Background: Testicular torsion is an acute urological emergency occurring in children and adolescents. Accurate and fast
diagnosis is important as the resulting ischemia can destroy the testis. Currently, Doppler ultrasound is the preferred
diagnostic method. Ultrasound is not readily available in all centers which may delay surgical treatment.
In this study, a rat model was used to examine the feasibility and sensitivity of using spatially-resolved near infrared
spectroscopy (SR-NIRS) with a custom-made miniaturized optical sensor probe to detect and study changes in testicular
hemodynamics and oxygenation during three degrees of induced testicular torsion, and after detorsion.
Methods: Eight anesthetized rats (16 testes) were studied using SR-NIRS with the miniaturized optical probe applied
directly onto the surface of the surgically exposed testis during 360, 720 and 1080 degrees of torsion followed by detorsion.
Oxygenated, deoxygenated and total hemoglobin and TOI% were studied pre-and post-manipulations.
Results: NIRS monitoring reflected acute testicular ischemia and hypoxia on induction of torsion, and tissue reperfusionreoxygenation
after detorsion. Testicular torsion at 720 degrees induced the maximum observed degree of hypoxic
changes. In all cases, rhythmic changes were observed in the NIRS signals before inducing torsion; these disappeared after
applying 360 degrees of torsion and did not reappear after detorsion.
Conclusion: This animal study indicates that SR-NIRS monitoring of the testes using a directly applied miniature sensor
is a feasible and sensitive method to detect testicular ischemia and hypoxia immediately after torsion occurs, and testicular
reperfusion upon detorsion. This study offers the potential for a SR-NIRS system with a miniaturized sensor to be explored
further as a rapid, noninvasive, optical method for detecting testicular torsion in children.