Primary
a) True congenital → high IOP in intrauterine life (40%) & born with ocular enlarge.
b) Infantile → before 3rd birthday (50 & of all cases)
C) Juvenile → 10 % of cases between 3-16 years of life
If manifestation before age of three eyeball enlarges also called Buph/hyrdrophthalamos
Pathogenesis
Trabeculodysgensis (maldevelopment) aqueous outflow is impaired → high IOP
Clinical features
- A) Corneal signs → oedema, enlargement and Descemet’s break
- b) Sclera → becomes thin and appears blue due to underlying Uveal tissue
- c) Iris→ may show atrophic patches
- d) lens becomes flattened due to stretching of zonules
- e) Optic disc may show cupping and atrophy
- F) IOP is not acute
Examination
- 1. Measure IOP by tonometer
- 2. Measurement of corneal diameter (callipers)
- 3.Ophthalmoscopy (optic disc)
- 4. Gonioscopy ( iris changes)
Treatment usually surgically
1.Goniotomy, passing of Barkan’s knife through limbus on temporal side and the knife is passed across the anterior chamber to the nasal part of the angle and an incision is made in the angle to open it up
2. Trabeculotomy (and trabeculectomy)
→ When corneal oedema block Schlemm’s canals view or Goniotomy has failed →a vertical scleral incision is made at 12o clock after formation of conjunctival Trabeculotomy a becultome is inserted & rotated to break 1/3 of inner wall of Schlemm’s canal