Taqaandan is said to be painless and has been compared to cracking ones knuckles, but the practice of taqaandan has led to an increase in the prevalence of penile fractures in western Iran. Taqaandan may be performed to achieve detumescence. Diagnosis
Imaging studies
Ultrasound examination is able to depict the tunica albuginea tear in the majority of cases (as a hypoechoic discontinuity in the normally echogenic tunica). In a study on 25 patients, Zare Mehrjardi et al. concluded that ultrasound is unable to find the tear just when it is located at the penile base. In their study magnetic resonance imaging (MRI) accurately diagnosed all of the tears (as a discontinuity in the normally low signal tunica on both T1- and T2-weighted sequences). They concluded that ultrasound should be considered as the initial imaging method, and MRI can be helpful in cases that ultrasound does not depict any tear but clinical suspicions for fracture are still high. In the same study, authors investigated accuracy of ultrasound and MRI for determining the tear location (mapping of fracture) in order to perform a tailored surgical repair. MRI was more accurate than ultrasound for this purpose, but ultrasound mapping was well correlated with surgical results in cases where the tear was clearly visualized on ultrasound exam. The advantage of ultrasound in the diagnosis of penile fracture is unrivaled when its noninvasive, cost-effective, and nonionising nature are considered.Penile trauma can result from a blunt or penetrating injury, the latter being rarely investigated by imaging methods, almost always requiring immediate surgical exploration.
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