exclude any individuals with diseases that could affect the safety of the surgery, such as poorly controlled hypertension, hyperglycemia, or respiratory diseases.
2. Apply the following exclusion criteria to exclude participants from the study:
   1. Exclude patients with severe coagulopathy or other contraindications to anesthesia.
3. Perform skin preparation before surgery.

2. Surgical procedure

1. Stand on the right side of the patient and perform bilateral spermatic nerve blocks using 2% lidocaine. Apply pressure for 1 min to stop bleeding and reduce local edema.
2. Use the three-finger technique⁶ to fix the right vas deferens beneath the median raphe. Firmly trap the vas deferens under the thumb and index finger of the left hand and over the middle finger for fixation.
3. Flatten the scrotal skin over the vas deferens, and clamp the vas deferens using an extracutaneous vas deferens fixation ring clamp with the right hand.
4. Maintain the ring clamp in a clamped state and pass it from the right hand to the left. Secure the ring clamp with the left thumb, middle, and ring fingers.
5. Press the scrotal skin downward with the left index finger while simultaneously elevating the ring clamp to tighten the skin over the vas deferens using the left thumb, middle, and ring fingers.
6. Use one blade of the dissecting clamp to puncture the skin and vas sheath, then withdraw the dissecting clamp.
7. Close both blades of the dissecting clamp and reinsert it through the same puncture hole. Gently open the clamp to separate the scrotal skin by about 1 cm.
8. Use the right blade of the dissecting clamp to pierce the most superficial and prominent part of the vas deferens wall. Rotate the dissecting clamp 180 degrees laterally.
9. Release the extracutaneous vas deferens fixation ring clamp with the left hand. Elevate the dissecting clamp and extract the right vas deferens from the body.
10. Grasp the delivered vas deferens with the ring clamp using the left hand. Gently isolate the right vas deferens artery with the dissecting clamp, exposing a clean segment of about 2.5 cm.
11. Pull the ring clamp toward the abdominal side and straighten the vas deferens. Use a 3-0 silk suture to complete the first ligation at the testicular end of the vas deferens.
12. Pull the ring clamp toward the testicular side and perform a second ligation on the abdominal side, 1.5 cm from the first ligation.
13. Tighten the suture tails of the first ligation toward the testicular side and pull the ring clamp toward the abdominal side.
    NOTE: The bare vas deferens should now be clearly visible.
14. Use the dissecting clamp to clamp the right vas deferens 1 cm from the first ligation on the abdominal side. Release the extracutaneous vas deferens fixation ring clamp.
15. Complete a third ligation between the dissecting clamp and the first ligation. Transect the right vas deferens tightly against the abdominal side of the dissecting clamp.
16. Rotate the dissecting clamp 180 degrees and pull the tails of the second ligation toward the testicular side over the dissecting clamp and the first ligation.
17. Perform a fourth ligation on the abdominal side of the right vas deferens, 1 cm from the second ligation, using the suture tails from the third ligature.
18. Pull the suture tails of the second ligation toward the testicular side and those of the fourth ligation toward the abdominal side. Perform a fifth ligation between the second and fourth ligations using the suture tails from the first ligation (Figure 1).
19. Ensure there is no bleeding in the surgical area. Cut off the ends of the three sutures.
20. Pull the right testis toward the testicular side through the scrotum, and reposition the right vas deferens with the anatomical reduction in the scrotum.
21. Repeat the procedure on the left vas deferens and suture the scrotal incision with 5-0 absorbable sutures.

3. Postoperative care and follow-up

1. Change the dressing every 3 days after surgery, and remove the sutures 1 week later.
2. Instruct patients to refrain from ejaculation for approximately 2 weeks after the vasectomy.
3. After 2 weeks, advise them to ejaculate regularly, twice a week. Perform post-vasectomy semen analysis (PVSA) after 20 ejaculations¹².

4. Statistical analysis

1. Analyze all data statistically using statistical data analysis software.
2. Use a t-test for data conforming to a normal distribution and a non-parametric test for data not conforming to a normal distribution. Consider statistical differences significant when P < 0.05.
3. Present results as mean ± SD for data conforming to a normal distribution and as medians with interquartile ranges for data not conforming to a normal distribution.

Results

From January 2021 to August 2023, 58 vasectomies were performed at this hospital. All 58 patients had at least one child with their spouses before undergoing vasectomy. Although the modification involved more surgical steps compared to NSV, it did not significantly increase the difficulty of the operations. As a result, all 58 vasectomies were successfully completed without any unsuccessful operations. Patients were followed up regularly by telephone. Follow-up ended when the PVSA demonstrated less than 2,00,000 sperm/mL. If more than six months after the vasectomy, a patient impregnated his wife or the last PVSA showed more than 2,00,000 sperm/mL, it was designated as recanalization.

In the NSV group, all 24 vasectomies were successfully performed. Three patients experienced recanalization after vasectomy. Four patients had incomplete data: three declined the PVSA, and one refused phone calls. The remaining 17 patients had complete data, with ages ranging from 23-47 years (median 35 years), and a follow-up period ranging from 1-25 months (median 9 months). None of the patients reported any discomfort after surgery.

In the modified group, all 34 vasectomies were successfully performed after the NSV group. However, it is regrettable that 10 patients declined the PVSA. A total of 24 patients had complete data, with ages ranging from 28 to 46 years (median 33.5 years), and a follow-up period ranging from 1-17 months (median 2.5 months). Only one patient reported chronic left scrotal pain. None of the 57 patients who answered the phone had undergone vasovasostomy.

No significant difference in age was found between the two groups (p > 0.05), indicating that both groups were within the same age range. However, there was a significant difference in follow-up duration (p < 0.05), suggesting superior adherence in the modified group. It is possible that a longer surgical time encourages patients to be more attentive to postoperative follow-up. The last PVSA was performed more than 11 months after the vasectomy, and the sperm concentrations were over 25,000,000 sperm/mL in the three patients who experienced recanalization in the NSV group. Two of the 24 patients in the NSV group (one of whom refused phone calls) impregnated their wives, while the patients in the modified group were deemed sterile. The follow-up results of the modified group were significantly better than those of the NSV group. The demographic information of the patients is displayed in Table 1.

Figure 1: Location and relationship of the 5 ligations. The figure illustrates the location and relationship of the five ligations used in the procedure. The modification technique interlaces the two ends of the vas and binds them together. Please click here to view a larger version of this figure.

Items		NSV	The modification	P  value
Patients		24	34
Patients were recanalized after surgery		3	0
Patients rejected the PVSA		3	10
Patients impregnated their spouses after surgery		2	0
Patients refused phone calls		1	0
Patients whose spouses have completed childbirth before surgery		24	34
Patients had complete data		17	24
The Age of patients had complete data, year		35 (32,36)	33.5 (30.5,35)	0.408
The end of the follow-up,months		9 (3,13.5)	2.5 (1,4)	0.001
Postoperative complications		0	1

Table 1: Demographic data. Statistical differences were considered significant when P < 0.05. Abbreviations: PVSA = post-vasectomy semen analysis.

Discussion

The gold standard for vasectomy is ligation with mucosal cautery¹³, but not all operating rooms have electrocautery equipment. Therefore, this modification technique achieved ideal surgical results by ligating the vas deferens five times with non-absorbable silk sutures, without the need for electrocautery equipment. It has been documented that applying excessive pressure to the vas with sutures can create ischemia and sloughing of the ligated stump, leading to recanalization. This may explain some of the higher failure rates associated with these methods¹⁴. The most significant modification compared to NSV is the repeated ligation-two times at the testicular end and three times at the abdominal end. Additionally, the third and fourth ligations use the same suture, as do the first and fifth ligations, to minimize the sloughing of the knots.

In addition, histological studies of vasectomy sites after failure have reported that one or more channels (canaliculi) can form through the connective and scar tissue between the vas stumps, allowing the passage of sperm, especially in cases of chronic inflammation¹⁵. The critical step of the modification technique is interlacing and binding the two ends of the vas together, which results in the separation of the two transected sections. Consequently, an ischemic region of at least 1 cm is formed, making natural recanalization more difficult in the future.

Moreover, some patients may reconsider natural paternity after vasectomy due to events like the death of a child, divorce, or remarriage¹⁶. This modification technique, which binds the two vas stumps together, creates better surgical conditions and makes it easier to locate the vas ends when performing vasovasostomy in the future.

The limitation of this modification technique is that the operation time is longer than that of NSV due to repeated ligations. The modified vasectomy lasted approximately 30 min; however, no additional anesthetics were needed during the surgery. The longer operation time may lead patients to pay more attention to the procedure and improve adherence.

In summary, this modification technique could result in better outcomes for vasectomy, particularly in operating rooms without electrocautery equipment.

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
3-0 silk braided non-absorbable suture	Johnson & Johnson Medical (China) Ltd.	SA84G	15 × 60cm
5-0 Coated VICRYL Plus (Polyglactin 910) Synthetic Absorbable Suture	Ethicon.Inc.	VCP433H	13 mm 1/2c (70cm)
Dissecting clamp	Xinhua Surgical Instruments Co., Ltd.	ZJ197R	125 mm
Extracutaneous vas deferens fixation ring clamp	Xinhua Surgical Instruments Co., Ltd.	ZJ196R	140 mm
Scissors	Xinhua Surgical Instruments Co., Ltd.	ZC344R	140 mm
SPSS 23.0	IBM