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The purpose of this study is to identify factors in the sera of highly sensitized (HS) patients (pts) that inhibit T-cell alloresponses. An in vitro assay was used to measure HLA class I and class II-like antiidiotypic antibodies (anti-ids). The stimulation index (SI) was used to measure PBL and T-cell responses to alloantigens. All HS sera (32 pts) and the IgG fraction inhibited PBL and CD4(+) T-cell responses to alloantigens. The SI with HS IgG was 7.9 +/- 1.7 as compared to 31.5 +/- 5.9 with normal IgG (p = 0.0003). In a subset of pts who were transiently sensitized, the SI was 6.6 +/- 1.0 with a high panel reactive antibody (PRA), but when their PRA was zero, the SI was 17.8 +/- 1.3 (p = 0.0000001). Anti-ids were found in 100% of 17 pts with a high PRA. The T-cell inhibitory factors reduced CD4(+) T-cell responses of HS pts to alloantigens in the presence of autologous anti-ids, were MHC restricted and were inactivated by in vitro generated antibodies to HLA class II-like anti-ids. The HLA class II-like anti-id IgG molecules bind to the TCR of CD4(+) T cells and may impair their ability to help in the downregulating antibody response to anti-ids.

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OBJECTIVES: To evaluate the efficacy of postenucleation saline wash and the effect of different antimicrobial agents on the microbial contamination of donor eyes. METHODS: Two hundred donor eyes were given saline wash and treated with any one of the following 5 randomly selected antimicrobial solutions: 1% povidone-iodine for 3 min, 0.3% gentamycin for 10 min, 0.3% ciprofloxacin for 10 min, a combination of neomycin 1,700 IU, gramicidin 0.025% and polymyxin B 5,000 IU (Neosporin(R)) for 10 min and a combination of 0.3% amikacin for 10 min, followed by 2.5% cefazolin for 10 min. Limbal swabs were sent for culture before and after saline wash and after treatment with antimicrobial agents. RESULTS: On culture of the pretreatment swabs, 77.5% were positive for growth with 75.5% bacterial and 11.5% fungal. Coagulase-negative Staphylococcus (29.1%) was the most common bacterial contamination followed by Pseudomonas aeruginosa (18.5%), Acinetobacter sp. (18.5%) and Alcaligenes faecalis (13.2%). A 20-ml sterile saline wash resulted in a 20% decrease (p < 0.01) in the amount of contamination. The maximum antimicrobial effect with regard to bacterial decontamination was achieved with povidone-iodine (64% decrease in the amount of contamination, p < 0.01) followed by ciprofloxacin (47.6% decrease, p < 0.05), the combination of cefazolin and amikacin (42.5%, p < 0.05), Neosporin (38.5%, p < 0.05) and then gentamycin (21.7%, p = NS). CONCLUSIONS: A thorough saline wash and treatment with 1% povidone-iodine for 3 min is a more effective method for the decontamination of donor eyes as compared to most currently available and frequently used antibiotics.

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PURPOSE: To assess the efficacy of newer surgical technique of sclerokeratoplasty in cases of refractory corneal ulcers of the cornea and to compare it with therapeutic penetrating keratoplasty. METHODS: A randomized, prospective clinical trial in 20 eyes with refractory corneal ulcers was undertaken. Ten eyes each underwent sclerokeratoplasty (group I) or therapeutic penetrating keratoplasty (group II). Infections were considered cured if there was no evidence of corneal infiltration for 1 month following keratoplasty. Postoperative complications, visual acuity (VA), keratometry and graft status were evaluated with both the procedures after a minimum follow up of 1 year. RESULTS: Postoperative complications included epithelial defects, shallow anterior chamber, uveitis and secondary glaucoma, which were present following both procedures, with no significant difference in the frequency of complications between the two techniques (P < 005), Graft clarity and VA with both procedures were comparable. Significantly reduced astigmatism of < 1 D was seen in six eyes in group II in comparison with group I, where astigmatism of > 1.5 D was present in six eyes. Two eyes in group II developed re-infection, of which one was re-operated on, and the other developed endophthalmitis. CONCLUSIONS: Sclerokeratoplasty is a useful alternative to therapeutic penetrating keratoplasty in cases of refractory corneal ulcers with optimum clinical and useful visual outcome.

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PURPOSE: To find out the role of Catalin in the prevention of posterior capsular opacification (PCO), we undertook this experimental study in rabbits. METHODS: Twenty rabbits (10 for the Catalin group and 10 for the placebo group) were operated on for extracapsular clear lens extraction in an aseptic environment. In all cases, capsulorrhexis of 8 mm diameter was carried out. Both the test drug and placebo were given at a dose of 4 times/day from the first postoperative day for 8 weeks. Common drugs in both groups were topical corticosteroid, antibiotic and cycloplegic drops. Periodic slitlamp examinations and photographic documentations were carried out to find any evidence of aftercataract. At the end ot 8 weeks, histopathological examination was carried out to document any evidence of aftercataract. RESULT: Overall, evidence of aftercataract was seen in 6 rabbits in the control group and 3 in the Catalin group; the degree of PCO was higher in the placebo group. CONCLUSION: We found that Catalin played some role in preventing PCO.

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BACKGROUND AND OBJECTIVE: To assess the efficacy of the newer surgical technique of sclerokeratoplasty in spherical anterior staphyloma of the cornea and to compare it with total penetrating keratoplasty. PATIENTS AND METHODS: A randomized, prospective clinical trial in 20 eyes with acquired spherical anterior staphylomas was undertaken. Ten eyes each underwent sclerokeratoplasty (group 1) or total penetrating keratoplasty (group 2). The parameters evaluated were visual acuity, keratometry, graft status, and complications. Patients were observed for a minimum of 1 year. RESULTS: Best spectacle-corrected visual acuity of 6/60 or better with astigmatism of less than 3 D was achieved in all but one patient in group 1 in contrast to 5 cases in group 2. Postoperative complications included epithelial defects, shallow anterior chamber, hyphema, and uveitis, which did not significantly vary between the 2 procedures. Secondary glaucoma was significant associated with group 2 as compared with group 1. At the end of 1 year, no significant difference in the graft clarity was present. Grafts were clear 3+ or more in 8 eyes in group 1 and in 5 eyes in group 2. Good cosmetic results were achieved in cases of sclerokeratoplasty due to the absence of corneal opacification and suture marks. CONCLUSION: Sclerokeratoplasty is a useful alternative to total penetrating keratoplasty in cases of acquired spherical anterior staphylomas of the cornea with good anatomic and useful visual outcome.

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PURPOSE: To compare manual phacofracture and phacoemulsification techniques. SETTING: Dr. Rajendra Prasad Centre for Ophthalmic Sciences, New Delhi, India. METHODS: This prospective, randomized study comprised 60 cases of age-related cataract randomly divided into 2 groups: 30 eyes had phacoemulsification and 30, manual phacofracture using a trisection technique. Postoperative evaluation was at 1 day, 1 and 6 weeks, and 3 months. The parameters evaluated were amounts of viscoelastic material and irrigating fluid used, the time required to manage the nucleus, postoperative best corrected visual acuity, endothelial cell loss, and complications. RESULTS: Mean viscoelastic material used intraoperatively (3.69 mL +/- 0.81 [SD] versus 1.76 +/- 0.54 mL) and the time required to manage the nucleus (7.78 +/- 2.07 minutes versus 2.53 +/- 1.18 minutes) were significantly greater in the phacofracture than in the phacoemulsification group, respectively. Best corrected visual acuity was significantly better in the phacoemulsification group on the first postoperative day; 64% had a visual acuity of 6/9 or better versus 37% in the phacofracture group. Endothelial cell loss at 3 months was 17.66 +/- 3.65% in the phacofracture group and 12.03 +/- 3.06% in the phacoemulsification group and central corneal edema persisting for more than 1 week, 7 and 0 cases, respectively. The differences between groups were statistically significant. CONCLUSION: More experience in and further modification of the manual phacofracture technique are required before it can be recommended as a safe alternative to phacoemulsification.

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Sixty cases of traumatic cataract in 5 years due to occupational and environmental hazards were studied to highlight mode of trauma, structural damage; management profile and final visual outcome. Thirty six (60%) cases had mechanical trauma whereas 18 (30%) cases had injuries due to non metalic or organic substances. Industrial accidents were responsible in 25 (41.66%) cases. Forty four cases (73.3%) had associated anterior segment injuries. Reconstruction of anterior segment with Posterior Chamber Intraocular lens (PC IOL) implantation could be done in 42 (70%) cases as primary or secondary procedure. Adherent leucoma, iridal trauma, posterior capsular tear and dislocated lens were noted problems. Forty six (76.67%) cases had attained 6/12 or better corrected visual acuity. Defective visual gain was due to corneal opacities and post operative complications.

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The prevalence of blindness in India is 14.9 per 1000. Eighty per cent of this blindness is due to cataract alone. Most of the cataract blinds in the country are in the rural areas while the surgical service delivery network is concentrated in the urban areas. Thus a large proportion of patients in the rural areas continue to remain blind. This situation has many social implications. There is loss of productivity, breakdown of interpersonal relationships, depressive manifestations, loss of self esteem and most patients lead an isolated humiliating life. Patients lack information on the available services and continue to remain blind for years even after being diagnosed as operable. This is unfortunate because cataract surgery is one of the most cost effective health interventions known and most operated patients, irrespective of the surgical technique, are immensely satisfied with the level of visual rehabilitation after surgery.

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A prospective clinical trial of topical fluconazole solution (2 mg/ml) was undertaken in six consecutive eyes of microbiologically proven Candida keratitis with abscess formation. All eyes responded well to the medical therapy. Average duration required for healing was 22.6 +/- 2.3 days. The findings of our study suggest that topical fluconazole is a safe and effective antifungal drug for the management of Candida keratitis with deep abscess.

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We describe a modified surgical technique of anterior capsulotomy and phacoemulsification for use in hypermature cataracts. Surgical steps included inferior linear capsulotomy with aspiration of milky cortex, inflation of the capsular sac with viscoelastic, a reverse triangular anterior capsulotomy with Vannas scissors, and in-the-bag bimanual sculpting of the nucleus. An oval 5 mm x 6 mm posterior chamber intraocular lens was used with single horizontal or no-stitch wound closure. The technique was used successfully in 20 cases of hypermature cataract. The mean time required to perform phacoemulsification was 3.46 minutes (range 1.2 to 6.3 minutes), with a standard deviation of 1.29. Visual acuity on the first postoperative day ranged from 20/20 to 20/60 (median 20/40). At one week, the mean astigmatism was 1.01 diopters (range 0.25 to 2.75 diopters). The mean endothelial cell loss was 13% (range 3.6% to 26.0%). Based on our results, the modified phacoemulsification technique merits consideration for use in hypermature cataracts.

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Some uremic patients with a history of blood transfusion, pregnancy, and previous transplantation maintain high levels of alloreactive cytotoxic antibodies in the absence of continuous exogenous allogenic stimuli and are thus considered sensitized to the major histocompatibility proteins. To differentiate into antibody-producing cells, B lymphocytes must interact with T-helper (CD4+) cells. Whether ongoing help from these cells is necessary for the B cells to continue producing cytotoxic alloreactive antibodies in these sensitized uremic patients is unknown. To gain insight into the cellular mechanisms that are associated with sustained alloantibody production, T cell activation markers were measured and specific and nonspecific T-helper cell function was studied in three uremic groups with different levels of panel reactive antibodies: 10 patients whose sera reacted to more than 80% of a panel of normal lymphocytes for at least 6 months before the study were highly sensitized, 20 patients whose sera reacted to less than 80% of the panel were moderately sensitized, and 10 nonsensitized patients whose sera did not react to any cell on the panel. The number of total and activated T-helper cells was similar in the highly sensitized and nonsensitized patients. Peripheral blood lymphocyte proliferation in response to plant lectins, soluble OKT3, or alloantigens was similar in the three uremic groups. The spontaneous proliferation of pure T-helper cells and proliferative responses to immobilized OKT3 or alloantigens were also similar in highly sensitized and nonsensitized patients. Alloreactive interleukin-2-producing cell frequencies with pure CD4+ cells as responding cells were 771 +/- 77.9/10(6) cells in highly sensitized, 945 +/- 252/10(6) cells in nonsensitized, and 973 +/- 114/10(6) cells in controls (P = not significant). Panel reactive antibody levels did not correlate with any of the measures of T helper responses. There was a significant decrease of peripheral blood lymphocyte responses to alloantigens and anti-CD3 antibody in all uremic patients as compared with normals, suggesting a dysfunction in accessory cells that was quantitatively similar in sensitized and nonsensitized patients. In spite of the continuous production of alloantibodies by B cells, there is no evidence of either specific or nonspecific enhancement of T-helper cell function in sensitized patients. The absence of T cell immunity to alloantigens suggests that sustained activation of T-helper cells with subsequent interleukin-2 production is not necessary to maintain alloreactive B cell function.

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We analyzed the characteristic features and intraoperative behavior of pre-existing posterior capsule breaks in 12 cases of traumatic cataract caused by perforating ocular trauma. The interval between the occurrence of trauma and cataract surgery ranged from three days to one year. Two distinct types of posterior capsule breaks were found: one had thick, fibrous, opaque margins with associated posterior capsule opacification (type I); the other had thin, transparent margins (type II). Type I breaks did not enlarge intraoperatively, whereas type II breaks behaved as fresh breaks by enlarging during irrigation/aspiration and had to be managed by viscoelastic plugging, dry aspiration, and adequate vitrectomy. Primary posterior capsulectomy was required in all cases with type I breaks because of posterior capsule opacification. The difference in the two types of breaks appeared to be time-dependent: cases with delayed surgical intervention (one month to one year) showed type I breaks with clinical evidence of attempted healing of the defect; cases with early surgical intervention (three days to one week) exhibited type II breaks, which did not differ from fresh intraoperative breaks.

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Over a period of two years we performed combined penetrating keratoplasty, cataract extraction, and intraocular lens implantation in seven children between the ages of 2 and 12 years old. The interval between trauma and the surgery varied from six weeks to six months (3.5 +/- 1.6 months, mean +/- SD). All of the patients had undergone primary repair of corneal perforation. Fresh corneas preserved in McCarey-Kaufman medium were used. The graft size was 7.5 mm with 0.5 mm disparity. Posterior chamber polymethylmethacrylate C-loop lenses were used in all cases. The surgeon's average postkeratoplasty keratometry was used in the calculation of intraocular lens power. The follow-up period ranged from nine to 36 months (18 +/- 9.1 months, mean +/- SD). Six grafts remained clear at the final follow-up. The visual acuity ranged from 20/40 to 20/200 with final astigmatism ranging from 0.5 diopter to 2.0 diopters. One patient developed a retinal detachment 12 months after surgery, which was successfully reattached. One patient, who had preoperative corneal vascularization, had graft rejection, which was treated medically. Our limited series suggests that the triple ocular procedure is a good choice for the treatment of corneolenticular trauma in children. The proper postoperative treatment includes vigorous antiamblyopia therapy and Nd:YAG laser treatment of after-cataracts.

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Adherent leukomatous corneal opacities constitute the bulk of cases undergoing keratoplasty in developing countries. Surgical trauma to the iris resulting in a large iris coloboma, iridodialysis, and bleeding are the imminent intraoperative complications in such cases. We have evolved a technique of lamellar separation of corneal layers and gentle separation of adherent iris after partial trephination in such cases. We have successfully used this technique in six cases of adherent leukoma. No intra-or postoperative complication related to lamellar separation was encountered, and all the grafts remained clear at the end of 3 months.

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Contaminating microbial flora and their in vitro antibiotic sensitivity pattern was determined for 1557 eyes from donor cadavers collected during five years. Positive cultures were obtained in 42.77% of the eyes; bacterial growth was observed in 39.17% of the eyes and fungal growth, in 3.6%. There was significant variation in the rate of contamination from year to year during the study period. Staphylococcus albus was the most frequently isolated organism (28.10%), followed by Acinetobacter spp., Pseudomonas aeruginosa, and Alcaligenes faecalis, respectively. Most of the organisms were resistant to commonly used antibiotics with a low weighted index of effectiveness, particularly toward gentamicin (resistance, 50.82%). The findings were compared with previous data from the same eye bank, and the variations are discussed.

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Corticosteroid-resistant deposits on the anterior surface of intraocular lenses (IOLs) in 11 patients who had complained of poor vision were "swept" with a Neodymium:YAG laser beam. As contrasted with previous "direct hit" methods, our method is indirect, using a low-power, defocused beam to generate an acoustic shock-wave, which then sweeps the lens surface clear of deposits. The deposits were cleared in all 11 patients, with no damage to the IOL or any other postlaser complications. Improvement in visual acuity ranged from 1 to 3 lines, and all the patients reported alleviation of symptoms.

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In a prospective study, we evaluated the sensitivities of direct microscopy using potassium hydroxide 10% wet-mount preparations and culture for definitive diagnosis of keratomycosis in 171 clinically suspected fungal corneal ulcers. Although cultures were positive in 88 eyes (51.46%), the fungus could be demonstrated by KOH preparation in 94.3% (83 of 88) of the culture-proved cases and 93.6% (160 of 171) of the overall eyes. Direct microscopic examination of a KOH wet-mount preparation is a rapid, reliable, and superior technique of laboratory diagnosis. It is particularly important for the early initiation of antifungal treatment in mycotic keratitis.

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Cryotherapy of the palpebral conjunctiva with oral aspirin has been evaluated in mixed-type active vernal keratoconjunctivitis. The symptoms and signs were recorded on a four-point scale. In 15 patients, we used cryotherapy of the palpebral conjunctiva in 30 eyes (-60 degrees C to -80 degrees C for 30 seconds, repeating the freeze-thaw cycle 2-3 times). All patients received oral aspirin 0.5 to 1.5 g in three divided doses daily over six weeks. The relief from symptoms was statistically significant (P less than .001). Objective improvement (palpebral and bulbar signs) also was statistically significant (P less than .001). Follow-up of these cases for one year showed a 3.3% recurrence rate.

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We report a modified technique of direct scleral fixation of a posterior chamber intraocular lens (PC-IOL) using a specially designed intraocular needle-holder. The procedure was carried out in three eyes with posttraumatic subluxated cataracts; one with aphakic bullous keratopathy and with an accidental posterior capsular rent, and one with a superior zonulodialysis. The needle-holder greatly facilitated the procedure, enabling us to place the PC-IOL precisely in the ciliary sulcus with no subsequent decentration. This method avoids iris fixation and provides more secure scleral fixation of the PC-IOL.

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Clinically observed complicated cataracts, generally do not have a definite causal factor. We studied the effects of E. coli toxin injected suprachoroidally, to simulate the effect of toxins released by extraocular organisms on the lens. 79.2% of eyes had a definable cataract at the end of the 6th week of observation. The biochemical changes portrayed an increased oxidative activity in the lens, evidenced by a fall in glutathione concentration, and the consequent tertiary reorientation of proteins to increase insoluble proteins, forming a cataract.

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