Introduction
Varicocele is the commonest cause of male factor infertility[
1]. Varicocele is abnormal elongation, dilatation and tortuousity of spermatic vein [
2]. Clinical varicocele is found in up to 20% of general male population, in up to 40% of males with primary infertility and in up to 80% of men with secondary infertility [
3]. Varicocele is associated with duration dependent and progressive insult to testicular function[
4]. The testicular insult from varicocele impairs all indices of sperm function i.e. sperm density, sperm motility, sperm morphology, sperm vitality and semen volume[
3]. These changes in semen parameters are multifactorial in aetiology. They have been attributed to varicocele related disturbance in testicular thermoregulation[
5,6], hemo-stagnation in testicular veins leading to hypoxia[
7], reflux of adrenal metabolites [
8], dilution of intra-testicular substrates [
9], higher levels of sperm derived reactive oxygen radicals [
10,11,12] ,nitric oxide [
13] and regulators of apoptosis [
14]. Apart from dys-spermatogenesis varicoceles reduce Leydig cell function and decrease the testicular volume [
15]. Ablation of varicocele is associated with improvement in semen variables and a higher natural pregnancy rate and improved male fertility potential [
2]. Treatment of varicocele is shown to improve vas deferens mobility which has been disturbed by presynaptic neuromediator disruption [
16]. Not only the varicocele repair improve semen parameters in oligospermia but it can improve the sperm harvest from testicular extraction in patients of non-obstructive azoospermia [
2] .
Clinical manifestation of Varicocele
Apart from being commonest correctable cause of male factor infertility [
17] varicocele may cause scrotal discomfort, orchalgia, inguinodynia, dysejaculation and erectile dysfunction[
18]. Apart from these, varicocele correction is indicated in asymptomatic varicoceles for bilateral stage 3 disease, involvement of solitary testicle, poor semen parameters in Tanner V adolescent in those with risk prediction as defined by Kozakowski’s criteria [
19] based upon Hirsh grading[
20].
Laterality of Varicocele
Clinical varicoceles are more common on left side. Predisposition of left side has been attributed to venous valvular dysfunction (lack of valves, low density of valves, or valvular incompetence), disruption of ‘cord – covering driven’ venous pump, right angled insertion of the vein, compression between aorta and superior mesenteric artery, transmission of sigmoid colon pressure, higher catecholamine concentration and the relatively straight course of left vein leading to ‘proximal – distal’ nut cracker phenomena [
21,22] . However various authors have reported bilaterality of varicoceles in more than 75% patients [
22]. Bilaterality concept is further supported by studies showing greater improvement in semen parameters and natural pregnancy rates following bilateral varicocelectomy [
23]. Variations on the left side vein were previously thought to be more common (5 types) [
24] but they have been shown to be equally prevalent i.e. 5-6 types on the right side as well [
22]. Most of the available anatomical data is based up ton cadaveric studies. Now with the possibility of studying live anatomy, as in endosurgery new insights have emerged. It has been shown that apart from variations which are equally prevalent on either side, collateral venous channels are more common and greater in number on the left side [
25]. Vascular dynamics of living anatomy are more relevant to surgery and are much different than the understanding gathered from the cadaveric anatomical studies [
26].
Goals of varicocele surgery
Reversal of pathophysiological insult to the testicular and allied functions can be reversed by a guaranteed abolition of the venous reflux while ensuring a physiological venous drainage. Varicocele surgery should preserve physiological arterial flow and avoid any insult or damage to the lymphatic structures and regional nerves. Apart from understanding the anatomy of the region, an emphasis on safe surgical practices is paramount to ensure better clinical and patient reported outcomes. This can be achieved by relying upon sharp dissection, utilizing the concept of surgical holy planes and avoiding any use of energized dissection. Energized dissection in varicocele surgery has been shown to cause inadvertent injuries to important structures including vas and nerves. Proper understanding of anatomy goes a long way in minimizing failure and complications which are shown in Table 1.
Table 1 - Follow up strategy for varicocele
Vasculature of the testis [27]
Arterial supply [Figure 1]
Internal spermatic artery, a branch of abdominal aorta is the primary source of blood to testis. Internal spermatic artery and the deferential artery (arising from division of internal iliac artery) anastomose around the cauda epididymis. Blood supply to the testis is also contributed through the connections to this anastomosis from the external spermatic (cremastric) artery, arising from the external iliac artery via the inferior epigastric artery. The arterial anastomosis around the cauda epididymis is responsible in sustaining the arterial supply despite the artery ligation in classical varicocoelectomy. Artery preserving or artery ligating procedures have similar outcomes, though the debate goes on [
28]. However in cases where collateral arterial supply may be compromised by the previous inguino-scrotal-pelvic trauma or surgery, it is desirable to spare the testicular artery during varicocoelectomy.
Figure 1 Arterial supply of the testis
Venous drainage
The veins corresponding to the various arteries coalesce to form pampiniform venous plexus. Pampiniform venous plexus courses along the testicular artery in a reverse branching fashion. The number of veins thus decrease as they travel cephalad. Cranial to the internal inguinal ring, the number decreases to 1 or 2 and finally a single testicular vein drains in to inferior vena cava on the right side and into the renal vein on the left side. Some veins course along the vas deferens draining into the vesical plexus. Some of the veins course and drain into the saphenous vein following the cremastric vasculature. In addition to these there are collateral venous channels running parallel in the inguinal canal, channels running along the gubernaculum, channels running to the inferior epigastric vein and some veins drain into various pelvic floor tributaries as well [
29] . Ablation of these venous channels is pertinent in ensuring the success of varicocelectomy. Apart from these, trans-scrotal collateral venous channels, venae commitantes of arteries and venae nervosum of nerves are also involved. These are important in maintaining the physiological venous drainage after varicocelectomy.
Lymphatics
Postoperative hydrocele is a common complication of the varicocelectomy with a reported incidence of up to 40% [
30] . Hydroceles however remain clinically undetectable during the initial six months. Most of the hydroceles manifest after 6 months and up to 3 years [