Hydrocele

A hydrocele is a fluid-filled swelling that occurs in the scrotum, the pouch of skin that holds the testicles. While the swelling can be alarming, hydroceles are usually painless and often harmless, particularly in newborn babies where they commonly resolve on their own within the first year of life.

Table of contents

• What is a hydrocele?
• Types of hydroceles
• Associated anatomy
• What causes a hydrocele?
• Who is affected by hydroceles?
• Symptoms of hydrocele
• How is a hydrocele diagnosed?
• Treatment options
• Recovery after surgery

What is a hydrocele?

A hydrocele is a painless buildup of watery fluid around one or both testicles that causes the scrotum or groin area to swell^[1]. The swelling happens when fluid collects in the thin sac that surrounds a testicle^[1]. This sac is known as the tunica vaginalis, which directly surrounds the testis and spermatic cord^[2].

Although hydroceles are common in newborns, they can also occur at any age in later life^[1]. The swelling may be unsightly and uncomfortable, but it usually is not painful and generally is not dangerous^[4]. The main symptom is often a swelling that may feel like a water balloon^[8].

• Scrotum
• Testicles (testes)
• Tunica vaginalis
• Spermatic cord
• Inguinal canal
• Epididymis

Types of hydroceles

Hydroceles are divided into two main types: communicating hydroceles and noncommunicating hydroceles^[8].

Communicating hydrocele: This type has contact with the fluids in the abdominal cavity. During fetal development, a thin membrane called the processus vaginalis forms between tissues in the stomach lining and the scrotum. Normally, the testicles slide down from the abdomen through this membrane into the scrotum, and tissue then forms to seal the opening^[8]. When this opening does not close properly, fluids from the abdominal cavity can flow into the scrotum and cause a hydrocele^[8]. The communication allows the movement of fluid but is too small to allow abdominal contents to herniate through^[2]. If a communicating hydrocele is present, the scrotum may appear large or swollen, and it may change in size throughout the day^[8].

Noncommunicating hydrocele: In this type, the processus vaginalis closes, but some extra abdominal fluid remains around the testicle in the scrotum^[8]. This happens when the sac closes but the fluid is not absorbed by the body^[12]. Noncommunicating hydroceles may be present at birth or develop years later for no obvious reason^[8]. If this type is present, it usually remains the same size or grows very slowly^[8].

Depending on the site where the processus vaginalis closes, there are additional types of primary hydrocele, including infantile hydrocele, encysted hydrocele of the cord, and vaginal hydrocele^[2].

What causes a hydrocele?

The cause of most hydroceles is unknown^[4]. In newborns, hydroceles may mean there is an opening between the abdomen and the scrotum. Normally such openings close before birth or shortly after^[4]. Hydroceles in newborns are part of fetal development, when abdominal fluid can flow into the scrotum if the processus vaginalis does not close. Sometimes, even if the processus vaginalis closes, abdominal fluid may remain in the scrotum, and the child’s body usually absorbs this fluid within the first two years^[8].

Hydroceles that appear later in life may be caused by an injury or surgery to the scrotum or groin area. They can also be caused by inflammation or infection of the epididymis (the coiled tube at the back of each testicle) or testicles^[4]. Secondary hydrocele usually occurs as a result of an underlying condition, such as infection, inflammation, or other health problems^[2].

In rare cases, hydroceles may occur with cancer of the testicle. This type of hydrocele can occur at any age but is most common in men older than 40^[7].

Who is affected by hydroceles?

Hydroceles are much more common in babies and infants, but may also occur in adolescents and adults^[8]. About 10% of newborn infants have a hydrocele, which often clears up without treatment within the first year^[8]. Hydroceles are particularly common in premature infants^[5].

Hydroceles occur in only about 1% of adults^[8]. They often disappear on their own without treatment^[8].

Symptoms of hydrocele

Often a hydrocele does not cause symptoms. The main symptom of a hydrocele is swelling on one or both sides of the scrotum that may feel like a water balloon^[8]. Often the only sign is a painless swelling of one or both testicles^[1]. The swelling might make an adult’s scrotum feel heavy^[1].

When symptoms are present, they can include^[4][8]:

• Pain, swelling, or redness of the scrotum
• A feeling of pressure at the base of the penis
• Swelling that changes in size during the day
• Discomfort in the groin area when sitting
• A feeling of heaviness in the scrotum

In general, pain gets worse as the swelling increases^[1]. Sometimes, the swollen area might be smaller in the morning and larger later in the day^[1].

Hydroceles are not harmful to the testicles in any way and they do not cause pain in most cases^[5]. Hydroceles usually do not cause infertility^[8].

How is a hydrocele diagnosed?

A hydrocele is usually diagnosed by an exam of the scrotum, which may appear enlarged^[4]. A health care provider should start with a physical exam. It is likely to include checking for pain in an enlarged scrotum, pressing on the stomach area and scrotum to check for inguinal hernia (a condition where part of the intestine pushes through a weak spot in the abdominal muscles), and shining a light through the scrotum^[9].

As part of the exam, the doctor will shine a light behind each testicle. This is called transillumination^[4]. This is to check for solid masses that may be caused by other problems, such as cancer of the testicle. Hydroceles are filled with fluid, so light will shine through them. Light will not pass through solid masses that may be caused by other problems^[4].

After the physical exam, additional tests may be needed^[9]:

• Blood and urine tests to help find out if there is an infection
• An imaging test called ultrasound to check for a hernia, a tumor or other causes of swelling in the scrotum

An ultrasound may be used to confirm the diagnosis of a hydrocele^[4].

Treatment options

Hydroceles are not usually dangerous and are treated only when they cause pain or embarrassment or when they decrease the blood supply to the penis, which is rare^[7]. Treatment is not usually needed if a hydrocele does not change in size or gets smaller as the body reabsorbs the fluid^[7].

In babies, a hydrocele sometimes goes away on its own^[9]. A baby’s hydrocele often goes away without treatment by age 1^[1]. Hydroceles in men younger than 65 may go away by themselves. But hydroceles in older men do not usually go away^[7].

At any age, it is important for a health care provider to check a hydrocele. That is because it can be linked to a problem with the testicles^[9]. It is important to see a health care provider if the scrotum looks swollen^[1].

A hydrocele that does not go away on its own might need to be removed with surgery^[9]. The surgery to remove a hydrocele is called a hydrocelectomy^[15]. Some people do not have to stay at the hospital overnight after surgery^[9].

Before the operation to remove a hydrocele, the patient receives medicine that keeps them from feeling pain. One type of medicine puts the patient in a sleep-like state, too^[9]. To remove the hydrocele, a surgeon makes a cut in the scrotum or lower stomach area^[9]. The doctor made a very small cut in the scrotum to drain the fluid from the hydrocele and to remove the fluid-filled sac^[15].

Sometimes, a hydrocele is found during surgery to repair an inguinal hernia. In this case, the surgeon might remove the hydrocele even if it is causing no discomfort^[9].

Fluid can also be removed from a hydrocele with a needle. This procedure is called aspiration^[7]. However, hydroceles that are aspirated often return, and surgery may then be needed^[7]. Aspiration is recommended only for men who are not physically able to have surgery because of the risk of infection and recurrence^[7].

Recovery after surgery

After surgery, the patient may feel more tired than usual and have some mild groin pain for several days^[15]. The groin and scrotum may be swollen or bruised. This usually gets better in 2 to 3 weeks^[15].

After surgery, patients might need a tube to drain fluid and a bulky bandage for a few days^[9]. The patient will probably be able to go back to work or school 4 to 7 days after surgery. But they will need to avoid strenuous exercise or heavy lifting for 2 to 4 weeks^[15].

Patients may need a follow-up exam because a hydrocele might come back^[9].