Identification of glaucomatous optic nerve head changes in Indian donor eyes without clinical history.

Purpose: The purpose of this study is to develop methods to identify glaucoma by examining the optic nerve head (ONH) of donor’s eyes when information on the preexisting ocular disease is unavailable. Materials and Methods: The ONH of the donor’s eyes was evaluated under a stereomicroscope for the cup‑disc ratio (CDR) and focal retinal rim thinning. The vertical diameter of the cup and disc was also measured using a precalibrated eyepiece micrometer. The suspect eyes were subjected to histological analysis to confirm the presence of specific glaucomatous changes. Results: A total of 202 eyes from 119 donors (68 males and 51 females, aged 42–96) were evaluated for glaucoma. Among them, 190 (94%) eyes showing vertical CDR in the of 0.0–0.6 range were considered nonglaucomatous and the remaining eyes with >0.6 as glaucoma suspect. The calculated mean CDR of the two groups (0.3 ± 0.16, 0.62 ± 0.27) was highly significant (P = 0.0003). Of 12 eyes suspected of glaucoma, 7 eyes from 5 donors showed specific glaucomatous changes by histology. The prevalence of glaucoma was 4.2% among the donors studied. Conclusions: A simple method of screening fresh donor eyes for selecting those with glaucoma features using CDR and histological analysis was reported. This method helps to obtain biologically active human ocular tissue for glaucoma research on gene expression, ultrastructural/proteome changes, and outflow mechanism.

A pilot study on the infiltrating cells and cytokine levels in the tear of fungal keratitis patients.

AIM: To determine the cellular profile and cytokine levels in the tear fluid of fungal keratitis patients. MATERIALS AND METHODS: Tear samples were collected from six fungal keratitis patients (Group I) from active stages of the disease up to resolution. Tears collected from the following served as controls: uninfected fellow eye (Group II A) of Group I, patients undergoing cataract surgery (Group II B) and acute conjunctivitis (Group II C). The cellular profile was evaluated. Interleukines (IL-6, IL-8 and IL-1beta) were estimated using sandwich enzyme immunoassay. Statistical analysis was carried out using nonparametric two-sample median test. RESULTS: Polymorphonuclear leukocytes (PMN) were the predominant infiltrating cells in Group I. During the initial stages of fungal infection, levels of IL-6 and IL-8 in the tear samples were found to be significantly increased when compared with Group II A (P=0.019 for IL-6, P<0.001 for IL-8). This was also true for IL -8 (P=0.008) levels in Group I and Group II B). While IL-6 levels decreased significantly towards healing, IL-8 remained slightly elevated even after healing. These cytokines were at the base level in Group II A. Lymphocytes and PMN were present in equal proportions in Group II C, which showed elevated levels of cytokines but not to the extent of Group I. CONCLUSION: This horizontal study indicates that understanding the nature of the inflammatory response in the tears of fungal keratitis patients is of considerable interest and warrants further investigations.

Immune status of health care personnel & post vaccination analysis of immunity against rubella in an eye hospital.

BACKGROUND & OBJECTIVES: Congenital rubella syndrome (CRS) accounts for a significant amount of mortality and morbidity in India. Rubella vaccination is not included in our national immunization programme. Occupational exposure of the health care personnel to rubella infection is well known. This study aims to assess the serological status of health care workers against rubella virus in Aravind Eye Care System, Madurai and to follow the immune response in the seronegative individuals after vaccination. METHODS: A total of 500 female and 81 male workers were enrolled in the study. Blood sample was collected for the analysis of rubella specific IgM and IgG antibodies. The seronegative individuals were vaccinated with monovalent rubella vaccine, RA 27/3. The post-vaccination samples were analysed for the antibody levels and their avidity using enzyme immunoassay. RESULTS: Of the 581 volunteers, 493 were seropositive with good protective immunity and 22 had both IgM and IgG antibodies. Sixty six volunteers (59 females and 7 males) were found to be seronegative to rubella. The seroconversion was observed in all the sixty vaccinated individuals, as seen by the appearance of anti-rubella IgG antibodies by fourth week, reaching the peak protective levels (>20 IU/ml) by third month. There was also a progressive increase in the avidity after vaccination. INTERPRETATION & CONCLUSION: Nearly 11.4 per cent of the health care workers were found to be seronegative for rubella virus and after vaccination, these volunteers developed a good protective immunity, thereby reducing the risk of contracting the hospital based rubella infection. Therefore, rubella vaccination may be instituted in hospitals for the benefit of health care workers.