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Purpose: To evaluate the relationship between the morphology and retinal function of macular microhole (MMH) variants. Materials and Methods: We evaluated 12 eyes of 11 patients with defects in the IS/OS junction of photoreceptor layer with SD-OCT. All patients underwent comprehensive ophthalmic examination including spectral domain optical coherence tomography (SD-OCT) and microperimetry. Results: The mean logMAR visual acuity in the affected eye was 0.15 ± 0.17 (range 0.00-0.5). Mean horizontal diameter of the MMH was 163 ± 99 μm; the mean retinal sensitivity in the area corresponding to the MMH was 13.79 ± 4.6 dB. Negative correlation was found between the MMH diameter and the retinal sensitivity (r = -0.65, p0 = 0.02). Three morphological patterns of MMH variants were recognized on SD-OCT, which did not differ in retinal sensitivities. Conclusion: We described and classified the MMH variants and made an assessment on the physiological functions using microperimeter.

A 69-year-old lady presented with complaints of decreased vision in left eye since one month. Best Corrected Visual Acuity (BCVA) was 6/18 in that eye. Fundus examination revealed non-central geographic atrophy and soft drusens at macula in both eyes. Temporal periphery of left eye revealed subretinal exudates with altered sub-RPE hemorrhage mimicking peripheral exudative hemorrhagic chorioretinopathy (PEHCR). Fundus Fluorescein Angiogram showed window defects at macula and blocked fluorescence at temporal periphery in left eye. However, Indocyanine green angiography (ICGA) revealed active peripheral choroidal polyps. The patient was successfully treated with intravitreal bevacizumab and ICGA-guided laser photocoagulation. 27 months after laser treatment, BCVA improved to 6/9. Rationale of consecutive anti-vascular endothelial growth factor (VEGF) treatment followed by more definitive laser photocoagulation is that anti-VEGF aids in resolution of subretinal fluid, thus making the polyp more amenable to focal laser photocoagulation which stabilizes the choroidal vasculature and prevents further leakage.

Dear Editor, We read with great interest the authors’ recent report on pre-operative povidone-iodine and ofloxacin instillation in diabetics and non-diabetic patients prior to cataract surgery.[1] The evaluation of antiseptic techniques is particularly important in diabetic patients who may have an increased predisposition to post-operative infection. Evaluating povidone-iodine in diabetic patients is particularly interesting because both can prove to be individually toxic to the cornea. We were interested if the authors did a systematic corneal evaluation as part of their pre-operative and post-operative examination as we did not notice this documented in the study? Diabetes mellitus has been associated with corneal epitheliopathy, decreased corneal oxygen uptake, and altered corneal hysteresis with some evidence suggesting a positive weak correlation with elevated serum glucose levels.[2,3] Povidone-iodine (5%) (PI) has also been associated with toxic corneal epitheliopathy including induction of epithelial cell death and delayed corneal epithelial healing.[4,5] Following pars plana vitrectomy (PPV) for proliferative diabetic retinopathy in poorly controlled diabetics, we have noted a particularly high incidence of peri-operative corneal epitheliopathy. We have speculated that PI and poorly controlled diabetes mellitus may have a synergistic effect in compounding post-operative corneal epitheliopathy. To evaluate this, a retrospective study was conducted of 68 patients who underwent PPV for proliferative diabetic retinopathy. Each patient had thorough pre-operative and post-operative corneal examination, including documentation of fluorescein staining pattern, tear-film breakup time, punctuate epithelial erosions, and epithelial defects. All patients underwent pre-operative preparation with 5% PI to the eyelids, eyelashes, and by flushing the conjunctival fornices with mean contact time of 5 minutes. Fifty percent of eyes developed post-operative corneal epitheliopathy (34 eyes). The average HbA1c for the epitheliopathy group was 8.01% while the average for the non-epitheliopathy group was 8.44%, and this difference was not statistically significant (P = 0.45). There was no statistically significant difference in surgical duration (mean 55 minutes) between patients developing corneal epitheliopathy and not developing corneal epitheliopathy, and there were no cases of endophthalmitis. This study demonstrates a high incidence of corneal epitheliopathy in diabetic patients who underwent PPV for proliferative diabetic retinopathy. There was no correlation between glycosylated hemoglobin levels and corneal epitheliopathy. Further formal studies are warranted to fully investigate this. We would be interested in the authors’ experiences of post-operative corneal evaluation and glycosylated hemoglobin levels from their study, if available.

The association of macular detachment with posttraumatic macular hole is a known but rare occurrence. Spontaneously occurring resolution of the detachment and closure of the macular hole has been reported only once in the literature. We describe a similar rare event in a young male, the documentation of which was done serially by microperimetry (MP) and optical coherence tomography (OCT). A 17-year-old male presented with a decrease in vision following a closed globe injury to the left eye. A coexisting macular hole and macular detachment were detected in the affected eye. Serial follow-up with OCT and MP documented complete resolution of the macular hole and the macular detachment within 1 week of presentation. The case highlights that spontaneous resolution of traumatic macular hole and related macular detachment may occur and a waiting period is advisable before undertaking any corrective surgical procedure. The pathophysiologic mechanisms of causation and the resolution of posttraumatic macular hole-related retinal detachment are discussed.

Sir, I read with interest the article entitled “Assessing Framingham cardiovascular risk scores in subjects with diabetes and their correlation with diabetic retinopathy” by Damkondwar, et al.[1] I want to raise certain issues concerning the validity of the results obtained in the said study. Sir, say, A (Framingham scores in type II diabetics), B [Cardiovascular Disease (CVD) risks in type II diabetics] and C (diabetic retinopathy) are three entities and if one wants to correlate B with C by measuring A, then A and B must have undoubted pre-existing correlation. But in the said study, it was admitted “There is no longitudinal study from India which can suggest whether the scores underestimate or overestimate the CVD risk among subjects with type II diabetes”. It was even not mentioned whether the cross-sectional data obtained in the study were in conformity with the Framingham study or not. Therefore when the standard (Framingham scores) was not standardized (validated) for CVD risks in Indian diabetic population, how can Framingham scores and/or CVD risks be correlated to diabetic retinopathy? Framingham cardiovascular risk score is notoriously known for its high interethnic variability.[2,3] In fact it is often said that Framingham cardiovascular risk score correlates well only in the race from where it is actually evolved. The authors themselves mentioned that in the United Kingdom Prospective Diabetic Study (UKPDS), the Framingham scores underestimated the 10-year risk of CVD in type II diabetics by 32%. Therefore, the said scores though being globally investigated are not globally accepted for application. Hence mentioning Framingham scoring as ‘global risk assessment tool’ and advocating interaction between treating physician/cardiologist and the ophthalmologist on its basis (in the ‘Abstract’ of the said article) is probably not warranted. The results of the study were not compared with other compatible Indian cross-sectional study, in which Framingham scoring was used. Authors’ estimation of 10-year CVD risks in Sankara Nethralaya – Diabetic Retinopathy Epidemiology and Molecular Genetic Study (SN – DREAMS 1) i.e., in the study in question was 33.5%, whereas that estimated by The Indian Atherosclerosis Research Study (IARS) group was only 5.32%.[3] Although the inclusion criteria of the two studies were different (type II diabetes in SN – DREAMS 1 and genetic predisposition in IARS), however, both the criteria were found to have similar CVD risk potentials in the Framingham's cohort and hence tend to be compatible.[4,5] Correlating CVD risks with risks of diabetic retinopathy lacks biological plausibility. While cardiovascular diseases in diabetes are macrovascular in origin, retinopathy is microvascular, and each has distinct and different set of major etiological factors. While cardiovascular diseases are predominantly due to atherosclerosis, retinopathy is predominantly due to glucose dysregulation. That diabetes increases the risk of atherosclerotic diseases by two to three folds is an established fact[5] but the reverse, that is, role of atherosclerotic factors like cholesterol, LDL etc., in the causation of retinopathy is not as clear. Neither any article showing such correlation was cited in the ‘discussion’ section. Therefore, while investigation to this effect is laudable, a hypothetical explanation of this association was expected, and in the absence of explanation, needless to say, the strength of association had been weakened further.

PURPOSE. To evaluate the effect of anterior chamber continuous infusion maintainer system on the contamination of anterior chamber in phacoemulsification surgery. METHODS. Clear corneal phacoemulsification surgery was performed in 132 eyes of 132 randomly selected patients with cataract who were divided into two groups of 66 eyes according to the use of an anterior chamber maintainer (ACM) system. The fluid specimens were taken from anterior chamber in the beginning and at the end of the surgery. They were transferred under anaerobic conditions and investigated by culturing onto blood agar and thiogluconate broth media. Differences between the two groups with respect to contamination of the specimens were investigated. RESULTS. The mean age of the group undergoing surgery without a maintainer system (Group A) was 63 +/- 10 years (min = 41, max = 80) versus 59 +/- 10 years (min = 33, max = 80) in the other group (Group B) in which the maintainer was used during surgery. In the postoperative specimen, Micrococcus species were isolated from one eye (1.5%) in Group A and S. pyogenes in one eye (1.5%) from Group B. Mean follow-up interval was 12 +/- 6 (min = 4, max 28) months. CONCLUSIONS. The use of ACM system in clear corneal phacoemulsification surgery carries no additional risks as far as contamination is concerned.

PURPOSE: To study the nature and frequency of bacterial contamination during cataract surgery. METHODS: The preoperative smears from the conjunctiva and anterior chamber (AC) fluid aspirates during extra-capsular cataract surgery (ECCE) with posterior chamber intraocular lens (PCIOL) implantation in 40 eyes were analysed for aerobic and anaerobic bacteria. Any change in the bacterial strains isolated before and after cataract surgery was also studied. RESULTS: AC fluid aspirates were positive for bacteria in 15 eyes (37.5%). Coagulase-negative Staphylococcus was the most common aerobe (39.4%) and Propionibacterium acnes the most common anaerobe. Of the 15 cases with positive AC fluid cultures, 6 showed an organism in the AC aspirate different from the conjunctival smear. CONCLUSION: Clinically there was no endophthalmitis in any of the eyes. Factors such as preoperative antibiotic use, the antibacterial properties of aqueous, or low inoculum size could explain this. The preoperative conjunctival smear may not be useful in predicting the AC fluid contamination or outcome of cataract surgery

Aim : To compare the bacterial contamination of the anterior chamber (AC) between manual small incision cataract surgery (SICS) and phacoemulsification (Phaco). To study the conjunctival flora and bacterial contamination of AC between well-controlled diabetics and non-diabetics. Materials and Methods : Three hundred and sixty-eight patients were randomized to manual SICS and Phaco. Sixty-eight patients were excluded for not completing follow-up or for intraoperative complications like posterior capsule rupture. One hundred and fifty patients in each group were finally analyzed. Conjunctival swabs were taken on admission, after one day of topical ofloxacin and 15 min after 5% Povidone Iodine (PI) instillation. AC aspirate at the end of the surgery was also cultured. Results : Fifty-six (18.66%) patients had positive conjunctival swab on admission which was reduced to 19 (6.33%) with topical ofloxacin and to five (1.66%) with instillation of 5% PI. AC contamination in both manual SICS and Phaco was 0.66%. The conjunctival flora in diabetics was similar to non-diabetics. None of the diabetics had AC contamination. Statistical analysis was performed by Chi-Square test (with Yates' correction). Conclusion : Statistically significant reduction in conjunctival flora was achieved with topical ofloxacin and 5% PI instillation and AC contamination in both manual SICS and Phaco was minimal (0.66%). Well-controlled diabetics who underwent cataract surgery in this study had similar conjunctival flora and AC contamination as non-diabetics.

Purpose: To study the efficacy of adding vancomycin in irrigating solutions, in comparison to topical antibiotic given preoperatively for a day, during phacoemulsification, in reducing the anterior chamber (AC) contamination. Settings and Design: This was a prospective, interventional, hospital-based study. Materials and Methods: This was a study involving 400 eyes of 400 paitens, undergoing routine phacoemulsification between January 2004 and June 2006. The patients were non-randomly assigned to two groups: Group 1 included 180 patients, who received topical ciprofloxacin eye-drops (four-hourly) for a day preoperatively and Group 2 included 220 patients, who underwent phacoemulsification with vancomycin (20 µg/ml) in the irrigating solution. Anterior chamber aspirate obtained at the end of the surgery was sent for microbial workup. The number of positive cultures in both the groups was determined. Statistical analysis: This was performed using Chi-square test. Results: Aqueous samples showed microbial growth in 38 (21.1%) out of 180 eyes in Group 1 and in 17 (7.7%) out of 220 eyes in Group 2 ( P = 0.001). Coagulase-negative staphylococcus was the most common organism in both the groups. Aqueous samples from four eyes in group 1 showed multiple organisms, while none of the sample from group 2 showed more than one organism. None of the eyes in either group showed fungal contamination. One patient in Group 1 developed endophthalmitis, and the causative organism was Alcaligenes faecalis. All patients were followed up for a minimum of six months (range: 6 to 14 months and mean: 9.3 months). Conclusion: Addition of vancomycin in irrigating solutions is more efficacious in reducing AC contamination in comparison to topical antibiotic administered a day preoperatively.