title: Validation of co-registration of clinical lung ventilation and perfusion SPECT.
abstract: Ventilation (V) and perfusion (Q) image data from 20 patients undergoing a routine clinical SPECT V/Q study were aligned via rigid coregistration using intrinsic image intensity values with the software package 'Qonsub'. Accuracy of the coregistration was quantified by an independent technique that used Tc-99m filled fiducial markers which had been adhered to the patient's skin prior to imaging. These were visible on both the V and Q scans, but were removed from the images for the coregistration step. The level of inter-marker displacement between scans was monitored to ensure it did not invalidate the assessment of coregistration accuracy. Once coregistered, results showed that for 65% of patients in the survey co-registration accuracy was better than 1 pixel (3.8 mm), 30% were co-registered with an accuracy of between 1 and 2 pixels and 5% were co-registered with an accuracy of between 2 and 3 pixels.
authors.affiliation: Department of Medical Physics and Bioengineering, Christchurch Hospital, Riccarton Avenue, Private Bag, 4710, Christchurch, New Zealand. steven.marsh@cdhb.govt.nz
authors.forename: Steven
authors.initials: S
authors.lastname: Marsh
authors.forename: Leighton
authors.initials: L
authors.lastname: Barnden
authors.forename: Darin
authors.initials: D
authors.lastname: O'Keeffe
mesh_terms: D000465:Algorithms; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D010363:Pattern Recognition, Automated / Q000379:methods*; D055420:Perfusion Imaging / Q000379:methods*; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging*; D012123:Pulmonary Ventilation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*