What is the step‑by‑step procedure for micro‑dissection testicular sperm extraction (micro‑TESE) in a man with non‑obstructive azoospermia, testicular volume less than 12 mL, and appropriate genetic counseling?

Micro-TESE Surgical Procedure for Non-Obstructive Azoospermia

For men with non-obstructive azoospermia and testicular volume <12 mL who have completed appropriate genetic counseling, micro-TESE should be performed using wide opening of the tunica albuginea with systematic microsurgical examination of multiple testicular regions under 15-25X optical magnification to identify and extract dilated, opaque seminiferous tubules containing active spermatogenesis. 1

Pre-Operative Preparation

Before proceeding to the operating room, confirm the following have been completed:

• Genetic testing results reviewed: Verify karyotype and Y-chromosome microdeletion analysis are complete 2

  • Critical contraindication: Do NOT proceed if complete AZFa or AZFb deletions are present—sperm retrieval success is essentially zero 2
  • AZFc deletions are acceptable to proceed (53-75% retrieval rate) 2
  • Klinefelter syndrome patients can proceed (20-50% retrieval rate) 2

• Hormonal profile documented: FSH, LH, testosterone, and ideally AMH levels 2

  • Lower preoperative AMH correlates with higher sperm retrieval success 2
  • Baseline testosterone is important as post-operative androgen deficiency is a known risk 1

Surgical Technique: Step-by-Step

1. Anesthesia and Positioning

• General anesthesia or regional anesthesia
• Supine position with scrotal exposure
• Outpatient procedure 3

2. Incision and Exposure

• Make a midline scrotal incision or bilateral hemiscrotum incisions
• Deliver the testis through the incision
• Wide opening of the tunica albuginea is essential—this distinguishes micro-TESE from conventional TESE 1
• The wide opening allows visualization of multiple testicular regions without devascularization 1

3. Microsurgical Examination (15-25X Magnification)

• Use operating microscope at 15-25X magnification 3, 4
• Systematically examine seminiferous tubules in a centrifugal pattern parallel to intratesticular blood supply 1
• Search nearly all areas of the testis while preserving vascular integrity 1

4. Tubule Identification and Selection

• Target tubules that are: 3, 4
  • Larger in diameter (dilated)
  • More opaque (not translucent)
  • Whitish in appearance
• These characteristics indicate active spermatogenesis
• Avoid collapsed, translucent tubules which indicate absent spermatogenesis 3

5. Tissue Extraction

• Carefully excise identified dilated tubules with minimal tissue removal 3
• Extract multiple small samples from different testicular regions rather than large single samples
• Preserve testicular vasculature throughout to minimize ischemic damage

6. Intraoperative Laboratory Processing

• Immediately transfer extracted tissue to IVF laboratory 3
• Laboratory processes tissue to search for sperm
• Continue surgical exploration while laboratory examines specimens
• Operative time typically 90-120 minutes 3

7. Sperm Handling

• If sperm are found: cryopreserve all retrieved spermatozoa not immediately used for ICSI 3
• Document sperm quantity and quality for IVF team

8. Closure

• Close tunica albuginea with absorbable suture
• Close dartos and skin layers
• Apply scrotal support

Expected Outcomes

Sperm retrieval rates: 1

• Overall NOA: 40-60% success rate
• Micro-TESE is 1.5 times more successful than conventional TESE 1
• Hypospermatogenesis histology: highest retrieval rates 5
• Maturation arrest: intermediate rates
• Sertoli cell-only syndrome: lowest rates

Important caveat: FSH levels do NOT accurately predict sperm retrieval success in NOA patients, as men with maturation arrest can have normal FSH and testicular volume 2

Post-Operative Management and Complications

Immediate Recovery

• Return to normal activities within 5-7 days 3
• Minor testicular pain and scrotal swelling are expected 3
• Intraoperative blood loss is typically negligible 3

Long-Term Androgen Monitoring

• Critical complication: Post-operative testosterone deficiency 1, 5
• Testosterone levels significantly deteriorate immediately post-procedure 5
• Near complete recovery occurs after 1 year in most cases 5
• Monitor testosterone at 3,6, and 12 months post-operatively
• Micro-TESE causes less testosterone decline than conventional TESE, but testosterone replacement may still be required 1

Advantages Over Conventional TESE

• Higher sperm retrieval rates (1.5-fold improvement) 1
• Minimal postoperative complications 6, 5, 4
• Less testicular tissue removed 3
• Reduced processing time for laboratory 3
• Better preservation of testicular function 1

Patient-Specific Considerations

Testicular volume <12 mL (as in your patient): This smaller testicular size does NOT preclude micro-TESE success—patient age, testicular size, and FSH levels have shown no significant impact on sperm retrieval rates in multiple studies 5. The histological pattern is the primary determinant of success, not testicular volume.

Bilateral vs. unilateral approach: Start with the testis with better characteristics (larger volume, firmer consistency). If unsuccessful, proceed to contralateral testis during the same procedure to avoid repeat surgery.