E1882. Diagnostic Yield of Non-Contrast Brain and Pituitary MRI for Pediatric Patients with Selected Pathologies
  1. Jennifer Huang; Vanderbilt University
  2. Asha Sarma; Vanderbilt University
  3. Sumit Pruthi; Vanderbilt University
Pre- and post-contrast brain and pituitary Magnetic Resonance Imaging (MRI) is the standard of care for pediatric pituitary pathologies. In our practice, central precocious puberty (CPP), growth hormone deficiency (GHD), and short stature (SS) are common indications. Evidence and our experience suggest that the most common anatomic etiologies (small pituitary size or ectopic/absent neurohypophysis) can be detected without contrast-enhanced sequences in most cases. This study evaluates the diagnostic yield of non-contrast only MRI in this patient population. The ultimate goal is to determine whether this protocol can be safely applied in order to decrease scan time, potential exposure to anesthesia and gadolinium, and cost.

Materials and Methods:
Retrospective review of pituitary MRI studies obtained from 2010-2019 for CPP, GHD, or SS in patients =18 years was performed. Blinded review of non-contrast images was performed by two subspecialty-trained pediatric neuroradiologists.

Data from 448 MRI studies obtained for CPP (35%), GHD (49%), or SS (16%) were analyzed. Mean age was 8.2 years (range 9 months to 17 years). 226 (50%) studies required sedation, and 448 (100%) were performed with gadolinium contrast. Of the 136 (30%) abnormal studies, there was 71% concordance (n=97) with original reports on blinded review of non-contrast images. Of the 39 discrepancies, 79% (n=31) were of no clinical significance (e.g., pars intermedia cyst) and 1 was of uncertain significance. The remaining 7 of the 39 (18%) were visible on non-contrast images but required contrast for definitive characterization: 5 were extrasellar masses and 2 were pituitary stalk abnormalities.

Most pathologies causing CPP, GHD, or SS can be diagnosed on non-contrast sequences. Microadenomas, a common justification for contrast administration, may not influence management in this patient population. Minimal inconvenience would be added for the few patients who would need to return for contrast-enhanced MRI for definitive diagnosis. Moreover, in a large majority of patients, the shorter non-contrast examination would provide savings in time, anesthesia, gadolinium, and associated costs. Clinical Relevance Truncated, non-contrast pituitary MRI for central precocious puberty, growth hormone deficiency, and short stature has similar diagnostic yield compared to the standard contrast-enhanced protocol.