Response to letter to the editor

Excerpt

We thank the authors for their detailed summary of the role of chemical shift MRI imaging (CS-MRI) in the diagnostic workup of incidentally detected indeterminate adrenal nodules. We agree that CS-MRI may be a useful method of characterizing adrenal masses in patients where iodinated contrast material is a concern (for example history of anaphylactic reaction or severe chronic renal insufficiency) or to avoid radiation exposure (young patients) [1]. As you describe, a recent retrospective review of multiple studies reveals that CS-MRI has a pooled sensitivity of 0.94 and a specificity of 0.95 [2]. However, these data did show considerable heterogeneity with sensitivities ranging from 0.57 to 1.0 and specificities ranging from 0.75 to 1.0 [2]. It is likely that this significant variation in sensitivity and specificity results from including all adrenal nodules, regardless of unenhanced attenuation. We believe that appropriately performed adrenal CT is the best method to assess an indeterminant adrenal nodule for the reasons detailed below. …