Autofluorescence imaging of pingueculae.

AIMS: To analyse the autofluoresence (AF) properties of pingueculae and compare the size of AF with the extent of the visible lesion. METHODS: Forty eyes of 23 patients with pingueculae were included in the study. AF images were obtained using an HRA2 confocal scanning laser ophthalmoscope; anterior segment photographies were obtained using TRC-50IX, IMAGEnet 2000 Digital Imaging System. The AF characteristics of pingueculae were analysed. The extent of visible lesion in anterior segment photography and AF image was compared. RESULTS: AF images revealed well-defined hyper-autofluorescence in the area of pinguecula, which was greater than the extent of visible pinguecula in the slit-lamp examination, in 40 of 56 lesions (71.4%). In none of the eyes was the hyperautofluorescent area smaller than the extent of visible lesion. CONCLUSION: Pingueculae display hyperautofluorescence in AF imaging. The real size of pingueculae may be estimated by its AF characteristics, which is mostly larger than the visible lesion.

Optical coherence tomography evaluation of macular edema after intravitreal triamcinolone acetonide in patients with parafoveal telangiectasis.

PURPOSE: Parafoveal telangiectasis (PT) is a developmental or acquired microvascular abnormality of the macula. Leakage of the abnormal parafoveal capillaries leads to macular edema with subsequent decrease in visual acuity. Intravitreal triamcinolone acetonide is recently widely used in the management of intraocular proliferative, edematous, and neovascular diseases. METHODS: This report presents the evaluation of three cases with PT in whom intravitreal triamcinolone acetonide (IVTA) injection was performed. Fundus fluorescein angiography (FA) and optical coherence tomography (OCT) were used in follow-up of the patients. RESULTS: Following pars plana intravitreal injection of 4 mg of triamcinolone acetonide, the patients had angiographic improvement of the macular edema and minimal decrease in retinal thickness on OCT, accompanied by improvement in visual acuity and subjective visual assessment. CONCLUSIONS: The results of the present study on parafoveal capillary telangiectasis suggest that the intravitreal injection of triamcinolone acetonide may be a therapeutic option to increase visual acuity and decrease vascular leakage on FA. Following IVTA procedure, follow-up of these patients with both OCT and FA is important for correct clinical evaluation. Future studies on this method seem to be warranted.

An experimental study on the effect of collagen shields and therapeutic contact lenses on corneal wound healing.

We evaluated the effects of collagen shields and therapeutic contact lenses on corneal wound healing in rabbits. A corneal wound was created by mechanical removal of the central 6-mm zone of the corneal epithelium and basement membrane in 30 eyes of 15 rabbits. The animals were divided into three groups: five rabbits in the first group were treated with a collagen shield in one eye and a therapeutic lens in the other eye. In the remaining two groups, either a collagen shield or a therapeutic lens was applied in one eye and the other eye served as the control. The radius and area of the wound were measured at 0, 6, 24, and 48 h after wounding. Linear regression analysis revealed a significant reduction in the wound area with time in all groups. The healing rate was found to be 0.52 +/- 0.08 mm2/h in the collagen shield, 0.54 +/- 0.05 mm2/h in the therapeutic lens, and 0.43 +/- 0.06 mm2/h in the control group. Comparison of the study groups by Bonferroni modification of analysis of variance revealed no statistically significant difference between the collagen shield and the therapeutic lens group at any time (p > 0.05), whereas a significantly larger wound size was observed in the control group compared with the treatment groups at all times studied (p < 0.05 at 6 h; p < 0.001 at 24 and 48 h). In conclusion, our results indicate that both collagen shields and therapeutic lenses enhance wound healing in rabbit eyes.

Alteration of visual function in impaired glucose tolerance.

People with impaired glucose tolerance are considered to be prone to diabetes. To evaluate their visual function we investigated colour vision with the Farnsworth-Munsell 100 Hue test and contrast sensitivity with Arden's grating cards in people with imparied glucose tolerance (IGT), people with normal glucose tolerance (NGT) and others with type II diabetes (NIDDM). Eyes with low vision or any anterior or posterior segment abnormalities were excluded. Contrast sensitivity and color vision differed significantly between the groups (p < 0.01). It thus appears that patients with IGT but without clinical diabetes could be followed up to see whether these alterations have any predictive value for the development of diabetes and diabetic retinopathy.