How reliable is the "scratch test" versus the Weber test after tympanomastoid surgery?

To identify whether the scratch test can be used as an alternative to the Weber's test after tympanomastoid surgery.

This twin-center prospective study assessed major tympanomastoid surgery patients over a 6-month period. Patients were assessed postoperatively on Day 0 or Day 1 of surgery using a standardized proforma. A Weber's test was performed using a 512-Hz tuning fork, placed midline on the forehead to assess the direction of sound localization. This was directly compared with a scratch test, by asking the patient the following while scratching the head bandage in the midline: "Can you hear this? And which side is loudest?"

Fifty-six patients were assessed in total. Sixteen mastoid explorations, 14 tympanoplasties, 18 combined approach tympanoplasties, and 8 other procedures were included, all of which had standard external auditory canal packing and head bandage. Assessment with Weber's test found 41 patients to have sound lateralizing to the operated ear. In comparison, 50 patients lateralized sound to the operated ear with the scratch test. Overall, Weber's test had a sensitivity of 73.2% and specificity of 100% compared with a sensitivity of 89.3% and specificity of 100% for the "Scratch Test." No patients had a dead ear after surgery.

The scratch test proved to be more accurate than traditional postoperative tuning fork assessment and provides a quick, accurate, and simple solution for when such equipment is unavailable.