A 45-year-old hypertensive male patient presented in the casualty with 2-hour history of sudden onset of a severe headache associated with nausea and vomiting. On clinical examination, the patient had neck stiffness and right-sided ptosis. Rest of the neurological examination was normal. What is the clinical diagnosis? –

**Core Concept**
The patient's presentation of sudden onset severe headache, nausea, vomiting, neck stiffness, and right-sided ptosis is suggestive of a non-ruptured aneurysm or a subarachnoid hemorrhage (SAH) due to the rupture of an intracranial aneurysm. This condition is a medical emergency that requires prompt diagnosis and treatment.

**Why the Correct Answer is Right**
The patient's symptoms are consistent with the classic triad of SAH: sudden onset headache (often described as "the worst headache of my life"), nausea, and vomiting. The presence of neck stiffness and ptosis (drooping of the eyelid) further supports this diagnosis. The aneurysm likely ruptured, causing bleeding into the subarachnoid space, which leads to these symptoms. The rest of the neurological examination being normal suggests that the patient has not yet developed any focal neurological deficits.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not provided.
* **Option B:** This option is not provided.
* **Option C:** This option is not provided.
* **Option D:** This option is not provided.

**Clinical Pearl / High-Yield Fact**
The classic description of a SAH is often referred to as "thunderclap headache," which is a sudden, severe headache that reaches its peak intensity within 1 minute. This type of headache is often described as the "worst headache of my life."

**Correct Answer:** D. Subarachnoid hemorrhage due to the rupture of an intracranial aneurysm

✓ Correct Answer: C. Aneurysmal subarachnoid haemorrhage