Original Article
Copyright ©2013 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Radiol. Apr 28, 2013; 5(4): 156-165
Published online Apr 28, 2013. doi: 10.4329/wjr.v5.i4.156
Asymmetrically hypointense veins on T2*w imaging and susceptibility-weighted imaging in ischemic stroke
Ulf Jensen-Kondering, Ruwen Böhm
Ulf Jensen-Kondering, Institute of Neuroradiology, University of Schleswig-Holstein, Campus Kiel, 24105 Kiel, Germany
Ruwen Böhm, Institute of Experimental and Clinical Pharmacology, University of Schleswig-Holstein, Campus Kiel, 24105 Kiel, Germany
Author contributions: Jensen-Kondering U and Böhm R performed the literature research, analyzed the data, and wrote and revised the paper.
Correspondence to: Dr. Ulf Jensen-Kondering, MD, Institute of Neuroradiology, University of Schleswig-Holstein, Campus Kiel, Haus 41, Arnold-Heller-Str. 3, Haus 41, 24105 Kiel, Germany. ulfrjensen@web.de
Telephone: +49-431-5974806 Fax: +49-431-5974913
Received: December 19, 2012
Revised: February 8, 2013
Accepted: March 6, 2013
Published online: April 28, 2013
Abstract

AIM: To review the literature on the assessment of venous vessels to estimate the penumbra on T2*w imaging and susceptibility-weighted imaging (SWI).

METHODS: Literature that reported on the assessment of penumbra by T2*w imaging or SWI and used a validation method was included. PubMed and relevant stroke and magnetic resonance imaging (MRI) related conference abstracts were searched. Abstracts that had overlapping content with full text articles were excluded. The retrieved literature was scanned for further relevant references. Only clinical literature published in English was considered, patients with Moya-Moya syndrome were disregarded. Data is given as cumulative absolute and relative values, ranges are given where appropriate.

RESULTS: Forty-three publications including 1145 patients could be identified. T2*w imaging was used in 16 publications (627 patients), SWI in 26 publications (453 patients). Only one publication used both (65 patients). The cumulative presence of hypointense vessel sign was 54% (range 32%-100%) for T2* (668 patients) and 81% (range 34%-100%) for SWI (334 patients). There was rare mentioning of interrater agreement (6 publications, 210 patients) and reliability (1 publication, 20 patients) but the numbers reported ranged from good to excellent. In most publications (n = 22) perfusion MRI was used as a validation method (617 patients). More patients were scanned in the subacute than in the acute phase (596 patients vs 320 patients). Clinical outcome was reported in 13 publications (521 patients) but was not consistent.

CONCLUSION: The low presence of vessels signs on T2*w imaging makes SWI much more promising. More research is needed to obtain formal validation and quantification.

Keywords: Acute ischemic stroke, Oxygen extraction fraction, Susceptibility-weighted imaging, T2*, Penumbra

Core tip: Thrombolytic therapy with intravenous tissue plasminogen activator is the only approved therapy for acute ischemic stroke. The detection of hypointense venous vessels with blood oxygenation level dependent (BOLD) imaging to assess the amount of penumbral tissue in acute ischemic stroke has emerged as a little noticed alternative imaging technique. In the present state the combined use of perfusion and BOLD imaging would provide further complementary information to help visualize and understand the role of the ischemic penumbra.