Monday, December 31, 2012

THE EFFECT OF SMOKING ON PUPIL SIZE AND PHOTOSTRESS RECOVERY

This study published in Ophthalmic Research aimed to determine the effect of chronic smoking on the pupil and photostress recovery time. 

40 heavy smokers and 40 age- and sex-matched nonsmokers had full vision and no ocular problems. Photostress recovery times were similar in smokers and nonsmokers. Scotopic pupil sizes in smokers were similar; however, photopic pupil size in smokers was different from nonsmokers. 

Conclusions: Chronic smoking may dilate the pupil, and increases macular foveal threshold value immediately after photostress.

Monday, December 17, 2012

ACUTE ANGLE CLOSURE CAN OCCUR EVEN POST PERIPHERAL IRIDOTOMY

This case study published in Biomedical Central Ophthalmology describes the following case:


A 56-year old Chinese female was diagnosed of primary angle closure glaucoma and had bilateral laser peripheral iridotomy one year ago. She presented with spontaneous onset of malignant glaucoma involving the left eye. The condition was treated successfully; the final best corrected visual acuity was 0.67 (decimal notation).
This case highlights that acute angle closure attack can occur in an eye with patent peripheral iridotomy. Early recognition and treatment is essential for good visual prognosis.

USING STEROIDS IN BACTERIAL CORNEAL ULCERS

This study in Ophthalmic Epidemiology concludes that the adjunctive use of topical steroids in bacterial corneal ulcers improves visual outcome.  Personally I wait until the ulcer is mostly healed before considering the use of topical steroids to minimize scarring.

Tuesday, December 04, 2012

MICROANEURYSM TURNOVER ASSOCIATED WITH INCREASE RISK OF DIABETIC CLINICALLY SIGNIFICANT MACULAR EDEMA

This was a study published in Diabetes Care.  Turnover rate is defined as the rate at which macular microaneurysms appear and then disappear.  This is justification for photographing carefully diabetics with any microaneurysms.

The study concluded:

microaneurysm (MA) turnover predicts development of clinically significant macular edema( CSME) in eyes with non proliferative diabetic retinopathy. Low MA turnover values identify well the eyes that are less likely to develop CSME in a 2-year period.


CORNEAL CROSS-LINKING SAFE AND EFFECTIVE IN CHILDREN. BUT...

This study published in the Journal of Refractive Surgery asked the question if corneal cross linking (CXL) is safe and effective in children newly diagnosed with keratoconus.  The study concluded that the procedure is effective,...:


...However, significant maximal keratometry reduction observed up to 24 months after corneal cross-linking lost significance at 36 months.
CONCLUSIONS:
Cross-linking seems to be safe in children and adolescents. We propose that awaiting documentation of progression is not mandatory and corneal cross-linking in children and adolescents should be performed as soon as the diagnosis has been made. However, the effect of arrest of disease progression might not be as long-lasting as in adults and longer follow-up is needed to verify this trend.

Monday, December 03, 2012

COLLAGEN CROSS-LINKING FOR KERATOCONUS

Below is the abstract for the study published in Clinical & Experimental Ophthalmology:


Results

Analysis of the treated group demonstrated a significant flattening of maximum keratometry by 0.96 + 2.33 D (p = 0.005) and a significant improvement in visual acuity by 0.05 + 0.13 logMAR (p = 0.04). In the control group, maximum keratometry increased significantly by 0.43 +0.85 D (p = 0.05) and visual acuity decreased by mean 0.05 + 0.14 (p = 0.2). No statistical differences were noted regarding cylindrical power, spherical equivalent or corneal thickness in both groups.

Conclusions

Results indicate that corneal collagen crosslinking using riboflavin and ultraviolet-A is effective as a therapeutic option in cases of progressive keratoconus by reducing the corneal curvature and improving the visual acuity in these patients.