Purpose: Despite the high sensitivity and specificity of scrotal ultrasonography, there continue to be reports of missed torsion. These "false-negative" scans are attributed to technical factors and intermittent torsions. We hypothesize that patients with specific anatomical configurations maintain testicular blood flow for prolonged periods, and, therefore, will have flow on ultrasound despite concurrent torsion.
Materials and methods: Patient charts and scrotal ultrasounds were reviewed to identify patients younger than 18 years who underwent scrotal exploration between January 1998 and January 2003 for acute scrotum. Patients who underwent radiological evaluation before scrotal exploration were the main focus of this study. Operative reports were reviewed for specific anatomical details.
Results: A total of 61 patients underwent scrotal exploration for acute scrotum during the study period. Of these patients 14 had torsion confirmed intraoperatively and a preoperative scrotal ultrasound available. Four of these 14 patients had normal testicular blood flow on ultrasound but had testicular torsion confirmed intraoperatively. Operative findings suggest that these patients have specific anatomical characteristics.
Conclusions: Testis perfusion can be maintained for a prolonged period in the presence of testicular torsion. Anatomical variability may account for differences in the duration of viability of the torsed testis. A high index of suspicion must be maintained to avoid missing the diagnosis of testicular torsion in these challenging cases.