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Buphthalmos in itself is merely a clinical sign and does not generate symptoms. Patients with glaucoma often initially have no symptoms; later, they can exhibit excessive tearing (lacrimation) and extreme sensitivity to light (photophobia). On ophthalmologic exam, one can detect increased intraocular pressure, distortion of the optic disc, and corneal edema, which manifests as haziness.
Other symptoms include a prominent eyeball, Haab's striae in the Descemet's membrane of the cornea, an enlarged cornea, and myopia.
Infantile glaucoma, which often produces the clinical sign of buphthalmos, can be caused when an abnormally narrow angle between the cornea and iris blocks the outflow of aqueous humor; this causes increased intraocular pressure and eventual enlargement of the globe (eyeball). Angle closure can be caused by developmental abnormalities of the eye as well as the presence of abnormal structures within the vitreous.
The typical infant who has congenital glaucoma usually is initially referred to an ophthalmologist because of apparent corneal edema. The commonly described triad of epiphora (excessive tearing), blepharospasm and photophobia may be missed until the corneal edema becomes apparent.
Photophobia is a symptom of abnormal intolerance to visual perception of light. As a medical symptom, photophobia is not a morbid fear or phobia, but an experience of discomfort or pain to the eyes due to light exposure or by presence of actual physical sensitivity of the eyes, though the term is sometimes additionally applied to abnormal or irrational fear of light such as heliophobia. The term "photophobia" comes from the Greek φῶς ("phōs"), meaning "light", and φόβος ("phóbos"), meaning "fear". Photophobia is a common symptom of visual snow.
Patients may develop photophobia as a result of several different medical conditions, related to the eye or the nervous system. Photophobia can be caused by an increased response to light starting at any step in the visual system, such as:
- Too much light entering the eye. Too much light can enter the eye if it is damaged, such as with corneal abrasion and retinal damage, or if its pupil(s) is unable to normally constrict (seen with damage to the oculomotor nerve).
- Due to albinism, the lack of pigment in the colored part of the eyes (irises) makes them somewhat translucent. This means that the irises can't completely block light from entering the eye.
- Overstimulation of the photoreceptors in the retina
- Excessive electric impulses to the optic nerve
- Excessive response in the central nervous system
- Elevated trigeminal nerve tone (as it is sensory nerve to eye, elevated tone makes it over reactive). Elevated trigeminal tone causes elevated substance P which causes hypersensitivity. Often due to jaw misalignment.
Common causes of photophobia include migraine headaches, TMJ, cataracts, Sjogren's Syndrome, Mild Traumatic Brain Injury (MTBI), or severe ophthalmologic diseases such as uveitis or corneal abrasion. A more extensive list follows:
The diagnosis is clinical. The intraocular pressure (IOP) can be measured in the office in a conscious swaddled infant using a Tonopen or hand-held Goldmann tonometer. Usually, the IOP in normal infants is in the range of 11-14 mmHg. Buphthalmos and Haab's striae can often be seen in case of congenital glaucoma.
Aniridia is the absence of the iris, usually involving both eyes. It can be congenital or caused by a penetrant injury. Isolated aniridia is a congenital disorder which is not limited to a defect in iris development, but is a panocular condition with macular and optic nerve hypoplasia, cataract, and corneal changes. Vision may be severely compromised and the disorder is frequently associated with a number of ocular complications: nystagmus, amblyopia, buphthalmos, and cataract. Aniridia in some individuals occurs as part of a syndrome, such as WAGR syndrome (kidney nephroblastoma (Wilms tumour), genitourinary anomalies and intellectual disability), or Gillespie syndrome (cerebellar ataxia).
Aniridia may be broadly divided into hereditary and sporadic forms. Hereditary aniridia is usually transmitted in an autosomal dominant manner (each offspring has a 50% chance of being affected), although rare autosomal recessive forms (such as Gillespie syndrome) have also been reported. Sporadic aniridia mutations may affect the WT1 region adjacent to the AN2 aniridia region, causing a kidney cancer called nephroblastoma (Wilms tumor). These patients often also have genitourinary abnormalities and intellectual disability (WAGR syndrome).
Several different mutations may affect the PAX6 gene. Some mutations appear to inhibit gene function more than others, with subsequent variability in the severity of the disease. Thus, some aniridic individuals are only missing a relatively small amount of iris, do not have foveal hypoplasia, and retain relatively normal vision. Presumably, the genetic defect in these individuals causes less "heterozygous insufficiency," meaning they retain enough gene function to yield a milder phenotype.
- AN
- Aniridia and absent patella
- Aniridia, microcornea, and spontaneously reabsorbed cataract
- Aniridia, cerebellar ataxia, and mental deficiency (Gillespie syndrome)
Sturge–Weber syndrome is usually manifested at birth by a port-wine stain on the forehead and upper eyelid of one side of the face, or the whole face. The birthmark can vary in color from light pink to deep purple and is caused by an overabundance of capillaries around the ophthalmic branch of the trigeminal nerve, just under the surface of the face. There is also malformation of blood vessels in the pia mater overlying the brain on the same side of the head as the birthmark. This causes calcification of tissue and loss of nerve cells in the cerebral cortex.
Neurological symptoms include seizures that begin in infancy and may worsen with age. Convulsions usually happen on the side of the body opposite the birthmark which vary in severity. There may also be muscle weakness on the side of the body opposite the birthmark.
Some children will have developmental delays and cognitive delays; about 50% will have glaucoma (optic neuropathy often associated with increased intraocular pressure), which can be present at birth or develop later. Glaucoma can be expressed as leukocoria, which should include also further evaluation for retinoblastoma. Increased pressure within the eye can cause the eyeball to enlarge and bulge out of its socket (buphthalmos).
Sturge–Weber syndrome rarely affects other body organs.
Sturge–Weber syndrome or Sturge–Weber–Krabbe disease, sometimes referred to as encephalotrigeminal angiomatosis, is a rare congenital neurological and skin disorder. It is one of the phakomatoses and is often associated with port-wine stains of the face, glaucoma, seizures, mental retardation, and ipsilateral leptomeningeal angioma (cerebral malformations and tumors). Sturge Weber Syndrome can be classified into three different types. Type 1 includes facial and leptomeningeal angiomas as well as the possibility of glaucoma or choroidal lesions. Normally, only one side of the brain is affected. This type is the most common. Type 2 involvement includes a facial angioma (port wine stain) with a possibility of glaucoma developing. There is not any evidence of brain involvement. Symptoms can show at any time beyond the initial diagnosis of the facial angioma. The symptoms can include glaucoma, cerebral blood flow abnormalities and headaches. More research is needed on this type of Sturge Weber Syndrome. Type 3 has leptomeningeal angioma involvement exclusively. The facial angioma is absent and glaucoma rarely occurs. This type is only diagnosed via brain scan.
Sturge-Weber is an embryonal developmental anomaly resulting from errors in mesodermal and ectodermal development. Unlike other neurocutaneous disorders (phakomatoses), Sturge-Weber occurs sporadically (i.e., does not have a hereditary cause). It is caused by a somatic activating mutation occurring in the GNAQ gene. Radiological findings will show tram track calcifications on CT, bilaterally.