Description

A varicocele is an abnormal tortuosity and dilation of the testicular veins and the pampiniform venous plexus of the spermatic cord.

Epidemiology

• Rare in prepubertal boys, increases with age to approximately 15% in late adolescence and healthy adult population
  • 2 to 10 years old, <1%
  • 11 to 14 years old, 7.8%
  • 15 to 19 years old, 14.1%
• Based on World Health Organization observational study (1992), 15–20% of adult varicocele patients have fertility problems.
  • Varicocele presents in 25% of men with abnormal semen analysis and 12% of men with normal semen parameters.
  • Present in 35–40% of males with primary infertility
• Left-sided predominance, 90%
• No racial predilection

Risk Factors

• Exact mechanisms have not been fully elucidated.
• May be related to physiologic changes in puberty, such as rapid testicular growth and increased testicular blood flow
• Associated with increased height and low body mass index
• Increased risk in 1st-degree relatives of patients with a varicocele

Pathophysiology

• Association between varicocele and testicular dysfunction/fertility compromise
  • Impaired spermatogenesis: decreased motility, decreased density, and increased number of pathologic sperm forms; decreased total sperm count
• Ipsilateral testicular hypotrophy
  • Recent data demonstrates correlation between varicocele grade and testicular hypotrophy although not observed in prior studies.
  • Testicular “catch-up growth” can be seen after varicocelectomy.
  • Catch-up growth can all be seen in 30–50% of patients managed conservatively.
• Potentially caused by an embryonic field defect, affecting growth of bilateral testicles
• Exact mechanisms not clearly elucidated—multiple theories:
  • Hyperthermia: Varicocele increases intratesticular temperature, likely by interfering with the pampiniform plexus’ ability to provide countercurrent cooling system.
  • Potential reflux of renal and adrenal metabolites, potentially causing testicular damage
  • Increased production of nitric oxide and reactive oxygen species correlate with severity of varicocele.
  • Endocrine abnormalities are found in subset of patients with varicocele, including low testosterone, abnormal response to gonadotropin-releasing hormone (GnRH), and impaired Leydig cell function.

Etiology

Associated with anatomy of left testicular vein

• Inserts into renal vein at right angle (right testicular vein drains into vena cava)
• Incompetent or absent valves
• Left testicular vein 8 to 10 cm longer than right, with increased pressure
• Increased venous pressure from “nutcracker phenomenon”: compression of left renal vein as it passes between aorta and superior mesenteric artery