Lateral-to-Malleus Underlay Tympanoplasty: Surgical Technique and Outcomes

Objective: The lateral-to-malleus underlay tympanoplasty (LMUT) involves dissection of the tympanic membrane remnant from the malleus with subsequent graft placement medial to the annulus but lateral to the malleus. The objective of the current study is to describe the clinical outcomes using the LMUT technique. Patients: One hundred forty-one ears undergoing LMUT. To isolate the effects of tympanoplasty on audiometric outcome, only cases with an intact and mobile ossicular chain were evaluated; ears with ossicular discontinuity, fixation, and/or ossicular chain reconstruction were excluded. Intervention: Lateral-to-malleus underlay tympanoplasty. Main Outcome Measures: 1) Change in air-bone gap and bone conduction thresholds; 2) tympanic membrane lateralization; and 3) primary and delayed graft failure. Results: One hundred forty-one tympanoplasties were analyzed. In the early postoperative period, 140 (99%) of 141 grafts were intact and, at a mean of 32.1 months, 121 (85.8%) remained without significant retraction or reperforation. There were no cases of early or delayed graft lateralization. The mean preoperative and most recent postoperative air-bone gaps were 23.7 dB and 14.1 dB, respectively (p < 0.001). Surgery was not associated with a transient or long-term bone conduction threshold shift. Conclusion: The LMUT technique offers improved exposure of the tympanic space and a low rate of graft failure. The risks of sensorineural hearing loss with ossicular chain manipulation and tympanic membrane lateralization from graft placement lateral to the malleus are very low.