Hippocampal shrinkage is commonly reported in schizophrenia, but its role in the illness is still poorly understood. In particular, it is unclear how clinical and psychosocial variables relate to ...hippocampal volumes.
To investigate neuroanatomic differences in the hippocampus using three-dimensional (3D) computational image analysis.
We used high-resolution magnetic resonance imaging and surface-based modelling to map the 3D profile of hippocampal differences in adults with schizophrenia (n = 67) and a healthy control group (n = 72). Manual tracings were used to create 3D parametric mesh models of the hippocampus. Regression models were used to relate diagnostic measures to maps of radial distance, and colour-coded maps were generated to show the profile of associations.
There was no detectable difference between the schizophrenia and control groups in hippocampal radial distance. In the schizophrenia group, however, bilateral shape deflation was associated with greater illness severity (length of illness, positive and negative symptoms) and with poorer social functioning (educational level, quality of life and health status), which survived Bonferroni correction.
Illness severity and poor social functioning may be associated with hippocampal deflation in schizophrenia. As a structural sign of poor outcome, imaging measures might help to identify a subgroup of patients who may need specific treatment to resist hippocampal shrinkage, such as cognitive rehabilitation or physical exercise.
Abstract We describe the clinical findings and MRI features observed in a child who presented a two-step disease course: he was hypotonic at birth and soon afterwards developed seizures, which were ...partially responsive to treatment; he subsequently showed developmental delay and a progressive neurological deterioration with the onset of severe seizures at around three years of age. Head MRI at age 20 days was unremarkable, whereas at 25 months it showed bilateral hyperintensity of the deep cerebellar nuclei; five months later, the signal hyperintensity was also present in the cerebellar white matter and ventral pontine fibre tracts. Molecular analysis revealed a novel ACOX1 mutation, predicting a largely truncated protein. The white matter involvement, which followed an ascending trajectory from cerebellar and brainstem structures to the cerebral hemispheres, seemed to originate from the perinuclear white matter of the deep cerebellar nuclei.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Recently, mutations affecting different domains of dynamin-2 (DNM2) were associated alternatively with autosomal dominant centronuclear myopathy or dominant intermediate (demyelinating and axonal) ...Charcot-Marie-Tooth disease (CMT) type B.
To assess the etiologic role of DNM2 in CMT.
We performed a mutational screening of DNM2 exons 13 through 16 encoding the pleckstrin homology domain in a large series of CMT patients with a broad range of nerve conduction velocities and without mutations in more common genes.
We identified two novel DNM2 mutations that cosegregated with purely axonal CMT in two pedigrees without clinical evidence of primary myopathy.
Patients with axonal Charcot-Marie-Tooth disease type 2 neuropathy without mutations in more common genes should undergo investigation for DNM2 pleckstrin homology.
White matter lesions (WMLs) are commonly found on brain MRI of migraine patients. Migraine with aura (MA+) is associated with an increased frequency of right-to-left shunt (RLS) mostly due to patent ...foramen ovale. The relationship between WML load and RLS in MA+ is currently unknown.
MA+ patients were consecutively enrolled as part of the Shunt Associated Migraine (SAM) study. Patients underwent a standardized headache and vascular risk factors questionnaire, contrast-enhanced transcranial Doppler, blood coagulation tests, and brain MRI. RLS was categorized into four grades: no shunt, <10 microbubbles (mb), >10 mb single spikes pattern, and >10 mb shower/curtain pattern. Standard and fluid-attenuated inversion recovery T2-weighted MRI sequences were inspected for WMLs by three independent raters blinded to RLS grade. WML load was scored in the periventricular areas (PV-WMLs) with the Fazekas scale and in the deep white matter (D-WMLs) with the Scheltens scale. Interobserver agreement was good to excellent (kappa = 0.64 to 0.96, p < 0.0001). WML load was then correlated between patients with and without RLS.
One hundred eighty-five patients (77% women) were included. PV-WML load was similar between patients with and without RLS. D-WML load decreased in patients with RLS (p = 0.045). On logistic regression analysis, only age was associated with WMLs (p < 0.001).
The presence of right-to-left shunt does not increase white matter lesion load in patients who have migraine with aura.
Purpose
Bionic ear implants provide a solution for deafness. Patients treated with these hearing devices are often children who require close follow-up with frequent functional and radiological ...examinations; in particular, multislice computed tomography (MSCT). Dental volumetric cone-beam CT (CBCT) has been reported as a reliable technique for acquiring images of the temporal bone while delivering low radiation doses and containing costs. The aim of this study was to assess, in terms of radiation dose and image quality, the possibility of using CBCT as an alternative to MSCT in patients with bionic ear implants.
Materials and methods
One hundred patients (mean age 26 years, range 7–43) with Vibrant SoundBridge implants on the round window underwent follow-up: 85 with CBCT and 15 with MSCT. We measured the average tissue-absorbed doses during both MSCT and CBCT scans. Each scan was focused on the temporal bone with the smallest field of view and a low-dose protocol. In order to estimate image quality, we obtained data about slice thickness, high- and low-contrast resolution, uniformity and noise by using an AAPM CT performance phantom.
Results
Although the CBCT images were qualitatively inferior to those of MSCT, they were sufficiently diagnostic to allow evaluation of the position of the implants. The effective dose of MSCT was almost three times higher than that of CBCT.
Conclusions
Owing to low radiation dose and sufficient image quality, CBCT could be considered an adequate technique for postoperative imaging and follow-up of patients with bionic ear implants.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The amygdala plays a central role in the fronto-limbic network involved in the processing of emotions. Structural and functional abnormalities of the amygdala have recently been found in ...schizophrenia, although there are still contradictory results about its reduced or preserved volumes.
In order to address these contradictory findings and to further elucidate the possibly underlying pathophysiological process of the amygdala, we employed structural magnetic resonance imaging (MRI) and diffusion weighted imaging (DWI), exploring amygdalar volume and microstructural changes in 69 patients with schizophrenia and 72 matched healthy subjects, relating these indices to psychopathological measures.
Measuring water diffusivity, the apparent diffusion coefficients (ADCs) for the right amygdala were found to be significantly greater in patients with schizophrenia compared with healthy controls, with a trend for abnormally reduced volumes. Also, significant correlations between mood symptoms and amygdalar volumes were found in schizophrenia.
We therefore provide evidence that schizophrenia is associated with disrupted tissue organization of the right amygdala, despite partially preserved size, which may ultimately lead to abnormal emotional processing in schizophrenia. This result confirms the major role of the amygdala in the pathophysiology of schizophrenia and is discussed with respect to amygdalar structural and functional abnormalities found in patients suffering from this illness.
Several, although not all, of the previous small diffusion-weighted imaging (DWI) studies have shown cortical white-matter disruption in schizophrenia.
To investigate cortical white-matter ...microstructure with DWI in a large community-based sample of people with schizophrenia.
Sixty-eight people with schizophrenia and 64 healthy controls underwent a session of DWI to obtain the apparent diffusion coefficient (ADC) of white-matter water molecules. Regions of interest were placed in cortical lobes.
Compared with controls, the schizophrenia group had significantly greater ADCs in frontal, temporal and occipital white matter (analysis of covariance, P < 0.05).
Our findings confirm the presence of cortical white-matter microstructure disruption in frontal and temporo-occipital lobes in the largest sample of people with schizophrenia thus for studied with this technique. Future brain imaging studies, together with genetic investigations, should further explore white-matter integrity and genes encoding myelin-related protein expression in people with first-episode schizophrenia and those at high risk of developing the disorder.
Introduction Vascular changes in the brain are relevant in schizophrenia e.g. 1 and in bipolar disorder 2. The study of first episode psychosis (FEP) allows the analysis of brain morphology and ...function without confounds due to chronicity. Objectives To characterize brain perfusion in FEP. Aims To see if FEP exhibit modified perfusion in respect to healthy controls (HC), and identify the most affected brain areas. Methods We acquired T1 and DSC images of 35 FEP patients (45 +/- 10 years old) and 35 HC (42 +/- 8), using Gadolinium (0.1 mmol/Kg). We computed cerebral blood volume (CBV), cerebral blood flow (CBF) and mean transit time (MTT) 3 in the whole brain and in left and right frontal, parietal, temporal and occipital lobes, insula, caudate and cerebellum Results Mean values of all quantities resulted lower in patients, up to 12% for CBV in right frontal lobe, 11% for CBF in left cerebellum and 16% for MTT in right frontal lobe. We used a support vector machine (SVM) to classify subjects on the basis of the histogram of perfusion values. We found that the classification reached accuracies over 80%, especially in the frontal brain areas. Conclusions FEP show altered perfusion parameters, which allow automatic classification with good accuracy, showing that brain vascular characteristics can be considered as marker of psychosis. 1 Peruzzo et al (2011). J Neural Transm, 118, 4:563-70. 2 Agarwal et al (2008). J Affect Disord, 110, 1-2:106-14. 3 Ostergaard et al (1996). Magn Reson Med, 36, 5:715-25.
Objective: The objective of the study was to compare the cerebral distribution of white matter lesions (WMLs) between migraine patients with different aura symptoms.
Methods: Migraine with aura (MA) ...patients were consecutively enrolled as part of the Shunt-Associated Migraine (SAM) study. According to clinical symptoms, aura was classified as motor, aphasic, sensory, visual or vertebrobasilar. Standard and FLAIR (fluid attenuated inversion recovery) T2-weighted MRI sequences were inspected for WMLs by three independent raters blinded to clinical data. WMLs were assessed in the periventricular areas (PV-WMLs) with the Fazekas scale and in the deep white matter (D-WMLs) with the Schelten's scale. Interobserver agreement was good to excellent (k = 0.64 to 0.96, p < .0001).
Results: One hundred and eighty-five patients (77% women) were included. Aura symptoms were classified as visual in 172 (99%) patients, sensory in 76 (42%), aphasic in 54 (30%), motor in 39 (21%) and vertebrobasilar in 17 (9%) patients. One hundred and four patients (57%) exhibited more than one type of aura. D-WMLs were mainly detected in the frontal lobes (86%). There was no association between type of aura and the presence of WMLs in any cerebral location.
Conclusion: Aura symptoms do not influence the cerebral distribution of WMLs associated with migraine disease.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
PDF
