Prosthetic vascular graft infection imaging.

Clinical imaging

PubMedID: 23465974

Khaja MS, Sildiroglu O, Hagspiel K, Rehm PK, Cherry KJ, Turba UC. Prosthetic vascular graft infection imaging. Clin Imaging. 2013;37(2):239-44.
PURPOSE
We are reporting our experience with imaging of vascular graft infections using computed tomography angiography (CTA), white blood cell (WBC) scintigraphy and software-based fusion imaging.

MATERIAL AND METHODS
Institutional review board approval was obtained. We performed a retrospective review of patients who had clinical signs and symptoms of vascular graft infection in whom both WBC single photon emission computed tomography (SPECT) and CTA was performed between 2005 and 2010. We performed fusion imaging with available data using software coregistration technique and analyzed outcome of the patients.

RESULTS
We had 20 patients; 11 had grafts of the aorta, five had peripheral vascular grafts, three had aortic and peripheral vascular grafts, and one had a thoracic aortic graft. WBC imaging was positive in 10 patients, negative in six patients and indeterminate in 4 patients. CTA was positive in six patients, negative in four patients and indeterminate in 10 patients. Sensitivity, specificity, accuracy, positive predictive value and negative predictive value (NPV) for WBC, CTA and WBC SPECT/CTA fusion were 75/100/80/100/50%, 88/50/80/88/50% and 94/50/85/88/67% respectively.

CONCLUSION
The use of CTA, WBC scintigraphy, and image co-registration influenced the diagnostic confidence of graft infection and the outcome of the patients. Software-based fusion imaging of both modalities resulted in improved sensitivity, accuracy, and NPV.