Congenital Glaucoma

Dr Vinit Sankhe / Dr Nita ShanbhagD.Y.Patil Medical College & research Center

Epidemiology & Evaluation• External examination• Corneal Assessment• Refraction• Slit lamp examination or

examination under µscope• Tonometry• Gonioscopy• Ophthalmoscopy• Ocular fundus photo• Ultrasound ocular

biometry with Pachymetry

EPIDEMIOLOGY

• Incidence: 1 in 30,000 live births

• Age -- birth to age 3; more severe with earlier onset

• Gender -- 65% male • Genetics: Majority of

cases sporadic – Some autosomal recessive

• Chromosome 1p36 and 2p21 (CYP1B1)

Corneal diameter is enlarged in LE

Increased tear lake in the affected eye

Classic Triad: Photophobia, Epiphora, BlepharospasmCorneal "clouding" may be evident to the parent

• 75% bilateral • Immature angle with high iris insertion

– failure/arrest of angle development • Buphthalmos • Increased horizontal corneal diameter

– Normal 10.0 - 10.5 mm; >12 mm suggestive of infantile glaucoma • Corneal Edema (25% at birth, 60% at 6 months age) • Haab's Striae

– Tears in Descemet's membrane, usually horizontal or radial • Deep anterior chamber • Cup to disk ratio >0.3 • Axial myopia

Signs

Genetics• Heritable mutations in cytochrome P4501B1

gene ( CYP1B1) is the principle cause of congenital glaucoma in families linked to the GLC3A locus on chromosome 2p21– 13 bp deletion in exon III– Insertion of a single cytosine base in exon II– Larger deletion affecting the 5’ end of exon

III

Ivaylo Stailo, A. Nurten Akarsu, Human Molecular Genetics 1997, Vol 6, No 4, 61 - 67

Corneal CloudingCo Diameter = 11 mmAniridiaStem cell deficiencyPre op IOP = 50.6

Co clearingPost op IOP = 17.3

Management• The choice and success of the operative procedure depends on

– The duration of raised intraocular pressure,

– Presence of corneal opacity and enlarged corneal diameter.• Exam under anesthesia (EUA) is first required to confirm

diagnosis

• When the corneal diameters are increased and advanced corneal changes have set in, precluding procedures like goniotomy & goniopuncture the operation of trabeculotomy ab externo with trabeculectomy is tried.

• Sood NN, Aggarwal HC, Kalra BR. Evaluation of surgery for congenital glaucoma. Indian J Ophthalmol 1983;31:609-11

Steps of Trabeculectomy with trabeculotomy

Pre opCorneal clouding

Post opCornea cleared

Scleral Flap – MMC Dissect upto the grey limbus

Trab meshwork cut Diffuse bleb subconjunctival

Pre opCorneal clouding

Post opCornea cleared

Treatment …..• Surgical treatment:

– Trabeculotomy - Gold StandardIkeda et al (Arch Ophthalmol, 2004) reported 5, 10, and

15 year success rates for treating congenital glaucoma as 100%, 85.7%, and 77.9% respectively. Infantile glaucoma success rate was 96.6% for all years.

– Goniotomy - Similar success rates as trabeculotomy – Combined trabeculotomy and trabeculectomy – Trabeculectomy or seton - mostly for cases refractory

to goniotomy or trabeculotomy

……Treatment• Filtering surgery is shown to have less success in

children and youngsters than in adults. – Greater anatomic complexity– Marked conjunctival and scleral fibrovascular response – Difficult postoperative follow-up.

• Trabeculectomy with trabeculotomy is the surgery of 1st choice augmented with MMC– MMC complications are to be observed with good FU

• Recent advances advocate Implants as the 1st choice

• Supplemental medical therapy with topical medications may be indicated

Disc Cupping in CG• In the early stages of congenital glaucoma, the rapid increase of

cupping can be explained by the distention of the optic disc and of the lamina cribrosa with enlargement of the scleral canal and loss of intracellular as well as intercellular fluid. Besides that, at a later stage, there will be loss of glial tissue and atrophy of neurons as well.

• The beginning of the reversal of cupping occurred by 6 weeks after the surgical procedure had taken place.

• The younger the children at the time of surgery, the higher the rate of cupping reversal.

• In childhood glaucoma, the fast adoption of surgical procedure allows the reduction of the IOP and the consequent reversal of the optic disc cupping.

Evaluation of the Factors Associated With the Reversal of the Disc Cupping After Sx Treatment of Childhood Glaucoma, Se´rgio Henrique J Glaucoma 2008;17:470-473

Discussion• The delay in the diagnosis of congenital glaucoma lead to the

enlargement of corneal diameter over 13 mm., development of corneal changes and fundus changes. This makes the visual prognosis poor.

• Awareness among the obstetricians, pediatricians and practitioners for early detection so that these patients can be referred to institutions for early management before gross damage to eye occurs.

Agarwal HC, Sood NN, Kalra BR. Clinical presentation of congenital glaucoma. Indian J Ophthalmol 1983 [cited 2009 Sep 1];31:619-22.