Stabilising total ossicular replacement prosthesis for ossiculoplasty with an absent malleus in canal wall down tympanomastoidectomy – a randomised controlled study

Abstract

To compare two titanium total ossicular replacement prosthesis (TORP) stabilisation techniques in canal wall down mastoidectomy presenting with footplate only and absent malleus handle. Prospective, controlled, randomised study. Tertiary Otology Department. Patients operated on with canal wall down mastoidectomy between 1999 and 2009 were randomised into two groups. Two techniques enhancing the TORP stability were compared: Hüttenbrink's method (63 patients, Group 1) and author's (GB) procedure (62 patients, Group 2). Hüttenbrink's technique consists in placing a cartilage shave with a hole in the middle over the footplate. Through this hole, the end of the TORP is accommodated. The author's method involves using a cartilage split in the middle, to lodge the TORP's shaft at one end and to lay the opposite end over the fallopian canal. Mean postoperative air-bone gap, hearing gain and air-bone gap closure within 20 dB. Auditory outcomes were evaluated at 1 year postoperatively. Postoperative air-bone gap closure within 20 dB (successful outcome) at 1 year was achieved in 59% of patients in Group 1 and 72% in Group 2 (P = 0.03). Mean postoperative air-bone gap was 24.4 ± 10.8 dB for Group 1 and 20.17 ± 9.8 dB for Group 2. The difference is 4.23 dB (95% confidence interval, 0.65-07.81), statistically significant: P = 0.02. Hearing gain was 20.3 ± 9.5 in Group 1 and 25.1 ± 10.2 in Group 2, significantly superior: P = 0.007. Better hearing outcomes for author's method could be demonstrated, but our sample size cannot exclude small and possible trivial, group differences.