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The purpose of the Southern Cross Medical Library is to provide information of a general nature to help you better understand certain medical conditions. Always seek specific medical advice for treatment appropriate to you. This information is not intended to relate specifically to insurance or healthcare services provided by Southern Cross. For more articles go to the Medical Library index page.

Hydrocoele - hydrocele

A hydrocoele (pronounced hi-dro-seel)) is the collection of fluid in the membranes surrounding the testicles, causing swelling in the scrotum. Hydrocoeles can be present at birth or affect infants and children; they may also occur in adolescents or adults as a result of infection, inflammation, or injury to the testicles.

Hydrocoeles are a common cause of scrotal swelling and do not cause any damage to the testicles.  Treatment can involve draining the fluid using a needle or minor surgery but often hydrocoeles will resolve themselves without treatment.

Signs and symptoms

A hydrocoele can occur on one side or on both sides of the scrotum but most commonly occur on the right side.  Apart from the scrotal swelling associated with a hydrocoele, other signs characteristic of the condition include:

  • A bluish discolouration of the skin if the hydrocoele is large
  • Fluctuation in the size of the swelling (mainly in infants)
  • The area of the hydrocoele is clearly defined
  • Hydrocoeles are not painful but may cause discomfort if they are large.


The doctor will carefully examine the scrotal swelling. Shining a light on the area will help differentiate a hydrocoele from others causes of swelling, such as an inguinal hernia.  With a hydrocoele the presence of fluid will cause the scrotum to light up when a light is shone on the area (transillumination).  In adolescents and adults, further diagnostic tests such as blood tests and ultrasound scanning may be recommended.


In infants, hydrocoeles may be the result of the passage through which the foetus’s testicle descends from the abdomen to the scrotum not sealing off properly, allowing fluid to flow from the abdomen into the scrotum. Most infant hydrocoeles resolve without treatment by the age of 12-18 months. If the hydrocoele persists for longer than 18 months, treatment is usually recommended.

In adolescents and adults treatment may not be required if the hydrocoele is small, the testes can be examined easily, and the amount of fluid remains constant. Treatment may be recommended if the hydrocoele is causing discomfort or embarrassment.

A hydrocoele can be treated by draining the fluid with a needle (aspiration) or by a minor surgical procedure.

To drain a hydrocele, a needle is inserted into the hydrocoele and the fluid is removed (aspirated). To prevent fluid reaccumulating after it has been drained, a special fluid called a “sclerosing” fluid may be injected into the scrotum after the hydrocoele has been drained. The sclerosing fluid helps to seal off the passage from the abdomen to the scrotum, preventing fluid from re-entering the scrotum. Recurrence is common after aspiration and sclerotherapy and the procedure can be painful.  therefor, it is usually a treatment of last resort.

Surgical removal of the hydrocoele (hydrocelectomy) may be recommended in cases where the hydrocoele is large and painful or where it has recurred after aspiration. This is a minor surgical procedure performed on a day stay basis. In infants a general anaesthetic is used. In adults a regional anaesthetic may be used.

During surgery a small incision is made in the scrotum or lower abdomen. The hydrocoele is drained of fluid and the membranes involved with the hydrocoele are removed. The incision is closed with small stitches. Surgery usually ensures permanent resolution of the hydrocoele.


Mayo Clinic (2014). Hydrocele (Web Page). Rochester, NY: Mayo Foundation for Medical Education and Research. [Accessed: 13/06/17]
O’Toole, M.T. (Ed.) (2013). Hydrocele. Mosby’s Dictionary of Medicine, Nursing & Health Professions (9th ed.). St Louis, MI: Elsevier Mosby.
Parke, J.C. (2017). Hydrocele (Web page). Medscape Drugs and Diseases. New York, NY: WebMD LLC. [Accessed: 13/06/17]
Last Reviewed – June 2017


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