Dr/ Mohebat Helmy Lecturer of pathology

Diagrammatic view of testis, epididymis, and portion of ductus (vas) deferens.

Scrotal covering layers and capsule of testis.

Spermatogonia ( solid arrowhead ), primary spermatocytes ( open arrowhead ), Sertoli cells ( arrow ), and fibromyocyte of tunica propria ( solid triangle ). The smaller cells in the lower right are mainly secondary spermatocytes and early spermatids.

Seminiferous tubule with Sertoli cells ( long arrows ), spermatogonia (”), primary spermatocytes ( -²), and spermatids ( short arrow ).

Sertoli cell with intracytoplasmic Charcot-B ttcher crystalloids ( arrow ) from a patient with germ cell aplasia. Note the prominent nucleolus and slightly wrinkled nuclear membrane.

Scoring of testicular biopsy for infertility Several methods have been proposed for quantitatively assessing the germ cell elements and the relationship of spermatogenesis to seminal fluid sperm density.

Not all spermatogonia or spermatocytes progress to become spermatozoa and that apoptotic or degenerative changes in these precursor cells can be seen regularly in the seminiferous tubules. This normal physiologic process should not be mistaken for maturation arrest.

A cross-sectional view of seminiferous tubule and interstitium. Germ cell maturation is variable around the tubule, a normal finding.

Secondary spermatocytes are rarely found and cannot be differentiated from early spermatides very easily.

Late spermatide may look very much like a mature spermatozoan, if it is still part of the tubular epithelium, it is still a spermatid. It becomes a spermatozoan only when it is released.

An average of 10 to 12 Sertoli cells per tubule cross section is considered normal, and approximately half the germ cell elements within the tubule should be in the spermatid stage. The Germ/Sertoli ratio is relatively constant at approximately 13:1 in young healthy men (20-48).

Common finding in patients with oligozoospermia or azoospermia due to primary testicular failure is the accumulation of eosinophilic, acellular material in the lamina propria. This material is an admixture of increased collagen fibers, elastic fibrils, and basement membrane “like materia

According to the histopathology criteria; testicular biopsy specimens were classified histological as: Normal Histology Hypospermatogenesis Spermatocytic arrest Sertoli cell only Tubular fibrosis

One of them applies Johnson score (a score of 1 to 10) for each tubule cross section examined, according to the following criteria:

10: Complete spermatogenesis and perfect tubules. 9:Many spermatozoa present but disorganized spermatogenesis. 8:Only a few spermatozoa present. 7:No spermatozoa but many spermatids present. 6:Only a few spermatids present. 5:No spermatozoa or spermatids present but many spermatocytes present. 4:Only a few spermatocytes present. 3:Only spermatogonia present. 2:No germ cells present. 1:No germ cells or Sertoli cells present.

The first method: detecting a germ cell to Sertoli cell ratio by counting at least 30 tubule cross sections. This ratio is relatively constant at approximately 13:1 in young healthy men. An average of 10 to 12 Sertoli cells per tubule cross section is considered normal, and approximately half the germ cell elements within the tubule should be in the spermatid stage. An assumption is made that the Sertoli cell population is stable throughout adult life. A reasonably good assessment of the presence or absence of hypospermatogenesis or maturation arrest can be made with this technique.

In a normal adult testicle, the mean score count should be at least 8.90, with an average of 9.38, and 60% or more of the tubules should score at 10.

A second method: involves counting spermatids per tubule cross section :Only the mature spermatids, that is those with oval nuclei and dark, densely stained chromatin, are counted. Excellent correlations have been made with seminal fluid sperm counts. A spermatid/tubule cross section count of 45 corresponds to a seminal fluid sperm count of 85 — 10 6 /mL. Spermatid/tubule counts of 40, 20, and 6 to 10 correspond to sperm counts of 45, 10, and 3 — 10 6 /mL, respectively. A minimum of 20 tubules must be counted.