By: Casey Wilson , MD

On behalf of the Ultrasound FAST

• Keep patient supine and comfortable (analgesia is key!)
• Place towel underneath scrotum to immobilize and elevate
• Use high frequency (6-14 MHz) linear probe
• Generous amount of warmed (if possible) gel to prevent cremasteric reflex
• Start with unaffected side
• Obtain transverse and longitudinal views
• Normal appearance seen in Figure 1

http://www.ultrasound-images.com

• Have a homogenous echogenicity (~ liver)
• Wall thickness 2-8 mm
• Normal size ~ 5 x 3 x 2 cm
• Obtain the “Spectacle View”  – seen in Figure 2

http://www.ultrasound-images.com

• Key to diagnosis is a difference in flow
• Apply color flow when you obtain the “spectacle view”
• Takes at least four hours to appear hypo-echoic and edematous
• When you see a flow differential, it’s important to keep in mind which side is hurting!  If the affected side has decreased flow, think torsion.  If the affected side has increased flow, think epididymitis.
• If the patient’s right testes is painful in the image below (Figure 3), you better be calling urology!

http://www.ultrasound-images.com

• Color Duplex Doppler is 96-100% sensitive and 84-95% specific for diagnosing testicular torsion.  
• A negative ultrasound is highly predictive of the ABSENCE of torsion at the time of exam.  
• Place the probe transversely at the mediastinum testis to assess vascular integrity
• The image below (Figure 4) demonstrates normal arterial flow.

http://www.sonosite.com/clinical-media

1. Adhikari, S.  Small Parts: Testicular Ultrasound.  www.Sonoguide.com
2. Blaivas M, Sierzenski P, Lambert M. Emergency evaluation of patients presenting with acute scrotum using bedside ultrasonography. Acad Emerg Med. 2001; 8(1):90-3. 
3. Cassar S, Bhatt S, Paltiel H, et al. Role of spectral Doppler sonography in the evaluation of partial testicular torsion. J Ultrasound Med. 2008;27(11):1629-38