Vincent R Spano BMedSc, Presenter: Nothing to Disclose

Daniel Michael Mandell MD, Abstract Co-Author: Nothing to Disclose

Joseph A. Fisher MD, Abstract Co-Author: Stockholder, Thornhill Research Inc

Julien Poublanc MSc, Abstract Co-Author: Nothing to Disclose

Adrian P Crawley PhD, Abstract Co-Author: Nothing to Disclose

David John Mikulis MD, Abstract Co-Author: Stockholder, Thornhill Research Inc

The objective of this study was to evaluate the safety and success rate of mapping cerebrovascular reactivity (CVR) in a clinical population using a precise, prospectively targeted carbon dioxide stimulus and blood-oxygen level dependent MRI (BOLD-MRI).

A database of patient demographics and CVR study details was reviewed for 434 consecutive CVR studies conducted at a tertiary care centre between January 1st, 2006 and December 1st, 2010. Incidence of clinical events during CVR studies was calculated, and total number of failed exams and reasons for failure were ascertained. Using predetermined criteria, CVR map quality was graded on a 3 point scale: 1) good quality 2) diagnostic but suboptimal 3) non-diagnostic.

There were 434 consecutive CVR studies involving 294 patients. Average patient age was 45.9 ± 20.6 years (range: 9 - 88 years), and 51.8% were female. Transient minor symptoms (eg. shortness of breath, headache, dizziness) were reported in 11.1% of studies. There were no transient ischemic attacks, strokes, myocardial infarctions or other major events. Overall success rate in generating CVR maps was 83.9%. There were 70 failed exams in total, due to uncomfortable symptoms (35.7%), excessive head motion (11.4%), noncompliance (2.9%), technical difficulties (10%), and unknown/missing data (40%). In the remaining 364 exams, good quality CVR maps were obtained in 93.4%, diagnostic but suboptimal maps in 3.3%, and non-diagnostic maps in 3.3%.

Cerebrovascular reactivity mapping using a prospectively-targeted carbon dioxide stimulus and BOLD-MRI is a safe and successful investigative tool in a clinical patient population.

The demonstrated safety, tolerability, and success of CO2 BOLD MRI mapping of cerebrovascular reserve establishes the feasibility of using this diagnostic technique in a clinical population.

Spano, V, Mandell, D, Fisher, J, Poublanc, J, Crawley, A, Mikulis, D, Feasibility of CO2 BOLD MRI Mapping of Cerebrovascular Reserve in a Clinical Population: Safety, Quality, and Patient Tolerance.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11001686.html