Eun Yeon Joo

Sungkyunkwan University | SKKU · Department of Neurology

Background Sleep disorders, such as obstructive sleep apnea (OSA), comorbid insomnia and sleep apnea (COMISA), and insomnia are common and can have serious health consequences. However, accurately diagnosing these conditions can be challenging as a result of the underrecognition of these diseases, the time-intensive nature of sleep monitoring neces...

Objectives: To improve the adaptation of shift work, various flexible shift patterns for nurses have introduced in addition to the existing eight-hour-three-shift system. This study aimed to compare the differences in rotating nurses’ sleep characteristics according to shift patterns. Methods: A total of 62 rotating nurses (all females, mean age 29...

The prevalence of artificial light exposure has enabled us to be active any time of the day or night, leading to the need for high alertness outside of traditional daytime hours. To address this need, we developed a personalized sleep intervention framework that analyzes real-world sleep-wake patterns obtained from wearable devices to maximize aler...

Stridor is a rare but important non-motor symptom that can support the diagnosis and prediction of worse prognosis in multiple system atrophy. Recording sounds generated during sleep by video-polysomnography is recommended for detecting stridor, but the analysis is labor intensive and time consuming. A method for automatic stridor detection should...

Objective: Lateral temporal lobe epilepsy (LTLE) has been diagnosed in only a small number of patients; therefore, its surgical outcome is not as well-known as that of mesial temporal lobe epilepsy. We aimed to evaluate the long-term (5 years) and short-term (2 years) surgical outcomes and identify possible prognostic factors in patients with LTLE...

Objectives: Galaxy Watch 3 (GW3) is a commercially available smartwatch equipped with a sleep-tracking function capable of collecting longitudinal sleep data in a real-world environment. We aimed to investigate the validity of GW3 for estimating sleep stages compared with reference data from polysomnography (PSG).Methods: Thirty-two healthy adults...

Objectives: This study aimed to investigate group differences in demographic, clinical, and polysomnographic characteristics based on the presence or absence of excessive daytime sleepiness (EDS) and insomnia symptoms.Methods: In this retrospective study, patients were divided into five groups based on their Epworth Sleepiness Scale and Insomnia Se...

Background and Objective Obstructive sleep apnea (OSA) has significant effects on quality of life and may lead to cognitive impairments. Continuous positive airway pressure (CPAP) is the standard treatment for OSA and has been shown to improve sleep disturbances and daytime dysfunction. In this study, we aimed to assess the effects of CPAP on white...

Obstructive sleep apnea (OSA) may lead to white mater (WM) disruptions and cognitive deficits. However, no studies have investigated the full extent of the brain WM, and its associations with cognitive deficits in OSA remain unclear. We thus applied diffusion tensor imaging (DTI) tractography with multi-fiber models and used atlas-based bundle-spec...

BACKGROUND Sleep disorders, such as obstructive sleep apnea (OSA), comorbid insomnia and sleep apnea (COMISA), and insomnia are common and can have serious health consequences. However, accurately diagnosing these conditions can be challenging as a result of the underrecognition of these diseases, the time-intensive nature of sleep monitoring neces...

Stridor is a rare but important non-motor symptom that can support the diagnosis and prediction of worse prognosis in multiple system atrophy. Recording sounds generated during sleep by video-polysomnography is recommended for detecting stridor, but the analysis is labor intensive and time consuming. A method for automatic stridor detection should...

Rapid eye movement (REM) sleep behavior disorder (RBD) is characterized by complex motor behaviors and REM without atonia. RBD shows diverse clinical manifestations, ranging from typical violent dreamenacting behaviors to relatively subtle limb movements. Sleep disorders such as obstructive sleep apnea (OSA) and nocturnal seizure that mimic RBD sym...

Objectives: The aim of this study was to evaluate dizziness in patients with sleep disorders, objectively identify vestibular function through the vestibulo-ocular reflex (VOR) using the video Head Impulse Test (vHIT), and evaluate the association between these findings.Methods: Among the patients who visited the sleep clinic from June to October 2...

Objectives: Nicotine stimulates release of neurotransmitters that regulate the sleep-wake cycle and thereby leads to insomnia. Smoking is associated with upper airway distress; however, its role in severe sleep-related breathing disorders remains controversial. In this study, we investigated the effects of smoking on obstructive sleep apnea (OSA).M...

Sleep architecture and microstructures alter with aging and sleep disorder-led accelerated aging. We proposed a sleep EEG based brain age prediction model using convolutional neural networks. We then associated the estimated brain age index with brain structural aging features, sleep disorders and various sleep parameters. Our model also showed a h...

Objectives: Insomnia is a disorder that involves poor sleep quality at nighttime and various symptoms in the daytime. Although it is known to increase cardiovascular risk as well as psychiatric comorbidities such as depression and anxiety, less attention has been paid to daytime sleepiness in patients with insomnia. This study aimed to investigate...

Objectives: Carbon dioxide (CO₂) accumulation in an enclosed space might cause drowsiness. This study aimed to assess the effect of bedtime exposure to low concentrations of CO₂ gas on the sleep quality of adults with insomnia.Methods: In this double-blind, randomized, sham-controlled cross-over study, we consecutively recruit...

Obstructive sleep apnea (OSA) and dizziness are common conditions observed in the general population, and several epidemiological studies have reported an association between OSA and dizziness. Vestibular dysfunction, autonomic instability, and cerebellar degeneration secondary to recurrent hypoxia are implicated as mechanisms underlying dizziness...

Low health-related quality of life (HRQOL) is associated with adverse outcomes in diabetic kidney disease (DKD) patients. We examined the modifiable factors associated with low HRQOL in these patients. We enrolled 141 DKD patients. HRQOL was assessed with the Short Form 36 (SF-36) questionnaire. Low HRQOL was defined as a score > one standard devia...

Objectives To characterize and evaluate the estimation of oxygen saturation measured by a wrist-worn reflectance pulse oximeter during sleep. Methods Ninety-seven adults with sleep disturbances were enrolled. Oxygen saturation was simultaneously measured using a reflectance pulse oximeter (Galaxy Watch 4 [GW4], Samsung, South Korea) and a transmit...

This study aims to compare directed transfer function (DTF), which is an effective connectivity analysis, derived from scalp EEGs between responder and nonresponder groups implanted with vagus-nerve stimulation (VNS). Twelve patients with drug-resistant epilepsy (six responders and six nonresponders) and ten controls were recruited. A good response...

Background: Sleep stage scoring, which is an essential step in the quantitative analysis of sleep monitoring, relies on human experts and is therefore subjective and time-consuming; thus, an easy and accurate method is needed for the automatic scoring of sleep stages. Methods: In this study, we constructed a deep convolutional recurrent (DCR) mo...

Objectives: This study aimed to investigate the prevalence of symptoms of shift work disorder (SSWD) and its related factors in rapidly rotating three-shift nurses. Methods: We enrolled 344 nurses (mean age, 28.7 years) without prior history of sleep disturbance before starting shift work in a university-affiliated hospital. SSWD were defined using...

Objectives: This study aims to examine the clinical differences between objective short sleep insomniacs (OSSI) and subjective short sleep insomniacs (SSSI). Methods: We enrolled 79 patients (aged 27–74 years) with chronic insomnia disorder (CID) who underwent overnight polysomnography (PSG) and completed sleep-related questionnaires as well as hab...

Objectives: Many patients with obstructive sleep apnea syndrome (OSAS) have nocturia. However, the predictive index of nocturia in patients with OSAS is currently not well known. We aimed to investigate the prevalence of nocturia in patients with OSAS and determine the factors that could predict nocturia in these patients. Methods: In this retro...

We explored the associations of actigraphy-derived rest-activity patterns and circadian phase parameters with clinical symptoms and level 1 polysomnography (PSG) results in patients with chronic insomnia to evaluate the clinical implications of actigraphy-derived parameters for PSG interpretation. Seventy-five participants underwent actigraphy asse...

Background: Several studies have reported the efficacy of intravenous (IV) iron for patients with restless legs syndrome (RLS), but little is known about the efficacy or safety of repeated IV iron treatment. The aim of this study was to evaluate the effectiveness of repeated doses of IV ferric carboxymaltose (FCM) in treating RLS symptoms. Method...

Sleep architecture and microstructures alter with aging and sleep disorder-led accelerated aging. We proposed a sleep electroencephalogram (EEG) based brain age prediction model using convolutional neural networks. We then associated the estimated brain age index (BAI) with brain structural aging features, sleep disorders and various sleep paramete...

Objectives: Sleep issues are more prevalent in healthcare workers compared to workers in other industries. This study investigated sleep-wake pattern, sleep quality, and daytime status in hospital workers using a Galaxy Watch3 (GW3), a wrist-worn device that uses an accelerometer and heart rate sensor to distinguish sleep and wakefulness.Methods: M...

BACKGROUND Obstructive sleep apnea (OSA) is a common sleep disorder characterized by repetitive upper airway obstruction during sleep, thereby resulting in oxygen desaturation, frequent arousals, and increased sympathetic activity. Wearable devices that measure peripheral oxygen saturation have been developed for the screening of OSA. OBJECTIVE Th...

Healthy sleep is an essential physiological process for every individual to live a healthy life. Many sleep disorders both destroy the quality and decrease the duration of sleep. Thus, a convenient and accurate detection or classification method is important for screening and identifying sleep disorders. In this study, we proposed an AI-enabled alg...

We proposed a sleep EEG-based brain age prediction model which showed higher accuracy than previous models. Six-channel EEG data were acquired for 6 hours sleep. We then converted the EEG data into 2D scalograms, which were subsequently inputted to DenseNet used to predict brain age. We then evaluated the association between brain aging acceleratio...

We explored the associations of actigraphy-derived rest-activity patterns and circadian phase parameters with clinical symptoms and level 1 polysomnography (PSG) results in patients with chronic insomnia to evaluate the clinical implications of actigraphy-derived parameters for PSG performance. Seventy-five participants underwent actigraphy assessm...

Shift workers and many other groups experience irregular sleep-wake patterns. This can induce excessive daytime sleepiness that decreases productivity and elevates the risk of accidents. However, the degree of daytime sleepiness is not correlated with standard sleep parameters like total sleep time, suggesting other factors are involved. Here, we a...

Study Objectives Previous functional MRI studies have reported altered brain networks in patients with obstructive sleep apnea (OSA). However, the extent and pattern of abnormal connectivity were inconsistent across studies, and cerebrocerebellar connections have been rarely assessed. We investigated functional network changes in cerebral and cereb...

Levetiracetam is a new antiepileptic drug (AED) used for treating and preventing partial or generalized seizures. The usefulness of levetiracetam therapeutic drug monitoring (TDM) is related to inter- or intra-individual pharmacokinetic variability, drug interactions, and patient noncompliance. We aimed to investigate the levetiracetam TDM status i...

Prior diffusion tensor imaging (DTI) studies have investigated white matter (WM) changes in patients with primary restless legs syndrome (RLS), but the results were inconsistent. Here, we proposed using tract-specific statistical analysis (TSSA) to find alterations in specific WM tracts to clarify the pathophysiological mechanisms of RLS. We enroll...

BACKGROUND Healthy sleep is an essential and important physiological process for every individual to live a healthy life. Many sleep disorders are both destroying the quality and decreasing the duration of sleep. Thus, a convenient and accurate detection or classification method is important for screening and identifying sleep disorders. OBJECTIVE...

Background and objective: Subtraction of ictal SPECT coregistered to MRI (SISCOM) provides complementary information for detecting the ictal onset zone, especially in patients with MRI-negative focal epilepsy, and provides additional useful information for predicting long-term postresection outcomes. This study sought to investigate the relationsh...

Objective: Organic light-emitting diodes (OLEDs) emit less blue light than traditional light-emitting diodes (LEDs), and we previously found that early-night OLED light exposure (LE) delays the melatonin phase by less than LED at a color temperature of 4,000 K. As a follow-up study, we investigated the effects of OLED and LED at a different color...

Introduction Using deep learning algorithms, we investigated univariate and multivariate effects of four polysomnography features including heart rate (HR), electrocardiogram (ECG), oxygen saturation (SpO2) and nasal air flow (NAF) on the identification of sleep apnea and hypopnea events. This explanatory analysis that may clarify the sensitivity a...

Altered cerebral perfusion has been reported in obstructive sleep apnea (OSA). Using dynamic susceptibility contrast MRI, we compared cerebral perfusion between male OSA patients and male healthy reference subjects and assessed correlations of perfusion abnormalities of OSA patients with sleep parameters and neuropsychological deficits at 3 T MRI,...

Objective Focal cortical dysplasia (FCD) represents a heterogeneous group of disorders of the cortical formation and is one of the most common causes of epilepsy. Magnetic resonance imaging (MRI) is the modality of choice for detecting structural lesions, and the surgical prognosis in patients with MR lesions is favorable. However, the surgical pro...

Background and purpose: Obesity is known of one of the risk factors for obstructive sleep apnea (OSA). Although body mass index (BMI) can be an indicator for obesity, it does not represent the actual body composition of fat or muscle. We hypothesized that bioelectrical impedance analysis (BIA) can help analyze the fat and muscle distributions in m...

None: In multiple system atrophy (MSA), sleep-disordered breathing has a broad spectrum of phenotypes, among them inspiratory stridor and obstructive sleep apnea being most frequent. We present a case of 59-year old female with cerebellar-type MSA, who showed transient paradoxical breathing effort during non-REM sleep on diagnostic polysomnography...

Shift workers and many other groups experience irregular sleep-wake patterns. This can induce excessive daytime sleepiness that decreases productivity and elevates the risk of accidents. However, the degree of daytime sleepiness is not correlated with standard sleep parameters like total sleep time, suggesting other factors are involved. Here, we a...

Melatonin and cortisol are clinically important for diagnosing sleep and mood disorders. We developed and validated a liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay for simultaneous measurement of salivary melatonin and cortisol concentrations according to the Clinical and Laboratory Standards Institute guidelines. Additionally, we...

Background: This paper proposes a novel method for automatically identifying sleep apnea (SA) severity based on deep learning from a short-term normal electrocardiography (ECG) signal. Methods: A convolutional neural network (CNN) was used as an identification model and implemented using a one-dimensional convolutional, pooling, and fully connec...

Background and Objectives: Amyloid-beta protein may lead to sleep disturbance and eventually develop cognitive impairment. Idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD) is a predictor of neurodegeneration, yet there have been limited studies evaluating the relationship between cognitive decline and amyloid accumulation in iRBD...

Background Sleep technicians are at high risk of shift work sleep disorders. We therefore aimed to identify the optimal shift system for sleep technicians. Methods We performed a nationwide survey of the work schedules, health and quality of life of sleep technicians using e-mail questionnaires including the Insomnia Severity Index (ISI), Epworth...

Background and Objective Our objective in this study was to investigate gender-specific differences in demographic factors, clinical presenting symptoms, medical comorbidities, and sleep-related parameters in patients newly diagnosed with obstructive sleep apnea (OSA). Methods We enrolled patients who were more than 30 years old, had undergone over...

White matter alterations related to hypocretin pathway have been less evaluated in patients who have narcolepsy with cataplexy (NC), as compared to the identified exploration of gray matter and have varied among structural brain magnetic resonance imaging studies. The aim of this study was to investigate the disruption of specific white matter trac...

Purpose: The significance of interictal epileptiform discharges (IEDs) observed in the extratemporal lobe has not been fully evaluated in patients with mesial temporal lobe epilepsy (MTLE). This study aimed to evaluate the surgical outcomes, clinical features, and functional neuroimaging characteristics of patients in relation to the presence or a...

Purpose The aim of this study is to determine the impact of myofunctional therapy support program (MTSP) based on self-efficacy theory compared to no support during myofunctional therapy (MT) in patients with obstructive sleep apnea (OSA). Methods Thirty-one patients with OSA were randomized into two groups: 12 weeks of treatment with the MTSP dev...

Background and purpose: Organic light-emitting diodes (OLEDs) emit less blue light than traditional light-emitting diodes (LEDs), but the effects of OLED light exposure (LE) on melatonin and sleep have not been evaluated. Methods: Twenty-four healthy subjects (age 26.9±5.7 years; including 18 females) with the intermediate chronotype were expose...

OBJECTIVE The anterior thalamic nucleus (ATN) is a common target for deep brain stimulation (DBS) for the treatment of drug-refractory epilepsy. However, no atlas-based optimal DBS (active contacts) target within the ATN has been definitively identified. The object of this retrospective study was to analyze the relationship between the active conta...

Background and purpose: Sleep disturbance is common in patients with primary headache disorders. We were interest in whether poor sleep quality affects patients directly or via increases in the frequency and severity of headaches. To that end, we investigated the direct and indirect effects of sleep quality on the headache-related impact among pat...

Background Significant benefit of intravenous ferric carboxymaltose (FCM) treatment for restless legs syndrome (RLS) has been well-established. However, no clinical indicators predicting treatment response of RLS have been established. This study aimed to determine factors predicting outcome of clinical FCM treatment of RLS patients. Methods Data...

Narcolepsy with cataplexy is characterized by excessive daytime sleepiness, cataplexy, and other REM sleep phenomena. Previous MRI studies were cross-sectional in design and could not adequately address if disease progression leads the brain structural abnormalities in narcolepsy. Our analysis in patients using longitudinally collec