Otoconial Degeneration After Transient Ischemia Induced by Four-Vessel Occlusion in Rats

Background@#and Purpose Ischemia of the inner ear may damage the otoconia. However, no study has explored any changes in the configuration of otoconia after transient ischemia of the labyrinth. @*Methods@#Nineteen 7-week-old Sprague-Dawley rats were randomly assigned to either the sham (n=5) or the experimental group (n=14). The rats in the experimental group were subjected to global ischemia for 20 minutes using a four-vessel occlusion model, and were sacrificed seven days after the procedure. The rats in the sham group were sacrificed without any procedure. The otolithic organs (utricle and saccule) were dissected out for scanning electron microscope. @*Results@#The otolithic organs in the sham group showed their normal gross configuration with a dense clumping of otoconia with a normal hexagonal morphology and a smooth surface. The otolithic organs in the experimental group also maintained a grossly normal configuration, but each otoconia showed irregular surfaces with numerous cracks or furrows, especially in the periphery of the otoconial bed. @*Conclusions@#The current study showed that otoconial degeneration may occur even after transient ischemia of the labyrinth. This finding supports an association between cerebral ischemia and benign paroxysmal positional vertigo.

Clinical Significance of Redundant Nerve Roots of the Cauda Equina in Spine MRI

Purpose@#This study aimed to evaluate the association of redundant nerve roots of the cauda equina (RNRCEs) with the degree and duration of symptoms in patients with lumbar spinal canal stenosis. @*Materials and Methods@#Between January 2017 and December 2018, 224 patients demonstrating central canal stenosis on lumbar spine MRI were included. Various imaging findings associated with spinal canal stenosis were investigated, as were the presence, level, type, and length of RNRCEs, and the presence of nerve root swelling. Clinically, the degree of symptoms and symptom changes after treatment were investigated. Multinomial logistic regression was used for statistical analysis. @*Results@#RNRCEs were present in 142 patients (63.4%). Most RNRCEs were observed above the level of stenosis (47.3%). RNRCE was associated with the number of stenoses and symptom duration (p < 0.05). The presence, level, type, and length of RNRCE and nerve root swelling significantly affected the severity of symptoms (p < 0.05). The type of treatment influenced symptom changes (p < 0.05). @*Conclusion@#The recognition and assessment of RNRCEs on spinal MRI are clinically important because the presence, level, type, and length of a RNRCE may be associated with the degree of symptoms and help predict the clinical outcome according to treatment methods.

Milk Consumption and Bone Mineral Density in Adults: Using Data from the Korea National Health and Nutrition Examination Survey 2008–2011 / 가정의학회지

Background@#Milk consumption is associated with bone mineral density (BMD), but reports are limited in terms of participant age, sex, and number of study subjects. We investigated the association between milk consumption and BMD in South Korean adults (≥20 years). @*Methods@#We analyzed men and women aged ≥20 years who participated in the Korean National Health and Nutrition Examination Survey, 2008–2011. We used linear regression to calculate the mean BMD and 95% confidence interval (CI) based on the frequency of milk consumption. Multivariate logistic regression analysis was used to estimate the odds ratios (ORs) and 95% CI for T-scores ≤-2.5 (osteoporosis) in both men aged ≥50 years and postmenopausal women. @*Results@#In total 8,539 subjects were studied. Drinking milk more than once a day was associated with higher BMD in the total femur and femoral neck in men aged <50 years and lumbar spine in men aged ≥50 years, compared to less than once a week. It was also associated with lower ORs for osteoporosis of the femoral neck and lumbar spine in men aged ≥50 years (OR, 0.35; 95% CI, 0.125–0.979 and OR, 0.34; 95% CI, 0.143–0.804, respectively). In postmenopausal women who consumed milk 2–6 times weekly, higher BMD and lower OR for osteoporosis were observed in the total femur (OR, 0.23; 95% CI, 0.055–0.958). @*Conclusion@#This study suggests that frequent milk consumption could potentially reduce osteoporosis incidence in South Korean adults. Further prospective study is necessary to elucidate the effect of milk consumption on BMD.

Significant Domains of Life Satisfaction That Affect Suicidal Behavior in Adolescents

Objectives@#Adolescent suicide is a serious national issue in Korea. Recently, life satisfaction has been recognized as a major factor related to this issue. The main purpose of this study was to identify the domains of life satisfaction that affect suicidal behavior in adolescence. @*Methods@#Data were collected from eight middle schools in Incheon, Korea. A total of 1297 students answered questions regarding their demographic characteristics, happiness, self-related life satisfaction domains (appearance, leisure time, physical health, and mental health), depressive symptoms, and suicidal behavior. @*Results@#In the Spearman correlation analysis, female sex, perceived socioeconomic status (SES), happiness, and all four self-related satisfaction scores showed significant correlations with depression and suicidality. Multivariate regression analysis suggested that suicidality was significantly affected by perceived SES, satisfaction with appearance, mental health satisfaction, and depression. Finally, depression was identified as a partial mediator of the association between mental health satisfaction and suicidality, and a complete mediator of the association between female sex and suicidality. @*Conclusion@#Perceived SES, satisfaction with appearance, and mental health satisfaction significantly affected students’ suicidality, with or without the effect of depression. Health authorities, educators, and family members must be aware of this to identify adolescents at suicide risk earlier.

The Nationwide Incidence of Retinal Vein Occlusion Following Dialysis due to End-stage Renal Disease in Korea, 2004 through 2013

Background@#We investigated the incidence and risk of retinal vein occlusion (RVO) in endstage renal disease (ESRD) patients on dialysis in Korea. @*Methods@#In this nationwide cohort study, we used Korean National Health Insurance Service data between 2004 and 2013 for analysis. ESRD patients who started dialysis from 2004 to 2013 and an equal number of controls were selected through propensity score matching. RVO incidence in both cohorts were calculated for 2004–2013 using washout data from 2003. The multivariable Cox proportional hazards model was used to assess the risk of RVO in dialysis cohort. The Kaplan-Meier method was used to generate the cumulative RVO incidence curve.Whether the dialysis modality affects the development of RVO was also evaluated. @*Results@#In this study, 74,551 ESRD patients on dialysis and the same number of controls were included. The incidence of RVO was significantly higher in the dialysis cohort than in the control cohort (dialysis = 7.3/1,000 person-years [PY]; control = 1.9/1,000 PY; P < 0.001). The cumulative-incidence of RVO was also significantly higher in the dialysis cohort than in the control cohort (P < 0.001; log-rank test). However, there was no significant difference in the incidence of RVO between the two dialysis methods (P = 0.550; log-rank test). @*Conclusion@#This study provided epidemiological evidence that receiving dialysis for ESRD could increase the risk of developing RVO. We also found a rapid increase in the incidence of RVO with a longer dialysis period. These results strengthen the relationship between retinal vascular disease and renal function.

Diagnostic Value of Straight Head Hanging in Posterior Canal Benign Paroxysmal Positional Vertigo

Background@#and PurposeTo determine the diagnostic value of straight head hanging (SHH) in benign paroxysmal positional vertigo involving the posterior semicircular canal (PC-BPPV). @*Methods@#We retrospectively included 62 patients (age=56.2±15.0 years, 47 female) with unilateral PC-BPPV who underwent both the Dix-Hallpike maneuver and SHH before receiving canalith repositioning therapy (CRT) between September 2017 and July 2020 at the Dizziness Center of Seoul National University Bundang Hospital in South Korea (16 patients, 25.8%) or the Neurology Outpatient Clinic of Aerospace Central Hospital in China (46 patients, 74.2%). SHH was performed before (n=29, group A) or after (n=33, group B) the Dix-Hallpike maneuver. @*Results@#Torsional upbeat nystagmus typical of PC-BPPV was induced during SHH in 52 (83.9%) patients, and the incidence of this type of positional nystagmus did not differ between the groups A and B (79.3% vs. 87.9%, p=0.569). The maximum slow-phase velocity of the induced upbeat nystagmus was higher during SHH than during the Dix-Hallpike maneuver toward the lesion side [range=2.0–60.0°/s (median=18.5°/s) vs. range=2.7–40.0°/s (median=13.4°/s), p<0.001]. Reversal of the positional nystagmus was observed upon resuming the sitting position after SHH in 47 (75.8%) patients and after the Dix-Hallpike maneuver in 54 (87.7%) patients, with no significant difference between the groups (p=0.082). @*Conclusions@#SHH is effective for diagnosing PC-BPPV. Given its simplicity, SHH may be performed before the Dix-Hallpike maneuver, and CRT may be attempted thereafter when the typical positional nystagmus for unilateral PC-BPPV is induced during SHH.

Update on Nystagmus and Other Ocular Oscillations

This review reports on recent advances in understanding nystagmus and other involuntary eye movements. Advances in quantitative evaluations of eye movements using oculography, computational model simulations, genetics, and imaging technologies have markedly improved our understanding of the pathophysiology of involuntary eye movements, as well as their diagnosis and management. Patient-initiated capture of eye movements, especially when paroxysmal, and the online transfer of these data to clinicians would further enhance the ability to diagnose involuntary eye movements.

Milk Consumption and Bone Mineral Density in Adults: Using Data from the Korea National Health and Nutrition Examination Survey 2008–2011 / 가정의학회지

Background@#Milk consumption is associated with bone mineral density (BMD), but reports are limited in terms of participant age, sex, and number of study subjects. We investigated the association between milk consumption and BMD in South Korean adults (≥20 years). @*Methods@#We analyzed men and women aged ≥20 years who participated in the Korean National Health and Nutrition Examination Survey, 2008–2011. We used linear regression to calculate the mean BMD and 95% confidence interval (CI) based on the frequency of milk consumption. Multivariate logistic regression analysis was used to estimate the odds ratios (ORs) and 95% CI for T-scores ≤-2.5 (osteoporosis) in both men aged ≥50 years and postmenopausal women. @*Results@#In total 8,539 subjects were studied. Drinking milk more than once a day was associated with higher BMD in the total femur and femoral neck in men aged <50 years and lumbar spine in men aged ≥50 years, compared to less than once a week. It was also associated with lower ORs for osteoporosis of the femoral neck and lumbar spine in men aged ≥50 years (OR, 0.35; 95% CI, 0.125–0.979 and OR, 0.34; 95% CI, 0.143–0.804, respectively). In postmenopausal women who consumed milk 2–6 times weekly, higher BMD and lower OR for osteoporosis were observed in the total femur (OR, 0.23; 95% CI, 0.055–0.958). @*Conclusion@#This study suggests that frequent milk consumption could potentially reduce osteoporosis incidence in South Korean adults. Further prospective study is necessary to elucidate the effect of milk consumption on BMD.

Tinnitus Update

This article provides an update on tinnitus for audiologists and other clinicians who provide tinnitus-specific services. Tinnitus can be attributable to hearing loss, somatosensory system dysfunction, or auditory cortex dysfunction, with hearing loss being the most common cause and serious underlying pathologies being rare. Hearing loss does not always lead to tinnitus, and patients with tinnitus do not always suffer from hearing loss. The first scenario is explained by a so-called inhibitory gating mechanism, whereas the second assumes that all tinnitus sufferers have some degree of hearing impairment, which might not be detected in standard audiological examinations. The treatments should aim at symptomatic relief and management of associated distress. Current treatment options include pharmacotherapy, education, counseling, cognitive behavioral therapy, and sound therapy.

The Nationwide Incidence of Retinal Vein Occlusion Following Dialysis due to End-stage Renal Disease in Korea, 2004 through 2013

Background@#We investigated the incidence and risk of retinal vein occlusion (RVO) in endstage renal disease (ESRD) patients on dialysis in Korea. @*Methods@#In this nationwide cohort study, we used Korean National Health Insurance Service data between 2004 and 2013 for analysis. ESRD patients who started dialysis from 2004 to 2013 and an equal number of controls were selected through propensity score matching. RVO incidence in both cohorts were calculated for 2004–2013 using washout data from 2003. The multivariable Cox proportional hazards model was used to assess the risk of RVO in dialysis cohort. The Kaplan-Meier method was used to generate the cumulative RVO incidence curve.Whether the dialysis modality affects the development of RVO was also evaluated. @*Results@#In this study, 74,551 ESRD patients on dialysis and the same number of controls were included. The incidence of RVO was significantly higher in the dialysis cohort than in the control cohort (dialysis = 7.3/1,000 person-years [PY]; control = 1.9/1,000 PY; P < 0.001). The cumulative-incidence of RVO was also significantly higher in the dialysis cohort than in the control cohort (P < 0.001; log-rank test). However, there was no significant difference in the incidence of RVO between the two dialysis methods (P = 0.550; log-rank test). @*Conclusion@#This study provided epidemiological evidence that receiving dialysis for ESRD could increase the risk of developing RVO. We also found a rapid increase in the incidence of RVO with a longer dialysis period. These results strengthen the relationship between retinal vascular disease and renal function.

Diagnostic Value of Straight Head Hanging in Posterior Canal Benign Paroxysmal Positional Vertigo

Background@#and PurposeTo determine the diagnostic value of straight head hanging (SHH) in benign paroxysmal positional vertigo involving the posterior semicircular canal (PC-BPPV). @*Methods@#We retrospectively included 62 patients (age=56.2±15.0 years, 47 female) with unilateral PC-BPPV who underwent both the Dix-Hallpike maneuver and SHH before receiving canalith repositioning therapy (CRT) between September 2017 and July 2020 at the Dizziness Center of Seoul National University Bundang Hospital in South Korea (16 patients, 25.8%) or the Neurology Outpatient Clinic of Aerospace Central Hospital in China (46 patients, 74.2%). SHH was performed before (n=29, group A) or after (n=33, group B) the Dix-Hallpike maneuver. @*Results@#Torsional upbeat nystagmus typical of PC-BPPV was induced during SHH in 52 (83.9%) patients, and the incidence of this type of positional nystagmus did not differ between the groups A and B (79.3% vs. 87.9%, p=0.569). The maximum slow-phase velocity of the induced upbeat nystagmus was higher during SHH than during the Dix-Hallpike maneuver toward the lesion side [range=2.0–60.0°/s (median=18.5°/s) vs. range=2.7–40.0°/s (median=13.4°/s), p<0.001]. Reversal of the positional nystagmus was observed upon resuming the sitting position after SHH in 47 (75.8%) patients and after the Dix-Hallpike maneuver in 54 (87.7%) patients, with no significant difference between the groups (p=0.082). @*Conclusions@#SHH is effective for diagnosing PC-BPPV. Given its simplicity, SHH may be performed before the Dix-Hallpike maneuver, and CRT may be attempted thereafter when the typical positional nystagmus for unilateral PC-BPPV is induced during SHH.

Update on Nystagmus and Other Ocular Oscillations

This review reports on recent advances in understanding nystagmus and other involuntary eye movements. Advances in quantitative evaluations of eye movements using oculography, computational model simulations, genetics, and imaging technologies have markedly improved our understanding of the pathophysiology of involuntary eye movements, as well as their diagnosis and management. Patient-initiated capture of eye movements, especially when paroxysmal, and the online transfer of these data to clinicians would further enhance the ability to diagnose involuntary eye movements.

Significant Domains of Life Satisfaction That Affect Suicidal Behavior in Adolescents

Objectives@#Adolescent suicide is a serious national issue in Korea. Recently, life satisfaction has been recognized as a major factor related to this issue. The main purpose of this study was to identify the domains of life satisfaction that affect suicidal behavior in adolescence. @*Methods@#Data were collected from eight middle schools in Incheon, Korea. A total of 1297 students answered questions regarding their demographic characteristics, happiness, self-related life satisfaction domains (appearance, leisure time, physical health, and mental health), depressive symptoms, and suicidal behavior. @*Results@#In the Spearman correlation analysis, female sex, perceived socioeconomic status (SES), happiness, and all four self-related satisfaction scores showed significant correlations with depression and suicidality. Multivariate regression analysis suggested that suicidality was significantly affected by perceived SES, satisfaction with appearance, mental health satisfaction, and depression. Finally, depression was identified as a partial mediator of the association between mental health satisfaction and suicidality, and a complete mediator of the association between female sex and suicidality. @*Conclusion@#Perceived SES, satisfaction with appearance, and mental health satisfaction significantly affected students’ suicidality, with or without the effect of depression. Health authorities, educators, and family members must be aware of this to identify adolescents at suicide risk earlier.

Preventive effect of a 18-year water fluoridation program for dental caries in a rural area of Korea / 대한구강보건학회지

Objectives@#The water fluoridation program in Hapcheon township area has been implemented since 2000. This study aimed to evaluate the caries-preventive effect of water fluoridation on permanent teeth after implementation of an 18-year community water fluoridation program in a suburban area. @*Methods@#A survey was conducted in 2018 with 359 subjects, aged 8, 10, and 12 years, residing in the Hapcheon township area. In this prospective cohort study, the data on caries prevalence obtained from 671 subjects, aged 8, 10, and 12 years, in 2000, when the community water fluoridation program was initiated in the township, were used as a cohort to evaluate the caries-preventive effect after 18 years. The caries-preventive effect of community water fluoridation on permanent teeth was estimated by comparison of the adjusted DMFT scores between the program and the control group, and between the pre- and post-program data after 18 years. The confounding factor, mean number of fissure-sealed teeth, was adjusted to estimate the caries-preventive effect of fluoridation on permanent teeth. @*Results@#Based on the results of the surveys conducted in Hapcheon-eup in 2000 and 2018, the mean number of fissure-sealed permanent teeth was 2.24 in 2000 and 1.38 in 2018. The mean DMFT scores of subjects aged 8, 10, and 12 years in 2018, adjusted for fissure-sealed permanent teeth in the fluoridated area, were significantly lower than those reported by the 2018 Korea National Children’s Oral Health Survey. In addition, the mean values of the adjusted DMFT scores of subjects aged 8, 10, and 12 years in 2018, after the 18-year fluoridation program, were significantly lower than those reported in 2000, the year the fluoridation program was initiated. @*Conclusions@#Community water fluoridation has a high caries-reducing effect; thus, the reintroduction of water fluoridation program is desirable to prevent dental caries.

Preventive effect of a 18-year water fluoridation program for dental caries in a rural area of Korea / 대한구강보건학회지

Objectives@#The water fluoridation program in Hapcheon township area has been implemented since 2000. This study aimed to evaluate the caries-preventive effect of water fluoridation on permanent teeth after implementation of an 18-year community water fluoridation program in a suburban area. @*Methods@#A survey was conducted in 2018 with 359 subjects, aged 8, 10, and 12 years, residing in the Hapcheon township area. In this prospective cohort study, the data on caries prevalence obtained from 671 subjects, aged 8, 10, and 12 years, in 2000, when the community water fluoridation program was initiated in the township, were used as a cohort to evaluate the caries-preventive effect after 18 years. The caries-preventive effect of community water fluoridation on permanent teeth was estimated by comparison of the adjusted DMFT scores between the program and the control group, and between the pre- and post-program data after 18 years. The confounding factor, mean number of fissure-sealed teeth, was adjusted to estimate the caries-preventive effect of fluoridation on permanent teeth. @*Results@#Based on the results of the surveys conducted in Hapcheon-eup in 2000 and 2018, the mean number of fissure-sealed permanent teeth was 2.24 in 2000 and 1.38 in 2018. The mean DMFT scores of subjects aged 8, 10, and 12 years in 2018, adjusted for fissure-sealed permanent teeth in the fluoridated area, were significantly lower than those reported by the 2018 Korea National Children’s Oral Health Survey. In addition, the mean values of the adjusted DMFT scores of subjects aged 8, 10, and 12 years in 2018, after the 18-year fluoridation program, were significantly lower than those reported in 2000, the year the fluoridation program was initiated. @*Conclusions@#Community water fluoridation has a high caries-reducing effect; thus, the reintroduction of water fluoridation program is desirable to prevent dental caries.

Influence of Secondary Trauma Stress, and Vocation on Turnover Intention of Nurses in Regional Trauma Centers / 간호행정학회지

Eye Movements and Vestibulo-Ocular Reflex in Periventricular Leukomalacia

No abstract available.

Transient Homonymous Superior Quadrantanopsia in Nonketotic Hyperglycemia: A Case Report and Systematic Review

Background@#and Purpose: Nonketotic hyperglycemia often causes transient visual field defects, but only scattered anecdotes are available in the literature. @*Methods@#We report a patient with homonymous superior quadrantanopsia due to nonketotic hyperglycemia and provide a systematic literature review of the clinical features of 40 previously reported patients (41 in total, including our case) with homonymous visual field defects in association with nonketotic hyperglycemia. @*Results@#The typical visual field defect was congruous (84.6%), homonymous hemianopsia (87.8%) with macular splitting (61.5%) or sparing (38.5%). It was transient and repetitive in 54.5% of the patients, but it developed as a persistent form in the remainder. Positive visual symptoms such as hallucinations and phosphenes developed in 73.2% of patients. Brain MRI revealed corresponding abnormalities in most patients (84.8%), characterized by a low-intensity white-matter signal or a high-intensity gray-matter signal on T2-weighted or fluid-attenuated inversion recovery images with diffusion restriction or gadolinium enhancement. Most (97.0%) patients recovered completely, with 48.5% treated by glycemic control alone and the remainder also receiving antiepileptic agents. @*Conclusions@#Nonketotic hyperglycemia should be considered a possible cause of transient visual field defects, especially when it is associated with repetitive positive visual symptoms and typical MRI findings in hyperglycemic patients.

Neuro-ophthalmologic Findings in Visual Snow Syndrome

Background@#and Purpose: The findings of ophthalmic examinations have not been systematically investigated in visual snow syndrome. This study reviewed the abnormal neuroophthalmologic findings in a patient cohort with symptoms of visual snow syndrome. @*Methods@#We retrospectively reviewed 28 patients who were referred for symptoms of visual snow to a tertiary referral hospital from November 2016 to October 2019. We defined the findings of best corrected visual acuity (BCVA), visual field testing, pupillary light reflex, contrast sensitivity, full-field and multifocal electroretinography, and optical coherence tomography. @*Results@#Twenty patients (71%) were finally diagnosed as visual snow syndrome. Their additional visual symptoms included illusionary palinopsia (61%), enhanced entoptic phenomenon (65%), disturbance of night vision (44%), and photophobia (65%). A history of migraine was identified in ten patients (50%). The mean BCVA was less than 0.1 logarithm of the minimum angle of resolution, and electrophysiology showed normal retinal function in all patients. Contrast sensitivity was decreased in two of the seven patients tested. Medical treatment was applied to five patients which all turned out to be ineffective. Among the eight patients who were excluded, one was diagnosed with rod-cone dystrophy and another with idiopathic intracranial hypertension. @*Conclusions@#Neuro-ophthalmologic findings are mostly normal in patients with visual snow syndrome. Retinal or neurological diseases must be excluded as possible causes of visual snow.

Tacrolimus for Treating Orbital and Cranial Form of Idiopathic Inflammatory Pseudotumors

Background@#and Purpose: Orbital and cranial form of idiopathic inflammatory pseudotumors (IIPs) are rare disorders with heterogeneous clinical presentations. Corticosteroids have been the first-line treatment for IIPs, but they are not always effective. @*Methods@#We reviewed the medical records of three patients with orbital or cranial form of IIP who were treated with tacrolimus as an adjuvant treatment. @*Results@#The three patients showed favorable outcomes with the addition of tacrolimus, which is a calcineurin inhibitor that inhibits T-cell activation and T-cell-dependent B-cell activation. @*Conclusions@#Tacrolimus may be a safe and effective immunosuppressant for refractory or relapsing form of orbital or cranial IIPs.