Blog Archives

The cochleovestibular nerve identified during auditory brainstem implantation in patients with narrow internal auditory canals: Can preoperative evaluation predict cochleovestibular nerve deficiency?

Conclusions:
Visualization on MRI and detection of auditory responses suggested the presence of a CVN in patients with narrow IACs; however, the possibility of the presence of a CVN should be considered even when there is no clear evidence of a CVN on preoperative evaluations. Therefore, physicians should be prudent when determining candidacy for cochlear implantation or auditory brainstem implantation in patients with narrow IACs.

from The Laryngoscope

Regional cortical thickness and cognitive functions in non-demented Parkinson’s disease patients: a pilot study

Conclusions:  Cognitive and cortical changes in non-demented patients with PD are detectable and clearly related.

from the European Journal of Neurology

Speech and MRI Results Following Autologous Fat Transplantation to the Velopharynx in Patients With Velopharyngeal Insufficiency.

Conclusions: Autologous fat transplantation to the velopharynx resulted in a significant reduction of the velopharyngeal distance and the velopharyngeal gap area during phonation, as measured by MRI. This was in accordance with a significant improvement in nasal turbulence. However, hypernasality and audible nasal emission did not change significantly and could not be correlated to the MRI findings.

from the Cleft Palate-Craniofacial Journal

The bony cochlear nerve canal in children with absent or hypoplastic cochlear nerves

BCNC is an additional parameter to assess presence of the cochlear branch of the CN. Presence of the BCNC may indicate cochlear nerve presence. Caution should be used in assessing candidacy of cochlear implants based on MRI alone and a combination of imaging and audiological tests should be used to assess presence of the CN.

from the International Journal of Pediatric Otorhinolaryngology

Diffusion tensor imaging of the hippocampus and verbal memory performance: The RUN DMC Study

Conclusion: Microstructural integrity of the hippocampus assessed by DTI is related to verbal memory performance in elderly with SVD, also in participants with an intact appearing hippocampus. Changes in hippocampal microstructure may be an early marker of underlying neurodegenerative disease, before macrostructural (i.e., volumetric) changes occur.

from Human Brain Mapping

Temporal bone abnormalities in children with GJB2 mutations

Conclusions:
Our study of 113 biallelic GJB2 patients with SNHL and temporal bone imaging is the largest study to date. We found only 10% had any abnormalities, most subtle, and none had EVA. Additionally, there was no correlation between SNHL severity and presence/absence/type of malformations or genotype. Disparities between our group and previous reports may be due to differences in degree of hearing loss, types of mutations, populations studied, and radiologic factors for both image acquisition and interpretation.

from The Laryngoscope

MRI Anatomical and Morphological Differences in the Vocal Tract Between Dysphonic and Normal Adult Women

Results obtained from this study suggest that patients with VN may present a constantly increased tension of the laryngeal muscles, even at rest; moreover, reduced anterior-posterior dimension of the larynx may be a morphological characteristic of patients with VN.

from the Journal of Voice

Accuracy of 3.0 Tesla magnetic resonance imaging in the diagnosis of intracochlear schwannoma

Intracochlear schwannomas (ICSs) are rare tumors. The diagnosis of ICS is based on high-resolution magnetic resonance imaging (MRI), which should be used for the accurate determination of the location of tumors. Recent advancements in imaging technologies and software enable the precise regional diagnosis of ICS. We experienced a case of intracochlear schwannoma with a diagnosis of progressive hearing loss and tinnitus. Audiometry revealed severe hearing loss in the right ear with remaining low-frequency hearing. MRI showed an abnormal lesion in the cochlea. Three-dimensional real inversion recovery (3D rIR) and constructive interference in steady state (CISS) MRI revealed the size and shape of the tumor via identification of the cochlear nerve and cochlear fluid space. CISS and 3D rIR sequences provide useful information regarding the boundaries of tumors and the tissues that surround them.

from Auris Nasus Larynx

Morphological Cerebral Correlatesof CERAD Test Performance in Mild Cognitive Impairment and Alzheimer’s Disease

The objective of this study was to investigate the associations between structural cerebral changes and neuropsychological deficits in mild cognitive impairment (MCI) and Alzheimer’s disease (AD). Sixty patients with MCI, 34 patients with mild to moderate AD, and 32 healthy controls underwent both extensive neuropsychological assessment (CERAD test battery) and high-resolution structural magnetic resonance imaging. We used optimized voxel based morphometry to investigate (i) differences in gray matter density between the three aforementioned groups and (ii) the putative relations of CERAD test performance with atrophic brain changes. When compared to the healthy controls, the AD patients and, to a lesser extent, patients with MCI showed significant density losses predominantly in the medial temporal lobe. Deficits in verbal fluency and word finding were significantly correlated with left fronto-temporal and left temporal (including the hippocampus) changes, respectively. Decreased scores in immediate and delayed recall and in delayed recognition were associated with several cortical and subcortical sites including the parahippocampal and posterior cinguli gyri, the right thalamus, and the right hippocampus, whereas deficits in constructional praxis and constructional praxis recall referred to sites in the left thalamus and cerebellum, and the temporal cortices (bilaterally), respectively. Our findings lend further support for medial temporal lobe degeneration in MCI and AD and demonstrate that cognitive deficits as assessed on the CERAD do not simply refer to specific changes in discrete cerebral sites but rather reflect morphological alterations in widespread networks.

from the Journal of Alzheimer’s Disease

Vestibular schwannoma: role of conservative management

Two-thirds of vestibular schwannomas did not grow. Radiological surveillance is an acceptable approach in carefully selected patients. Once a sporadic vestibular schwannoma reaches 2 cm in intracranial diameter, it is likely to continue growing. We do not recommend conservative management for sporadic tumours with an intracranial diameter of 1.5 cm or more. Vestibular schwannoma management is more complex in patients with neurofibromatosis type two.

from the Journal of Laryngology and Otology

Vestibular schwannoma: when to look for it?

As regards vestibular schwannoma screening protocols, the best compromise between sensitivity and screening rate was offered by a criterion comprising either: (1) ≥20 dB asymmetry at two neighbouring frequencies, or unilateral tinnitus, or (2) ≥15 dB asymmetry at two frequencies between 2 and 8 kHz.

from the Journal of Laryngology and Otology

Spatial Distribution of Deep Sulcal Landmarks and Hemispherical Asymmetry on the Cortical Surface

The locally deepest regions of major sulci, the sulcal pits, are thought to be the first cortical folds to develop and are closely related to functional areas. We examined the spatial distribution of sulcal pits across the entire cortical region, and assessed the hemispheric asymmetry in their frequency and distribution in a large group of normal adult brains. We automatically extracted sulcal pits from magnetic resonance imaging data using surface-based methods and constructed a group map from 148 subjects. The spatial distribution of the sulcal pits was relatively invariant between individuals, showing high frequency and density in specific focal areas. The left and right sulcal pits were spatially covariant in the regions of the earliest developed sulci. The sulcal pits with great spatial invariance appear to be useful as stable anatomical landmarks. We showed the most significant asymmetry in the frequency and spatial variance of sulcal pits in the superior temporal sulcus, which might be related to the lateralization of language function to the left hemisphere, developing more consistently and strongly than for the right. Our analyses support previous empirical and theoretical studies, and provide additional insights concerning the anatomical and functional development of the brain.

from Cerebral Cortex

A Bivariate Twin Study of Regional Brain Volumes and Verbal and Nonverbal Intellectual Skills During Childhood and Adolescence

Twin studies indicate that both intelligence and brain structure are moderately to highly heritable. Recent bivariate studies of adult twins also suggest that intelligence and brain morphometry are influenced by shared genetic factors. The current study examines shared genetic and environmental factors between brain morphometry and intelligence in a sample of children and adolescents (twins, twin siblings, and singletons; n = 649, ages 4–19). To extend previous studies, brain morphometric data were parsed into subregions (lobar gray/white matter volumes, caudate nucleus, lateral ventricles) and intelligence into verbal and nonverbal skills (Wechsler Vocabulary and Block Design subtests). Phenotypic relationships between brain volumes and intelligence were small. Verbal skills shared unique environmental effects with gray matter volumes while nonverbal skills shared genetic effects with both global and regional gray and white matter. These results suggest that distinct mechanisms contribute to the small phenotypic relationships between brain volumes and verbal versus nonverbal intelligence.

from Behavior Genetics

Comparison between Logopedic and MRI Findings in Evaluating Tongue Function

Results: We observed marked differences between the logopedic and MRI findings, yet there were no significant correlations between the logopedic outcome and distances measured via MRI in tongue resting position and swallowing patterns.
Conclusion: We noted little concordance between logopedic findings according to Kittel and MRI analysis according to Fujiki et al. Which of these findings correctly reflects the actual clinical situation remains unclear.

from

Structural Analysis of Heschl’s Gyrus in Schizophrenia Patients with Auditory Hallucinations

Background/Aims: Heschl’s gyrus (HG) is functionally involved in the genesis of auditory verbal hallucinations (AVH). This dysfunction seems to be structurally facilitated. The aim of the study was to analyze macrostructural features of HG in a group of patients reporting AVH who demonstrated white matter diffusion tensor imaging abnormalities reported previously. Methods: 3-D anatomical MR scans were obtained (patients with and without history of AVH, controls). HG was delineated by manual segmentation. Cortical folding, absolute and relative volumes, laterality were analyzed. Results: According to the literature, in the collapsed group of patients, the normal left-greater-than-right laterality of HG was attenuated. We found a trend towards a higher number of duplicated HG in hallucinating patients. We also found a bigger volume of HG in the right hemisphere in hallucinating patients. This effect was caused by gray and white matter increase. Conclusions: This is the first study on manual volumetry of HG in a group of schizophrenia patients with AVH compared to patients without AVH. In a previous analysis of the diffusion tensor imaging data of the here presented sample, we found higher directionality of the arcuate fasciculus in patients with AVH, facilitating abnormal co-activation in the auditory cortices in the hallucinating brain. As these abnormal activations are frequent in hallucinating patients, the here described volume increase of HG might be interpreted as compensatory plastic adaptations of the contralateral regions. We suggest that this volume increase of HG is caused by the symptomatology and not by the underlying disorder of schizophrenia.

from Neuropsychology