Purpose: We evaluated the role of magnetic resonance imaging of the penis in the diagnosis of penile fracture and/or concomitant urethral lesions in real-life emergency settings compared with intraoperative findings.
Materials and methods: A total of 43 patients presented with suspicion of penile fracture between January 2006 and December 2016. Magnetic resonance imaging was performed in 28 patients prior to surgical treatment in the emergency setting. Surgery was done in all patients via a subcoronal, circumferential degloving approach. We calculated sensitivity, specificity, and positive and negative predictive values as well as likelihood ratios of the positive and negative results of the agreement between magnetic resonance imaging and intraoperative findings.
Results: Intraoperatively penile fracture was confirmed in 19 of 28 patients (67.9%) and a concomitant urethral lesion was observed in 5 of 28 (17.9%). Magnetic resonance imaging findings were highly associated with intraoperative findings of tunical rupture, including 100% sensitivity (95% CI 98.5-100), 77.8% specificity (95% CI 50.6-100), 90.5% positive predictive value (95% CI 78-100), 100% negative predictive value (95% CI 97.6-100) and a positive result likelihood ratio of 4.5. Magnetic resonance imaging had lower accuracy for urethral lesions with 60% sensitivity (95% CI 17.1-100), 78.3% specificity (95% CI 61.5-95.1), 37.5% positive predictive value (95% CI 4-71), 90% negative predictive value (95% CI 76.9-100) and a positive result likelihood ratio of 2.76.
Conclusions: Magnetic resonance imaging may be applicable in the emergency setting if the goal is to treat all men who warrant intervention. It has high sensitivity and negative predictive value for tunical rupture and concomitant urethral lesions. Therefore, it could help avoid unnecessary surgery by excluding the diagnosis. However, solitary magnetic resonance imaging is not sufficient for diagnosis and it should not replace clinical assessment or delay surgical exploration.
Keywords: crush syndrome; emergency medicine; magnetic resonance imaging; penis; urethra.