Related Experiment Video
Updated: Feb 4, 2026
Vessel-Sparing Microsurgical Longitudinal Intussusception Vasoepididymostomy to Treat Epididymal Obstructive Azoospermia
Published on: May 27, 2022
The seminiferous tubule caliber pattern as evaluated at high magnification during microdissection testicular sperm
E Caroppo1, E M Colpi2, G Gazzano3
1Department of Maternal and Child Health, Reproductive and IVF Unit, Asl Bari, Conversano, Italy.
Background:
microTESE proved to be the gold standard surgical approach for patients with non-obstructive azoospermia (NOA), but sperm retrieval rates (SRRs) vary considerably among centers. Some authors compared their SRRs with the pattern of seminiferous tubule caliber found at high magnification, but none provided diagnostic accuracy measures.
Objective:
The present retrospective study sought to verify the diagnostic accuracy of the pattern of seminiferous tubule caliber in predicting the sperm retrieval in NOA patients.
Materials And Methods:
Data from 143 infertile NOA men undergoing unilateral (64) or bilateral (79) microTESE (222 testes) were retrospectively evaluated. During microTESE, if present, dilated tubules (DTs) were retrieved, otherwise tubules with slightly larger caliber (SDT) (×24) than that of the surroundings were removed. When no DT or SDT were found, not dilated tubules (NDTs) were excised.
Results:
Spermatozoa were retrieved in 95 of 222 testes (42.8%); sperm retrieval was successful in 90% of testes with DTs, in 47% of those with SDTs, and only in 7% of those with NDTs (p < 0.0001). Stepwise binary logistic regression revealed that the combination of seminiferous tubule pattern and testis histology was significantly predictive of SSR, being able to classify 86.8% of testes, with an excellent diagnostic accuracy (AUC 0.93). The median number of spermatozoa retrieved was significantly higher in DTs compared with SDTs and NDTs.
Discussion:
The results of the present study provide reliable accuracy measures in support of the relationship between seminiferous tubule caliber pattern and SSR in patients with non-obstructive azoospermia. We are proposing for the first time that spermatozoa may be retrieved even from slightly dilated tubules in about half of cases. The pattern of tubules retrieved, together with histology, may represent an additional outcome measure of microTESE.
Conclusion:
The pattern of seminiferous tubules together with testis histology predicts sperm retrieval with an excellent diagnostic accuracy.
Related Concept Videos
01:15Sperm Transport
The maturation phase occurs in the epididymis, where sperm...
01:22Sperm Structure and Semen Composition
01:12Retrieval
Recall involves accessing information without cues, such as during an essay test, where individuals must retrieve facts and concepts from memory unaided. Another example is remembering the name of a colleague...
01:45ER Retrieval Pathway
The ER uses many checkpoints to prevent the entry of incorrectly folded or a resident protein as cargo onto a transport vesicle. These mechanisms...
02:27Predicting Molecular Geometry
01:24Renal Tubule and Collecting Duct
Proximal Convoluted Tubule (PCT):
The PCT is the initial segment of the renal tubule, extending from the Bowman's capsule that encloses the glomerulus. Its convoluted structure and microvilli-lined cells increase the surface area for reabsorption. The PCT reabsorbs glucose, amino acids, sodium, and water from the filtrate, ensuring essential...