Not smoking is a common suggestion in the literature. Apart from smoking cessation, there is little definitive research in this area. In addition to the selenium studies above, some recent research also is suggestive that statin use may assist.

Exophthalmos is commonly found in dogs. It is seen in brachycephalic (short-nosed) dog breeds because of the shallow orbit. However, it can lead to keratitis secondary to exposure of the cornea. Exophthalmos is commonly seen in the Pug, Boston Terrier, Pekingese, and Shih Tzu.

It is a common result of head trauma and pressure exerted on the front of the neck too hard in dogs. In cats, eye proptosis is uncommon and is often accompanied by facial fractures.

About 40% of proptosed eyes retain vision after being replaced in the orbit, but in cats very few retain vision. Replacement of the eye requires general anesthesia. The eyelids are pulled outward, and the eye is gently pushed back into place. The eyelids are sewn together in a procedure known as tarsorrhaphy for about five days to keep the eye in place. Replaced eyes have a higher rate of keratoconjunctivitis sicca and keratitis and often require lifelong treatment. If the damage is severe, the eye is removed in a relatively simple surgery known as enucleation of the eye.

The prognosis for a replaced eye is determined by the extent of damage to the cornea and sclera, the presence or absence of a pupillary light reflex, and the presence of ruptured rectus muscles. The rectus muscles normally help hold the eye in place and direct eye movement. Rupture of more than two rectus muscles usually requires the eye to be removed, because significant blood vessel and nerve damage also usually occurs. Compared to brachycephalic breeds, dochilocephalic (long-nosed) breeds usually have more trauma to the eye and its surrounding structures, so the prognosis is worse .

Graves' ophthalmopathy is diagnosed clinically by the presenting ocular signs and symptoms, but positive tests for antibodies (anti-thyroglobulin, anti-microsomal and anti-thyrotropin receptor) and abnormalities in thyroid hormones level (T3, T4, and TSH) help in supporting the diagnosis.

Orbital imaging is an interesting tool for the diagnosis of Graves' ophthalmopathy and is useful in monitoring patients for progression of the disease. It is, however, not warranted when the diagnosis can be established clinically. Ultrasonography may detect early Graves' orbitopathy in patients without clinical orbital findings. It is less reliable than the CT scan and magnetic resonance imaging (MRI), however, to assess the extraocular muscle involvement at the orbital apex, which may lead to blindness. Thus, CT scan or MRI is necessary when optic nerve involvement is suspected. On neuroimaging, the most characteristic findings are thick extraocular muscles with tendon sparing, usually bilateral, and proptosis.

Measurement of the degree of exophthalmos is performed using an exophthalmometer.

Most sources define exophthalmos/proptosis as a protrusion of the globe greater than 18 mm.

The term exophthalmos is often used when describing proptosis associated with Graves' disease.

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.

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.

Chemosis is the swelling (or edema) of the conjunctiva. It is due to the oozing of exudate from abnormally permeable capillaries. In general, chemosis is a nonspecific sign of eye irritation. The outer surface covering appears to have fluid in it. The conjunctiva becomes swollen and gelatinous in appearance. Often, the eye area swells so much that the eyes become difficult or impossible to close fully. Sometimes, it may also appear as if the eyeball has moved slightly backwards from the white part of the eye due to the fluid filled in the conjunctiva all over the eyes except the iris. The iris is not covered by this fluid and so it appears to be moved slightly inwards.

Infiltrative ophthalmopathy is found in 5-10% of patients with Graves disease and resembles exophthalmos, except that the blurry or double vision is acquired because of weakness in the ocular muscles of the eye. In addition, there is no known correlation with the patient's thyroid levels. Exophthalmos associated with Grave's disease disappears when the thyrotoxicosis is corrected. Infiltrative ophthalmopathy at times may not be cured. Treatments consist of high dose glucocorticoids and low dose radiotherapy. The current hypothesis is that infiltrative ophthalmopathy may be autoimmune in nature targeting retrobulbar tissue. Smoking may also have a causative effect.

It is usually caused by allergies or viral infections, often inciting excessive eye rubbing. Chemosis is also included in the Chandler Classification system of orbital infections.

If chemosis has occurred due to excessive rubbing of the eye, the first aid to be given is a cold water wash for eyes.

Other causes of chemosis include:

- Superior vena cava obstruction, accompanied by facial oedema

- Hyperthyroidism, associated with exophthalmos, periorbital puffiness, lid retraction, and lid lag

- Cavernous sinus thrombosis, associated with infection of the paranasal sinuses, proptosis, periorbital oedema, retinal haemorrhages, papilledema, extraocular movement abnormalities, and trigeminal nerve sensory loss

- Carotid-cavernous fistula - classic triad of chemosis, pulsatile proptosis, and ocular bruit

- Cluster headache

- Trichinellosis

- Systemic lupus erythematosus (SLE)

- Angioedema

- Acute glaucoma

- Panophthalmitis

- Orbital cellulitis

- Gonorrheal conjunctivitis

- Dacryocystitis

- Spitting cobra venom to the eye

- High concentrations of phenacyl chloride in chemical mace spray

- Urticaria

- Trauma

- Post surgical

- Rhabdomyosarcoma of the orbit

Enophthalmos is the posterior displacement of the eyeball within the orbit due to changes in the volume of the orbit (bone) relative to its contents (the eyeball and orbital fat), or loss of function of the orbitalis muscle. It should not be confused with its opposite, exophthalmos, which is the anterior displacement of the eye.

It may be a congenital anomaly, or be acquired as a result of trauma (such as in a blowout fracture of the orbit), Horner's syndrome (apparent enophthalmos due to ptosis), Marfan syndrome, Duane's syndrome, silent sinus syndrome or phthisis bulbi.

Diagnosis is done by direct observation under magnified view of slit lamp revealing the ulcer on the cornea. The use of fluorescein stain, which is taken up by exposed corneal stroma and appears green, helps in defining the margins of the corneal ulcer, and can reveal additional details of the surrounding epithelium. Herpes simplex ulcers show a typical dendritic pattern of staining. Rose-Bengal dye is also used for supra-vital staining purposes, but it may be very irritating to the eyes. In descemetoceles, the Descemet's membrane will bulge forward and after staining will appear as a dark circle with a green boundary, because it does not absorb the stain. Doing a corneal scraping and examining under the microscope with stains like Gram's and KOH preparation may reveal the bacteria and fungi respectively. Microbiological culture tests may be necessary to isolate the causative organisms for some cases. Other tests that may be necessary include a Schirmer's test for keratoconjunctivitis sicca and an analysis of facial nerve function for facial nerve paralysis.

It is often possible to diagnose myxedema on clinical grounds alone. Characteristic symptoms are weakness, cold intolerance, mental and physical slowness, dry skin, typical facies, and hoarse voice. Results of the total serum thyroxine and free thyroxine index tests usually will confirm the diagnosis.

This modality is suitable for young and pregnant people. Indications for thyroidectomy can be separated into absolute indications or relative indications. These indications aid in deciding which people would benefit most from surgery. The absolute indications are a large goiter (especially when compressing the trachea), suspicious nodules or suspected cancer (to pathologically examine the thyroid), and people with ophthalmopathy and additionally if it is the person's preferred method of treatment or if refusing to undergo radioactive iodine treatment. Pregnancy is advised to be delayed for 6 months after radioactive iodine treatment.

Both bilateral subtotal thyroidectomy and the Hartley-Dunhill procedure (hemithyroidectomy on one side and partial lobectomy on other side) are possible.

Advantages are immediate cure and potential removal of carcinoma. Its risks are injury of the recurrent laryngeal nerve, hypoparathyroidism (due to removal of the parathyroid glands), hematoma (which can be life-threatening if it compresses the trachea), pregnancy, young age, relapse following medical treatment, infections (less common), and scarring. The increase in the risk of nerve injury can be due to the increased vascularity of the thyroid parenchyma and the development of links between the thyroid capsule and the surrounding tissues. Reportedly, a 1% incidence exists of permanent recurrent laryngeal nerve paralysis after complete thyroidectomy. Removal of the gland enables complete biopsy to be performed to have definite evidence of cancer anywhere in the thyroid. (Needle biopsies are not so accurate at predicting a benign state of the thyroid). No further treatment of the thyroid is required, unless cancer is detected. Radioiodine uptake study may be done after surgery, to ensure all remaining (potentially cancerous) thyroid cells ("i.e.", near the nerves to the vocal cords) are destroyed. Besides this, the only remaining treatment will be levothyroxine, or thyroid replacement pills to be taken for the rest of the patient's life.

A 2013 review article concludes that surgery appears to be the most successful in the management of Graves' disease, with total thyroidectomy being the preferred surgical option.

Primary treatment is prompted by the administration of adequate doses of either the thyroid hormone l-throxine given intravenously or by giving L-triiodothyronine via a nasogastric tube. It is essential to identify and treat the condition precipitating the coma.

Myxedema coma is rare but often fatal. It occurs most often in elderly women and may be mistaken for one of the chronic debilitating diseases common to this age group.

Though the exact cause of myxedema is still unclear, a wealth of skillful research has demonstrated the importance of iodine. In an important study the researchers showed that in the myxedematous type of cretinism treatment with iodine normalizes thyroid function provided that the treatment is begun early in the postnatal period. If not, the prognosis remains dismal.

Mild cases are treated with lubricant eye drops or nonsteroidal anti-inflammatory drops. Severe cases threatening vision (corneal exposure or optic nerve compression) are treated with steroids or orbital decompression. In all cases, cessation of smoking is essential. Double vision can be corrected with prism glasses and surgery (the latter only when the process has been stable for a while).

Difficulty closing eyes can be treated with lubricant gel at night, or with tape on the eyes to enable full, deep sleep.

Orbital decompression can be performed to enable bulging eyes to retreat back into the head. Bone is removed from the skull behind the eyes, and space is made for the muscles and fatty tissue to fall back into the skull.

Eyelid surgery can be performed on upper and/or lower eyelids to reverse the effects of Graves' disease on the eyelids. Eyelid muscles can become tight with Graves' disease, making it impossible to close eyes all the way. Eyelid surgery involves an incision along the natural crease of the eyelid, and a scraping away of the muscle that holds the eyelid open. This makes the muscle weaker, which allows the eyelid to extend over the eyeball more effectively. Eyelid surgery helps reduce or eliminate dry eye symptoms.

For management of clinically active Graves' disease, orbitopathy (clinical activity score >2) with at least mild to moderate severity, intravenous glucocorticoids are the treatment of choice, usually administered in the form of pulse intravenous methylprednisolone. Studies have consistently shown that pulse intravenous methylprednisolone is superior to oral glucocorticoids both in terms of efficacy and decreased side effects for managing Graves' orbitopathy.

In overt primary hyperthyroidism, TSH levels are low and T and T levels are high. Subclinical hyperthyroidism is a milder form of hyperthyroidism characterized by low or undetectable serum TSH level, but with a normal serum free thyroxine level. Although the evidence for doing so is not definitive, treatment of elderly persons having subclinical hyperthyroidism could reduce the incidence of atrial fibrillation. There is also an increased risk of bone fractures (by 42%) in people with subclinical hyperthyroidism; there is insufficient evidence to say whether treatment with antithyroid medications would reduce that risk.

THS is usually diagnosed via exclusion, and as such a vast amount of laboratory tests are required to rule out other causes of the patient's symptoms. These tests include a complete blood count, thyroid function tests and serum protein electrophoresis. Studies of cerebrospinal fluid may also be beneficial in distinguishing between THS and conditions with similar signs and symptoms.

MRI scans of the brain and orbit with and without contrast, magnetic resonance angiography or digital subtraction angiography and a CT scan of the brain and orbit with and without contrast may all be useful in detecting inflammatory changes in the cavernous sinus, superior orbital fissure and/or orbital apex. Inflammatory change of the orbit on cross sectional imaging in the absence of cranial nerve palsy is described by the more benign and general nomenclature of orbital pseudotumor.

Sometimes a biopsy may need to be obtained to confirm the diagnosis, as it is useful in ruling out a neoplasm.

Differentials to consider when diagnosing THS include craniopharyngioma, migraine and meningioma.

In those without symptoms who are not pregnant there is little evidence for or against screening.

Topical antibiotics are used at hourly intervals to treat infectious corneal ulcers. Cycloplegic eye drops are applied to give rest to the eye. Pain medications are given as needed. Loose epithelium and ulcer base can be scraped off and sent for culture sensitivity studies to find out the pathogenic organism. This helps in choosing appropriate antibiotics. Complete healing takes anywhere from about a few weeks to several months.

Refractory corneal ulcers can take a long time to heal, sometimes months. In case of progressive or non-healing ulcers, surgical intervention by an ophthalmologist with corneal transplantation may be required to save the eye. In all corneal ulcers it is important to rule out predisposing factors like diabetes mellitus and immunodeficiency.

Goitre is treated according to the cause. If the thyroid gland is producing too much T3 and T4, radioactive iodine is given to the patient to shrink the gland. If goitre is caused by iodine deficiency, small doses of iodide in the form of Lugol's Iodine or KI solution are given. If the goitre is associated with an underactive thyroid, thyroid supplements are used as treatment. In extreme cases, a partial or complete thyroidectomy is required.

The prognosis of THS is usually considered good. Patients usually respond to corticosteroids, and spontaneous remission can occur, although movement of ocular muscles may remain damaged. Roughly 30–40% of patients who are treated for THS experience a relapse.

Goitre is more common among women, but this includes the many types of goitre caused by autoimmune problems, and not only those caused by simple lack of iodine.

Thin cut (2-3mm) CT scan with axial and coronal view is the optimal study of choice for orbital fractures.

Plain radiographs, on the other hand, do not sensitively capture blowout fractures. On Water's view radiograph, polypoid mass can be observed hanging from the floor into the maxillary antrum, classically known as teardrop sign, as it usually is in shape of a teardrop. This polypoid mass consists of herniated orbital contents, periorbital fat and inferior rectus muscle. The affected sinus is partially opacified on radiograph. Air-fluid level in maxillary sinus may sometimes be seen due to presence of blood. Lucency in orbits (on a radiograph) usually indicate orbital emphysema.

The best imaging modality for idiopathic orbital inflammatory disease is contrast-enhanced thin section magnetic resonance with fat suppression. The best diagnostic clue is a poorly marginated, mass-like enhancing soft tissue involving any area of the orbit.

Overall, radiographic features for idiopathic orbital inflammatory syndrome vary widely. They include inflammation of the extraocular muscles (myositis) with tendinous involvement, orbital fat stranding, lacrimal gland inflammation and enlargement (dacryoadenitis), involvement of the optic sheath complex, uvea, and sclera, a focal intraorbital mass or even diffuse orbital involvement. Bone destruction and intracranial extension is rare, but has been reported. Depending on the area of involvement, IOI may be categorized as:

- Myositic

- Lacrimal

- Anterior – Involvement of the globe, retrobulbar orbit

- Diffuse – Multifocal intraconal involvement with or without an extraconal component

- Apical – Involving the orbital apex and with intracranial involvement

Tolosa–Hunt syndrome is a variant of orbital pseudotumor in which there is extension into the cavernous sinus through the superior orbital fissure. Another disease variant is Sclerosing pseudotumor, which more often presents bilaterally and may extend into the sinuses.

CT findings

In non-enhanced CT one may observe a lacrimal, extra-ocular muscle, or other orbital mass. It may be focal or infiltrative and will have poorly circumscribed soft tissue. In contrast-enhanced CT there is moderate diffuse irregularity and enhancement of the involved structures. A dynamic CT will show an attenuation increase in the late phase, contrary to lymphoma where there is an attenuation decrease. Bone CT will rarely show bone remodeling or erosion, as mentioned above.

MR findings

On MR examination there is hypointensity in T1 weighted imaging (WI), particularly in sclerosing disease. T1WI with contrast will show moderate to marked diffuse irregularity and enhancement of involved structures. T2 weighted imaging with fat suppression will show iso- or slight hyperintensity compared to muscle. There is also decreased signal intensity compared to most orbital lesions due to cellular infiltrate and fibrosis. In chronic disease or sclerosing variant, T2WI with FS will show hypointensity (due to fibrosis). Findings on STIR (Short T1 Inversion Recovery) are similar to those on T2WI FS. In Tolosa–Hunt syndrome, findings include enhancement and fullness of the anterior cavernous sinus and superior orbital fissure in T1WI with contrast, while MRA may show narrowing of cavernous sinus internal carotid artery (ICA).

Ultrasonographic findings

On grayscale ultrasound there is reduced reflectivity, regular internal echoes, and weak attenuation, in a way, similar to lymphoproliferative lesions.

An optic nerve melanocytoma is a tumor made up of melanocytes and melanin. These tumors are typically a benign; they can grow, but rarely transform into a malignancy. Even so, local growth can affect adjacent tissues.