Garudadri Chandrasekhar

The LOXL1 Gene Variations Are Not Associated with Primary Open-Angle and Primary Angle-Closure Glaucomas

PURPOSE Glaucoma is a complex disease involving multiple genetic factors. Recently, single nucleotide polymorphisms (SNPs) in the LOXL1 gene have been implicated in exfoliation syndrome (XFS) and exfoliation glaucoma (XFG) but not in the primary glaucomas. This study was conducted to determine the possible involvement of these SNPs in cases of primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG). METHODS The three associated SNPs of LOXL1 (rs1048661, rs3825942, and rs2165241) were screened in 208 unrelated and clinically well-characterized glaucoma cases comprising patients with POAG (n = 112) or PACG (n = 96) along with 105 ethnically matched normal control subjects from Indian populations. Subjects with exfoliative material on the lens and radial pigmentation in the periphery of the lens that could be earlier signs of XFS were excluded. These SNPs were screened by resequencing and further confirmed by PCR-based restriction digestions. Haplotypes were generated with the three SNPs in cases and control subjects, and linkage disequilibrium (LD) and haplotype analysis were performed with the Haploview software, which uses the EM (expectation-maximization) algorithm. RESULTS The SNPs of LOXL1 did not exhibit any significant association with POAG or PACG, unlike previous studies from Icelandic, Swedish, U.S., and Australian populations with XFS/XFG. Haplotypes generated with these intragenic SNPs did not indicate any significant risk with POAG or PACG phenotypes. The risk haplotype G-G in XFS/XFG in other populations was present in 46% of the normal control subjects in the present cohort. CONCLUSIONS The results from the present study do not indicate the involvement of the LOXL1 SNPs in POAG and PACG.

Applying the recent clinical trials on primary open angle glaucoma: the developing world perspective.

Abstract:Recent clinical trials have provided scientific guidelines for the treatment of ocular hypertension and primary open angle glaucoma. The developing world need to apply these trials in a sensible and cost effective manner. The number needed to treat (NNT) attempts to tailor treatment to the individual patient. The NNT for the average ocular hypertensive is 20. Those with intraocular pressure ≥26 mm Hg have an NNT of 6. Restricting treatment to those with lower central corneal thickness and or high cup disc ratios can further lower NNT and make treatment more cost effective. The NNT for the average patient with early POAG is 5. Targeting those at higher risk for progression, (bilateral POAG, higher IOP and or pseudo-exfoliation) can further reduce NNT. As far as the modality of treatment is concerned, provided quality can be ensured, collaborative initial glaucoma treatment study (CIGTS) could be interpreted to justify primary surgery in the developing world context.Population attributable risk percentage (PAR), a measure that reflects the public health importance of a disease was used to extrapolate results to the overall population. Ocular hypertension has an “effective” PAR of 8.5%, a value not considered high enough to warrant public health intervention. POAG had an “effective” PAR of 16%, perhaps high enough to be considered a public health problem and justify inclusion as a target disease in the Vision 2020 program. However the logistics and opportunity costs of diagnosis and treatment would probably prevent inclusion of POAG in public health budgets of most developing countries.

Port-wine vascular malformations and glaucoma risk in Sturge-Weber syndrome

highlight a controver-sial yet important issue. Based on the biologically plausibleassumption that glaucoma might worsen after laser therapyto port-wine stain (PWS), this study looked at data to con-firm or negate this hypothesis. However, the answer seemsinconclusive and counterintuitive.Contrary to previous belief, the authors concluded thatthe incidence of glaucoma did not increase with laser treat-ment compared to no laser treatment for PWS.

Recurrent uveitis and pigment dispersion in an eye with in-the-bag acrylic foldable intraocular lens

Phacoemulsification with in-the-bag intraocular lens (IOL) implantation is the standard procedure for cataract surgery. Pigment dispersion and uveitis can result when an IOL is placed in the sulcus. We report a case of a 64-year-old woman, with pigmentary glaucoma, who developed recurrent uveitis following uneventful cataract surgery and an in-the-bag hydrophobic acrylic IOL implant. Recurrent uveitis did not subside despite use of topical steroids over 3 months. Dilated examination revealed capsulophimosis with anterior dislocation of the IOL haptic. The mechanical trauma to the iris due to the displaced haptic was implicated as the cause of recurrent uveitis, which completely resolved after capsular excision and IOL repositioning. This case illustrates a rare cause of recurrent uveitis due to IOL haptic dislocation following severe capsulophimosis.