Prostate cancer GTV delineation with biparametric MRI and Ga-PSMA-PET: comparison of expert contours and semi-automated methods.

Objective: The optimal method for delineation of dominant intraprostatic lesions (DIL) for targeted radiotherapy dose escalation is unclear. This study evaluated interobserver and intermodality variability of delineations on biparametric MRI (bpMRI), consisting of weighted (W) and diffusion-weighted (DWI) sequences, and Ga-PSMA-PET/CT; and compared manually delineated GTV contours with semi-automated segmentations based on quantitative thresholding of intraprostatic apparent diffusion coefficient (ADC) and standardised uptake values (SUV).

Methods: 16 patients who had bpMRI and PSMA-PET scanning performed prior to any treatment were eligible for inclusion.

Magnetic resonance angiography or digital subtraction catheter angiography for follow-up of coiled aneurysms: do we need both?

Introduction: Endovascular treatment of intracranial aneurysms is now common. Digital subtraction catheter angiography (DSA) is the gold standard for imaging follow-up of coiled intracranial aneurysms; however, it is an invasive procedure with a risk of complications. Time-of-flight magnetic resonance angiography (MRA) is an alternative non-invasive imaging method.