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ObjectiveWe compared the characteristics of air-conducted sound cervical vestibular evoked myogenic potential (ACS-cVEMP) and bone-conducted vibration cVEMP (BCV-cVEMP) among 3-month-old infants with normal hearing and sensorineural hearing loss (SNHL), and healthy adults to explore the feasibility and optimal strategies for infant vestibular screening.Methods29 infants (58 ears) were divided into two groups according to hearing (group I: normal hearing ears; group II: SNHL ears), 20 healthy adults were defined as group III. The results of response rate, P13 and N23 latency, P13-N23 interval, amplitudes, and corrected interaural asymmetry ratio (IAR) were recorded and compared among three groups.ResultsThe response rates of ACS-cVEMP in three groups were 88.89, 62.00, 100%, respectively. The P13 and N23 latencies, and P13-N23 interval did not differ significantly between group I and II (p = 0.866, p = 0.190, p = 0.252). A significant difference was found between group I and III (p = 0.016, p < 0.001, p < 0.001). No significant difference was observed in raw or corrected amplitude between group I and II (p = 0.741, p = 0.525), while raw and corrected amplitudes in group III were significantly larger than group I (p < 0.001, p < 0.001). For BCV-cVEMP, the response rates in three groups were 100, 86.36, 100%, respectively, No significant difference existed in the P13 and N23 latency, or P13-N23 interval between group I and II (p = 0.665, p = 0.925, p = 0.806), however, P13 and N23 latencies were significantly longer in group III than group I (p < 0.001, p = 0.018), but not in P13-N23 interval (p = 0.110). There was no significant difference in raw or corrected amplitude between group I and II (p = 0.771, p = 0.155) or in raw amplitude between group I and III (p = 0.093), however, a significant difference existed in corrected amplitude between group I and III (p < 0.001).ConclusionsCompared with adults, 3-month-old infants with normal hearing presented with equivalent response rates, shorter P13 and N23 latencies, smaller corrected amplitudes, and a wider IAR range for both ACS and BCV-cVEMP. SNHL infants had equivalent response rates of BCV-cVEMP, lower response rates of ACS-cVEMP than normal hearing infants. When responses were present, characteristics of ACS and BCV-cVEMP in SNHL infants were similar with normal hearing infants. ACS combined with BCV-cVEMP are recommended to improve the accuracy of vestibular screening.

The living anatomy of the vestibular end-organs is still unknown, complex, and studying them is a challenge for researchers in basic science and in clinical medicine. This main reason is the fact that we cannot observe the vestibular end-organs in the living subjects by any modern diagnostic facilities such as CT and MRI. We can make the three-dimensional virtual histology of the vestibular end-organs based on high-resolution computed tomography (HR-CT) of a human temporal bone with the use of the direct volume rendering. The three-dimensional virtual histology is a volume rendering of these structures of interest, which currently includes the bone, soft tissues and air spaces of the temporal bone; the maculae of utricle and saccule, otolith, ampullae, and the ossicles. The three-dimensional volume rendering imaging can be sliced open at any section and the appropriate raw radiological image superimposed on the cleavage plane. The images stack can be resected in any arbitrary plane. This virtual histological technique is a powerful investigating tool for studying the complex anatomy of the vestibular end-organs of living subjects. We can research morphological conditions of the vestibular end-organs of normal functional status and pathological conditions like a retinal camera.

To observe the function of the otolithic end organs and their input pathways in sudden sensorineural hearing loss (SSHL) patients.Forty cases of unilateral SSHL were enrolled as the observing group from May, 2011 to May, 2012. Thirty age- and gender-matched normal subjects were recruited as the control group. Both patients and normal subjects underwent conventional air-conducted ocular vestibular evoked myogenic potential (oVEMP) and cervical vestibular evoked myogenic potential (cVEMP) in bilateral ears. The results were compared between the affected ears, the contralateral ears and the normal controls.Overall, oVEMP was elicited in 16 affected ears (40.0%), 23 contralateral ears (57.5%) and 43 normal ears (71.7%). cVEMP could be elicited in 25 affected ears (62.5%), 30 contralateral ears (75.0%) and 49 normal ears (81.7%) respectively. Significant statistical significance could be found in the oVEMP response rate between the affected ears and the normal ears (χ(2) = 9.949, P = 0.002) and in the cVEMP response rate between the affected ears and the normal ears (χ(2) = 4.582, P = 0.032). Significant statistical difference could not be found in all oVEMP and cVEMP parameters (threshold, N1 latency, P1 latency, latency interval and amplitude) among groups (P0.05).The otolithic vestibular end organs and their input pathways could be damaged in SSHL patients. Such damages could be monitored objectively by cVEMP and oVEMP examinations.