We tested hearing thresholds at frequencies from 250 to 8000 Hz (Grason-Stadler GSI 61 audiometer) in a sound-attenuating room. The degree of hearing impairment was defined by the pure tone average (PTA) threshold levels at 0.5, 1, 2 and 4 kHz, and was classified as mild (PTA 21–40 dB HL), moderate (PTA 41–70 dB HL), severe (PTA 71–95 dB HL) and profound (PTA >95 dB HL) (Study group on terminology, definition and hearing assessment, 1996; Martini et al., 1997 (link)).
Acoustic reflex thresholds were measured ipsilaterally and contralaterally to the stimulated ear (Grason-Stadler GSI TympStar impedance audiometer). They were considered absent when no response was found at intensities >110 dB HL.
In implanted patients, aided thresholds were measured (Interacoustic AC30 Audiometer connected to a Pioneer A 103 amplifier, JBL TLX130 loudspeakers) with subjects wearing their sound processor on user settings. Warble tone stimuli were presented in the free-field at octave frequencies from 250 to 4000 Hz. To avoid contralateral acoustic stimulation, the ear canal was occluded with an earplug.
Acoustic reflex thresholds were measured ipsilaterally and contralaterally to the stimulated ear (Grason-Stadler GSI TympStar impedance audiometer). They were considered absent when no response was found at intensities >110 dB HL.
In implanted patients, aided thresholds were measured (Interacoustic AC30 Audiometer connected to a Pioneer A 103 amplifier, JBL TLX130 loudspeakers) with subjects wearing their sound processor on user settings. Warble tone stimuli were presented in the free-field at octave frequencies from 250 to 4000 Hz. To avoid contralateral acoustic stimulation, the ear canal was occluded with an earplug.