Consequences of middle ear bone dust during neurotologic surgery

Ossicular fixation caused by bone dust after saccus decompression surgery

HYPOTHESIS

To highlight the clinical and histologic features of ossicular fixation produced by bone dust during mastoid surgery.

BACKGROUND

Bone dust deposition in the middle ear may occur during temporal bone surgery, but the ossicular fixation that may result from it remains underreported.

METHODS

A case is reported of delayed conductive hearing loss after saccus decompression surgery resulting from ossicular fixation by bone dust deposition.

RESULTS

Six months after the initial surgery, the patient experienced a 45 dB conductive hearing loss. The findings on second-look tympanotomy were stapes fixation and round window niche occlusion by newly formed tissue. Histologic examination of the latter showed fibrosis and new bone formation in reaction to particles of bone dust. New bone formation is a frequent concomitant of fibrosis in the middle ear and is probably not a growth from the bone dust.

CONCLUSION

The use of high-speed drilling of bone in temporal bone surgery carries the risk of bone dust particle deposition in the middle ear. Measures are discussed that can be used to prevent this complication.

Masking the Protrusion of the Receiver-Stimulator of Electronic Implants in Otology

Protrusion of the receiver-stimulator of a cochlear implant or a piezoelectric implantable hearing aid (IHA) was masked using bone dust applied in the gap between the receiver and the surrounding bone, making a smooth transitional border. The bone dust was then fixed with fibrin glue. Bone pâté (a mixture of bone dust and fibrin glue) was also used to fix the lead wire of a cochlear implant at the region of the posterior tympanotomy and to fasten an IHA vibrator holder to the temporal bone. Over the past two years, the use of these techniques in six patients with cochlear implants and two patients with IHAs has resulted in gratifying results; the edge of the receiver remained flush in all cases. They have been free from problems such as infection of the wound, necrosis of the overlying skin, and protrusion or migration of the receiver.