الفهرس 
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Abstract
Globally, childhood glaucoma accounts for around 5% of pediatric blindness. One of the most prevalent types of glaucoma in children is PCG.
The frequency of PCG is among the highest worldwide in the Middle East, and it is particularly prominent in communities with high consanguinity, particularly in cases of cousin-cousin inbreeding. In spite of this, 90% of PCG occurrences are sporadic and unrelated to any family history. Merely 10% have variable penetrance autosomal recessive inheritance.
The severity of PCG affects how the illness manifests clinically. Parents and other caregivers often notice symptoms such as tearing, rubbing of the eyes, photophobia, irritation, and shielding the eyes in sunlight. Discrepancy between the two eyes, corneal clouding, and globe enlargement may also catch their attention.
Since medical treatment is rarely effective and carries a considerable risk of side effects, surgery is the primary mode of management. Options for surgical treatment include cyclodestructive techniques, angle surgery, and filtering surgery.
Management of any secondary problems, including as amblyopia, refractive alterations, corneal clouding, and buphthalmos, should be prioritized in addition to lowering the IOP. Rather than injury to the optic nerve, amblyopia is the primary cause of blindness.
The eye’s optical system includes three major components: the cornea, the crystalline lens, and the iris. The cornea is responsible for approximately two-thirds of its optical power and aberrations, while the iris regulates pupil diameter, which determines the amount of light that enters the retina. The crystalline lens accounts for one-third of the eye’s optical power but can modify its focusing properties. Low-order and high-order ocular aberrations are the most common optical aberrations, accounting for nearly 90% of the eye’s overall wavefront aberration.
The Wavefront aberrations of the eye is not constant but changes over time, with amplitudes ranging between 0.03 and 0.5 diopters (D). Higher-order aberrations may cause a decline in contrast sensitivity, glare, starburst, and halos, which may worsen visual acuity.
Wavefront analysis is used by aberrometers to determine the eye’s refractive characteristics. Several wavefront sensing approaches have been developed for measuring wavefront errors in human eyes, such as outgoing wavefront aberrometry (e.g., Hartmann-Shack sensor), ingoing wavefront aberrometry (e.g., Tscherning aberrometer, Tracey retinal ray tracing), and double-pass aberrometry (e.g., Slit skialoscopy).
Ray Tracing (ITrace) involves a parallel laser beam traveling through the pupil, causing local aberrations that change the retina’s location. This process, which involves moving the laser beam and projecting multiple points onto the retina, results in a true wavefront error, aiding in determining forward light aberrations.
This study was designed to assess the wavefront aberrations in operated PCG cases in pediatric ophthalmology department of Alexandria Main University Hospital and compare them to age matched healthy controls using a Ray tracing technology (Itracey).