3 Medical Imaging for Acute Ischemic and Hemorrhagic Stroke

Andrew Pines, Austin Pena, and Brian W. Chong

Abstract

This chapter will provide the reader with an overview of the current guidelines on how to best employ medical imaging modalities in acute stroke care. We will include supporting images, clinical pearls, and tables to compare imaging modalities side by side. We will also summarize the latest research considering current and future applications. First, we will review the use of noncontrast head computed tomography (CT), and important signs to look for in both hemorrhagic and ischemic stroke patients. We will introduce the Alberta Stroke Program Early CT Score (ASPECTS) score and its relevance to evaluating the patient with acute ischemic stroke. We will then discuss the utility of CT angiography and CT perfusion studies. We will review the recent studies that have used novel CT perfusion algorithms to extend the window for endovascular thrombectomy procedures in patients with larger vessel occlusions. Acute stroke evaluation with magnetic resonance imaging will be discussed along with a review of how different institutions employ this technique in the acute stroke setting. The merits and detriments of diffusion-weighted imaging and perfusion-weighted imaging will be contrasted. In the final section of the chapter, we will explain the evidence supporting the use of magnetic resonance angiography in specific scenarios. This chapter will outline the utility of CT and MR imaging in determining treatment in the acute period of stroke management. We will cover the key components of current guidelines in order to provider the reader with a succinct summary of both established practice and the latest research.

Schlüsselwörter

noncontrast head CT - CTA - CTP - ASPECTS - MRA - acute hemorrhagic stroke - acute ischemic stroke

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