Cerebral Blood Flow in Corticobasal Degeneration and Progressive Supranuclear Palsy

Abstract

To compare brain perfusion between corticobasal degeneration (CBD) and progressive supranuclear palsy (PSP), we investigated regional cerebral blood flow (rCBF) semiquantitatively with single-photon emission computed tomography and [123I]iodoamphetamine in six patients with CBD and five with PSP. Compared with 12 age-matched control subjects, the average of the left and right rCBF values for the CBD patients was significantly reduced in the inferior prefrontal, anterior cingulate, medial premotor, sensorimotor, posterior parietal, and superior temporal cortices as well as in the basal ganglia and thalamus, whereas only the medial premotor cortex was significantly hypoperfused in the PSP patients. Compared with the PSP patients, the CBD patients showed significantly decreased rCBF in the inferior prefrontal, sensorimotor, and posterior parietal cortices, but not in the subcortical regions. Compared with the controls, interhemispheric differences of rCBF were significant in the inferior prefrontal, sensorimotor, and posterior parietal cortices of the CBD patients but in only the medial prefrontal cortex of the PSP patients. These results indicate that rCBF reductions are more extensive and asymmetric in CBD than in PSP, although the two diseases share medial frontal involvement.

Corticobasal degeneration and Parkinson's disease assessed by HmPaO SPECT: The utility of factorial discriminant analysis

“…This is an important point because symptom asymmetry is a typical feature of CBD, [3][4][5] and metabolic or CBF asymmetry has frequently been cited in previous SPECT studies. 19,21 Using FDA, we demonstrated that automatic classification based on a decision rule can complete the visual analysis of SPECT, the latter being subjective and de- pendant on the examiner. When the complete formula was used, 100% of our patients were classified correctly with respect to their clinical symptoms.…”

“…33 Hypometabolism or a reduction in CBF in the temporal lobe has sometimes been reported in SPECT studies. 21,22 However, the cortical atrophy mainly affects the superior frontal gyrus and the pre-and postcentral regions; involvement of the inferior parietal lobulus has also often been observed in SPECT studies. 19 Consequently, the reductions in CBF in the temporoparietal and in the temporoinsular regions are better explained by an involvement of the inferior parietal lobulus rather than the temporal lobulus.…”

“…A symmetric involvement of the thalamus is mentioned in other SPECT studies using HmPaO 19 and IMP. 21,22 An asymmetry of "deep nuclei" (with no further details provided) was reported in certain SPECT studies using perfusion tracers (such as HmPaO 20 23 ].…”

“…Another interesting approach will be to compare CBD to its other differential diagnoses (principally PSP and AD) using the same methodology. CBD has already been compared to PSP 21 and AD 22 using SPECT: these studies indicated that CBF reductions are more extensive and asymmetric in CBD than in PSP and AD. Moreover, the CBF reduction seems to occur earlier in CBD than in AD.…”

“…15 HmPaO SPECT is useful for discriminating PD from dementia with Lewy bodies and AD. 18 HmPaO and 123 I-N-isopropyl-iodoamphetamine (IMP) SPECT studies in CBD have principally underlined the asymmetry of the condition, which involves the perirolandic cortex, 19 -21 the posterior parietal cortex, [21][22][23] or the inferior prefrontal cortex 21 contralateral to the more affected side of the body. To date, only one study has compared CBD and PD using SPECT in order to specify its precise value for differential diagnosis of the two conditions.…”