Comparison of the safety and efficacy of Mitomycin C 0.02% used intra-operatively by subconjunctival injection versus direct scleral application using sponges in phacotrabeculectomy: A prospective randomized controlled trial.

PURPOSE: To compare the safety and efficacy of subconjunctival injection (MMC: 0.02%) to those with subconjunctival application of sponges soaked in Mitomycin C (MMC: 0.02%) intra-operatively in patients who underwent phacotrabeculectomy. METHODS: A total of 68 patients undergoing phacotrabeculectomy were randomized into two groups; the sponge group received 0.02% MMC-soaked sponges (n = 38), and the injection group received subconjunctival injection of 0.02% MMC (n = 30). The primary outcome was post-operative mean intra-ocular pressure reduction (IOP). The secondary outcomes were bleb morphology using Indiana Bleb Appearance Grading Score (IBAGS) and anterior segment optical coherence tomography (AS-OCT), post-operative use of 5-fluorouracil, and complications rates. These were compared at 1 week and 1, 3, and 6 months post-operatively. Complete success was defined as ≥30% reduction in IOP without anti-glaucoma medications. RESULTS: In sponge and injection groups, the mean pre-operative IOP was 29.1 ± 8.1 and 29.8 ± 8.8 mmHg, respectively. At 6 months, IOP in sponge and injection groups reduced by 52% (14 ± 3.6 mmHg, P < 0.001) and 50% (15.2 ± 4.1 mmHg, P < 0.001), respectively. Complete success was observed in 90.9% in the sponge group and 95.83% in the injection group. Both groups had diffuse, shallow, relatively avascular blebs at 6 months using IBAGS and AS-OCT. A few complications were seen in the sponge group during this period, which were not vision-threatening. CONCLUSION: Subconjunctival MMC injection is an effective, safe, convenient, and time-saving alternative to sponge-soaked delivery of MMC in phacotrabeculectomy.

Does the ISNT Rule Apply to the Retinal Nerve Fiber Layer?

PURPOSE: To determine whether the ISNT rule (Inferior>Superior>Nasal>Temporal) or the "IST" rule (Inferior>Superior>Temporal) can be applied to the peripapillary retinal nerve fiber layer (RNFL) thickness as measured using Heidelberg Retinal Tomography (HRT) and Optical Coherence Tomography (OCT). MATERIALS AND METHODS: This was a cross-sectional study of 189 normal and 42 glaucomatous eyes. RNFL thicknesses measured in different quadrants using HRT and OCT were compared to determine the percentage of eyes obeying the ISNT and IST rule. RESULTS: The HRT-measured mean RNFL thickness in normal eyes showed that 25.9% obeyed the ISNT rule and 70.4% conformed to the "IST" rule. The "IST" rule was able to identify normal eyes better (P=0.040), but had a poor sensitivity (45%) and specificity (70%) to diagnose glaucoma. The OCT-measured average RNFL thickness showed that 47.1% of normal eyes obeyed the ISNT rule and 58.7% conformed to the "IST" rule. Exclusion of the nasal sector also increased the number of glaucomatous eyes conforming to the IST rule (31% obeyed the ISNT rule and 50% obeyed the IST rule). Sensitivities and specificities of the ISNT and the IST rules for OCT-quantified RNFL ranged from 42% to 77%. CONCLUSIONS: A larger number of normal eyes obeyed the IST rule compared with the ISNT rule for the RNFL thickness measured by HRT and OCT. Exclusion of the nasal sector from the analysis (IST rule) marginally improved the specificity in diagnosing glaucoma at the cost of the sensitivity, making neither of these parameters (ISNT and IST) likely to be useful clinically.

Corneal thickness and intraocular pressure in a nonglaucomatous Burmese population: the Meiktila Eye Study.

OBJECTIVE: To determine correlates of central corneal thickness (CCT) and its relationship to intraocular pressure (IOP) in a Burmese population. METHODS: We performed a population-based survey of inhabitants 40 years or older in Myanmar; of 2076 participants, data from 1909 nonglaucomatous subjects who underwent ultrasound pachymetry and Goldmann applanation tonometry were analyzed. Linear mixed effects models adjusting for nonindependence of right and left eye data were constructed. RESULTS: Mean (SD) CCT was 521.9 (33.3) microm, and the mean (SD) IOP was 14.5 (3.4) mm Hg. Intraocular pressure and spherical equivalent were significant predictors of CCT (P < .001 and P = .01, respectively). Age, sex, body mass index, and corneal curvature were not significant predictors. Central corneal thickness was the only significant predictor of IOP (ie, an increase of 100 microm in CCT predicted an increase of 1.3 mm Hg in IOP). The Spearman correlation between CCT and IOP for the right and left eyes was highly significant (P < .001), but the Spearman rank correlation values (R(2) = 0.016 and R(2) = 0.017, respectively) were weak. CONCLUSIONS: The CCT in this Burmese population was significantly associated with IOP and spherical equivalent. The weak association between CCT and IOP is consistent with that of other population-based studies. Other corneal factors are likely to influence Goldmann applanation tonometry.

The clinical applications of fluorouracil in ophthalmic practice.

Fluorouracil (5-fluorouracil, 5-FU) is a pyrimidine analogue that was originally known for its widespread use as an anticancer drug. The ability of 5-FU to reduce fibroblastic proliferation and subsequent scarring has made it an important adjunct in ocular and periorbital surgeries. It is used in primary glaucoma filtering surgeries and in reviving failing filtering blebs, in dacryocystorhinostomy, pterygium surgery, and in vitreoretinal surgery to prevent proliferative vitreoretinopathy. In addition, 5-FU is also gaining recognition in the treatment and surgical management of ocular surface malignancies like ocular surface squamous neoplasia; however, the specific action of the drug on highly proliferating cells limits its use in primary acquired melanosis of the conjunctiva. When applied topically, this drug has a low rate of sight-threatening adverse effects, is inexpensive, and is easy to administer, making it an important tool in enhancing the success rate in ophthalmic surgery and in reducing the recurrence of ocular surface neoplasia.

Mitomycin: clinical applications in ophthalmic practice.

Mitomycin (mitomycin C; MMC) is an antibiotic isolated from Streptomyces caespitosus. The drug is a bioreductive alkylating agent that undergoes metabolic reductive activation, and has various oxygen tension-dependent cytotoxic effects on cells, including the cross-linking of DNA. It is widely used systemically for the treatment of malignancies, and has gained popularity as topical adjunctive therapy in ocular and adnexal surgery over the past 2 decades. In ophthalmic medicine, it is principally used to inhibit the wound healing response and reduce scarring of surgically fashioned ostia. Hence, it has been used as adjunctive therapy in various ocular surgeries, such as glaucoma filtering surgeries, dacryocystorhinostomy, corneal refractive surgery and surgeries for ocular cicatrisation. In addition, it has been used as an adjunct in the surgical management of pterygia, ocular surface squamous neoplasia, primary acquired melanosis with atypia and conjunctival melanoma. In many of these surgeries and ophthalmic pathologies, MMC showed a significant beneficial effect.

Comparison between latanoprost and brimonidine efficacy and safety in Indian eyes.

PURPOSE: To compare the short-term efficacy and safety of topical latanoprost and brimonidine in Indian eyes. MATERIALS AND METHODS: Twenty-eight patients with ocular hypertension, primary open-angle, pseudoexfoliation or pigmentary glaucoma were enrolled. Following baseline measurements, latanoprost was applied topically once daily in the evening for 12-weeks. After a washout period, brimonidine was applied twice daily in all patients for 6 weeks; 16 patients continued for 12 weeks. Patients were examined at 2, 6 and 12 weeks. The primary outcome measure was the difference in mean intra ocular pressure (IOP) reduction at 6 and 12 weeks. The mean diurnal variation of IOP at baseline and at 12 weeks was also compared. RESULTS: Twenty-six of 28 enrolled patients completed the study. One randomly selected eye of each patient was used for analysis. At 6 weeks, the mean IOP reduction was 11.2 mm Hg (+/- 2.9 mmHg) with latanoprost and 6 mmHg (+/- 3.3 mmHg) with brimonidine. At 12 weeks this was 10.8 mmHg (+/- 2.8 mmHg) and 6.9 mmHg (+/- 3.1 mmHg) respectively. At 6 weeks 85.7% (24) eyes obtained more than 25% reduction in IOP with latanoprost compared to 13 (46.4%) with brimonidine. IOP reduction was maintained with both drugs throughout the study period. Two eyes did not show any response to brimonidine. Latanoprost reduced the diurnal variation of IOP from 5.10 to 2.90 mmHg; brimonidine reduced it from 4.70 to 3.90 mmHg. Conjunctival hyperaemia was present in one patient on latanoprost and three patients on brimonidine. Two patients experienced drowsiness with brimonidine. Neither drug produced side effects necessitating withdrawal from the study. CONCLUSION: In this short-term study, both latanoprost and brimonidine effectively reduced IOP and stabilised the diurnal curve in Indian eyes. Latanoprost was more effective than brimonidine.