MRI helps avoid needless surgery in men with suspicion of penile fracture
In the diagnosis of penile fracture, magnetic resonance imaging (MRI) of the penis shows high sensitivity and negative predictive value for tunical rupture and concomitant urethral lesions, reports a study. This signifies its validity in the emergency setting if the goal is to treat all men who require intervention.
“Therefore, it could help avoid unnecessary surgery by excluding the diagnosis,” the investigators said. “However, solitary MRI is not sufficient for diagnosis and it should not replace clinical assessment or delay surgical exploration.”
Forty-three patients presented with suspicion of penile fracture between January 2006 and December 2016. Of these, 28 underwent MRI prior to surgical treatment in the emergency setting. Surgery was performed in all patients through a subcoronal, circumferential degloving approach.
The investigators estimated sensitivity, specificity, and positive and negative predictive values, as well as likelihood ratios of the positive and negative results of the agreement between MRI and intraoperative findings.
Nineteen of 28 patients (67.9 percent) had a confirmed intraoperatively penile fracture, while five of 28 (17.9 percent) had a concomitant urethral lesion.
MRI findings showed a robust association with intraoperative findings of tunical rupture, having 100-percent sensitivity (95 percent CI, 98.5–100), 77.8-percent specificity (50.6–100), 90.5-percent positive predictive value (78–100), 100-percent negative predictive value (97.6–100) and a positive result likelihood ratio of 4.5.
On the other hand, the accuracy of MRI was lower for urethral lesions with 60-percent sensitivity (17.1–100), 78.3-percent specificity (61.5–95.1), 37.5-percent positive predictive value (4–71), 90-percent negative predictive value (76.9–100) and a positive result likelihood ratio of 2.76.