Orbital decompression is an operation to make more room inside the eye socket. The eye socket is called the “orbit.” It is a cone-shaped space made of bone and filled with the eyeball, eye muscles, nerves, fat, and blood vessels. Sometimes the tissues inside the orbit become swollen, enlarged, or crowded. When that happens, pressure builds up. The eye can bulge forward, the eyelids may not close, the cornea can dry out, the eye muscles can become tight, and the optic nerve can be squeezed. If the optic nerve is squeezed, vision can be lost. Orbital decompression reduces that pressure. A surgeon does this by removing small, carefully chosen sections of the bony walls, removing some orbital fat, or both. The extra room allows crowded tissues to shift into the space that has been opened, so the pressure drops. In simple words, the surgery turns a “tight box” into a “slightly bigger box,” so the eye and its tissues are not crushed.
Orbital decompression is a surgery that makes extra room inside the eye socket (the “orbit”). In thyroid eye disease (TED, also called Graves’ orbitopathy), the tissues and muscles behind the eye swell and take up too much space. Because the bony socket is a closed box, the eye is pushed forward (bulging eyes/proptosis), the eyelids can’t close fully, and in severe cases the swollen tissues can squeeze the optic nerve and threaten sight. Decompression removes small sections of the bony walls and/or some orbital fat so the swollen tissues can expand into nearby sinus space. This lets the eye settle back, lowers pressure on the optic nerve, and protects the front of the eye from drying out. Most commonly, decompression is used for TED; it may also be used for other causes of severe proptosis. EyeWiki+1NCBI
The most common reason is thyroid eye disease (also called Graves’ orbitopathy). In this disease, the eye muscles and orbital fat become inflamed and enlarged. The eyes may bulge, the surface of the eyes may dry and ulcerate, and the optic nerve may be squeezed at the back of the orbit. Medicines like steroids, targeted immune drugs, and radiation can help, but some people still have pressure, bulging, or threatened vision. In those people, orbital decompression can protect the eye and improve function and comfort. The operation is also used for certain infections, cysts, sinus mucoceles, some tumors, and some bone conditions when they push on the orbit. It is also sometimes done for appearance and comfort when the active inflammation has settled, but the eyes remain very prominent.
How the operation helps
The surgery lowers pressure in two basic ways. First, removing small parts of one or more bony walls gives the swollen tissues somewhere to expand into (often into the nearby sinuses). Second, removing some fat inside the orbit reduces the volume inside the orbit. Both steps lessen the forward push on the eye and the squeeze on the optic nerve. With less pressure, the eye can sit farther back, the eyelids can close better, the cornea can heal, double vision may improve or become easier to treat, and the risk to the optic nerve drops.
Types of orbital decompression
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Orbital fat decompression
In this method, the surgeon removes a measured amount of the soft fat inside the orbit. This fat does not carry vision. Taking out a careful amount reduces the crowded volume. It can pull the eye back a few millimeters and lower pressure without cutting bone. It is often used in people with thyroid eye disease who have more fat expansion than muscle enlargement. It can be done through small incisions hidden inside the eyelids or conjunctiva. -
Medial wall decompression (often endoscopic through the nose)
The inner wall of the orbit borders the ethmoid sinus. A surgeon can go through the nose with an endoscope, open the thin bone of the medial orbital wall, and let the swollen orbital tissues gently expand into the sinus space. This can reduce forward bulging and pressure at the back of the orbit. Because the approach is through the nose, there is no skin scar. It is commonly used when there is pressure near the orbital apex or when the medial muscles are tight. -
Lateral wall decompression (often “deep lateral” decompression)
The outer wall of the orbit is thick. Behind it is a hollow area called the “sphenoid greater wing.” By thinning and partially removing the deep part of this wall, the surgeon creates a “pocket” the tissues can expand into. This technique can give strong reduction of eye bulging while having a lower risk of new double vision in some patients. It is often done through a hidden eyelid crease incision. -
Floor (inferior wall) decompression
The bottom wall of the orbit rests on the maxillary sinus. By partly removing this floor bone, tissues can settle downward into the sinus. Surgeons use it when extra “downward” room is helpful, such as in severe bulging or when the lower eyelid does not close well. It is often combined with another wall to balance the shift of tissues. -
Balanced decompression (medial + lateral walls)
Here the surgeon opens both the medial and lateral walls. This balances the way tissues move, pulling the eye back with less side-shift. It is often chosen in thyroid eye disease to get a good reduction in bulging while lowering the chance of the eye shifting sideways. -
Three-wall decompression (medial + lateral + floor)
This is a stronger form used when very large reductions are needed, such as severe bulging or threatened optic nerve function. Because more walls are opened, more tissue can expand, and the eye can move back more. It is powerful but requires careful planning to avoid new double vision. -
Orbital apex and optic canal decompression (targeted “back-of-the-orbit” work)
If the optic nerve is squeezed at the tight back end of the orbit (the apex) or in the optic canal, a surgeon can remove bone around those areas to relieve the pinch on the nerve. This is delicate work. It is used when vision is threatened and medicines are not working. -
Endoscopic endonasal decompression (through the nasal passages)
Using an endoscope through the nose, the surgeon can open the medial wall and sometimes the floor without any skin incisions. This method allows excellent access to the apex and the sinuses. It is useful when sinus disease or mucoceles push on the orbit, or when a medial/apical decompression is needed. -
Transconjunctival or transcaruncular approaches (hidden incisions inside the eyelids)
These paths let the surgeon reach the medial wall and floor from inside the eyelids. The incision is hidden, and healing can be quick. They are often used together with endoscopic work to tailor the decompression. -
Staged decompression as part of full thyroid eye disease care
In thyroid eye disease, surgery is often staged. First, decompression to set the eye back and protect the nerve. Later, if needed, eye muscle surgery to fix double vision. Lastly, eyelid surgery to improve closure and shape. Staging lets each step be accurate after the orbit has reached its new shape.
Indications for orbital decompression
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Thyroid eye disease with marked bulging
In this condition the muscles and fat swell. The eyes push forward. Decompression makes more space so the eyes can sit back and the lids can close. -
Thyroid eye disease with compressive optic neuropathy
At the back of the orbit, swollen muscles can squeeze the optic nerve. Urgent decompression lowers the squeeze and can save vision when medicines are not enough. -
Thyroid eye disease with severe exposure keratopathy
If the eyelids cannot close, the cornea dries and can ulcerate. Decompression pulls the eye back so the lids cover the eye better and the cornea is safer. -
Persistent painful pressure in thyroid eye disease
Some people live with deep, aching pressure even after medicines. Decompression lowers pressure and brings comfort when other care has failed. -
Subperiosteal abscess from sinus infection pushing the orbit
Pus trapped along the medial wall can push the eye. Surgical drainage and a medial wall decompression through the nose can relieve pressure and protect the eye. -
Paranasal sinus mucocele expanding into the orbit
A mucocele is a mucus-filled cyst that can slowly expand bone and press on the orbit. Decompression opens bone and lets the cyst be drained so pressure falls. -
Idiopathic orbital inflammation with crowding
Some people get severe orbital inflammation not tied to a known disease. If medicines fail and pressure persists, decompression can help relieve the crowding. -
Benign vascular orbital tumor with mass effect (e.g., cavernous venous malformation)
These slow-growing masses can push the eye forward. The main treatment is removal of the mass, but in selected cases, decompression can be part of pressure relief. -
Malignant orbital tumor causing compression (palliative or adjunct)
When a tumor cannot be fully removed or is treated with medicines and radiation, decompression can be used to reduce pressure and protect remaining vision. -
Optic nerve compression at the orbital apex
Any cause of apex crowding—swollen muscles, bone growth, or mass—can pinch the nerve. Targeted apex decompression opens bone around the pressure point. -
Craniosynostosis with shallow orbits (e.g., Crouzon syndrome)
If skull sutures fuse early, the orbits can be shallow. Combined craniofacial and orbital decompression creates more space so the eyes are protected. -
Fibrous dysplasia of the skull narrowing the orbit
Abnormal bone growth can thicken the orbital walls and the optic canal. Decompression of the tight bone can protect the nerve and reduce crowding. -
Osteopetrosis with optic canal narrowing
Very dense bone can constrict the optic canal. Carefully opening the canal can relieve nerve pressure. -
Sphenoid wing meningioma encroaching on the orbit
This tumor can thicken bone and narrow the lateral orbit and canal. Lateral wall and canal decompression, often with tumor care, can reduce pressure. -
Post-traumatic bony displacement compressing the orbit
After fractures, bone fragments or scarring can press on orbital tissues. Decompression and reconstruction restore space and lower pressure. -
Chronic organized orbital hematoma after trauma
Old blood can solidify and act like a mass. Removing it and decompressing tight bone can relieve the push on the eye. -
Invasive fungal sinusitis with orbital apex pressure
Aggressive infections can swell tissues and compress the nerve. Along with urgent antifungal treatment and debridement, decompression may help protect vision. -
Orbital apex inflammatory syndrome
Some immune conditions inflame the apex and squeeze the nerve. If medicines fail or vision drops fast, decompression can be used to relieve the squeeze. -
Rehabilitative reduction of disfiguring proptosis after the active phase of thyroid eye disease
When inflammation is quiet but the eyes remain very prominent, decompression is offered to set the eyes back for comfort and appearance. -
Selected metastatic disease to the orbit with mass effect
If cancer spreads to the orbit and causes pressure, decompression may be considered with the oncology team to preserve vision and comfort.
Person may need evaluation for orbital decompression
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Bulging of one or both eyes
The eye looks pushed forward. Glasses may no longer fit. People may comment that the eyes look “staring.” -
Eyelid retraction and a wide-eyed appearance
The upper lids ride high or the lower lids pull down. The white of the eye shows all around, and the eye feels exposed. -
Deep pressure or pain behind the eye
People often describe a heavy, aching feeling inside the orbit, worse at night or when bending. -
Double vision
Swollen or tight muscles can limit movement and cause two images, especially when looking up or sideways. -
Restricted eye movements
The eye may not move fully in certain directions, and attempts to move can be uncomfortable. -
Dryness, burning, or a gritty sensation
The surface of the eye dries when the lids do not cover it well, leading to irritation. -
Tearing and wateriness
Ironically, dry, exposed eyes can reflexively tear a lot, which can blur vision. -
Redness and swelling of the conjunctiva (chemosis)
The clear skin over the white of the eye can look swollen and jelly-like because of inflammation and venous congestion. -
Light sensitivity
An exposed cornea becomes sensitive to light and wind. -
Incomplete eyelid closure (lagophthalmos)
People may sleep with the eyes partly open or struggle to blink fully, causing morning irritation. -
Corneal pain, scratches, or ulcers
Dry, exposed corneas can develop surface damage, which hurts and can threaten vision. -
Headache or sinus-area pressure
Pressure around the eyes or cheeks can occur when swollen tissues push against the sinus walls. -
Blurred vision
The vision may blur from a dry cornea or, more seriously, from pressure on the optic nerve. -
Colors seem washed out (color desaturation)
When the optic nerve is under pressure, reds and other colors look faded compared with the other eye. -
Areas of missing side vision
People may notice dim or missing parts in their visual field, especially if the optic nerve is affected.
Diagnostic Tests Before Surgery
A) Physical exam tests
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Visual acuity test (reading the eye chart)
This measures how clearly each eye can see. A drop that is not explained by glasses can signal corneal problems from exposure or pressure on the optic nerve. Tracking the letters you can read over time shows whether vision is stable or worsening. -
Pupil exam for a relative afferent pupillary defect (RAPD)
The doctor shines light in each eye and watches the pupil reactions. If the optic nerve is squeezed, the affected eye’s pupil can react more weakly. This is a quick, bedside clue that the nerve may be in trouble. -
Color vision test (such as Ishihara plates or desaturation testing)
People with optic nerve problems often lose color brightness early, especially for red. Comparing the two eyes helps detect pressure on the nerve before central vision is severely affected. -
Exophthalmometry (Hertel measurement of eye protrusion)
A small device rests on the bony rims and measures how far forward each eye is. An increase in millimeters over time, or a large difference between eyes, confirms bulging and helps plan how much decompression might be needed. -
Corneal surface staining and tear film assessment
A harmless dye called fluorescein shows dry spots and scratches on the cornea under a blue light. If the lids do not close well because of bulging, this test shows the damage that must be prevented, which decompression can help by letting the lids cover better.
B) Manual tests performed by the examiner
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Ocular motility and diplopia mapping
The examiner moves a light or target in all directions and notes where double vision appears. This shows which muscles are tight or enlarged and guides both decompression planning and any later eye muscle surgery. -
Forced duction test
After numbing drops, the doctor gently grasps the eye’s surface with a tiny forceps and tries to move it. If the eye will not move, the restriction is mechanical, such as from a tight, enlarged muscle. This helps separate a nerve problem from a “tight muscle” problem. -
Force generation test
Here the patient tries to move the eye against gentle resistance. If strength is poor, the muscle may be weak rather than simply tight. This helps tailor surgery and predict how much double vision might change. -
Retropulsion test (digital orbital pressure test)
The examiner gently presses the eye backward through the closed lid to feel how “full” the orbit is. Very tight, non-compressible orbits suggest marked crowding, which is often improved by decompression.
C) Laboratory and pathological tests
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Thyroid function tests (TSH, free T4, sometimes T3)
Many patients with thyroid eye disease have abnormal thyroid hormone levels. These blood tests show whether the thyroid gland is underactive, overactive, or controlled. Good control of thyroid levels supports eye healing. -
Thyroid autoantibodies (TRAb or TSI; sometimes TPO)
These blood tests look for immune signals that drive thyroid eye disease. High levels often match active disease. Falling levels can mean the disease is calming, which can help timing surgery. -
Inflammation markers (ESR and CRP)
High numbers suggest active inflammation or infection. If these are raised, doctors may treat the inflammation or infection aggressively before or along with surgery. -
Complete blood count and blood cultures (if infection is suspected)
A high white blood cell count and positive cultures can confirm bacterial infection, such as a sinus source pushing on the orbit. Treating infection is urgent; decompression may be combined with drainage. -
Tissue biopsy and histopathology when a mass is present
If a tumor, mucocele, or unusual mass is seen on imaging, a small sample can be taken and studied under a microscope. This shows exactly what the tissue is, which guides whether decompression alone is right or if tumor removal, medicines, or radiation are needed.
D) Electrodiagnostic tests
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Visual evoked potentials (VEP)
Small electrodes measure how quickly and how strongly the brain responds to a visual pattern. Slowed or reduced signals suggest the optic nerve is not carrying vision well, which can occur when the nerve is under pressure. This test helps in difficult cases to confirm nerve involvement. -
Pattern electroretinography (pattern ERG)
This test measures the function of the retina’s ganglion cells, which send signals into the optic nerve. If pattern ERG is reduced, it can support that the visual pathway is stressed, and it can help separate retinal from optic nerve causes of vision loss.
E) Imaging tests
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CT scan of the orbits and sinuses with thin slices
CT shows bone in excellent detail. It maps the thickness of each orbital wall, the size of the sinuses, the tightness at the apex, and any fractures or mucoceles. Surgeons use CT to plan which walls to open and how much bone to thin or remove. -
MRI of the orbits and brain with fat suppression and contrast
MRI shows soft tissues clearly. It reveals how enlarged each muscle is, how inflamed the fat is, whether the optic nerve is squeezed, and whether there is a tumor or inflammation in the apex. MRI is especially helpful for planning in people with mainly muscle enlargement. -
Orbital ultrasound (B-scan)
Ultrasound can quickly show the size and shape of muscles and detect cystic or vascular lesions. It is useful in the clinic and can sometimes separate solid from fluid-filled masses. -
Optical coherence tomography (OCT) of the retinal nerve fiber layer and macula
OCT is like an optical ultrasound for the retina. If the nerve is under pressure, the nerve fiber layer can thin over time. OCT provides a clean baseline and helps monitor whether the nerve is staying healthy after treatment.
Disclaimer: Each person’s journey is unique, treatment plan, life style, food habit, hormonal condition, immune system, chronic disease condition, geological location, weather and previous medical history is also unique. So always seek the best advice from a qualified medical professional or health care provider before trying any treatments to ensure to find out the best plan for you. This guide is for general information and educational purposes only. Regular check-ups and awareness can help to manage and prevent complications associated with these diseases conditions. If you or someone are suffering from this disease condition bookmark this website or share with someone who might find it useful! Boost your knowledge and stay ahead in your health journey. We always try to ensure that the content is regularly updated to reflect the latest medical research and treatment options. Thank you for giving your valuable time to read the article.
The article is written by Team RxHarun and reviewed by the Rx Editorial Board Members
Last Updated: August 18, 2025.
