Varicoceles are felt to play a major role in male infertility. In order to understand what a varicocele is, some basic information about anatomy and physiology is essential.The testicles are the paired male genital organs that contain not only sperm but also cells that produce and nourish the sperm. These organs are located in a sac called the scrotum. The epididymis is a small, tubular structure attached to the testicle. It is the reservoir where the sperm mature and are stored. The vas deferens connects the epididymis to the urethra and is the tube through which sperm travel during ejaculation. The vas deferens is not situated by itself but is a part of a larger tissue bundle called the spermatic cord. The spermatic cord contains many blood vessels as well as the vas deferens, nerves and lymphatic channels. The veins of the spermatic cord are known as the pampiniform plexus. These veins drain blood from the testis, epididymis and vas deferens, eventually becoming the spermatic veins that drain into the main circulation at the level of the kidneys.
What causes a varicocele?
A varicocele occurs when the pampiniform plexus of veins becomes twisted or tortuous and dilated, much like a varicose vein of the leg.
How is a Varicocele related to male fertility?
The varicocele is a well-recognized cause of decreased testicular function and is present in about 40% of infertile males. The association between varicoceles and infertility was first proposed in the late 19th century, and it was confirmed in the early 1900s. A pattern of low sperm count, poor motility and a predominance of abnormal sperm forms were documented with the presence of varicoceles. Although varicoceles appear in about 15% of the normal fertile male population, their presence is significantly higher in the sub-fertile male population. In fact, scrotal varicoceles have been found to be the most common identifiable and surgically correctable factor that contributes to poor testicular function and decreased semen quality.
Varicocele Anatomy and the Effect on the Testicle
Varicoceles are more common on the left side that on the right for multiple anatomic reasons. They may vary in size and can be classified into 3 groups: (1) LARGE varicoceles that are easily identified by visual inspection alone, (2) MODERATE varicoceles that are identified by palpation without bearing down, and (3) SMALL varicoceles that can be identified only by bearing down which increases intra-abdominal pressure, further impeding drainage and thus increasing the size of the varicocele.It is important to remember, however, that the size of the varicocele is not related to the degree of changes in the sperm.
Several theories have been proposed to explain the deleterious effect of the varicocele on sperm quality. These include oxygen deprivation, increased testicular temperature or metabolic toxins. Despite considerable research, none of these theories has been proven beyond doubt. However, the effect of increased heat caused by impaired circulation appears to be the most reproducible cause of damage to sperm quality. The fact that creation of varicoceles in experimental animals leads to poor sperm function with elevated intra-testicular temperature supports this concept.
Diagnosis of a Varicocele
It is critically important to identify a varicocele on physical examination because of its potential role in damage to the testis and impact on sperm quality .Reasons for surgical correction include the presence of significant testicular pain, impairment of testicular function as evidenced by decreased semen quality and loss of testicular size (atrophy).The mere presence of a varicocele does not mean that surgical correction is necessary. Usually, the varicocele is asymptomatic in the patient seen primarily for evaluation of male fertility. However, the patient may sometimes complain of pain or heaviness in the scrotum, the old sore nuts syndrome.
Careful physical examination remains the primary method of varicocele detection. It is important to examine the patient in the standing position, having him perform the Valsalva maneuver (that is, take a deep breath and bear down) to magnify a small varicocele.When small varicoceles are difficult to diagnose, more objective means can be used, such as ultrasonography and venography. Ultrasound is painless and evaluates dilation of the peritesticular veins using sound waves. Venography requires a small incision in the groin, insertion of needle into a groin vein and injection of “dye” (contrast solution) which will flow into the spermatic vein. This technique is performed on an outpatient basis and allows direct visualization of the varicocele by x-ray.
Varicocele Surgery and Its Results
Once a varicocele is diagnosed, reasons for surgical correction include: testicular discomfort or pain unrelieved by routine, symptomatic treatment, testicular atrophy (shrinkage), or the possible contribution to unexplained male infertility.
There are two commonly used surgical approaches for the correction of a scrotal varicocele: (1) the transinguinal (groin) approach and (2) the retroperitoneal (abdominal) approach (3) and in case of bilateral varicocels, the laparoscopic approach. Under routine conditions, the transinguinal approach is the operation of choice. The retroperitoneal approach is used in patients who have already had an attempted varicocele or hernia repair where considerable scaring may be encountered.
Although the mechanisms whereby varicoceles cause impairment of sperm production and semen quality remain incompletely understood, the association between varicocele and male infertility is unquestionable. Furthermore, improvement in semen quality after varicocele correction has been repeatedly demonstrated. The resultant improvement in semen quality occurs in about 67% of patients, with the most improvement seen in sperm motility rather than in sperm count. The pregnancy rate is as high as 40%, with the pregnancy occurring on an average of 6-9 months following surgery.
The scrotal varicocele remains the most common correctable factor when treating decreased semen quality. Therefore, when present in the infertile male with abnormalities of semen quality, surgical correction should be strongly considered. The side effects following varicocele repair are remarkably low, and successful surgery will often increase the incidence of eventual pregnancy in the infertile couple.