Man coughed and developed sudden severe headache and fainting. The most probable diagnosis is:
Ans: A (Subarachnoid hemorrhage) Ref: Harrison's Principles of Internal Medicine 18th editionExplanation:Subarachnoid HemorrhageExcluding head trauma, the most common cause of S AH is rupture of a saccular aneurysm.Other causes include bleeding from a vascular malformation (arteriovenous malformation or dural arterial-venous listula)Saccular ("Berry") Aneurysm2% of adults harbor intracranial aneurysmsThe three most common locations are theTerminal internal carotid arteryMiddle cerebral artery (MCA) bifurcationTop of the basilar artery.Mycotic aneurysms are usually located distal to the first bifurcation of major arteries of the circle of Willis.Most result from infected emboli due to bacterial endocarditis causing septic degeneration of arteries and subsequent dilation and rupture.PathophysiologySaccular aneurysms occur at the bifurcations of the large- to medium-sized intracranial arteriesRupture is into the subarachnoid space in the basal cisterns and often into the parenchyma of the adjacent brain.Approximately 85% of aneurysms occur in the anterior circulation, mostly on the circle of Willis.About 20%' of patients have multiple aneurysms, many at mirror sites bilaterally.Clinical ManifestationsMost unruptured intracranial aneurysms are completely asymptomatic.At the moment of aneurysmal rupture w ith major SAH, the ICP suddenly rises.This may account for the sudden transient loss of consciousness that occurs in nearly half of patients.Sudden loss of consciousness may be preceded by a brief moment of excruciating headache, but most patients first complain of headache upon regaining consciousness.Severe headache associated with exertion is the presenting complaint. The patient often calls the headache ''the worst headache of my life '; however, the most important characteristic is sudden onset.The headache is usually generalized, often with neck stiffness, and vomiting is common.Sudden headache in the absence of focal neurologic symptoms is the hallmark of aneurysmal rupture.Focal deficits can occur rarely.Anterior communicating artery or MCA bifurcation aneurysms may bleed enough to produce mass effect. The deficits that result can include hemiparesis, aphasia, and abulia.A third cranial nerve palsy, particularly when associated with pupillary dilation, loss of ipsilateral (but retained contralateral) light reflex, and focal pain above or behind the eye, may occur with an expanding aneurysm at the junction of the posterior communicating artery and the internal carotid artery.A sixth nerve palsy may indicate an aneury sm in the cavernous sinus, and visual field defects can occur with an expanding supraclinoid carotid or anterior cerebral artery aneurysm.Occipital and posterior cervical pain may signal a posterior inferior cerebellar artery or anterior inferior cerebellar artery aneurysm.Pain in or behind the eye and in the low temple can occur with an expanding MCA aneurysm.
Subarachnoid hemorrhage
Migraine
Cluster Headache
Posterior fossa tumor
Cerebrovascular