Clinical study to evaluate the influence of incision site (superior vs superotemporal) on postoperative astigmatism in manual small incision cataract surgery.

Introduction: Small incision cataract surgeries may be performed using various surgical incisions, namely, superior, supero-temporal and temporal. Each method has its own advantages and disadvantages. Supero-temporal incision is considered the best as it produces least induced astigmatism. The purpose of this study was to compare the postoperative induced astigmatism in superior and superotemporal incision group in small incision cataract surgery. Material &Method- This study was conducted on cataract surgery patients admitted in M.R.A Medical College, Ambedkarnagar. Fifty patients were selected for study, out of which 30 received superior and 20 received superotemporal incision. Preoperative keratometric and post operative 6 weeks keratometric readings were analysed. Results-Superior incision is better for with the rule astigmatism and worst for against the rule astigmatism, while superotemporal incision is equally good for both with the rule and against the rule astigmatism. Conclusion-Superotemporal incision is better than superior as it produces least astigmatism with good visual acquity.

Visual evoked responses in ethambutol induced optic neuritis.

Pattern evoked responses were recorded in 46 patients of tuberculosis on ethambutol and 16 healthy subjects. Deterioration in visual acuity was documented in two patients (4.3%). P100 latency was delayed in 16 cases (34.8%), while in 12 patients (26.1%) both latency and amplitude were affected. A cut off latency value of > or = 140 ms was associated with ophthalmological findings. The incidence of subclinical toxicity as detected by visual evoked response (VER) was higher in older subjects, patients on higher doses of ethambutol (> or = 20 mg/kg/day) and longer duration of treatment. Of two cases with objective ocular signs, one who reported for follow up after two months had recovered completely after stopping ethambutol. Recording of VER is an extremely useful objective test for subclinical optic nerve damage.

Ideal number of incisions in radial keratotomy--an experimental study.

The operation is very simple and safe and best for simple myopia. 16 ideal incisions give higher correction. Uniformity in depth of incision and steroid drops used post operatively brings higher correction.