Stroke protocol (MRI)

Last revised by Amanda Er on 19 Aug 2023

Citation, DOI, disclosures and article data

Citation:

Di Muzio B, Er A, Murphy A, et al. Stroke protocol (MRI). Reference article, Radiopaedia.org (Accessed on 24 Apr 2024) https://doi.org/10.53347/rID-37793

DOI:

https://doi.org/10.53347/rID-37793

Permalink:

https://radiopaedia.org/articles/37793

rID:

37793

Article created:

23 Jun 2015, Bruno Di Muzio ◉ ◈

Disclosures:

At the time the article was created Bruno Di Muzio had no recorded disclosures.

View Bruno Di Muzio's current disclosures

Last revised:

19 Aug 2023, Amanda Er ◉

Disclosures:

At the time the article was last revised Amanda Er had no financial relationships to ineligible companies to disclose.

View Amanda Er's current disclosures

Revisions:

10 times, by 9 contributors - see full revision history and disclosures

Systems:

Central Nervous System

Tags:

mri protocol, cns protocol

Synonyms:

MRI protocol for stroke assessment

MRI protocol for stroke assessment is a group of MRI sequences put together to best approach brain ischemia.

CT is still the choice as the first imaging modality in acute stroke institutional protocols, not only because the availability and the easy and fast access to a CT scanner, but also due the better sensitivity for intracerebral hemorrhage (ICH) diagnosis ¹. Some institutions also apply a quick MRI stroke protocol for code stroke patients assessment within the narrow time window for thrombolytic therapy.

Note: This article is intended to outline some general principles of protocol design. The specifics will vary depending on MRI hardware and software, radiologist's and referrer's preference, institutional protocols, patient factors (e.g. allergy) and time constraints.

Sequences

A good protocol involves at least:

T1 weighted
- plane: sagittal (or volumetric 3D)
- sequence: fast-spin echo (T1 FSE) or gradient (e.g. T1 MPRAGE)
- purpose: an anatomical evaluation. Cortical laminar necrosis or pseudolaminar necrosis may be seen as a ribbon of intrinsic high T1 signal, usually after 2 weeks (although it can be seen earlier) ²
T2 weighted
- plane: axial
- sequence: T2 FSE
- purpose:
  - loss of normal signal void in large arteries may be visible immediately
  - after 6-12 hours infarcted tissue becomes high signal ²
  - sulcal effacement and mass effect develop and become maximal in the first few days

FLAIR
- plane: axial
- sequence: FLAIR
- purpose:
  - after 6-12 hours infarcted tissue becomes high signal ²
  - sulcal effacement and mass effect develop and become maximal in the first few days
diffusion-weighted imaging (DWI)
- plane: axial
- sequence: DWI: B=0, B=1000 and ADC
- purpose:
  - early identification of ischemic stroke: diffusion restriction may be seen within minutes following the onset of ischemia ³
  - correlates well with infarct core
  - differentiation of acute from chronic stroke
susceptibility-weighted imaging (SWI)
- plane: axial
- sequence: susceptibility weighted imaging (ideal) or T2*
- purpose: highly sensitive in the detection of hemorrhage

MR angiography (MRA)
- plane: axial with reconstructions
- sequence: time of flight angiography
- purpose: assess for luminal diameter and occlusions