Hydrocele

The scrotum is normally loose, soft, and fleshy. It holds the two testes. Usually you can easily feel the testes in the scrotum. A tube (the vas) takes sperm from each testis to the the penis. It is normal for one testis to hang lower than the other.

What is a hydrocele?

A hydrocele is a collection of fluid in a sac in the scrotum next to a testes (testicle). It usually occurs on one side, but sometimes a hydrocele forms over both testes.

The normal testis is surrounded by a smooth protective tissue sac. You cannot normally feel this. It makes a small amount of 'lubricating' fluid to allow the testes to move freely. Excess fluid normally drains away into the veins in the scrotum. If the balance is altered between the amount of fluid that is made, and the amount that is drained, some fluid accumulates as a hydrocele.

What do hydroceles look and feel like?

A hydrocele feels like a small fluid filled balloon inside the scrotum. It feels smooth, and is mainly in front of one of the testes. They vary greatly in size. Very large hydroceles are sometimes seen in elderly men who have never shown their swelling to a doctor. It might have been getting larger over a number of years.

Hydroceles are normally painless. Large hydroceles may cause discomfort because of their size. Walking or sexual activity may become uncomfortable if you have a very large hydrocele.

Most hydroceles occur in adults and are most common in older men.

• The cause is not known in most cases.
• A small number of hydroceles are caused when something is wrong with one of the testes. For example, infection, inflammation, injury, or tumours of a testis may cause fluid to be formed which leads to a hydrocele forming.

Some babies are born with a hydrocele. One often occurs if the baby has a hernia and both are usually fixed soon after birth by a surgical operation.

Do I need any tests?

Usually not. A doctor will want to check that the testes are healthy. If the hydrocele is large, and the doctor cannot feel the testis, the fluid can be drained with a needle and syringe. (This is helped by injecting local anaesthetic into the overlying skin to make the procedure painless.) Once the fluid is removed, the testes can be examined more easily. Sometimes an ultrasound scan of the testes will be advised. This can check the testes to make sure there is no underlying cause for the hydrocele.

• Leave alone. If the hydrocele causes no symptoms one option is simply to leave it alone. If it becomes larger or troublesome, you can always change your mind.
• Drainage. The fluid can be drained easily with a needle and syringe. However, it is common for the sac of the hydrocele to refill with fluid within a few months. Draining every now and then may be an option if you are an older person and not fit for surgery, or if you do not want an operation.
• Surgery. Hydroceles can usually be cured with a relatively simple surgical operation.

(Most hydroceles occur with normal testes. In the rare situation of an underlying disease of a testis causing the hydrocele, other treatments may also be advised.)

© EMIS and PIP 2004   Updated: May 2002   CHIQ Accredited   

The authors and editors of this article are employed to create accurate and up to date content reflecting reliable research evidence, guidance and best clinical practice. They are free from any commercial conflicts of interest.

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