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Penetrating karatoplasty and endothelial keratoplasty can be used as treatments for severe cases of ICE [2,8]. Because glaucoma and elevated intraocular pressure are often present in ICE patients, long term follow up may be needed to ensure adequate intraocular pressures are maintained [2,7]
Since the condition appears to slowly subside or diminish on its own, there are no specific treatments for this condition available.
Some precautions include regular visits to an ophthalmologist or optometrist and general testing of the pupil and internal eye through fundamental examinations (listed below). The examinations can determine if any of the muscles of the eye or retina, which is linked to the pupil, have any problems that could relate to the tadpole pupil condition.
Corneal and Retinal Topography: computerized tests that maps the surface of the retina, or the curvature of the cornea.
Fluorescein Angiogram: evaluation of blood circulation in the retina.
Dilated Pupillary Exam: special drops expand the pupil, which then allows doctors to examine the retina.
Slit-Lamp Exam: By shining a small beam of light in the eye, eye doctors can diagnose cataracts, glaucoma, retinal detachment, macular degeneration, injuries to the cornea, and dry eye disease.
Ultrasound: Provides a picture of the eye’s internal structure, and can evaluate ocular tumors, or the retina if its suffering from cataracts or hemorrhages.
Plateau iris is a medical condition of the eye resulting from pushing of peripheral part of iris forward, by the large or anteriorly placed ciliary body causing angle closer glaucoma.
http://image.slidesharecdn.com/gonioscopy-140211072931-phpapp01/95/gonioscopy-70-638.jpg?cb=1392103893
this configuration is usually corrected by iridectomy.
if the glaucoma persists even after iridectomy then it is called plateau iris syndrome, this is managed by miotics or laser peripheral iridoplasty
PEX is usually diagnosed by an eye doctor who examines the eye using a microscope. The method is termed slit lamp examination and it is done with an "85% sensitivity rate and a 100% specificity rate." Since the symptom of increased pressure within the eye is generally painless until the condition becomes rather advanced, it is possible for people afflicted with glaucoma to be in danger yet not be aware of it. As a result, it is recommended that persons have regular eye examinations to have their levels of intraocular pressure measured, so that treatments can be prescribed before there is any serious damage to the optic nerve and subsequent loss of vision.
The United States Preventive Services Task Force as of 2013 states there is insufficient evidence to recommend for or against screening for glaucoma. Therefore, there is no national screening program in the US. Screening, however, is recommended starting at age 40 by the American Academy of Ophthalmology.
There is a glaucoma screening program in the UK. Those at risk are advised to have a dilated eye examination at least once a year.
Diagnosis is made by an ophthalmologist or optometrist based on the clinical presentation. One indication can be the Amsler sign, which is the presence of blood (hyphema) in the aspirated vitreous fluid, in paracentesis of the anterior chamber. This is caused due to iris atrophy usually seen in FHI and exposure of the fragile iris vasculature to the vitreous fluid. The sudden change of pressure in the anterior chamber upon suction induced by the paracentesis, or during a cataract surgery, causes bursting of the fragile superficial iris capillaries resultsing in micro-bleeding. This is one clinical diagnostic sign of FHI slit lamp examination shows stringy keratic precipitates
Patients usually do not require treatment due to benign nature of the disease. In case cataract develops patients generally do well with cataract surgery.
The disease is chronic and often progresses slowly. Prognosis is generally poor when associated with glaucoma [1,2].
Molecular (DNA) testing for PAX6 gene mutations (by sequencing of the entire coding region and deletion/duplication analysis) is available for isolated aniridia and the Gillespie syndrome. For the WAGR syndrome, high-resolution cytogenetic analysis and fluorescence in situ hybridization (FISH) can be utilized to identify deletions within chromosome band 11p13, where both the PAX6 and WT1 genes are located.
On photographs taken using a flash, instead of the familiar red-eye effect, leukocoria can cause a bright white reflection in an affected eye. Leukocoria may appear also in low indirect light, similar to eyeshine.
Leukocoria can be detected by a routine eye exam (see Ophthalmoscopy). For screening purposes, the red reflex test is used. In this test, when a light is shone briefly through the pupil, an orange red reflection is normal. A white reflection is leukocoria.
Norrie disease and other NDP related diseases are diagnosed with the combination of clinical findings and molecular genetic testing. Molecular genetic testing identifies the mutations that cause the disease in about 85% of affected males. Clinical diagnoses rely on ocular findings. Norrie disease is diagnosed when grayish-yellow fibrovascular masses are found behind the eye from birth through three months. Doctors also look for progression of the disease from three months through 8–10 years of age. Some of these progressions include cataracts, iris atrophy, shallowing of anterior chamber, and shrinking of the globe. By this point, people with the condition either have only light perception or no vision at all.
Molecular genetic testing is used for more than an initial diagnosis. It is used to confirm diagnostic testing, for carrier testing females, prenatal diagnosis, and preimplantation genetic diagnosis. There are three types of clinical molecular genetic testing. In approximately 85% of males, mis-sense and splice mutations of the NDP gene and partial or whole gene deletions are detected using sequence analysis. Deletion/duplication analysis can be used to detect the 15% of mutations that are submicroscopic deletions. This is also used when testing for carrier females. The last testing used is linkage analysis, which is used when the first two are unavailable. Linkage analysis is also recommended for those families who have more than one member affected by the disease.
On MRI the retinal dysplasia that occurs with the syndrome can be indistinguishable from persistent hyperplastic primary vitreous, or the dysplasia of trisomy 13 and Walker–Warburg syndrome.
If caught early, the neovascularization can be reversed with prompt pan retinal photocoagulation (PRP), or injection of anti-VEGF medications with subsequent PRP. The injection blocks the direct effect of VEGF and acts more quickly but will wear off in about 6 weeks. PRP has a slower onset of action but can last permanently. Once the neovascularization has been longstanding, the new vessels recruit fibrous tissue, and as this forms and contracts, the angle can be permanently damaged, and will not respond to treatment. If this occurs, then surgical intervention is required to reduce the pressure (such as a glaucoma drainage implant)
Screening for glaucoma is usually performed as part of a standard eye examination performed by optometrists and ophthalmologists. Testing for glaucoma should include measurements of the intraocular pressure via tonometry, anterior chamber angle examination or gonioscopy, and examination of the optic nerve to look for any visible damage to it, or change in the cup-to-disc ratio and also rim appearance and vascular change. A formal visual field test should be performed. The retinal nerve fiber layer can be assessed with imaging techniques such as optical coherence tomography, scanning laser polarimetry, and/or scanning laser ophthalmoscopy (Heidelberg retinal tomogram).
Owing to the sensitivity of all methods of tonometry to corneal thickness, methods such as Goldmann tonometry should be augmented with pachymetry to measure the central corneal thickness (CCT). A thicker-than-average cornea can result in a pressure reading higher than the 'true' pressure whereas a thinner-than-average cornea can produce a pressure reading lower than the 'true' pressure.
Because pressure measurement error can be caused by more than just CCT (i.e., corneal hydration, elastic properties, etc.), it is impossible to 'adjust' pressure measurements based only on CCT measurements. The frequency doubling illusion can also be used to detect glaucoma with the use of a frequency doubling technology perimeter.
Examination for glaucoma also could be assessed with more attention given to sex, race, history of drug use, refraction, inheritance and family history.
Glaucoma has been classified into specific types:
This condition is often associated with diabetes in advanced proliferative diabetic retinopathy. Other conditions causing rubeosis iridis include central retinal vein occlusion, ocular ischemic syndrome, and chronic retinal detachment.
Despite the temporary nature of the vision loss, those experiencing amaurosis fugax are usually advised to consult a physician immediately as it is a symptom that may herald serious vascular events, including stroke. Restated, “because of the brief interval between the transient event and a stroke or blindness from temporal arteritis, the workup for transient monocular blindness should be undertaken without delay.” If the patient has no history of giant cell arteritis, the probability of vision preservation is high; however, the chance of a stroke reaches that for a hemispheric TIA. Therefore, investigation of cardiac disease is justified.
A diagnostic evaluation should begin with the patient's history, followed by a physical exam, with particular importance being paid to the ophthalmic examination with regards to signs of ocular ischemia. When investigating amaurosis fugax, an ophthalmologic consult is absolutely warranted if available. Several concomitant laboratory tests should also be ordered to investigate some of the more common, systemic causes listed above, including a complete blood count, erythrocyte sedimentation rate, lipid panel, and blood glucose level. If a particular cause is suspected based on the history and physical, additional relevant labs should be ordered.
If laboratory tests are abnormal, a systemic disease process is likely, and, if the ophthalmologic examination is abnormal, ocular disease is likely. However, in the event that both of these routes of investigation yield normal findings or an inadequate explanation, noninvasive duplex ultrasound studies are recommended to identify carotid artery disease. Most episodes of amaurosis fugax are the result of stenosis of the ipsilateral carotid artery. With that being the case, researchers investigated how best to evaluate these episodes of vision loss, and concluded that for patients ranging from 36–74 years old, "...carotid artery duplex scanning should be performed...as this investigation is more likely to provide useful information than an extensive cardiac screening (ECG, Holter 24-hour monitoring, and precordial echocardiography)." Additionally, concomitant head CT or MRI imaging is also recommended to investigate the presence of a “clinically silent cerebral embolism.”
If the results of the ultrasound and intracranial imaging are normal, “renewed diagnostic efforts may be made,” during which fluorescein angiography is an appropriate consideration. However, carotid angiography is not advisable in the presence of a normal ultrasound and CT.
The pressure within the eye is maintained by the balance between the fluid that enters the eye through the ciliary body and the fluid that exits the eye through the trabecular meshwork.
It is important to differentiate CPEO from other pathologies that may cause an ophthalmoplegia. There are specific therapies used for these pathologies.
CPEO is diagnosed via muscle biopsy. On examination of muscle fibers stained with Gömöri trichrome stain, one can see an accumulation of enlarged mitochondria. This produces a dark red staining of the muscle fibers given the name “ragged red fibers”. While ragged red fibers are seen in normal aging, amounts in excess of normal aging give a diagnosis of a mitochondrial myopathy.
Polymerase Chain Reaction (PCR), from a sample of blood or muscle tissue can determine a mutation of the mtDNA.
Elevated acetylcholine receptor antibody level which is typically seen in myasthenia gravis has been seen in certain patients of mitochondrial associated ophthalmoplegia.
It is important to have a dilated eye exam to determine if there is pigmentary retinopathy that may signify Kearns-Sayre syndrome which is associated with cardiac abnormalities.
MRI may be helpful in the diagnosis, in one study volumes of medial rectus, lateral rectus, and inferior rectus muscles in CPEO were not smaller than normal (in contrast to the profound atrophy typical of neurogenic paralysis). Although volumes of the superior rectus muscle-levator complex and superior oblique were significantly reduced.
Scientists are studying different populations and relationships to try to learn more about the disease. They have found associations with different groups but it is not yet clear what the underlying factors are and how they affect different peoples around the world.
- Glaucoma patients. While PEX and glaucoma are believed to be related, there are cases of persons with PEX without glaucoma, and persons with glaucoma without PEX. Generally, a person with PEX is considered as having a risk of developing glaucoma, and vice versa. One study suggested that the PEX was present in 12% of glaucoma patients. Another found that PEX was present in 6% of an "open-angle glaucoma" group. Pseudoexfoliation syndrome is considered to be the most common of identifiable causes of glaucoma. If PEX is diagnosed without glaucoma, there is a high risk of a patient subsequently developing glaucoma.
- Country and region. Prevalence of PEX varies by geography. In Europe, differing levels of PEX were found; 5% in England, 6% in Norway, 4% in Germany, 1% in Greece, and 6% in France. One contrary report suggested that levels of PEX were higher among Greek people. One study of a county in Minnesota found that the prevalence of PEX was 25.9 cases per 100,000 people. It is reportedly high in northern European countries such as Norway, Sweden and Finland, as well as among the Sami people of northern Europe, and high among Arabic populations, but relatively rare among African Americans and Eskimos. In southern Africa, prevalence was found to be 19% of patients in a glaucoma clinic attending to persons of the Bantu tribes.
- Race. It varies considerably according to race.
- Gender. It affects women more than men. One report was that women were three times more likely than men to develop PEX.
- Age. Older persons are more likely to develop PEX. And persons younger than 50 are highly unlikely to have PEX. A study in Norway found that the prevalence of PEX of persons aged 50–59 was 0.4% while it was 7.9% for persons aged 80–89 years. If a person is going to develop PEX, the average age in which this will happen is between 69 and 75 years, according to the Norwegian study. A second corroborating report suggested that it happens primarily to people 70 and older. While older people are more likely to develop PEX, it is not seen as a "normal" part of aging.
- Other diseases. Sometimes PEX is associated with the development of medical problems other than merely glaucoma. There are conflicting reports about whether PEX is associated with problems of the heart or brain; one study suggested no correlations while other studies found statistical links with Alzheimer's disease, senile dementia, cerebral atrophy, chronic cerebral ischemia, stroke, transient ischemic attacks, heart disease, and hearing loss.
Quick determination of the cause may lead to urgent measures to save the eye and life of the patient. High clinical suspicion should be kept for painless vision loss in patients with atherosclerosis, deep venous thrombosis, atrial fibrillation, pulmonary thromboembolism or other previous embolic episodes. Those caused by a carotid artery embolism or occlusion have the potential for further stroke by detachment of embolus and migration to an end-artery of the brain. Hence, proper steps to prevent such an eventuality need to be taken.
Retinal arterial occlusion is an ophthalmic emergency, and prompt treatment is essential. Completely anoxic retina in animal models causes irreversible damage in about 90 minutes. Nonspecific methods to increase blood flow and dislodge emboli include digital massage, 500 mg IV acetazolamide and 100 mg IV methylprednisolone (for possible arteritis). Additional measures include paracentesis of aqueous humor to decrease IOP acutely. An ESR should be drawn to detect possible giant cell arteritis. Improvement can be determined by visual acuity, visual field testing, and by ophthalmoscopic examination.
At a later stage, pan-retinal photocoagulation (PRP) with an argon laser appears effective in reducing the neovascular components and their sequelae.
The visual prognosis for ocular ischemic syndrome varies from usually poor to fair, depending on speed and effectiveness of the intervention. However, prompt diagnosis is crucial as the condition may be a presenting sign of serious cerebrovascular and ischemic heart diseases.
In 2009, the Undersea and Hyperbaric Medical Society added "central retinal artery occlusion" to their list of approved indications for hyperbaric oxygen (HBO). When used as an adjunctive therapy, the edema reducing properties of HBO, along with down regulation of inflammatory cytokines may contribute to the improvement in vision. Prevention of vision loss requires that certain conditions be met: the treatment be started before irreversible damage has occurred (over 24 hours), the occlusion must not also occur at the ophthalmic artery, and treatment must continue until the inner layers of the retina are again oxygenated by the retinal arteries.
Typically a coloboma appears oval or comet shaped with round end towards the centre. There may be a few vessels (retinal or choroidal) at the edges. The surface may have irregular depression.
Ocular hypertension is treated with either medications or laser. Medications that lower intraocular pressure work by decreasing aqueous humor production and/or increasing aqueous humor outflow. Laser trabeculoplasty works by increasing outflow. The cannabinoids found in cannabis sativa and indica (marijuana) have been shown to reduce intraocular pressure, by up to 50% for approximately four to five hours. But due to the duration of effect, significant side-effect profile, and lack of research proving efficacy, the American Glaucoma Society issued a position statement in 2009 regarding the use of marijuana as a treatment for glaucoma.
Persistent tunica vasculosa lentis is a congenital ocular anomaly. It is a form of persistent hyperplastic primary vitreous (PHPV).
It is a developmental disorder of the vitreous. It is usually unilateral and first noticed in the neonatal period. It may be associated with micropthalmos, cataracts, and increased intraocular pressure. Elongated ciliary processes are visible through the dilated pupil. A USG B-scan confirms diagnosis in the presence of a cataract.
If the diagnostic workup reveals a systemic disease process, directed therapies to treat that underlying cause should be initiated. If the amaurosis fugax is caused by an atherosclerotic lesion, aspirin is indicated, and a carotid endarterectomy considered based on the location and grade of the stenosis. Generally, if the carotid artery is still patent, the greater the stenosis, the greater the indication for endarterectomy. "Amaurosis fugax appears to be a particularly favorable indication for carotid endarterectomy. Left untreated, this event carries a high risk of stroke; after carotid endarterectomy, which has a low operative risk, there is a very low postoperative stroke rate." However, the rate of subsequent stroke after amaurosis is significantly less than after a hemispheric TIA, therefore there remains debate as to the precise indications for which a carotid endarterectomy should be performed. If the full diagnostic workup is completely normal, patient observation is recommended.
Intraocular pressure should be measured as part of the routine eye examination.
It is usually only elevated by iridocyclitis or acute-closure glaucoma, but not by relatively benign conditions.
In iritis and traumatic perforating ocular injuries, the intraocular pressure is usually low.