$370 Wednesday, November 9, 2005 Poster Abstracts

Shindo, K, Kaneko, E, Watanabe, H, Sugimoto, T, Ohta, E, Ohashi, K, Nagasaka, T, Shiozawa, S. University Of Yamanashi

Heading: Sympathetic activity and MIBG scilitigraphy in PD. Background: To analyze the correlation between muscle sympathetic IIerve activity (MSNA) and cardiac 123Lmetaiodobelizylgnalfidilie (MIBG) uptake in patients with Parkinson's disease (PD). Methods: We measured both parameters in 14 PD patients whose ages were 51 to 82 years (mean, 63.1 -c 8.7) years. The duration of PD was 2 to 26 years, and the disability level (modified Hoehli-Yahr stage) raliged froli1 2.0 to 4.0 (iileali, 3.2 ± 0.5). MSNA was recorded froli1 the perolieal nerve fascicles using microlieurographic methods, and then cardiac MIBG scintigraphy was performed within 1 month. We analyzed the correlation between the standardized MSNA, expressed as a percentage of the predicted value based on control subject data, and the heart-to-mediastilium ratio (H/M) or washout ratio (WR) from early and delayed MIBG images. The relationships between disease duration or disability and MSNA, the H/M ratio, or the W R were also analyzed. Results: No significant correlations were found between MSNA and H/M ratio or WR. Although MSNA was inversely correlated with disease duration and with disability level (p < 0.01), neither the H/M ratio nor the WR showed a significant correlation with disease duration or disability level. Conclusion: Since MSNA and MIBG abnormalities were not related, functional changes in addition to organic changes in cardiac sympathetic nerve endings may result in abnormal uptake of MIBG in Parkilisoli's disease.

1065 A Rapid Low Morbidity Tedlnique tot STN DBS UKlising Novel MRI Techniques

Silburn, pL2 Cook, RJ L*, Coyne, T a, Silberstein, pLS, Wasson, D ~, Fraactfia, G 3, Mellick, G 2, Sinclair, F a, Staliwell, pt. 2St Andrews Hospital Brisbane, Australia; 2Princess Alexandra Hospital Brisbane, Australia; 3North Shore Private Hospital Sydney, Australia; 4Royal North Shore Hospital Sydney, Australia; S St. George and Sutherland Hospitals, Sydney, Australia; 6Institute of Magnetic Resonance Research, Sydney, Australia

Background: We describe a rapid low morbidity technique for bilateral STN DBS insertion employed in two Australian celitres in a series of 58 patients using CT/MRI fusion. Methods: Brain lab, Radionics and Medtronic work stations were utilized for direct targeting of the dorsolateral aspect of the subthalalific nucleus with flair sequence MRI obtained from a 1.5 T or 3T magnet allowing direct visualization of the target in at least 2 and often 3 planes. In the majority of cases only a single micro- electrode (Leadpoilit-Medtronic) pass (iileali passes 1.2 per side) was required to confirm correct targeting of the STN. Using a trajectory of 60 degrees to the AC./PC plane, we find typical STN firing over 4-7mm. DBS macroelectrodes are then inserted. Frame centered reference images obtained with ilitraoperative image intensification are used to confirm precise DBS macroelectrode positioning with reference to the mJcroelectrode tract. Results: Analysis of our results demonstrated a 36% reduction in on drug UPDRS (iJre-op ON drug vs. post op ON drug ON stim, p < 0.001) and 69% reduction in l-dopa equivalent dose (p < 0.001). There was no IIlajor IIlorbidity but all overall minor Complicatioli rate of 12"/o. Conclusion: Our technique, heavily reliant on high quality imaging using novel MRI techniques allows direct targeting of the sensorimotor area of the STN and significantly reduces the number of rnicro- electrode passes required to confirm correct targeting, resul- ting ill lOW morbidity and high efficacy. Tiffs technique allows us to comfortably perform 2 bilateral lead insertions in one 8 hour operating day.

1066 Motor fluctuations related with menstrual cycle in a woman with Parldnson Disease and benefidal etleet of Entaeapone

Suarez, GP 1, Amigo, MC 1, Rodriguez Alvarez, JR 1, Mourifio, MA 1, Cebriali, E 1, Golizalez, M e. 1Neurology Department, Complejo Hospitalario de Pontevedra, Pontevedra, Spain; 2Gynecology Department, Complejo Hospitalario de Pontevedra, Pontevedra, Spain

Introduction: Changes on the severity of symptoms in premenopausal wolileli with idiopathic PD, related with the menstrual cycle, have been described before. These fluctuations may have been related with catecholestrogen, an estrogen metabolite that interacts in an inhibitory manner with COMT and subsequently influences dopamine metabolism. Case: We have consulted a woman, who began to suffer o f right hemiparkilisonism at 26 years old. Actually, she is 38 years old, and has bilateral symptoms. She has an active labor life, but she complains of two phases at the severity of her parkinsonian symptoms: a quite benign one that does not interfere with her work activities, during the first 19 days of the cycle, and another phase from the 20th to the 1st day of the cycle, durilig which, she cOlilplailis of severe motor fluctuatiolis, dose-elid diskynesis, wearilig-off pheliolilelioli and unpredictable offperiods of several hours of duration. During months, IImltiple adjustlilelits ill treatmelit were carried out, but ililprovelilelit did not take place. Finally, Stalevo was added to treatment, without increasing the dose of L-dopa/carbidopa and the premenstrual motor fluctuations disappeared. Discussion: The effectiveness of alitiparkilisoliiali drugs call be influenced by sexual hormones. Estrogen acts by dowl~-regnlatilig the expression of the enzyme COMT, and decreasing dopalifilie metabolism. We believe that the addition of Entacapone, acted compensating the lack of COMT inhibition by catecholestrogen related to the premelistrual fall of estrogen.

It seems reasonable to think that Eiitacapolie is the drug of choice to treat the premelistrual motor fluctuations in premeliopausal wolileli.

1067 The Molecular Mechanism of Levo-Dopa Induced Dyskinesia in Parldnson's Disease

Subhani, F.

Parkilisoli's disease is one of the common and complicated movement disorders. Successful therapeutic management is available since decades in the form of Levodopa. The most complicated adverse effect of this drug is induction of dyskinesia after chronic treatment for 4-10 years. After the induction of dyskiliesias the positive effects of the drug almost disappear. In the present review mechanisms, which cause the induction of L-DOPA induced dyskiliesia (DID), are elaborated. The two most important factors, which cause L-DOPA induced dyskinesia, are increased activity of the kappa opioid receptor by dynorphin and increased GABA formation by ghitamJc acid decar- boxylase. Both these chemical chaliges are caused by upregulatioli of prodynorphJli m R N A and glutamic acid dehydrogeliase mRNA, respectively, after chronic L-DOPA therapy as a result of gene expression. The ultimate effect is to reinforce the inhibitory output from the internal segment of globus pallidus to thalamus, which results in increased excitatory output from the thalamus to the cerebral cortex causilig dyskiliesia. The ilitrastriatal ilifusioli o f fosB alitiselise and 5-amilio-7-(2-pheliylethyl)-2-(2-furyl)-pyrazolo[4,3-@ 1,2,4-triazolo[1,5- c]pyrimidilie (SCH58261) have been reported for the correction of these molecular mechanisms. Prevention of these changes is hoped to prevent L-DOPA induced dyskinesia.

1068 Visualized regional hnbalance of striatal dopanlinergic function in Parkinson's disease