       Document 0265
 DOCN  M9620265
 TI    Spatial data analysis in the quantitative assessment of cerebral white
       matter pathology on MRI in HIV infection.
 DT    9602
 AU    Corrigall RJ; Chong WK; Paley M; Wilkinson ID; Lantos P; Everall I;
       Maudsley Hospital, London, UK.
 SO    Neuroradiology. 1995 Aug;37(6):429-33. Unique Identifier : AIDSLINE
       MED/96038430
 AB    This study was carried out using MRI (proton density--and T2-weighted)
       on 16 HIV-negative controls, 9 symptom-free HIV-positive patients and 25
       with CDC IV HIV disease. The studies from this last group had previously
       been allocated by a radiologist to the following categories: 8 with
       focal mass lesions and normal-appearing white matter; 9 with diffuse
       encephalopathy (high signal on T2-weighted images, affecting most or all
       of the white matter) and 8 with patchy encephalopathy (high signal
       affecting only one or two areas within the white matter). Moran's I, a
       statistic of spatial autocorrelation, was calculated for the grey-scale
       values of a sampled pixel array from a central white matter region of
       each of the images. All values of Moran's I calculated in this study
       showed a large positive excess over the expected value under
       randomisation, indicating highly significant positive auto-correlation
       in the spatial arrangement of the grey-scale values. On T2-weighted
       images a statistically significant increase in the mean value of Moran's
       I, compared with controls, was found in the diffuse encephalopathy
       group, indicating that quantifiable changes in the spatial
       autocorrelation of pixel data can be related to recognised qualitative
       changes in the appearance of white matter in subjects with HIV disease.
       A lesser, but significant, rise in the mean value of Moran's I was also
       found in the focal mass lesion group, suggesting that changes in spatial
       autocorrelation may indicate pathological change in advance of
       qualitative MRI changes.
 DE    AIDS Dementia Complex/*DIAGNOSIS  Brain/*PATHOLOGY  Cerebral
       Cortex/PATHOLOGY  Cerebral Ventricles/PATHOLOGY  Demyelinating
       Diseases/DIAGNOSIS  Diagnosis, Differential  Human  *HIV-1  Magnetic
       Resonance Imaging/*METHODS  Neuropsychological Tests  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

