The orbit refers to the bony walls surrounding the cavity in which the eye is located, as well as all the structures surrounding the eyeball within these walls (the muscles that move the eye, the lacrimal gland, the optic nerve, and the fat tissues that encircle these structures).
Benign or malignant masses that develop from any of the structures forming the orbit are called orbital tumors. Tumors may also develop from adjacent tissues (such as eyelids, sinuses, or the brain) and extend into the orbit, as well as metastatic orbital tumors that spread from other areas of the body.
Orbital tumors/masses may include:
Diseases that show a mass effect similar to orbital tumors include:
Most orbital tumors in childhood are benign developmental anomalies. The most common among them are dermoid cysts (well-defined masses containing skin elements) and capillary hemangiomas (vascular anomalies, such as birthmarks).
Capillary hemangiomas, while they may regress and disappear by age seven, are masses that can grow during the first two years, potentially causing permanent amblyopia (lazy eye) if they cover the visual axis. When they do not cover the visual axis, they can be monitored closely for spontaneous resolution, but if they obstruct vision, they require immediate treatment. The most effective and side-effect-free treatment today is beta-blocker therapy administered as oral drops.
Orbital cellulitis, which commonly spreads from neighboring sinuses, can cause tumor-like growths in children. This is an emergency condition and requires quick diagnosis and treatment with appropriate antibiotics.
Malignant orbital tumors are less common in children, but can include orbital rhabdomyosarcoma, a fast-growing tumor that typically occurs in children around 7-8 years old. Additionally, metastatic neuroblastoma from adrenal glands may present with bruises around the eyes, making the child appear battered. Immediate ophthalmologic evaluation is crucial to make the diagnosis and initiate treatment.
The most common benign tumors in the adult orbit are related to abnormal growth of blood vessels. The most frequently seen is cavernous hemangioma, a low-flow, low-pressure vascular mass. Structures that include not only blood vessels but also lymphatic vessels are referred to as lymphangiomas or, more commonly now, orbital venolymphatic malformations. These masses can rapidly grow during infections, possibly turning into large chocolate cysts with internal bleeding.
Another group of tumors in adults is those originating from the lacrimal gland(tear gland), often seen after the age of 40. These tumors can be either benign or malignant. Benign types include dacryoadenitis (inflammation of the gland),dacryops (cyst formed due to blockage of tear ducts),lymphoma, and pleomorphic adenomas. Although pleomorphic adenomas are benign, they can become malignant if not completely removed during surgery. The most common malignant tumors in this category are adenoid cystic carcinomas, painful tumors that invade surrounding bone and can spread to other organs, requiring extensive surgical removal followed by radiation therapy and chemotherapy.
Another category includes neurogenic (nerve tissue-originating) tumors such as gliomas and meningiomas from the optic nerve, and schwannomas and neurofibromas from peripheral nerves.
A common condition that can be confused with orbital tumors, especially those associated with thyroid disease (Graves),is idiopathic orbital inflammation syndrome. It can present in various forms, often with painful swelling and a false tumor appearance. Some forms are confined to the lacrimal gland or the muscles that move the eye. This condition may be associated with rheumatological diseases or systemic syndromes, and resolution occurs when the underlying disease is treated. Therefore, rheumatological consultation is necessary. When no underlying disease is found, this syndrome is referred to as idiopathic, and it may recur with stress. Treatment includes steroids and immunomodulators.
The most common malignant primary orbital tumor in adults is lymphoma. Treatment involves chemotherapy and radiation, based on the biopsy results and the specific lymphoma type, and requires oncology consultation.
Another common condition is metastatic tumors that spread to the orbit from other organ systems, such as lung, breast, and prostate cancers. These tumors may be detected first in the orbit, and their treatment requires addressing the primary cancer.
Among rare orbital tumors, the solitary fibrous tumor (also called hemangiopericytoma) is noteworthy. It exhibits interesting characteristics and can behave either benignly or malignantly. If not completely removed during surgery, it may become more aggressive. Therefore, careful imaging and a well-planned surgical approach are essential.
Orbital tumors are often discovered incidentally, without any symptoms. They may be detected during imaging studies, such as a CT scan or MRI, which are requested for unrelated complaints or after facial trauma or a headache. In some cases, tumors are detected when patients experience asymmetry in the eyes, bulging, displacement of the eyeball, visual disturbances, or double vision due to limited eye movement.
Some common orbital tumors are completely benign and can be monitored for life without growing. However, some benign orbital tumors can grow at certain stages and exert pressure on the optic nerve, potentially threatening vision.
Malignant orbital tumors are dangerous because they can grow, press on eye tissues, damage vision, and spread to the brain or other parts of the body, threatening life.
Whether benign or malignant, large tumors that cause severe bulging of the eye can lead to serious complications such as corneal erosion, infections, and even perforation, resulting in vision loss if left untreated or delayed.
Therefore, the danger of an orbital tumor depends on its structure, size, location, and whether or not it is treated.
Orbital tumors can cause a variety of symptoms, depending on the type of tumor. Some tumors, like hemangiomas, may never cause symptoms throughout life. Benign tumors, such as dermoid cysts, may remain the same size for a long time and suddenly grow. If these tumors are disrupted by trauma, they can cause severe redness, swelling, and tissue deformities.
Apart from certain malignant lacrimal gland tumors and idiopathic orbital inflammation (also known as false tumors),orbital tumors typically do not cause pain. Sometimes, pressure on the nerves may cause headaches or discomfort in the orbit. Tumors that press on the circulation system may cause visible redness in the eye due to twisted or thickened blood vessels.
Some orbital tumors appear suddenly, while others grow gradually. In growing orbital tumors, the eyeball may bulge forward, causing the eyelids to open. Some tumors may push the eye in different directions or affect the muscles and nerves, causing the eye to deviate and resulting in double vision. Tumors that press on the levator muscle, which lifts the upper eyelid, may lead to eyelid drooping as the first sign.
Tumors directly affecting the optic nerve or indirectly pressing on it may cause periodic vision loss, visual field problems, or permanent vision loss. Changes in the pupil’s response to light can assist in diagnosing these cases.
Orbital tumors can be primary tumors originating from the tear glands, bones, nerves, muscles, or lymphatic tissues within the orbit, or they may spread to the orbit from neighboring tissues. Additionally, tumors can spread to the orbit as metastases from tumors in other parts of the body. Inflammation or infection can also lead to masses in the orbit.
The treatment plan for orbital tumors is evaluated based on the mass’s structure, size, and characteristics.
Benign tumors that do not threaten vision may be monitored without intervention through examination and imaging methods. In cases of tumors related to infection/inflammation, treating the underlying cause is usually sufficient. This may involve medical treatments such as antibiotics, steroids, and immunomodulators, or injections into the orbit. If an abscess is present or if these masses cause significant pressure leading to vision loss, emergency orbitotomy and surgical intervention will be necessary.
Cavernous hemangiomas that grow and begin to show symptoms are removed via orbital surgery. Some recommend early removal of even silent hemangiomas while they are still small. Benign masses like dermoids, which have the potential to rupture due to growth or trauma, should be surgically removed intact once diagnosed.
For tumors with an unclear structural character, diagnostic measures may include fine-needle aspiration biopsy, incisional biopsy through orbitotomy, or full or near-complete removal of the mass via orbital surgery, depending on the findings from clinical examination and imaging results. The tissue sample is then sent to pathology, and further treatments are planned based on the results.
The diagnosis of malignant orbital tumors is made after the surgical removal and pathological examination of the tissue. Once diagnosed, necessary treatments are determined, with oncology involved for further therapies such as radiotherapy and chemotherapy.
For example, the most common malignant tumor in childhood, rhabdomyosarcoma, is treated with chemotherapy and additional radiotherapy following a large biopsy to evaluate its histological structure. These tumors, which have indistinct boundaries and may leave microscopic remnants in the orbit despite seeming completely removed, typically require chemotherapy as the primary treatment because complete surgical removal is not always effective in these cancers. Some studies even suggest that leaving a relatively larger tumor behind may enhance the effectiveness of chemotherapy.
Similarly, for lymphoma, the most common malignant tumor in adults, the definitive diagnosis is made via a tissue sample obtained through surgery and subtyping. Afterward, any remaining mass is treated with appropriate chemotherapy and radiotherapy protocols. In most of these cases, because the treatment after surgery often requires additional therapies, aggressive surgery attempting to remove the entire mass, which might risk damaging critical orbital tissues, is avoided.
In some tumors, complete removal of the mass can be curative, but in the cases mentioned, including certain cancers, only the minimum necessary amount of tissue is removed during surgery, as the aim is to obtain a tissue sample for diagnosis and to alleviate the pressure caused by the growing mass.
In contrast, some cancers, such as pleomorphic adenomas of the lacrimal gland and solitary fibrous tumors, should be completely removed, as leaving part of the mass behind would increase the tumor’s aggressiveness. These tumors are well-defined, and full removal is crucial.
It should be remembered that in aggressive and malignant tumors, the priority is to preserve the patient's life and, if possible, their vision function. Sometimes, due to life-threatening circumstances, it may be necessary to sacrifice vision or other functions of the eye. When the risk to life is lower, decisions might need to be made between preserving vision function and aesthetic considerations, based on the tumor's type, size, and location. All these situations, along with the goal of the surgery, should be thoroughly discussed with the patient and their family prior to the procedure.
Because the orbit is a deep and enclosed space containing complex and critical anatomical structures such as nerves, blood vessels, and muscles, surgeries in this area require significant experience and should only be undertaken after extensive training in oculoplastic, orbital, and reconstructive surgery, often under the guidance of a mentor for many years.
A successful orbital tumor surgery requires detailed examination, in-depth knowledge of orbital anatomy, and careful evaluation of preoperative orbital imaging such as CT or MRI scans. Additionally, it is essential to use the technique that allows for the gentlest manipulation of tissues while providing the widest visual field during the surgery.
There are several defined surgical techniques for approaching the orbit. The best technique for the patient should be selected based on the tumor's location and size, as well as minimizing surgical damage and ensuring the least cosmetic impact, such as minimizing visible scars. Orbital access can be through cosmetic incisions on the upper or lower eyelids, or, in some cases, the tumor can be accessed without any external incision, entering through the inner eyelid or the surface of the eyeball.
In cases where the tumor is located in a deep part of the orbit near the brain, an endoscopic approach or access through the scalp to lift the skull bone over the eyeball can be used. Today, highly experienced surgeons use minimally invasive techniques, which involve the smallest and most hidden incisions and cause the least tissue damage, thereby minimizing risks to critical orbital structures.
Orbital tumor surgery can be performed under local anesthesia with or without sedation, or general anesthesia is often preferred, where the patient is fully asleep and their blood pressure can be controlled. In most cases, the patient is discharged after 24 hours of observation.
The goal of orbital tumor surgery is to remove the tumor without damaging vision or the muscles and nerves that control the eyeball. In benign tumors, preserving tissue and function is the priority, while in malignant tumors, the focus may be on saving life or critical vision, potentially at the cost of other functions. Before surgery, the goals and potential risks/benefits should be carefully reviewed between the doctor and the patient.
Depending on the type of surgery, varying degrees of swelling and bruising may occur, but these are generally not long-lasting. Closing the eyelid is usually unnecessary, and vision function is often monitored in the first 24 hours. Most patients can resume normal activities soon after surgery. After the first 24 hours of close monitoring, a follow-up visit is scheduled during the first week to remove sutures, and rapid recovery is typically observed at this stage.
In cases where the tumor is completely removed or there is no risk of recurrence, any tissue void left behind is filled first with edema fluid, and soon after, soft tissue regenerates to fill the space, leaving no noticeable difference in appearance between the two eyes.
After orbital surgery, the patient typically spends the first 24 hours in the hospital to monitor for risks of nerve compression due to bleeding. Visual function, light reactions, and eye movements are assessed frequently, especially within the first two hours. Mild pain or discomfort may be treated with pain relievers, and intravenous treatment may be provided for nausea or vomiting, which should be prevented to avoid increasing bleeding.
Because the orbit is a closed system, the most important concern after surgery is pressure on the optic nerve due to bleeding. Activities that could increase the risk of bleeding, such as bending forward, lifting heavy objects, straining, or using blood thinners, should be avoided in the early stages. Swimming, using pools, exercises that require straining, and contact sports will be prohibited for up to 3 weeks. The surgical area should not be exposed to water for 3-4 days to avoid infection.
Depending on the surgeon's preferences, ice application in the first 2-3 days and short-term steroid use may be recommended to reduce swelling. A superficial antibiotic ointment on the surgical site may be used for up to one week, and systemic antibiotics may be necessary in some cases.
Orbital tumors fall under the specialized field of oculoplastic surgery, but performing surgery in this anatomical area requires advanced training. Historically, in times when it was difficult to reach an oculoplastic surgeon, brain surgeons approached orbital tumors by lifting the skull.
This complicated approach, which inevitably damages most critical orbital structures, is only used for large tumors that have spread to the brain or for tumors located in the orbital apex, where it is too risky to approach via the orbital route. For other orbital tumors, it is essential to find an experienced oculoplastic/orbital surgeon who can remove the tumor using a minimally invasive, front-facing approach.
In cases with widespread tumors or involvement of structures outside the orbit, a multidisciplinary team including neurosurgeons, maxillofacial surgeons, and ENT specialists may be involved. Depending on the pathology results, additional treatments should be coordinated with the radiation oncology/medical oncology departments during the postoperative period.