P-076 Standard IV cannula aspiration of testicular sperm: A novel, efficient and minimally invasive aspiration technique

Abstract

Abstract Study question Can we aspirate enough testicular tissue for sperm retrieval in non-obstructive azoospermia (NOA), using a wide bore 14-G Standard IV cannula in comparison to micro-TESE? Summary answer Standard IV cannula Aspiration (SIVCA) can yield an ample amount of testicular tissue sufficient for sperm retrieval through a single puncture site on the scrotum. What is known already The current conventional method of testicular sperm aspiration is fine needle aspiration (FNA). FNA has the advantage of being a cost-effective and minimally invasive procedure compared to open testicular sperm extraction (TESE). But FNA with its conventional 23-G needle may not always yield enough testicular tissue for sperm retrieval. Furthermore, FNA may require multiple punctures on the scrotum to retrieve enough tissues from different areas of the testis. Study design, size, duration A 24 months prospective cohort study conducted at a specialized IVF center. A total of 130 men aged from 22 to 53 years old (35.03 +/- 9.04) with NOA and normal testicular volume (≥ 12ml) were enrolled in the study. The men had testicular biopsies taken at the day of their partners’ ovum pick-up. On each patient, the testes were randomized to undergo SIVCA on one testis followed by micro-TESE on the contralateral testis. Participants/materials, setting, methods After local anesthesia, a wide bore 14-G standard IV cannula was introduced near the lower pole of the testis. The needle was withdrawn and the catheter introduced into the testicular tissue. A 20-ml syringe was secured to the catheter and constant negative pressure applied and secured with a clamp. Back and forth motions were performed covering as many areas of the testis as possible. Micro-TESE was then performed on the contralateral testis. Main results and the role of chance Sperm retrieval rates (SRR) were compared between the two techniques using McNemar χ2 test. A P-value of less than 0.05 was considered to be statistically significant. Out of a total of 130 cases, an adequate tissue sample could successfully be aspirated using SIVCA in 122 cases, showing a 0.93 probability of success. In those 8 cases where SIVCA had not yielded sufficient tissue and were reverted to micro-TESE, 2 cases were positive for sperm retrieval. Whenever tissue aspiration was successful with both methods, both SIVCA and micro-TESE showed similar success rate with respect to SRR (56.2 vs 57.3%; McNemar P = 1.000). Limitations, reasons for caution Both FNA and SIVCA are not easy to perform on small sized testes. Moreover if testicular tissue is fibrotic or sclerotic, it may be difficult to aspirate and micro-TESE would be the ideal choice to yield enough testicular tissue. Further blinded randomized control studies with larger datasets are recommended. Wider implications of the findings The use of a peripheral IV wide bore cannula is suitable for the aspiration of adequate amounts of testicular tissue for sperm searching whilst requiring only a single puncture on the scrotum. We recommend routinely starting off with SIVCA to search for sperm before reverting to micro-TESE. Trial registration number Unique Protocol ID: SIVCA Protocol registration Records number will be made available to the public through the ClinicalTrials.gov web site within 2 to 5 days of today 31/1/2022