Combined Heermann and Tos (CHAT) technique in cholesteatoma surgery: surgical technique and preliminary results

The combined Heermann and Tos (CHAT) technique is the combination of Heermann's 'cartilage palisade tympanoplasty' and Tos's 'modified combined approach tympanoplasty = modified intact canal wall mastoidectomy'. The first author (Cem Uzun) performed the CHAT technique as a one-stage operation in 15 ears of 15 patients with cholesteatoma. Two patients (one with a follow up of less than six months and one who did not show up at the final re-evaluation) were excluded from the study. Median age in the remaining 13 patients was 37 years (range: 14-57 years). Cholesteatoma type was attic, sinus (Tos tensa type 1) and tensa retraction (Tos tensa type 2) in six, five and two ears, respectively. Cholesteatoma stage was Saleh and Mills stage 1, 2, 3, 4 and 5 in one, three, four, four and one ear, respectively. The eustachian tube was not involved with cholesteatoma in any ear. After drilling of the superoposterior bony annulus, transcanal atticotomy with preservation of thin bridge and cortical mastoidectomy with intact canal wall, the cholesteatoma was removed, and the eardrum and atticotomy were reconstructed with palisades of auricular cartilage. Type I tympanoplasty was performed in two ears, type II in nine ears and type III (stapes absent) in two ears, with either autologous incus (eight cases), cortical bone (two) or auricular cartilage (one). No complication occurred before, during or after surgery. Oto-microscopy and audiometry were done before and at a median of 13 months after surgery (mean 14 months, range 7-30 months). There was no sign of residual or recurrent cholesteatoma in any patient during the follow-up period. At the final examination, all ears were dry and had an intact eardrum except one with a small, central hole, which had been seen since the early post-operative period. Clean and stable attic retraction with a wide access was observed in two ears. Post-operative hearing at the final evaluation was better (change > 10 dB) than the pre-operative one in nine ears and did not change in the remaining four. Pre- and post-operative mean hearing values were, pure-tone average 47 and 35 dB (p = 0.01) and air-bone gap 30 and 20 dB (p = 0.02), respectively. With the CHAT technique, cholesteatoma can be completely and safely removed from the middle ear, and a durable and resistant reconstruction of the middle ear with reasonable hearing can be achieved. However, a further study should analyse long-term results of a larger patient group.