Showing papers by "Franz Fazekas published in 1996"

MR of cerebral abnormalities concomitant with primary intracerebral hematomas.

Abstract: PURPOSE To determine whether arteriolar vessel wall degeneration in primary intracerebral hematomas might be associated with ischemic brain lesions and clinically silent (apparently intracerebral) previous hemorrhages. METHODS The MR images of 120 consecutive patients (mean age, 60 years; age range, 22 to 84 years) with their first stroke caused by a primary intracerebral hematoma were reviewed retrospectively for coexisting ischemic damage and previous bleeds. RESULTS Early confluent to confluent white matter hyperintensities, lacunes, or infarction were present in 83 (69%) of the patients, and 39 (33%) had had previous hemorrhages consisting of microbleeds or old hematomas. Extensive white matter hyperintensities and lacunes were most frequent in patients with thalamic primary intracerebral hematomas. There was no relationship between the frequency of old hemorrhages and the location of subsequent primary intracerebral hematomas. CONCLUSION Clinically silent ischemic lesions and previous hemorrhages are a common finding on MR images of patients with primary intracerebral hematoma. They may therefore serve as evidence of diffuse microangiopathy with a possible increased risk for cerebral hemorrhage.

Estrogen replacement therapy in older women: a neuropsychological and brain MRI study.

Abstract: OBJECTIVE: To determine if postmenopausal women receiving estrogen perform better on demanding cognitive tests than women without estrogen replacement and if this beneficial effect on cognition is caused by estrogen-related prevention of silent ischemic brain damage. DESIGN: Cross-sectional study comparing postmenopausal estrogen users and non-users. SETTING: Austrian Stroke Prevention Study PARTICIPANTS: A total of 70 women currently using estrogen and 140 women who have never used estrogen from a subset of 222 postmenopausal women without neuropsychiatric or general disease undergoing extensive diagnostic work-up in a large-scale stroke prevention study among randomly selected community members. MEASUREMENTS: Neuropsychological test scores and focal brain abnormalities as well as size of ventricles and cortical sulci as assessed by 1.5 Tesla MRI. RESULTS: Estrogen users performed better than non-users on almost all neuropsychological tests administered. When ANCOVA was used to correct for slight differences between groups in age, length of education, mean arterial blood pressure and self-reported activation, values of P < .05 were noted on tasks assessing conceptualization, attention, and visuopractical skills. After adjustment for multiple comparisons, the differences in conceptualization and visuopractical skills remained significant. MRI showed a lower rate and extent of white matter hyperintensities and a significantly smaller total white matter hyperintensity area in women treated with estrogen (P = .043). The total white matter hyperintensity area was inversely related to the duration of estrogen replacement therapy (P = .040). However, there was no difference in neuropsychological performance between estrogen users with and without white matter abnormalities, and this was also supported by the lack of an association between cognitive test results and the extent of white matter disease. CONCLUSIONS: Our study demonstrated an association between estrogen replacement therapy and better cognitive functioning and a lower rate of clinically unsuspected ischemic brain damage in postmenopausal women. J Am Geriatr Soc 44:1307–1313, 1996.

Magnetic Resonance Imaging Correlates of Transient Cerebral Ischemic Attacks

Abstract: Background and Purpose MRI of patients with a transient ischemic attack (TIA) may provide more detailed morphological insights than CT. We therefore studied the frequency and type of TIA-related infarcts shown by MRI, examined the utility of intravenous contrast material, and searched for potential predictors of infarct occurrence. Methods We performed 1.5-T MRI of the brain on 62 patients (age range, 28 to 93 years; mean, 61 years) with a hemispheric TIA. Contrast material (Gd-DTPA) was given to 45 individuals. We recorded type, number, size, and location of ischemic brain lesions and related the presence of acute infarction to features of clinical presentation and probable causes for the TIA. Results MRI showed focal ischemic lesions in 50 patients (81%), but an acute TIA-associated infarct was seen in only 19 subjects (31%). In patients with an acute lesion, the infarcts were smaller than 1.5 cm in 13 (68%), purely cortical in 11 (58%), and multiple in 7 (37%) individuals. Contrast enhancement contribu...

Magnetic Resonance Imaging White Matter Hyperintensities in Clinically Normal Elderly Individuals: Correlations With Plasma Concentrations of Naturally Occurring Antioxidants

Abstract: Background and Purpose White matter hyperintensities are a common magnetic resonance imaging (MRI) observation in the elderly. They are believed to represent a subclinical form of ischemic brain damage, but the underlying pathophysiological mechanisms are still incompletely understood. We postulated that oxidative mechanisms may favor the development of these changes and therefore correlated their presence and extent with the plasma concentrations of 10 naturally occurring antioxidants. Methods We studied 355 clinically normal volunteers 45 to 75 years of age who were randomly selected from the official community register. A 1.5-T MRI of the brain and measurements of the plasma concentrations of antioxidants including zeaxanthin, cryptoxanthin, canthaxanthin, lycopene, alpha- and beta-carotene, retinol, gamma- and alpha-tocopherol, as well as ascorbate were performed in all study participants. White matter hyperintensities were graded as punctate, beginning confluent, and confluent abnormalities. Results ...

Superficial siderosis of the central nervous system: MRI findings and clinical significance.

Abstract: We reviewed a 7-year series of brain MRI examinations to determine the frequency and clinical significance of superficial siderosis of the central nervous system (SS). SS was defined by widespread bilateral signal loss at the surfaces of the cerebral or cerebellar hemispheres, the brain stem and the spinal cord on T2-weighted images. Clinical data comprised a neurological examination of identified patients and a review of their case notes. Among 8843 consecutive studies we identified 13 (0.15 %) patients with MRI evidence of SS. Only 2 had symptoms or signs characteristic of SS, such as cerebellar ataxia, hearing loss, myelopathy and dementia. Haemosiderin deposition was most widespread in both symptomatic individuals. A definite cause for SS was detected in 9 patients (69 %). None of them had a full clinical picture of SS. These data indicate SS per se to be much more frequent than may be assumed from the literature. It appears to become symptomatic only with extensive amounts of widespread iron deposition which develop preferentially with cryptic or unidentified causes of bleeding.

Pattern of cerebral blood flow and cognition in patients undergoing chronic haemodialysis treatment.

Abstract: We studied 20 patients aged 46-69 years (mean 57 years) undergoing long-term haemodialysis (HD) and 20 age- and sex-matched controls with single photon emission tomography (SPET) and 99Tcm-hexamethyl-propyleneamine-oxime to look for regional abnormalities in cerebral blood flow (CBF) and their relation to cognitive dysfunction. Global hemispheric tracer uptake relative to the cerebellum was similar in both groups, but regional over cerebellar activity was significantly reduced in the frontal cortex (85.9 +/- 5.1 vs 90.4 +/- 5.3; P = 0.01) and thalamus (99.2 +/- 8.8 vs 104.9 +/- 8.4; P = 0.05) of the HD patients. Normalization to whole-brain activity also showed the frontal cortex to be hypoactive in the HD patients, while tracer uptake was increased occipitally. These regional differences were not explained by the presence of atrophy or cerebrovascular damage seen on brain magnetic resonance imaging. The HD patients scored significantly worse on cognitive tests such as the Mini Mental State Examination (23 +/- 4 vs 28 +/- 1; P < 0.001) and Mattis Dementia Rating Scale (114 +/- 24 vs 143 +/- 1; P < 0.001). Regional activity ratios did not correlate with cognitive test scores, however. Our results indicate a disturbed pattern of CBF in HD patients, although regional SPET abnormalities did not correspond to the severity of cognitive dysfunction.

Sociodemographic predictors and concurrent validity of the Mini Mental State Examination and the Mattis Dementia Rating Scale

Abstract: The Mini Mental State Examination (MMSE) and the Mattis Dementia Rating Scale (MDRS) are among the most commonly used screening tests for dementia. The goals of our study were, firstly, to identify sociode-mographic factors which may explain the variance of test results in a community sample and, secondly, to investigate the interrelationship of these two dementia screening tests in order to evaluate the concurrent validity. A total of 1947 subjects were investigated in the setting of the Austrian Stroke Prevention Study (ASPS). Our study confirms most previous results demonstrating a relationship of higher dementia test scores with both younger age and higher educational level. Interestingly, the results we obtained suggest only a weak relationship and poor concurrent validity of the two tests. The total scores of the two tests show poor joint variance. This could lead to the conclusion that these tests evaluate different cognitive domains.

Magnetic resonance tomography of the brain in amyotrophic lateral sclerosis

Abstract: We compared the magnetic resonance imaging results of 15 patients suffering from amyotrophic lateral sclerosis (ALS) with those of 30 age-matched controls to search for disease specific cerebral abnormalities. Symmetric hyperintensity along the corticospinal tract on the proton density spin-echo sequence was exclusively found in 4 ALS patients. It was associated with younger age, rapid disease progression and evolution of symptoms starting in the lower extremities. Signal loss of the motor cortex on T2-weighted images was frequently seen in ALS (9 patients) but was also observed in controls. As MRI is capable of providing direct evidence for ALS besides excluding other diseases it should be included in the diagnostic work-up of these patients.

Nichtinvasive MR-Perfusionsbildgebung im Hirngewebe mittels Magnetisierungspräparation

Abstract: EINLEITUNG: Die physiologische Perfusion beschreibt den Transport von Nährstoffen zu Zellen und den Abtransport von Abfallprodukten. Quantitativ wird dieser Vorgang im allgemeinen durch die Menge an Blut, mit der ein Gewebe in einer bestimmten Zeit versorgt wird, erfaßt. Daraus läßt sich klinisch wertvolle Information über vaskuläre und degenerative Erkrankungen, ebenso wie über Tumorentwicklung ableiten. In der MRBildgebung ist man daher bestrebt, neue Pulssequenzen für die Abbildung bzw. für die Quantifizierung der Perfusion zu entwickeln. Waren es bis vor kurzem Indikatorverteilungsmethoden mit paramagnetischem Kontrastmittel (1), so sind es jetzt immer mehr nichtinvasive Methoden, die an Bedeutung gewinnen (2,3). Alle nichtinvasiven Methoden haben gemein, daß sie Kernspins von arteriellen Wasserstoffprotonen (arterielle Spins) als natürliche endogene Indikatoren verwenden. Durch geeignete magnetische Präparation dieser Spins proximal zur untersuchten Schicht läßt sich die Gleichgewichtsmagnetisierung im untersuchten Gewebe modulieren. Dieser Effekt ist allerdings sehr gering, wodurch eine Strategie gefordert ist, die eine Ausnutzung mit möglichst hohem SignalRauschverhältnis und gleichzeitig kurzer Akquisitionszeit erlaubt. Ein wesentlicher Aspekt dieser Arbeit war es , in unserem Perfusionsmodell (4) die TlRelaxationszeit des Blutes zu berücksichtigen und somit eine exaktere Bestimmung der Perfusion zu ermöglichen.