Intravenous Administration of 200ml Glycerol in Endolymphatic Hydrops

Abstract

For glycerol test, 500ml of 10% glycerol solution was given intravenously to prevent glycerol-induced hemolysis and the other side effects. However, to shorten the test procedure and to avoid the side effects we administered only 200ml of glycerol intravenously to 17 ears with Meniere's disease, 4 ears with syphilitic labyrinthitis, one with contralateral delayed endolymphatic hydrops. Pure tone audiometry and sampling of blood were performed before and 30, and 60 minutes after intravenously administration of glycerol. From the blood samples, the concentration of glycerol and serum osmolality were investigated.
We performed both 200ml and 500ml glycerol tests separately in 17 ears with endolymphatic hydrops. Only 2 ears out of 17 ears showed different test results. There were also no statistical differences between the 200ml and 500ml methods in terms of improvement in pure tone threshold between 125Hz and 8000Hz. There were some differences in the blood concentration of glycerol and in serum osmolality when 200ml or 500ml of glycerol was used intravenously or 50g orally. Only two of 22 patients who were given 200ml of glycerol showed side effects as nausea and headache. Of 22 ears with endolymphatic hydrops who underwent 200ml glycerol test, 11 ears (50%) were regarded as positive.
Klockhoff and Lindblom's original method and the other reported methods require more than 3 hours for glycerol test. This long test duration made some patients tired. Oral administration also gave them much more side effects than our 200ml method.