Vestibular function disorders and potential mechanisms in irradiation nasopharyngeal carcinoma patients

Abstract

Thirty-eight patients were included. The incidences of abnormal ocular VEMP (oVEMP) and cervical VEMP (cVEMP) were 65.79% and 80.26% at the time of completion of radiotherapy, and 61.84% and 71.05% at 3 months after radiotherapy. The mean and maximum radiation doses to the inner ears were both significantly associated with abnormal oVEMP and cVEMP (p < 0.05, all), but the correlations were all mild. The serum levels of IL-6 and IL-17 were both significantly associated with abnormal oVEMP and cVEMP after irradiation (p < 0.05, all).

Irradiated ears in nasopharyngeal carcinoma survivors: A review

“…For those with peripheral vertigo, controlling ROM by local cleansing of the inflamed regions is suggested to lessen the middle ear inflammation, thereby preventing later onset vertigo. In contrast, enhancing perfusion of the inner ear by plasma expander is recommended for NPC survivors with central vertigo …”

“…In contrast, enhancing perfusion of the inner ear by plasma expander is recommended for NPC survivors with central vertigo. 44,47,51…”

A unique radioprotective effect of resolvin E1 reduces irradiation-induced damage to the inner ear by inhibiting the inflammatory response

“…In this study, we also observed hearing loss in mice, evaluated by ABR, along with HE staining, whole-mount staining and SEM showing various degrees of damage to the cochlea basal membrane hair cells and spiral ganglion cells after irradiation. Post-irradiation vestibular dysfunction has rarely been reported, and our previous study found an incidence of post-irradiation vestibular dysfunction of up to 60-70% in clinical practice [9], but the mechanism has not previously been reported. In this study, post-irradiation vestibular dysfunction in mice was also indicated by the results of relative balance ability tests, and HE staining, whole-mount staining and SEM all showed that damage to utriculus and sacculus hair cells after irradiation was the main cause of postirradiation vestibular dysfunction.…”

“…Some studies have reported that the inflammatory response induced by irradiation can cause apoptosis of hair cells. Our previous clinical study found an abnormal increase of IL-6 in the peripheral blood of patients with radiation-induced inner ear damage [9], and another study found that a large number of inflammatory cells appeared in the vestibular tissue of irradiated guinea pigs [10]. These studies imply that the inflammation induced by irradiation may play an important role in damage to the inner ear, but there is a lack of complete experimental evidence in support of this hypothesis.…”

“…SNHL and vestibular dysfunction after irradiation are caused by damage to the inner and outer hair cells, spiral ganglion and vestibular hair cells. Direct effects of the irradiation dose on the inner ear are not solely responsible for the damage to the cochlea and vestibule [8,9].…”