Patient- and Examination-Related Predictors of 3D MRCP Image Quality in Children

BACKGROUND. MRCP provides noninvasive imaging of the biliary tree and pancreatic duct. In our experience, MRCP image quality is commonly suboptimal in children. OBJECTIVE. The purpose of this study was to characterize the frequency of nondi-agnostic 3D fast spin-echo (FSE) MRCP acquisitions and determine predictors of nondi-agnostic MRCP image quality in children. METHODS. This retrospective study included 200 randomly selected pediatric patients (101 female and 99 male patients; mean age, 11.7 years) who underwent MRCP between January 1, 2019, and December 31, 2020. Patient- and examination-related variables were recorded. Three fellowship-trained pediatric radiologists independently reviewed 3D FSE MRCP acquisitions for diagnostic quality (diagnostic vs nondiagnostic) and overall image quality score on a scale from 1 to 5 (1 = worst image quality imaginable, 5 = best image quality imaginable). After computing interreader agreement, analyses used readers' most common diagnostic quality assessment and mean image quality score. Multivariable logistic regression and linear regression analyses were used to identify predictor variables of a diagnostic examination and higher image quality score. RESULTS. Interreader agreement for an MRCP acquisition being diagnostic quality, expressed as a kappa coefficient, was 0.53-0.71; interreader agreement for image quality score, expressed as an intraclass correlation coefficient, was 0.68-0.74. A total of 36 of 200 (18%) MRCP acquisitions were nondiagnostic; the mean image quality score was 3.5 ± 1.1 (SD). Multivariable predictors of a diagnostic MRCP acquisition included greater body mass index (OR = 1.11 [95% CI, 1.02-1.21]; p = .02), scanner field strength of 1.5 T (odds ratio [OR] = 2.87 [95% CI, 1.23-6.68]; p = .01), and presence of acute pancreatitis (OR = 4.91 [95% CI, 1.53-15.77]; p = .008). Multivariable predictors of a higher image quality score (β = 0.05-0.94) included older age (p = .01), imaging performed with patient under sedation or general anesthesia (p < .001), presence of biliary dilatation (p = .004), and inpatient status (p = .02). A lower image quality score was predicted by a scanner field strength of 3 T (β = -0.61; p < .001). A greater amount of time between the start of the MRI examination and the MRCP acquisition exhibited a nonsignificant association with a decrease in the image quality score (p = .06). CONCLUSION. Pediatric MRCP acquisitions are commonly nondiagnostic. Patient-specific and technical factors systematically impact MRCP image quality in children. CLINICAL IMPACT. Recognition of image quality predictors that are potentially modifiable and amendable to proactive intervention can guide efforts to optimize MRCP image quality in children.