Jae-Young An

Poststroke Restless Legs Syndrome and Lesion location : Anatomical Considerations

Several case studies have reported on restless legs syndrome (RLS) associated with stroke. In this study, we investigated the prevalence and the lesion topography of poststroke RLS. There were 137 patients with ischemic stroke included in this study. The diagnosis of RLS was made 1 month after the index stroke using the criteria established by the International RLS Study Group. All patients enrolled underwent magnetic resonance imaging within 7 days of the onset of the stroke. The prevalence of stroke‐related RLS was calculated, and the topography of the associated ischemic lesions was analyzed. Among 137 patients, 17 patients (12.4%) were diagnosed with RLS after a stroke. Stroke‐related RLS was found in 10 out of 33 patients with a basal ganglia/corona radiata infarct (30.3%), 1 out of 8 patients with an internal capsular infarct (12.5%), and 1 out of 7 patients with a thalamic infarct (14.3%). In addition, one out of 54 with a cortical lesion with/without subcortical involvement (1.9%), and 4 out of 18 patients with a pontine lesion (22.2%) had RLS. The analysis of the lesions in the cortical and subcortical group showed only 1 patient in the cortical group had stroke‐related RLS, whereas 16 in the subcortical group had stroke‐related RLS. The results of this study suggest that lesions of the subcortical brain areas such as the pyramidal tract and the basal ganglia‐brainstem axis, which are involved in motor functions and sleep‐wake cycles, may lead to RLS symptoms in patients after an ischemic stroke.

The severity of leukoaraiosis correlates with the clinical phenotype of Parkinson’s disease

The impact of leukoaraiosis on Parkinsons disease (PD) has not been completely explained. We evaluated 141 patients with PD to assess the role of leukoaraiosis and determined its influence on the clinical phenotype of PD. Clinical assessments during off medication and leukoaraiosis grading were performed according to the atherosclerosis risk in communities (ARIC) study. Patients were grouped into two phenotypes, tremor or postural instability and gait difficulty (PIGD)-dominant groups. Associations between the age at onset, gender, disease duration, cardiovascular risk factors, leukoaraiosis grade and the disease phenotype were analyzed. In addition, the role of the leukoaraiosis grade in relationship to the parkinsonian motor handicaps was evaluated. The leukoaraiosis correlated with the severity of the clinical symptoms of PD as measured by the United Parkinsons disease rating scale (UPDRS) scores and the Hoehn and Yahr (H + Y) stage. There were significant correlations observed between the leukoaraiosis grade and specific motor handicaps especially those with axial symptoms. Multivariate logistic regression analysis showed that the leukoaraiosis grade was independently associated with the PIGD motor phenotype of PD. The leukoaraiosis grade was independently associated with the PIGD motor phenotype of PD; this might be explained by the affects on nondopaminergic subcortical pathways. These results have implications for clinical management of PD with regard to the control of vascular risk factors.

The leukoaraiosis is more prevalent in the large artery atherosclerosis stroke subtype among Korean patients with ischemic stroke

BackgroundSeveral studies have suggested that the specific stroke subtype may influence the presence of leukoaraiosis in patients with ischemic stroke. We investigated the association between stroke subtype and leukoaraiosis in Korean patients with ischemic stroke by MRI.MethodsThere were 594 patients included in this study that were classified as large artery disease, lacune and cardioembolic stroke. For large-artery disease, the analysis focused on the intracranial or extracranial location of the stenosis, and the multiplicity of the stenotic lesions. Leukoaraiosis grading was performed according to the Atherosclerosis Risk in Communities Study.ResultsThere was a significant association between leukoaraiosis and the stroke subtypes; the large-artery-disease group had a higher prevalence of leukoaraiosis than did the other groups (55.4% in the large-artery-disease group, 30.3% in the lacunar group and 14.3% in the cardioembolic group, P = 0.016 by chi-square test). On the multivariate linear regression analysis, age, the presence of hypertension, previous stroke and stroke subtype were independently associated with the presence of leukoaraiosis. In the sub analysis of the large-artery-disease group, the leukoaraiosis had a tendency to be more prevalent in the mixed and intracranial stenosis group than did the extracranial stenosis group (45.5% in the mixed group, 40.3% in the intracranial group and 26.9% in the extracranial group, P = 0.08 by chi-square test).ConclusionThe association of leukoaraiosis with large-artery disease in this study might be due to the relatively high prevalence of intracranial occlusive lesions in Korean stroke patients compared to other ethnic groups.

Effects of zonisamide on isolated head tremor

Background and purpose:  The medical treatment available for patients with essential tremor (ET) is often inadequate. Furthermore, the efficacy of the medical treatments currently available for patients with ET of cranial nerve areas is less satisfactory than that of the medical treatments available for patients with ET involving the upper extremities. This pilot study was performed to evaluate whether zonisamide (ZNS) is effective in the treatment of patients with isolated head tremor.

Novel mutation in the HSN2 gene in a Korean patient with hereditary sensory and autonomic neuropathy type 2

AbstractHereditary sensory and autonomic neuropathies (HSAN) are a group of clinically and genetically heterogeneous disorders that are associated with sensory dysfunction. Among these, HSAN type 2 (HSAN2; MIM 201300) is a rare recessive disease that is characterized by an early age of onset with distal and proximal sensory loss, dysfunction of the autonomic nervous system, loss of the tendon reflex, the presence of various mutilations, and the slow progression of the disease over time. The authors report a Korean patient with the clinical features of HSAN2, who was compound heterozygous for two loss-of-function mutations in the HSN2 gene: c.217C>T (Gln73X) and c.1134_1135insT (Asp379fsX1). The Gln73X mutation was a novel mutation while the Asp379fsX1 mutation has recently been reported in a Japanese patient with HSAN2. These results expanded the spectrum of mutations of the HSN2 gene by identifying a novel truncating mutation in a Korean patient and further support the hypothesis that HSN2 is a causative gene for HSAN2.

The relationship between low bone mineral density and Parkinson’s disease in a Korean population

There have been few studies concerning osteoporosis in patients with Parkinsons disease (PD), even though patients with PD have a high incidence of falls. Using a Korean population, we investigated the association between bone mineral density (BMD) and PD. A total of 107 patients with PD were compared with age-matched and sex-matched normal controls. Using the Hoehn & Yahr staging system, we classified the patients with PD into three subgroups. Parts II and III of the Unified Parkinsons Disease Rating Scale were administered to evaluate the relationship between the severity of PD and BMD. In conclusion, in the PD population we found that decreased BMD was related to the severity of immobility of patients, and that BMD changes were greater at the femoral neck than the spine area. Therefore, we assert that clinicians should consider administering screening tests to elderly patients with PD and provide appropriate primary or secondary prophylactic treatment for osteoporosis.

Donepezil-induced jaw tremor.

A 76-year-old woman was admitted to our hospital due to recent memory impairment. She had no history of essential tremor, parkinsonian symptoms or neuroleptic administration. The results of a neuropsychological test conducted during her first visit revealed that she had mild cognitive impairment (Table 1), and she was prescribed donepezil at a dose of 5 mg/day. However, within 2 days of donepezil treatment she began to experience jaw tremor that did not involve any other facial muscles. Her jaw tremor subsided when she closed her mouth or clenched her teeth, but recurred immediately when her mouth was held slightly open or during sustained phonation. The pattern of this tremor did not change in frequency or amplitude with distraction maneuvers, including volitional slow repetitive activation of different muscles innervated by the facial nerve. There were no limb tremors. The results of complete blood count, liver function test, electrolytes, and thyroid function test were all within the normal ranges, and the findings of magnetic resonance imaging of brain were unremarkable. Thus, we thought that the patient’s jaw tremor was due to the administration of donepezil. The jaw tremor subsided after the donepezil was terminated and had nearly completely disappeared by 7 day after the discontinuation of the donepezil.

Arterial stiffness and impaired renal function in patients with Alzheimer’s disease

Impaired renal function is regarded as a risk factor for vascular disease, and is associated with an increasing pulse wave velocity. Both renal dysfunction and arterial stiffness are associated with cognitive impairment and dementia. However, there have been few studies that have evaluated the relationship between albuminuria and arterial stiffness and Alzheimer’s disease (AD). We investigated renal dysfunction and arterial stiffness in AD, as compared to normal controls, patients with subjective memory impairment (SMI), and patients with mild cognitive impairment (MCI). Case–control comparisons were made between 29 patients with AD, 27 with MCI, 14 with SMI, and 25 healthy controls. All patients underwent clinical and neuropsychological assessments. The urine albumin/creatinine ratio and estimated glomerular filtration rate (eGFR) were determined. Pulse wave velocity and the ankle-brachial index were used to evaluate arterial stiffness. The urine albumin/creatinine ratio and eGFR were significantly different in patients with AD, compared with the results from cognitive normal controls. The pulse wave velocity was increased and the ankle-brachial index was decreased in AD. The eGFR was well correlated with other indices and decreasing eGFR was independently associated with cognitive decline. In conclusion, albuminuria, a decreased glomerular filtration rate, an increased pulse wave velocity, and a decreased ankle-brachial index were associated with AD. These finding suggests that impaired renal functions and arterial stiffness are related to AD, in which a vascular mechanism plays a prominent role in the cognitive dysfunction associated with the disease.

Pure Sensory Deficit at the T4 Sensory Level as an Isolated Manifestation of Lateral Medullary Infarction

In rare cases restricted sensory deficits along the somatotopic topography of the spinothalamic tract can develop from a lateral medullary infarction. To our knowledge, isolated dermatomal sensory deficit as a single manifestation of a lateral medullary infarction has not been reported previously. A 58-year-old man presenting with sudden left-sided paresthesia complained of sensory deficit of pain and temperature below the left T4 sensory level without other neurologic deficits. Diffuse- and T2-weighted magnetic resonance imaging (MRI) of the brain showed high signal intensities in the right lower medulla oblongata, whereas thoracic-spine MRI and somatosensory evoked potentials produced normal findings.

Co-Occurrence of Astasia and Unilateral Asterixis Caused by Acute Mesencephalic Infarction

well controlled. However, there were no histories of hepatitis, smoking and heavy alcohol consumption. He has taken aspirin 100 mg, clinidipine 10 mg, imidapril 10 mg and acarbose 50 mg daily. At the emergency room, the blood pressure was 160/90 mm Hg, the pulse rate 78/min, the respiration rate 22/min and the body temperature 36.8 ° C. On neurologic examination, he was alert and oriented with fluent but mildly slurring speech. Cranial nerve functions and muscle strength were normal with the exception of minimal drift of the right upper extremity (Medical Research Council grade IV+/V). Sensory examination revealed normal findings. The reflexes were symmetrical, and the plantar responses were flexor. When both his hands were outstretched, postural lapses with arrhythmic losses of extensor muscle tone that developed upon instruction to maintain the wrist in an extended position, so-called asterixis, or flapping tremor, was observed in the right hand. Fingerto-nose test, rapid alternation movement and heel-to-shin test were all normal. On attempt to stand, however, he showed postural instability and gait disturbance unassisted due to a tendency to tilt backward or toward right, while his ability to sit was relatively preserved. Laboratory studies, including a complete blood cell and platelet count, the erythrocyte sedimentation rate, blood electrolytes, creatinine, liver enzymes, cholesterol, triglycerides and the prothrombin and partial thromboplastin Dear Sir, Astasia designates motor incoordination with inability to stand and is occasionally observed in patients with conversion hysteria [1] . Organic causes of astasia have been rarely reported. Unilateral asterixis may be caused by a focal structural brain lesion including stroke involving the thalamus, parietal lobe, frontal lobe, midbrain, basal ganglia and internal capsule, although asterixis was classically associated with metabolic derangement, particularly hepatic encephalopathy, which occurs usually bilaterally [2–5] . In addition, concurrent unilateral manifestation of astasia and asterixis due to focal cerebral lesions is extremely rare [2, 4] . To our knowledge, sudden concurrent development of asterixis and astasia as a consequence of a rostral midbrain infarction has not yet been reported. We report a patient with concurrent unilateral astasia and asterixis developed due to acute cerebral infarctions involving the rostral level of the midbrain without significant metabolic disorder.