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Conclusions: EABR is a reliable and effective way of objectively confirming device function and implant-responsiveness of the peripheral auditory neurons up to the level of the brainstem in cases of inner ear malformation. Objective: To investigate the usefulness of measuring the intra-operative electrically evoked compound action potential (ECAP) and electrically evoked auditory brainstem response (EABR) in patients with and without congenital inner ear anomalies during cochlear implantation. Method: Thirty-eight consecutive children (40 ears) aged 5 or younger with congenital profound hearing loss. Twenty-four (25 ears) lacked congenital inner ear anomalies. The 14 patients (15 ears) with a malformation had common cavities (four ears), incomplete partition type I (three ears), cochlea hypoplasia type III (three ears), enlarged vestibular aqueduct (four ears), and cochlear nerve canal stenosis (one ear). Main outcome measures are ECAP and EABR responses. Results: Of the 25 ears lacking any malformation, 21, three, and one showed ‘Good’, ‘Variable’, and ‘No’ ECAP responses, respectively, and 24 and one showed ‘Good’ and ‘Variable’ intra-cochlear responses, respectively. Of the 15 ears with a malformation, two showed ‘Good’ ECAP responses, nine had ‘Variable’ ECAP responses, and four showed ‘No’ ECAP responses. Moreover, five showed ‘Good’ EABR responses and 10 showed ‘Variable’ EABR responses.  相似文献   
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ObjectiveEosinophilic otitis media (EOM) is an intractable type of otitis media in which sensorineural hearing loss (SNHL) progresses over time. Clinically, bacterial infection complicates the course of EOM, making it challenging to control otorrhea/middle ear effusion (MEE) from infected ears, and accelerates the progression of SNHL. In this study, we focused on infection, one of the risk factors for SNHL in EOM, and analyzed factors associated with it.MethodsIn this cohort study, we evaluated 144 ears of 72 patients diagnosed with bilateral EOM. Patients visited our hospital once every 1–3 months and received intratympanic or systematic administration of steroids when otorrhea/MEE was observed. Several investigations, including blood tests, otorrhea/MEE cytology, bacterial culture tests, and respiratory function tests, were performed. In the otorrhea/MEE cytology, the leukocyte fraction was measured.ResultsTwo risk factors for SNHL in EOM were middle ear mucosal thickening (p <0.01) and infection (p <0.05). Compared to the group with <40% neutrophils in otorrhea/MEE samples, groups with 40–70% and ≥70% neutrophils had a significantly higher bone conduction hearing level (p <0.01, p <0.05, respectively). Two risk factors associated with the occurrence of infection in EOM were tympanic membrane (TM) perforation (p <0.01) and the coincidence of otorrhea/MEE and rhinorrhea in bacterial culture test results (p <0.001). A positive correlation was observed between TM perforation and infection (p <0.001). Our analysis of the relationship between the frequency of intratympanic corticosteroids administration and the time-period until the occurrence of TM perforation showed that >4 intratympanic administrations/year significantly increased the risk of perforation (p<0.001). Pseudomonas aeruginosa was isolated from otorrhea/MEE samples, while Pseudomonas aeruginosa and fungi, detected in cultures of rhinorrhea samples, were significantly related to the deterioration of bone conduction hearing levels.ConclusionThe risk factors associated with the occurrence of infection in patients with EOM were TM perforation and the coincidence of otorrhea/MEE and rhinorrhea in bacterial culture test results. Since TM perforation is likely to occur even due to intratympanic corticosteroids administration, it is necessary to confirm whether the frequency of treatment is appropriate and try a less invasive technique of administration. Furthermore, Pseudomonas aeruginosa infection poses a high risk for the development of SNHL, and clinicians should be alert to this possibility, even if the bacteria were identified only in cultures of rhinorrhea samples.  相似文献   
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Bone scintigraphy (BS) of disseminated skeletal metastasis is sometimes misinterpreted as normal. The use of computer-assisted diagnosis (CAD) may resolve this problem. We investigated the performance of a CAD system, BONENAVI, in the diagnosis of disseminated skeletal metastasis. Cases of disseminated skeletal metastasis were selected from a BS log. These patients’ BSs were analyzed by BONENAVI to obtain an artificial neural network (ANN) and bone scan index (BSI). Clinical features (type of primary cancer, CT type, and BS type) were compared with the BONENAVI (ANN and BSI) results. The BS findings (diffuse increased axial skeleton uptake, inhomogeneity of uptake, proximal extremity contrast, and degree of renal uptake) and ANN or BSI were evaluated. Then, negative ANN patients were presented. Fifty-four patients were diagnosed as having disseminated skeletal metastasis. Regarding the primary cancers, 12 had prostate cancer, 16 gastric cancers, 16 breast cancers, and 10 miscellaneous cancers. Total sensitivity of ANN (≥ 0.5) was 76% (41/54). ANN values correlated with the BS type among clinical features. Diffuse increased axial skeleton uptake was mostly correlated with ANN of the BS findings. The BONENAVI CAD system was partially helpful in diagnosing disseminated skeletal metastasis, but the sensitivity of BONENAVI was not sufficient and underestimated the disseminated skeletal metastasis. Further improvement of this CAD system is necessary to improve the detectability of disseminated skeletal metastasis.  相似文献   
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PurposeNon-calcified cholesterol stones that are small in size are hard to be depicted on CT or magnetic resonance cholangiopancreatography. This institutional review board (IRB)-approved retrospective in vitro study aims to characterize contrast behaviors of 3 main components of the gallstones, i.e., cholesterol component (CC), bilirubin calcium component (BC) and CaCO3 (CO) on 3D radial scan with ultrashort TE (UTE) MRI, and to test the capability of depicting CC of gallstones as bright signals as compared to background saline.MethodsFourteen representative gallstones from 14 patients, including 15 CC, 6 BC and 4 CO, were enrolled. The gallstones underwent MRI including fat-saturated T1-weighted image (fs-T1WI) and UTE MRI with dual echoes. The contrast-to-noise ratio (CNR) and the chemical analysis for the 25 portions of the stones were compared.ResultsBC was bright on fs-T1WI, which did not change dramatically on UTE MRI and the signal did not remain on UTE subtraction image between dual echoes. Whereas the CC was negative or faintly positive signal on fs-T1WI, bright signal on UTE MRI and the contrast remained even higher on the UTE subtraction, which reflected their short T2 values. Median CNRs and standard errors of the segments on each imaging were as follows: on fs-T1WI, −10.2 ± 4.2 for CC, 149.7 ± 27.6 for BC and 37.9 ± 14.3 for CO; on UTE MRI first echo, 16.7 ± 3.3 for CC, 74.9 ± 21.3 for BC and 17.7 ± 8.4 for CO; on UTE subtraction image, 30.2 ±2.0 for CC, −11.2 ± 5.4 for BC and 17.8 ± 10.7 for CO. Linear correlations between CNRs and cholesterol concentrations were observed on fs-T1WI with r = −0.885, (P < 0.0001), UTE MRI first echo r = −0.524 (P = 0.0072) and UTE subtraction with r = 0.598 (P = 0.0016).ConclusionUTE MRI and UTE subtraction can depict CC bright.  相似文献   
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