01OverviewDefinition, clinical context and the essential points that orientate the chapter.
Congenital glaucoma is a sight-threatening disorder of the developing eye. In primary congenital glaucoma, abnormal development of the anterior chamber angle impairs aqueous outflow. The problem concerns fluid inside the globe; it is distinct from failure of tears to drain from the surface into the nose. Children can therefore have very watery eyes because the cornea is irritated by pressure-related oedema, rather than because the nasolacrimal duct is blocked.
The young globe responds differently from the adult eye. Elevated pressure can stretch the sclera and cornea, enlarge the eye and increase its axial length. Breaks in Descemet membrane, known as Haab striae, may accompany corneal oedema. The infant becomes light sensitive and may squeeze the eyelids shut. A parent may first comment that one eye looks unusually large or that the child dislikes daylight. Waiting for an infant to demonstrate adult-type peripheral field loss misses the early opportunity for diagnosis.
Primary congenital glaucoma may be sporadic or familial. Other childhood glaucomas are associated with anterior segment developmental abnormalities, aniridia, Sturge-Weber syndrome, uveitis, steroid exposure, trauma or previous cataract surgery. These conditions are not interchangeable: the mechanism, age at onset and treatment approach can differ. A relevant history should increase attention to eye follow-up, but an absent family history does not exclude primary disease and a known syndrome does not establish glaucoma without examination.
Specialist assessment may require examination under anaesthesia because an awake infant cannot reliably cooperate with all measurements. Pressure readings must be interpreted alongside corneal diameter and thickness, axial length, angle anatomy and optic nerve appearance. Crying, eyelid squeezing and anaesthetic conditions can influence measurement. The examiner records the technique and context rather than treating a single number as a complete diagnosis. Serial measurements become especially valuable when deciding whether the eye is continuing to enlarge or the nerve is changing.
Surgery usually provides the essential treatment for primary congenital glaucoma. Goniotomy or trabeculotomy aims to improve aqueous drainage through the abnormal angle; the precise technique depends on anatomy, corneal clarity and specialist expertise. Other operations may be needed if angle surgery does not achieve control. Medicines can support pressure reduction before or after surgery, but prescribing a familiar adult drop should not postpone surgical assessment. Long-term care also treats refractive error and amblyopia, which can limit vision even when pressure has improved.
Drug selection is particularly important in infants. Small body size and systemic absorption through the nasolacrimal route increase the significance of an apparently small topical dose. Brimonidine-containing products are contraindicated in children younger than two years and can cause profound central nervous system and respiratory depression. Other agents also need individual review of age, weight, respiratory and cardiac disease, kidney function and concomitant treatment. Families need a clearly written plan, demonstrated administration and advice about accidental exposure.
Key points
- Primary congenital glaucoma reflects abnormal development of aqueous drainage structures.
- The compliant infant globe can enlarge when intraocular pressure remains high.
- Epiphora, photophobia and blepharospasm are useful presenting clues.
- Haab striae are breaks in Descemet membrane associated with stretching.
- The diagnosis combines pressure, corneal, globe and optic nerve assessment.
- Angle surgery is central to treatment of primary congenital glaucoma.
- Brimonidine is contraindicated below two years of age.
- Successful pressure control still requires refraction, amblyopia care and lifelong review.
02AetiologyUnderlying causes, associations and risk factors, with why each one matters.
Developmental angle dysfunction
Abnormal formation of the trabecular outflow pathway increases resistance to aqueous drainage. In primary congenital glaucoma this occurs without another ocular disease sufficient to explain the pressure elevation.
Genetic susceptibility
Some primary congenital glaucoma is associated with inherited pathogenic variants, while other cases have no affected relatives. Genetic mechanisms and recurrence risk vary and require interpretation in the clinical and family context.
Other childhood glaucoma mechanisms
Anterior segment dysgenesis, previous cataract surgery, inflammation, steroids and systemic syndromes can cause childhood glaucoma. Their additional mechanisms distinguish them from isolated primary congenital disease.
03PathophysiologyThe causal sequence from the underlying abnormality to symptoms and harm.
- 1Pressure-related globe expansion
The immature cornea and sclera are relatively compliant. Sustained pressure can enlarge the globe and increase axial length, producing buphthalmos and a tendency towards myopic refractive error.
- 2Corneal oedema and breaks
Stretching can split Descemet membrane and disrupt corneal transparency. Oedema scatters incoming light and stimulates discomfort, photophobia, excessive tearing and forceful eyelid closure.
- 3Optic nerve injury
Raised pressure contributes to damage at the optic nerve head and loss of retinal ganglion cell function. The resulting visual deficit can coexist with optical blur and developmental amblyopia.
04Clinical features and red flagsSymptoms, examination findings, patterns of presentation and time-critical warnings.
Watch the infant's response to ordinary room light and compare the two eyes. Persistent lid squeezing or avoidance of light can reveal discomfort before formal examination begins.
Assess transparency and apparent size, looking for asymmetry or diffuse haze. Bilateral disease can make comparison falsely reassuring because both eyes may be abnormal.
Ask about cataract operations, inflammation, trauma and steroid treatment, including drops. Review existing specialist letters to distinguish primary glaucoma from a secondary mechanism.
Explore fixation, following and preference for one eye. Reduced engagement, squint or nystagmus may reflect impaired early vision but are not specific to glaucoma.
Ask about childhood glaucoma and related developmental conditions in the family. Relevant skin or anterior segment findings may prompt coordinated assessment and genetic advice.
05InvestigationsWhat to request, why it matters and how to interpret it.
Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.
- 01
Specialist tonometryFirst step - Why
- Measure intraocular pressure using an appropriate paediatric technique.
- Interpretation and limitations
- Record the instrument, cooperation and anaesthetic context where relevant. Interpret pressure with structural findings and trends; a difficult or isolated measurement should not overrule concerning clinical signs.
- 02
Corneal examination and measurements - Why
- Document enlargement, oedema, Descemet breaks and factors affecting tonometry.
- Interpretation and limitations
- Corneal diameter and clarity provide evidence of pressure-related stretching in infancy. Thickness affects interpretation of measured pressure, but an adult numerical correction formula is not a substitute for paediatric judgement.
- 03
Gonioscopy and anterior segment assessment - Why
- Characterise the drainage angle and associated developmental abnormalities.
- Interpretation and limitations
- The appearance helps classify the glaucoma and plan surgery. Significant corneal haze may limit direct visualisation and alter the operative approach.
- 04
Optic nerve assessment and ocular biometry - Why
- Establish structural damage and monitor abnormal globe growth.
- Interpretation and limitations
- Document the nerve, axial length and refraction over time. Age-related growth must be distinguished from excessive enlargement associated with inadequate pressure control.
- 05
Age-appropriate functional testing - Why
- Measure the child's visual development and later field function.
- Interpretation and limitations
- Use fixation or developmentally suitable acuity tests initially, adding fields and imaging when feasible. Poor acuity may reflect corneal, refractive, amblyopic or optic nerve factors together.
06Differential diagnosisRealistic alternatives and the features that help distinguish them.
Congenital tear drainage obstruction
A blocked nasolacrimal duct causes overflow and intermittent crusting, usually with a comfortable clear cornea. It does not account for pressure-related globe enlargement or Descemet breaks.
Primary corneal abnormality
Congenital corneal opacities and endothelial disorders can cause haze without the same pressure mechanism. Specialist assessment distinguishes these from glaucoma and identifies any associated anterior segment abnormalities.
Megalocornea
An enlarged clear cornea can occur without glaucoma. Pressure, optic nerve findings, ocular growth and associated anatomical features help distinguish this appearance from progressive pressure-related stretching.
Corneal infection or trauma
Keratitis or an abrasion can cause photophobia, lid spasm and tearing. Focal surface findings and the clinical history may support these alternatives, although urgent examination remains necessary.
07ManagementImmediate care, first-line treatment, alternatives and escalation.
01Suspected glaucomaArrange urgent paediatric ophthalmic assessmentFirst stepAn infant has corneal enlargement or haze with tearing, light aversion or lid spasm.+
- 1Inspect both corneas and assess visual behaviour as far as the child comfortably allows.
- 2Contact the acute eye service and describe the observed signs rather than a presumed blocked duct.
- 3Explain to the family that the pressure and drainage structures need specialist assessment.
- 4Do not require successful tonometry or a trial of antibiotic drops before making the referral.
02Confirmed primary diseaseCoordinate pressure reduction and surgical planningSpecialist assessment confirms primary congenital glaucoma and defines the affected anatomy.+
- 1Agree an individual pressure target and the urgency of intervention with the paediatric glaucoma team.
- 2Use any interim medicines only under a clear specialist plan with age-appropriate safety checks.
- 3Plan angle surgery or another procedure according to anatomy, severity and previous treatment.
- 4Arrange postoperative review and explain signs that require contact before the scheduled appointment.
03Continuing careFollow the eye and the developing visual systemInitial treatment has controlled pressure or the child is receiving ongoing glaucoma care.+
- 1Monitor pressure and structural trends to detect recurrent or insufficient control.
- 2Update refractive correction and assess whether amblyopia or squint needs additional treatment.
- 3Review medicine administration, adverse effects and practical barriers at follow-up.
- 4Maintain specialist surveillance into adulthood with a clear transfer of the treatment history.
Key medicines and prescribing safety2 treatments · regimens, roles and cautions+
Latanoprost 50 micrograms/mL eye drops — Xalatan
Specialist paediatric use follows the licensed adult schedule: one drop in each affected eye once daily, preferably in the evening; do not increase beyond once daily.Contraindicated in hypersensitivity. Evidence below one year is very limited and there are no data in preterm infants below 36 weeks gestational age. Exercise caution with uveitis, aphakia or macular oedema risk and asthma; avoid active herpetic keratitis. Explain possible permanent iris pigmentation and lash changes. Use one-minute punctal occlusion, separate other eye drops by at least five minutes, and remove contact lenses for 15 minutes. Do not combine multiple prostaglandin analogues. For patients followed into adolescence, Xalatan should not be used in pregnancy; avoid during breastfeeding or stop breastfeeding under an agreed specialist plan.
Brimonidine-containing eye drops — safety exclusion
Do not administer to neonates or infants younger than two years; no infant dose is appropriate because this age group is contraindicated.Alphagan is not recommended below 12 years and is contraindicated below two years. Serious infant reactions include somnolence, hypotonia, bradycardia and respiratory depression. Accidental administration or ingestion warrants urgent clinical assessment; check combination products as well as single-ingredient bottles.
08ComplicationsImportant consequences, why they occur and why they matter clinically.
Optic nerve damage
Progressive glaucomatous injury can permanently reduce visual function. Delayed recognition is particularly consequential because substantial structural change may occur before a child can describe visual difficulty.
Corneal scarring and astigmatism
Persistent oedema and healed Descemet breaks can leave an irregular optical surface. Even when pressure is controlled, this can reduce image quality and complicate refractive correction.
Myopia and amblyopia
Excessive eye growth can produce refractive error, while asymmetric blur disrupts visual development. These factors may contribute additional visual loss beyond damage caused directly by pressure.
Recurrent pressure elevation
Drainage resistance can persist or recur after treatment, and some children need repeated procedures or continued medicines. The risk remains relevant as the eye grows and into adult life.
09Monitoring and follow-upTreatment response, safety checks and longer-term review.
- Continue lifelong specialist follow-up, with intervals set by disease control, age, examination reliability and the postoperative plan.
- Record serial pressure, optic nerve appearance, corneal findings and eye growth rather than relying only on whether the child looks comfortable.
- Measure refraction and visual acuity at developmentally appropriate intervals and ensure prescribed glasses or amblyopia treatment remain usable.
- Ask about fatigue, wheeze, faintness, poor feeding or altered alertness when reviewing topical therapy, and assess suspected systemic adverse reactions promptly.
- Ensure families know who to contact for new corneal haze, pain, worsening vision or difficulty obtaining essential medicines.
10Special situationsVariants, exceptions and circumstances that change the usual approach.
A large eye is not simply attractive
Comments about unusually large eyes can conceal early buphthalmos. Establish whether enlargement is asymmetric, progressive or accompanied by haze and light intolerance, rather than treating the observation as cosmetic.
Corneal clarity can improve
Some oedema may clear as pressure is controlled, but residual scarring or irregular astigmatism can continue to impair the retinal image. Refractive rehabilitation remains part of treatment.
Drops act beyond the surface
Topical administration does not eliminate systemic exposure. Demonstrated punctal occlusion and avoiding excess drops help reduce exposure, but cannot make a contraindicated medicine safe for an infant.
One operation may not be enough
The need for another procedure can reflect persistent resistance or changing drainage, rather than a failure of family care. Discuss this possibility early and retain a practical follow-up plan.
11Common pitfallsFrequent interpretation and management errors.
- 01
Confusing aqueous outflow failure with obstruction of the surface tear drainage system.
- 02
Waiting for a high pressure reading in primary care before referring a symptomatic infant.
- 03
Transferring an adult glaucoma prescription to a baby without checking the exact product and age restrictions.
- 04
Assuming pressure control alone will correct amblyopia or existing optic nerve damage.
- 05
Discharging a child from surveillance because an early operation initially worked well.