Impact of repeated testicular fine needle aspirations (TEFNA) and testicular sperm extraction (TESE) on the microscopic morphology of the testis: An animal model

Abstract

Background: The aim of this work was to compare testicular histological changes occurring following testicular fine needle aspiration (TEFNA) and testicular sperm extraction (TESE). Methods: TESE or TEFNA were performed on normal male rats, in a similar manner to azoospermic men. The animals were killed after 7, 14 and 31 days and their testes were examined. Results: TESE caused chronic inflammation, occasional necrosis and degenerative changes in testicular germ cells in only ∼10% of the remaining testicular tissue. TEFNA caused widespread architectural distortion of seminiferous tubules into irregular and deformed lumens lined by Sertoli cells only, as well as focal chronic inflammation, necrosis and degenerative changes accompanied by decreased spermatogenesis. Similar but less extensive changes were noted when fewer punctures were performed. When negative suction pressure was not applied during TEFNA, similar histological changes occurred, indicating that testicular damage was related to the puncture itself. Following either procedure, the contralateral non-operated testes were unaffected. Conclusion: In this animal model, TEFNA inflicts severe, progressive and irreversible damage on the architecture of the tubules in the needle's path. The multi-focal nature of this technique eventually leads to widespread tubular atrophy that is proportional to its extent. In contrast, TESE causes localized scarring and fibrosis, rendering most of the remaining testicle intact. The clinical relevance of such findings, produced in normal animal testes, to testes of azoospermic men, is yet to be determined.