Although CT angiography (CTA) has demonstrated its efficacy as a non-invasive clinical alternative to cardiac angiography, there have been few studies examining its utility in the evaluation of peripheral arterial occlusive disease (PAOD). According to recent research published in the American Journal of Roentgenology, CTA should be used in the management of PAOD.
“The diagnostic standard for the evaluation of PAOD is digital subtraction angiography, even though this technique has several disadvantages such as invasiveness and high cost,” the authors wrote.
Researchers from the department of cardiovascular and interventional radiology at the Medical University of Vienna in Austria, conducted a retrospective analysis of clinical outcome among patients referred to the facility to undergo CTA for the evaluation of intermittent claudication from January 2003 to February 2004.
The study population consisted of 58 consecutively enrolled patients with known or clinically suspected PAOD. The group, 42 men and 16 women with a mean age of 65 years, underwent a CTA of the abdominal aorta and runoff vessels. The CTA studies were performed on a 16-slice Siemens Medical Solutions CT system (Somatom Sensation 16).
The findings of the peripheral artery CTA exams were used as the basis for treatment decisions and treatment planning.
Images obtained from the exam underwent post-processing including maximum intensity projections (MIPs), multipath curved planar reformations (CPRs), and two variants of CPRs.
“The variants were 3-mm projected CPRs (thick CPRs) and unit-thickness stretched CPRs with a virtual gauging catheter (thin CPRs),” the researchers noted.
The CTA images were interpreted on an Agfa Healthcare PACS (Impax) workstation by a final year radiology resident, and then were reviewed by a staff radiologist with more than five years experience in vascular imaging. Treatment decisions were made in consensus during a routine interdisciplinary vascular conference, attended by interventional radiologists, vascular surgeons, and vascular medicine physicians.
“The disease-specific patient histories showed a broad spectrum of pathologic conditions, including multiple previous endovascular treatments and surgical interventions and formerly untreated vascular disease,” the researchers observed.
Based on the findings from the peripheral artery CTA exams, 18 patients were referred for endovascular treatment, nine were referred for surgery, and two patients received combined endovascular and surgical treatment. On the basis of their CTA studies, the remaining 29 patients received conservative treatment.
In follow-up exams (ultrasound, additional CTA, and MR angiography) independent of the findings of the baseline CTAs, 18 of the 29 treated patients had no additional findings, confirming the diagnosis of the baseline CTA. The remaining 11 patients presented with clinical progression of their disease and underwent further treatment.
“The results of this analysis of treatment decisions based on findings on CT angiographic examinations performed in a clinical setting indicate that CTA can provide all the information needed for the triage and clinical care of patients with stage IIb (the entry point for interventional or surgical treatment) PAOD,” the authors wrote.