Audiograms were performed preoperatively and 2 days postoperatively in 28 patients given spinal anesthesia for transurethral resection of the prostate. In 14 patients 22-gauge and in 14 patients 26-gauge spinal needles were used. Hearing loss of 10 dB or more at any frequency was observed in 13 of 14 patients in the 22-gauge group and in 4 of 14 patients in the 26-gauge group. There was a statistically significant reduction in hearing level in the low-frequency range in patients in whom the 22-gauge needle was used. Hearing loss was unilateral at five frequencies and bilateral at one frequency. No cases of postspinal headache occurred. Audiometry may be a more sensitive indication of cerebrospinal fluid leak than postspinal headache.