technetium-tc-99m-exametazime and Aphasia--Primary-Progressive

Primary progressive aphasia (PPA) is rare. Only limited series have been reported with SPECT or PET. Moreover, in the majority of studies, the left-to-right asymmetry ratio was used, leading to difficulties in right hemisphere analyzes.. Twenty-nine patients with clinical criteria of PPA (Mesulam and Weintraub) were included and compared with 12 control subjects. Complete language examination was performed in all patients. SPECT was performed on a double-head gamma camera after intravenous injection of hexamethylpropyleneamine oxime (22 patients and 12 control subjects) or ethylcysteinate dimer (7 patients). Nineteen regions of interest (ROIs) were drawn on each hemisphere in all patients using the Talairach atlas. The perfusion index (PI = cortex-to-cerebellum ratio) was calculated for each ROI. Atrophy was quantified on MRI by consensus of 3 observers in 16 cortical ROIs. ANOVAs were used to compare the PI between (a). patients and control subjects, (b). patients with (n = 15) or without (n = 14) lexicosemantic abnormalities (LS+ vs. LS-) and patients with (n = 19) or without (n = 10) arthric disorders (A+ vs. A-), and (c). patients with or without atrophy.. In the 29 patients, the PI was significantly lower in the left temporopolar, left lateral temporal, left Wernicke, left parietal, and right lateral temporal cortex when compared with control subjects (P < 0.001). In LS+ patients versus control subjects, the PI significantly decreased in the left temporal cortex (lateral temporal; medial temporal; temporopolar; Wernicke), left Broca, left parietal, and right lateral temporal cortex (P < 0.001). In addition, LS+ versus LS- comparison showed a significant decrease in the left lateral, left medial temporal, and left Broca cortex (P < 0.001). In comparison with control subjects, the PI was not significantly different in A+ patients, whereas in A- patients the PI was significantly decreased in the left and right lateral temporal cortex, left Wernicke, and left parietal cortex. Moreover, the PI significantly decreased in the left lateral temporal region in A+ patients compared with A- patients. Finally, in patients without atrophy, the PI significantly decreased in the right and left lateral temporal cortex and the left parietal cortex (P < 0.01).. Our study demonstrates that right-handed patients with PPA present a decreased perfusion in the bilateral temporal cortex. Moreover, in these regions, morphologic abnormalities are preceded by perfusion abnormalities. Finally, our results show that large left temporal dysfunction occurs in patients with LS disorders.

Topics: Aged; Aphasia, Primary Progressive; Brain; Cysteine; Female; Humans; Language Disorders; Magnetic Resonance Imaging; Male; Neuropsychological Tests; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Speech Disorders; Technetium Tc 99m Exametazime; Temporal Lobe; Tissue Distribution; Tomography, Emission-Computed, Single-Photon

A Japanese male developed gradual loss of spontaneous speech at age 60. Three years later meaningful speech had deteriorated to the point that it had become restricted to monotonous utterances. Neuropsychological examination at age 62 showed that he had severe non-fluent aphasia. A brain MRI demonstrated mild cortical atrophy with ischemic lesions in the cerebral white matter. He was diagnosed as having primary progressive aphasia. At age 63, he was admitted to the hospital to reevaluate the neurological condition. Neurologic examination showed severe non-fluent aphasia, hyperreflexia, snout and sucking reflexes. No alien hand was observed. He was able to walk, dress, wash himself and use chopsticks as well as name real objects. At age 65, 99Tc-hexamethylpropyleneamine oxime single photon emission computed tomography (HMPAO-SPECT) revealed diffuse cerebral hypoperfusion that was particularly prominent in the left frontal lobe. An MRI showed progressive cortical atrophy with the definite atrophy of the left paracentral gyrus. The hippocampal formation and putamen were also atrophic. He died of pneumonia at age 67. The brain weighed 810 g with atrophy of the frontal lobe, globus pallidus, enlargement of the lateral ventricles and depigmentation of the substantia nigra. Microscopic examination showed severe neuronal loss and gliosis in the cerebral cortex, globus pallidus interna and substantia nigra. Ballooned neurons were observed in the cerebral cortex. Gallyas-Braak method revealed numerous astrocytic plaques and argentophilic threads in the cerebrum. Clinical diagnosis of corticobasal degeneration sometimes is difficult in individuals with atypical clinical presentations. More exact clinical and radiological criteria may warrant a diagnosis of corticobasal degeneration.

Topics: Aphasia, Primary Progressive; Atrophy; Brain; Fatal Outcome; Frontal Lobe; Gliosis; Globus Pallidus; Hippocampus; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Putamen; Radiopharmaceuticals; Substantia Nigra; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Primary progressive aphasia (PPA) is an uncommon degenerative dementia characterized by gradual impairment of language function with initial sparing of the memory domain. Using semiquantitative 99mTc-hexamethyl propyleneamine oxime (HMPAO) brain SPECT as a measure of regional cerebral blood flow (rCBF), we investigated the relationship between reduced 99mTc-HMPAO uptake and the severity of dysnomia in PPA.. Seven right-handed patients with PPA had their dysnomia assessed by the Boston Naming Test (BNT), a subtest of the Boston Diagnostic Aphasia Examination. Neuroimaging studies, including 99mTc-HMPAO brain SPECT, CT, and MRI, were performed. Correlational analysis between reduced rCBF and BNT was performed.. Brain SPECT showed a reduction in 99mTc-HMPAO uptake involving the frontal and temporal lobes in all 7 patients. CT and MRI showed mild to moderate cerebral atrophy in 4 patients. Low scores on the BNT correlated with low frontotemporal 99mTc-HMPAO (Spearman r = 0.97, P = 0.004) in the 5 patients with left-hemisphere involvement.. Decreased rCBF to the frontotemporal region characterized the cerebral abnormalities associated with PPA. The finding of focal rCBF abnormalities in the right hemisphere of 2 right-handed women corroborates that PPA symptoms may arise from a "non-left-dominant"-hemisphere degenerative process. Our results support the usefulness of rCBF SPECT imaging as a diagnostic aid in PPA.

Topics: Aged; Anomia; Aphasia, Primary Progressive; Cerebrovascular Circulation; Female; Frontal Lobe; Humans; Male; Neuropsychological Tests; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Temporal Lobe; Tomography, Emission-Computed, Single-Photon

To provide the clinician with a guide to the clinical utility of 99mTc-HMPAO single photon emission computed tomography (SPECT) and to the interpretation of specific test results in the differential diagnosis of dementia.. Three hundred and sixty three patients with dementia were studied prospectively for a median three (range 1-6) years and classified into disease groups on the basis of established clinical criteria. The degree to which different patterns of cerebral blood flow (CBF) abnormality found on 99mTc-HMPAO SPECT imaging at the time of initial patient presentation modified clinical diagnoses was determined by calculating the likelihood ratios for pairwise disease group comparisons. The optimal clinical usage of 99mTc-HMPAO SPECT was determined by calculating the percentage of significant test results for each pairwise disease group comparison.. Bilateral posterior CBF abnormality was found to significantly increase the odds of a patient having Alzheimer's disease as opposed to vascular dementia or frontotemporal dementia. Bilateral anterior CBF abnormality significantly increased the odds of a patient having frontotemporal dementia as opposed to Alzheimer's disease, vascular dementia, or Lewy body disease. "Patchy" CBF changes significantly increased the odds of a patient having vascular dementia as opposed to Alzheimer's disease. Unilateral anterior, unilateral anterior plus unilateral posterior, and generalised CBF abnormality failed to contribute to the differentiation of any of these forms of dementia.. 99mTc-HMPAO SPECT was found to be most useful in distinguishing Alzheimer's disease from vascular dementia and fronto temporal dementia, and least useful in differentiating between Alzheimer's disease and Lewy body disease, and between vascular dementia, frontotemporal dementia, and progressive aphasia. It is suggested that CBF SPECT should be used selectively and as an adjunct to clinical evaluation and CT.

Topics: Aged; Alzheimer Disease; Aphasia, Primary Progressive; Dementia; Dementia, Vascular; Diagnosis, Differential; Female; Humans; Likelihood Functions; Male; Middle Aged; Odds Ratio; Parkinson Disease; Prospective Studies; Reproducibility of Results; Sensitivity and Specificity; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Primary progressive aphasia (PPA) presents with aphasia, with or without other minor cognitive dysfunction. We report five patients with PPA to show the correlation between their clinical signs and imaging findings. The patients can be divided into those with nonfluent (group 1) and those with fluent (group 2) aphasia. The characteristic speech impairment was bradylalia in group 1 and word amnesia in group 2. Impairment of comprehension was common but mild in both groups. On MRI, patients in group 1 showed predominantly left frontal and perisylvian atrophy with reduced uptake in the same region on single photon emission computed tomography (SPECT) using technetium-99m hexamethyl propyleneamine oxime (99mTc HMPAO). Patients in group 2 showed left temporal atrophy involving the superior, middle and inferior temporal gyri, hippocampus and parahippocampal gyrus on MRI and reduced uptake in the same region on SPECT. These findings correlated well with the functional anatomy of speech impairment.

Topics: Aged; Aphasia, Broca; Aphasia, Primary Progressive; Aphasia, Wernicke; Cerebral Cortex; Dominance, Cerebral; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Neuropsychological Tests; Organotechnetium Compounds; Oximes; Sensitivity and Specificity; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon