The Ibadan glaucoma study.

To obtain epidemiological data on the prevalence and risk factors for open angle glaucoma in hospital workers of African origin, and investigate appropriate methods of a rapid, cost-effective screening procedure for glaucoma. A cross-sectional study of workers in the University College Hospital (UCH) Ibadan, using a structured questionnaire for data collection. The variables available for data analysis include workers demographic characteristics, visual acuity, pupil status, intraocular pressure, cup-disc ratio, central visual fields, family history of glaucoma, chronic diseases such as hypertension and diabetes. The data was analysed with EPI-INFO version 6.02 for simple analysis, while the SPSS package was used for multivariate analysis. A total of two thousand, one hundred and nine (2,109) UCH workers participated in the screening exercise for glaucoma. A high majority of the workers 1794 (85.1%) were negative to the diagnosis of glaucoma, while the remaining 315 (14.9%) were suspected to have glaucoma out of which 57 (2.7%) were confirmed as definite glaucoma cases. The prevalence of glaucoma among UCH workers was 27 per 1000, 95%, confidence interval = 20 per 1000, 35 per 1000. Factors associated with glaucoma were relative afferent pupillary defect, cup-disc ratio greater than 0.7, intraocular pressure, family history of glaucoma and the presence of chronic diseases such as diabetes. The left eye appears to have a higher probability of ocular problems compared with the right eye. The prevalence of glaucoma among hospital workers was 2.7% The cup-disc ratio appears to be a better diagnostic tool for glaucoma since it gives the best positive predictive value (with a cut-off point of 0.7) than all other variables.

A comparison of visual function scores in hydrocephalic infants with and without lumbosacral myelomeningocoele.

PURPOSE: The cerebrum is frequently malformed in children with myelomeningocoele. This anomaly renders them potentially susceptible to cerebral visual impairment. In these patients, hydrocephalus is an important and frequent complicating lesion which compromises intellectual function and may also cause cerebral visual impairment. In this study, we determined whether hydrocephalic patients with lumbar myelomeningocoele (HLM) are at a greater risk of visual impairment than hydrocephalic patients without this lesion (H). METHODS: In this prospective study, we assessed five parameters of visual function in 20 hydrocephalic children with lumbar myelomeningocoele and compared the total visual function scores (TVFS) obtained with those from hydrocephalic children without overt spinal dysraphism, but similar in age, sex and ventricular size. The parameters, which were assessed with the aid of a quantitative grading scale, were pupillary size and reaction, optic atrophy, visual fixation and tracking. RESULTS: The age and sex distributions of the patients in the two groups were similar. The anterior and posterior dimensions of the lateral ventricles were also similar. The mean (SD) of the TVFS were 24.25 (3.63) and 24.20 (3.47) respectively for the two groups (P = 0.90). CONCLUSIONS: The results suggest that, in hydrocephalic infants with lumbar myelomeningocoele, visual function is not further diminished by the associated dysraphism and that ventricular dilatation is the major determinant of visual impairment.

Trabeculectomy in young Nigerian patients.

The results of 89 trabeculectomies performed on 56 patients under the age of 30 years were reviewed. Data collected included age, sex, type of glaucoma, number of years of glaucoma before surgery, visual acuity, intraocular pressure, complications of surgery, presence of a filtering bleb and follow-up period. Complete success, denoted by a postoperative IOP of 21 mmHg or less without medical therapy, occurred in 50 eyes (56.2%). Qualified success, in which IOP was 21 mmHg or less with additional medical therapy occurred in 31 eyes (34.9%) and failure, in which IOP was greater than 21 mmHg in spite of medical treatment occurred in 8 eyes (8.9%). Success was therefore achieved in 91.1% attaining an IOP of 21 mmHg or less, with or without additional medical therapy. The most statistically significant factor was age groups in which the highest success rate of 100% was achieved in the age group 20-29 years. The difference in the success rate across the age groups was statistically significant (x2 = 8.04, p = 0.01). Fornix based conjunctival flaps were also found to be associated with a statistically significant higher success rate (97.9%) as opposed to limbal based flaps (85.4%), x2 = 4.81, p = 0.03. Males in the study group had a significantly higher success rate (97%) than females (78.3%), x2 = 5.86, p = 0.011. A success rate of 100% was recorded in patients with developmental glaucoma, 86.1% in congenital glaucoma and 33.3% in secondary glaucoma. All the repeat trabeculectomies had congenital glaucoma. The presence of a bleb, although it had a higher success rate (93.4%) compared with the absence of a bleb (84.6%), was not statistically significant (x2 = 1.19, p = 0.27). Complications of surgery were mostly transient.

Effectiveness of trabeculectomy on glaucoma patients in Ibadan.

This study was designed to determine the effectiveness of trabeculectomy on African patients. All patients who underwent trabeculectomy over a 10-year period, January 1987 to December 1996 were included in the study. Information extracted from their case notes sex, included age, type of glaucoma, number of years of glaucoma before surgery, eye involved, and visual acuity pre-operatively and post-operatively. Intraocular pressures at presentation, pre-operatively and post-operatively (2 days, 1 week, 3 months, 6 months, 12 months and last clinic visit) were also recorded. Other data collected included pre-operative antiglaucoma therapy, additional techniques at surgery, complications of surgery, presence of a filtering bleb and follow-up period post operatively. A success rate of 91.2% was obtained from 433 eyes operated upon. The most significant outcome was the presence of a filtering blob which had a better success rate than the absence of a bleb. High success rates were recorded in the age groups "> 60 years and 20-40 years", the lowest success rate was in the "less than 20 years of age". All the patients with developmental glaucoma had a successful outcome (100%) while only 50% of the secondary glaucoma were successful. Patients with open angle glaucoma had 92% success rate. Complications of surgery were mostly transient. It was concluded that the presence of a bleb was a good indication of the control of intraocular pressure and that early surgery gave a more successful outcome than late surgery.

The relationship between ventricular size and visual function in children with hydrocephalus.

We examined the relationship between ventricular size and visual function in 50 children (36 males and 14 females) with hydrocephalus. The third and lateral ventricular sizes and the visual function scores did not significantly differ between the sexes. Ventricular enlargement was most pronounced at the trigones and least at the level of the foraminae of Monro. The visual function score correlated inversely with the size of the lateral ventricle measured at the levels of the anterior horn and the trigone and expressed as coronal diameter and "Modified" Evans' ratio (r = 0.49; P = 0.001 and r = -0.38, P = 0.01 for the anterior horn; r = 0.48, P = 0.001 and r = -0.35, P = 0.001 for the trigone). The size of the third ventricle did not correlate with visual function score. A "modified" anterior Evans ratio of 0.60 and a trigonal Evans ratio of 0.73 were associated with very low visual function score. Furthermore, there was significant inverse correlation between occipitofrontal circumference (OFC) and visual function (r = -0.6379, P = 0.001), but OFC was not valuable for predicting visual function before the onset of head enlargement.