Stroke

Reference: Davidson 23rd; P- 1150 (Box-26.1)

Explanation: Infarct (85%), Haemorrhage (15%), venous (1%)

Reference: Davidson 23rd, Page: 1066 , Box : 25.2

Reference: Davidson 23rd; P-1088(Fig-25.19)

The 5 classic lacunar syndromes, established by Fisher in the 1960s and 1970s, are pure motor hemiparesis, pure sensory stroke, sensorimotor stroke, ataxic hemiparesis, and clumsy-hand dysarthria.

Stem Breakdown:

Sudden-onset severe headache ("thunderclap" headache), nausea, and vomiting: These are classic symptoms of a subarachnoid hemorrhage (SAH), a life-threatening condition often described as the "worst headache of my life."
Neck stiffness and photophobia: These symptoms suggest meningeal irritation, which occurs when blood irritates the meninges in SAH.
Blood in the subarachnoid space on CT: This confirms the diagnosis of SAH.
Option Analysis:

A) Subarachnoid hemorrhage: This is the correct diagnosis. Davidson and Harrison explain that subarachnoid hemorrhage (SAH) is most commonly caused by the rupture of a cerebral aneurysm, leading to bleeding into the subarachnoid space. The sudden onset of a severe headache, often described as "thunderclap," and the presence of blood on CT are diagnostic of SAH.
B) Migraine headache: Migraine can cause severe headache with nausea and photophobia, but it typically has a gradual onset and is often preceded by an aura. It is not associated with neck stiffness or blood in the subarachnoid space.
C) Meningitis: Meningitis can cause headache, neck stiffness, and photophobia, but it would not cause blood in the subarachnoid space on CT. Lumbar puncture would show infection (e.g., elevated white blood cells in the cerebrospinal fluid).
D) Tension headache: Tension headaches are usually mild to moderate, with a band-like distribution of pain around the head. They are not associated with sudden onset, nausea, vomiting, or blood in the subarachnoid space.

A) Retinal artery occlusion: This is the correct diagnosis. Davidson and Harrison explain that central retinal artery occlusion is caused by an embolus or thrombus blocking blood flow to the retina, leading to sudden, painless vision loss. The pale retina and "cherry red spot" are classic fundoscopic findings.
B) Retinal vein occlusion: Retinal vein occlusion causes painless vision loss, but the fundoscopy would show "blood and thunder" appearance with dilated veins, hemorrhages, and cotton-wool spots, not a pale retina with a cherry red spot.
C) Diabetic retinopathy: Diabetic retinopathy causes vision loss over time due to microvascular damage from diabetes. Fundoscopy reveals microaneurysms, hemorrhages, and neovascularization, not the findings described here.
D) Acute glaucoma: Acute glaucoma causes sudden, painful vision loss due to increased intraocular pressure. It is associated with a red, painful eye and a hazy cornea, not the fundoscopic findings described.

Explanation: CT is is the first line investigation of stroke

Explanation:
Stem Breakdown:

Sudden-onset weakness and difficulty speaking: These are classic signs of a stroke.
CT showing ischaemia in the left middle cerebral artery (MCA): This confirms that the stroke is ischaemic in nature.
Option Analysis:

A) Transient ischaemic attack (TIA): A TIA involves brief episodes of neurological dysfunction caused by temporary ischaemia without infarction. In this case, the CT scan shows ischaemia, indicating tissue damage, which rules out TIA.
B) Ischaemic stroke: This is the correct diagnosis. Davidson and Harrison explain that ischaemic strokes are caused by obstruction of a cerebral artery, leading to tissue infarction. Sudden-onset weakness (hemiparesis) and difficulty speaking (aphasia) are typical of a left MCA stroke.
C) Hemorrhagic stroke: Hemorrhagic stroke involves bleeding into the brain tissue, often presenting with a more severe clinical picture, including altered consciousness, headache, and vomiting. In this case, the CT shows ischaemia rather than haemorrhage.
D) Subdural haematoma: Subdural haematoma results from venous bleeding, typically following head trauma, and presents with a gradual onset of symptoms like confusion and headache. It does not present with acute ischaemic findings on CT.

A ruptured aneurysm is the most common cause of non-traumatic subarachnoid hemorrhage. Davidson explains that aneurysms, particularly berry aneurysms in the circle of Willis, are prone to rupture, causing bleeding into the subarachnoid space. Harrison highlights that patients typically present with a sudden, severe "thunderclap" headache, and diagnosis is confirmed with CT or lumbar puncture showing blood in the cerebrospinal fluid.

X-rays: used for fractures or foreign bodie
CT: Firrst line for stroke

Explanation: SAH typically presents with a sudden, severe, ‘thunderclap’ headache (often occipital), which lasts for hours or even days, often accompanied by vomiting, raised blood pressure and neck stiffness or pain. It commonly occurs on physical exertion, straining and sexual excitement.

Reference: Davidson 23rd, Page: 1160
Explanation: most common site of SAH are Anterior communicating artery (30%)

Explanation: CT is first line for stroke diagnosis

The Circle of Willis is an arterial polygon (heptagon) formed as the internal carotid and vertebral systems anastomose around the optic chiasm and infundibulum of the pituitary stalk in the suprasellar cistern

In SAH the pattern of headache is thunder cap in nature.

Davidson 23rd; P-1152