title: Semiquantitative software SPECT analysis in aneurysmal subarachnoid hemorrhage-related vasospasm.
abstract: BACKGROUND
  Cerebral vasospasm is a major cause of morbidity and mortality among patients after subarachnoid hemorrhage (SAH) from ruptured intracranial aneurysms. Patients are often monitored using transcranial Doppler (TCD) ultrasound and single photon emission computed tomography (SPECT) techniques. Historically SPECT has been evaluated qualitatively, though quantitative analysis software is now used to evaluate other cerebral pathologies.
  
  
  OBJECTIVE
  Our aim was to evaluate the utility of semiquantitative SPECT using Hermes brain registration and analysis software (BRASS) relative to TCD ultrasound and qualitative SPECT interpretation within a cohort of patients, all with cerebral vasospasm as measured by digital subtraction angiography.
  
  
  METHODS
  Retrospective analysis of 32 nonconsecutive patients, admitted for aneurysmal SAH examining perfusion deficits in terms of anterior, middle, and posterior vascular distributions using both TCD ultrasonography and brain perfusion SPECT studies.
  
  
  RESULTS
  McNemar analysis of accuracy between modalities showed a better overall performance trend for qualitative SPECT versus BRASS SPECT (Fisher exact = 0.99) and a statistically significant better performance of qualitative SPECT versus TCD in measuring anterior cerebral artery vasospasm (Fisher exact = 0.035). BRASS SPECT, however, performed better than qualitative SPECT in diagnosing posterior circulation vasospasm (Fisher exact = 0.180 vs. 0.358) and had greater specificity in determining anterior circulation vasospasm (71 vs. 57%).
  
  
  CONCLUSIONS
  BRASS SPECT is a useful method for evaluating cerebral perfusion and needs further optimization, particularly as it pertains to establishing semiquantitative cerebral perfusion parameters. It can serve as an adjunct to traditional SPECT evaluation of SAH particularly in determining subtle changes in the perfusion of the anterior and posterior arterial distributions.
authors.affiliation: Department of Radiology, University of Washington School of Medicine, Seattle, Washington 98195, USA. dcooke@u.washington.edu
authors.forename: Daniel
authors.initials: D
authors.lastname: Cooke
authors.forename: Bhasker
authors.initials: B
authors.lastname: Koppula
authors.forename: Douglas
authors.initials: D
authors.lastname: Seiler
authors.forename: Joseph
authors.initials: J
authors.lastname: Rajendran
authors.forename: Danial
authors.initials: D
authors.lastname: Hallam
authors.forename: Basavaraj
authors.initials: B
authors.lastname: Ghodke
authors.forename: David
authors.initials: D
authors.lastname: Lewis
mesh_terms: D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction; D001921:Brain / Q000000981:diagnostic imaging; D015331:Cohort Studies; D003545:Cysteine / Q000031:analogs & derivatives; D004453:Echoencephalography; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008297:Male; D008875:Middle Aged; D015609:Organotechnetium Compounds; D012189:Retrospective Studies; D012984:Software; D013345:Subarachnoid Hemorrhage / Q000150:complications*; D015899:Tomography, Emission-Computed, Single-Photon; D017585:Ultrasonography, Doppler, Transcranial; D020301:Vasospasm, Intracranial / Q000000981:diagnostic imaging* / Q000209:etiology*; D055815:Young Adult
chemical_list: D015609:Organotechnetium Compounds; C059659:technetium Tc 99m bicisate; D003545:Cysteine