Glowing Dye Helps Surgeons Save Ruptured Testes in Children

When a child’s testicle ruptures, surgeons face a race against time and a painful dilemma: how much damaged tissue should be removed? Cut too little, and dead tissue may cause infection, atrophy, or loss of the organ. Cut too much, and viable tissue that could have recovered is sacrificed forever. A new pilot study from the Children’s Hospital of Soochow University in Suzhou, China, suggests that a glowing green dye already familiar to surgeons in other fields may help resolve that dilemma in real time, offering the first detailed look at how near-infrared fluorescence imaging could guide emergency testicular repair in children.

The technique relies on indocyanine green, or ICG, a fluorescent tracer that has been approved for clinical use for decades. When injected into a vein, ICG binds to plasma proteins and stays within the bloodstream. Illuminated by near-infrared light, it emits a fluorescent signal that can be captured by a specialized camera system, allowing surgeons to watch blood perfusion unfold across the surface of an organ in real time. Because near-infrared light penetrates tissue more deeply than visible light and generates little background interference, the resulting images can reveal the boundary between tissue that is being fed by blood and tissue that has lost its supply.

In the study, published in BMC Pediatrics, a surgical team led by Li Tao, Xu Cao, and corresponding author Shu Dai applied this technology to ten children who underwent emergency surgery for testicular rupture between July 2023 and December 2025. During each operation, the surgeons injected ICG intravenously at a dose of 0.2 milligrams per kilogram of body weight and then used a near-infrared fluorescence imaging system to perform real-time angiography of the exposed testicle. The goal was to delineate, on the operating table and within minutes, the exact boundary between nonperfused tissue and tissue that was still receiving blood.

The results were strikingly consistent. In all ten patients, the fluorescence imaging clearly delineated the boundary between areas where fluorescence could be detected and areas where it could not. Those findings were incorporated into the surgeons’ overall intraoperative assessment and used to guide selective excision of tissue considered nonviable. Once the dead tissue had been removed, the team repaired the resulting defect using either sutures of the tunica albuginea, the tough fibrous capsule surrounding the testicle, or a patch of tunica vaginalis, the membrane that normally cushions the organ within the scrotum.

Follow-up examinations offered cautious encouragement. With a median follow-up of ten months, ranging from three to 32 months, all of the repaired testes showed regular morphology and homogeneous echogenicity on grayscale ultrasound, an indication that the tissue architecture had healed without the scarring or irregularity that often follows significant testicular injury. Color Doppler flow imaging, the standard ultrasound technique for visualizing blood flow, demonstrated normal blood flow signals in every case. No postoperative complications were documented in the available clinical records during the follow-up period.

The clinical stakes of this problem are considerable. Testicular rupture, in which blunt trauma tears the tunica albuginea and extrudes the delicate seminiferous tubules inside, is one of the most time-sensitive emergencies in pediatric urology. The viability of the gonad depends heavily on how quickly blood flow is restored and how accurately the surgeon judges which tissue can survive. Traditional assessment relies on visual inspection of color, texture, and bleeding at the cut edges, supplemented by preoperative ultrasound. These cues are notoriously subjective, and both errors carry lasting consequences: leaving devitalized tissue increases the risk of necrosis and atrophy, while over-resection removes germ cells that might otherwise have contributed to preserved fertility and hormone production.

ICG fluorescence imaging addresses that subjectivity directly by giving surgeons an objective, dynamic map of perfusion. The physics behind the technique is elegant. ICG absorbs light in the near-infrared range, around 800 nanometers, and re-emits it at slightly longer wavelengths. Because hemoglobin and water absorb relatively little light in this window, the fluorescence signal can be detected from tissue several millimeters to a centimeter beneath the surface, and the contrast between perfused and nonperfused regions appears within seconds of injection. In other surgical specialties, from colorectal anastomosis to reconstructive flap surgery, this real-time perfusion mapping has already changed intraoperative decision-making, and the Suzhou team’s work extends that logic to a delicate pediatric organ where every cubic millimeter of viable tissue matters.

The authors are careful to frame their findings as preliminary. This was a pilot feasibility study with only ten patients, conducted as a retrospective review of children who had already been treated under an approved new clinical technology application. The ethical approvals covered both the clinical use of ICG during testicular rupture surgery, granted in 2023, and the retrospective analysis of the resulting records, approved under number 2026CS087 before any data were abstracted. Because the study lacked a control group, it cannot yet demonstrate that ICG guidance improves long-term outcomes compared with conventional surgical judgment alone. The uniformly good results could reflect the imaging technique, careful patient selection, skilled surgery, or simply the natural history of promptly treated rupture. The authors explicitly state that their findings require validation in larger, controlled studies to determine the technique’s impact on long-term outcomes.

Nevertheless, the safety profile observed in this small cohort is reassuring. ICG has a long track record of clinical use, with adverse reactions generally rare and mild, and no adverse events were observed in these ten children. The dose used, 0.2 milligrams per kilogram, is modest, and the imaging procedure adds only a few minutes to an emergency operation, a meaningful consideration when ischemia time is a critical determinant of organ survival. For pediatric urologists, the appeal of the technique lies precisely in this combination of speed, simplicity, and visual clarity: a single injection and a camera turn an invisible physiological variable, blood flow, into an immediately interpretable image on the operating room monitor.

The broader significance of the study extends beyond urology. It represents part of a growing movement in surgery toward fluorescence-guided decision-making, in which molecular tracers and optical imaging replace guesswork with measurable signals. If larger trials confirm the Suzhou results, ICG imaging could become a standard adjunct in pediatric scrotal trauma, helping surgeons preserve organs that would once have been lost. For the children in this study, the glowing green map on the operating room monitor appears to have done exactly what such technology promises: it showed the surgeons where life remained in damaged tissue, and it helped them keep it. Whether that promise holds across hundreds of patients will be the question that future controlled studies must answer, but the first step has now been taken, and it was taken in glowing green.

Subject of Research: Intraoperative indocyanine green fluorescence imaging to assess tissue perfusion during pediatric testicular rupture surgery

Article Title: Indocyanine green fluorescence imaging for intraoperative assessment of tissue perfusion in pediatric testicular rupture: a pilot feasibility study

Article References: Tao, L., Cao, X., Huang, M., Wang, T., Zhang, L., Xia, H., Fu, M., Zhou, Y., Zhang, T., Yan, X., & Dai, S. (2026). Indocyanine green fluorescence imaging for intraoperative assessment of tissue perfusion in pediatric testicular rupture: a pilot feasibility study. BMC Pediatrics. https://doi.org/10.1186/s12887-026-07846-8

Image Credits: AI Generated

DOI: 10.1186/s12887-026-07846-8

Keywords: indocyanine green, fluorescence imaging, testicular rupture, pediatric surgery, tissue perfusion, near-infrared imaging, intraoperative assessment, urology, pilot study, organ preservation, surgical imaging, BMC Pediatrics