Scrotal wall pertechnetate washout as a predictor of testicular salvage for missed torsion by testicular scintigraphy

Background and objective: Testicular torsion (TT) is a urological emergency; early diagnosis and intervention prevent long-term complications, including male infertility. In our case series, we aimed to distinguish if the washout of tracer from the scrotum could be predictive of salvageability of the testes in patients with testicular scintigraphy (TS), which is diagnostic of testicular torsion. Methods: We evaluated the TS scans of patients who underwent surgical intervention for orchidectomy for suspected missed TT from January 2016 to December 2021 at Dr George Mukhari Academic Hospital. We assessed the washout of tracer in the scrotum between 5-min and 20-min images and determined the correlation with salvageability of the testes in patients scintigraphically diagnosed with missed TT. Semiquantitative (maximum and minimum counts) and visual analysis were conducted. Results: A total of 12 patients underwent surgery. Of these, 50% of the testes were salvaged and in 50%, the testes could not be salvaged and complete orchidectomy was performed. On visual and semiquantitative analysis, we detected a progressive decrease in pertechnetate uptake in the scrotal wall uptake in the salvaged testes. The maximum percentage of decrease in counts in this group was 34%; the median time to presentation after the onset of symptoms was 2.5 days with an interquartile range of 2 days and a range of 1 day to 5 days. In the non-salvaged group, visual and semiquantitative increase in uptake in scrotal wall was observed. The maximum percentage increase in counts was 32%. The median time to presentation after the onset of symptoms in these patients was 6 days with an interquartile range of 5 days and a range of 2 days to 14 days. Conclusion: This case series demonstrates an association between pertechnetate washout and salvageability of the testes. Testicular salvage is observed in patients who demonstrated a progressive decrease in uptake of pertechnetate in the scrotal wall over a 20 min imaging time and in patients who presented beyond the golden 6 h time limit. Testicular scintigraphy may be a great tool in identifying those patients with higher possibility of salvage and assist to prioritise their surgery. (authors)