Spectroscopy of Testicular Tissues as a Tool for Azoospermia Visualization During Micro-TESE and IVF: a Feasibility Study

Abstract

Non-obstructive azoospermia observed in 10% of infertile men and 0,6% of all men is the most severe form of male infertility. The histological structure of testicular tissue in patients with non-obstructive azoospermia is heterogeneous and is represented by various disorders of spermatogenesis. The only way to achieve pregnancy in the families of patients with non-obstructive azoospermia is the method of in vitro fertilization with intracellular sperm injection. The most effective method of detecting spermatozoa suitable for in vitro fertilization in testicles is the micro-TESE method. It is based on a subjective visual assessment of tissues and allows detecting spermatozoa in non-obstructive azoospermia only in 38-60% of cases. To increase the effectiveness of micro-TESE, the method used must be objective, high-specific, safe for reproductive cells, and also implemented during the operation in real time. The existing approaches to solving the problem of identifying seminal tubules with preserved spermatogenesis, such as multiphoton microscope, Raman spectroscopy, optical coherence tomography and etc., are either associated with the use of laser radiation with unproven safety or cannot be implemented intraoperatively and operationally. The paper considers the possibility of creating a specialized microsurgical system for intraoperative evaluation of testicular tissues histological structure using the spatial distribution of its spectral characteristics. We proposed to implement such a system based on multispectral imaging of the studied tissues with real-time data processing and displaying the results using augmented reality methods. The reflectance spectrum of testicular tissue with varying degrees of preservation of spermatogenesis in the visible and near infrared spectral ranges was studied. Spectral regions were identified that potentially provide the best differentiation of healthy tissues and tissues with impaired spermatogenesis. The described approach can be implemented intraoperatively and safely and may serve to automate and objectify the diagnosis of testicular tissues in micro-TESE.