Excerpts from the study on everything that concerns hearing preservation:
Cochlear nerve (hearing) preservation
Cochlear nerve preservation has been reported by many authors10,11,18,29,30 in the recent past, but there is a lot of ambiguity on the criteria for useful hearing. In addition, there are some who believe that the goal of gross total tumor removal cannot be achieved with cochlear nerve preservation.31
In this report, our rate of functional hearing preservation (213/374) (57%) reflects the better outcome associated with better visualization by the angled and zero-degree high-definition endoscopes. The fact that most tumors in this series were less than 4 cm in diameter and presented early with minimal symptoms also has a direct impact on the surgical outcome and prognosis.
Functional hearing preservation, being defined as measurable hearing (serviceable/some), was possible in 213/374 (57%) of the same group. One patient with a right sided intracanalicular VS, 10 mm in diameter and with a small portion of it protruding into the CPA, initially had “some†hearing and regained a “serviceable†hearing one week postoperatively. Another patient had an improvement of > 20 db in his hearing postoperatively
Table 3 : Cochlear Nerve (Hearing) Preservation
Serviceable/Some Total Deafness
Preoperative 374 153
Postoperative 213 314
More regarding facial nerve function:
In this series, at the time of discharge from the hospital, most of the patients had satisfactory facial nerve function with complete eye closure. After one year, 491/527 (93%) showed excellent facial nerve function (H-B grade 1/2), and 21/527 (4%) showed intermediate function (H-B grade 3/4).
In spite of the high rate of facial nerve preservation in this study, anatomical preservation of the facial nerve with complete tumor removal, especially in patients with large tumors, is still a challenge. Facial nerve monitoring has greatly aided separation of the facial nerve from the tumor.10,11,28-30
Hope it helps.
Eve