[Epidemiologic study of refractive errors in schoolchildren in socioeconomically deprived regions in Tunisia]. / Epidémiologie des erreurs réfractives chez des enfants scolarisés, socio-économiquement défavorisés en Tunisie.

PURPOSE: This study's purpose was to estimate the prevalence of common refractive errors in schoolchildren in low socioeconomic regions in Tunisia and to assess their effect on school performance. MATERIAL AND METHODS: This was a cross-sectional study done from November 1999 to January 2000 within the context of health care screening campaigns carried out by volunteer ophthalmologists and opticians in low-end socioeconomic regions in Tunisia. The concerned population was schoolchildren living in the cities of Tunis and Tabarka (North), Kerkena (Center), and Tozeur (South). We examined a total of 708 children with a mean age of 11.9 +/-3.21 years (from 6 to 20 years) and a sex ratio of 0.84. A cycloplegic refraction examination was performed on all the children. Statistical analyses with the chi squared test and the Fisher exact test allowed us to calculate the prevalence of the refractive errors totally and separately as well as the distribution according to age, sex, and region. We also searched for a possible relation between refractive errors and academic failure. RESULTS: Among the 708 children, 57.2% [CI(95)=53.4-60] had refractive errors, of which 31.6% [CI(95)=28.2-35.2] were hyperopic, whereas 9.1% [CI(95)=7.1-11.5] were myopic. Astigmatism was found in 16.4% [CI(95)=13.7-19.3]. The prevalence of myopia was significantly higher after the age of fourteen. It increased significantly with age (P=0.0003). The prevalence of hyperopia was significantly higher between the ages of 8 and 11 (P=0.0004). Hyperopic astigmatism was significantly more frequent between 6 and 9 years of age (P=0.001). There was no significant difference regarding sex. However, the distribution of the refractive errors by region showed a significantly high level of myopia in Tunis, Kerkena, and Tozeur. This difference disappeared with increasing age. The study of the effect of these refractive errors on school performance of these children from poor areas showed a significant association between all types of refractive errors and academic failure, with an odds ratio of 2.13 for all types of refractive errors, 2.69 for hyperopia, 2.87 for myopia, and 2.73 for astigmatism. CONCLUSION: This study showed the prevalence of refractive errors in a poor population of schoolchildren and emphasized the importance of such examinations. The ability of a child to participate in the educational experience is at least partially dependent on good vision.

[Risk factors for secondary cataract: a case-control study with multivariate analysis]. / Les facteurs de risque de la cataracte secondaire.

AIM: A retrospective case-control study was initiated to determine the risk factors for the development of posterior capsule opacification. SUBJECTS AND METHODS: 100 cases of patients with secondary cataract treated by YAG laser capsulotomy were compared with 100 controls (patients who had cataract surgery not complicated with a secondary cataract). The posterior capsule was examined by the biomicroscope. A 1-to-1 matched case-control study was designed by stratifying inclusions on the basis of age, sex, and delay. We studied the risk factors related to the patient, the primary cataract, the surgical technique, the surgeon's skill, and intraoperative and postoperative complications. All the lenses were biconvex and all-PMMA with the same design. Statistical analysis was done in 3 steps: a univariate analysis, then a bivariate analysis using chi-square and the Student tests and finally, we performed a multivariate analysis with a logistic regression. The significance level for type I error rate was fixed at 5%. RESULTS: The average age was 61.6 years. The mean delay was 32.7 months for cases and 34.5 months for controls. The bivariate analysis identified nine risk factors: corneal opacities (p=0.031), absence of a posterior chamber lens p=10(- 4)), the can opener anterior capsulotomy (p=0.003), ciliary sulcus fixation of the lens p=0.030), a large optic diameter of 7mm p=10(- 5)) and (t=0.002), poor intraoperative pupillary dilatation (p=0.003), a less experienced surgeon (p=3.10(- 4)), postoperative inflammation (p=0.021), and persistence of residual cortical material (p=0.002). The multivariate analysis selected five principal factors: absence of a posterior chamber lens, an optic diameter of 7mm, poor intraoperative pupillary dilatation, a less skilled surgeon, and persistence of cortical material. CONCLUSION: This case-control study reveals some of the risk factors previously identified and may contribute to the determination of methods for prevention of secondary cataract. The new intraocular lenses and pharmacological agents would lead to better results.

[Prognostic outcome of leaking filtering blebs reconstruction with rotational conjunctival flaps]. / Pronostic fonctionnel des réfections de bulles de filtration perforées par lambeau de recouvrement conjonctivo-ténonien.

PURPOSE: Late bleb leaks may follow months to years after filtering surgery especially with the use of antimetabolites. Complications related to beb leaks may lead to a decrease in visual acuity through complicated hypotony or ocular infection. Our retrospective study reports the anatomical and functional results of bleb reconstruction involving the resection of the bleb associated with the covering of the trabeculectomy site with a rotational conjunctival flap. MATERIAL: and methods: Twelve eyes of eleven patients with filtering bleb leaks occurring 3 months to 5 years after successful trabeculectomy (58.3% with adjunct of antimetabolites) underwent bleb surgical reconstruction between november 1995 and June 1999 and were followed until March 2000. Surgical bleb reconstruction was indicated because of persistent or a recurring bleb leak despite conservative medical treatment and blood bleb injections in seven cases. Complications associated with bleb leaks were chronical hypotony (9 cases), athalamy (1 case), hypotony maculopathy (1 case), and endophtalmitis with athalamy (1 case). Three patients had normal IOP but a bleb leak responsible for epiphora. All eyes were treated surgically through bleb excision and conjunctival closure was performed by rotational conjunctival flap. RESULTS: Mean (+/- SD) preoperative IOP was 5.1+/-3.5mmHg (range: 2 to 14mmHg). Mean (+/- SD) postoperative IOP evaluated before any other operation for uncontrolled IOP was 12.7+/-3.1mmHg (range: 6 to 15mmHg). Mean follow-up was 26.7+/-16.9 months (range: 9 to 64 months). All the complications related to the bleb leak resolved after bleb reconstruction. Surgery definively stopped the leak in 10 cases (83.3%) and allowed IOP control without treatment in 50.0% of the cases. Chronic recurring bleb leaks without hypotony occurred in two eyes and required surgery with conjunctival graft which led to a refractory increase in IOP responsible for loss of vision in one case. CONCLUSION: Bleb resection associated with the covering of the trabeculectomy site with a rotational conjunctival flap is a safe and effective procedure for the treatment of a late bleb leak and its complications. In most of the cases (83.3%), long-term IOP control can be expected without, medical treatment in 50% of the cases. Patients must be aware of the possibility of a recurring Seidel; however, the incidence of this complication remains low.

[Malignant glaucoma and severe myopia. Report of a case]. / Glaucome malin et myopie forte. A propos d'un cas.

Malignant glaucoma is a rare and dramatic complication that occurs more frequently after glaucoma filtration surgery for angle closure glaucoma and rarely for open angle glaucoma. We report a case of a highly myopic monocular 38-year-old woman, with a primary open angle glaucoma who developed malignant glaucoma in the first postoperative days of a trabeculectomy. Treatment consisted of extracapsular cataract extraction and vitrectomy, with the removal of the anterior hyaloid and preventive circular buckling. Late postoperative events have been marked by the occurrence of anterior synechiae and residual hypertension. We discuss the pathogenesis of malignant glaucoma, its management and the results of the different therapeutic procedures.