Hydrocele: what it is, symptoms, diagnosis and surgery

A hydrocele is a collection of clear fluid around the testis, between the two layers of the serous membrane (tunica vaginalis) that surrounds it. It causes an increase in the size of one or both sides of the scrotum, usually painless. It does not resolve on its own and tends to grow progressively, but it is cured by a surgical procedure. Diagnosis is simple and, in most cases, immediate.

Types of hydrocele

Two broad categories are classically distinguished: the primary (congenital) hydrocele and the secondary (acquired) hydrocele.

Primary or congenital hydrocele

This is caused by abnormalities in the descent of the testis from the abdominal cavity into the scrotum, and it is often associated with an inguinal hernia. Depending on how much of the peritoneal-vaginal canal remains open, several forms are distinguished:

• Communicating hydrocele: the vaginal cavity of the testis remains in communication with the peritoneal cavity
• Funicular-vaginal hydrocele: the part of the canal nearest the peritoneum closes, while the part below remains open
• Funicular hydrocele: only an intermediate segment of the peritoneal-vaginal canal remains open

Secondary or acquired hydrocele

This is the consequence of other processes affecting the testis or the epididymis:

• Infections, acute or chronic
• Trauma, including past, unnoticed or unrecognised injury
• Poor lymphatic drainage: in some cases habitually wearing overly tight clothing may contribute

Symptoms

A hydrocele presents as a usually painless increase in the size of the scrotum. As long as the fluid collection is small it causes no trouble; as it grows, its weight produces an uncomfortable sensation of tension or stretching.

The effusion progressively distends the vaginal cavity and can reach considerable volumes, even 500 ml, sometimes coming to interfere with urination and intercourse. On examination the skin is more or less taut according to the volume, but palpation is not painful. It is important to remember that the process does not resolve by itself: it tends to increase over time.

Diagnosis

• Transillumination test: this gives an immediate diagnosis. A small light source is placed against the scrotum; if the light passes through and is clearly visible on the other side, it is a hydrocele, because the contents are a clear fluid. This is what distinguishes a hydrocele from a solid mass, which does not transmit light
• Bilateral testicular ultrasound: the most specific investigation, confirming the diagnosis while assessing the testis and epididymis

Treatment: surgery

The treatment of a hydrocele is essentially surgical. The operation consists of eversion of the serous membrane surrounding the testis: the potential space between the two layers, where the fluid collects, is eliminated, thereby preventing the hydrocele from re-forming.

• Anaesthesia: it can be performed even under loco-regional anaesthesia
• Hospital stay: one or two days

Frequently asked questions about hydrocele

Is a hydrocele dangerous?

A hydrocele in itself is a benign condition: it is a collection of fluid, not a solid mass or a tumour. Nevertheless, any increase in the size of the scrotum should always be assessed by a specialist, precisely to distinguish a hydrocele from other conditions. The transillumination test and ultrasound serve exactly this purpose.

Does a hydrocele resolve on its own?

In adults, no: it does not heal spontaneously and tends to increase, which is why treatment is surgical. Some congenital forms in newborns, by contrast, may resolve in the first months of life — a situation to be assessed by a specialist.

How is a hydrocele distinguished from testicular cancer?

The first element is the transillumination test: a hydrocele, containing clear fluid, transmits light, whereas a solid mass does not. Confirmation comes from testicular ultrasound. Any increase in the size of the scrotum should always be assessed without delay.

Does a hydrocele affect fertility?

A hydrocele is a fluid collection outside the testis and does not in itself impair sperm production. It should, however, be distinguished from varicocele, which is a dilatation of the veins of the testis and does have a documented impact on fertility. They are two different conditions that the specialist must tell apart.

Can a hydrocele recur after surgery?

The eversion procedure is designed precisely to prevent the fluid collection from re-forming, by eliminating the space in which it accumulated. It is a definitive operation, with a short hospital stay of one or two days.

Have you noticed an increase in the size of the scrotum? Ask Prof. Natali for a consultation or book an appointment at his practices in Florence and Empoli, Italy.

The information on this page is provided for general educational purposes and does not replace a medical examination, which remains the only diagnostic tool for correct and effective treatment.