Endoscopic Over-Under Cartilage Tympanoplasty Is Not Inferior to Endoscopic Underlay Cartilage Tympanoplasty

By June 7, 2019

Erbele, Isaac D.1; Fink, Madelinn R.2; Mankaker, Gauri1; Son, Leslie S.1; Arriaga, Moises A.1; Mehta, Rahul1
1 Louisiana State University Otolaryngology/Our Lady of the Lake Regional Medical Center, Baton Rouge, LA, US;
2 Louisiana State University Health Sciences Center, New Orleans, LA, US.

Introduction:
The endoscopic over-under cartilage tympanoplasty technique, where a cartilage and perichondrial graft is placed lateral to the malleus but medial to the annulus, addresses significantly retracted mallei and anterior superior perforations.  There is little outcome data, however, particularly regarding concerns that lifting the tympanic membrane from the malleus may worsen hearing.

Study Design:
Retrospective cohort

Setting:
Tertiary referral center

Patients:
Consecutive endoscopic over-under cartilage tympanoplasties age and gender matched to endoscopic underlay cartilage tympanoplasties by a single surgeon between January 2015 and January 2019.  Exclusion criteria included pre-operative cholesteatoma, performance of mastoidectomy or ossicular chain reconstruction, and lack of post-operative audiogram.

Intervention:
Endoscopic cartilage tympanoplasty via over-under or underlay technique.

Main Outcome Measures:
pre- and post-operative pure tone average and word recognition score, post-operative tympanic perforation, complications.

Results:
Thirty-five patients received over-under tympanoplasties in this period, and 27 had post-operative audiograms available.  Of the remaining patients, median follow up was 363 days.  Improvement in air conduction was statistically significant (p<0.0005) and averaged 9.5dB.  There were no post-operative perforations and no statistically significant change in bone conduction or word recognition score, but there was one cartilage donor site keloid.  There was statistical non-inferiority in improvement of air conduction when compared to 27 underlay tympanoplasties (p<0.05).  There were three post-operative perforations in the underlay group (11%).  No other significant complications were identified in either group.

Conclusions:
Endoscopic over-under cartilage tympanoplasty effective in select cases to improve hearing.  It is also safe, and post-operative perforation in the medium term is rare.