A woman presenting with abrupt onset of “the worst headache of her life” Which is the best investigation?
**Core Concept**
Non-contrast computed tomography (CT) of the head is the preferred initial imaging modality in suspected acute ischemic stroke or hemorrhagic stroke, particularly in cases of sudden onset severe headache, as it rapidly provides crucial information on the nature and location of the lesion.
**Why the Correct Answer is Right**
The non-contrast CT scan is the most appropriate initial investigation due to its rapid acquisition time and ability to differentiate between ischemic and hemorrhagic stroke. This is critical in the acute setting, as timely intervention can significantly impact patient outcomes. The non-contrast CT scan can quickly identify hemorrhage, which is a medical emergency, and also detect early signs of ischemic stroke.
**Why Each Wrong Option is Incorrect**
**Option A:** Magnetic Resonance Imaging (MRI) is not typically the first-line imaging modality in acute stroke due to its longer acquisition time and limited availability in emergency settings.
**Option B:** CT angiography may be useful in some cases to evaluate the cerebral vasculature, but it is not the primary investigation in acute stroke.
**Option C:** Positron Emission Tomography (PET) is not typically used in the acute management of stroke.
**Clinical Pearl / High-Yield Fact**
In cases of suspected stroke, remember the "BEFAST" criteria: Balance, Eye, Face, Arm, Speech, Time (to call for emergency services). Early recognition and imaging are crucial in acute stroke management.
**Correct Answer:** A. Non-contrast CT of the head.