From the Guidelines
Ultrasound is the primary imaging modality used for evaluating testicular pain, and it should be performed as the initial imaging for the acute onset of scrotal pain without trauma or antecedent mass in an adult or child. When a patient presents with testicular pain, a scrotal ultrasound with color Doppler should be performed as it provides excellent visualization of testicular structures without radiation exposure 1. This non-invasive test can quickly identify common causes of testicular pain including testicular torsion (a urologic emergency requiring immediate surgery), epididymitis, orchitis, hydrocele, varicocele, testicular trauma, or testicular masses.
Key Points to Consider
- Ultrasound is particularly valuable because it can differentiate between conditions requiring urgent surgical intervention (like torsion) versus those that can be managed medically (like epididymitis) 1.
- The high-frequency sound waves used in ultrasound provide detailed images of soft tissue structures, while the Doppler component allows assessment of blood flow, which is crucial in diagnosing conditions like torsion where blood flow is compromised.
- In cases where ultrasound findings are inconclusive or if there's suspicion of metastatic disease, MRI may be used as a secondary imaging option, though this is less common in the acute setting 1.
- CT scans are rarely used for primary testicular imaging but may be employed if there's concern about extension of pathology into the abdomen or pelvis.
Diagnostic Approach
- The use of a combination of dynamic contrast-enhanced T1-weighted MRI with T2-weighted and T2*-weighted sequences may help distinguish patients with torsion alone from those with torsion and hemorrhagic necrosis, but this is not the first line of imaging 1.
- Diffusion restriction and apparent diffusion coefficient (ADC) may be useful to differentiate testicular torsion from other scrotal disorders, but ultrasound remains the primary modality for initial evaluation 1.
Clinical Considerations
- The contralateral asymptomatic testicle should be used as an internal control during ultrasound evaluation 1.
- Clinical correlation with the presence of fever, waxing and waning pain, and laboratory markers for infection must be integrated in the clinical assessment to distinguish between testicular torsion and epididymoorchitis 1.
From the Research
Imaging for Testicular Pain
- The most commonly used imaging modalities for testicular pain are:
- Doppler ultrasound is considered the most helpful in confirming the diagnosis of testicular torsion 2, 3, 4, 5
- The sensitivity, specificity, positive predictive value, and negative predictive value of colour Doppler ultrasound in predicting testicular torsion are 96.9%, 88.9%, 96.9%, and 89%, respectively 5
Specific Conditions
- For testicular torsion, Doppler ultrasound and radionuclide testicular scintigraphy can be used to confirm the diagnosis 2, 4
- For epididymitis, high-transducer sonography can be used to visualize the epididymis and its detailed anatomy 6
- For acute scrotal pain, colour Doppler ultrasound can be used to predict testicular torsion 5
Clinical Application
- Imaging modalities can help differentiate between testicular torsion and other conditions such as epididymitis, strangulated inguinal hernia, traumatic hematoma, testicular tumor, or testicular fracture 2, 3, 4
- Prompt surgical treatment is indicated for testicular torsion, and imaging modalities can help guide medical or surgical treatment 3, 4, 5