Extracellular volume fraction determined by equilibrium contrast-enhanced CT for the prediction of the pathological complete response to neoadjuvant chemoradiotherapy for locally advanced rectal cancer.

Objectives: To determine the extracellular volume (ECV) fraction derived from equilibrium contrast-enhanced CT for predicting pathological complete response (pCR) after neoadjuvant chemoradiotherapy (NCRT) in locally advanced rectal cancer (LARC).

Methods: The ECV fraction before NCRT (ECV and/or ECV after NCRT (ECV) of rectal tumors was assessed, and ECV was calculated as ECV - ECV. The histopathologic tumor regression grading (TRG) was assessed.

Low-dose CT with tin filter combined with iterative metal artefact reduction for guiding lung biopsy.

Background: Computed tomography (CT) is currently the imaging modality of choice for guiding pulmonary percutaneous procedures. The use of a tin filter allows low-energy photons to be absorbed which contribute little to image quality but increases the radiation dose that a patient receives. Iterative metal artefact reduction (iMAR) was developed to diminish metal artefacts.