# A preliminary study on predicting the prognosis of testicular torsion based on indocyanine green-guided near-infrared fluorescence imaging

## TL;DR

This study explores using a special imaging technique during surgery to determine if a testicle is still viable and predict its recovery after torsion.

## Contribution

The study introduces a method using ICG-NIRF imaging to assess testicular viability and predict outcomes during testicular torsion surgery.

## Key findings

- Type A fluorescence patterns were associated with normal blood flow and minimal atrophy.
- Type B and C patterns showed severe atrophy and reduced or absent blood flow.
- ICG-NIRF imaging effectively predicted postoperative testicular outcomes.

## Abstract

Testicular viability is the primary basis for selecting the surgical approach during orchiopexy for testicular torsion (TT); however, there is currently a lack of methods that can objectively assess testicular viability intraoperatively. The purpose of this study is to evaluate testicular viability and predict postoperative testicular outcomes using indocyanine green-guided near-infrared fluorescence (ICG-NIRF) imaging during surgery for TT.

We retrospectively reviewed pediatric patients treated for TT at our hospital between January 2024 and December 2024. Intraoperative ICG-NIRF imaging was used to assess testicular viability. Cases were classified into three types based on the testicular fluorescence patterns: Type A (extensive parenchymal fluorescence), Type B (fluorescence limited to the tunica vasculosa), and Type C (no fluorescence). Follow-up ultrasounds were performed at 1, 3, and 6 months postoperatively to record testicular volume and blood flow, and to calculate the testicular atrophy index (TAI).

This study enrolled a total of 19 pediatric patients. The cases were distributed as follows: 8 cases of Type A, 8 cases of Type B, and 3 cases of Type C. At the 6-month postoperative follow-up, Type A testes all showed normal blood flow signals on ultrasound, seven cases exhibited no atrophy, and one case had mild atrophy, the TAI [median (P25, P75)] was 4.75% (−0.72, 9.34). Among the 8 Type B testes, ultrasound showed normal blood flow signals in 1 case, reduced blood flow in 5 cases, and absent blood flow in 2 cases. All cases experienced severe atrophy, with a TAI [median (P25, P75)] of 86.95% (83.83, 97.31). Among the 3 Type C testes, ultrasound revealed reduced blood flow signals in 1 case and absent blood flow signals in 2 cases. All cases demonstrated severe atrophy, with a TAI [median (P25, P75)] of 88.15% (86.65, 90.56). There was a statistically significant difference in the TAI on comparison of Type B and Type C with Type A, respectively (p = 0.003 and p = 0.030).

The application of ICG-NIRF imaging during surgical intervention for TT can effectively assess testicular viability and predict the prognosis of TT.