Percutaneous epididymal sperm aspiration (PESA) are available for men with obstructed or absent ejaculatory ducts (i.e. unsuccessful vasectomy reversal, congenital absence of the vas deferens). Sperm are aspirated directly from the epididymis (the tiny collecting tubules next to the testes) for use in the ICSI procedure. The few drops of fluid may contain sufficient sperm to be frozen for several ICSI procedures.
Testicular sperm extraction (TESE) is available for men with obstructions or ejaculatory problems that cannot be treated by any other method. Small samples of testicular tissue are obtained by needle biopsy and a few sperm are painstakingly dissected out of the tissue for use in the ICSI procedure.