Sang Ahm Lee

Regional grey matter abnormalities in juvenile myoclonic epilepsy: a voxel-based morphometry study.

Visual assessment of structural MRI is, by definition, normal in patients with juvenile myoclonic epilepsy (JME), a major subsyndrome of idiopathic generalized epilepsy (IGE). However, recent quantitative MRI studies have shown structural abnormalities in cortical and thalamic grey matter (GM) in JME. Voxel-based morphometry (VBM) is a fully automated, unbiased, operator-independent MRI analysis technique that detects regionally specific differences in brain tissue composition on a voxel-wise comparison between groups of subjects. Using VBM, we examined structural differences in cortical and subcortical GM volume (GMV) between 25 JME patients (15 women, mean age=22.7+/-5.1 years) and age- and sex-matched 44 control subjects (27 women, mean age=23.1+/-4.3 years). We also performed a correlation analysis to delineate a possible relationship between the GMV increases or reductions and the increasing duration of epilepsy. Group comparison showed GMV increases in the superior mesiofrontal region bilaterally and GMV reductions in the thalamus bilaterally in JME patients (P<0.05, corrected for multiple comparisons using false discovery rate). Correlation analysis revealed that bilateral thalamic GMV had negative correlations with the duration of epilepsy (P<0.05, corrected for multiple comparisons after small volume corrections; P<0.05, Pearson correlation test). Our findings of GMV increases in the superior mesiofrontal regions and progressive thalamic atrophy could further support the pathophysiological concept of the functional abnormalities in thalamocortical circuit in JME.

The effect of topiramate monotherapy on bone mineral density and markers of bone and mineral metabolism in premenopausal women with epilepsy.

Purpose:  To investigate the effect of topiramate on bone mass and metabolism in premenopausal women with epilepsy.

Ictal Hyperperfusion Patterns in Relation to Ictal Scalp EEG Patterns in Patients with Unilateral Hippocampal Sclerosis: A SPECT Study

Summary:  Purpose: The aims of the present study were to explore the relation between ictal scalp EEG patterns and ictal hyperperfusion patterns in patients with unilateral hippocampal sclerosis–associated mesial temporal lobe epilepsy (HS‐MTLE) by using semiquantitative single‐photon emission computed tomography (SPECT) analysis and to assess clinical significance of ictal hyperperfusion patterns.

New-onset seizures after liver transplantation: Clinical implications and prognosis in survivors

Purpose: To identify the probable etiologies and characteristics of new-onset seizures after orthotopic liver transplantation (OLT) and to assess their clinical implications and prognosis. Methods: We retrospectively analyzed the clinical, electrophysiologic and laboratory data of 17 patients with new-onset seizures after OLT among 367 adult and pediatric patients who underwent OLT between 1999 and 2001. Results: A suspected etiology of seizures was identified in most patients, including 6 (35.2%) with neurotoxicity due to immunosuppressive therapy, 4 (23.5%) with cerebrovascular disease, 3 (17.6%) with severe metabolic derangement by sepsis or rejection, and 1 each (5.8%) with hyperglycemia and brain edema due to fulminant hepatic failure. Causative factors could not be identified in 2 patients (11.8%). Seizures recurred in 15 patients (88.2%), with 9 occurring on the same day as the original seizure. Attacks caused by neurotoxicity tended to have an earlier onset, within 1 week in 4 of 6 patients, than those caused by cerebrovascular disease and sepsis/rejection, but this was not statistically significant. A total of 21 EEGs were performed in 13 patients. Eleven patients had abnormal EEG findings, of whom 4 (30.7%) showed epileptiform discharges, but the outcome of patients with epileptiform activity did not differ statistically from that of patients without such discharges (p > 0.6). The incidence of poor outcome (death or persistent vegetative state) in the group with seizures was almost 10 times higher than in the group without seizures (52.9 vs. 5.7%, p < 0.001). The prognosis of patients with seizures due to cerebrovascular disease and severe metabolic derangement by sepsis/rejection was poorer than that of patients with seizures caused by the neurotoxicity of immunosuppressive drugs (p < 0.02), suggesting that the underlying cause of seizures is important in determining prognosis. Of 8 patients who survived, 1 was lost to follow-up. The long-term outcome of seizures in surviving patients was excellent, with all survivors available for follow-up being seizure-free for a mean follow-up of 42.5 months (range, 16–58 months). Conclusion: New-onset seizures after OLT may herald fatal outcome, especially in patients with cerebrovascular disease or sepsis. The prognosis of seizures in survivors is excellent, and long-term antiepileptic drugs are not required in most cases.

Relationship between hypometabolic patterns and ictal scalp EEG patterns in patients with unilateral hippocampal sclerosis: An FDG―PET study

This study was to explore the relationship between scalp ictal EEG patterns and interictal hypometabolic patterns in hippocampal sclerosis-associated mesial temporal lobe epilepsy (HS-MTLE) and determine the clinical significance of interictal hypometabolic patterns. Twenty-five patients were classified into 2 groups based on initial ictal discharge (IID) frequency on scalp EEG: (a) those with a sustained regular 5- to 9-Hz rhythm with a restricted temporal or subtemporal distribution (group 1, N=9); and (b) those with an irregular 2- to 5-Hz rhythm with a widespread distribution (group 2, N=16). Using statistical parametric mapping, the PET results of each group were compared with age- and sex-matched controls to identify regions of significant hypometabolism, and the clinical characteristics were compared. Group 1 showed focal hypometabolism confined to the ipsilateral temporal lobe, whereas group 2 showed widespread hypometabolism in the ipsilateral temporal lobe, insular cortex and anterior part of the putamen. The two groups showed no significant differences in clinical characteristics. Among semiologic features, dystonic limb posturing was more frequently observed in group 2 (p=0.03). In summary, scalp EEG IID patterns in HS-MTLE can be important in determining hypometabolic patterns on interictal PET. Differences in hypometabolic patterns may reflect preferential pathways of ictal propagation rather than intrinsic epileptogenic regions.

Efficacy and safety of levetiracetam as adjunctive treatment of refractory partial seizures in a multicentre open-label single-arm trial in Korean patients

This prospective, open-label study evaluated the efficacy and safety of adjunctive levetiracetam (LEV) in Korean adults with uncontrolled partial epilepsy. Study patients had to have an average of at least 1 and not more than 14 partial seizures per month (averaged over a 3-month historical baseline) despite the use of one or two AEDs. Patients initially received LEV 1000 mg/day (administered bid) and could increase to 2000 mg/day after 2 weeks, and to 3000 mg/day after another 2 weeks, to obtain adequate seizure control. During the 12-week maintenance period, the dose of LEV could be increased or decreased once if seizure control was insufficient or tolerability warranted, respectively. Seizure count and adverse events (AEs) were recorded by patients. Global evaluation scale (GES) and quality of life (QOLIE-31) were also evaluated. A total of 100 patients were enrolled and 92 patients completed the study. The median percent reduction in weekly seizure frequency over the treatment period was 43.2%. The >or=50% and >or=75% responder rates were 45.4% and 36.1%, respectively. Seizure freedom throughout the 16-week treatment period was observed in 17 patients. On investigators GES, 81 patients were considered improved, with 41 patients showing marked improvement. Most QOLIE-31 scales improved significantly. Treatment-emergent AEs were reported in 59 patients. Three most common AEs were somnolence (36%), dizziness (12%), and headache (8%). Adjunctive LEV therapy was effective and well-tolerated in Korean adults with refractory partial epilepsy.

The Utility of Three Screening Questionnaires for Obstructive Sleep Apnea in a Sleep Clinic Setting

Purpose The aim of this study was to determine the diagnostic value of three screening questionnaires in identifying Korean patients at high risk for obstructive sleep apnea (OSA) in a sleep clinic setting in Korea. Materials and Methods Data were collected from 592 adult patients with suspected OSA who visited a sleep center. All patients completed the Sleep Apnea of Sleep Disorder Questionnaire (SA-SDQ), the Berlin questionnaire, and the STOP-Bang questionnaire. Estimated OSA risk was compared to a diagnosis of OSA. The sensitivity, specificity, positive predictive value, and negative predictive value were calculated for each questionnaire. Results The prevalence of OSA was 83.6% using an apnea-hypopnea index (AHI) ≥5/h and 58.4% for an AHI ≥15/h. The STOP-Bang questionnaire had a high sensitivity (97% for AHI ≥5/h, 98% for AHI ≥15/h), but the specificity was low (19% and 11%, respectively). In contrast, the sensitivity of the SA-SDQ was not high enough (68% for AHI ≥5/h, 74% for AHI ≥15/h) to be useful in a clinical setting, whereas the specificity was relatively good (66% and 61%, respectively). The sensitivity and specificity values of the Berlin questionnaire fell between those of the STOP-Bang questionnaire and the SA-SDQ. Conclusion The STOP-Bang questionnaire may be useful for screening OSA in a sleep clinic setting, but its specificity is lower than the acceptable level for this purpose. A new screening questionnaire with a high sensitivity and acceptable specificity is therefore needed in a sleep clinic setting.

Factors contributing to the development of perceived stigma in people with newly diagnosed epilepsy: A one-year longitudinal study

PURPOSE We evaluated the course of perceived stigma and the factors associated with perceived stigma over the first year in newly diagnosed people with epilepsy (PWE). METHODS We recruited newly diagnosed PWE from 12 tertiary hospitals in Korea. The perceived stigma of epilepsy was assessed using the Stigma Scale at baseline and one year later. At the time of diagnosis, demographic, clinical seizure-related, and psychological data were collected. The predictive factors for perceived stigma over one year were analyzed using logistic regression analyses. RESULTS Two hundred eighteen newly diagnosed PWE were included at baseline, and 153 completed the study. The percentage of participants who felt stigmatized decreased from 30.7% at the time of diagnosis to 17.6% at the end of follow-up. Introverted personality and a high level of anxiety were independent factors contributing to stigma at the time of epilepsy diagnosis. At the one-year follow-up, introverted personality and lower economic status were predictive of the development of perceived stigma. CONCLUSION Introverted personality was an important factor contributing to the development of perceived stigma at the time of diagnosis and at one year after diagnosis. In addition, a high level of anxiety and a low economic status were independently related to feelings of stigma at baseline and at one year after diagnosis, respectively. There may be a decrease in the perception of stigma over one year in newly diagnosed PWE.

Effect of interseizure interval on seizure lateralization in patients with bilateral seizure foci

We investigated whether there is a cluster effect depending on localization of seizure foci in patients with bilateral seizure foci. We evaluated 171 seizure pairs from 193 seizures recorded in 28 patients. Seizure lateralization was determined by the lateralization of ictal discharges; if the ictal EEG pattern was not lateralized, lateralization was determined by clinical seizure semiology. The logarithm of the interseizure interval (ISI) was significantly related to seizure concordance only in patients with extratemporal seizure foci, but not in those with bitemporal foci. In the former group, the mean ISI for concordant seizure pairs was significantly shorter than that for discordant seizures pairs (292 min versus 631 min, p=0.023). Seizure types composing seizure pairs had a significant influence on ISI regardless of the localization of seizure foci. ISIs were shortest in seizure pairs with only partial seizures. However, types of seizure pairs were significantly related to concordance rates of seizure lateralization only in patients with extratemporal foci (p=0.005). In conclusion, our results suggest that the cluster effect on seizure localization exists in patients with extratemporal seizure foci, but not in those with bitemporal foci.

Hydrocephalus and Hyponatremia as the Presenting Manifestations of Primary CNS Lymphoma

the cerebral convexity. He was then referred to our institution for further evaluation of presumed NPH. On admission, he was awake but apathetic and unmotivated. Vital signs were normal. He was confused and disoriented to time and place. He showed profound memory impairment and a MiniMental Status Examination read 5 out of 30. Cranial nerve, motor, sensory and refl ex functions were intact. Speech was slightly dysarthric and hypophonic. He was generally bradykinetic, accompanied by neither tremor nor rigidity. His gait disturbance was characterized by upright posture, widebased short steps, gait initiation diffi culty, shuffl ing, freezing and postural impairment. Routine blood works were normal except for mild hyponatremia (124 mmol/l). Serological tests for syphilis and AIDS were negative. Cerebrospinal fl uid (CSF) examination disclosed normal opening pressure, 3 white cells/mm 3 , normal glucose and elevated total protein (142 mg/dl). There were no malignant cells. Three consecutive therapeutic CSF drainages of approximately 70 ml failed to show any clinical improvement. Subsequent CSF tests for virus, tuberculosis, mycoplasma, syphilis, fungi and parasites were negative. One week after admission, he became drowsy and somnolent, with declining responsiveness. Marked hyponatremia (110 mmol/l) was noted and his Dear Sir, Although increasing incidence is reported, primary central nervous system lymphoma (PCNSL) is still uncommon in immunocompetent individuals. Accurate and timely diagnosis of PCNSL is often diffi cult because of its ambiguous clinical behaviors and inconsistent radiological fi ndings [1– 4] . We describe an unusual case of PCNSL whose clinical-radiological manifestations were fi rst suggestive of idiopathic normalpressure hydrocephalus (NPH) with hyponatremia.