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Low dose CT perfusion in acute ischemic stroke

  • Diagnostic Neuroradiology
  • Published:
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Abstract

Introduction

The purpose of this investigation is to determine if CT perfusion (CTP) measurements at low doses (LD = 20 or 50 mAs) are similar to those obtained at regular doses (RD = 100 mAs), with and without the addition of adaptive statistical iterative reconstruction (ASIR).

Methods

A single-center, prospective study was performed in patients with acute ischemic stroke (n = 37; 54 % male; age = 74 ± 15 years). Two CTP scans were performed on each subject: one at 100 mAs (RD) and one at either 50 or 20 mAs (LD). CTP parameters were compared between the RD and LD scans in regions of ischemia, infarction, and normal tissue. Differences were determined using a within-subjects ANOVA (p < 0.05) followed by a paired t test post hoc analysis (p < 0.01).

Results

At 50 mAs, there was no significant difference between cerebral blood flow (CBF), cerebral blood volume (CBV), or time to maximum enhancement (Tmax) values for the RD and LD scans in the ischemic, infarcted, or normal contralateral regions (p < 0.05). At 20 mAs, there were significant differences between the RD and LD scans for all parameters in the ischemic and normal tissue regions (p > 0.05).

Conclusion

CTP-derived CBF and CBV are not different at 50 mAs compared to 100 mAs, even without the addition of ASIR. Current CTP protocols can be modified to reduce the effective dose by 50 % without altering CTP measurements.

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Ethical standards and patient consent

We declare that all human and animal studies have been approved by the St. Michael’s Hospital Research Ethics Board and have therefore been performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments. We declare that all patients gave informed consent prior to inclusion in this study.

Conflict of interest

T-YL licenses CT Perfusion software to, and receives research funding from, GE Healthcare.

Author information

Authors and Affiliations

  1. Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Room AG 31, Toronto, ON, M4N 3M5, Canada

    Amanda Murphy, Sean Symons, Raphael Jakubovic, Liying Zhang & Richard I. Aviv

  2. Robarts Research Institute, London, Ontario, Canada

    Aaron So & Ting-Yim Lee

Authors
  1. Amanda Murphy
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  2. Aaron So
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  3. Ting-Yim Lee
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  4. Sean Symons
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  5. Raphael Jakubovic
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  6. Liying Zhang
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  7. Richard I. Aviv
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Correspondence to Amanda Murphy.

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Murphy, A., So, A., Lee, TY. et al. Low dose CT perfusion in acute ischemic stroke. Neuroradiology 56, 1055–1062 (2014). https://doi.org/10.1007/s00234-014-1434-z

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  • DOI: https://doi.org/10.1007/s00234-014-1434-z

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