Berry Aneurysm
Content of This Page
1- Introduction
2- Causes
3- Symptoms
4- Investigations & Lab Results
5- Complications
6- Treatment
Introduction
A Berry Aneurysm, also known as a saccular aneurysm, is a small, rounded outpouching that occurs on the walls of cerebral arteries, typically at branching points in the circle of Willis. These aneurysms resemble a berry hanging on a stem, hence the name. Berry aneurysms are the most common type of intracranial aneurysm and can remain asymptomatic for years. However, if they rupture, they cause a subarachnoid hemorrhage, a serious and potentially life-threatening type of stroke characterized by bleeding into the space surrounding the brain.

Causes
Congenital weakness in the arterial wall: Defects in the internal elastic lamina and media layers make vessel walls prone to bulging.
Hypertension: High blood pressure increases stress on artery walls, promoting aneurysm formation.
Atherosclerosis: Plaque buildup can weaken vessel walls.
Genetic factors and connective tissue disorders: Conditions like polycystic kidney disease, Ehlers-Danlos syndrome, and Marfan syndrome increase risk.
Smoking: Damages blood vessels and accelerates aneurysm development.
Age and sex: More common in adults over 40 and slightly more frequent in females.
Trauma or infection: Rarely, vessel injury or infections can contribute.

Symptoms
-Symptoms of Unruptured Berry Aneurysm
Often asymptomatic and found incidentally.
If large, may cause pressure effects on nearby structures:
Headache
Cranial nerve palsies (e.g., third nerve palsy causing double vision and drooping eyelid)
Visual disturbances
Pain above or behind the eye
-Symptoms of Ruptured Berry Aneurysm (Subarachnoid Hemorrhage)
Sudden, severe “thunderclap” headache — often described as the worst headache of life.
Neck stiffness (meningismus) due to meningeal irritation.
Nausea and vomiting.
Photophobia (sensitivity to light).
Loss of consciousness or altered mental status.
Focal neurological deficits (weakness, speech problems) depending on bleeding location.
Seizures (less common).
Investigations & Lab Results
1. Imaging Studies
Computed Tomography (CT) Scan of the Head
First-line imaging if rupture is suspected (subarachnoid hemorrhage).
Detects acute bleeding in the subarachnoid space.
CT Angiography (CTA)
Non-invasive imaging to visualize cerebral blood vessels and identify aneurysms.
Magnetic Resonance Imaging (MRI) and Magnetic Resonance Angiography (MRA)
Helpful for detecting unruptured aneurysms and assessing surrounding brain tissue.
Digital Subtraction Angiography (DSA)
Gold standard for detailed visualization of aneurysm size, shape, and location.
Often used before surgical or endovascular treatment.
2. Laboratory Tests
Complete Blood Count (CBC)
To check for anemia or infection.
Coagulation Profile (PT/INR, aPTT)
Important prior to any surgical intervention.
Electrolytes and Renal Function Tests
Assess overall medical status before treatment.
Other Tests
May include cardiac evaluation if embolic sources are suspected.
Complications
Rupture leading to subarachnoid hemorrhage (SAH):
Life-threatening bleeding into the space around the brain causing sudden severe headache, loss of consciousness, and high mortality.
Rebleeding:
Increased risk of another rupture soon after the first bleed, worsening outcomes.
Hydrocephalus:
Accumulation of cerebrospinal fluid due to blockage of its pathways by blood, causing increased intracranial pressure.
Vasospasm:
Narrowing of cerebral arteries after SAH, leading to delayed ischemic stroke.
Seizures:
Resulting from brain irritation or injury.
Permanent neurological deficits:
Including paralysis, cognitive impairment, or cranial nerve palsies.
Death:
Due to severe hemorrhage or complications.
Treatment
1. Unruptured Berry Aneurysm
Observation and Monitoring:
Small, asymptomatic aneurysms may be monitored regularly with imaging if risk of rupture is low.
Risk Factor Control:
Manage hypertension, stop smoking, and control other vascular risk factors.
Elective Intervention:
Considered for aneurysms larger than 7 mm, those causing symptoms, or with high-risk features.
2. Ruptured Berry Aneurysm (Subarachnoid Hemorrhage)
Emergency Care:
Stabilize airway, breathing, circulation.
Control blood pressure to reduce rebleeding risk.
Definitive Treatment to Secure the Aneurysm:
Surgical Clipping:
Open brain surgery to place a clip at the aneurysm neck to prevent bleeding.
Endovascular Coiling:
Minimally invasive procedure where coils are inserted via catheter to fill and seal the aneurysm.
Supportive Care and Complication Management:
Prevent and treat vasospasm (e.g., nimodipine).
Manage hydrocephalus (e.g., ventricular drain).
Control seizures and provide intensive neurocritical care.