What is the orbit and why is it important?

The orbit (eye socket) is the bony cavity bounded by the bones of the face and skull, containing the eyeball, muscles responsible for eye movement, optic nerves, vessels and connective tissue. There are 2 of them, one on each side of the nose. In an adult individual, its volume is 30 cc on average and the eyeball occupies an area of 7 cc on average. In addition to containing the structures necessary for visual function, the orbit is a very important area due to its close neighborhood with the cerebral cavity above, the cerebrospinal fluid at the back and the sinuses that play a role in breathing on the sides.

What are orbital diseases?

Diseases affecting the tissues in the orbit are called “orbital diseases”. These diseases can be grouped as inflammatory, space-occupying, structural, vascular or functional diseases according to their clinical effects. Also they can be grouped according to the causes as congenital orbital disorders, inflammatory orbital diseases, orbital tumors and malformations and trauma-related orbital disorders.

What are the symptoms of orbital diseases?

The orbital cavity is surrounded by bone tissues. Therefore, a sudden increase in volume (edema, bleeding, inflammatory reactions) or space-occupying lesions (mass, abscess, hematoma, etc.) in the orbit causes compression, displacement or loss of function of other tissues.

Structural and functional changes are also seen in the affected tissues.

Forward displacement of the eye (proptosis), prominent veins, pain behind the eye, vision loss, impaired color vision, narrowing of the visual field, decreased and/or painful eye movements, double vision and newly developed strabismus are warning signs that should be investigated for orbital disease.

Fracture and displacement of surrounding bone tissues may develop after trauma. As a result, intra-orbital structures and the eyeball may be displaced downward (hypoglobus) or inward (enophthalmos). Compression of extraocular muscles and connective tissue at the fracture site causes strabismus, limitation of eye movements, pain and double vision.

What are congenital orbital disorders?

Congenital orbital disorders include developmental disorders and tumors of the eyeball and surrounding tissues. Undevelopment (anophthalmos) or underdevelopment (microphthalmos) of the eyeball is often associated with impaired development of the surrounding orbital tissue.

At or before birth, in cases where the eye is absent, underdevelopment or asymmetry of the orbit and the affected facial half may be noticed, and if there are accompanying neurological developmental disorders or syndromes, their symptoms may be detected. Especially in the presence of unilateral anophthalmos/microphthalmos, early volume-forming treatments should be initiated to ensure orbital development and prevent facial asymmetry in the future.

Developmental disorders of the bones of the head and face (craniosynostosis, congenital clefts such as meningocele/encephalocele) and some syndromes (Goldenhar Syndrome, Treacher Collins Syndrome) can affect the bony framework that forms the orbit and lead to congenital orbital disorders.

The most common congenital orbital tumors are dermoid and epidermoid cysts, which are often located at the tip of the eyebrow, grow very slowly, and are recognized as soft and painless swelling. A congenital tumor called dermolipoma is selected as a lipoma on the eyeball and may contain fine hairs.

Teratoma, on the other hand, is recognized at birth as prominence in one eye (proptosis). Tumors such as hamartoma and choristoma can also be seen. Although congenital orbital tumors are often benign, they can affect the development of the orbit and face, the position of the eye and the optic nerve in infancy, so they should be diagnosed early and an appropriate follow-up interval should be determined.

What are inflammatory diseases of the orbit?

Inflammatory diseases of the orbit cause edema of the tissues in the orbit due to infectious or non-infectious (inflammatory) causes, increase in volume, compression of some tissues and consequently structural-functional changes. Symptoms such as prominence, pain behind the eye and double vision may be observed.

Infectious diseases often require close follow-up and hospitalization and medical/surgical treatment to preserve vision and prevent spread to the brain and meninges. The most common non-infectious cause is eye involvement due to thyroid disease. Inflammatory diseases of the orbit can also be seen in some rheumatic diseases.

Pseudotumor orbit (idiopathic orbital inflammation syndrome)

It is a disease whose clinical findings and radiological images resemble orbital tumors but develops due to an inflammatory reaction without a tumor. It may cause thickening of the extraocular muscles, enlargement of the lacrimal gland or the appearance of an indistinct mass in the orbit.

What are trauma-related orbital disorders?

Damage to the orbit can occur due to blunt or sharp trauma. Examples of blunt orbital trauma include traffic accidents, falling from a height, being hit in the eye by a fist or a soccer ball. In blunt traumas, fracture of the orbital bone walls and bleeding in the orbit are frequently seen.

Orbital fractures require treatment if they cause double vision, restriction of eye movements, collapse of the eye, multiple fractures and severe aesthetic defects. Sharp traumas are orbital injuries caused by a piercing object such as a knife, firearm, piece of iron or pen.

In addition to damage to the eyeball, orbital fracture, bleeding or foreign body in the orbit may be seen. In all orbital traumas, it is of great importance to be examined by an experienced oculoplastic surgeon after the vital functions are taken under control and to perform emergency interventions if necessary in order to preserve vision.

What is an orbital tumor?

Orbital tumors are tumors that originate from structures in the eye socket. Orbital tumors can be benign or malignant tumors. Since there are important structures related to the eye and vision in this region, even if the tumor is benign, it can have detrimental effects on vision.

What are the types of orbital tumors?

Tumors originating from the muscles, nerves, vascular structures, lacrimal gland, connective tissue and surrounding bony tissue in the orbit can be seen (primary orbital tumors). Tumors originating from the structures located around the orbit such as brain/brain membrane tumors, sinus tumors, eyelid and eyeball tumors can also spread to the orbit (secondary orbital tumors).

Tumor cells can also spread to the orbit in diseases such as leukemia, lung cancer, breast cancer and prostate cancer (metastatic orbital tumors).

What are the symptoms of orbital tumors?

The first symptom that occurs in orbital tumors is that the mass pushes the eye and surrounding structures out of the anterior opening with its space-occupying effect and the eye protrudes forward (proptosis).

Depending on the location of the tumor, the eyeball may be pushed lower or higher than the other eye. Pushing the fatty tissue in the orbit forward may cause swelling of the lids and under the eyebrows.

In addition, the optic nerve may be damaged and structural and functional losses may develop due to the mass and the surrounding reaction or due to the tension caused by the eye being pushed forward. Clinical manifestations include decreased/loss of vision in the affected eye, visual field obscuration and impairment of color vision.

Tumors originating from or compressing the muscles that move the eye affect muscle function. Eye movements and vision with both eyes depend on the coordination of the muscles in both eyes, and tumor-induced involvement of any muscle leads to disruption of this coordination. Restricted eye movements, strabismus and double vision may develop.

Compression of the veins in the orbit causes the normally unnoticeable capillaries on the surface of the eyeball to enlarge and become prominent, causing a redness in the eye. In addition, vascular tumors can also extend to the lids and thin red-purple veins can be seen under the skin of the lids when viewed from the outside.

Facial asymmetry may be seen in tumors originating from the bony tissue surrounding the orbit. Blurred vision, double vision or headache may occur due to the mass effect. In tumors affecting the lacrimal gland, a feeling of dryness in the eye may develop and the outer part of the upper lid may droop downwards (it takes the shape of a horizontal letter S). Blockage of the duct involved in tear absorption due to tumors causes watery eyes. Some childhood tumors progress very slowly and may be asymptomatic for a long period of time. On the other hand, some tumors may cause sudden bruising around the eye.

What are the symptoms of orbital tumors?

The first symptom that occurs in orbital tumors is that the mass pushes the eye and surrounding structures out of the anterior opening with its space-occupying effect and the eye protrudes forward (proptosis).

Depending on the location of the tumor, the eyeball may be pushed lower or higher than the other eye. Pushing the fatty tissue in the orbit forward may cause swelling of the lids and under the eyebrows.

In addition, the optic nerve may be damaged and structural and functional losses may develop due to the mass and the surrounding reaction or due to the tension caused by the eye being pushed forward. Clinical manifestations include decreased/loss of vision in the affected eye, visual field obscuration and impairment of color vision.

Tumors originating from or compressing the muscles that move the eye affect muscle function. Eye movements and vision with both eyes depend on the coordination of the muscles in both eyes, and tumor-induced involvement of any muscle leads to disruption of this coordination. Restricted eye movements, strabismus and double vision may develop.

Compression of the veins in the orbit causes the normally unnoticeable capillaries on the surface of the eyeball to enlarge and become prominent, causing a redness in the eye. In addition, vascular tumors can also extend to the lids and thin red-purple veins can be seen under the skin of the lids when viewed from the outside.

Facial asymmetry may be seen in tumors originating from the bony tissue surrounding the orbit. Blurred vision, double vision or headache may occur due to the mass effect. In tumors affecting the lacrimal gland, a feeling of dryness in the eye may develop and the outer part of the upper lid may droop downwards (it takes the shape of a horizontal letter S). Blockage of the duct involved in tear absorption due to tumors causes watery eyes. Some childhood tumors progress very slowly and may be asymptomatic for a long period of time. On the other hand, some tumors may cause sudden bruising around the eye.

Causes of orbital tumors?

Orbital tumors can originate from all tissues in this area, or they can spread from cancers located in neighboring structures or distant body parts. Tumors originating from the muscles, nerves, vascular structures, lacrimal gland, connective tissue and surrounding bony tissue in the orbit are called primary orbital tumors.

Spread of the tumors to the orbit from structures located around the orbit (brain/membrane tumors, sinus tumors, eyelid and eyeball tumors) causes secondary orbital tumors. In addition, the spread of tumor cells to the orbit in diseases such as leukemia, lung cancer, breast cancer and prostate cancer can lead to metastatic orbital tumors.

Primary orbital tumors

Primary orbital tumors refer to tumors originating primarily from orbital tissues. The orbit contains extraocular muscles, nerves, vascular structures, lacrimal gland and connective tissue. Capillary hemangioma, cavernous hemangioma, and lymphangioma are tumors originating from vascular structures.

Optic nerve glioma, neurofibroma, meningioma and schwannoma arise from nerve tissue or nerve sheaths. Benign tumors such as fibrous histiocytoma, solitary fibrous tumor, fibrous dysplasia, osteoma or malignant tumors such as rhabdomyosarcoma, osteosarcoma, chondrosarcoma, fibrosarcoma can be seen in orbital muscle, cartilage, bone and connective tissue. The main lacrimal gland primary tumors are adenoid cystic carcinoma and malignant mixed tumor, most commonly pleomorphic adenoma.

Secondary orbital tumors

Secondary tumors are seen when tumors originating from the eyeball, eyelids, tear ducts, sinuses and brain spread to the orbit. The most common eyeball tumor that spreads to the orbit is retinoblastoma in children and choroidal malignant melanoma in adults. Spread to the orbit is more risky in tumors located in the eyelids, especially near the root of the nose.

Metastatic orbital tumors

It is the spread of tumor cells from another cancer site in the body to the orbit, often through the blood. All internal organ, blood and skin tumors can spread to the orbit. In children, orbital metastasis is most commonly seen due to leukemia, lymphoma and neuroblastoma. In orbital metastases due to leukemia, ocular metastasis often develops before the diagnosis of leukemia and the first finding is prominence in one or both eyes. In neuroblastoma, orbital metastasis is seen in the advanced stages of the disease. Bruising develops around both eyes and may be confused with trauma.

Orbital metastases are most commonly seen in adults due to lung, breast and prostate cancer. While the diagnosis of cancer is known in 75% of patients, orbital findings may be the first harbinger of cancer in 25%. Due to its excessive blood supply, metastasis develops most frequently to the muscles responsible for eye movement and associated symptoms are observed. Individuals with known cancer or a history of cancer should be examined for orbital metastasis in the presence of pain behind the eye, prominence of the eye and restriction in eye movement.

How are orbital tumors treated?

First of all, it should be determined whether the tumor is benign or malignant. In some tumors, clinical and/or radiological findings are typical and treatment planning can be started without the need for pathological diagnosis.

In a group of patients, a biopsy is performed for diagnostic purposes and the tumor type is determined by histopathological examination. The main treatment for malignant primary orbital tumors is surgery, and the surgical plan is determined according to the location and type of the tumor.

Surgical treatment may be required for tumors that compress the optic nerve, threaten vision, cause significant displacement of the eye or double vision, even if they are benign. Chemotherapy and/or radiotherapy may provide more effective treatment, especially in some childhood orbital tumors and metastatic tumors.

In the treatment of secondary orbital tumors, although removal of the mass extending to the orbit may provide relief of eye symptoms, evaluation with other related specialities and, if necessary, simultaneous surgery is often planned.