Background: The aim of this study was to compare how diabetic retinopathy was detected from red-free digital images and colour transparencies. Methods: Two o phthalmologists graded two-field, nonster eoscopic, 60°...Background: The aim of this study was to compare how diabetic retinopathy was detected from red-free digital images and colour transparencies. Methods: Two o phthalmologists graded two-field, nonster eoscopic, 60°red-free digital image s and colour transparencies utilizing an ETDRS-based grading scale, from 107 ma inly type 2 diabetic patients. The discordantly scored eyes were graded by the g raders together to obtain a consensus level of retinopathy for each method. The eyes with discordant consensus grading results were further graded using all ava ilable photographic material to reach a final consensus level of diabetic retino pathy. Intermethod variations were presented as percentages and using kappa (k) and weighted kappa (wk) statistics. The errors of the two consensus gradings wit h respect to the final consensus grading were compared using McNemar’s test. Re sults: For the colour transparencies there was an agreement between the individu al and the consensus grading results in 93%(k=0.90, wk=0.97) and 86%(k=0.79, w k 0.88) for grader 1 and grader 2. Corresponding figures for red-free digital i mages were 88%(k=0.83, wk=0.96) and 84%(k=0.78, wk 0.91). Agreement between me thods was obtained in 76/107 eyes (71%; k=0.58 and wk=0.79). In the 31 discorda ntly graded eyes the level of retinopathy was underestimated in 20/31 (64%) vs 7/31 eyes (23%) and overestimated in 1/31 (3%) vs 3/31 eyes (10%) from colour transparencies and red-free digital images, respectively. The error tendencies were significantly lower when using red-free digital images (p < 0.008). Concl usions: Red-free digital images are comparable with two-field colour transpare ncies in the identification of mild to moderate nonproliferative diabetic retino pathy.展开更多
Background and Purpose Cerebral autosomal dominant arteriopathy with subcort ical infarcts and leukoencephalopathy (CADASIL) is a progressive systemic nonath erosclerotic angiopathy which causes ischemic strokes and v...Background and Purpose Cerebral autosomal dominant arteriopathy with subcort ical infarcts and leukoencephalopathy (CADASIL) is a progressive systemic nonath erosclerotic angiopathy which causes ischemic strokes and vascular subcortical d ementia. A cross sectional study was performed to examine the retinal vascular caliber and blood flow in CADASIL. Methods Scanning laser Doppler flowmetry wa s used in a case control study (11 patients and controls) of peripapillary reti nal circulation. Automated full field perfusion image analysis was used to anal yze the flow data. Retinal vessel calibers were measured from retinal images acq uired with scanning laser ophthalmoscopy. The caliber of the superior and inferi or temporal retinal artery and vein were measured 1 and 2 mm from the disc rim, and the mean values were used for analysis. Results Retinal capillary peak sys tolic flow (mean, 249 versus 311 arbitrary unit [AU]; P=0.072) was lower, and mean capillary flow (mean, 184 versus 224 AU; P= 0.12) and minimum diastolic flow (mean, 105 versus 132 AU; P=0.16) tended to be lower in patients than in controls. No significant difference in the calibers of proximal retinal arteries (mean, 104 versus108 μm) and veins (mean, 150 versus 145 μm) was found between the patients and controls. Conclusions -Retinal cap illary blood flow is mild to moderately reduced in CADASIL but that does not app ear to cause major ischemic injury. Such reduction is analogous to that in the c erebral cortex in CADASIL patients with which retina appears to share its relati ve sparing from severe arterial ischemic tissue damage.展开更多
文摘Background: The aim of this study was to compare how diabetic retinopathy was detected from red-free digital images and colour transparencies. Methods: Two o phthalmologists graded two-field, nonster eoscopic, 60°red-free digital image s and colour transparencies utilizing an ETDRS-based grading scale, from 107 ma inly type 2 diabetic patients. The discordantly scored eyes were graded by the g raders together to obtain a consensus level of retinopathy for each method. The eyes with discordant consensus grading results were further graded using all ava ilable photographic material to reach a final consensus level of diabetic retino pathy. Intermethod variations were presented as percentages and using kappa (k) and weighted kappa (wk) statistics. The errors of the two consensus gradings wit h respect to the final consensus grading were compared using McNemar’s test. Re sults: For the colour transparencies there was an agreement between the individu al and the consensus grading results in 93%(k=0.90, wk=0.97) and 86%(k=0.79, w k 0.88) for grader 1 and grader 2. Corresponding figures for red-free digital i mages were 88%(k=0.83, wk=0.96) and 84%(k=0.78, wk 0.91). Agreement between me thods was obtained in 76/107 eyes (71%; k=0.58 and wk=0.79). In the 31 discorda ntly graded eyes the level of retinopathy was underestimated in 20/31 (64%) vs 7/31 eyes (23%) and overestimated in 1/31 (3%) vs 3/31 eyes (10%) from colour transparencies and red-free digital images, respectively. The error tendencies were significantly lower when using red-free digital images (p < 0.008). Concl usions: Red-free digital images are comparable with two-field colour transpare ncies in the identification of mild to moderate nonproliferative diabetic retino pathy.
文摘Background and Purpose Cerebral autosomal dominant arteriopathy with subcort ical infarcts and leukoencephalopathy (CADASIL) is a progressive systemic nonath erosclerotic angiopathy which causes ischemic strokes and vascular subcortical d ementia. A cross sectional study was performed to examine the retinal vascular caliber and blood flow in CADASIL. Methods Scanning laser Doppler flowmetry wa s used in a case control study (11 patients and controls) of peripapillary reti nal circulation. Automated full field perfusion image analysis was used to anal yze the flow data. Retinal vessel calibers were measured from retinal images acq uired with scanning laser ophthalmoscopy. The caliber of the superior and inferi or temporal retinal artery and vein were measured 1 and 2 mm from the disc rim, and the mean values were used for analysis. Results Retinal capillary peak sys tolic flow (mean, 249 versus 311 arbitrary unit [AU]; P=0.072) was lower, and mean capillary flow (mean, 184 versus 224 AU; P= 0.12) and minimum diastolic flow (mean, 105 versus 132 AU; P=0.16) tended to be lower in patients than in controls. No significant difference in the calibers of proximal retinal arteries (mean, 104 versus108 μm) and veins (mean, 150 versus 145 μm) was found between the patients and controls. Conclusions -Retinal cap illary blood flow is mild to moderately reduced in CADASIL but that does not app ear to cause major ischemic injury. Such reduction is analogous to that in the c erebral cortex in CADASIL patients with which retina appears to share its relati ve sparing from severe arterial ischemic tissue damage.
