What is the difference in diagnosis and treatment between perinatal (around birth) and prenatal (before birth) testicular torsion?

Differentiating Perinatal vs Prenatal Testicular Torsion

Perinatal testicular torsion occurs around birth (first month of life), while prenatal testicular torsion occurs before birth and is already present at delivery, both with distinct diagnostic features and management approaches. 1, 2

Timing and Definition

• Perinatal testicular torsion is defined as torsion occurring around birth or in the first month after birth, accounting for approximately 10% of all testicular torsion cases in children 1, 3
• Prenatal testicular torsion occurs during intrauterine development and is already present at the time of birth, representing a subset of perinatal torsion cases 4, 2

Pathophysiology

• Both perinatal and prenatal testicular torsion are predominantly extravaginal in nature (occurring outside the tunica vaginalis) 1, 5
• Extravaginal torsion involves twisting of the entire spermatic cord along with its coverings, unlike the intravaginal torsion more commonly seen in older children and adults 2, 5

Clinical Presentation

• Prenatal testicular torsion is typically discovered at birth with a hard, non-tender, discolored testicle that may have already undergone necrosis 4, 5
• Perinatal torsion (occurring after birth) may present with acute scrotal swelling, discoloration, and occasionally pain, though neonates may not exhibit typical pain behaviors 2, 3
• Prenatal torsion is often asymptomatic at presentation as the acute event occurred in utero, while perinatal torsion occurring after birth may present with acute symptoms 2

Diagnostic Approach

• Physical examination findings differ:

  • Prenatal torsion: Firm, non-tender testicle with scrotal discoloration and no acute inflammation 4, 5
  • Perinatal torsion (post-birth): Acute scrotal swelling, tenderness, and inflammation may be present 2

• Ultrasound is the primary diagnostic tool for both conditions 6, 7:

  • Grayscale ultrasound findings:

    • Prenatal torsion: Heterogeneous echotexture, often with calcifications or cystic areas indicating long-standing ischemia 5
    • Perinatal torsion: May show enlarged, hypoechoic or heterogeneous testicle with the "whirlpool sign" of the twisted spermatic cord 7, 3

  • Doppler assessment:

    • Both conditions typically show absent blood flow to the affected testicle 7, 3
    • In prenatal torsion, absent flow has been present for longer, often with more advanced tissue changes 5

• Ultrasound elastography can be particularly useful in assessing the hardened structure of the necrotic testicle in prenatal torsion 5

Management Considerations

• Salvage rates differ significantly:

  • Prenatal torsion: Salvage is virtually impossible (less than 1%) as the torsion occurred in utero with prolonged ischemia 4
  • Perinatal torsion (post-birth): If diagnosed and treated within 6-8 hours of symptom onset, salvage may be possible 7

• Surgical approach:

  • For prenatal torsion: Controversy exists regarding management, with options including orchiectomy of the affected testicle and prophylactic contralateral orchiopexy 4
  • For perinatal torsion occurring after birth: Immediate surgical exploration is recommended to attempt testicular salvage 1, 7

• In both cases, assessment of the contralateral testicle is critical due to the risk of bilateral involvement, which can be difficult to detect clinically or by imaging 8, 4

Key Diagnostic Pitfalls

• Prenatal torsion may be misdiagnosed as other causes of scrotal swelling in neonates, including hydrocele, hematoma, or tumor 3, 5
• The absence of acute symptoms in prenatal torsion may lead to delayed diagnosis and management 2
• Physical examination alone may be insufficient to differentiate between prenatal and perinatal torsion, making imaging crucial 3, 5
• The risk of asynchronous bilateral torsion must be considered in both conditions, as it can lead to anorchia, infertility, and endocrine deficiencies 8, 4