Diagnostic accuracy of whole-brain computed tomography perfusion for detection of ischemic stroke in patients with mild neurological symptoms

Abstract

Mild and minor acute neurological symptoms may lead to diagnostic uncertainty, resulting in a heterogeneous group of patients with true ischemic events and stroke mimics with a potential for poor outcomes. More than half of ischemic stroke patients present as minor strokes (National Institutes of Health Stroke Scale score <6). Whole-brain computed tomography perfusion can be used as a diagnostic test for minor stroke, offering a potential method of reducing diagnostic uncertainty in these patients. We hypothesize that whole-brain computed tomography perfusion imaging features could accurately predict infarction in patients with minor neurological deficits. This retrospective chart review enrolled consecutive patients suspected of acute ischemic stroke with a National Institutes of Health Stroke Scale score <6, who underwent whole-brain computed tomography perfusion and follow-up diffusion-weighted magnetic resonance imaging at our institution. Sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios were calculated for whole-brain computed tomography perfusion, using follow-up diffusion-weighted magnetic resonance imaging as a reference standard. A total of 524 patients (mean age: 67 years; range: 17–96 years; 56% men) met the inclusion criteria. Patients were excluded for non-diagnostic (n = 25) or missing maps (n = 8) scans, non-ischemic findings (n = 7), and lack of follow-up magnetic resonance imaging (n = 336). The final analysis included 148 patients who underwent diffusion-weighted magnetic resonance imaging. Whole-brain computed tomography perfusion has a sensitivity of 0.57 (95% CI: 0.45–0.69) and a specificity of 0.82 (95% CI: 0.71–0.90). The positive and negative predictive values and positive and negative likelihood ratios were 75%, 67%, 3.09, and 0.53, respectively. Our analysis suggests that although whole-brain computed tomography perfusion may offer some value as an adjunctive test for improving confidence in offering stroke treatment, it is not sufficiently sensitive or specific to accurately predict cerebral infarcts in patients with minor neurological symptoms.

Keywords

Stroke computed tomography perfusion cerebral infarction diagnosis

Get full access to this article

View all access options for this article.

References

Dhamoon

Moon

Paik

et al.

Long-term functional recovery after first ischemic stroke: the Northern Manhattan Study. Stroke 2009; 40(8): 2805–2811.

Kleindorfer

Kissela

Schneider

et al.

Eligibility for recombinant tissue plasminogen activator in acute ischemic stroke: a population-based study. Stroke 2004; 35(2): e27–e29.

Diener

H-C

Lees

Lyden

et al.

NXY-059 for the treatment of acute stroke: pooled analysis of the SAINT I and II trials. Stroke 2008; 39(6): 1751–1758.

Hill

Moy

Palesch

et al.

The albumin in acute stroke trial (ALIAS); design and methodology. Int J Stroke 2007; 2(3): 214–219.

Jauch

Saver

Adams

et al.

Guidelines for the early management of patients with acute ischemic stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association. Stroke 2013; 44(3): 870–947.

Khatri

Kleindorfer

Yeatts

et al.

Strokes with minor symptoms: an exploratory analysis of the National Institute of Neurological Disorders and Stroke recombinant tissue plasminogen activator trials. Stroke 2010; 41(11): 2581–2586.

Messe SR, Khatri P, Reeves MJ, et al. Why are acute ischemic stroke patients not receiving IV tPA?: Results from a national registry. Neurology 2016; 87(15): 1565–1574.

Willey

Khatri

Khoury

et al.

Variability in the use of intravenous thrombolysis for mild stroke: experience across the SPOTRIAS network. J Stroke Cerebrovasc Dis 2013; 22(4): 318–322.

Fischer

Baumgartner

Arnold

et al.

What is a minor stroke?

Stroke 2010; 41(4): 661–666.

10.

Khatri P, Conaway MR, Johnston KC, et al. Ninety-Day outcome rates of a prospective cohort of consecutive mild ischemic stroke patients. Stroke 2012; 43(2): 560–562.

11.

Logallo

Kvistad

Naess

et al.

Mild stroke: safety and outcome in patients receiving thrombolysis. Acta Neuro Scand Suppl 2014; 129(198): 37–40.

12.

Shamy

Pugliese

Meisel

et al.

How patient demographics, imaging, and beliefs influence tissue-type plasminogen activator use: a survey of North American neurologists. Stroke 2016; 47(8): 2051–2057.

13.

Yew

Cheng

. Diagnosis of acute stroke. Am Fam Physician 2015; 91(8): 528–536.

14.

Brunser

Illanes

Lavados

et al.

Exclusion criteria for intravenous thrombolysis in stroke mimics: an observational study. J Stroke Cerebrovasc Dis 2013; 22(7): 1140–1145.

15.

Valle

Lopera

Guillán

et al.

[Stroke mimics: a challenge for the emergency physician]. An Sist Sanit Navar 2014; 37(1): 117–128.

16.

Goyal

Male

Al Wafai

et al.

Cost burden of stroke mimics and transient ischemic attack after intravenous tissue plasminogen activator treatment. J Stroke Cerebrova Dis 2015; 24(4): 828–833.

17.

Liberman

Liotta

Caprio

et al.

Do efforts to decrease door-to-needle time risk increasing stroke mimic treatment rates?

Neurol Clin Pract 2015; 5(3): 247–252.

18.

Nguyen

Chang

. Stroke mimics and acute stroke evaluation: clinical differentiation and complications after intravenous tissue plasminogen activator. J Emerg Med 2015; 49(2): 244–252.

19.

Grimm

DeAngelis

. Intratumoral hemorrhage after thrombolysis in a patient with glioblastoma multiforme. Neurology 2007; 69(9): 936.

20.

Zinkstok

Engelter

Gensicke

et al.

Safety of thrombolysis in stroke mimics: results from a multicenter cohort study. Stroke 2013; 44(4): 1080–1084.

21.

Casaubon

Boulanger

Blacquiere

et al.

Canadian stroke best practice recommendations: hyperacute stroke care guidelines, update 2015. Int J Stroke 2015; 10(6): 924–940.

22.

Srinivasan

Goyal

Al Azri

et al.

State-of-the-art imaging of acute stroke. Radiographics 2006; 26(Suppl 1): S75–S95.

23.

Emmer

. Whole brain CT perfusion in acute anterior circulation ischemia: coverage size matters. Neuroradiology 2014; 56(12): 1121–1126.

24.

van den Wijngaard

. Value of whole brain computed tomography perfusion for predicting outcome after TIA or minor ischemic stroke. J Stroke Cerebrovasc Dis 2015; 24: 2081–2087.

25.

Chakraborty

. Beating the clock: time delays to thrombolytic therapy with advanced imaging and impact of optimized workflow. J Stroke Cerebrovasc Dis 2015; 24(6): 1270–1275.

26.

Kasner

Chalela

Luciano

et al.

Reliability and validity of estimating the NIH stroke scale score from medical records. Stroke 1999; 30(8): 1534–1537.

27.

Sabarudin

Subramaniam

Sun

. Cerebral CT angiography and CT perfusion in acute stroke detection: a systematic review of diagnostic value. Quant Imaging Med Surg 2014; 4(4): 282–290.

28.

Campbell

BCV

Weir

Desmond

et al.

CT perfusion improves diagnostic accuracy and confidence in acute ischaemic stroke. J Neurol Neurosurg Psychiatry 2013; 84(6): 613–618.

29.

Suzuki

et al.

Utility of CT perfusion with 64-row multi-detector CT for acute ischemic brain stroke. Emerg Radiol 2011; 18(2): 95–101.

30.

Kloska

Nabavi

Gaus

et al.

Acute stroke assessment with CT: do we need multimodal evaluation?

Radiology 2004; 233(1): 79–86.

31.

De Cocker

Geerlings

Hartkamp

et al.

Cerebellar infarct patterns: the SMART-Medea study. NeuroImage Clin 2015; 8: 314–321.

32.

Yang

Qin

Zhang

et al.

Infarct size may distinguish the pathogenesis of lacunar infarction of the middle cerebral artery territory. Med Sci Monit 2016; 22: 211–218.

33.

Boas

Fleischmann

. CT artifacts: causes and reduction techniques. Imaging in Med 2012; 4: 229–240.

34.

Wintermark

Smith

et al.

Vasospasm after subarachnoid hemorrhage: utility of perfusion CT and CT angiography on diagnosis and management. AJNR Am J Neuroradiol 2006; 27: 26–34.

35.

Sylaja

Coutts

Krol

et al.

When to expect negative diffusion-weighted images in stroke and transient ischemic attack. Stroke 2008; 39: 1898–1900.

36.

Tassi

et al.

Stroke warning syndrome: 18 new cases. J Neurol Sci 2013; 331(1–2): 168–171.