title: Occurrence of vasospasm and infarction in relation to a focal monitoring sensor in patients after SAH: placing a bet when placing a probe?
abstract: BACKGROUND
  Vasospastic brain infarction is a devastating complication of aneurysmal subarachnoid hemorrhage (SAH). Using a probe for invasive monitoring of brain tissue oxygenation or blood flow is highly focal and may miss the site of cerebral vasospasm (CVS). Probe placement is based on the assumption that the spasm will occur either at the dependent vessel territory of the parent artery of the ruptured aneurysm or at the artery exposed to the focal thick blood clot. We investigated the likelihood of a focal monitoring sensor being placed in vasospasm or infarction territory on a hypothetical basis.
  
  
  METHODS
  From our database we retrospectively selected consecutive SAH patients with angiographically proven (day 7-14) severe CVS (narrowing of vessel lumen >50%). Depending on the aneurysm location we applied a standard protocol of probe placement to detect the most probable site of severe CVS or infarction. We analyzed whether the placement was congruent with existing CVS/infarction.
  
  
  RESULTS
  We analyzed 100 patients after SAH caused by aneurysms located in the following locations: MCA (n = 14), ICA (n = 30), A1CA (n = 4), AcoA or A2CA (n = 33), and VBA (n = 19). Sensor location corresponded with CVS territory in 93% of MCA, 87% of ICA, 76% of AcoA or A2CA, but only 50% of A1CA and 42% of VBA aneurysms. The focal probe was located inside the infarction territory in 95% of ICA, 89% of MCA, 78% of ACoA or A2CA, 50% of A1CA and 23% of VBA aneurysms.
  
  
  CONCLUSIONS
  The probability that a single focal probe will be situated in the territory of severe CVS and infarction varies. It seems to be reasonably accurate for MCA and ICA aneurysms, but not for ACA or VBA aneurysms.
authors: Department of Neurosurgery, Bern University Hospital, Inselspital, Bern, Switzerland. christian.ulrich@insel.ch
authors: Christian T
authors: CT
authors: Ulrich
authors: Christian
authors: C
authors: Fung
authors: Hartmut
authors: H
authors: Vatter
authors: Matthias
authors: M
authors: Setzer
authors: Erdem
authors: E
authors: Gueresir
authors: Volker
authors: V
authors: Seifert
authors: Juergen
authors: J
authors: Beck
authors: Andreas
authors: A
authors: Raabe
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002536:Cerebral Arteries / Q000503:physiopathology; D002544:Cerebral Infarction / Q000150:complications* / Q000175:diagnosis* / Q000503:physiopathology; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D016013:Likelihood Functions; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000295:instrumentation*; D011859:Radiography; D013345:Subarachnoid Hemorrhage / Q000150:complications* / Q000000981:diagnostic imaging; D020301:Vasospasm, Intracranial / Q000150:complications* / Q000175:diagnosis* / Q000503:physiopathology; D055815:Young Adult
references: Neurosurgery. 1980 Feb;6(2):198-210
references: 6767999
references: J Neurosurg. 1997 Sep;87(3):381-4
references: 9285602
references: Crit Care Med. 2002 Jun;30(6):1348-55
references: 12072693
references: Drugs Today (Barc). 2001 Aug;37(8):573-578
references: 12743639
references: Cerebrovasc Brain Metab Rev. 1991 Winter;3(4):336-61
references: 1772740
references: Stroke. 2009 Jul;40(7):2362-7
references: 19461029
references: Stroke. 2005 May;36(5):992-7
references: 15831836
references: Acta Neurochir (Wien). 1994;127(1-2):27-31
references: 7942177
references: Stroke. 1999 Jul;30(7):1402-8
references: 10390314
references: Stroke. 2007 Jun;38(6):1831-6
references: 17446425
references: J Neurosurg. 2001 May;94(5):740-9
references: 11354405
references: AJNR Am J Neuroradiol. 2001 Jun-Jul;22(6):1143-8
references: 11415911
references: Neurosurgery. 2004 Jun;54(6):1369-73; discussion 1373-4
references: 15157293
references: Intensive Care Med. 2004 Dec;30(12):2166-9
references: 15549254
references: Neurosurgery. 1986 Jan;18(1):1-6
references: 3945370
references: AJNR Am J Neuroradiol. 2004 Nov-Dec;25(10):1778-82
references: 15569745
references: J Neurosurg. 2003 Jun;98(6):1227-34
references: 12816269
references: Neurosurgery. 2009 Aug;65(2):316-23; discussion 323-4
references: 19625911
references: Crit Care Med. 2002 May;30(5):1062-70
references: 12006804
references: Nat Clin Pract Neurol. 2007 May;3(5):256-63
references: 17479073
references: J Neurosurg. 2003 Jun;98(6):1222-6
references: 12816268
references: J Neurosurg. 2005 Jul;103(1):9-17
references: 16121967
references: Neurosurgery. 2005 Apr;56(4):633-54; discussion 633-54
references: 15792502
references: Neurosurgery. 1986 Jun;18(6):808-25
references: 3526171
references: J Neurosurg. 1956 Jan;13(1):1-42
references: 13286725
references: Arq Neuropsiquiatr. 2001 Sep;59(3-B):676-80
references: 11593263
references: Lancet. 2007 Jan 27;369(9558):306-18
references: 17258671
references: Neurosurgery. 2007 Apr;60(4):658-67; discussion 667
references: 17415202
references: J Neurosurg. 2005 Dec;103(6):974-81
references: 16381183
references: Neurol Med Chir (Tokyo). 1979 Jan;19(1):103-7
references: 84350
references: Stroke. 2004 Aug;35(8):1862-6
references: 15218156
references: Neurosurgery. 1980 Jan;6(1):1-9
references: 7354892
references: Stroke. 1974 Jul-Aug;5(4):557-601
references: 4851187
references: Stroke. 2003 Jun;34(6):1382-8
references: 12750537