Detection and follow-up of important extra-arterial lesions with helical CT angiography

AIM: To determine the prevalence and significance of extra-arterial finding s detected prospectively on helical computed tomographic angiography (CTA). SUBJECTS AND METHODS: The official reports of 802 consecutive CTAs performe d over a 4.5-year period on 624 patients and the reports of all radiographi c follow-up studies were reviewed for identification of important extra-art erial findings. Medical records and imaging studies of all patients with pr eviously unknown extra-arterial findings on CTA were reviewed to assess fol low-up. In cases where follow-up was not indicated in the medical record, r eferring physicians were contacted directly. RESULTS: Important, previously unknown, extra-arterial findings were detect ed on 35 CTAs (4.4% of all CTAs, 5.6% of all patients), with 33 of 35 detec ted prospectively. Six lesions were consistent with and/or proven to be mal ignant. Important non-tumoural lesions were discovered on nine CTAs, Of 13 lesions with imaging features that were suspicious for malignancy. Five of these lesions proved to be benign, but radiographic and/or clinical follow- up was not obtained or could not be documented in eight patients. CONCLUSION: With the increasing use of CTA as a replacement for conventiona l angiography. careful attention should be paid to the visualized extra-art erial structures. Extra-vascular findings that are believed to be significa nt, may not be adequately followed-up by referring vascular specialists.