Radiation Therapy and Hearing Loss

Mean dose response for sensorineural hearing loss (SNHL) at (a): 4 kHz; (b): 0.5–2 kHz; and (c): all frequencies (0.25–12 kHz). Data from: Figure 3 of Chen et al. (6) (retrospective study; SNHL defined as a ≥20-dB increase in the bone-conduction threshold at ≥1 year; patients received concurrent and adjuvant cisplatin chemotherapy); Figure 1 of Honore et al. (10) (retrospective study; SNHL defined as 20-dB increase in the bone-conduction threshold at ∼0.5–6.5 years); Figure 2 of Pan et al. (5) (prospective study; SNHL defined as a 20-dB difference between bone-conduction thresholds for ipsilateral and contralateral ears at 1 year; doses are ipsilateral-ear mean doses minus contralateral-ear mean doses); Table 2 of Oh et al. (8) (prospective study; SNHL defined as a 15-dB increase in the bone-conduction threshold at 1 year; patients received neoadjuvant and concurrent cisplatin chemotherapy); of Kwong et al. (7) (prospective study; SNHL defined as a 15-dB increase in the bone-conduction threshold at 1 year; patients received neoadjuvant and concurrent chemotherapy; ears received the full prescription dose; prescriptions were converted to biologically effective dose in 2 Gy fractions using α/β = 3 Gy); Fig 2 of van der Putten et al. (12) (retrospective study; SNHL defined as a 15-dB increase in the average of all pure-tone thresholds at 2–17 years).

Axial computed tomography image through the skull base. EAC = external acoustic canal; C = cochlea; V = vestibule; IAC = internal auditory canal.