Seungbong Han

Alterations of mean diffusivity in brain white matter and deep gray matter in Parkinson's disease.

Although Parkinsons disease is a neurodegenerative disease primarily involving basal ganglia and midbrain, the deficit of white matter is also involved during the disease progression. As the diffusion tensor imaging method is sensitive to the microstructural changes, we investigated the microstructural alterations in white matter and deep gray matter in patients with Parkinsons disease. Brain images of 64 patients and sex- and age-matched 64 healthy controls were obtained from a 3T MRI scanner. Tract-based spatial statistics were used to compare the mean diffusivity of the white matter tract between the groups. Voxel-based analysis was used to compare the mean diffusivity of the subcortical gray matter between the groups. There were white matter deficits in the corticofugal tract, cingulum, uncinate fasciculus, crus of fornix or stria terminalis, corpus callosum, external capsule, superior longitudinal fasciculus, posterior thalamic radiation including optic radiation, and the tracts adjacent to the precuneus and supramarginal gyrus, as indicated by higher mean diffusivity in Parkinsons disease patients than in controls. There were also deficits in the left putamen, pallidum, thalamus, and caudate as indicated by higher mean diffusivity in Parkinsons disease patients than in controls. Using diffusion tensor imaging and multi-methods of image analysis, we successfully characterized and visualized brain white matter and deep gray matter areas with microstructural deficits in Parkinsons disease patients.

Relationship Between 24-Hour Mean Ocular Perfusion Pressure Fluctuation and Rate of Paracentral Visual Field Progression in Normal-Tension Glaucoma

PURPOSE To investigate the relationship between unstable mean ocular perfusion pressure (MOPP) and the rate of paracentral visual field (PVF) progression in patients with medically treated normal-tension glaucoma (NTG). METHODS The data of 157 eyes of 122 patients with NTG who were followed for more than 6 years (mean follow-up, 8.7 years ± 12.6 months) and had more than 5 reliable standard visual field (VF) tests were analyzed retrospectively. Groups in the highest, middle, and lowest tertiles of 24-hour MOPP fluctuation (HMF, MMF, and LMF, respectively) were compared in terms of rates of change of mean thresholds in the central 10° (PVF), 10° to 24°, and global areas by using a linear mixed model. Clinical factors associated with rapid PVF progression were also investigated. RESULTS The LMF and HMF groups did not differ significantly in the mean global rate of VF changes (-0.52 vs. -0.71 dB/y; P = 0.07). The HMF group had a significantly faster progression of VF defects in the central 10° area than the LMF group (-1.02 vs. -0.54 dB/y; P < 0.001) but did not differ in terms of progression of VF defects in the peripheral 10° to 24° area (-0.39 vs. -0.495 dB/y; P = 0.425). PVF progression was significantly associated with 24-hour MOPP fluctuation (β = -0.31, P < 0.001) and VF damage severity at initial presentation (β = 0.134, P = 0.011). CONCLUSIONS Medically treated NTG eyes with greater 24-hour MOPP fluctuations (HMF) had faster PVF defect progression than eyes with stable 24-hour MOPP (LMF). Twenty-four hour MOPP fluctuation associated significantly with PVF progression velocity.

Impact of heart failure with normal ejection fraction on the occurrence of ischaemic stroke in patients with atrial fibrillation

Objectives The purpose of this study is to examine the risk of stroke in patients with heart failure with normal ejection fraction (HFNEF) and atrial fibrillation (AF). Design Clinical and echocardiographic data in patients with non-valvular AF who were not on anticoagulation were retrospectively investigated. A total of 304 patients had AF without heart failure, and 102 patients were diagnosed as AF with HFNEF. Main outcome measures We compared the rate of ischaemic stroke, death and composite of these in the two groups. Results Patients with AF and HFNEF were older than those with AF only (71.6 vs 64.0 years, p<0.001). Female sex, diabetes mellitus, hypertension, chronic kidney disease, angina, myocardial infarction, use of β blocker or digoxin were more common in patients with AF and HFNEF. The rates of ischaemic stroke, death and composite of ischaemic stroke and death were higher in patients with AF and HFNEF than in those with AF only (20.6% vs 6.7%, p<0.001; 27.2% vs 2.0%, p<0.001; 41.2% vs 8.1%, p<0.001 at 3 years for AF with HFNEF vs AF only, respectively). After adjustment with propensity score method using the inverse probability of treatment weighting, the 3-year risks of for ischaemic stroke (HR 3.29; 95% CI 1.58 to 6.86; p=0.001), death (HR 5.52; 95% CI 2.24 to 13.63; p<0.001), and composite of ischaemic stroke and death (HR 4.08; 95% CI 2.30 to 7.26; p<0.001) were significantly higher in patients with AF and HFNEF. Conclusions HFNEF is associated with an increased risk of stroke and death in patients with AF.

Outcomes of laser peripheral iridotomy in angle closure subgroups according to anterior segment optical coherence tomography parameters.

PURPOSE To investigate the effect of laser peripheral iridotomy (LPI) in subgroups of angle closure eyes based on anterior segment optical coherence tomography (AS OCT)-derived parameters. METHODS Angle closure (primary angle closure [PAC] or PAC glaucoma [PACG]) eyes were imaged using AS OCT before and 2 weeks after LPI. A hierarchical cluster analysis was performed using AS OCT parameters obtained before LPI, such as anterior chamber depth (ACD), anterior chamber width (ACW), iris cross-sectional area (IA), angle opening distance and iris thickness at 750 μm from the scleral spur (AOD750, IT750), iris curvature (IC), lens vault (LV), and anterior chamber area (ACA) to subclassify angle closure eyes. After LPI, parameters were compared to evaluate whether the outcome of LPI differed among the subgroups determined by cluster analysis. RESULTS Cluster analysis generated two distinct clusters showing significantly different anatomical features. Cluster 1 (61 eyes) had lower ACD (P<0.001), higher LV (P=0.008), lower AOD750 (P<0.001), and lower ACW (P<0.001) than cluster 2 (27 eyes). The proportional change in AOD750 after LPI was significantly greater in cluster 1 than in cluster 2 (116.4±117.3% and 46.4±45.7%, respectively, P=0.007). CONCLUSIONS The outcomes of LPI differed between angle closure subgroups with different anatomical characteristics. Our results provide evidence that angle closure patients can be grouped according to different anatomical anterior segment features and that the pathogenic mechanism of angle closure may differ among subgroups, suggesting that the treatment and follow-up plan should be customized according to subgroup features.

Investigation of papulopustular eruptions caused by cetuximab treatment shows altered differentiation markers and increases in inflammatory cytokines

Background  Epidermal growth factor receptor (EGFR) critically regulates tumour cell division, survival and metastasis. Agents that inhibit EGFR have been used in the treatment of advanced‐stage malignancies, but cause variable cutaneous side‐effects, most often papulopustular eruptions and xerosis.

Mitral valve repair versus replacement for moderate-to-severe mitral regurgitation in patients undergoing concomitant aortic valve replacement

OBJECTIVES Whether to repair or replace the mitral valve for patients with significant mitral regurgitation undergoing aortic valve replacement is still controversial. METHODS From January 1990 to December 2011, a total of 663 patients underwent aortic valve replacement combined with mitral valve surgery. Among these, 253 patients (mean age 55.9 ± 14.5 years, 91 females) with moderate-to-severe mitral regurgitation were enrolled to compare the outcomes between double valve replacement (DVR group, n = 158) and aortic valve replacement plus mitral valve repair (AVR plus MVr group, n = 95). Survival and valve-related events were compared by the inverse-probability-treatment-weighted method using propensity scores to reduce treatment selection bias. RESULTS Early mortality was similar between the groups (1.9% in the DVR group when compared with 3.2% in the AVR plus MVr group, P = 0.55). During the mean follow-up period of 72.1 ± 56.7 months, 45 patients died (28 in DVR and 17 in AVR plus MVr) and 31 experienced valve-related events including valve reoperation in 11, anticoagulation-related bleeding in 14, thromboembolism complications in 9 and infective endocarditis in 3. After adjustment for baseline risk profiles, the DVR group showed no difference with regard to risks of death (hazard ratio [HR], 1.79; 95% confidence interval [CI], 0.79-4.01; P = 0.16) and valve-related events (HR, 1.15; 95% CI, 0.40-3.30; P = 0.80) compared with the AVR plus MVr group. CONCLUSIONS Although the outcomes of either mitral valve repair or replacement for moderate-to-severe mitral regurgitation in patients undergoing concomitant aortic valve replacement show no statistical significance in terms of long-term survival and valve-related event rates, DVR seems more hazardous than AVR plus MVr based on the estimated HR in terms of survival.

Voice Changes in Elderly Adults: Prevalence and the Effect of Social, Behavioral, and Health Status on Voice Quality

To estimate the prevalence of dysphonia and the effect of several risk factors on vocal quality in a representative population of older adults.

Relationship Between Nocturnal Intraocular Pressure Elevation and Diurnal Intraocular Pressure Level in Normal-Tension Glaucoma Patients.

PURPOSE We studied the relationship between nocturnal habitual position IOP elevation and diurnal IOP level in normal-tension glaucoma (NTG) patients. METHODS A total of 70 young NTG patients with a low diurnal IOP level (mean diurnal seated IOP < 15.0 mm Hg; low IOP group) and 79 age-, axial length-, and disease severity-matched NTG patients with a high diurnal IOP level (mean diurnal seated IOP ≥ 15.0 mm Hg; high IOP group) were recruited prospectively. Intraocular pressure was recorded 11 times over a 24-hour period by a single, well-trained ophthalmology resident using a hand-held tonometer. RESULTS The mean habitual position IOP during nighttime (14.2 mm Hg) was significantly higher than that of daytime (12.8 mm Hg) in the low IOP group (P < 0.001), whereas no such difference was found in the high IOP group (16.4 vs. 16.3 mm Hg, P = 0.706). The low IOP group showed an overall nocturnal acrophase in habitual-position IOP, with 11 patients (15.7%) having a diurnal, 30 (42.8%) a nocturnal, and 29 (41.4%) no evident acrophase. By contrast, the high IOP group showed no evident peak in habitual-position IOP, with 28 patients (35.4%) having a diurnal, 12 (15.2%) a nocturnal, and 39 (49.4%) no evident acrophase. CONCLUSIONS In NTG eyes with a low diurnal IOP, there are significant IOP increases at nighttime in the habitual position, whereas there is no significant nocturnal IOP elevation in NTG eyes with a high diurnal IOP.