A 20-year-old male presents with sudden onset of severe headache, nausea, and vomiting
Question : A 20-year-old male presents with sudden onset of severe headache, nausea, and vomiting, and nuchal rigidity on physical examination. What is the first diagnostic test to perform?
A. Head CT
B. Lumbar puncture
C. Head MRI
D. Cerebral angiography
Answer: A
Explanation: The patient's manifestations (sudden severe headache, nausea, vomiting, nuchal rigidity) suggest subarachnoid hemorrhage or meningitis. Head CT is fast and non-invasive, and can quickly rule out subarachnoid hemorrhage (showing high-density lesions in the subarachnoid space), which is the first diagnostic test. Lumbar puncture may cause herniation if there is increased intracranial pressure; head MRI is time-consuming; cerebral angiography is used to find the cause of subarachnoid hemorrhage (e.g., aneurysm) after initial diagnosis. Therefore, the correct answer is A.
