The relationship between jugular bulb position and jugular bulb related inner ear dehiscence: a retrospective analysis.

OBJECTIVE: High jugular bulb (HJB) can erode inner ear structures creating a jugular bulb related inner ear dehiscence (JBID). The aim of this study was to analyze the relationship between the position of jugular bulb (JB) and JBID using high-resolution computed tomography (HRCT). MATERIAL AND METHODS: In this retrospective study HRCT images of 552 ears of 276 patients with hearing loss, otogenic vertigo, tinnitus or idiopathic peripheral facial nerve paralysis were analyzed. HJB type-1 was defined when JB dome reached above the inferior part of the round window, but was below the inferior edge of the internal acoustic meatus (IAM). HJB type-2 was defined when the dome of JB was higher than the inferior edge of IAM. The frequencies and types of HJB were evaluated. JBID for each HJB type was determined. Frequencies of JBID eroding the vestibular aqueduct (VA), the cochlear aqueduct and the posterior semicircular canal were examined. RESULTS: HJB type-1 and HJB type-2 were found in 19% (105/552) and in 15.8% (87/552) of studied ears. JBID showed to be in 3.8% (21/552) of all ears. 90.5% (19/21) of JBID revealed eroding of VA. Jugular bulb related cochlear aqueduct dehiscence and jugular bulb related posterior semicircular canal dehiscence were found in one ear each. The frequency of jugular bulb related vestibular aqueduct dehiscence (JBVAD) in patients with HJB reaching above IAM was higher than in patients with HJB lower than IAM. CONCLUSIONS: HJB is common, but JBID is rare. JBID prevalently erodes VA. HJB rising above IAM is most at risk to show JBVAD.

Promontory electrical stimulation to elicit vestibular evoked myogenic potentials (VEMPs).

CONCLUSION: Vestibular evoked myogenic potentials (VEMPs) provoked electrically at the promontory provide a feasible method to record vestibular responses in awake patients. OBJECTIVES: Electrically evoked VEMP testing has been performed by galvanic stimulation at the mastoid so far. The present study examined an electrical stimulation mode close to the otolith organs at the promontory. METHODS: Fourteen cochlear implant candidates who were planned for clinical routine promontory stimulation testing (PST) to assess auditory nerve function underwent promontory VEMP testing. After testing the cochlear nerve function during PST promontory cervical VEMPs (p-c-VEMPs) and promontory ocular VEMPs (p-o-VEMPs) were recorded during subsequent transtympanic electrical stimulation at the promontory. RESULTS: Promontory VEMP testing was well tolerated by the patients. Mean latencies for p-c-VEMPs were 10.30 ± 2.23 ms (p1) and 17.86 ± 3.83 ms (n1). Mean latencies for p-o-VEMPs were 7.64 ± 1.24 ms (n1) and 11.2 ± 1.81 ms (p1). The stimulation threshold level was measured at 0.15 ± 0.07 mA for p-c-VEMPs and at 0.19 ± 0.11 mA for p-o-VEMPs. The discomfort level was found to be at 0.78 ± 0.29 mA for p-c-VEMPs and at 0.69 ± 0.25 mA for p-oVEMPs. Mean p1-n1 amplitude in p-c-VEMPs was 124.78 ± 56.55 µV and p-o-VEMPs showed a mean n1-p1 amplitude of 30.94 ± 18.98 µV.

Jugular bulb abnormalities in patients with Meniere's disease using high-resolution computed tomography.

Temporal bone abnormalities such as hypoplasia of the vestibular aqueduct or hypopneumatization of the mastoid have been described in Meniere's disease (MD). Jugular bulb abnormalities (JBA) are one of the most common temporal bone abnormalities. The aim of this study was to evaluate the frequency of JBA in MD. Radiological data obtained by temporal bone high-resolution computed tomography of 200 ears of 167 MD patients (MD group) and 218 ears of 109 patients with normal inner ear function (control group) were analyzed retrospectively. The frequencies of high jugular bulb (HJB), jugular bulb diverticulum (JBD), inner ear adjacent jugular bulb (IAJB) and jugular bulb related inner ear dehiscence (JBID) were evaluated and compared between MD group and control group. IAJB was differentiated into vestibular aqueduct adjacent jugular bulb (VAAJB), cochlear aqueduct adjacent jugular bulb and posterior semicircular canal adjacent jugular bulb. JBID was further analyzed by differentiating into jugular bulb related vestibular aqueduct dehiscence (JBVAD), jugular bulb related cochlear aqueduct dehiscence and jugular bulb related posterior semicircular canal dehiscence. The frequencies of HJB, JBD and IAJB were higher in MD group compared to control group (21, 13.3 %, p = 0.036; 8.5, 3.7 %, p = 0.037; 13.5, 4.6 %, p = 0.001). No differences between both groups were seen in JBID (4.0, 2.3 %, p = 0.315). Most IAJB and JBID were seen in VAAJB and JBVAD. There is a higher frequency of JBA in patients with MD than in patients without inner ear symptoms. Temporal bones of MD patients might be constituted anatomically different, carrying predisposing factors for the development of clinically apparent MD.

Radiological findings of the cochlear aqueduct in patients with Meniere's disease using high-resolution CT and high-resolution MRI.

The objective of the present study was to evaluate the cochlear aqueduct (CA) in Meniere's disease (MD) and to disclose radiological differences of CA between MD and non-MD patients by means of high-resolution computed tomography (HRCT) and high-resolution magnetic resonance imaging (HRMRI). Radiological data of 86 ears of MD patients which were separated into 52 ears of diseased side group (MD-D group) and 34 ears of contralateral non-affected side group of unilateral MD (MD-ND group), 27 ears of patients with sensorineural hearing loss (SNHL group) and 56 ears of patients with somatoform dizziness and normal hearing (control group) were analyzed retrospectively. The bony type of CA, the bony length of CA, and the bony width of CA medial orifice was measured in HRCT. The visibility of CA in HRMRI was scored. Fluid length in CA and fluid width in medial orifice were measured in HRMRI. Data were compared between MD-D, MD-ND, SNHL, and control group. There were no significant differences in the bony type of CA, bony length of CA, bony width of CA medial orifice, and fluid width of CA medial orifice between MD-D, MD-ND, SNHL and control group (p > 0.05). However, CA fluid length of MD-D (5.13 ± 1.88 mm) and of MD-ND group (5.44 ± 1.81 mm) was significantly shorter than fluid length of SNHL (6.90 ± 1.55 mm) (p < 0.001, p = 0.001) and of control group (7.43 ± 1.24 mm) (p < 0.001, p < 0.001). The ratio between CA fluid length and CA bony length was the smallest in MD-D group (0.403; p = 0.009). CA bony dimensions of affected ears of MD are normal, but CA fluid length is decreased.

[Comparative analysis of 226 Hz and 1 000 Hz probe tone tympanometry in infants].

OBJECTIVE: To analyze the judgement standard and evaluate the diagnostic value of the low frequency and high frequency tympanometry in infants with otitis media. METHOD: Tympanograms for admittance with 226 Hz and 1 000 Hz probe tones and resonant frequency were obtained from normal infants (195 cases, 321 ears) and infants with otitis media(122 cases, 171 ears). The mean, standard deviation, median, 5% quantile, 95% quantile and 95% confidence interval of peak admittance, gradient and resonant frequency were measured and calculated in different age groups. The significant differences of 1000 Hz peak admittance, 226 Hz peak admittance and gradient between normal infants and infants with otitis median were analyzed using SPSS 11.0. The false positive rate and the false negative rate of different age groups in infants with otitis media were evaluated according to such judgement standards as 1000 Hz peak admittance, 226Hz peak admittance or gradient. RESULT: The false positive rate and the false negative rate of the 1000 Hz probe tone tympanometry in infants with otitis media unter one year of age were 3.07% and 1.84% as the normal range of positive peak was more than 0.2 mmho. The false positive rate and the false negative rate of the 1000 Hz probe tone tympanometry in infants with otitis media aged 1-2 years and aged 2-3 years were 3.26%, 5.26% and 1.52%, 0.00% respectively,as the normal range of positive peak was more than 0.3 mmho. These was no significant difference in the gradient with 226 Hz probe tone between normal infants and infants with otitis median under one year of age. The false positive rate and the false negative rate of the 226 Hz probe tone tympanometry in infants with otitis media aged 1-2 years and aged 2-3 years were 44.57%, 31.58% and 16.67%, 6.67% respectively, as the gradient with 226 Hz probe tone was a judgement standard. CONCLUSION: (1) The diagnostic accuracy of tympanometry with 1000 Hz probe tone for otitis media in infants younger than 3 years of age exceeded 226 Hz probe tone tympanometry, the 1000 Hz probe tone tympanometry is suggested to the evaluation of middle ear function in infants before 3 years. (2) It is reasonable that the normal range of positive peak is more than 0.2 mmho in infants unter one year of age and the normal range of positive peak is more than 0.3 mmho in infants aged 1-3 years.

[Serum allergen-specific IgE in patients with eosinophilic nasal polyps].

OBJECTIVE: To investigate the relationship between airborne allergen and patients with nasal polyps (NP). METHOD: Eighty-three cases of patients with NP were classified into the eosinophilic group(ENP) and non eosinophilic group (nENP) in terms of the EOS count in NP specimen, all patients underwent specific-IgE test with standardized allergens and the results were analyzed. RESULT: The specific-IgE positive rate was 59.26% in ENP group and 23.21% in the nENP group respectively (P < 0.01), and the positive rate of ENP was statistical significance compared with nENP. The dust mite was the most prevalent airborne allergen in ENP group. CONCLUSION: The perennial airborne allergens may play a certain role in the etiology and pathogenesis of NP.

[Construction of recombinant adenovirus and mediated reported gene expression in the guinea pig cochlea].

OBJECTIVE: To purify P0 protein from guinea pig's inner ear by preparative SDS-PAGE and study the possible role it may play in the etiology of autoimmune inner ear disease. METHOD: A mixture of membraneous proteins of inner ear was separated by preparative SDS-PAGE. The corresponding band at 30kd was cut and electrically eluted. The protein collected was identified by analytical SDS-PAGE and Western blot assay. A group of 20 guinea pigs were immunized with P0 protein emulsified in complete Freund's adjuvant, another 10 guinea pigs were immunized with complete Freund 's adjuvant only as control. The guinea pigs' hearing thresholds, serum IgG level and morphological changes in the inner ear were investigated. The distribution of P0 protein in the cochlear was detected by immunohistochemical technique. RESULT: The purity of the protein was demonstrated by a single band at the 30 kD site in SDS-PAGE, which was identified as P0 protein by western blot analysis assay. About 17.5% P0-immunized guinea pigs showed increased hearing thresholds, elevated IgG level (F =6.48, P <0. 01), as well as a decreased number of spiral ganglion cells and inflammatory cell infiltration in the cochlear nerve region. The P0 protein is distributed in the cochlear nerve and spiral ganglion only. CONCLUSION: P0 protein from guinea pig's inner ear can be successfully purified by preparative SDS-PAGE and an animal model of experimental autoimmune inner ear disease induced by P0 protein is successfully established.

[Follow-up examination for newborns and infants who failed hearing screening].

OBJECTIVE: To investigate the hearing change and the characteristic of hearing thresholds of the infants failing in the hearing screening. METHOD: ABR,DPOAE and acoustic immittance were used to test infants failing in the screening in their third month and the sixth month, whose results were compared. RESULT: In the third month the false positive rate of DPOAE test was 9.6%. Comparing with the results tested in the third month, the degree of severe hearing loss retested in the sixth month did not change much. But the percentage of the slight-moderate hearing loss improvement to normal or better was higher. Comparing ABR threshold result in the third month and that in the sixth month, t = 3.496, P <0.01 in the left ear, and t = 5.572, P <0.01 in the right ear, respectively. There was significant difference between these results. CONCLUSION: The new-borns failing DPOAE can not be just considered to identifying hearing loss,and it must be with the ABR to make the diagnosis. It is feasible to diagnose severe-profound hearing loss in the third month and interfere before the sixth month, but the infants with mild-moderate hearing loss must undertake the auditory tests more than twice and be followed up in more than half a year, then we can make diagnosis according to the audiologic evaluations results and the daily behaviors.