What ultrasound is recommended for a 65-year-old male with bilateral scrotal pain and penile secretions?

Ultrasound Recommendations for 65-Year-Old Male with Bilateral Scrotal Pain

For a 65-year-old male presenting with bilateral scrotal pain and scrotal tenderness without swelling or penile secretions, a US duplex Doppler of the scrotum is the most appropriate initial imaging study. 1

Rationale for Duplex Doppler Ultrasound

• Standard ultrasound of the scrotum should include both grayscale and Doppler examination of the bilateral scrotal and inguinal areas 1
• Duplex Doppler involves acquisition and display of color Doppler and spectral Doppler waveforms in conjunction with grayscale sonographic imaging 1
• Ultrasound is the imaging modality of choice for scrotal evaluation due to its high resolution, Doppler capabilities, availability, and lack of ionizing radiation 2

Key Components of the Ultrasound Examination

• Grayscale imaging: While less sensitive for torsion, grayscale imaging helps identify other diagnoses such as inflammation due to epididymitis or solid/cystic scrotal masses 1
• Color Doppler assessment: Essential for evaluating testicular perfusion with reported sensitivity of 96-100% and specificity of 84-95% for detecting torsion 1
• Power Doppler: Can be used as an adjunct to color Doppler, as it is more sensitive for evaluating areas of slow flow 1

Clinical Considerations for a 65-Year-Old Male

• Epididymitis is overwhelmingly the most common etiology for acute scrotal pain in patients >25 years of age 1
• Testicular torsion is rare in patients >35 years of age, making it an unlikely diagnosis in a 65-year-old 1
• In adults, epididymo-orchitis typically presents with scrotal pain, and ultrasound will show an enlarged epididymis with increased flow on color Doppler 1

Ultrasound Findings in Common Conditions

• Epididymitis/Epididymo-orchitis: The most likely diagnosis in this age group, characterized by:

  • Enlarged epididymis with increased flow on color Doppler 1
  • Variable echogenicity (increased or decreased) 1
  • Scrotal wall thickening and hydrocele are common 1
  • Up to 20% concomitant rate for orchitis in patients with epididymitis 1

• Segmental testicular infarction: An uncommon cause of scrotal pain in adult men (median age 37-38 years):

  • Typically appears as a wedge-shaped avascular focal area on ultrasound 1
  • If ultrasound is equivocal, MRI can be helpful for further evaluation 1

Pitfalls and Caveats

• Ensure both testes are thoroughly examined, as bilateral pathology may be present 3
• A 12-17 MHz high-frequency linear array transducer should be used to provide excellent anatomic detail of the testicles and surrounding structures 3
• In rare cases where ultrasound findings are equivocal, additional imaging such as MRI may be considered, though this is uncommon 1
• Radionuclide imaging has been essentially replaced by Doppler ultrasound as the primary imaging modality for evaluation of acute scrotum 1

Summary

For a 65-year-old male with bilateral scrotal pain and tenderness without swelling, a comprehensive US duplex Doppler examination of the scrotum is the appropriate initial imaging study, as recommended by the American College of Radiology Appropriateness Criteria 1. This will allow for accurate diagnosis of the most likely etiologies in this age group, particularly epididymo-orchitis, while excluding other less common but important conditions.