Contrast enhanced pulmonary magnetic resonance angiography for pulmonary embolism: Building a successful program

Abstract

The performance of contrast enhanced pulmonary magnetic resonance angiography (MRA) for the diagnosis of pulmonary embolism (PE) is an effective non-ionizing alternative to contrast enhanced computed tomography and nuclear medicine ventilation/perfusion scanning. However, the technical success of these exams is very dependent on careful attention to the details of the MRA acquisition protocol and requires reader familiarity with MRI and its artifacts. Most practicing radiologists are very comfortable with the performance and interpretation of computed tomographic angiography (CTA) performed to detect pulmonary embolism but not all are as comfortable with the use of MRA in this setting. The purpose of this review is to provide the general radiologist with the tools necessary to build a successful pulmonary embolism MRA program. This review will cover in detail image acquisition, image interpretation, and some key elements of outreach that help to frame the role of MRA to consulting clinicians and hospital administrators. It is our aim that this resource will help build successful clinical pulmonary embolism MRA programs that are well received by patients and physicians, reduce the burden of medical imaging radiation, and maintain good patient outcomes.

Magnetic resonance angiography for the primary diagnosis of pulmonary embolism: A review from the international workshop for pulmonary functional imaging

“…We currently recommend injection of 0.1 mmol/kg of GBCA diluted to a total volume of 30 mL with saline injected at 1.5 mL/s at end-expiration[ 2 , 76 ]. The total length of time for the bolus administration of contrast material is important.…”

“…The Maki artifact[ 77 ] can also simulate a PE. This error in image interpretation is avoidable by using multiple contrast phases and extending the bolus so that contrast is always flowing into the pulmonary arteries during the first acquisition (Figure 3 )[ 76 ].…”

Value of MRI in medicine: More than just another test?

“…Currently, CT angiography (CTA) is the reference standard for the diagnosis of PE . Recently, Nagle et al described the use of pulmonary MRA as an alternative to CTA in young patients presenting to the Emergency Department with clinical suspicion for PE . In this approach a rapid MRA protocol, which took less than 10 minutes, was demonstrated to be a safe and viable alternative to CTA for the diagnosis and exclusion of PE, without the need for ionizing radiation (Fig.…”

Diagnosis of Deep Venous Thrombosis and Pulmonary Embolism

“…82,83 However, single center experiences appear promising that with appropriate tools, training and program-focused approach, MRI can be used for this purpose. 84 …”