The OPTICA study (Optimised Computed Tomography Pulmonary Angiography in Pregnancy Quality and Safety study): Rationale and design of a prospective trial assessing the quality and safety of an optimised CTPA protocol in pregnancy

摘要

Background: CTPA is the gold standard investigation for evaluating suspected pulmonary embolism (PE) in the general population however is sometimes considered second line in pregnant and post-partum patients with a normal CXR due to its higher breast dose and the increased radio-sensitivity of breast tissue during this period. Guidelines advocating for scintigraphy over CTPA, however, quote significantly higher breast doses than those achievable with optimised low dose strategies. Defining the radiation dose achievable with a specific low-dose CTPA protocol is therefore imperative. As decreasing dose is associated with increased image noise, demonstrating the image quality and validity of a negative low-dose CTPA in out-ruling PE in this population is necessary.