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This paper presents some characteristics of the population genetics of primary congenital glaucoma in Slovakia. The overall incidence in Slovakia is 1:10,500, while being 1:1,250 in the Gypsy subpopulation of Slovakia and 1:22,000 in the non-Gypsy population. For a special type of congenital primary glaucoma, transmitted by autosomal recessive inheritance in Gypsies the gene frequency may be estimated to reach 2.8%. Early onset of the disease enabling diagnosis soon after birth in 82% of patients may be considered another characteristic of this type of primary congenital glaucoma.

Purpose: Our initial goal was to compare the efficacy and safety of a glaucoma drainage device and trabeculectomy for children with primary congenital glaucoma after angular surgery failure. However, we discontinued the study due to the rate of complications and wrote this report to describe the results obtained with the two techniques in this particular group. Methods: This was a parallel, non-masked, controlled trial that included patients aged 0-13 years who had undergone previous trabeculotomy or goniotomy and presented inadequately controlled glaucoma with an intraocular pressure ≥21 mmHg on maximum tolerated medical therapy. We randomized the patients to undergo either placement of a 250-mm2 Baerveldt glaucoma implant or mitomycin-augmented trabeculectomy. The main outcome measure was intraocular pressure control. We calculated complete success (without hypotensive ocular medication) and qualified success (with medication) rates. We defined failure as uncontrolled intraocular pressure, presence of serious complications, abnormal increase in ocular dimensions, or confirmed visual acuity decrease. Results: We studied 13 eyes of 13 children (five in the glaucoma drainage device group; eight in the trabeculectomy group). Both surgical procedures produced a significant intraocular pressure reduction 12 months after intervention from the baseline (tube group, 22.8 ± 5.9 mmHg to 12.20 ± 4.14 mmHg, p=0.0113; trabeculectomy group, 23.7 ± 7.3 mmHg to 15.6 ± 5.9 mmHg, p=0.0297). None of the patients in the tube group and 37.5% of those in the trabeculectomy group achieved complete success in intraocular pressure control after 12 months of follow-up (p=0.928, Chi-square test). Two patients (40%) had serious complications at the time of tube aperture (implant extrusion, retinal detachment). Conclusions: Both the tube and trabeculectomy groups presented similar intraocular pressure controls, but complete success was more frequent in the trabeculectomy group. Non-valved glaucoma drainage devices caused potentially blinding complications during tube opening. Because of the small sample size, we could not draw conclusions as to the safety data of the studied technique.

We report a further four cases of spontaneously resolved primary congenital glaucoma, including one case seen both prior and subsequent to the resolution. This condition is detected usually in eyes with megalocornea, which are later found to have breaks in Descemets membrane. Two other patients also had this diagnosis made, but later developed active glaucoma, requiring surgical treatment, indicating the need for continued observation of apparently abortive forms of congenital glaucoma.

A RETROSPECTIVE study of primary congenital glaucoma, over a 20 year period, is reported. There were 22 cases in 20 years, giving an incidence in Northern Ireland of 1: 22,000 live births. The male to female ratio was approximately 2 : 1 and 27% of cases were familial.

We report a prospective follow-up study of the axial length by ultrasonographic biometry in 15 eyes with congenital glaucoma. The mean age of the patients with primary congenital glaucoma was 5.3 ± 0.8 months at the diagnosis. All had an undeniable congenital glaucoma defined by means of applanation tonometry, biomicroscopy and ophthalmoscopic studies. The postoperative followup varied from 9 to 30 months. After successful glaucoma surgery a good control of intraocular pressure was also followed by initial decrease of the axial length, while after unsuccessful operation a continued increase of the axial length was noted. We conclude that ultrasonographic biometry is an additional valuable technique to be used routinely both at the diagnosis as well as postoperative follow-up of all congenital glaucomas.

Failure of filtering surgery is usually due to postoperative scarring of the filtering site. The scarring takes place usually on the external episcleral surface and hampers the outflow of aqueous humor through surgically created fistula (Addicks et al. 1983). Fibroblasts are known to be responsible for the scarring process. The excessive scarring is particularly prone to occur in some conditions which have consequently poor surgical prognosis. These include neovascular glaucoma, glaucoma in aphakia, primary congenital glaucoma and primary open-angle glaucoma in which previous filtering surgery failed repeatedly (Shirato et al. 1982).

PURPOSE: To investigate variations in sex ratio among Iranian primary congenital glaucoma (PCG) patients with and without mutations in the CYP1B1 gene and to evaluate possible clinical variations associated with sex in these two groups. METHODS: Phenotypical data on 104 unrelated Iranian PCG patients who had previously been screened for CYP1B1 mutations were analyzed. Emphasis was placed on analysis of sex ratios among patients with and without CYP1B1 mutations. In addition to sex, familial and sporadic incidence and clinical features including age at onset, bilateral/unilateral involvement, corneal diameter, intraocular pressure, and cup-disc ratios were compared between these two groups. Information on phenotypical parameters was available for most but not all patients. RESULTS: Among the 93 PCG patients whose sex was recorded, 57 were male (61.3%) and 36 were female (38.7%) (P=0.03). Patients with CYP1B1 mutations included 37 male (66.1%) and 29 female (43.9%) subjects (P=0.30), while patients without the mutation included 20 (74.1%) male and 7 (25.9%) female individuals (P=0.013). Our data did not provide conclusive evidence on difference in severity of the disease between those with and without CYP1B1 mutations, nor between the two sexes. CONCLUSION: Consistent with data on PCG patients from other populations, the overall incidence of PCG in Iran seems to be higher among male subjects. The difference in incidence between the two sexes was not significant among patients whose disease was due to mutations in CYP1B1. The overall higher incidence of PCG among male subjects seems to be attributable to a higher incidence in male patients not harboring CYP1B1 mutations, suggesting that other genes or factors may be involved in manifestation of PCG phenotypes in a sex dependent manner.

Glaucoma is a progressive optic neuropathy; increased intraocular pressure (IOP) is a modifiable risk factor for primary congenital glaucoma (PCG). Increase IOP causes retinal and optic nerve compression and leads to gradual and irreversible loss of eyesight if left untreated. It is the second most leading cause of blindness. PCG mainly affects children up to the age of three years, and symptoms include epiphora, photalgia, swollen eyes, opaque corneas, blepharospasm, rupture in the retina and ocular nerve damage due to IOP. Early detection, management, and treatment are the keys to preventing vision loss from glaucoma. Many mutations have been discovered in Cytochrome P450 1B1 (CYP1B1) gene to be responsible for causing PCG, and there are still a lot of mutations to be discovered. In this review, we will discuss the genetic aspects of PCG and the most frequent mutations responsible for PCG in Pakistani children. PCG can be handled by decreasing IOP either by medication or by surgery. Genetic counselling plays a significant role in the establishment of proper management of PCG.