technetium-tc-99m-exametazime and Diseases-in-Twins

To evaluate the relationship between regional cerebral blood flow (rCBF) and chronic fatigue syndrome (CFS) in monozygotic twins discordant for CFS.. The authors conducted a co-twin control study of 22 monozygotic twins in which one twin met criteria for CFS and the other was healthy. Twins underwent a structured psychiatric interview and resting technetium 99m-hexamethyl-propyleneamine oxime single photon emission computed tomography of the brain. They also rated their mental status before the procedure. Scans were interpreted independently by two physicians blinded to illness status and then at a blinded consensus reading. Imaging fusion software with automated three-dimensional matching of rCBF images was used to coregister and quantify results. Outcomes were the number and distribution of abnormalities at both reader consensus and automated quantification. Mean rCBF levels were compared by using random effects regression models to account for the effects of twin matching and potential confounding factors.. The twins with and those without CFS were similar in mean number of visually detected abnormalities and in mean differences quantified by using image registration software. These results were unaltered with adjustments for fitness level, depression, and mood before imaging.. The study results did not provide evidence of a distinctive pattern of resting rCBF abnormalities associated with CFS. The described method highlights the importance of selecting well-matched control subjects.

Topics: Adult; Brain; Case-Control Studies; Cerebrovascular Circulation; Diseases in Twins; Fatigue Syndrome, Chronic; Female; Humans; Interview, Psychological; Male; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Twins, Monozygotic

The value of functional and morphological neuroimaging in the early diagnosis of Alzheimer's disease (AD) is still debated. Described here are cerebral perfusion and linear measures of medial temporal lobe atrophy in 2 monozygotic twins discordant for AD who were investigated with technetium 99m-hexamethylpropy-leneamineoxime single-photon emission tomography (SPET) and magnetic resonance (MR) imaging. Both showed pathological cortical perfusion findings on SPET, while medical temporal lobe atrophy was present only in the affected twin. MR measures of medial temporal lobe atrophy have greater agreement with clinical data than do SPET measures of cerebral perfusion. Evaluation of atrophy may be useful in the early diagnosis of AD.

Topics: Activities of Daily Living; Alzheimer Disease; Atrophy; Cerebrovascular Circulation; Diseases in Twins; Electroencephalography; Female; Follow-Up Studies; Humans; Magnetic Resonance Imaging; Middle Aged; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Temporal Lobe; Tomography, Emission-Computed, Single-Photon; Twins, Monozygotic

Tc-99m HMPAO SPECT was used to evaluate regional blood flow in one monozygotic twin who had angiographically proven moyamoya disease. Focal and global reduced regional cerebral perfusion were observed in both patients with Tc-99m HMPAO SPECT studies. There was good correlation between the localization and degree of regional cerebral blood flow abnormalities and the severity and stage of clinical symptoms on angiography. These results suggest that Tc-99m HMPAO SPECT is a useful method in the detection of hemodynamic abnormalities in moyamoya disease.

Topics: Brain; Cerebrovascular Circulation; Child, Preschool; Diseases in Twins; Female; Humans; Moyamoya Disease; Organotechnetium Compounds; Oximes; Radiography; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Twins, Monozygotic