A new method for the relative quantification of rCBF examined by 99Tcm-HMPAO SPECT

116

Five patients with the early-onset form of Alzheimer disease (AD) received GM1 ganglioside by continuous injection into the frontal horns of the lateral ventricles for a period of 12 months. The optimal GM1 dose varied between 20 and 30 mg/24 h. The patients were trained twice a week for 4–5 h with an individually designed cognitive programme, which included the use of a word processor. Neurological, neuropsychological, psychiatric and neurochemical examinations were performed a week before surgery and on days 30, 90, 180, 270 and 365 after surgery. The cerebrospinal fluid levels of the monoamine metabolites homovanillic acid and 5-hydroxyindoleacetic acid and the neuropeptide somatostatin increased. The regional cerebral blood flow showed a tendency to increase. The progression of deterioration was stopped, and motor performance and neuropsychological assessments improved. The patients became more active and felt safer in relation to other people and performing various activities. They had improved reading comprehension and a better feeling for language. They were able to write reports and short letters on a word processor. When interviewed at the end of the study, all 5 patients stated that they felt better, and their relatives reported that they had regained integrity and their joie de vivre.

Section: Ct Mri and Single-photon Emission To Assess Rcbfmentioning

confidence: 99%

Alzheimer Disease – Effect of Continuous Intracerebroventricular Treatment with GM1 Ganglioside and a Systematic Activation Programme

Svennerholm¹,

Bråne²,

Karlsson³

et al. 2002

116

“…The average method also involves a risk of misplacement of the ROIs. Therefore, we applied the alternative min-max method [11], which uses rectangular ROIs to obtain rCBF values (minimum c/p -1 in the white matter and maximum c/p -1 in the gray matter). It is easier to apply than the average method and therefore has a higher reproducibility.…”

Section: Discussionmentioning

confidence: 99%

“…The quantification of the relative rCBF was conducted according to the min-max method [11], where minimum and maximum counts per pixel (c/p) were registered in white and gray matter regions. In gray matter, rCBF was calculated as the ratio between maximum c/p in gray matter regions of interest (ROIs) to maximum c/p in the cerebellar ROI.…”

Section: Rcbf-spet Measurementsmentioning

confidence: 99%

“…rCBF can be quantified in absolute terms by positron emission tomography and xenon CT (computerized tomography) and be semiquantitatively measured by single-photon emission tomography (SPET) using different labeled isotopes. Among the methods for semiquantification, the min-max method has been reported to involve a smaller observer error and to have bet- ter reproducibility than other more commonly used methods [11]. Investigations of rCBF in FTD, using different methods, have generally found reductions in the frontal lobes [12][13][14][15][16][17].…”

Section: Introductionmentioning

confidence: 99%

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Frontotemporal Dementia Can Be Distinguished from Alzheimer’s Disease and Subcortical White Matter Dementia by an Anterior-to-Posterior rCBF-SPET Ratio

Sjögren

Gustafson

Wikkelsø

et al. 2000

Sixteen patients with frontotemporal dementia (FTD), 27 with early-onset Alzheimer’s disease, 25 with late-onset Alzheimer’s disease, 19 with subcortical white matter dementia (SWD) and 28 normal controls underwent semiquantitative regional cerebral blood flow measurement (rCBF) using single-photon emission tomography (SPET; ^99mTc-HMPAO) and either computerized tomography (CT) or magnetic resonance imaging (MRI) of the brain. An anterior-to-posterior rCBF-SPET ratio (mesial superior frontal gyrus/medial temporal lobes) was calculated, which significantly separated the FTD group from the other dementia groups and controls with a sensitivity of 87.5% and a specificity of at least 78.6%. CT/MRI was found to be helpful in the differential diagnosis between FTD and SWD. In FTD patients, the mesial superior frontal gyrus, near the polus frontalis, was found to be the region with the most reduced rCBF values.

“…The quantification of the relative rCBF was conducted according to the min-max method [19,34] where minimum and maximum counts per pixel (c/p) were registered in white and grey matter regions. In grey matter, rCBF was calculated as the ratio between max c/p in grey matter regions of interest (ROIs) to max c/p in the cerebellar ROI.…”

Section: Rcbf-spect Measurementsmentioning

confidence: 99%

Biological Correlates of Clinical Subgroups of Alzheimer’s Disease

Sjögren¹,

Wikkelsø²,

Östling³

et al. 2002

We considered it possible that the differences in clinical symptoms between two suggested subgroups of Alzheimer’s disease (AD), AD type I and AD type II, have biological correlates, for instance different metabolic profiles. Therefore, we performed regional cerebral blood flow (rCBF) measurements and investigated the cerebrospinal fluid (CSF) levels of the monoamine metabolites homovanillic acid (HVA), 5-HIAA, and HMPG in 15 patients with AD type I, in 36 patients with AD type II, in a control group and in a contrast group consisting of 16 patients with frontotemporal dementia. The results suggest that there are underlying biological correlates of the phenomenological discrepancies between AD type I and AD type II. For instance, a decreased CSF level of HVA (p < 0.001) was specific to AD type I and decreased rCBF (p < 0.05 to <0.001) in three particular regions was specific to AD type II.