Participant 22 is a 52;10 year old male who was diagnosed with SCC of the oropharynx in 2005. The participant was aged 48;9 years at the time of beginning concurrent cisplatin and irradiation therapy. Eight days prior to commencing treatment, the participant underwent audiological assessment that involved standard pure-tone audiometry, EHF pure-tone audiometry and tympanometry. Standard pure-tone audiometry showed normal hearing sloping to a moderate mixed loss in the left ear, and normal hearing sloping to a mild sensorineural hearing loss in the right ear. The PTA was 20 dB HL bilaterally. EHF pure-tone audiometry showed a moderate to moderately-severe hearing loss with a loss of response above 14 kHz in the left ear. In the right ear, testing showed a moderate sloping to a severe hearing loss with a loss of response above 12.5 kHz in the right ear. Tympanometry yielded a type ―A‖ tympanogram in the left ear, consistent with normal middle ear pressure and compliance, and a type ―Ad‖ in the right ear, consistent with greater than normal compliance.
Participant 22 received one dose of 187 mg cisplatin on day one of the treatment protocol.
Twenty days later the participant complained of hearing loss and was subsequently sent for audiological assessment. Standard pure-tone audiometry showed deterioration of high-frequency thresholds with a decrease of 15 dB at 8 kHz in the left ear, and 15 dB at 4 kHz, 30 dB at 6 kHz and 40 dB at 8 kHz in the right ear. EHF pure-tone audiometry showed a 20 dB decrease at 10 kHz and 11.2 kHz in the left ear, and a 15 dB decrease at 9 kHz and 10 kHz and loss of response at 11.2 and 12.5 kHz in the right ear. Tympanometry remained stable, indicating no middle ear effusion. Analysis of thresholds in relation to the ASHA criteria indicated a significant cochleotoxic change, fulfilling criteria 1 and 2 bilaterally. Due to this change in hearing, the second dose was withheld. Twenty one days later the participant was reassessed prior to the scheduled third cisplatin dose. Standard audiometry indicated further deterioration in the right ear only, with an additional decrease of 15 dB at 0.25 kHz and 0.5 kHz, 20 dB at 2 kHz and 15 dB at 4 kHz. Bone conduction results indicated this was a mixed hearing loss. EHF audiometry did not show any significant change (≥ 15 dB) in hearing thresholds in either the left or right ear.
Tympanometry remained stable in the right ear but suggested reduced compliance in the left ear (type ―As‖ tympanogram). Analysis of thresholds in relation to the ASHA criteria continued to indicate a significant cochleotoxic change, fulfilling criteria 1 and 2
bilaterally The third dose was also withheld due to the further deterioration in hearing on the right side.
Post-treatment assessment was carried out for the purpose of this research in January 2010. The participant reported sudden hearing loss, particularly in his right ear that he believed developed with cisplatin treatment. He reported difficulty hearing in group situations and when there is background noise. He felt that he had the television and radio turned up louder than other family members would like. Participant 22 also
reported unilateral tinnitus in his left ear, the onset of which coincided with the single dose of cisplatin. He described it as a high pitch ringing that was of minimal annoyance.
He had a history of occupational noise exposure of approximately 20 years duration, but did not wear hearing protection. Standard pure-tone audiometry showed a mild to moderate sloping sensorineural hearing loss in the left ear, and a mild to moderately-severe sloping mixed hearing loss in the right ear. Standard PTA was 32.5 dB HL for the left ear and 30 dB HL for the right ear. EHF pure-tone audiometry showed a moderate to moderately-severe flat hearing loss in the left ear and a severe to profound hearing loss in the right ear. EHF PTA was 56.25 dB HL in the left ear and 86.25 dB HL in the right ear.
Tympanometry yielded a type ―A‖ tympanogram in the left ear, consistent with normal middle ear pressure and compliance, and a type ―Ad‖ tympanogram in the right ear, consistent with increased compliance. Speech audiometry at a presentation level of 65 dB HL yielded 94% in the left ear and 100% in the right ear. Speech presentation at 55 dB HL and 40 dB HL in the left ear yielded 74% and 54% respectively. Speech presentation at 50 dB HL and 35 dB HL in the right ear yielded 80% and 21% respectively. DPOAEs were present in the right ear at 2, 2.5, 3.062, 4.062, 4.5 and 5.5 kHz, and in left ear at 2, 2.25, 4.5 and 6.125 kHz. Ipsilateral acoustic reflexes were present at normal presentation levels in the left ear from 0.5 to 2 kHz and absent at 4 kHz. Reflexes were absent from 0.5 to 4 kHz in the right ear. Analysis of thresholds in relation to the ASHA criteria indicated a significant cochleotoxic change, fulfilling criteria 1 and 2 bilaterally. Audiometric data for participant 22 are detailed in Figure 3.10.
Figure 3.10: Illustration of hearing thresholds in decibel hearing level (dB HL) at 0.25 to 16 kHz for the left ear (top) and right ear (bottom). Thresholds are shown as a function of time from the initial cisplatin dose (0 months) to post-treatment assessment. The vertical lines indicate cisplatin doses. Dashed coloured lines indicate extended high-frequency thresholds. No response at the limits of the audiometer is indicated by an arrow, with those intensities joined by dotted lines.
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Pure-tone hearing threshold (dB HL)
Time re: first cisplatin dose (months)
250 Hz
Pure-tone hearing threshold (dB HL)
Time re: first cisplatin dose (months)
250 Hz