Is There an Increased Risk of the Vas Deferens Occlusion After Mesh Inguinal Hernioplasty and What Can We Do About It?

To the Editor:

Shin et al, in a recent multicenter study, highlighted the risk of the inguinal vas deferens injury after tension-free hernioplasty.¹ They observed obstructive azoospermia in 14 patients which led to infertility due to simultaneous, but different pathology of the reproductive organs of the contralateral side. The authors attribute the result to a robust fibroblastic process around the mesh, injuring and occluding the vas deferens.¹ In the same issue of Annals of Surgery, Fitzgibbons, in an editorial, made many pertinent comments with which we mostly agree.² He argues that there may not be a causal relationship between fibrosis around the mesh and vas obstruction since no such correlation was ever proven directly. It is true that obstructive vas deferens azoospermia can be also caused by intraoperative damage of the vas during dissection, suturing, or use of electrocoagulation.² As he fairly stated, there is also no doubt that the implantation of mesh in hernia repair surgery is a tremendous breakthrough, significantly reducing the recurrence rate and therefore decreasing the risk of spermatic cord injury during reoperation for recurrences.

However, both articles noted that the problem is the difficulty in clearly defining the extent of unilateral vas deferens occlusion. In most cases, such injury does not give any clinical symptoms and does not compromise fertility due to normal function of the contralateral testis or simply, in many patients, the fertility state is never evaluated after the operation. Patients presented in the multicenter study are those in which fertility was compromised due to bilateral reproductive system pathology, at least on one side due to vas deferens occlusion after hernioplasty. Therefore, it is also possible that these patients with clinical symptoms could be the tip of the iceberg of the patients with asymptomatic unilateral vas injury, which was never diagnosed.

It is very well established that the fibroblastic process around the polypropylene mesh is essential for posterior wall reinforcement but can also be harmful to organs in direct contact with the mesh, especially under pressure. Such fibrosis around the mesh can trap and damage inguinal nerves, intestine, urinary bladder, and can even occlude the urethra after polypropylene tape suspension in treatment of stress urinary incontinence.^3–6 Therefore, there is a very strong rationale that such processes can also involve the inguinal vasa when it is exposed to the mesh after dissection of the spermatic cord, and we should not ignore this situation. However, the reality remains that we do not know the actual complication rate due to rare clinical presentation.

Because of the above rationale and until the true complication rate is assessed, why not offer the option of an operation that limits the potential risk of vas deferens occlusion? This option might be extremely attractive to those with unilateral hernias and impairment of the contralateral testis or even to those patients who do not wish to risk compromise of their reproductive health.

One easy solution could be separation of the spermatic cord from the mesh. In the sutureless tension-free Trabucco technique, preshaped polypropylene mesh is placed on the posterior wall of the inguinal canal and the oblique aponeurosis is reapproximated below the spermatic cord, in contrast to other tension-free techniques. In this way, polypropylene mesh is placed flat between 2 fascial layers, the transversalis fascia and the oblique aponeurosis, which limits fibrotic tissue ingrowth into intrafascial space, leading to uniform, solid scar formation and preventing recurrence.^7,8 Oblique passage of the spermatic cord through the inguinal canal is not essential after this reinforcement of the abdominal wall.

With this technique, the spermatic cord is placed in the subcutaneous tissue, free from direct contact with the mesh and avoiding chronic inflammatory tissue. Long-term results of this technique are as superb as other tension-free repairs and are well described.^7–13 For those who prefer the Lichteinstein hernioplasty, reapproximation of the oblique aponeurosis below the spermatic cord, instead of over it, could also solve the problem of the potential vas injury complication. A randomized study could be performed to assess the effectiveness of such modification of the Lichteinstein technique, but in our opinion there is sufficient indirect evidence to support our thesis.

A hole for the spermatic cord in preshaped mesh instead of the shutter-valve effect of mesh tails sutured together could also decrease the contact of the mesh and the cord without compromising the effectiveness of the technique. The efficacy of this approach was clearly proven in the Trabucco technique and other repairs with utilization of the preshaped onlay mesh with a hole for the spermatic cord. The proposed surgical techniques comply with principles of the tension-free operation and can be easily implemented.

In summary, although the actual inguinal vas occlusion rate due to fibroblastic inflammation around mesh is not known now, there is a strong suggestion that such a process can take place and there is need to evaluate it. Therefore, in the meantime, all those patients with any compromise to their reproductive health or who are concerned about their fertility could be offered a surgical technique that minimizes the potential risk without compromising all the advantages of the tension-free hernia repair.

Piotr Witkowski, MD, PhD
Department of Surgery
Columbia University
New York, NY
Department of Surgery
Medical University of Gdansk
Poland

Ermanno E. Trabucco, MD
Trabucco Hernia Institute
New York, NY