Relationship Between the Striatal and Cerebellar Glucose Metabolism and the Response to Levodopa Treatment in Patients With Multiple System Atrophy

Abstract

Introduction: About two thirds of the patients w ith multiple system atrophy (MSA) do not respond to levodopa treatment. Postmortem pathological studies and one retrospective [F]-deoxyglucose positron em ission tom ography (FDG PET) study attributed such poor response to the stria ta l degeneration. W e prospective ly investigated the re lationsh ip between levodopa respons iveness and the m etabo lic activ ities o f the stria tum and cerebellum in M SA patients. M ethods: In 39 patients w ith M SA, the UPDRS m otor score was assessed and two sets of tim ed m otor tests were performed before and after the levodopa treatment. After quantitative FDG PET and baseline eva luation, treatm ent was started w ith 3 tab lets o f S inem et 25/250 m g a day. C lin ica l assessm ents were perform ed m onth ly for three m onths. M etabo lic activ ities o f the caudate, anterior putam en, posterior putam en, cerebe llar cortex and cerebe llar verm is were m easured. W e com pared the m easurem ents w ith m ean percentage changes of m otor function. A lso, us ing statistica l param etric m app ing (SPM ) ana lys is, we tried to find bra in areas in wh ich m etabo lism corre lated w ith the c lin ica l changes. Resu lts: M ean percentage im provem ents of UPDRS m otor scores were corre la ted w ith g lucose m etabo lism in the posterior putam en and cerebellar verm is. The m ean percentage im provem ents of perform ance in Purdue peg board test correlated w ith the glucose metabolism in the cerebellar cortex and verm is. In SPM analysis, cerebellar glucose metabolism correlated w ith the im provem ent of UPDRS m otor score and the perform ance o f two tim ed m otor tests . Conc lus ion: The integrity o f cerebe llum , as we ll as posterior putam en, m ay be an im portant factor for show ing the response to levodopa. Journal of Movement Disorders 1(1):26-32, 2008