Retrobulbar Hematoma, Orbital Blowout Fracture, and Ocular Compartment Syndrome¶

After a punch to the eye, a baseball or elbow strike to the face, a fall, or a motor vehicle crash, a severely painful, rock-hard, bulging eye (proptosis) with falling vision is a time-critical surgical emergency known as Orbital Compartment Syndrome (OCS) from a Retrobulbar Hematoma. Because the human eye socket (orbit) is a rigid, four-walled bony box open only in the front, arterial bleeding behind the eyeball rapidly spikes intraorbital pressure above the pressure of the central retinal artery, strangling the retina and optic nerve within 60 to 120 minutes. Even when no retrobulbar blood clot is present, a fracture of the thin bony floor of the eye socket (Orbital Blowout Fracture) can trap the muscle that moves the eye upward, triggering a dangerous heart-slowing reflex (oculocardiac reflex), or force sinus air behind the eyeball if the person blows their nose. If anyone with facial or eye trauma develops a bulging eye, vision loss, double vision, nausea with slow heart rate, or numbness of the upper lip and cheek, call your local emergency number immediately via emergency numbers. Review related trauma protocols in eye injuries and emergency care, head injuries and concussion, and orbital cellulitis and cavernous sinus thrombosis.

Do this now¶

1. Call your local emergency number immediately (911 in the United States and Canada, 112 across the European Union, 999 in the United Kingdom) if an injured eye is bulging forward (proptosis), feels tight and rock-hard beneath swollen eyelids, has blurry or darkening vision, has a pupil that does not shrink normally when light shines in it, or cannot move upward without severe pain and nausea.
2. Sit the patient upright (at least 45 to 90 degrees) if a spinal cord injury is not suspected. Keeping the head elevated above the level of the heart uses gravity to lower arterial bleeding pressure and venous congestion inside the eye socket, slowing down the buildup of a retrobulbar hematoma.
3. Command the patient strictly: "DO NOT BLOW YOUR NOSE, do not sneeze with your mouth closed, and do not strain." An orbital blowout fracture cracks the paper-thin bone separating the eye socket from the air-filled maxillary and ethmoid sinuses. Blowing the nose acts like a high-pressure air pump, forcing sinus air through the fracture crack directly behind the eyeball (tension orbital emphysema), which can instantly blind the eye by compressing the optic nerve.
4. Check vision in the injured eye right now (covering the uninjured eye) and repeat the check every 10 minutes. Have the person read print, count how many fingers you are holding up, or state whether they can see hand motion or light. If visual acuity drops from reading letters to only counting fingers after a blow to the face, tell paramedics and the emergency room physician the exact minute vision started dropping so they perform an immediate bedside Lateral Canthotomy and Cantholysis (LCC) within the 90-minute ischemic window.
5. Protect the eye with a rigid, vaulted shield (or the bottom of a paper/foam cup taped to the brow bone and cheekbone) with ZERO pressure on the eyeball. Never wrap an elastic bandage tightly around a traumatized eye, and never press an ice pack directly onto a swollen eyelid; if there is an undetected tear in the eyeball wall (open globe injury) or a retrobulbar hematoma, external pressure will squeeze the contents of the eye out or accelerate optic nerve ischemia.
6. Keep the patient completely nothing by mouth (NPO) and treat nausea or vomiting immediately. Vomiting and retching cause violent spikes in venous and arterial pressure inside the head and eye socket, expanding retrobulbar bleeding, and patients with trapped eye muscles or retrobulbar hematomas often require urgent surgical decompression or operating room repair.

Decision tree: Triage of blunt periorbital trauma, proptosis, and blowout fractures¶

flowchart TD
    Start["Blunt Trauma to Eye, Cheek, or Forehead (Punch, Ball, Fall, or Crash)"] --> GlobeCheck{"Step 1: Rule Out Open Globe Rupture (Teardrop/peaked pupil, dark iris tissue protruding, 360-degree bloody conjunctival ballooning, or deflated eye)?"}

    GlobeCheck -->|"YES: Suspected Open Globe Rupture"| OpenGlobe["OPEN GLOBE PROTOCOL: 1. ZERO pressure on eye; do NOT check intraocular pressure (tonometry). 2. Tape rigid Fox eye shield or paper cup over bony rim. 3. Call 911 / 112 / 999 for emergency ophthalmology microsurgical repair, IV antibiotics, & antiemetics."]

    GlobeCheck -->|"NO: Globe Wall Appears Intact"| OCSCheck{"Step 2: Screen for Orbital Compartment Syndrome (Retrobulbar Hematoma): Painful bulging eye (proptosis), rock-hard tight lids, falling vision, or sluggish pupil (RAPD)?"}

    OCSCheck -->|"YES: Retrobulbar Hematoma / Ocular Compartment Syndrome"| Canthotomy["90-MINUTE SURGICAL EMERGENCY: 1. Call 911 / 112 / 999 Immediately; sit upright 45-90 degrees. 2. Alert ER Physician on arrival: Needs IMMEDIATE Bedside Lateral Canthotomy & Cantholysis BEFORE CT Scan. 3. Give IV Mannitol / Acetazolamide / Methylprednisolone as bridge."]

    OCSCheck -->|"NO: Normal Vision, Soft Orbit, No Proptosis"| MuscleTrapCheck{"Step 3: Check Extraocular Eye Movements (Look Up, Down, Left, Right): Is Upward Gaze restricted with double vision, OR accompanied by nausea, vomiting, and slow heart rate (<60 bpm)?"}

    MuscleTrapCheck -->|"YES: Restricted Upward Gaze + Bradycardia/Nausea (Especially in Child/Teen with 'White Eye')"| Trapdoor["TRAPDOOR ORBITAL FLOOR FRACTURE WITH MUSCLE ENTRAPMENT: 1. Emergency Department Orbital CT Scan NOW. 2. Monitor ECG for Oculocardiac Reflex (vagal bradycardia/heart block). 3. Requires urgent surgical release within 24 to 48 hours to prevent permanent muscle necrosis."]

    MuscleTrapCheck -->|"NO Muscle Entrapment or Bradycardia"| SimpleBlowout["SUSPECT UNCOMPLICATED ORBITAL BLOWOUT FRACTURE (Sunken eye / enophthalmos, numb cheek/upper lip, or crepitus): 1. Strictly NO nose blowing for 4 to 6 weeks. 2. Urgent Emergency Department CT of Orbits to evaluate fracture size and sinuses."]

Pathophysiology: How the eye socket becomes a lethal pressure cooker¶

1. The rigid anatomy of the bony orbit and canthal tendons¶

To understand why a small collection of blood or air behind the eye causes blindness so rapidly, consider the mechanical design of the human orbit: - Four Rigid Bony Walls: The eye socket is a pear-shaped, four-sided pyramid with an average internal volume of only 30 milliliters (\(30\text{ mL}\)), enclosed on the top (frontal bone / orbital roof), outside (zygomatic and sphenoid bones / lateral wall), bottom (maxilla / orbital floor), and inside (ethmoid and lacrimal bones / medial wall). - The Sealed Front Door: Across the front opening of the pyramid, the eyeball (globe) and orbital fat are held tightly inside the socket by a tough fibrous sheet (the orbital septum) and anchored like a guitar string to the bony rims by the medial canthal tendon and lateral canthal tendon (specifically its inferior and superior crura). - Volume-Pressure Compliance Curve: Normally, resting intraorbital and intraocular pressure (IOP) is 10 to 20 millimeters of mercury (\(\text{mmHg}\)). Because the bony walls cannot expand outward and the lateral canthal tendon prevents the eyeball from moving more than a few millimeters forward, the orbit can accommodate only about 4 to 5 milliliters of extra fluid before all tissue slack is exhausted. - Once a ruptured infraorbital artery, anterior or posterior ethmoidal artery, or ophthalmic artery branch bleeds more than 5 milliliters into the retrobulbar muscle cone (or after sinus air is forced in under pressure), intraorbital pressure skyrockets along an exponential curve to 40, 60, or over 80 mmHg.

2. The vascular strangulation cascade (Ocular Compartment Syndrome)¶

Just like acute compartment syndrome in a crushed lower leg or forearm (see crush injury and compartment syndrome), when pressure inside the enclosed orbital compartment exceeds the perfusion pressure of the small arteries feeding the eye and optic nerve: 1. Venous Outflow Collapse (\(>25\text{ to }30\text{ mmHg}\)): The thin-walled central retinal vein and vortex veins are squashed shut first, trapping venous blood inside the eye and worsening congestion. 2. Short Posterior Ciliary and Vasa Nervorum Ischemia (\(>35\text{ to }45\text{ mmHg}\)): The tiny micro-vessels feeding the anterior optic nerve head and retrobulbar optic nerve collapse, causing ischemic optic neuropathy. 3. Central Retinal Artery Occlusion (\(>60\text{ to }80\text{ mmHg}\)): When orbital and intraocular pressure approaches diastolic arterial blood pressure, the central retinal artery stops flowing during diastole (visible on an ophthalmoscope as a pulsating central retinal artery) and then shuts down completely. 4. The 60-to-120-Minute Survival Window: Primate and clinical trauma studies establish that once complete retinal and optic nerve ischemia begins in Orbital Compartment Syndrome, surgical decompression performed within 60 to 90 minutes restores normal or near-normal vision in over 85 percent of patients, whereas decompression delayed beyond 120 to 240 minutes (2 to 4 hours) frequently leaves the patient permanently blind in that eye.

3. The mechanics of an Orbital Blowout Fracture (Hydraulic vs. Buckling Theory)¶

Why does the floor or inner wall of the eye socket crack while the heavier bony rim around the outside of the eye stays unbroken? - The Hydraulic Mechanism: When a round object larger than 5 centimeters (2 inches) in diameter (such as a fist, baseball, cricket ball, or tennis ball) strikes the front of the eye, it pushes the eyeball backward into the 30-milliliter cone of incompressible orbital fat. That sudden hydraulic pressure wave blasts outward against all four bony walls and blows out the two thinnest "safety-valve" bones in the skull: 1. The Posterior-Medial Orbital Floor (Roof of the Maxillary Sinus): Only 0.5 millimeters thick, weakened further by the groove and canal carrying the infraorbital nerve (\(V_2\)). 2. The Medial Orbital Wall (Lamina Papyracea of the Ethmoid Sinus): Literally translated as the "paper-thin layer" (only 0.2 to 0.4 millimeters thick). - The Buckling Mechanism: A direct blow to the thick inferior orbital rim (cheekbone edge) transmits a mechanical shockwave backward that buckles the thin orbital floor directly behind it without rupturing the eyeball itself.

Comprehensive comparison of the 4 acute post-traumatic orbital emergencies¶

Detailed clinical guide to the 4 orbital trauma emergencies¶

1. Retrobulbar Hematoma and the Bedside Lateral Canthotomy & Cantholysis (LCC)¶

Why do patients with a retrobulbar hematoma still lose their sight in modern hospitals? The #1 reason is waiting for an orbital CT scan or waiting to measure intraocular pressure with a Tono-Pen before cutting the lateral canthal tendon. - Clinical Diagnosis at the Bedside (No CT Required): If a trauma patient (or a patient who recently underwent eyelid blepharoplasty, sinus surgery, or a retrobulbar anesthetic block) presents with the "4 Ps of Orbital Compartment Syndrome": 1. Pain (severe, deep aching orbital pain). 2. Proptosis (forward bulging of the globe with rock-hard resistance to gentle digital retropulsion over closed lids). 3. Pupil abnormality (an afferent pupillary defect [RAPD] on the swinging-flashlight test, or a sluggish dilated pupil). 4. Poor / Decreasing Vision (or inability to assess vision in an intubated trauma patient who has a rock-hard proptotic eye with an RAPD or Intraocular Pressure \(>40\text{ mmHg}\)). - How Lateral Canthotomy and Inferior Cantholysis Saves the Eye in 2 Minutes: - In the Emergency Department resuscitation bay, the physician injects 1 to 2 milliliters of lidocaine with epinephrine into the lateral corner of the eyelids (lateral canthus), clamps across the lateral canthus for 30 seconds with a hemostat to crush blood vessels, and makes a 1-centimeter horizontal cut with iris scissors (canthotomy). - Why Canthotomy Alone is Not Enough: Simply cutting the skin at the corner of the eye only drops orbital pressure by a few millimeters of mercury. The physician must then pull the lower eyelid away from the eyeball, feel with the tips of the scissors for the tight, guitar-string-like inferior crus of the lateral canthal tendon, and snip that tendon completely (inferior cantholysis). - The moment the inferior crus is cut, the lower eyelid falls completely loose, the eyeball moves forward 4 to 6 millimeters to decompress the retrobulbar space, intraorbital pressure plummets by 20 to 40 mmHg within seconds, and arterial blood rushes back into the central retinal artery and optic nerve.

2. Pediatric "White-Eyed" Trapdoor Fracture and the Lethal Oculocardiac Reflex¶

In children, teenagers, and young adults under age 20, the bones of the orbital floor are rich in elastic collagen and not yet brittle like adult bone: - When a child is hit in the eye by a ball, elbow, or knee, the thin orbital floor bends downward like a greenstick hinge, orbital fat and the inferior rectus muscle (which sits directly on the floor) herniate momentarily through the crack, and the elastic bone snaps right back into place like a spring-loaded trapdoor, clamping the inferior rectus muscle tightly in its jaws. - Why It Is Misdiagnosed as a Concussion: Because children's elastic bones snap back cleanly without shattering, there is often almost zero black eye, zero subconjunctival hemorrhage, and a completely normal-looking "white eye" on the outside. However, when the pinched inferior rectus muscle is stretched, it fires an intense afferent signal up the ophthalmic division of the trigeminal nerve (Cranial Nerve V) to the brainstem, which fires directly down the vagus nerve (Cranial Nerve X) to the heart and stomach (The Oculocardiac Reflex / Aschner Reflex). - The Concussion Trap: Because the child is vomiting repeatedly, looks pale and sweaty, feels dizzy/sleepy, and has a headache with a normal-looking eye on the outside, emergency staff frequently misdiagnose the child with a head injury or concussion and order a brain CT that misses the lower orbit. - How to Spot It Instantly: Check the child's heart rate (often profoundly slow at 35 to 55 beats per minute, with junctional escape beats or sinus arrest spikes) and ask the child to follow your finger and look straight UP toward the ceiling. If the injured eye cannot rotate upward past the midline and looking up triggers a wave of nausea, eye pain, and a drop in pulse on the cardiac monitor, the child has an entrapped trapdoor orbital fracture requiring urgent surgical release within 24 to 48 hours before the pinched muscle suffers permanent ischemic necrosis (Volkmann contracture of the eye muscle).

3. Infraorbital Nerve (\(V_2\)) Numbness: The Hidden Clue to an Orbital Floor Fracture¶

How can you tell at the scene of an accident whether a swollen black eye is just a soft-tissue bruise ("shiner") or an underlying bony orbital floor blowout fracture? - Run your finger lightly across the person's left and right lower cheek, the side of the nostril, the upper lip, and ask them if their upper front teeth feel "wooden" or numb (like after a dental Novocain shot). - The infraorbital nerve (a branch of the maxillary division of the trigeminal nerve, \(V_2\)) runs directly through a paper-thin bony tunnel inside the floor of the eye socket before exiting onto the cheek to supply sensation to the midface and upper teeth. - If a blow to the eye causes numbness or pins-and-needles in the upper lip, upper gums/teeth, and cheek on the same side, an orbital floor blowout fracture through the infraorbital canal is present until proven otherwise by an orbital CT scan.

4. Orbital Emphysema: Why Nose Blowing Turns a Simple Fracture into an Airway to the Orbit¶

When the medial wall (lamina papyracea) or floor of the orbit fractures, the sterile fat of the eye socket now communicates directly with the air-filled ethmoid or maxillary nasal sinuses: - Under normal breathing, air pressure inside the nose is low. - However, blowing the nose forcefully generates intranasal pressures of 60 to over 100 mmHg (equivalent to inflating a car tire). - That blast of non-sterile sinus air and mucus shoots through the bone crack into the eyelids (causing sudden ballooning of the eyelids with a crackling "Rice Krispies" subcutaneous crepitus feeling under your fingers) and behind the eyeball. - If a flap of sinus mucosa or orbital fat acts as a ball-valve (letting air in during nose blowing but trapping it so it cannot escape back into the sinus), the trapped air pocket compresses the central retinal artery and optic nerve (Tension Orbital Emphysema), causing acute blindness that requires emergency needle decompression of the retrobulbar air pocket. - In addition, forcing contaminated nasal sinus bacteria into the sterile orbital fat creates a high risk of sight-threatening orbital cellulitis and cavernous sinus thrombosis, which is why patients with sinus-communicating orbital fractures are barred from blowing their nose, scuba diving, or playing wind instruments for 4 to 6 weeks.

Always rule out a concurrent Open Globe Rupture before touching the eye¶

Whenever a fist, baseball, BB pellet, bottle cork, or shattered glass strikes the eye, the force that fractures the orbital bones can also burst the wall of the eyeball itself (Open Globe Rupture). Before allowing anyone to press on the eyelids or check orbital tension, inspect the eye visually for the Six Signs of an Open Globe Rupture: 1. A "Teardrop" or Peaked Pupil: The pupil is no longer round; it is pulled into a pointed teardrop shape pointing toward the corner of the cornea or sclera where the eyeball wall burst and the iris plugged the hole. 2. 360-Degree Bloody Ballooning of the Conjunctiva (Bullous Hemorrhagic Chemosis): The clear membrane over the white of the eye is swollen into a thick, bloody, jelly-like ring completely surrounding the cornea, hiding a scleral rupture underneath. 3. Dark Brown or Black Pigment (Uveal Prolapse) Sticking Out of the White of the Eye: Never try to wipe away a dark black or brown "dirt spot" on the sclera after trauma; it is the patient's iris or ciliary body protruding through a ruptured sclera. 4. An Abnormally Deep or Shallow/Flat Anterior Chamber (or Hyphema): The space behind the cornea is filled with layered blood (hyphema, see eye injuries) or looks collapsed compared to the other eye. 5. Extrusion of Clear Jelly (Vitreous Humor) on the surface of the eye. 6. Severe Vision Loss with a Soft, Deflated-Looking Eye.

If ANY sign of an open globe rupture is present, stop all physical manipulation immediately, tape a rigid vaulted Fox shield or the bottom of a paper cup over the bony brow and cheekbone with zero contact on the eye, keep the patient upright and calm, and call 911 / 112 / 999.

Regional emergency numbers and agency protocols¶

• United States and Canada: Dial 911 for immediate transport to a Level I or Level II Trauma Center with 24/7 Emergency Medicine and Ophthalmology / Oculoplastic Surgery capabilities. Under American College of Emergency Physicians (ACEP), Advanced Trauma Life Support (ATLS), and American Academy of Ophthalmology (AAO) guidelines, emergency physicians are trained and credentialed to perform immediate bedside Lateral Canthotomy and Cantholysis (LCC) prior to CT imaging for Orbital Compartment Syndrome.
• United Kingdom: Dial 999 (or 112). Under Royal College of Emergency Medicine (RCEM) and Royal College of Ophthalmologists (RCOphth) trauma guidelines, retrobulbar hemorrhage with visual loss is classified as an immediate surgical decompression emergency performed in the Emergency Department Resuscitation Room before radiology transfer.
• European Union: Dial 112. Follow European Resuscitation Council (ERC) and national maxillofacial/ophthalmic trauma pathways for immediate orbital decompression and maxillofacial CT angiography.
• Australia and New Zealand: Dial 000 in Australia or 111 in New Zealand. Follow RANZCO (Royal Australian and New Zealand College of Ophthalmologists) and ANZCOR ocular trauma guidelines.
• India and Asia-Pacific: Dial 112 in India, 119 in Japan and South Korea, or 995 in Singapore. Request direct transport to a tertiary trauma hospital equipped with CT imaging, emergency medicine airway/surgical capabilities, and ophthalmology coverage.

See emergency numbers for all international emergency dispatch numbers.

Frequently asked questions¶

Why can't I put an ice pack directly on a swollen black eye right after a hard hit?¶

Until a physician examines the eyeball and confirms that the wall of the globe is intact and there is no retrobulbar hematoma, placing the weight of an ice pack or pressing a cold compress directly onto the eyelid is dangerous. If there is a hidden scleral rupture (open globe), the weight of the ice pack can squeeze the internal lens and vitreous jelly out of the eye; if there is a retrobulbar hematoma, external pressure adds to the already-dangerous pressure strangling the optic nerve. Always shield the eye over the bony rim instead.

Why did my eye bulge out like a golf ball the moment I blew my nose after getting hit in the face?¶

The bone separating the inside and bottom of your eye socket from your nasal sinuses is less than half a millimeter thick and frequently cracks during blunt facial trauma even when the outside of your face looks fine. When you pinch your nostrils to blow your nose, you generate over 60 to 100 mmHg of air pressure inside your nasal passages, which blasts sinus air and bacteria right through that bone crack into your eyelids and behind your eyeball (**orbital emphysema**); if vision blurs or the eye feels tight after blowing your nose, go to the emergency room immediately.

Why is a child who is vomiting with a slow heart rate after getting hit in the eye often misdiagnosed with a concussion?¶

Children have flexible orbital floor bones that crack open on impact and snap right back shut like a spring-loaded trapdoor, pinching the inferior rectus eye muscle without leaving much of a black eye on the outside. Stretching that trapped eye muscle stimulates the trigeminal-vagal **oculocardiac reflex**, which causes severe nausea, vomiting, pale skin, lethargy, and a dangerously slow heart rate (bradycardia). Always ask any child with facial trauma to look straight up toward the ceiling; if one eye cannot move up, it is an entrapped orbital fracture, not just a concussion.

Does Lateral Canthotomy and Cantholysis leave a permanent disfiguring scar on the corner of the eyelid?¶

No; a bedside lateral canthotomy and inferior cantholysis is a minor, clean 1-centimeter snip at the outer natural crease of the eyelid where cosmetic oculoplastic surgeons routinely make incisions. Once the retrobulbar swelling resolves over several days, an ophthalmologist or plastic surgeon can easily stitch the tendon and corner of the eyelid back together with virtually invisible scarring, whereas failing to perform the cut within 90 minutes causes permanent, irreversible blindness.

Do all orbital blowout fractures require surgery to put a plate in the eye socket?¶

No; more than half of adult orbital floor and medial wall blowout fractures heal safely without surgery. Ophthalmologists and maxillofacial surgeons only operate Immediately (within 24 to 48 hours) if an eye muscle is mechanically trapped causing the oculocardiac reflex or unresolving double vision, or Subacutely (within 7 to 14 days once swelling goes down) if the fracture covers more than 50 percent of the orbital floor, causes persistent double vision in primary reading gaze, or causes the eyeball to sink backward (**enophthalmos**) by more than 2 millimeters.

Can I fly on an airplane or go scuba diving with an untreated orbital blowout fracture?¶

Airlines and ophthalmologists generally advise waiting until an orbital fracture with sinus communication or orbital air (pneumo-orbit) has been evaluated and cleared (typically 1 to 2 weeks for commercial cabin flights if retrobulbar air is present, because trapped air inside the eye socket expands by 25 to 30 percent at cabin altitude according to Boyle's Law, compressing the optic nerve). Scuba diving is strictly prohibited until full bony healing (4 to 8 weeks), as mask squeeze and sinus barotrauma can cause catastrophic orbital hemorrhage or emphysema.

Related guides¶

• Eye injuries and emergency care
• Eye foreign object, corneal abrasion, and welding flash
• Head injuries and concussion
• Orbital cellulitis, cavernous sinus thrombosis, and danger triangle facial infections

Sources and official guidance¶

• American College of Surgeons (ACS, United States) Committee on Trauma: Advanced Trauma Life Support (ATLS) Student Course Manual (Ocular Trauma and Emergency Orbital Compartment Syndrome / Lateral Canthotomy and Cantholysis protocols).
• American Academy of Ophthalmology (AAO, United States): EyeWiki and Clinical Statements on Management of Orbital Blowout Fractures, Pediatric White-Eyed Trapdoor Fractures, and Retrobulbar Hemorrhage.
• Royal College of Emergency Medicine (RCEM) and Royal College of Ophthalmologists (RCOphth, United Kingdom): Best Practice Guideline: Traumatic Orbital Compartment Syndrome and Emergency Lateral Canthotomy and Cantholysis.
• American College of Emergency Physicians (ACEP, United States): Clinical Procedures in Emergency Medicine: Acute Management of Ocular and Maxillofacial Trauma.
• Royal Australian and New Zealand College of Ophthalmologists (RANZCO): Clinical Guidelines for Acute Ophthalmic Trauma and Open Globe Protection.