Kyoung Jin Hwang

Regional white matter hyperintensities in normal aging, single domain amnestic mild cognitive impairment, and mild Alzheimer’s disease

Few studies have examined white matter hyperintensities (WMH) along the cognitive continuum between single-domain amnestic mild cognitive impairment (sd-aMCI) and Alzheimers disease (AD). The aims of our study were to explore relationships between the extent and location of WMH and disease severity along the cognitive continuum and to determine whether differences in the distribution of WMH could be predictive of specific patterns of cognitive impairment. We compared cognitive function, vascular risk factors, and regional (frontal lobe, parieto-occipital [PO] lobe, temporal lobe, periventricular [PV] white matter and deep white matter) WMH volume in 37 patients with mild AD, 23 patients with sd-aMCI, and 24 age-matched and education-matched normal controls. A quantitative volumetric method was applied to measure WMH burden. Total and regional WMH burdens, except for those in the temporal lobe, were significantly correlated with age (p<0.01). We found a trend toward increasing WMH volume with disease severity, higher in AD than in sd-aMCI and lowest in the controls. Total WMH volume was associated with the global cognitive test score. In multiple linear regression analysis, PV WMH volume, but not deep WMH volume, strongly predicted performances on the Controlled Oral Word Association test and the Color Word Stroop test after adjusting for important demographic variables. Only PO WMH volume was a significant predictor of a cognitive test score when frontal and temporal WMH volumes were simultaneously entered into the regression model. The extent and distribution of WMH, especially in the PV and PO regions, were associated with disease severity and reduced cognition.

Post-stroke restless leg syndrome and periodic limb movements in sleep.

Primary restless leg syndrome (RLS) and periodic limb movements in sleep (PLMS) frequently co‐exist, obscuring the boundaries between the two conditions. In such instances, a study of secondary cases with focal lesions such as post‐stroke RLS and PLMS (psRLS and psPLMS, respectively) can be helpful in identifying characteristics of the individual conditions.

Effects of Levetiracetam Monotherapy on the Cognitive Function of Epilepsy Patients

Aims: To estimate the effect of levetiracetam (LEV) on cognitive function and mood status in newly diagnosed epilepsy patients. Methods: Fifty-five drug-naïve epilepsy patients (M:F ratio = 31:24; mean age = 30.9 years) were included. All patients underwent two neuropsychological (NP) tests, one before receiving LEV and then another 12.9 ± 5.0 months after starting LEV monotherapy. We evaluated general cognitive function, verbal/visual attention and memory, linguistic and visuospatial functions, frontal lobe function, and mood status. Repeated-measures regression and generalized estimating equation models were applied to assess the effects of all the confounding variables such as seizure control, average LEV dose, duration of epilepsy, inter-test interval, and subtype of epilepsy syndrome. Results: LEV monotherapy over 1 year revealed significant improvements in the following domains of NP tests with the correction of possible confounding variables: verbal and visual attention, psychomotor speed, mental flexibility, executive function, verbal fluency and word generation. No NP domains showed any significant decrease. Conclusion: Our study suggested that LEV monotherapy had no harmful effect on cognitive function in drug-naïve patients with epilepsy.

Multiple microembolic brain infarctions in Clonorchis sinensis infestation

We report a case of multiple cerebral infarctions as the first symptom of hypereosinophilia with Clonorchis sinensis infestation. The patient showed hypereosinophilia and elevated cardiac enzyme, and the egg test of C. sinensis was positive. CT scans of the chest and the abdomen revealed eosinophilic infiltration in both lung and liver. Over a period of six weeks after praziquantel medication, he recovered. C. sinensis infestation which is endemic in East Asian countries should be considered as a cause of multiple microembolic stroke associated with idiopathic hypereosinophilic syndrome.

Diagonal Earlobe Crease is a Visible Sign for Cerebral Small Vessel Disease and Amyloid-β

We investigated the frequency and clinical significance of diagonal earlobe crease (DELC) in cognitively impaired patients using imaging biomarkers, such as white matter hyperintensities (WMH) on MRI and amyloid-β (Aβ) PET. A total of 471 cognitively impaired patients and 243 cognitively normal (CN) individuals were included in this study. Compared with CN individuals, cognitively impaired patients had a greater frequency of DELC (OR 1.6, 95% CI 1.1–2.2, P = 0.007). This relationship was more prominent in patients with dementia (OR 1.8, 95% CI 1.2–2.7, P = 0.002) and subcortical vascular cognitive impairment (OR 2.4, 95% CI 1.6–3.6, P < 0.001). Compared with Aβ-negative cognitively impaired patients with minimal WMH, Aβ-positive patients with moderate to severe WMH were significantly more likely to exhibit DELC (OR 7.3, 95% CI 3.4–16.0, P < 0.001). We suggest that DELC can serve as a useful supportive sign, not only for the presence of cognitive impairment, but also for cerebral small vessel disease (CSVD) and Aβ-positivity. The relationship between DELC and Aβ-positivity might be explained by the causative role of CSVD in Aβ accumulation.

The Difference in Heart Rate Change between Temporal and Frontal Lobe Seizures during Peri-ictal Period

Background and Purpose: Heart rate (HR) change is easily seen in seizures. Tachycardia is frequently seen in temporal lobe epilepsy (TLE), rather than extra temporal lobe epilepsy (XTLE). We report the difference in the HR pattern between TLE and frontal lobe epilepsy (FLE) during peri-ictal period. Methods: The ECG data, collected during EEG monitoring, was used. To compare the HR pattern between FLE and TLE, we investigated the baseline HR, maximum HR, seizure onset to peak HR, HR change, and the time return to baseline. Results: A total of 198 seizures (FLE was 115, TLE was 83) were included in this study. The baseline HR (in TLE, 74.9 ± 17.2 and in FLE, 70.7 ± 11.5 bpm), there was no difference between two groups. But the mean duration of the increased HR was more prolonged in TLE group (93.8 ± 54.9 seconds) than the FLE group(39.0 ± 21.4 seconds) (p < 0.001), the time to peak HR of the TLE group (135.1 ± 19.1 seconds) was higher than FLE group (119.3 ± 19.7 seconds) (p = 0.027), and the HR change of the TLE group (60.0 ± 26.3 bpm) was more prominent than that of the FLE group (22.8 ± 26.2 seconds) (p < 0.001). Furthermore, a longer duration of HR increase was seen in that of the TLE group than FLE group. Conclusions: The HR change of the TLE group was more prominent and prolonged than that of the FLE group. Therefore, the HR change can be a pattern that differentiates TLE from FLE.

Hematoma-Related Nonhabitual Seizures during Subdural Electrode Monitoring

Dear Editor, Epilepsy surgery is an established treatment in patients with drug-resistant epilepsy that can eliminate or significantly reduce the seizure frequency. Invasive EEG monitoring is an invaluable technique for localizing and delineating the affected parts of the cortex in surgery planning for patients with intractable partial epilepsy.1 However, invasive EEG monitoring has various complications related to the additional surgical procedures and the placement of foreign bodies in the brain or subdural space.2 A 31-year-old right-handed woman was admitted to the epilepsy clinic with drug-resistant seizures. She experienced frequent seizures consisting of a psychic aura, often progressing to loss of awareness and automatisms while taking oxcarbazepine and levetiracetam. Brain MRI showed a dysembryoplastic neuroepithelial tumor in the left temporal region. Interictal and ictal EEG showed that the maximum amplitude was over the left mesial temporal electrodes. Brain 18F-fluorodeoxyglucose positron-emission tomography revealed hypometabolism in the left anterior-to-posterior temporal region. A multidisciplinary epilepsy committee recommended invasive monitoring. A craniotomy was performed with left-sided subdural electrode grid placement, and 4× 5, 4×8, 1×8, and 4×5 contact grid electrodes were placed in the left frontotemporal region. We used platinum contact electrodes embedded in 0.5-mm-thick flexible silicone plates (AD-Tech Medical Instrument, Racine, WI, USA). Three depth electrodes were inserted into the hippocampus. The results of laboratory tests were normal, including the platelet count and prothrombin and partial thromboplastin times. Postoperative computed tomography showed no abnormalities other than the expected electrode artifacts. The patient experienced three habitual automotor seizures during the first 4 days after electrode placement. During these seizures the rhythmic activity started over the left hippocampal region and spread to the basal temporal area. At 6 days after electrode placement the patient reported acute-onset tingling sensations in the left temporal area and strange feelings lasting several minutes that she not experienced previously. These feelings recurred throughout the day, as often as several times per hour. During a nonhabitual episode, the EEG showed localized rhythmic activity involving electrodes K3-K4 and K8-K9 over the inferior frontal region, which were not previously involved in her habitual seizures (Fig. 1A). The subdural electrodes were removed 7 days after being placed, and a focal 3×2-cm well-formed hematoma was noted underlying the contacts of electrodes K3-K4 and K8-K9 over the suprasylvian frontal cortex (Fig. 1B). After evacuating the hematoma, slight indentations were evident in the underlying brain tissue, but there was no gross contusion or epileptiform discharge. An anterior temporal lobectomy with lesionectomy was performed. The mechanism of subgrid hematoma may involve a tear or avulsion of the bridging veins, similar to that of subdural hematoma. A space present between the grid and cortex Kyoung Jin Hwanga Eun Yeon Joob Seung Bong Hongb Dae Won Seob

Somatosensory reflex epilepsy: simultaneous video-EEG monitoring and surface EMG

Somatosensory reflex epilepsy is induced by repetitive cutaneous contact of a circumscribed body area with a tight time-lock between somatosensory stimulation and seizure. We describe the case of a 27-year-old man with seizures induced by repetitive tapping on the sole of the right foot. Simultaneous video-EEG monitoring and surface electromyography was performed during a seizure triggered by repetitive tapping on the right sole aspect using a hammer. Stimulation produced a tingling sensation on the right sole that extended to the right lower leg. This was followed by motor Jacksonian march of the right leg. [Published with video sequence on www.epilepticdisorders.com].

Sleep hygiene-related conditions in patients with mild to moderate obstructive sleep apnea

OBJECTIVE Sleep hygiene-related conditions are factors that affect the symptoms experienced by patients with obstructive sleep apnea (OSA). However, very few studies have investigated the association between sleep hygiene and sleep symptoms, especially in patients with mild or moderate OSA. This study evaluated the relationship between factors related to sleep hygiene and clinical symptoms in patients with mild to moderate OSA. METHODS One hundred and seventy-four patients who visited the Sleep Breathing Disorder Center at a tertiary academic center to evaluate suspected OSA were included. All patients underwent standard polysomnography (PSG) and the Epworth sleepiness scale (ESS) and questionnaires related to daytime and nighttime symptoms and sleep hygiene. Medical records were reviewed for demographic, clinical, and PSG parameters. Correlation analysis between sleep hygiene-related conditions and clinical symptoms in patients with mild to moderate OSA was performed. RESULTS The correlation analysis between the nine categories of sleep hygiene and the three categories of clinical symptoms showed that, in the case of inadequate temperature and humidity conditions, the three categories of clinical symptoms were more severe (daytime symptoms r=0.382, nighttime symptoms r=0.568, ESS score r=0.321). Drinking alcohol before sleep (daytime symptoms r=0.457, nighttime symptoms r=0.649, ESS score r=0.301) and emotional excitement or arousal (daytime symptoms r=0.378, nighttime symptoms r=0.545, ESS score r=0.341) were correlated with greater severity of each of the clinical symptoms (p<0.05). CONCLUSION Among the factors of sleep hygiene-related conditions, inadequate temperature and humidity, drinking alcohol before sleep, and emotional excitement or arousal were associated with symptoms of mild to moderate OSA. This study supports the hypothesis that patients with mild to moderate OSA can experience symptom relief if they are trained to correct lifestyle habits to maintain adequate sleep hygiene-related conditions.

Intractable Epilepsy with Solitary Cerebral Calcification

Cerebral calcification is a common incidental finding upon brain imaging and its epileptogenicity is often underestimated. Here, we report a case of intractable epilepsy arising in conjunction with a solitary cerebral calcification. A 42-year-old male with intractable epilepsy was admitted to the epilepsy clinic for invasive epilepsy surgery. Brain magnetic resonance imaging revealed a slight high-intensity signal change in the right amygdala and a small, calcified lesion in the right lateral temporal region. The patient underwent invasive monitoring with subdural electrodes. He had five habitual seizures with automatisms and fast activity. These seizures initiated in the right lateral temporal area just above the solitary calcified lesion. Neuropathology of the calcified lesion showed no specific findings apart from a fibrocalcific nodule. Thus, although solitary cerebral calcifications may be an asymptomatic or coincidental finding in some patients, they may also have a highly epileptogenic focus.