Charcot–Bouchard aneurysms are a common cause of intracranial hemorrhage. Signs and symptoms
A small, unchanging aneurysm will produce few, if any, symptoms. Before a larger aneurysm ruptures, the individual may experience such symptoms as a sudden and unusually severe headache, nausea, vision impairment, vomiting, and loss of consciousness, or no symptoms at all. Subarachnoid bleed
If an aneurysm ruptures, blood leaks into the space around the brain. This is called a subarachnoid hemorrhage. Onset is usually sudden without prodrome, classically presenting as a "thunderclap headache" worse than previous headaches. Symptoms of a subarachnoid hemorrhage differ depending on the site and size of the aneurysm. Symptoms of a ruptured aneurysm can include:
a sudden severe headache that can last from several hours to days
nausea and vomiting
drowsiness, confusion and/or loss of consciousness
visual abnormalities
meningism
dizzinessAlmost all aneurysms rupture at their apex. This leads to hemorrhage in the subarachnoid space and sometimes in brain parenchyma. Minor leakage from aneurysm may precede rupture, causing warning headaches. About 60% of patients die immediately after rupture. Larger aneurysms have a greater tendency to rupture, though most ruptured aneurysms are less than 10 mm in diameter. Microaneurysms
A ruptured microaneurysm may cause an intracerebral hemorrhage, presenting as a focal neurological deficit.Rebleeding, hydrocephalus (the excessive accumulation of cerebrospinal fluid), vasospasm (spasm, or narrowing, of the blood vessels), or multiple aneurysms may also occur. The risk of rupture from a cerebral aneurysm varies according to the size of an aneurysm, with the risk rising as the aneurysm size increases.
The CDC case definition was derived from clinical data and statistical analyses.The result was a symptom-category approach to a case definition, with three symptom categories: fatigue, mood–cognition, and musculoskeletal. To meet the case definition, the veteran of the 1990–91 Gulf War must have symptoms in two of the three categories and have experienced the illness for six months or longer ("duration").The original study also including a determination of severity of symptoms ("severity"). "Severe cases were identified if at least one symptom in each of the required categories was rated as severe. Of 1,155 participating Gulf War veterans, 6% had severe CMI, and 39% had mild to moderate CMI; of the 2,520 nondeployed era veterans Of 1,155 participating Gulf War veterans, 6% had severe CMI, and 39% had mild to moderate CMI; of the 2,520 nondeployed era veterans, 0.7% had severe and 14% had mild to moderate CMI." Treatment
A 2013 report by the Institute of Medicine reviewed the peer-reviewed published medical literature for evidence regarding treatments for symptoms associated with chronic multisymptom illness (CMI) in 1990–91 Gulf War veterans, and in other chronic multisymptom conditions.