Laboratory Studies
Aniridia: Chromosome analysis and genetic counseling are important parts of the workup.
Axenfeld-Rieger syndrome: Patients may need workup for associated systemic abnormalities.
Many other systemic anomaly – associated glaucoma conditions require appropriate workup including genetic analysis, laboratory studies, and imaging to diagnose and manage the patient's systemic diseases.
Imaging Studies
Neurofibromatosis
The most serious complication of neurofibromatosis type 1 (NF-1) is optic nerve and/or chiasm glioma (in 15% of patients).
An MRI of the orbit and brain is needed to screen for the tumor.
Sturge-Weber syndrome
In Sturge-Weber syndrome, calcium deposits located predominantly in the occipital lobe of the brain parenchyma can be detected by a CT scan. These deposits follow the cerebral convolutions and give the appearance of a railroad track.
Angiomatous malformations, decreased cerebral volume, and increased choroidal plexus volume are the other findings of Sturge-Weber syndrome. An MRI can delineate these findings better than a CT scan.
Other Tests
Peters anomaly
B-scan is needed to evaluate intraocular structures that are obstructed by the corneal opacity.
Electrophysiologic tests occasionally are needed to evaluate the visual potential of the eye prior to making decision on intervention.
Nanophthalmos
Pachymetry, A- and B-scan ultrasonography, and ultrasound biomicroscopy (UBM) are useful in helping to establish a diagnosis.
All glaucoma types
Pachymetry readings are important in all types of glaucoma, including childhood glaucoma, to adjust for IOP readings.
In a small study, the mean central corneal thickness of children with different types of childhood glaucoma was measured. According to this study, in 34 children with glaucoma, IOP was overestimated by 3 mm Hg or more in 41.2% of them. In children with Sturge-Weber syndrome, the mean central corneal thickness was 591.9 +/- 23.1 µm, and, in children with aniridia, the mean central corneal thickness was 754.5 +/- 92.6 µm. [7]
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Axenfeld-Rieger syndrome with iris atrophy, corectopia, and pseudopolycoria.
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Female patient with plexiform neurofibroma (NF-1). Upper right eyelid involvement, associated with ipsilateral buphthalmos. In Image A (left), patient is aged 8 months; in Image B (right), patient is aged 8 years.
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Female infant with Sturge-Weber syndrome. Facial port-wine nevus involves the left eyelid, associated with ipsilateral buphthalmos.
