The use of contrast-enhanced, time-resolved magnetic resonance angiography in cerebrovascular pathology

Digital subtraction angiography (DSA) has long been the imaging gold standard in the evaluation, treatment, and follow-up of cerebro- and spinovascular disorders. However, DSA has the disadvantages of invasiveness, contrast allergy or nephropathy, the impracticality of procedural preparation and recovery, and expense. Contrast-enhanced (CE), time-resolved (TR) magnetic resonance angiography (CE TR-MRA) is a sophisticated, relatively novel imaging modality that provides multiphasic contrast-enhanced visualization of the neurovasculature. Given the crucial role of angiography in all aspects of care for patients with complex neurovascular disorders, it is incumbent on those who care for these patients to understand the usefulness and pitfalls of novel imaging in this arena to ensure best practices, and to deliver cutting edge care to these patients in a way that minimizes cost, but does not compromise quality. CE TR-MRA has the potential to play an expanded role in the workup and follow-up across the spectrum of neurovascular disease, and this review is aimed to help neurosurgeons better understand how CE TR-MRA can be used to better manage patients in this cohort.

P6529Safety of emergency pretreatment regimen for contrast allergy before percutaneous coronary intervention for ST-elevation myocardial infarction

Background Primary percutaneous coronary intervention (PPCI) is the best treatment for ST-elevation myocardial infarction (STEMI). However, patients with prior contrast reactions may not receive PCI due to concern over a recurrent contrast reaction. Purpose To determine the clinical efficacy of emergency pretreatment regimens for contrast allergy in STEMI patients undergoing PPCI. Methods We retrospectively identified all individuals with a history of contrast allergy who presented with STEMI, were pretreated for contrast allergy, and underwent PPCI at our medical center between January 2005 to May 2018. Emergency pretreatment regimen included a combination of intravenous (IV) steroid, IV famotidine and IV diphenhydramine administered immediately before PCI. Laboratory records, inpatient notes, and discharge summaries were reviewed to confirm the severity of the original contrast allergy and identify any allergic breakthrough reaction after pretreatment with an emergency regimen. Reactions were characterized as mild, moderate, severe, or of unknown severity. Results During the study period 15,712 individuals underwent PCI, of which 176 patients presented with STEMI, had confirmed contrast allergy, and were pretreated before undergoing PCI. No patient with a history of contrast allergy underwent PPCI without pre-treatment. Mean age was 64 years, with 52% males, and all individuals were white. The majority had hypertension (77%), 67% had dyslipidemia, 29% had diabetes mellitus, and 20% patients had a prior history of MI. Intravenous steroids used in the emergency regimen included methylprednisone (n=100), hydrocortisone (n=70), and dexamethasone (n=6). The original allergic response to ICM was mild in 59% patients, moderate in 15%, severe in 20% and of unknown severity in 13% patients. Of the 176 patients only 10 (5.6%) developed a breakthrough reaction. Most of which were mild; none was fatal. Median length of hospital stays was three days and nine patients (10.8%) passed away within 30 days of hospital admission. Conclusions Patients with prior contrast allergy presenting with STEMI can safely undergo PPCI after emergency pretreatment. Breakthrough reactions are infrequent and mild.