Aneurysm presentation-- random clinical pearls

Diagnosis
1.  Of patients with the worst headache of their life, ten percent have aneurysms
2.  Sensitivity of LP to detect aneurysms decreases by seven percent per day
3.  CT-A removes need for catheter angiography in those with more than 5 rbc's
4.  SAH- aneurysmal peaks in April and September and nadirs in June and July
5.  Population prevalence of aneurysm in 2 %
Treatment
6.  **FENESTRATION OF LAMINA TERMINALIS IS EASY, DECREASES HYDROCEPHALUS INCIDENCE FROM 13 TO 2 PERCENT AND ALLOWS LUMBAR DRAINS
7.   EEG is a "pseudoexam " under anesthesia
8.  St Julien NSURG 2008  cardiopulmonary bypass without a chest incision (endovascular)allows fine control of BP and avoids circulatory arrest, hypothermia improves outcomes ( outcome of St Julien)  Grade 0 , 1 (1.5 %), 2 (6.2%), 3 (12.1%), 4 (17.4 %).  CP bypass is good for giant aneurysms
9.  Fisher scale stratifies the risk of vasospasm .  Grade 1: no blood   Grade 2:  vertical layer < 1mm
      Grade 3:    vertical layer > 1 mm, local clot     Grade 4:  ICH/IVH but minimal or no SAH. GRADE  THREE IS MAXIMAL RISK> GRADE FOUR.  Risk of vasospasm is 23 %.   With modified Fisher scale, vasospasm is greatest with grade 4.  About 20-30 % of vasospasms stroke.
10.  Risk of rebleed is 4 % in first 24 hours, then 1-2 % per day for 4 weeks.  Cumulative risk is 20 % at 2 weeks, 30 % at one month, 40 % at 6 months. Ventriculostomy which otherwise can be lifesaving also can precipitate a rebleed.
10.  Risk of rebleed is