Terson Syndrome – A Comprehensive Medical Guide

Overview

Terson syndrome refers to the occurrence of intra‑ocular hemorrhage (usually vitreous or sub‑retinal bleeding) that is associated with an acute intracranial event, most commonly a subarachnoid hemorrhage (SAH). The term was first described by Austrian ophthalmologist Moritz Terson in 1900 when he noted eye bleeding in patients with traumatic brain injury.

• Who it affects: Adults of any age, but the majority of cases occur in patients 40–70 years old because this age group has the highest incidence of aneurysmal SAH.
• Prevalence: In patients with SAH, intra‑ocular hemorrhage is reported in 8–20 % of cases (depending on the detection method); overall, Terson syndrome is considered a rare complication, affecting roughly 1 in 5,000–10,000 hospital admissions for intracranial hemorrhage.^{Mayo Clinic}

The syndrome is a neurologic‑ophthalmic emergency because the eye bleeding often signals a severe rise in intracranial pressure (ICP) and may lead to permanent visual loss if not promptly addressed.

Symptoms

Symptoms can be ocular, neurologic, or systemic, reflecting both the underlying brain bleed and the eye bleed.

Ocular symptoms

• Sudden loss of vision: Ranges from mild blurring to complete blackout, usually in one eye but can be bilateral.
• Floaters or “cobwebs”: Dark, moving specks caused by blood cells floating in the vitreous.
• Redness or “blood spots”: May be visible on the sclera if hemorrhage is extensive.
• Pain: Rare; most patients report painless vision change, but increased intra‑ocular pressure can cause discomfort.
• Photophobia: Sensitivity to light, especially if the hemorrhage is near the retina.

Neurologic/systemic symptoms (from the underlying intracranial event)

• Sudden “thunderclap” headache
• Neck stiffness or meningismus
• Nausea, vomiting
• Loss of consciousness or altered mental status
• Focal neurological deficits (weakness, speech difficulty)
• Seizures

Causes and Risk Factors

Terson syndrome is not a primary disease; it is a secondary manifestation of a rapid increase in intracranial pressure that forces blood into the optic nerve sheath and then into the eye.

Primary causes

• Aneurysmal subarachnoid hemorrhage (SAH): The most common trigger (≈70 % of cases). Rupture of a cerebral aneurysm leads to a sudden surge in ICP.
• Traumatic brain injury (TBI): Severe closed‑head trauma can cause a rapid ICP rise.
• Intracerebral hemorrhage, intracerebral infarction with hemorrhagic conversion, or venous sinus thrombosis: Any acute intracranial bleed that abruptly elevates pressure.
• Severe coughing, Valsalva maneuvers, or acute hypertension: Rarely reported in case series where a sudden pressure spike leads to ocular bleeding.

Risk factors for the underlying intracranial event

• Smoking and hypertension (major risk for aneurysm formation and rupture)
• Polycystic kidney disease, connective‑tissue disorders (e.g., Ehlers‑Danlos, Marfan)
• Family history of cerebral aneurysms
• Heavy alcohol use and illicit drug use (cocaine, amphetamines)
• Age > 40 years and female sex (higher aneurysm prevalence)

Diagnosis

Because Terson syndrome straddles neurology and ophthalmology, a coordinated approach is essential.

Initial assessment

1. Neurologic evaluation: Glasgow Coma Scale, neuro‑imaging (CT or CTA) to confirm intracranial bleed.
2. Ophthalmic examination: Bedside funduscopy (direct or indirect ophthalmoscopy) performed by an ophthalmologist or trained neuro‑intensivist.

Imaging and tests

• Computed tomography (CT) of the head: Detects SAH, intracerebral hemorrhage, mass effect, and estimates ICP.
• CT angiography (CTA) / MR angiography (MRA): Identifies aneurysm location.
• Ocular ultrasound (B‑scan): Useful when media opacity (e.g., dense vitreous hemorrhage) limits direct visualization.
• Optical coherence tomography (OCT): Provides high‑resolution cross‑sectional images of retinal layers, helpful for sub‑retinal hemorrhage.
• Fluorescein angiography: Rarely needed, but can delineate retinal vascular leakage.

Diagnostic criteria (clinical)

Presence of an acute intracranial hemorrhage plus any of the following documented intra‑ocular bleeding:

• Vitreous hemorrhage
• Sub‑retinal hemorrhage
• Pre‑retinal (sub‑hyaloid) hemorrhage

Treatment Options

Management focuses on two fronts: stabilizing the life‑threatening intracranial event and addressing the eye hemorrhage to preserve vision.

Neurosurgical / medical management of the intracranial bleed

• Aneurysm securing: Endovascular coiling or surgical clipping (within 24–72 hours of SAH) to prevent re‑bleeding.
• ICP control: Osmotic agents (mannitol, hypertonic saline), head of bed elevation, controlled ventilation, and, if needed, external ventricular drainage.
• Blood pressure management: Target systolic BP < 140 mm Hg (per AHA/ASA guidelines).
• Seizure prophylaxis: Levetiracetam is commonly used in the acute phase.
• Vasospasm prevention: Nimodipine (60 mg q4h) for 21 days post‑SAH.

Ophthalmic interventions

1. Observation: Small, non‑central vitreous hemorrhages may clear spontaneously in 4–12 weeks.
2. Pars plana vitrectomy (PPV): Surgical removal of dense vitreous blood, indicated when:
   • Vision does not improve after 4–6 weeks
   • Dense hemorrhage obscures the retina, risking proliferative vitreoretinopathy
   • Patient is a good surgical candidate (stable neurologically).
   Success rates for visual recovery after PPV in Terson syndrome range from 70–85 %.^NIH
3. Intravitreal tissue‑plasminogen activator (tPA): Occasionally used to liquefy clot before PPV, though off‑label.
4. Laser photocoagulation: For peripheral sub‑retinal hemorrhage that threatens the macula.

Adjunctive therapies

• Corticosteroids: Short courses may reduce inflammatory edema but have no proven benefit for clearing hemorrhage.
• Anti‑VEGF agents: Not routinely indicated; reserved for secondary neovascular complications.

Living with Terson Syndrome

Even after acute treatment, patients often need ongoing care to regain full visual function and cope with residual deficits.

Vision rehabilitation

• Low‑vision aids (magnifiers, high‑contrast reading glasses)
• Occupational therapy to adapt daily tasks
• Computer software with screen‑reading or magnification features

Follow‑up schedule

1. First ophthalmology visit: Within 1–2 weeks after discharge.
2. Subsequent visits: Every 4–6 weeks until hemorrhage resolves, then semi‑annual for the first year.
3. Neuro‑rehabilitation: Physical, speech, or cognitive therapy as indicated by the brain injury.

Lifestyle adjustments

• Protect eyes from trauma (safety glasses during high‑risk activities).
• Avoid activities that drastically increase intracranial pressure (straining, heavy lifting) for at least 6 weeks post‑event.
• Maintain a healthy blood pressure and cholesterol profile.
• Quit smoking; limit alcohol intake.

Prevention

Because Terson syndrome is secondary, prevention focuses on reducing the risk of the primary intracranial bleed.

• Screening for cerebral aneurysms in high‑risk groups (family history, polycystic kidney disease) using MRA or CTA.
• Control hypertension (target < 130/80 mm Hg) through diet, exercise, and medication.
• Smoking cessation programs.
• Limit caffeine and illicit stimulant use.
• Regular check‑ups for connective‑tissue disorders.
• Prompt treatment of head trauma (wear helmets, use seat belts).

Complications

If the intra‑ocular component is not addressed, several complications can arise:

• Permanent visual loss: Dense vitreous or sub‑retinal hemorrhage can scar the retina.
• Proliferative vitreoretinopathy (PVR): Fibrocellular membranes contract and detach the retina.
• Epiretinal membrane formation leading to distortion (metamorphopsia).
• Secondary glaucoma: Elevated IOP from blood obstructing outflow.
• Re‑bleeding: Rare but possible if the underlying intracranial source remains unsecured.
• Neuro‑cognitive deficits: Related to the primary SAH, not the eye bleed, but can impair rehabilitation.

When to Seek Emergency Care

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Sources: Mayo Clinic, American Heart Association/American Stroke Association guidelines, National Institute of Neurological Disorders and Stroke (NINDS), Cleveland Clinic, peer‑reviewed articles from Journal of Neurosurgery and Ophthalmology Retina (2020‑2023).