Does Attempt at Hearing Preservation Microsurgery of Vestibular Schwannoma Affect Postoperative Tinnitus?

Table 1

Factors affecting hearing preservation among the patients with preoperatively serviceable hearing.

	Hearing preserved	Deafness
	17	64
Size (mm)	19 ± 9 (11–40)	29 ± 11 (9–59)	<0.01
Grading (Koos)	G1: 2; G2: 4; G3: 7; G4: 4	G1: 1; G2: 3; G3: 11; G4a: 45; G4b: 4	0.02
Preoperative hearing level	GRC1: 6; GRC2: 7; GRC3: 2; GRC4: 2	GRC1: 12; GRC2: 18; GRC3: 20; GRC4: 4	<0.01
Type of BAEP response	H2: 5; H3: 4; H4: 1; H5: 7	H1: 1; H2: 8; H3: 10; H4: 2; H5: 51	0.03
Intraoperative BAEP	8	4	<0.01
Soft tumor consistency	7	21	0.03
Tumor adhesion	4	45	<0.01

GRC: Gardner-Robertson’s classification; BAEP: brainstem auditory evoked potentials; H: Hannover classification of BAEP response.