Jae-Wook Cho

Dopa-responsive Dystonia with a Novel Initiation Codon Mutation in the GCH1 Gene Misdiagnosed as Cerebral Palsy

Dopa-responsive dystonia (DRD) is a clinical syndrome characterized by childhood-onset dystonia and a dramatic response to relatively low doses of levodopa. However, patients with DRD can be misdiagnosed as cerebral palsy or spastic diplegia due to phenotypic variation. Here we report a young woman with DRD who were severely disabled and misdiagnosed as cerebral palsy for over 10 yr. A small dose of levodopa restored wheelchair-bound state to normality. However, thoracolumbar scoliosis has remained as a sequel due to late detection of DRD. Genetic analysis by using PCR-direct sequencing revealed a novel initiation codon mutation (c.1A>T; p.Met1Leu) in GTP cyclohydrolase 1 (GCH1) gene. Although it is known that DRD can be misdiagnosed as cerebral palsy, this case reinforces the importance of differential diagnosis of DRD from cerebral palsy.

Evaluation of brain iron content in idiopathic REM sleep behavior disorder using quantitative magnetic resonance imaging

BACKGROUND Neuroimaging studies in patients with idiopathic rapid eye movement sleep behavior disorder (iRBD) show similar structural and functional changes to alpha-synucleinopathies, including PD. Until now, there have been few attempts to characterize brain iron deposition in iRBD. The aim of this study was to investigate brain iron content in patients with iRBD using quantitative magnetic resonance imaging (MRI). METHODS 3-T MRI was performed in 15 patients with iRBD and 20 age-matched healthy control subjects. In order to evaluate the iron-related neurodegenerative changes, we assessed volume and transverse relaxation rate (R2*) simultaneously. We used both region-based and voxel-based analysis. RESULTS No significant differences in R2* values were found between iRBD groups and healthy control subjects. There were no areas of significantly reduced or increased gray matter and white matter volume in the iRBD group. Instead, lateral ventricle volumes measured automatically by FreeSurfer were significantly larger in patients with iRBD than in healthy controls (P < 0.05). CONCLUSION The present study suggests that iron-related R2* values may not be an imaging biomarker for neurodegeneration in iRBD.

Characterizing paramagnetic signal in a patient with Wilson's disease by susceptibility-weighted imaging

Department of Neurology, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, South Korea Department of Nuclear medicine, Medical Research Institute, Pusan National University Hospital, Busan, South Korea Department of Neurology and Radiology, Medical Research Institute, Pusan National University Yangsan Hospital, Yangsan, South Korea

Obstructive hydrocephalus due to CNS toxocariasis

A 46-year-old man developed intermittent headache, diplopia, and visual obscuration for two months. Funduscopic examination showed optic disk swelling in both eyes. Brain MRI exhibited hydrocephalus and leptomeningeal enhancement at the prepontine cistern, left cerebellopontine angle cistern and bilateral cerebral hemisphere, and hemosiderin deposition along the cerebellar folia. CSF analysis revealed an elevated opening pressure with xanthochromic appearance and small amount of red blood cells. Antibody titer against Toxocariasis using ELISA was elevated both in blood and CSF. Obstructive hydrocephalus and hemosiderin deposition in this case may result from the active inflammatory process due to CNS toxocariasis within the subarachnoid space.

Seizure duration determined by subdural electrode recordings in adult patients with intractable focal epilepsy.

Background and Purpose: To investigate the duration of seizures and its relationship to seizure type, epilepsy syndrome, and seizure clustering. Methods: We examined 1,251 seizures from 152 patients who underwent video-electrocorticographic monitoring with subdural electrodes. Their seizure duration, seizure types, epilepsy syndromes, and seizure clusters were analyzed. Results: The median seizure duration was 91.5s (4–1016s). There were 34 (2.7%) seizures lasting > 5 minutes in 20 (13.2%) patients. There was a significant difference in seizure duration according to seizure types (p < 0.0001), but not to epilepsy syndromes. There were 99 seizure clusters in 67 (44.1%) patients. The first seizure in a cluster of seizures tended to last longer than non-cluster seizures (median 98s versus 89s, p = 0.033). Seizure duration was significantly longer in mesial temporal lobe epilepsy than in neocortical lobe epilepsy (median 103s versus 87s, p = 0.041). Rate of seizure cluster was lower in mTLE (38.0%) than in NLE (47.1%), but this difference was not significant. Conclusions: Seizure durations were different among seizure types. Seizure clustering also differ between patients with mTLE and those with NLE, which suggests different seizure generation and propagation among different epileptogenic foci. This study has implications for the identification of abnormally prolonged seizures.

Fatigable ptosis as an initial presentation of adult-onset Leigh syndrome

A 20-year-old man presented with bilateral fatigable ptosis for 1 month. On examination, there was bilateral incomplete ptosis, which deteriorated during upward gaze and improved at rest (figure, A and B). Tests for myasthenia gravis were all negative. Brain MRI showed symmetric hyperintensities at periaqueductal gray matter on T2- and diffusion-weighted images (figure, C). CSF lactic acid was elevated. Mitochondrial genome test demonstrated a homoplasmic T9176C mutation in the MT-APT6A gene, known as pathogenic mutation of Leigh syndrome.1 In our patient, fatigable ptosis may be ascribed to the dysfunction at centrally located synapse between the nuclear complex of the third nerve and supranuclear pathways.2

Disabling Head Tremor in a Patient with DYT1 Mutation

Dystonic head tremor is known to be a feature in some patients with DYT1 mutation. However, isolated tremor of the head without relevant cervical dystonia has rarely been described. We report here a patient with the three-bp GAG deletion in the DYT1 gene (904_906delGAG) who had severe head tremor in the frame of a generalized limb dystonia.