Effect of white matter hyperintensity on medial temporal lobe atrophy in Alzheimer's disease.

BACKGROUND: Medial temporal atrophy (MTA) is a recognized marker of Alzheimer's disease (AD), and white matter hyperintensities (WMH) are frequently observed on MRI of AD. The purpose of this study was to understand the role of WMH in MTA. METHODS: Subjects were 94 probable AD patients and 51 cognitively normal subjects. WMH was assessed based on the severity of deep WMH (DWMH) and periventricular WMH (PWMH). Each structural volume was evaluated using the Individual Brain Atlases from the Statistical Parametric Mapping Toolbox. RESULTS: There were no significant differences between subjects with and without WMH in terms of general cognitive function scales. Subjects with AD with WMH had decreased volume in the bilateral orbital frontal gyrus, frontal rectus gyrus, and olfactory gyrus, but not in the medial temporal lobes. After correcting for differences in DWMH, age and Clinical Dementia Rating Scale (CDR), AD with PWMH showed decreased volumes in the bilateral hippocampi. AD with PWMH showed worse scores on the Clinical Dementia Rating-Sum of Boxes and Barthel-ADL, and some frontal executive function tests. Those with DWMH did not show any reductions in the medial temporal lobes. CONCLUSION: WMH in AD is not associated with medial temporal lobe atrophy, but PWMH is independently correlated with hippocampal volume reduction.

[A case of mosaic ring chromosome 4 with subtelomeric 4p deletion].

Ring chromosome is a structural abnormality that is thought to be the result of fusion and breakage in the short and long arms of chromosome. Wolf-Hirschhorn syndrome (WHS) is a well-known congenital anomaly in the ring chromosome 4 with a partial deletion of the distal short arm. Here we report a 10-month-old male of mosaic ring chromosome 4 with the chief complaint of severe short stature. He showed the height of -4 standard deviation, subtle hypothyroidism and mild atrial septal defect/ventricular septal defect, and also a mild language developmental delay was suspected. Brain magnetic resonance imaging showed multifocal leukomalacia. Chromosomal analysis of the peripheral blood showed the mosaic karyotype with [46,XY,r(4)(p16q35)[84]/45,XY,-4[9]/91,XXYY, dic r(4;4)(p16q35;p16q35)[5]/46,XY,dic r(4;4)(p16q35;p16q35)[2]]. FISH study showed the deletion of the 4p subtelomeric region with the intact 4q subtelomeric and WHS region. Both paternal and maternal karyotypes were normal. We compared the phenotypic variation with the previously reported cases of ring chromosome 4. The ring chromosome 4 with the subtelomeric deletion of short arm seems to be related with the phenotype of short stature.