White matter hyperintensities and medial temporal lobe atrophy in clinical subtypes of mild cognitive impairment: the DESCRIPA study.

BACKGROUND: Clinical subtypes of mild cognitive impairment (MCI) may represent different underlying aetiologies. METHODS: This European, multicentre, memory clinic based study (DESCRIPA) of non-demented subjects investigated whether MCI subtypes have different brain correlates on MRI and whether the relation between subtypes and brain pathology is modified by age. Using visual rating scales, medial temporal lobe atrophy (MTA) (0-4) and white matter hyperintensities (WMH) (0-30) were assessed. RESULTS: Severity of MTA differed between MCI subtypes (p<0.001), increasing from a mean of 0.8 (SD 0.7) in subjective complaints (n = 77) to 1.3 (0.8) in non-amnestic MCI (n = 93), and from 1.4 (0.9) in single domain amnestic MCI (n = 70) to 1.7 (0.9) in multiple domain amnestic MCI (n = 89). The association between MCI subtype and MTA was modified by age and mainly present in subjects >70 years of age. Severity of WMH did not differ between MCI subtypes (p = 0.21). However, the combination of MTA and WMH differed between MCI subtypes (p = 0.02) CONCLUSION: We conclude that MCI subtypes may have different brain substrates, especially in older subjects. Isolated MTA was mainly associated with amnestic MCI subtypes, suggesting AD as the underlying cause. In non-amnestic MCI, the relatively higher prevalence of MTA in combination with WMH may suggest a different pathophysiological origin.

Spinal segmental dysgenesis: presentation of a rare spinal congenital abnormality.

Segmental spinal dysgenesis is a rare spinal congenital abnormality in which a segment of the spine and spinal cord fails to develop completely. This entity is often associated with other congenital anomalies such as multiple vertebral segmentation defects, congenital vertebral displacement, tethered cord, hydromyelia and syringohydromyelia.

Is total brain volume correlated to cognitive function and education in patients with Alzheimer disease?

This study aimed to correlate whole brain volume measurements with MRI in patients with Alzheimer disease and the same Mini Mental State Examination (MMSE) but different levels of education. We describe the procedure we used to create 3D models of the brain from MRI images in patients with Alzheimer disease and then took volumetric measurements of the whole brain parenchyma. After this procedure we correlated the total brain volume measurements in patients with six or fewer years of education with those who had at least 12 years of education. Twenty patients with Alzheimer disease were examined with MRI. All of them had an MMSE score between 21 and 24 and were classified as mild Alzheimer disease. Ten of the patients had at least six years of education and the remaining ten had more than 12 years of education. The examinations were done by using a Siemens Expert Plus system of 1T and the MR images were studied using an automatic algorithm. The MRI images were segmented into grey, white matter and CSF. We then measured the volume of each component and classified those in each patient in relation to years of education. The whole procedure was completed successfully in 20 patients. After the volumetric study of the total brain volume by calculating separately grey matter, white matter and CSF, we classified the patients and made the correlation between those with six or fewer years of education and those with twelve or more years of study. Correlating the whole brain volume measurements of patients with Alzheimer disease and the same MMSE but different levels of education showed that there is no significant difference between the total brain volume of the two groups of our study.

3D MR Models and Volumetric Measurements of the Brain in Patients with Alzheimer's Disease.

This study aimed to describe the procedure we use to create 3D models of the brain parenchyma from MRI images and calculate the volume of the whole brain and different compartments of the brain in patients with Alzheimer's disease. The utility of the 3D models and volumetric measurements of the whole brain parenchyma and different brain structures is discussed. Thirty-six patients with Alzheimer's disease were examined during the last six months with MRI. Fourteen of them were men and 22 were women. The patients were between 53 and 67 years old. MR images were studied using an automatic algorithm. The images from MRI were segmented and then three-dimensional models of brain were produced to calculate the brain volume and the volume of the white matter, gray matter and CSF separately. The whole procedure was completed successfully in 34 patients. The procedure was unsuccessful in two patients due to movement artifacts in MR images. It is relatively easy to create 3D models of MR images and to obtain volumetric studies. If this procedure is adjusted in patients with Alzheimer's disease, we can provide information more clearly and accurately than single images alone. The information obtained can be used in daily clinical practice such as pharmaceutical treatment planning and results or in basic clinical research.

MRI evaluation of diastematomyelia and associated abnormalities.

Fourteen children were studied with a 1Tesla scanner to assess the role of magnetic resonance (MR) imaging in the recognition and evaluation of diastematomyelia and associated abnormalities. With MRI divided spinal cord was well imaged in its entire craniocaudal extent. Fibrous bands or bony septum when it contained a marrow cavity, were also well depicted. Direct visualization of the spinal cord itself is probably the most rewarding feature of MR imaging compared with other more conventional techniques. MR imaging demonstrated associated syringohydromyelia, segmentation anomalies, scoliosis, low position of the conus medularis and intradural lipoma that they were not detected with other radiologic studies.

Falx Cerebri Ossification: CT and MRI Evaluation.

During the last three years, CT and MRI brain scans of 40 patients revealed falx cerebri partial ossification as an incidental finding. The patients had been admitted for brain CT and MRI for several reasons. In most cases, there was no problem in the differential diagnosis of falx cerebri ossification during interpretation of the cases. In a few cases, the lesion should be distinguished from calcified meningioma, small hematoma in the interhemispheric fissure and in one case there was also meningeal infiltration of breast cancer. In these cases both CT and MRI scans of the brain were evaluated and a definite diagnosis was made.