Incidental subcortical lesions identified on magnetic resonance imaging in the elderly. II. Postmortem pathological correlations.

Abstract

SUMMARY The pathological correlates of subcortical lesions noted on magnetic resonance imaging (MRI) in the elderly are not known. Postmortem in vitro proton MRI was performed on the brains of seven consecutive elderly patients dying of nonneurologic causes. Scans were done in the fresh and fixed states with the specimen immersed in saline and formaldehyde respectively. A 1.5 Tesla superconductive system was used with a multiple spin-echo protocol generating T 2 weighted images. Subcortical MRI lesions were localized in three dimensions and identified at brain cutting. In addition, pathological correlations were obtained from an eighth patient who underwent MRI eleven days before death. Histological examinations were performed in a blinded fashion, including control areas from the same brains. Subcortical MRI lesions were found to be associated with arteriosclerosis, dilated perivascular spaces, and vascular ectasia (p < 0.05). These histological changes were characteristic of "e~tat crible"" which, like subcortical MRI lesions, is associated with age and hypertension. Shrinkage (or atrophy) of the brain parenchyma around ectatic blood vessels would result in an extensive network of tunnels filled with extracellular water. The proton MRI signal from such areas of the brain would be increased. Gliosis and small areas of infarction occasionally coexisted with "£tat crible'," but these were not present in all areas with MRI lesions and could not be distinguished by MRI signal alone. While these appear as foci of increased signal intensity on MRI, 1 -13 it is unlikely that extensive subcortical white and gray matter infarction can occur without severe symptomatology. A chronic alteration in brain parenchyma, other than frank infarction, is therefore most likely to be responsible for the multiple, patchy, and sometimes confluent incidental lesions noted on MRI. The literature is limited regarding the pathological correlates of these lesions.Pathological correlations of incidental premortem radiological findings are difficult to perform. The pathological process often progresses to more advanced and symptomatic stages before death. Furthermore, it may be complicated by terminal events prior to postmortem examination. To circumvent these difficulties, postmortem MRI was performed in vitro on the brains of seven consecutive elderly patients dying of nonneurologic causes and autopsied at this institution. An additional elderly patient had an MRI study eleven days before dying of acute renal failure. Incidental MRI lesions were identified in these eight cases and were localized precisely at brain cutting. Gross and histologic correlations were performed, including a blinded analysis of control areas from the same brains (areas not harboring MRI lesions). Patients and MethodsThe patients represented consecutive cases over 60 years of age, who died of nonneurologic causes, and who underwent postmortem examination at the Barrow Neurological Institute. Cases with known demyelinating disease, known structural brain pathology, ...

Computed Tomography, Magnetic Resonance Imaging and Pathological Correlations in a Case of Binswanger's Disease

“…12 indeed uncommon when compared to the MR picture of white matter damage often encountered in hypertensive elderly subjects suffering from cerebrovascular symptoms but without a clinical picture of vascular dementia. 25 The latter is characterized by patchy or punctate areas of altered MR signal which correspond to pathological changes of arteriosclerosis, dilated perivascular spaces and vascular ectasia, referred to as etat crible\ 23 -26 a picture quite dissimilar to that observed in our case, or to small cystic or non-cystic infarcts. 24 CT and MR are capable of demonstrating in vivo the diffuse white matter damage of BD and should now probably be considered mandatory for differentiation of BD from other vascular dementias.…”

Association between Carotid Hemodynamics and Asymptomatic White and Gray Matter Lesions in Patients with Essential Hypertension

“…It has been reported that état criblé increases with the age and is associated with hypertension. Progressive arteriolosclerosis of the perforating arteries is assumed with a histopathology of état criblé, which renders cerebral tissue compressed and atrophied (8).…”

“…Numerous studies have demonstrated that age and hypertension are highly and independently correlated with white matter lesions, periventricular hyperintensity (PVH) and subcortical white matter hyperintensity (DSWMH) ( 4 − 7 ). The incidence of a type of ganglial gray matter lesion, état criblé, has also been reported to be increased with aging and has been associated with hypertension ( 8 ).…”

Magnetic resonance imaging abnormalities in the resection region correlate with histopathological type, gliosis extent, and postoperative outcome in pediatric cortical dysplasia

“…In a recently published neuropathological study by Miles et al, 23 analyzing much of the same cohort as the present imaging-focused study, cortical gliosis was found to be more extensive in cases of Type II CD than in those of Type I CD, potentially as a consequence of long-term brain injury. Given the correlation between increased T2 signal on MRI and gliosis, 1,18,27 we hypothesized that more pronounced gliosis (involving the full thickness of the cortex) would correlate with MRI visibility, particularly those features that relate to increased T2 or FLAIR signal intensity in either the cortex or white matter. In our analysis, all MRI features, with the exception of volume loss, were significantly more prevalent in those resection regions with diffuse gliosis.…”