Evaluation of inlay butterfly cartilage tympanoplasty: a randomized clinical trial

In 1998 Eavey described a new inlay technique for tympanoplasty in the pediatric age group using a cartilage graft through a transcanal approach. This technique was found to be effective and comfortable (no external canal incisions or ear packing). This study evaluated the efficacy of modified-inlay cartilage tympanoplasty compared with the conventional underlay tympanoplasty.

Randomized clinical trial.

Patients were enrolled from December 1998 to March 2000. Seventy tympanoplasties were done in adults with medium-sized tympanic membrane (TM) perforations: 34 inlay tympanoplasties and 36 underlay tympanoplasties (control group). The main outcome measures were the "take rate" on the 30th postoperative day and the audiometric result at the second postoperative month. Secondary outcome measures include subjective postoperative hearing, postoperative pain, duration of surgery, and cost of the procedures.

The "take rate" did not differ between groups on the 30th postoperative day (88.2% in the inlay tympanoplasty group vs 86.1% in the underlay tympanoplasty group; P =.8). After a mean follow-up of 7.5 +/- 3.8 months (range, 3-16 mo), the "take rate" was 85.3% in the inlay tympanoplasty group and 83.3% in the underlay tympanoplasty group (P =.8). In the inlay tympanoplasty group there was closure of the air-bone gap (ABG) to within 10 dB in 64.7% and to within 20 dB in 94.1%. The corresponding numbers to underlay tympanoplasty were 75% and 97.2%. In only 2 cases (5.9%) in the inlay tympanoplasty group and in 1 case (2.8%) in the underlay tympanoplasty group the ABG was greater than 20 dB. No audiometric difference was observed between groups (P =.6). Most patients in the inlay tympanoplasty group reported immediate improvement in their hearing (P <.0001). Pain was reported by 10 patients in the inlay tympanoplasty group and by 30 patients in the underlay tympanoplasty group on the first postoperative day (P <.0001). The duration of the surgery (mean +/- standard deviation) was 33.6 +/- 7.8 minutes for the inlay tympanoplasty group and 62.9 +/- 12.7 minutes for the underlay tympanoplasty group (P <.0001). The estimated charge for inlay tympanoplasty at our institution was 65% less expensive than underlay tympanoplasty.

The "take rate" and audiometric results following inlay cartilage tympanoplasty or underlay tympanoplasty were similar. Inlay butterfly cartilage tympanoplasty did not require general anesthesia, was less expensive, and more comfortable to the patient.