Comparison of image quality between filtered back-projection and the adaptive statistical and novel model-based iterative reconstruction techniques in abdominal CT for renal calculi.

Objectives: To compare image quality on computed tomographic (CT) images acquired with filtered back-projection (FBP), adaptive statistical iterative reconstruction (ASIR) and model-based iterative reconstruction (MBIR) techniques in CT kidney/ureter/bladder (KUB) examination.

Methods: Eighteen patients underwent standard protocol CT KUB at our institution. The same raw data were reconstructed using FBP, ASIR and MBIR.

Usual and unusual causes of splaying of the carotid artery bifurcation: the Lyre sign--a pictorial review.

The 'Lyre' sign describes the characteristic splaying of the carotid artery bifurcation due to a carotid body tumour (paraganglioma) on conventional carotid angiography. In this pictorial review, we describe and illustrate two cases demonstrating the equivalent Lyre sign on multi-detector computed tomography (MDCT) and ultrasound resulting from carotid body tumour and extra-cranial internal carotid artery pseudoaneurysm. Both of these pathologies can manifest acutely and warrant accurate diagnosis to prevent potential catastrophic consequences.