Behavioural and trait changes in parkinsonian patients with impulse control disorder after switching from dopamine agonist to levodopa therapy: results of REIN-PD trial.

OBJECTIVE: In this multicentre open-label trial, we compared behavioural and neuropsychiatric symptoms in Parkinson's disease (PD) patients with impulse control disorders (ICD) treated with dopamine agonists before and 12 weeks after substituting dopamine agonists with an equivalent dose of levodopa/carbidopa slow-release formulation. METHODS: Baseline characteristics of 50 PD patients with ICD were compared with those of 60 medicated and 40 drug-naive PD control groups. Neuropsychiatric trait changes in the PD-ICD group were investigated 12 weeks after the intervention. ICD behaviours were assessed via modified Minnesota Impulsive Disorders Interview (mMIDI), whereas parkinsonian severity and neuropsychiatric characters were systematically assessed with the Unified PD Rating Scale (UPDRS) and a predefined neuropsychological assessment battery. RESULTS: At baseline, ICD patients showed higher scores in the Neuropsychiatric Inventory and anxiety, anger and obsessive-compulsive traits compared with both PD control groups. In contrast, the three PD groups showed indifference in the impulsivity scales. At 12 weeks post intervention, ICD behaviours significantly improved (p<0.001, Δ modified MIDI score=‒5.27 ± 5.75) along with the UPDRS II daily activity scores (p=0.02, Δ=‒2.07 ± 4.53). Behavioural disinhibition tended to improve (p=0.06), although no significant changes were observed in the Neuropsychiatric Inventory and personality trait scores. Dopamine agonist withdrawal syndrome developed in 5.3% of the PD-ICD group. CONCLUSIONS: This study provides class IV evidence suggesting that switching from dopamine agonists to levodopa/carbidopa slow-release formulations alleviated ICD behaviours in PD patients leading to improvement in daily activities whereas neuropsychiatric traits associated with ICD persisted after the 12-week therapy. TRIAL REGISTRATION NUMBER: NCT01683253.

Neuropsychiatric Traits Associated with Refractory Impulse Control Disorder in Parkinson's Disease.

INTRODUCTION: Impulse control disorder (ICD) in Parkinson's disease (PD) is a critical nonmotor symptom with personality or neuropsychiatric traits contributing to ICD. OBJECTIVE: This study aimed to identify predictive traits for persistent or paradoxical aggravation of ICD after dopamine agonist substitution therapy for ICD in PD. METHODS: We conducted a case-control study using a database of a multicenter intervention trial for ICD in PD. The poor-outcome group was defined by showing paradoxical increases in ICD behaviors after the substitution of dopamine agonists with levodopa. We analyzed the pre-intervention personality traits associated with the poor outcome and also evaluated the risk traits for refractory ICD using a receiver-operating characteristic (ROC) curve analysis. RESULTS: The poor-outcome group showed higher levels of anger expression (p =0.007) and obsessive-compulsive traits (p =0.009) compared with the good-outcome group at the pre-intervention state. In the ROC curve analysis, the Obsessive-Compulsive Inventory showed the highest area under the curve with 80.0% sensitivity and 74.3% specificity in discriminating against the poor-outcome group. CONCLUSIONS: Our results suggest that assessment of obsessive compulsiveness may be useful for predicting the refractoriness of ICD behaviors in planning an interventional treatment for ICD in PD.

Validation of the Korean Version of the Scales for Outcomes in Parkinson's Disease-Sleep.

BACKGROUND: Sleep problems commonly occur in patients with Parkinson's disease (PD), and are associated with a lower quality of life. The aim of the current study was to translate the English version of the Scales for Outcomes in Parkinson's Disease-Sleep (SCOPA-S) into the Korean version of SCOPA-S (K-SCOPA-S), and to evaluate its reliability and validity for use by Korean-speaking patients with PD. METHODS: In total, 136 patients with PD from 27 movement disorder centres of university-affiliated hospitals in Korea were enrolled in this study. They were assessed using SCOPA, Hoehn and Yahr Scale (HYS), Unified Parkinson's Disease Rating Scale (UPDRS), Parkinson's Disease Sleep Scale 2nd version (PDSS-2), Non-motor Symptoms Scale (NMSS), Montgomery Asberg Depression Scale (MADS), 39-item Parkinson's Disease Questionnaire (PDQ39), Neurogenic Orthostatic Hypotension Questionnaire (NOHQ), and Rapid Eye Movement Sleep Behaviour Disorder Questionnaire (RBDQ). The test-retest reliability was assessed over a time interval of 10-14 days. RESULTS: The internal consistency (Cronbach's α-coefficients) of K-SCOPA-S was 0.88 for nighttime sleep (NS) and 0.75 for daytime sleepiness (DS). Test-retest reliability was 0.88 and 0.85 for the NS and DS, respectively. There was a moderate correlation between the NS sub-score and PDSS-2 total score. The NS and DS sub-scores of K-SCOPA-S were correlated with motor scale such as HYS, and non-motor scales such as UPDRS I, UPDRS II, MADS, NMSS, PDQ39, and NOHQ while the DS sub-score was with RBDQ. CONCLUSION: The K-SCOPA-S exhibited good reliability and validity for the assessment of sleep problems in the Korean patients with PD.

Comparison of dystonia between Parkinson's disease and atypical parkinsonism: The clinical usefulness of dystonia distribution and characteristics in the differential diagnosis of parkinsonism.

OBJECTIVE: Dystonia is occasionally found in patients with Parkinson's disease (PD) and atypical parkinsonisms. However, systematic comparative analysis of the association between dystonia and parkinsonism have seldom been reported. The goals of this study are to compare the clinical characteristics and distributions of dystonia between PD, multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). METHODS: We prospectively enrolled 176 patients who presented with dystonia and parkinsonism out of 1278 patients with parkinsonism. We analyzed the clinical features of dystonia and parkinsonism. RESULTS: The frequencies of dystonia were 11.0% in PD, 20.9% in MSA, 40.7% in PSP and 66.7% in CBD. Dystonia symptoms were most frequent in CBD and relatively more frequent in PSP and MSA (p<0.001). Moreover, multiple types of dystonia occurred most frequently in MSA (p=0.034). According to the distribution of dystonia, cranio-facial dystonia (CFD) and cervical dystonia (CD) were more frequently observed in atypical parkinsonism (p=0.001). In contrast, limb dystonia (LD) was more frequently observed in both PD and CBD, and truncal dystonia (TD) was more frequently detected in PD (p<0.001). Levodopa medication related dystonia was markedly more frequent in PD than in atypical parkinsonism (p=0.030). CONCLUSIONS: In this long-term, observational, prospective study, we concluded that levodopa medication related LD and TD were more frequently observed in PD than in atypical parkinsonism. Conversely, levodopa medication non-related CFD and CD were more frequently observed in atypical parkinsonism, and coexisting of some types of multiple dystonia may be unique features of atypical parkinsonism. TD or multiple types of LD, might be representative of PD rather than atypical parkinsonism.

Posterior reversible encephalopathy syndrome as an initial neurological manifestation of primary Sjögren's syndrome.

It is well known that patients with peripheral neuropathy along with autonomic involvement can also exhibit autonomic hyperactivity. There are rare cases in which these patients developed posterior reversible encephalopathy syndrome (PRES). Patients with primary Sjögren's syndrome (pSS) may be more likely to exhibit autonomic hypofunction rather than autonomic hyperfunction, which is a rare event. In the present work, we report the first known case of PRES as an initial neurological manifestation of pSS.

Impaired cognitive flexibility and disrupted cognitive cerebellum in degenerative cerebellar ataxias.

There is a clinically unmet need for a neuropsychological tool that reflects the pathophysiology of cognitive dysfunction in cerebellar degeneration. We investigated cognitive flexibility in degenerative cerebellar ataxia patients and aim to identify the pathophysiological correlates of cognitive dysfunction in relation to cerebellar cognitive circuits. We prospectively enrolled degenerative cerebellar ataxia patients with age-matched healthy controls who underwent 3 T 3D and resting-state functional MRI. All 56 participants were evaluated with the Scale for Assessment and Rating of Ataxia and neuropsychological tests including the Wisconsin Card Sorting Test, Trail Making Test, Montreal Cognitive Assessment and Mini-Mental State Examination. From MRI scans, we analysed the correlation of whole-brain volume and cortico-cerebellar functional connectivity with the Wisconsin Card Sorting Test performances. A total of 52 participants (29 ataxia patients and 23 healthy controls) were enrolled in this study. The Wisconsin Card Sorting Test scores (total error percentage, perseverative error percentage, non-perseverative error percentage and categories completed), Trail Making Test A and Montreal Cognitive Assessment were significantly impaired in ataxia patients (P < 0.05) compared to age-matched healthy controls. The Wisconsin Card Sorting Test error scores showed a significant correlation with the ataxia score (P < 0.05) controlling for age and sex. In volumetric analysis, the cerebellar right crus I, II, VIIb and VIII atrophy correlated with non-perseverative error percentage in the ataxia group. In functional connectivity analysis, the connectivity between crus I, II and VIIb of the cerebellum and bilateral superior parietal and superior temporal gyrus was significantly altered in ataxia patients. The functional connectivity between left crus II and VIIb of the cerebellum and dorsolateral prefrontal and superior frontal/parietal cortices showed a positive correlation with perseverative error percentage. The connectivity between left crus VIIb and pontine nucleus/middle cerebellar peduncle showed a significant negative correlation with non-perseverative error percentage in the ataxia group. The impaired cognitive flexibility represented by the Wisconsin Card Sorting Test was significantly impaired in degenerative cerebellar ataxia patients and correlated with disease severity. The Wisconsin Card Sorting Test performance reflects hypoactivity of the cognitive cerebellum and disrupted cortico-cerebellar connectivity in non-demented patients with degenerative cerebellar ataxia.

Caregiver Burden of Patients With Huntington's Disease in South Korea.

OBJECTIVE: This is the first prospective cohort study of Huntington's disease (HD) in Korea. This study aimed to investigate the caregiver burden in relation to the characteristics of patients and caregivers. METHODS: From August 2020 to February 2022, we enrolled patients with HD from 13 university hospitals in Korea. We used the 12-item Zarit Burden Interview (ZBI-12) to evaluate the caregiver burden. We evaluated the clinical associations of the ZBI-12 scores by linear regression analysis and investigated the differences between the low- and high-burden groups. RESULTS: Sixty-five patients with HD and 45 caregivers were enrolled in this cohort study. The average age at onset of motor symptoms was 49.3 ± 12.3 years, with an average cytosine-adenine-guanine (CAG)n of 42.9 ± 4.0 (38-65). The median ZBI-12 score among our caregivers was 17.6 ± 14.2. A higher caregiver burden was associated with a more severe Shoulson-Fahn stage (p = 0.038) of the patients. A higher ZBI-12 score was also associated with lower independence scale (B = -0.154, p = 0.006) and functional capacity (B = -1.082, p = 0.002) scores of patients. The caregiving duration was longer in the high- than in the low-burden group. Caregivers' demographics, blood relation, and marital and social status did not affect the burden significantly. CONCLUSION: HD patients' neurological status exerts an enormous impact on the caregiver burden regardless of the demographic or social status of the caregiver. This study emphasizes the need to establish an optimal support system for families dealing with HD in Korea. A future longitudinal analysis could help us understand how disease progression aggravates the caregiver burden throughout the entire disease course.

Evaluating the validity and reliability of the Korean version of Scales for Outcomes in Parkinson's Disease-Cognition.

Objective: The Scales for Outcomes in Parkinson's Disease-Cognition (SCOPA-Cog) was developed to screen for cognition in PD. In this study, we aimed to evaluate the validity and reliability of the Korean version of the SCOPA-cog. Methods: We recruited 129 PD patients from 31 clinics with movement disorders in South Korea. The original version of the SCOPA-cognition was translated into Korean using the translation-retranslation method. The test-rest method with an intraclass correlation coefficient (ICC) and Cronbach's alpha coefficient were used to assess reliability. The Spearman's Rank correlation analysis with Montreal Cognitive Assessment-Korean version (MOCA-K) and Korean Mini-Mental State Examination (K-MMSE) were used to assess concurrent validity. Results: The Cronbach's alpha coefficient was 0.797, and the ICC was 0.887. Spearman's rank correlation analysis showed a significant correlation with the K-MMSE and MOCA-K scores (r = 0.546 and r = 0.683, respectively). Conclusions: Our results demonstrate that K-SCOPA-Cog exhibits good reliability and validity.

Small deep infarction in patients with atrial fibrillation: evidence of lacunar pathogenesis.

BACKGROUND: It is difficult to clarify whether small deep infarction is caused by cardioembolism or intrinsic small vessel disease in patients with atrial fibrillation (AF). The purpose of this study was to determine whether preexisting small vessel disease would differ according to the presenting infarct pattern and to determine the factors associated with acute single small deep infarction in stroke patients with AF. METHODS: Between January 2008 and August 2012, 1,592 consecutive patients with acute ischemic stroke presenting within 7 days of symptom onset were entered in a prospectively maintained stroke registry. For the present study, 231 stroke patients with AF were enrolled irrespective of the stroke subtype. We divided these patients into 2 groups (lacunar infarct pattern, n = 20, vs. nonlacunar infarct pattern, n = 211) according to the acute infarct pattern on diffusion-weighted imaging. Patients with acute single small deep infarction on diffusion-weighted imaging were assigned to the lacunar infarct pattern group. We assessed the severity of preexisting small vessel disease by grading white matter lesions (WMLs) according to the Fazekas scale (periventricular WML score ranging from 0 to 3 and deep WML score ranging from 0 to 3 were added to give a total WML score ranging from 0 to 6), multilacunar state (number of chronic lacunes ≥2) and the presence of microbleeds. Demographic characteristics, vascular risk factors and neuroimaging data were compared between the two groups. RESULTS: Patients with a lacunar infarct pattern showed more severe WMLs than those with a nonlacunar pattern [median total WML score 2.5 (range 2-4) vs. 1.0 (0-2); p < 0.001]. A multilacunar state was more prevalent in the lacunar infarct pattern group compared with the nonlacunar pattern group (65 vs. 28.9%; p = 0.001). However, the presence of microbleeds did not differ between the groups. Multiple logistic regression analyses revealed periventricular WMLs [odds ratio (OR) 4.12, 95% confidence interval (CI) 2.14-7.92], deep WMLs (OR 3.42, 95% CI 1.75-6.66) and multilacunar state (OR 7.85, 95% CI 2.45-25.6) as the predictors of a lacunar infarct pattern. CONCLUSIONS: The severity of WMLs and chronic lacunes were independent predictors of the incident infarct pattern, which suggested that acute single small deep infarction might be caused by intrinsic small vessel disease despite the presence of concomitant AF.

Increased pulsatility index is associated with intracranial arterial calcification.

BACKGROUND/AIMS: An increase in the pulsatility index (PI) has been suggested to reflect distal vascular resistance. The purpose of the present study was to investigate the association between intracranial arterial calcification and intracranial PIs. METHODS: Consecutive patients with acute ischemic stroke or transient ischemic attack were included. The PIs of both middle cerebral arteries (MCAs) were measured by transcranial Doppler ultrasonography. Intracranial carotid artery calcification (ICAC) was assessed on computed tomography angiography, and then compared with the mean PI of both MCAs. Patients with internal carotid artery steno-occlusion were excluded from this study. RESULTS: A total of 156 patients were finally enrolled. The prevalence of diabetes increased as the PI value increased (p for trends; p = 0.025). PI was correlated with ICAC score (r = 0.413, p < 0.001) and age (r = 0.507, p < 0.001). Multiple linear regression analysis indicated that aging and ICAC were independent determinants of the PI of MCA after adjusting for sex, systolic blood pressure, smoking, and the presence of diabetes. CONCLUSIONS: This study shows that an increase in PI was correlated with the severity of ICAC, which suggests calcification-related vascular resistance might have a role in the elevation of PI.

Neurologic Dysfunction Assessment in Parkinson Disease Based on Fundus Photographs Using Deep Learning.

Importance: Until now, other than complex neurologic tests, there have been no readily accessible and reliable indicators of neurologic dysfunction among patients with Parkinson disease (PD). This study was conducted to determine the role of fundus photography as a noninvasive and readily available tool for assessing neurologic dysfunction among patients with PD using deep learning methods. Objective: To develop an algorithm that can predict Hoehn and Yahr (H-Y) scale and Unified Parkinson's Disease Rating Scale part III (UPDRS-III) score using fundus photography among patients with PD. Design, Settings, and Participants: This was a prospective decision analytical model conducted at a single tertiary-care hospital. The fundus photographs of participants with PD and participants with non-PD atypical motor abnormalities who visited the neurology department of Kangbuk Samsung Hospital from October 7, 2020, to April 30, 2021, were analyzed in this study. A convolutional neural network was developed to predict both the H-Y scale and UPDRS-III score based on fundus photography findings and participants' demographic characteristics. Main Outcomes and Measures: The area under the receiver operating characteristic curve (AUROC) was calculated for sensitivity and specificity analyses for both the internal and external validation data sets. Results: A total of 615 participants were included in the study: 266 had PD (43.3%; mean [SD] age, 70.8 [8.3] years; 134 male individuals [50.4%]), and 349 had non-PD atypical motor abnormalities (56.7%; mean [SD] age, 70.7 [7.9] years; 236 female individuals [67.6%]). For the internal validation data set, the sensitivity was 83.23% (95% CI, 82.07%-84.38%) and 82.61% (95% CI, 81.38%-83.83%) for the H-Y scale and UPDRS-III score, respectively. The specificity was 66.81% (95% CI, 64.97%-68.65%) and 65.75% (95% CI, 62.56%-68.94%) for the H-Y scale and UPDRS-III score, respectively. For the external validation data set, the sensitivity and specificity were 70.73% (95% CI, 66.30%-75.16%) and 66.66% (95% CI, 50.76%-82.25%), respectively. Lastly, the calculated AUROC and accuracy were 0.67 (95% CI, 0.55-0.79) and 70.45% (95% CI, 66.85%-74.04%), respectively. Conclusions and Relevance: This decision analytical model reveals amalgamative insights into the neurologic dysfunction among PD patients by providing information on how to apply a deep learning method to evaluate the association between the retina and brain. Study data may help clarify recent research findings regarding dopamine pathologic cascades between the retina and brain among patients with PD; however, further research is needed to expand the clinical implication of this algorithm.

Prediction of anti-vascular endothelial growth factor agent-specific treatment outcomes in neovascular age-related macular degeneration using a generative adversarial network.

To develop an artificial intelligence (AI) model that predicts anti-vascular endothelial growth factor (VEGF) agent-specific anatomical treatment outcomes in neovascular age-related macular degeneration (AMD), thereby assisting clinicians in selecting the most suitable anti-VEGF agent for each patient. This retrospective study included patients diagnosed with neovascular AMD who received three loading injections of either ranibizumab or aflibercept. Training was performed using optical coherence tomography (OCT) images with an attention generative adversarial network (GAN) model. To test the performance of the AI model, the sensitivity and specificity to predict the presence of retinal fluid after treatment were calculated for the AI model, an experienced (Examiner 1), and a less experienced (Examiner 2) human examiners. A total of 1684 OCT images from 842 patients (419 treated with ranibizumab and 423 treated with aflibercept) were used as the training set. Testing was performed using images from 98 patients. In patients treated with ranibizumab, the sensitivity and specificity, respectively, were 0.615 and 0.667 for the AI model, 0.385 and 0.861 for Examiner 1, and 0.231 and 0.806 for Examiner 2. In patients treated with aflibercept, the sensitivity and specificity, respectively, were 0.857 and 0.881 for the AI model, 0.429 and 0.976 for Examiner 1, and 0.429 and 0.857 for Examiner 2. In 18.5% of cases, the fluid status of synthetic posttreatment images differed between ranibizumab and aflibercept. The AI model using GAN might predict anti-VEGF agent-specific short-term treatment outcomes with relatively higher sensitivity than human examiners. Additionally, there was a difference in the efficacy in fluid resolution between the anti-VEGF agents. These results suggest the potential of AI in personalized medicine for patients with neovascular AMD.

Plasma neurofilament light-chain and phosphorylated tau as biomarkers of disease severity in Huntington's disease: Korean cohort data.

OBJECTIVE: To investigate neurofilament light chain (NfL), phosphorylated tau (p-Tau) and total tau (t-Tau) as plasma markers for clinical severity in Korean Huntington's disease (HD) cohort. METHODS: Genetically-confirmed 67 HD patients participated from 13 referral hospitals in South Korea. The subjects were evaluated with the Unified Huntington's Disease Rating Scale (UHDRS), total motor score (TMS) and total functional capacity (TFC), Mini-Mental Status Examination (K-MMSE), Montreal Cognitive Assessment (MoCA-K), and Beck's depression inventory (K-BDI). We measured plasma NfL, p-Tau and t-Tau concentrations using single-molecule array (SIMOA) assays. Stages of HD were classified based on UHDRS-TFC score and plasma markers were analyzed for correlation with clinical severity scales. RESULTS: Plasma NfL was elevated in both 6 premanifest and 61 full manifest HD patients compared to the reference value, which increased further from premanifest to manifest HD groups. The NfL level was not significantly correlated with UHDRS TMS or TFC scores in manifest HD patients. Plasma p-Tau was also elevated in HD patients (p = 0.038). The level was the highest in stage III-V HD (n = 30) group (post-hoc p < 0.05). The p-Tau was correlated with UHDRS TFC scores (adjusted p = 0.002). Plasma t-Tau neither differed among the groups nor associated with any clinical variables. CONCLUSIONS: This study supports plasma NfL being a biomarker for initial HD manifestation in Korean cohort, and a novel suggestion of plasma p-Tau as a potential biomarker reflecting the clinical severity in full-manifest HD.

IL-1ß induction and IL-6 suppression are associated with aggravated neuronal damage in a lipopolysaccharide-pretreated kainic acid-induced rat pup seizure model.

OBJECTIVES: Reportedly, hippocampal neuronal degeneration by kainic acid (KA)-induced seizures in rats <14 days old was enhanced by lipopolysaccharide (LPS). This study was to test the hypothesis that cytokines such as interleukin (IL)-1ß, IL-6 and tumor necrosis factor-α are associated with aggravated neuronal damage. MATERIALS AND METHODS: Sixty male Sprague-Dawley, 14-day-old rats were used. Experiments were conducted in saline, LPS + saline, saline + KA and LPS + KA groups. Intraperitoneal LPS injections (0.04 mg/kg) were administered 3 h prior to KA injection (3 mg/kg). RESULTS: The LPS + KA group showed a tendency toward shorter latency to seizure onset (p = 0.086) and significantly longer seizure duration (p < 0.05) compared with the KA group. Induction of the proconvulsant cytokine IL-1ß in rat pup brains was significantly greater in the LPS + KA group compared to the KA group (38.8 ± 5.5 vs. 9.2 ± 1.0 pg/µg; p < 0.05); however, IL-6 levels were higher in the KA group than in the LPS + KA group (108.7 ± 6.8 vs. 60.9 ± 4.7 pg/µg; p < 0.05). The difference in tumor necrosis factor-α between the LPS + KA group and the KA group was insignificant (12.1 ± 0.6 vs. 10.9 ± 2.3 pg/µg; p = 0.64). CONCLUSIONS: Our results showed an increase in the proconvulsant cytokine IL-1ß and a decrease in a potentially neuroprotective cytokine, IL-6, in rat pups treated with LPS + KA. These results warrant further investigation into the possible role of IL-1ß induction and IL-6 suppression in LPS-promoted neuronal damage.

Post-interventional microembolism: cortical border zone is a preferential site for ischemia.

BACKGROUND: Previous diffusion-weighted MRI (DWI) studies have indicated that 10-40% of patients have silent embolism during neurointerventional procedures. However, lesion patterns of the embolisms have not been adequately investigated. METHODS: DWI was taken within 7 days before and 48 h after cerebral angioplasty and stent procedures. New lesions on the follow-up DWI were analyzed in the non-treated arterial territories. Based on the arterial territories, supratentorial lesions were classified into cortical lesions and subcortical lesions. Cortical lesions were subdivided into cortical border zone and cortical proper lesions. Subcortical lesions were divided into deep perforator and internal border zone lesions. Infratentorial lesions were divided into brainstem and cerebellar lesions. RESULTS: 72 patients were included in this study. There were 223 new DWI lesions (1-23 lesions) in the non-treated arterial territories of 37 patients. There were 154 cortical lesions, 45 cerebellar lesions, 21 subcortical lesions and 3 brainstem lesions. Analysis of the distribution pattern of cortical lesions showed that 88 of 154 lesions were located at the cortical border zone. Of the subcortical lesions, 13 of 21 lesions were located at the internal border zone area, within the corona radiata and centrum ovale. Only 4 lesions were located at the deep perforator territory. Infratentorial lesions were mostly located at the cerebellar hemisphere (45/48). Most lesions were tiny infarcts (<5 mm diameter); 7 of 223 lesions were >10 mm in diameter. CONCLUSIONS: Interventional-angiography-related microembolisms mostly lodge in the cerebral cortical border zone area and cerebellar hemisphere. Microembolisms to the deep perforating artery territory are distinctly rare.

Association between pulse wave velocity and nerve conduction study in diabetic patients.

BACKGROUND/AIMS: Brachial-ankle pulse wave velocity (baPWV) is a marker of vascular stiffness and is reported to be associated with diabetic neuropathy; however, the relationship between baPWV and nerve conduction study (NCS) has yet to be examined. METHODS: Between January 2006 and December 2008, we investigated this relationship in diabetic patients. To this end, we reviewed the medical records of 100 diabetic patients for whom both baPWV and NCS had been examined. RESULTS: The mean age of patients was 55.4 ± 10.6 years, and the mean duration of diabetes mellitus was 6.3 ± 7.3 years. A statistically significant inverse correlation between baPWV and NCS was observed, especially in the lower extremity sensory NCS [superficial peroneal sensory nerve action potential (SNAP), r = -0.466, p <0.05; sural SNAP, r = -0.384, p <0.01]. A multiple linear regression analysis also demonstrated a significant association between baPWV and some parameters of NCS (SNAP of sural nerve, and nerve conduction velocity of peroneal and sural nerves). CONCLUSION: These results indicate that the degree of systemic arterial stiffness is associated with peripheral nerve status in diabetic patients, but it is unclear what this signifies and further study is needed.

Validation of the Korean Version of the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease Rating Scale.

BACKGROUND AND PURPOSE: Impulse-control disorder is an important nonmotor symptom of Parkinson's disease (PD) that can lead to financial and social problems, and be related to a poor quality of life. A nationwide multicenter prospective study was performed with the aim of validating the Korean Version of the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease Rating Scale (K-QUIP-RS). METHODS: The K-QUIP-RS was constructed using forward and backward translation, and pretesting of the prefinal version. PD patients on stable medical condition were recruited from 27 movement-disorder clinics. Participants were assessed using the K-QUIP-RS and evaluated for parkinsonian motor and nonmotor statuses and for PD-related quality of life using a predefined evaluation battery. The test-retest reliability of the K-QUIP-RS was assessed over an interval of 10-14 days, and correlations between the KQUIP-RS and other clinical scales were analyzed. RESULTS: This study enrolled 136 patients. The internal consistency of the K-QUIP-RS was indicated by a Cronbach's α coefficient of 0.846, as was the test-retest reliability by a Guttman split-half coefficient of 0.808. The total K-QUIP-RS score was positively correlated with the scores for depression and motivation items on the Unified PD Rating Scale (UPDRS), Montgomery-Asberg Depression Scale, and Rapid-Eye-Movement Sleep-Behavior-Disorders Questionnaire. The total K-QUIP-RS score was also correlated with the scores on part II of the UPDRS and the PD Quality of Life-39 questionnaire, and the dopaminergic medication dose. CONCLUSIONS: The K-QUIP-RS appears to be a reliable assessment tool for impulse-control and related behavioral disturbances in the Korean PD population.

Subtypes of Sleep Disturbance in Parkinson's Disease Based on the Cross-Culturally Validated Korean Version of Parkinson's Disease Sleep Scale-2.

BACKGROUND AND PURPOSE: This study aimed to determine the clinimetric properties of the Korean version of Parkinson's Disease Sleep Scale-2 (K-PDSS-2) and whether distinct subtypes of sleep disturbance can be empirically identified in patients with Parkinson's disease (PD) using the cross-culturally validated K-PDSS-2. METHODS: The internal consistency, test-retest reliability, scale precision, and convergent validity of K-PDSS-2 were assessed in a nationwide, multicenter study of 122 patients with PD. Latent class analysis (LCA) was used to derive subgroups of patients who experienced similar patterns of sleep-related problems and nocturnal disabilities. RESULTS: The total K-PDSS-2 score was 11.67±9.87 (mean±standard deviation) at baseline and 12.61±11.17 at the retest. Cronbach's α coefficients of the total K-PDSS-2 scores at baseline and follow-up were 0.851 and 0.880, respectively. The intraclass correlation coefficients over the 2-week study period ranged from 0.672 to 0.848. The total K-PDSS-2 score was strongly correlated with health-related quality of life measures and other corresponding nonmotor scales. LCA revealed three distinct subtypes of sleep disturbance in the study patients: "less-troubled sleepers," "PD-related nocturnal difficulties," and "disturbed sleepers." CONCLUSIONS: K-PDSS-2 showed good clinimetric attributes in accordance with previous studies that employed the original version of the PDSS-2, therefore confirming the cross-cultural usefulness of the scale. This study has further documented the first application of an LCA approach for identifying subtypes of sleep disturbance in patients with PD.

MIBG scintigraphy for differentiating Parkinson's disease with autonomic dysfunction from Parkinsonism-predominant multiple system atrophy.

Parkinson's disease (PD) with autonomic dysfunction is difficult to differentiate from Parkinsonism-predominant multiple system atrophy (MSA-p). This study aimed to analyze the validity of MIBG scintigraphy for PD with autonomic dysfunction and MSA-p. Thirty-nine patients (PD: 27 patients, MSA-p type: 12) and 12 age-matched controls were prospectively enrolled and underwent MIBG scintigraphy and autonomic function test (AFT). We separately calculated early and delayed heart-to-mediastinal (H/M) ratio and washout rates (WRs). AFT was composed of sympathetic skin reflex and parasympathetic tests based on heart rate variability. Abnormal AFT was observed in 17 (63%) of PD and 10 (83%) of MSA-p. On comparing PD with abnormal AFT with MSA-p, either the early or delayed H/M ratio in PD was not different from that in MSA-p (P > 0.05). Only the WR could differentiate PD with abnormal AFT from MSA-p (47.07 +/- 57.48 vs. 31.39 +/- 31.52, respectively) (P = 0.026). According to the results, WR may be more useful than the early and delayed H/M ratio to distinguish MSA-p from PD with abnormal AFT. Furthermore, the MIBG uptake did not reflect the disease duration or severity.

Author Correction: Multimodal imaging analyses in patients with genetic and sporadic forms of small vessel disease.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.