High-frequency conductive hearing loss as a diagnostic test for incomplete ossicular discontinuity in non-cholesteatomatous chronic suppurative otitis media

Chronic suppurative otitis media, with or without cholesteatoma, may lead to erosion of the ossicles and discontinuity of the ossicular chain. In incomplete ossicular discontinuity (IOD), partial erosion of the ossicles occurs, but some sound transmission is noted throughout the ossicular chain. High-frequency conductive hearing loss (HfCHL) has been considered a hallmark of incomplete ossicular discontinuity. This study aims to evaluate the use of HfCHL as a preoperative predictor of IOD in patients with non-cholesteatomatous chronic suppurative otitis media. The HfCHL test was defined as the preoperative air-bone gap (ABG) at 4 kHz minus the average of the ABG at 0.25 and 0.5 kHz. The test was applied in 328 patients before surgery and compared to intraoperative findings as the gold standard. At surgery, 201 (61.3%) patients had an intact ossicular chain, 44 (13.4%) had a complete ossicular discontinuity, and 83 (25.3%) exhibited an IOD. The best cutoff level was calculated as 10 dB. The HfCHL test to diagnose IOD had a sensitivity of 83% and a specificity of 92% with a post-test probability of 78% and a likelihood ratio of 10.2. We concluded that the HfCHL test is highly effective in predicting IOD in patients with non-cholesteatomatous chronic suppurative otitis media and that it should be used routinely as a screening test prior to surgery.

Erosion of the long process of the incus with incomplete ossicular discontinuity in simple chronic otitis media: Should we reconstruct or leave it be?

OBJECTIVE

To determine whether patients with simple chronic otitis media and incomplete ossicular discontinuity should undergo ossicular reconstruction.

DESIGN

Prospective, randomised surgical trial comparing no intervention with incus interposition over a 5-year period.

SETTING

Tertiary referral hospital.

PARTICIPANTS

Seventy-six participants with simple chronic otitis media and erosion of the long process of the incus but apparent good transmission throughout the ossicular chain as tested intra-operatively. Forty-four patients had partial erosion of the incus but still bony contact with the stapes head (Group A-Type I), and 32 had mainly connective tissue binding the incus and stapes (Group B-Type II). Each of these groups was randomised to either leaving the ossicular chain as it was (A1 and B1) or performing an incus interposition (A2 and B2).

MAIN OUTCOME MEASURES

Average postoperative air-bone gap and the degree of ABG closure. A postoperative air-bone gap under 20 dB was considered a successful result.

RESULTS

In group A, there was no significant difference between no intervention and incus interposition. In group B, patients in the no reconstruction subgroup had a significantly worse hearing result than the incus interposition subgroup (postoperative air-bone gap of 27.5 dB and 31% closure within 20 dB vs 15 dB and 75% closure).

CONCLUSIONS

For Type I patients, the postoperative hearing results were similar for the reconstruction and no reconstruction groups. For Type II patients, the results clearly favour reconstruction.