Fig 7.

Random forest variable importance plot. This graphic shows the importance (x-axis) of each evaluated prenatal MR imaging finding (y-axis) with respect to the diagnosis of CAS. The independent contribution of each prenatal finding was estimated as the error of CAS classification by the machine-learning algorithm compared with the error that results when that finding is negated. The most important imaging findings associated with an accurate diagnosis of CAS are highlighted in red. Dominant findings include enlargement of the third ventricle inferior recesses, size of the lateral and third ventricles (especially enlargement of the smaller lateral ventricle), and an abnormally thin and/or dysgenetic corpus callosum. AS indicates aqueductal stenosis.