Dx: Calcified Lesion
You obtain a transverse image of both testicles to compare the echo-texture, size, and appearance of each testis. On the inferior and posterior aspect of the right testicle, you note a heterogeneous mass. Zooming in on the mass, you note a central hyperechoic, calcified lesion surrounded by hypoechoic fluid and peripheral edema.
The edges of the mass are indistinct and the mass is tender during your scan. Given the patient’s recent antibiotics, it could be a drug-resistant abscess, but it could also be a malignant testicular mass. You stand by as your resident explains to the patient that he is going to need a comprehensive ultrasound through the radiology department for further characterization of the mass, and that the plan is to touch base with Urology to determine the best management options available. The patient thanks you both for your care and asks if he can post his ultrasound images on Facebook.
As you and your resident walk the ultrasound machine back to its storage area, you can’t help but marvel at the pathology you have diagnosed and treated today.
“When you hear hoof-beats, you don’t always have to think zebras,” you tell your resident, “but remember that zebras do exist.”
“Zebras?!” the resident responds, “ With the way things have been going lately, I’m going to be on the lookout for a freakin’ unicorn!”
Pearls & Pitfalls for Bedside Testicular Ultrasound
1. It is often very difficult to determine the etiology of a patient’s testicular pain based on history and physical exam alone. When signs and symptoms overlap between various diagnoses, use ultrasound to obtain additional data.
2. A testicular scan is best performed with a high frequency, linear array transducer (10-5 MHz).
3. Have the patient lie supine with their knees bent and hips externally rotated to fully expose their testicles and scrotum. Place a rolled towel underneath their scrotum to help elevate it for better visualization and access during the scan.
4. Begin by obtaining a transverse view of both testes by placing the transducer underneath the testicles with the midline of the transducer centered along the scrotal raphe. Direct the beams in a cranial direction toward the patient’s head.
5. Scan through the unaffected testis first and obtain transverse images along the inferior, mid, and superior planes. Next, obtain longitudinal views along the medial, central, and lateral planes.
6. When scanning the painful or enlarged testis, compare its size and echogenicity to the contralateral side. A normal testis should measure approximately 3 cm wide and 5 cm long.
7. Obtain views of the epididymal head, body, and tail along the superior-posterior-lateral aspect of each testis.
8. If a palpable abnormality is encountered during the scan, obtain dedicated views of that region.
9. To improve your view of the entire organ, have the patient perform a Valsalva maneuver or “bear down” during the scan. Using warm ultrasound gel will also minimize the amount of testicular and scrotal retraction encountered during the scan.
10. Once the size and echogenicity of each testis has been evaluated, apply spectral or color/power Doppler to evaluate flow in each testis. Start with an image of both testes side-by-side and assess for symmetry of Doppler flow. Utilize low-flow detection settings and optimize transducer frequency to maximize Doppler sensitivity, meanwhile maintaining adequate penetration.
11. If flow cannot be easily visualized on color Doppler, use power Doppler over the area of concern. Spectral Doppler can be used to help determine if you are visualizing arterial or venous flow.
12. Suspicious masses or lesions require a comprehensive ultrasound and timely urologic follow-up. This patient ended up being diagnosed with testicular cancer and treatment has been initiated as an outpatient.
Brady Pregerson manages a free on-line EM Ultrasound Image Library and is the editor of the Emergency Medicine Pocketbook series. For more information visit EMresource.ORG.
Teresa S. Wu is the Associate Residency Director, and Director of Ultrasound and Simulation Programs and Fellowships, for the Maricopa Emergency Medicine Program in Phoenix, Arizona.