What is the diagnostic approach for determining the presence of a brain bleed?

Diagnostic Approach for Determining the Presence of a Brain Bleed

Computed tomography (CT) is the gold standard for initial evaluation of suspected brain hemorrhage due to its high sensitivity for detecting acute blood. 1

Initial Imaging Selection

• CT head without IV contrast is the first-line diagnostic test for suspected brain hemorrhage with a rating of 9/9 (usually appropriate) according to ACR Appropriateness Criteria 1
• MRI head without IV contrast is an alternative to CT with a rating of 8/9, particularly valuable with susceptibility-weighted imaging (SWI) sequences 1
• CT is very sensitive for identifying acute hemorrhage and considered the "gold standard" while gradient echo (GRE) and T2* susceptibility-weighted MRI are equally sensitive for acute hemorrhage detection 1
• Time constraints, cost, proximity to emergency department, patient tolerance, clinical status, and MRI availability may preclude emergent MRI in many cases 1

Timing of Imaging

• Rapid neuroimaging with CT or MRI is recommended to distinguish ischemic stroke from intracerebral hemorrhage (Class I; Level of Evidence A) 1
• Brain imaging should be performed as soon as possible after onset of clinical symptoms suspicious of hemorrhage, ideally within 1 week to reliably demonstrate high density consistent with recent hemorrhage 1
• The earlier the time from symptom onset to first neuroimaging, the more likely subsequent images will demonstrate hematoma expansion 1

Follow-up Imaging

• In patients with initial negative CT but on anticoagulants (especially those on concurrent antiplatelet therapy), consider repeat head CT to evaluate for delayed intracranial hemorrhage 2
• Follow-up imaging is recommended in the event of abrupt neurologic deterioration to evaluate for hematoma expansion 1
• Non-contrast cerebral CT or MR imaging should be performed at defined time points after initial diagnosis (commonly at 24 hours, 7-10 days, 30 days, and 90 days) 1

Advanced Imaging Techniques

• CTA and contrast-enhanced CT may be considered to help identify patients at risk for hematoma expansion (Class IIb; Level of Evidence B) 1
• CTA, CT venography, contrast-enhanced CT, contrast-enhanced MRI, magnetic resonance angiography and venography, and catheter angiography can be useful to evaluate for underlying structural lesions 1
• Among patients undergoing head CT within 3 hours of ICH onset, 28-38% have hematoma expansion of greater than one-third on follow-up CT 1

Secondary Causes Assessment

• MRI, magnetic resonance angiography, magnetic resonance venography, CTA or CT venography can identify specific causes of hemorrhage, including arteriovenous malformations, tumors, moyamoya, and cerebral vein thrombosis 1
• Consider magnetic resonance venography or CT venography if hemorrhage location, relative edema volume, or abnormal signal in cerebral sinuses suggests cerebral vein thrombosis 1
• A catheter angiogram may be considered if clinical suspicion is high or non-invasive studies suggest an underlying vascular cause 1

Radiological Features Suggesting Secondary Causes

• Presence of subarachnoid hemorrhage
• Enlarged vessels or calcifications along the margins of the ICH
• Hyperattenuation within a dural venous sinus or cortical vein
• Unusual hematoma shape
• Presence of edema out of proportion to the time of presumed ICH
• Unusual hemorrhage location
• Presence of other abnormal structures in the brain (like a mass) 1

Patient Risk Factors to Consider

• Patients with lobar hemorrhage location, age <55 years, and no history of hypertension have higher likelihood of secondary causes of ICH requiring additional MRI beyond non-contrast CT 1
• Patients on anticoagulant drugs have increased risk of initial hemorrhage and mortality compared to non-anticoagulated patients 2
• Warfarin-related hemorrhages are associated with increased hematoma volume, greater risk of expansion, and increased morbidity and mortality 1

Clinical Severity Assessment

• A baseline severity score should be performed as part of the initial evaluation of patients with ICH (Class I; Level of Evidence B) 1
• The National Institutes of Health Stroke Scale (NIHSS) can be completed quickly and provides quantification that allows easy communication of event severity 1
• Glasgow Coma Scale (GCS) score is similarly well known and easily computed 1

Common Pitfalls to Avoid

• Relying solely on clinical features to differentiate hemorrhage from ischemia is unreliable - neuroimaging is mandatory 1
• Delaying imaging in patients with suspected brain hemorrhage can miss the opportunity to identify active bleeding that may proceed for hours after symptom onset 1
• Failing to consider secondary causes of hemorrhage in patients with atypical presentations or risk factors 1
• Not performing follow-up imaging in patients with clinical deterioration, which may miss hematoma expansion 1