Pediatric Glaucoma

Pediatric Glaucoma: Intro & Types - Tiny Eye Pressure

• Optic neuropathy in children, often from ↑ Intraocular Pressure (IOP), leading to irreversible vision loss; early detection is key.
• Types:
  • Primary Congenital Glaucoma (PCG): Developmental anomaly of trabecular meshwork. Onset birth to <3 years.
    • True congenital: IOP elevated in utero.
    • Infantile: Presents by 1-2 years.
  • Juvenile Open-Angle Glaucoma (JOAG): Onset >3-4 years up to 35 years.
  • Secondary Glaucomas: Result from other conditions (e.g., uveitis, trauma, syndromes, steroid-induced).

⭐ Haab's striae (breaks in Descemet's membrane due to corneal stretching) are a pathognomonic sign of PCG presenting before age 2-3 years an exam favourite!

Pediatric Glaucoma: Pathophysiology & Genetics - Faulty Faucets

• Pathophysiology: Trabeculodysgenesis (maldeveloped aqueous outflow pathways).
  • Abnormal Schlemm's canal & trabecular meshwork.
  • Leads to ↑ Intraocular Pressure (IOP).
• Genetics: Key genes involved:
  • CYP1B1: Most common in Primary Congenital Glaucoma (PCG).
  • LTBP2, TEK (TIE2): Also linked to PCG.
  • MYOC: Associated with Juvenile OAG (JOAG).

⭐ CYP1B1 mutations are the most common genetic cause for primary congenital glaucoma (PCG).

Pediatric Glaucoma: Clinical Features - Tears & Big Eyes

• Classic Triad: 📌 EPB
  • Epiphora (persistent, watery eyes)
  • Photophobia (marked light sensitivity)
  • Blepharospasm (forceful eyelid closure)
• Key Signs of ↑IOP:
  • Buphthalmos ("ox eye"): Globe enlargement. Corneal diameter > 12mm at birth (increases with age).
  • Corneal edema/haze: Cloudy cornea, may obscure iris details.
  • Haab's striae: Horizontal/curvilinear tears in Descemet's membrane.
  • Elevated IOP: Typically > 21 mmHg.
  • Optic disc cupping: Progressive, initially reversible.
  • Axial myopia and astigmatism.

⭐ Haab's striae are a hallmark of congenital glaucoma, indicating corneal stretching due to elevated IOP.

Pediatric Glaucoma: Diagnosis - Anesthesia Peeks

Examination Under Anesthesia (EUA) is key for diagnosis.

• Tonometry: Perkins (gold standard), Tonopen. IOP > 21 mmHg or asymmetry > 5 mmHg suspicious.
• Corneal Diameter: Horizontal. > 11 mm (birth), > 12 mm (1 yr), or > 13 mm (any age) abnormal.
• Gonioscopy: Direct (Koeppe, Swan-Jacob) for angle structures.
• Ophthalmoscopy: Optic disc. C/D ratio > 0.3, asymmetry > 0.2, progressive cupping.
• Axial Length: A-scan. ↑ indicates globe stretching from ↑IOP.
• UBM: If corneal opacity obscures anterior segment.

⭐ Haab's striae (breaks in Descemet's membrane) are pathognomonic for congenital glaucoma.

Pediatric Glaucoma: Management - Surgical First

Surgery is primary; medical therapy is often adjunctive/bridging.

• Angle Surgery (1st Line):
  • Goniotomy (clear cornea)
  • Trabeculotomy (cloudy cornea)
• Alternatives (if angle surgery fails/unsuitable):
  • Combined Trabeculotomy-Trabeculectomy (CTT)
  • Trabeculectomy + antifibrotics (MMC/5FU)
  • Glaucoma Drainage Devices (GDDs)
• Last Resort: Cyclodestructive procedures.

• Medical Therapy:
  • Topical: Beta-blockers, CAIs.
  • Systemic: CAIs.
  • ⚠️ AVOID alpha-2 agonists (infants/young children) - CNS depression risk.

⭐ Goniotomy is preferred for clear corneas; trabeculotomy if cloudy, allowing direct Schlemm's canal access.

High‑Yield Points - ⚡ Biggest Takeaways

• Buphthalmos (corneal diameter > 12 mm at 1 year) and Haab's striae (Descemet's breaks) are key signs.
• Primary Congenital Glaucoma (PCG) is most common, often bilateral, with autosomal recessive inheritance.
• Classic triad: epiphora, photophobia, blepharospasm; also corneal edema/haze.
• Diagnosis: Elevated IOP (> 21 mmHg), progressive optic disc cupping (C:D > 0.3 or asymmetry).
• Treatment: Primarily surgical; goniotomy or trabeculotomy are preferred procedures.
• Associated syndromes include Sturge-Weber, Neurofibromatosis, and Axenfeld-Rieger.