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Lee H.,Institute of Vision Research | Chung J.L.,Yonsei University | Kim E.K.,Institute of Vision Research | Kim E.K.,Konyang University | And 3 more authors.
Journal of Cataract and Refractive Surgery | Year: 2012

Purpose: To compare the corneal astigmatism measurements from 6 instruments in preoperative assessment for toric intraocular lens (IOL) implantation. Setting: Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Seoul, South Korea. Design: Prospective comparative observational study. Methods: This study included patients with cataract and more than 1.00 diopter (D) of corneal astigmatism. For preoperative evaluation of toric IOL implantation, the net astigmatism was evaluated using manual keratometry, autokeratometry, partial coherence interferometry (PCI) (IOLMaster), corneal topography/ray-tracing aberrometry (iTrace), scanning-slit topography (Orbscan), and Scheimpflug imaging (Pentacam). All net astigmatisms were converted to polar values. Using the astigmatism measurements from manual keratometry as a standard, Bland-Altman analysis, linear mixed-model, and bivariate graphic analysis were performed. Results: The study group comprised 257 eyes of 141 patients. Bland-Altman plots showed good agreement between manual keratometry and each instrument for polar values. There was no significant between-instrument difference in KP(90) and KP(135) in the linear mixed model analysis or in bivariate polar values in bivariate confidence ellipses. Conclusion: The corneal astigmatism measurements from autokeratometry, PCI, corneal topography/ray-tracing aberrometry, scanning-slit topography, and Scheimpflug imaging were comparable to those from manual keratometry and can be used interchangeably with manual keratometry to measure corneal astigmatism. Financial Disclosure: No author has a financial or proprietary interest in any material or method Mentioned © 2012 2012 ASCRS and ESCRS. Source


Lee J.E.,Yonsei University | Cho K.H.,Yonsei University | Song S.K.,Korea University | Kim H.J.,Yonsei University | And 4 more authors.
Journal of Neurology, Neurosurgery and Psychiatry | Year: 2014

Background Parkinson's disease with mild cognitive impairment (PD-MCI) is a heterogeneous entity in terms of cognitive profiles and conversion to dementia. However, the risk factors for ongoing cognitive decline in patients with PD-MCI are not clearly defined. Methods 51 patients with PD-MCI were prospectively followed-up for a minimum of 2 years. Subjects were classified as MCI converters (n=15) or MCI nonconverters (n=36) based on whether they were subsequently diagnosed with PD dementia. We explored cognitive profiles and neuroanatomical characteristics of PD-MCI converters using voxel based morphometry (VBM) of grey matter (GM) density and region of interest based volumetric analysis of the substantia innominata (SI). Results PD-MCI converters showed more severe cognitive deficits in frontal executive functions, immediate verbal memory and visual recognition memory compared with PD-MCI non-converters. VBM analysis revealed that PD-MCI converters had significantly lower GM density in the left prefrontal areas, left insular cortex and bilateral caudate nucleus compared with that in PD-MCI nonconverters. The mean normalised SI volume was significantly smaller in both PD-MCI converters (1.19±0.35, p<0.001) and PD-MCI non-converters (1.52±0.27, p<0.001) compared with that in controls (1.87±0.19). PD-MCI converters had a significantly smaller normalised SI volume than PD-MCI nonconverters (p<0.001). Conclusions Our data show that atrophy in the frontostriatal areas and cholinergic structures, as well as frontal lobe associated cognitive performance, may act as predictors of dementia in PD-MCI patients, suggesting distinctive patterns of cognitive profiles and a neuroanatomical basis for progressive PD-MCI. Source


Lee J.E.,Yonsei University | Cho K.H.,Yonsei University | Ham J.H.,Yonsei University | Song S.K.,Korea University | And 3 more authors.
Parkinsonism and Related Disorders | Year: 2014

Objective: To explore whether olfactory performance acts as a cognitive reserve in non-demented patients with Parkinson's disease (PD). Methods: Patients with non-demented PD (n=119) underwent T1-weighted MRI and olfactory identification tests. According to their olfactory performance, PD patients were subdivided into three groups of high score (PD-H, n=38), middle score (PD-M, n=48), and low score (PD-L, n=33). We investigated the pattern of gray matter (GM) density according to olfactory performance using voxel-based morphometry (VBM) and analyzed the correlation between GM density and olfactory performance. Results: No significant differences in demographic characteristics were observed among the groups. A neuropsychological test showed that cognitive deficits in verbal memory function were more severe in the PD-L group than in the PD-H group. However, a VBM analysis revealed that patients in the PD-H group possessed significantly decreased GM density in the bilateral temporal areas, orbitofrontal areas, mesiofrontal areas extending into the cingulate gyrus, and prefrontal areas, compared with patients in the PD-L group. No areas exhibiting a significant difference in GM density were observed between the PD-H and PD-M groups. Olfactory performance in patients with PD was negatively correlated with both the brain GM volume and intracerebral volume; in particular, GM density in the caudate nucleus and putamen exhibited a negative correlation with olfactory performance. Conclusions: Our data show that a high olfactory performance may compensate GM volume loss in order to minimize the exhibition of cognitive impairment and thus may act as a cognitive reserve in non-demented patients with PD. © 2013 Elsevier Ltd. Source


Shin J.,Yonsei University | Choi S.,Yonsei University | Lee J.E.,Yonsei University | Lee H.S.,Yonsei University | And 3 more authors.
Journal of Neurology, Neurosurgery and Psychiatry | Year: 2012

Background: White matter hyperintensities (WMH) in the cholinergic pathways show a stronger correlation with cognitive performance than general WMH in Alzheimer's disease. However, the role of WMH within the cholinergic pathways in cognitive dysfunction has not been investigated in Parkinson's disease (PD). Method: The severity of WMH within the cholinergic pathways of PD subgroups with intact cognition (PD-IC, n=44), mild cognitive impairment (PD-MCI, n=87) and dementia (PDD, n=40) were compared using the Cholinergic Pathways Hyperintensities Scale (CHIPS), and the correlation between the CHIPS score and performance on individual tests of cognitive subdomains were analysed. Results The mean CHIPS score was significantly higher in patients with PDD compared with those with PD-IC (p=0.03) or PD-MCI (p=0.015). The CHIPS score in patients with PD was negatively correlated with general cognition assessed using the Mini-Mental State Examination (r=-0.28, p<0.001) and positively with the Unified Parkinson's Disease Rating Scale motor score (r=0.24, p=0.002). The CHIPS score showed a significant correlation with cognitive performance on individual cognitive subdomains and had the highest independent correlations with contrasting programme (β=-0.33, p<0.001) and forward digit span (β=-0.17, p=0.04). Conclusions: This study demonstrated that the burden of WMH within cholinergic pathways was significantly higher in patients with PDD relative to other groups, and that cholinergic WMH was significantly correlated with a decline in frontal executive function and attention. Source


Shin S.,Yonsei University | Lee J.E.,Yonsei University | Hong J.Y.,Yonsei University | Sunwoo M.-K.,Yonsei University | And 3 more authors.
Journal of Neurology, Neurosurgery and Psychiatry | Year: 2012

Background: Visual hallucinations (VH), which are common in patients with Parkinson's disease (PD), lead to increased disability and are a significant predictor of the development of dementia. However, the neuroanatomical basis for VH in non-demented PD patients remains controversial. Methods: A total of 110 patients with PD were classified into PD with VH (n=46) and PD without VH (n=64) groups, depending on the presence of VH assessed by the caregiver-based structured interview of the Neuropsychiatric Inventory. We performed voxel-based morphometry (VBM) for grey matter (GM) volume and a region-of-interest-based volumetric analysis of the substantia innominata (SI) between two groups. Results: The comprehensive neuropsychological assessment showed that PD patients with VH showed more severe cognitive deficits in delayed visual memory and frontal executive functions compared with those without VH. A VBM analysis revealed that PD patients with VH had significantly lower GM volume in the right orbitofrontal, left temporal and left thalamic areas compared with those without VH. The normalised SI volume was significantly reduced in PD patients with VH compared with those without VH (1.28±0.22 vs 1.41±0.25, p=0.005). Conclusions: The present study demonstrates that non-demented PD patients with VH exhibited a smaller volume in the frontal, temporal and thalamic areas as well as the SI, suggesting that PD hallucinators may have distinctive neuroanatomical bases relative to PD non-hallucinators. Source

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