A simple and quantitative method to predict symptomatic vasospasm after subarachnoid hemorrhage based on computed tomography: Beyond the fisher scale

David A. Wilson, Peter Nakaji, Adib A. Abla, Timothy D. Uschold, David J. Fusco, Mark E. Oppenlander, Felipe C. Albuquerque, Cameron G. McDougall, Joseph M. Zabramski, Robert F. Spetzler

Research output: Contribution to journalArticle

Abstract

BACKGROUND: Although the Fisher scale is commonly used to grade vasospasm risk in aneurysmal subarachnoid hemorrhage (aSAH) patients, it fails to account for increasing subarachnoid hemorrhage (SAH) thickness. OBJECTIVE: We developed a simple quantitative scale based on maximal SAH thickness and compared its reproducibility and ability to predict symptomatic vasospasm against the Fisher scale. METHODS: The incidence of radiographic and symptomatic vasospasm among 250 aSAH patients treated at our institution was investigated. Admission head computed tomography scans were graded according to the Fisher scale and the proposed scale, which assigns a score from 1 to 5 based on a single measurement of maximum SAH thickness. We calculated vasospasm risk per grade for the Fisher scale and the proposed scale, and compared inter-and intraobserver variability for both scales. RESULTS: Forty-five patients (20.6%) developed symptomatic vasospasm. On the proposed scale, grade 5 patients were at highest risk, with an odds ratio for symptomatic vasospasm of 11 (95% confidence interval [CI] 2.27-53.37). Odds ratios for proposed grades 4 and 3 were 4.63 (95% CI 1.10-19.59) and 3.04 (95% CI 0.85-10.90), respectively. The odds ratio for Fisher grade 3 was 3.3 (0.96-11.30). Mean inter-and intraobserver agreement was greater for the proposed scale in comparison with the Fisher scale (κ0.65 and κ0.81 vs κ0.51 and κ0.35, respectively). CONCLUSION: The new scale accounted for increasing SAH thickness and was superior to the Fisher scale in inter-and intraobserver agreement and in predicting symptomatic vasospasm, particularly among the highest-risk patients.

Original languageEnglish (US)
Pages (from-to)869-875
Number of pages7
JournalNeurosurgery
Volume71
Issue number4
DOIs
StatePublished - Oct 1 2012
Externally publishedYes

Keywords

  • Computed tomography
  • Fisher scale
  • Subarachnoid hemorrhage
  • Vasospasm

ASJC Scopus subject areas

  • Surgery
  • Clinical Neurology

Fingerprint Dive into the research topics of 'A simple and quantitative method to predict symptomatic vasospasm after subarachnoid hemorrhage based on computed tomography: Beyond the fisher scale'. Together they form a unique fingerprint.

  • Cite this

    Wilson, D. A., Nakaji, P., Abla, A. A., Uschold, T. D., Fusco, D. J., Oppenlander, M. E., Albuquerque, F. C., McDougall, C. G., Zabramski, J. M., & Spetzler, R. F. (2012). A simple and quantitative method to predict symptomatic vasospasm after subarachnoid hemorrhage based on computed tomography: Beyond the fisher scale. Neurosurgery, 71(4), 869-875. https://doi.org/10.1227/NEU.0b013e318267360f