Hydrocele

Description

A hydrocele is the accumulation of fluids around the testicle, within the tunica vaginalis or processus vaginalis.

• Communicating hydrocele: fluid passing from peritoneal cavity into patent processus vaginalis
• Noncommunicating hydrocele: fluid confined within the processus vaginalis (hydrocele of the cord) or tunica vaginalis
• Abdominal-scrotal hydrocele: fluid collection within processus vaginalis, extending into retroperitoneum
• Reactive hydrocele (noncommunicating): accumulation of fluid within tunica vaginalis caused by infection, trauma, or other inflammatory conditions

Epidemiology

• 2–5% of male neonates have hydrocele.
• Male more common than female
  • Female: “cyst” or “hydrocele” in the canal of Nuck; may be communicating or noncommunicating
• Right more common than left
• Majority asymptomatic
• Simple (noncommunicating): commonly seen at birth, frequently bilateral, may be large
  • Majority spontaneously resolve in 12 to 24 months.
• Persistent hydroceles beyond 24 months and those presenting after birth more likely to be communicating
• Age >12 years old: majority noncommunicating
• Adolescent/adult hydroceles are generally acquired (reactive) and idiopathic in origin.

Risk Factors

• Similar to inguinal hernia
• Prematurity, low birth weight, gestational progestin use, connective tissue anomalies, cystic fibrosis, cryptorchidism, posterior urethral valves, and other syndromic disorders
• Trauma or infection
• Lymphatic obstruction (i.e., varicocelectomy, filariasis, pelvic radiation, malignancy)

Pathophysiology

• Communicating hydrocele can become indirect inguinal hernia, with potential for incarceration.
• Noncommunicating hydrocele generally thought to be low clinical concern.
• Potential damage in large, tense hydroceles
  • Raised intrascrotal temperature can cause potential testicular harm.
  • Tense hydrocele may cause pressure atrophy.
  • Increased resistive index observed in subcapsular artery and absent testicular diastolic flow indicate risk for permanent damage.

Etiology

• Communicating hydrocele similar to indirect inguinal hernia (defined by contents entering through patent processus vaginalis: peritoneal fluid versus fat or visceral organ)
• In testicular descent, lip of peritoneum descends with testicle, the processus vaginalis, and covers testicle, tunica vaginalis.
• Patent processus in girls (canal of Nuck) related to descent of round ligament to labia, female equivalent of gubernaculum
• Related to delayed closure of processus vaginalis
  • Complete closure on both side in 18% of newborns
  • 40% close in first 2 months of life
  • 60% close by 2 years
  • Patent processus vaginalis commonly associated with undescended testicles
  • Adult autopsy data demonstrate 15–30% patent.
• Reactive (acquired) hydrocele is imbalance between fluid production and absorption.
  • Majority are idiopathic.
    • Defective lymphatic drainage
    • Aspirated fluid similar protein content to lymphatic fluid
  • Result of inflammation from trauma, testicular torsion, torsion of testicular appendage, epididymo-orchitis
  • Postvaricocelectomy second most common cause