Correlation of computed tomography with histopathology in otosclerosis.

OBJECTIVE: Until now, the use of computed tomography (CT) in the diagnosis and evaluation of otosclerosis has been based on correlation of radiologic findings to patient histories, intraoperative examinations, and audiologic data. The purpose of this study was to compare CT findings in otosclerosis to histopathology. STUDY DESIGN: Prospective blinded. SETTING: Radiology department in a tertiary referral hospital and otopathology laboratory. PATIENTS: Temporal bones from patients with otosclerosis and other otologic diseases (used as controls). INTERVENTION(S): Blinded review of specimen CT scans by radiologists and comparison of CT findings to histopathology of the same bones. MAIN OUTCOME MEASURE(S): Ability of CT to diagnose otosclerosis, identify otosclerotic foci in defined zones of the otic capsule, determine endosteal layer involvement, oval window (OW) obliteration, and round window (RW) obliteration. RESULTS: In a randomized blinded evaluation, radiologists identified 8 of 10 bones with otosclerosis and made 3 false-positive diagnoses from the 36 control bones. Radiologic examination correctly identified otosclerosis anterior to the oval window, in the pericochlear area, and in the round window niche in 17 of 17, 9 of 11, and 3 of 6 bones, respectively. CT correctly determined involvement of the endosteal layer, OW obliteration, and RW obliteration in 5 of 8, 2 of 2, and 2 of 2 temporal bones. CONCLUSION: High-resolution CT is highly sensitive and specific for the diagnosis of otosclerosis when compared with histopathology. Very small and subtle otosclerotic foci seen on pathology may be missed on CT. Although CT was able to positively identify cochlear endosteal margin involvement, the false-negative rate on CT was significant.

The asymmetric gait toenail unit sign.

The aim of this investigation was to resolve a diagnostic problem and report toenail unit changes attributable to shoe friction that resemble onychomycosis, but that are fungus-negative, and identify common skeletal causes in patients with an asymmetric walking gait. X-ray and clinical feet inspections were performed to evaluate skeletal components that change normal foot biodynamics. Forty-nine patients, all dermatophyte-negative, were reviewed. All patients were those seen in our private practice who demonstrated skeletal and toenail unit abnormalities such as onycholysis, nail bed keratosis resembling distal subungual onychomycosis, nail plate surface abnormalities, distal toe skin keratosis, a diagnostic nail plate shape, as well as several skeletal abnormalities. The clinical abnormalities of the asymmetric gait syndrome include onycholysis, nail bed keratosis, nail plate surface abnormalities, and a diagnostic nail plate shape. By the patient's history, the skeletal findings that were present worsened with age and, in many patients, they were familial. Onychomycosis does not lead to an asymmetric gait nail problem, asymmetric gait toenail does not favor dermatophyte infection, and not all nail dystrophies are the result of an asymmetric walking gait.

Volumetric and visual rating of magnetic resonance imaging scans in the diagnosis of amnestic mild cognitive impairment and Alzheimer's disease.

BACKGROUND: In the diagnosis of Alzheimer's disease (AD), structural magnetic resonance imaging (MRI) scans have been used primarily to exclude non-Alzheimer's causes of dementia. However, the pattern and the extent of medial temporal atrophy on structural MRI scans, which correlate strongly with the pathological severity of AD, can be used to support the diagnosis of a degenerative dementia, especially AD, even in its early predementia stage. METHODS: Elderly subjects (n = 224) were diagnosed with either no cognitive impairment (NCI), amnestic mild cognitive impairment (aMCI), or AD. Hippocampal and hemispheric gray matter volumes were measured on structural MRI scans, and a new visual rating system was used to score the severity of medial temporal atrophy (VRS-MTA) of the hippocampus (HPC), entorhinal cortex, and perirhinal cortex on a coronal image intersecting the mammillary bodies. RESULTS: Although both VRS-MTA scores and HPC volumes distinguished between subjects with NCI, aMCI, and AD, subjects with aMCI and NCI could be better distinguished using right VRS-MTA scores, in comparison with right HPC volumes. VRS-MTA scores were more highly correlated with episodic memory and Clinical Dementia Rating scores. A combination of left sided VRS-MTA scores and left sided hippocampal volume was the most predictive measure of diagnostic classification. CONCLUSION: VRS-MTA is a clinically convenient method or distinguishing aMCI or AD from NCI. As compared with volumetric measures, it provides better discriminatory power and correlates more strongly with memory and functional scores.

Reliability and validity of an algorithm for the diagnosis of normal cognition, mild cognitive impairment, and dementia: implications for multicenter research studies.

BACKGROUND: The traditional consensus diagnosis (ConsDx) of normal cognition, mild cognitive impairment (MCI), and dementia relies on the reconciliation of an informant-based report of cognitive and functional impairment by a physician diagnosis (PhyDx), and a neuropsychological diagnosis (NPDx). As this procedure may be labor intensive and influenced by the philosophy and biases of a clinician, the diagnostic algorithm (AlgDx) was developed to identify individuals as cognitively normal, with MCI, or dementia. METHODS: The AlgDx combines the PhyDx with the NPDx, using a diagnostic algorithm that provides cognitive diagnoses, as defined by the National Alzheimer Coordinating Center/Uniform Data Set nomenclature. Reliability of the AlgDx was assessed in 532 community-dwelling elderly subjects by its concordance with the ConsDx and association with two biomarkers, medial temporal atrophy (MTA) scores of brain magnetic resonance imaging scans, and Apolipoprotein E (ApoE)-epsilon4 genotype. RESULTS: A high degree of concordance was observed between ConsDx and AlgDx with a weighted Cohen's kappa of 0.84. Concordance of the AlgDx to the same ConsDx categories ranged from 85% to 92%. Excellent discriminative validity was observed using AlgDx, MTA scores, and ApoE-epsilon4 allele frequencies, each of which distinguished subjects with amnestic MCI and dementia from normal subjects. CONCLUSION: The AlgDx of normal cognition, MCI, and dementia is a valid alternative that reduces time, effort, and biases associated with the ConsDx. The inherent reliability of a fixed algorithm, together with its efficiency and avoidance of individual bias, suggests the AlgDx may be used in longitudinal, multisite clinical trials, and population studies of MCI and dementia.

A comparative analysis of structural brain MRI in the diagnosis of Alzheimer's disease.

Dementia is a debilitating and life-altering disease which leads to both memory impairment and decline of normal executive functioning. While causes of dementia are numerous and varied, the leading cause among patients 60 years and older is Alzheimer's disease. The gold standard for Alzheimer's diagnosis remains histological identification of amyloid plaques and neurofibrillary tangles within the medial temporal lobe, more specifically the entorhinal cortex and hippocampus. Although no definitive cure for Alzheimer's disease currently exists, there are treatments targeted at preserving cognition and memory while delaying continued loss of function. Alzheimer's disease exists along a spectrum of cognitive decline and is often preceded by Mild Cognitive Impairment (MCI). Patients with MCI demonstrate memory loss and cognitive impairment while still continuing normal activities of daily living, and are considered to be at increased risk for developing Alzheimer's Dementia. Identifying patients with prodromal states of Alzheimer's dementia such as MCI may allow initiation of appropriate treatment planning and delay of cognitive decline. Therefore, the need for a non-invasive early biomarker for the detection of Alzheimer's disease has never been greater. Multiple neuroimaging methods utilizing visual rating scales, volumetric measurements, and automated methods have been developed to identify, quantify, and track anatomic sequelae of Alzheimer's Disease.

Visual rating system for assessing magnetic resonance images: a tool in the diagnosis of mild cognitive impairment and Alzheimer disease.

OBJECTIVE: Subjects with mild cognitive impairment (MCI) and mild Alzheimer disease (AD) can be distinguished from elderly subjects with no cognitive impairment (NCI) by the degree of atrophy in the entorhinal cortex (ERC) and the hippocampus (HPC), quantified by volumetric magnetic resonance image (MRI) studies. Because volumetric MRI requires rigorous standards for image acquisition and analysis and is not suitable for routine clinical use, we have used calibrated visual rating to measure atrophy in the ERC, HPC, and perirhinal cortex (PRC) and evaluated its utility in the diagnosis of very early AD. METHODS: Thus far, visual rating methods, which have been found to be reliable and sensitive only for measurement of atrophy of the HPC or for the entire medial temporal region, have been found to be relatively insensitive for discriminating mild AD from elderly NCI subjects. We have developed a computer-based visual rating system (VRS) using reference images for calibration of atrophy ratings in several discrete brain regions, including the ERC, HPC, and PRC. The VRS reference images facilitate training of raters and promote standardization of all atrophy ratings. Interrater and intrarater reliability measurements were assessed; subsequently, the ability of VRS to discriminate the diagnoses among 73 elderly subjects was studied (NCI = 27, MCI = 23, and AD = 23). RESULTS: Kappa values for interrater reliability of the ERC, HPC, and PRC were between 0.75 and 0.94, and for intrarater reliability, they were between 0.84 and 0.93, indicating that VRS enables highly reliable ratings to be obtained. Atrophy ratings in the ERC, HPC, and PRC distinguished AD from NCI subjects but did not distinguish AD from MCI subjects who tended to have intermediate levels of atrophy. Right and left ERC ratings and the right HPC rating distinguished MCI from NCI subjects. CONCLUSIONS: The visual rating system is the first semiquantitative method that enables reliable measurements of ERC atrophy, and ERC measurement was found to be the best discriminator between MCI and NCI subjects. Visual rating system is a user-friendly tool that can allow a radiologist or a clinician to use structural MRI scans to be used as a biomarker in the diagnosis of prodromal AD.

Transient band-like keratopathy after treatment for seborrheic dermatitis.

PURPOSE: To describe a case of transient band-like keratopathy after ocular exposure to fluocinonide cream and ketoconazole shampoo. DESIGN: Observational case report. RESULTS: A 40-year-old patient presented with acute pain, photophobia, lacrimation, and redness in 1 eye. The symptoms began while using fluocinonide cream and ketoconazole shampoo as treatment of seborrheic dermatitis of the scalp. Examination revealed white clumpy deposits in a horizontal band across the inferocentral corneal epithelium and conjunctival hyperemia. Corneal scrapings revealed no cells or organisms, and culture was negative. The lipophilic deposits dissolved during slide fixation and processing. With conservative treatment the deposits resolved in 3 days. CONCLUSION: We present a case of transient band-like corneal deposit, a novel complication of fluocinonide and ketoconazole exposure.