Tone decay test

[1][2] A tone at the frequency of 4000 Hz is presented for 60 seconds at an intensity of 5 decibels above the patient's absolute threshold of hearing.

[1] TD is a procedure for diagnosing retro-cochlear pathology (RCP, damage to the auditory nerve).

[citation needed] According to Rosenberg, 1958: Marked tone decay indicates probability of RCP[3].

[citation needed] Glaslow, 1968 stated that positive TD is one where there is at least 30 dB decay.

[citation needed] The index of suspicion should also be raised if the rate of decay does not diminish with increased stimulus intensity.

Reverse Recruitment / Decruitment is a hallmark feature of SNHL of Retro Cochlear region.