Presentation of Intracranial Aneurysms in Children

Symptoms and Signs

Intracranial aneurysms in the pediatric age group present with subarachnoid hemorrhage in 60–70% of cases (2). The rate of hemorrhage is higher in children younger than 5 years (80%) and lower in children older than 5 years (45%) or in those bearing a giant aneurysm (2). This specific form of aneurysm presents with rupture in only 35% of cases, whereas the prevailing mode of presentation is focal neurological signs and symptoms (e.g., cranial nerve deficits) due to mass effect and frequent location in the posterior fossa (2). Most children with ruptured aneurysms present in a good clinical status, i.e., Hunt and Hess grades I and II (7).
Common signs and symptoms encountered in children with intracranial aneurysms include:

• Headache: Acute headache is often due to rupture, classically described as thunderclap headache. A subacute onset of headache is common with mycotic aneurysms.
• Focal neurological deficits: This form of presentation may occur in children with dissecting aneurysms, which can lead to ischemic stroke, or with giant aneurysms, which exert local mass effect.
• Hydrocephalus: Hydrocephalus can be a result of hemorrhage or mass effect of the aneurysm itself.
• Impaired consciousness, irritability, vomiting: These symptoms suggest elevated ICP.
• Seizures

Patterns and time of evolution

• Subarachnoid hemorrhage: Patients with hemorrhage usually present with an acute onset of symptoms, although a “sentinel” or “warning” bleed is possible.
• Dissecting aneurysm: Patients with dissecting aneurysm may present with subacute ischemic symptoms (2).
• Giant aneurysm: Patients with giant aneurysm may present with progressive neurological deficits, e.g., cranial nerve compression (28).
• Traumatic aneurysm: Patients with traumatic aneurysm may present with an interval of several weeks to a few months between trauma and presentation (38).

Evaluation at Presentation

Pediatric aneurysms pose a diagnostic challenge for several reasons, such as:

• Low incidence: The low incidence and thus often scarce knowledge of this condition among physicians might delay diagnosis.
• Poor history: In children, depending on age, it might be difficult to obtain a conclusive history. The very young are unable even to express their complaints, e.g., sudden onset of severe headache.
• Delayed presentation: In cases of traumatic aneurysms, a longer interval between trauma and presentation might obscure the diagnosis.

The diagnostic algorithm upon presentation should be as follows:

• Physical examination: Physical examiniation should include a basic assessment of level of consciousness (e.g., by means of the GCS) and a neurological examination to detect focal deficits.
• Past medical history: Risk factors, such as predisposing conditions or previous head trauma, are of particular interest.
• Diagnostic imaging: As a next step, imaging should be obtained. A nonenhanced CT scan is the initial modality to diagnose intracranial hemorrhage. CT angiography is capable of detecting intracranial aneurysms, although DSA remains the gold standard. MRI and MR angiography can provide additional information in selected patients (23).
• Lumbar tap: In certain cases with diagnostic uncertainty a lumbar tap can be performed to rule out subarachnoid hemorrhage. Prior to lumbar puncture, an intracranial space-occupying lesion should be radiologically excluded.

Intervention at Presentation

Depending on the severity and evolution of symptoms, the following steps are recommended:

Stabilization

• Vascular access: Large bore IVs, arterial line, and central venous catheter should be discussed.
• Airway intubation: Although it should not be used as the sole criterion for intubation, a GCS ≤ 8 reflects significantly impaired consciousness, and intubation should be discussed.
• Blood pressure control: In the acute phase, especially in subarachnoid hemorrhage, normotension for the child’s age should be aimed for.
• Treatment of hydrocephalus and elevated ICP: An EVD might be indicated if hydrocephalus is present.
• Treatment of seizures: Antiepileptic medication should be administered in symptomatic epilepsy. 

Preparation for definitive intervention, nonemergent

• Diagnostic imaging: In a nonemergent setting DSA is commonly performed in addition to CT/MRI imaging.
• Preoperative blood tests: These should comprise all basic tests, including a coagulation screen, as well as blood typing and crossmatching.

Preparation for definitive intervention, emergent

• Diagnostic imaging: CT angiography is a faster alternative to DSA in an emergency situation.
• Preoperative blood tests: These should comprise all basic tests, including a coagulation screen, as well as blood typing and crossmatching.

Admission Orders

• Vital signs: Blood pressure (aim is normotension for age in the acute phase), heart rate, and oxygenation should be monitored.
• Activity: Prior to definitive treatment of the aneurysm, bed rest with the head of bed elevated at 30 degrees is recommended.
• CSF drainage parameters (in case an EVD was inserted prior to admission to ICU): The aim should be physiological ICP for age. We never drain more than 3–5ml CSF at a time to avoid provocation of rebleeding.
• Medication: While oral or intravenous nimodipine is standard treatment for adults with ruptured aneurysms, this drug should be very carefully administered to children. There are no controlled trials in children, and data from small series suggest a substantial risk of induced arterial hypotension (26). Deep sedation should be avoided whenever possible to allow for neurological assessment.