Aaron Charles Miracle BS, Presenter: Nothing to Disclose

Ario Rezaei MD, Abstract Co-Author: Nothing to Disclose

Dheeraj Gandhi MBBS, MD, Abstract Co-Author: Nothing to Disclose

Suresh K. Mukherji MD, Abstract Co-Author: Consultant, Koninklijke Philips Electronics NV Consultant, General Electric Company

Whether the internal carotid (ICA) or external carotid (ECA) should be used to generate arterial reference curves in perfusion computed tomography (CTP) studies of the head and neck remains unclear. This study compares perfusion parameters obtained with ICA versus ECA reference in CTP studies of patients with head and neck squamous cell carcinomas (HNSCCAs).

Fourteen patients with untreated HNSCCA of the upper aerodigestive tract underwent CT scans of the neck along with deconvolution-based CTP imaging through their primary tumor site. Parametric maps of tumor blood volume (BV), fractional tissue blood flow (BF), mean transit time (MTT) and capillary permeability surface area product (PS) were generated by one head and neck radiologist utilizing the ICA and then the ECA as arterial reference. Average values of BV, BF, MTT, and PS for regions of interest (ROIs) placed over the primary tumor site were compared for the two different reference functions. Statistical analysis with linear regression and Pearson correlation coefficients was implemented.

There was highly significant correlation between the values of BF (r = 0.95, p<0.001), BV (r = 0.98, p<0.001), and MTT (r = 0.85, p<0.001) obtained using ICA reference when compared to ECA. PS was also demonstrated to be correlated (r = 0.76, p = 0.0065) between the two reference arteries although not as highly as the other perfusion parameter values.

There is no significant difference in perfusion parameters generated from ICA as compared to ECA reference functions, supporting the use of ICA arterial reference in CTP studies of HNSCCAs.

Evidence supporting the use of ICA instead of ECA reference provides methodologic validity for the current CT perfusion technique used in functional head and neck studies.

Miracle, A, Rezaei, A, Gandhi, D, Mukherji, S, ICA versus ECA Reference in CT Perfusion Studies of the Head and Neck.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8002956.html