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.

In an eye with iridocyclitis, (inflammation of both the iris and ciliary body), the involved pupil will be smaller than the uninvolved, due to reflex muscle spasm of the sphincter muscle of the iris.

Generally, conjunctivitis does not affect the pupils.

With acute angle-closure glaucoma, the pupil is generally fixed in mid-position, oval, and responds sluggishly to light, if at all.

Shallow anterior chamber depth may indicate a predisposition to one form of glaucoma (narrow angle) but requires slit-lamp examination or other special techniques to determine it.

In the presence of a "red eye", a shallow anterior chamber may indicate acute glaucoma, which requires immediate attention.

A physician often can diagnose ichthyosis by looking at the skin. A family history is very useful. In some cases, a skin biopsy is done to help to confirm the diagnosis. In some instances, genetic testing may be helpful in making a diagnosis. Diabetes has not been definitively linked to acquired ichthyosis or ichthyosis vulgaris; however, there are case reports associating new onset ichthyosis with diabetes.

Ichthyosis has been found to be more common in Native American, Asian, Mongolian groups. There is no way to prevent ichthyosis.

Ichthyosis is a genetically and phenotypically heterogeneous disease that can be isolated and restricted to the skin manifestations or associated with extracutaneous symptoms. One of which is limb reduction defect known as CHILD syndrome; a rare inborn error of metabolism of cholesterol biosynthesis that is usually restricted to one side of the body. A research done in Egypt proved that it is not a child syndrome and discussed all the case report.

Diagnosis can be established on clinical grounds and this may be enhanced with studies on surgically excised corneal tissue and in some cases with molecular genetic analyses. As clinical manifestations widely vary with the different entities, corneal dystrophies should be suspected when corneal transparency is lost or corneal opacities occur spontaneously, particularly in both corneas, and especially in the presence of a positive family history or in the offspring of consanguineous parents.

Superficial corneal dystrophies - "Meesmann dystrophy" is characterized by distinct tiny bubble-like, punctate opacities that form in the central corneal epithelium and to a lesser extent in the peripheral cornea of both eyes during infancy that persists throughout life. Symmetrical reticular opacities form in the superficial central cornea of both eyes at about 4–5 years of age in "Reis-Bücklers corneal dystrophy". Patient remains asymptomatic until epithelial erosions precipitate acute episodes of ocular hyperemia, pain, and photophobia. Visual acuity eventually becomes reduced during the second and third decades of life following a progressive superficial haze and an irregular corneal surface. In "Thiel–Behnke dystrophy", sub-epithelial corneal opacities form a honeycomb-shaped pattern in the superficial cornea. Multiple prominent gelatinous mulberry-shaped nodules form beneath the corneal epithelium during the first decade of life in "Gelatinous drop-like corneal dystrophy" which cause photophobia, tearing, corneal foreign body sensation and severe progressive loss of vision. "Lisch epithelial corneal dystrophy" is characterized by feather shaped opacities and microcysts in the corneal epithelium that are arranged in a band-shaped and sometimes whorled pattern. Painless blurred vision sometimes begins after sixty years of life.

Corneal stromal dystrophies - "Macular corneal dystrophy" is manifested by a progressive dense cloudiness of the entire corneal stroma that usually first appears during adolescence and eventually causing severe visual impairment. In "Granular corneal dystrophy" multiple small white discrete irregular spots that resemble bread crumbs or snowflakes become apparent beneath Bowman zone in the superficial central corneal stroma. They initially appear within the first decade of life. Visual acuity is more or less normal. "Lattice dystrophy" starts as fine branching linear opacities in Bowman's layer in the central area and spreads to the preiphery. Recurrent corneal erosions may occur. The hallmark of "Schnyder corneal dystrophy" is the accumulation of crystals within the corneal stroma which cause corneal clouding typically in a ring-shaped fashion.

Posterior corneal dystrophies - "Fuchs corneal dystrophy" presents during the fifth or sixth decade of life. The characteristic clinical findings are excrescences on a thickened Descemet membrane (cornea guttae), generalized corneal edema and decreased visual acuity. In advanced cases, abnormalities are found in the all layers of the cornea. In "posterior polymorphous corneal dystrophy" small vesicles appear at the level of Descemet membrane. Most patients remain asymptomatic and corneal edema is usually absent. "Congenital hereditary endothelial corneal dystrophy" is characterized by a diffuse ground-glass appearance of both corneas and markedly thickened (2–3 times thicker than normal) corneas from birth or infancy.

The diagnosis of harlequin-type ichthyosis relies on both physical examination and certain laboratory tests.

Physical assessment at birth is vital for the initial diagnosis of harlequin ichthyosis. Physical examination reveals characteristic symptoms of the condition especially the abnormalities in the skin surface of newborns. Abnormal findings in physical assessments usually result in employing other diagnostic tests to ascertain the diagnosis.

Genetic testing is the most specific diagnostic test for harlequin ichthyosis. This test reveals a loss of function mutation on the ABCA12 gene. This gene is important in the regulation of protein synthesis for the development of the skin layer. Mutations in the gene may cause impaired transport of lipids in the skin layer and may also lead to shrunken versions of the proteins responsible for skin development. Less severe mutations result in a collodion membrane and congenital ichthyosiform erythroderma-like presentation. ABCA12 is an ATP binding cassette (ABC) transporter, and is a member of a large family of proteins that hydrolyze ATP to transport cargo across membranes. ABCA12 is thought to be a lipid transporter in keratinocytes necessary for lipid transport into lamellar granules during the formation of the lipid barrier.

Biopsy of skin may be done to assess the histologic characteristics of the cells. Histological findings usually reveal hyperkeratotic skin cells, which leads to a thick, white and hard skin layer.

Diagnosis commonly occurs later in childhood and often occurs incidentally in asymptomatic patients or as a cause of visual impairment. The first symptoms are commonly found during routine vision screenings.

A number of examinations can be used to determine the extent of the syndrome and its severity. Fluorescein angiography is quite useful in diagnosing the disease, and the use of ultrasonography and optical coherence tomography (OCT) are helpful in confirming the disease. Neuro-ophthalmic examinations reveal pupillary defects (see Marcus Gunn Pupil). Funduscopic examinations, examinations of the fundus of the eye, allow detection of arteriovenous malformations. Neurological examinations can determine hemiparesis and paresthesias. Malformations in arteriovenous connections and irregular functions in the veins may be distinguished by fluorescein angiographies. Cerebral angiography examinations may expose AVMs in the cerebrum. MRIs are also used in imaging the brain and can allow visualization of the optic nerve and any possible atrophy. MRI, CT, and cerebral angiography are all useful for investigating the extent and location of any vascular lesions that are affecting the brain. This is helpful in determining the extent of the syndrome.

Treatment of lagopthalmos can include both supportive care methods as well as surgical. If unable to receive surgery, artificial tears should be administered at least four times a day to the cornea to preserve the tear film. Leading up to a surgery, a patient can undergo a tarsorrhaphy which partially sews the eye shut temporarily to further protect the cornea as the patient waits for care. Multiple surgical treatments exist for Lagopthalmos but the most prevalent method includes weighing the upper eyelid down by surgically inserting a gold plate. Due to possible complications in conjunction with both the upper and lower eyelid, it might also be required to undergo a second surgery to tighten and elevate the lower eyelid to ensure both the upper and lower eyelids can fully close and protect the cornea.

Early stages may be asymptomatic and may not require any intervention. Initial treatment may include hypertonic eyedrops and ointment to reduce the corneal edema and may offer symptomatic improvement prior to surgical intervention.

Suboptimal vision caused by corneal dystrophy usually requires surgical intervention in the form of corneal transplantation. Penetrating keratoplasty, a common type of corneal transplantation, is commonly performed for extensive corneal dystrophy.

With penetrating keratoplasty (corneal transplant), the long-term results are good to excellent. Recent surgical improvements have been made which have increased the success rate for this procedure. However, recurrence of the disease in the donor graft may happen. Superficial corneal dystrophies do not need a penetrating keratoplasty as the deeper corneal tissue is unaffected, therefore a lamellar keratoplasty may be used instead.

Phototherapeutic keratectomy (PTK) can be used to excise or ablate the abnormal corneal tissue. Patients with superficial corneal opacities are suitable candidates for a this procedure.

Diagnosing SS is complicated by the range of symptoms a patient may manifest, and the similarity between symptoms of SS and those of other conditions. Also, patients who have symptoms of SS approach different specialities regarding their symptoms which make the diagnosis difficult. Since the symptoms of this autoimmune disorder such as dry eyes and dry mouth are very common among people, and mostly observed from the age of 40 and above, it is often mistaken as age-related, thus ignored. However, some medications can also cause symptoms that are similar to those of SS. The combination of several tests, which can be done in a series, can eventually lead to the diagnosis of SS.

SS is usually classified as either 'primary' or 'secondary'. Primary Sjögren syndrome occurs by itself and secondary Sjögren syndrome occurs when another connective tissue disease is present.

Blood tests can be done to determine if a patient has high levels of antibodies that are indicative of the condition, such as antinuclear antibody (ANA) and rheumatoid factor (because SS frequently occurs secondary to rheumatoid arthritis), which are associated with autoimmune diseases. Typical SS ANA patterns are SSA/Ro and SSB/La, of which Anti-SSB/La is far more specific; Anti-SSA/Ro is associated with numerous other autoimmune conditions, but are often present in SS. However, Anti-SSA and Anti-SSB tests are frequently not positive in SS.

The rose bengal test uses a stain that measures state and function of the lacrimal glands. This test involves placing the non-toxic dye rose bengal on the eyes. The dye’s distinctive colour helps in determining the state and functioning of tear film and the rate of tear evaporation. Any distinctive colour change observed will be indicative of SS, but many related diagnostic tools will be used to confirm the condition of SS.

Schirmer's test measures the production of tears: a strip of filter paper is held inside the lower eyelid for five minutes, and its wetness is then measured with a ruler. Producing less than of liquid is usually indicative of SS. This measurement analysis varies among people depending on other eye-related conditions and medications in use when the test is taken. A slit-lamp examination can reveal dryness on the surface of the eye.

Symptoms of dry mouth and dryness in the oral cavity are caused by the reduced production of saliva from the salivary glands (parotid gland, submandibular gland, and sublingual gland). To check the status of salivary glands and the production of saliva, a salivary flow-rate test is performed, in which the person is asked to spit as much as they can into a cup, and the resulting saliva sample is collected and weighed. This test's results can determine whether the salivary glands are functioning adequately. Not enough saliva produced could mean the person has SS. An alternative test is non-stimulated whole saliva flow collection, in which the person spits into a test tube every minute for 15 minutes. A resultant collection of less than is considered a positive result.

A lip/salivary gland biopsy takes a tissue sample that can reveal lymphocytes clustered around salivary glands, and damage to these glands due to inflammation. This test involves removing a sample of tissue from a person’s inner lip/salivary gland and examining it under a microscope. In addition, a sialogram, a special X-ray test, is performed to see if any blockage is present in the salivary gland ducts (i.e. parotid duct) and the amount of saliva that flows into the mouth.

Also, a radiological procedure is available as a reliable and accurate test for SS. A contrast agent is injected into the parotid duct, which opens from the cheek into the vestibule of the mouth opposite the neck of the upper second molar tooth. Histopathology studies should show focal lymphocytic sialadenitis. Objective evidence of salivary gland involvement is tested through ultrasound examinations, the level of unstimulated whole salivary flow, a parotid sialography or salivary scintigraphy, and autoantibodies against Ro (SSA) and/or La (SSB) antigens.

SS can be excluded from people with past head and neck radiation therapy, acquired immunodeficiency syndrome (AIDS), pre-existing lymphoma, sarcoidosis, graft-versus-host disease, and use of anticholinergic drugs.

Nocturnal lagophthalmos is the inability to close the eyelids during sleep. It may reduce the quality of sleep, cause exposure-related symptoms or, if severe, cause corneal damage (exposure keratopathy). The degree of lagophthalmos can be minor (obscure lagophthalmos), or quite obvious.

It is often caused by an anomaly of the eyelid that prevents full closure. Treatment may involve surgery to correct the malposition of the eyelid(s). Punctal plugs may be used to increase the amount of lubrication on the surface of the eyeball by blocking some of the tear drainage ducts. Eye drops may also be used to provide additional lubrication or encourage the eyes to increase tear production.

The condition is not widely understood; in at least one instance a passenger was removed from a US Airways flight because of it.

Treatments for ichthyosis often take the form of topical application of creams and emollient oils, in an attempt to hydrate the skin. Creams containing lactic acid have been shown to work exceptionally well in some cases. Application of propylene glycol is another treatment method. Retinoids are used for some conditions.

Exposure to sunlight may improve or worsen the condition. In some cases, excess dead skin sloughs off much better from wet tanned skin after bathing or a swim, although the dry skin might be preferable to the damaging effects of sun exposure.

There can be ocular manifestations of ichthyosis, such as corneal and ocular surface diseases. Vascularizing keratitis, which is more commonly found in congenital keratitis-ichythosis-deafness (KID), may worsen with isotretinoin therapy.

There is no specific pathological testing or technique available for the diagnosis of the disease, although the International Study Group criteria for the disease are highly sensitive and specific, involving clinical criteria and a pathergy test. Behçet's disease has a high degree of resemblance to diseases that cause mucocutaneous lesions such as "Herpes simplex" labialis, and therefore clinical suspicion should be maintained until all the common causes of oral lesions are ruled out from the differential diagnosis.

Visual acuity, or color vision loss with concurrent mucocutaneous lesions or systemic Behçet's disease symptoms should raise suspicion of optic nerve involvement in Behçet's disease and prompt a work-up for Behçet's disease if not previously diagnosed in addition to an ocular work-up. Diagnosis of Behçet's disease is based on clinical findings including oral and genital ulcers, skin lesions such as erythema nodosum, acne, or folliculitis, ocular inflammatory findings and a pathergy reaction. Inflammatory markers such ESR, and CRP may be elevated. A complete ophthalmic examination may include a slit lamp examination, optical coherence tomography to detect nerve loss, visual field examinations, fundoscopic examination to assess optic disc atrophy and retinal disease, fundoscopic angiography, and visual evoked potentials, which may demonstrate increased latency. Optic nerve enhancement may be identified on Magnetic Resonance Imaging (MRI) in some patients with acute optic neuropathy. However, a normal study does not rule out optic neuropathy. Cerebrospinal fluid (CSF) analysis may demonstrate elevated protein level with or without pleocytosis. Imaging including angiography may be indicated to identify dural venous sinus thrombosis as a cause of intracranial hypertension and optic atrophy.

Mild forms of IBS should be diagnosable from appearance and patient history alone. Severe cases of IBS are hard to distinguish from mild EHK.

A skin biopsy shows a characteristic damaged layer in the upper spinous level of the skin. Again it may be difficult to distinguish from EHK.

The gene causing IBS is known and so a definite diagnosis can be given by genetic testing.

Overheating: The scaling of the skin prevents normal sweating so hot weather and/or vigorous exercise can cause problems.

Eye problems: The eyelids can be pulled down by the tightness of the skin and this can make eyelids (but usually just the lower one) very red and they are prone to drying and irritation.

Constriction bands: Very rarely children with this condition can have tight bands of skin around their fingers or toes (usually at the tips) that can prevent proper blood circulation to the area.

Hair loss: Severe scaling of the skin on the scalp can lead to patchy loss of hair, but this is rarely permanent.

There is no prevention mechanism for SS due to its complexity as an autoimmune disorder. However, lifestyle changes can reduce the risk factors of getting SS or reduce the severity of the condition with patients who have already been diagnosed. Diet is strongly associated with inflammation that is mostly seen in many autoimmune related diseases including SS. An experimental study concludes that SS patients show high sensitivity to gluten that directly relates to inflammation. Moderate exercise is also found to be helpful in SS patients mainly reducing the effect of lung inflammation.

Constant care is required to moisturise and protect the skin. The hard outer layer eventually peels off, leaving the vulnerable inner layers of the dermis exposed. Early complications result from infection due to fissuring of the hyperkeratotic plates and respiratory distress due to physical restriction of chest wall expansion.

Management includes supportive care and treatment of hyperkeratosis and skin barrier dysfunction. A humidified incubator is generally used. Intubation is often required until nares are patent. Nutritional support with tube feeds is essential until eclabium resolves and infants can begin nursing. Ophthalmology consultation is useful for the early management of ectropion, which is initially pronounced and resolves as scale is shed. Liberal application of petrolatum is needed multiple times a day. In addition, careful debridement of constrictive bands of hyperkeratosis should be performed to avoid digital ischemia. Cases of digital autoamputation or necrosis have been reported due to cutaneous constriction bands. Relaxation incisions have been used to prevent this morbid complication.

In the past, the disorder was nearly always fatal, whether due to dehydration, infection (sepsis), restricted breathing due to the plating, or other related causes. The most common cause of death was systemic infection and sufferers rarely survived for more than a few days. However, improved neonatal intensive care and early treatment with oral retinoids, such as the drug Isotretinoin (Isotrex), may improve survival. Early oral retinoid therapy has been shown to soften scales and encourage desquamation. After as little as two weeks of daily oral isotretinoin, fissures in the skin can heal, and plate-like scales can nearly resolve. Improvement in the eclabium and ectropion can also be seen in a matter of weeks. Children who survive the neonatal period usually evolve to a less severe phenotype, resembling a severe congenital ichthyosiform erythroderma. Patients continue to suffer from temperature dysregulation and may have heat and cold intolerance. Patients can also have generalized poor hair growth, scarring alopecia, contractures of digits, arthralgias, failure to thrive, hypothyroidism, and short stature. Some patients develop a rheumatoid factor-positive polyarthritis. Survivors can also develop fish-like scales and retention of a waxy, yellowish material in seborrheic areas, with ear adhered to the scalp.

The oldest known survivor is Nusrit "Nelly" Shaheen, who was born in 1984 and is in relatively good health as of April 2016. Lifespan limitations have not yet been determined with the new treatments.

A study published in 2011 in the Archives of Dermatology concluded, "Harlequin ichthyosis should be regarded as a severe chronic disease that is not invariably fatal. With improved neonatal care and probably the early introduction of oral retinoids, the number of survivors is increasing."

Keratitis–ichthyosis–deafness syndrome (also known as "Erythrokeratodermia progressiva Burns," "Ichthyosiform erythroderma, corneal involvement, and deafness," and "KID syndrome,") presents at birth/infancy and is characterized by pregressive corneal opacification, either mild generalized hyperkeratosis or discrete erythematous plaques, and neurosensory deafness.

It is caused by a mutation in connexin 26.

The diagnostic work up usually includes and MRI of the brain, an EEG, ophthalmic examination and a cardiac ECHO.

Muscle biopsy - which is not commonly done - may show storage of abnormal material and secondary mitochondrial abnormalities in skeletal muscle. Other features that may be seen on muscle biopsy include variability in fibre size, increase in internal and centralized nuclei, type 1 fibre hypotrophy with normally sized type 2 fibres, increased glycogen storage and variable vacuoles on light microscopy

The diagnosis is confirmed by sequencing of the EPG5.

Diagnosis is based on appearance and family history. KID syndrome or keratosis follicularis spinulosa decalvans have some similar symptoms and must be eliminated.

This includes Ataxia-telegiectasia, Chédiak-Higashi syndrome, DiGeorge syndrome, Griscelli syndrome and Marinesco-Sjogren syndrome.

Intraocular lymphoma is a rare malignant form of eye cancer. Intraocular lymphoma may affect the eye secondarily from a metastasis from a non-ocular tumor or may arise within the eye primarily (primary intraocular lymphoma, PIOL). PIOL is a subset of primary central nervous system lymphoma (PCNSL). PCNSL (and PIOL) are most commonly a diffuse large B-cell immunohistologic subtype of non-Hodgkin's lymphoma according to the World Health Organization (WHO) classification of lymphomas. The most common symptoms of PIOL include blurred or decreased vision due to tumor cells in the vitreous. Most cases of PIOL eventuate to central nervous system involvement (PCNSL) while only 20% of PCNSL lead to intraocular (PIOL) involvement. PIOL and PCNSL remain enigmas because both structures are immunologically privileged sites (the brain sits behind the blood–brain barrier and the retina sits behind the blood-retinal barrier) and so do not normally have immune cells trafficking through these structures. What is more, while the vast majority of PCNSL in patients with acquired immune deficiency syndrome (AIDS) is related to the Epstein-Barr virus (EBV), the development of PCNSL and PIOL in immunocompetent patients is unknown and shows no general relation to infectious DNAs.

In immunocompetent patients, PIOL most commonly affects patients in their fifties and sixties. AIDS patients typically develop the disease earlier in their lives.

PIOL affects the sub-retinal pigment epithelium (RPE), can invade into the retina, the vitreous, and the optic nerve. Ophthalmoscopy frequently reveals creamy yellow-to-orange colored subretinal infiltrates. Fluorescein angiography may reveal "leopard spot" patterns due to sub-RPE infiltrates that stain early and progressively or mottling of the RPE due to hyper- and hypofluorescent window defects.

PIOL is known as a masquerade syndrome because it frequently simulates the signs and symptoms of uveitis. As such, PIOL is frequently treated with corticosteroids. Occasionally, PIOL has mimicked a retinitis and has been treated with antiviral medication. It is not until the supposed uveitis fails to respond to treatment, becomes recalcitrant to treatment, or shows worsening with discontinuation of corticosteroid treatment that another cause is sought out. If PIOL is suspected, it is important to first obtain a magnetic resonance image (MRI) of the brain to rule out cerebral involvement (PCNSL). If MRI is negative, lumbar puncture with cerebrospinal fluid (CSF) cytology should be performed to further rule out CNS disease. Histopathologic identification of atypical lymphocytes is considered the gold standard for diagnosing PCNSL/PIOL. If CSF cytology is negative or inconclusive and PIOL is suspected, a vitrectomy is often performed with cytologic analysis. Furthermore, adjunctive testing including polymerase chain reaction (PCR) amplification to identify monoclonal rearrangements of the immunoglobulin heavy chain (IgH) gene (for B-cell lymphomas) or T-cell receptor (TCR, for the very rare T-cell lymphomas) can be performed.

Previously, radiation therapy was the mainstay treatment for PCNSL/PIOL, but methotrexate has now become first-line.

According to the International Study Group guidelines, for a patient to be diagnosed with Behçet's disease, the patient must have oral (aphthous) ulcers (any shape, size, or number at least 3 times in any 12 months period) along with 2 out of the following 4 "hallmark" symptoms:

- eye inflammation (iritis, uveitis, retinal vasculitis, cells in the vitreous)

- genital ulcers (including anal ulcers and spots in the genital region and swollen testicles or epididymitis in men)

- pathergy reaction (papule >2 mm dia. 24–48 hrs or more after needle-prick). The pathergy test has a specificity of 95 percent to 100 percent, but the results are often negative in American and European patients

- skin lesions (papulo-pustules, folliculitis, erythema nodosum, acne in post-adolescents not on corticosteroids)

Despite the inclusive criteria set forth by the International Study Group, there are cases where not all the criteria can be met and therefore a diagnosis cannot readily be made. There is however a set of clinical findings that a physician can rely upon in making a tentative diagnosis of the disease; essentially Behçet's disease does not always follow the International Study Group guidelines and so a high degree of suspicion for a patient who presents having any number of the following findings is necessary:

- arthritis/arthralgia

- cardio-vascular problems of an inflammatory origin

- changes of , psychoses

- deep vein thrombosis

- epididymitis

- extreme exhaustion

- inflammatory problems in chest and lungs

- mouth ulcers

- nervous system symptoms

- problems with hearing or balance

- stomach or bowel inflammation

- superficial thrombophlebitis

- any other members of the family with a diagnosis of Behçet's disease.

As with all types of ichthyosis, there is no cure but the symptoms can be relieved.

- Moisturizers

- Prevention of overheating

- Eye drops (to prevent the eyes from becoming dried out)

- Systemic Retinoids (isotretinoin and acitretin are very effective, but careful monitoring for toxicity is required. Only severe cases may require intermittent therapy.)

Psychological therapy or support may be required as well.

The only treatment for MWS is only symptomatic, with multidisciplinary management

The symptoms would appear at birth or shortly after birth. The combination of physical symptoms on the child would suggest they have CHILD syndrome. A skin sample examined under a microscope would suggest the characteristics of the syndrome and an X-Ray of the trunk, arms, and legs would help to detect underdeveloped bones. A CT scan would help detect problems of the internal organs.