Correlation of postoperative ear canal volumes with obliteration material and with volume of operation cavity

External Auditory Canal Reconstruction and Mastoid Obliteration Using Modified Palva Flap in Canal Wall Down Mastoidectomy With Tympanoplasty

OBJECTIVE

To evaluate the effectiveness of a modified Palva flap used for external auditory canal reconstruction and mastoid obliteration in canal wall down mastoidectomy.

METHODS

We retrospectively analyzed patients who underwent canal wall down mastoidectomy with tympanoplasty using modified Palva flap. All patients underwent pure tone audiometry and temporal bone computed tomography (CT) before surgery, and the same tests were performed in the first year after surgery. The external auditory canal volumes were calculated by summing the areas of each section selected in temporal bone CT. For each patient, the ratio of external auditory canal volume was calculated from CT taken before and after surgery.

RESULTS

The mean of external auditory canal volume after canal wall down with a modified Palva flap was about 1.4 times larger than before surgery. The modified Palva flap is effective for the reconstruction of the external auditory canal. Both pure tone audiometry level and air-bone gap showed statistically significant improvement after surgery ( Ps = .001 and .002, respectively).

CONCLUSIONS

The external auditory canal volume slightly increased, but the status of mastoid obliteration was well maintained 1 year after surgery. The modified Palva flap used in this study is an easy and effective method in external auditory canal reconstruction and mastoid obliteration.

Canal wall reconstruction and mastoid obliteration in canal wall down tympanomastoidectomized patients

CONCLUSION

Posterior canal reconstruction using autogenous bone pate and mastoid obliteration with allogenous cancellous bone chips (ACBCs) is a useful method to eliminate cavity problems after canal wall down tympanomastoidectomy (CWDT). It is also an appropriate method to obtain adequate middle ear space for hearing gain and to apply hearing aids for patients with poor eustachian tube function after surgery.

OBJECTIVE

This study was performed to suggest a new technique for posterior canal reconstruction and mastoid obliteration and to evaluate the outcome of the surgery.

PATIENTS AND METHODS

The entire posterior canal was reconstructed with autogenous bone pate, and the new isolated mastoid cavity was obliterated with ACBCs in patients who had undergone CWDT and suffered from cavity problems. Outcomes were measured by external auditory canal shape, condition of the neotympanum, hearing outcome, improvement of cavity problems, and surgical complications.

RESULTS

In 90.9%, the reconstructed canal wall maintained a cylindrical shape. The drum healed without perforation/retraction in 90.9%. The average air-bone gap value was 34.5 dB hearing level (HL) before the staged operation and 17.8 dB HL after the staged operation; 95.5% had no more cavity problems. Minor postauricular wound infection was the most common complication (13.6%).