Prehabilitation with Intratympanic Gentamycin in Vestibular Schwannoma Patients and Postoperative Contralateral Benefits: A Prospective Study

Objective To determine the impact of preoperative intratympanic gentamycin injection on patients undergoing translabyrinthine resection of vestibular schwannomas (VS).

Methods This is a case comparison pilot study of eight patients undergoing translabyrinthine resection of VS. Group 1 consisted of four patients who did not receive preoperative intratympanic gentamycin and group 2 consisted of four patients who received preoperative intratympanic gentamycin. All patients underwent postoperative six-canal video head impulse test (vHIT); the patients from group 2 also underwent pre- and postinjection six-canal vHIT. We looked into the length of inpatient stay, their recovery, and the contralateral semicircular canal function.

Results The average postoperative length of stay in the patients who did not receive intratympanic gentamycin was 9.5 days, while in those who did, it was only 6.5 days. All patients achieved good balance results with the nongentamycin group requiring more time. Additionally, the gentamycin group had normal postoperative vHIT results in the contralateral ear, while the nongentamycin group had abnormal vHIT results in at least one contralateral semicircular canal. Of note, in those patients who received intratympanic injections, the middle ear was noted to have some mild fibrosis, a finding of no clinical significance.

Conclusion Our pilot study demonstrates that preoperative gentamycin ablation of the labyrinth may benefit patients undergoing VS resection. Additionally, we show for the first time the impact of the translabyrinthine resection on the contralateral side and how this is eliminated by the preoperative gentamycin injections.