SKULL AND BRAIN Scalp, Skull Anatomically Based Differentials Skull Normal Variants Scalp Mass, Child Scalp Mass, Adult Congenital Anomalies of Skull Base Sellar/Parasellar Mass With Skull Base Invasion Generic Imaging Patterns Hair on End Thick Skull, Generalized Thick Skull, Localized Thin Skull, Generalized Thin Skull, Localized Lytic Skull Lesion, Solitary Multiple Lucent Skull Lesions Sclerotic Skull Lesion, Solitary Sclerotic Skull Lesions, Multiple Clinically Based Differentials Macrocephaly Microcephaly Meninges Anatomically Based Differentials Dural Calcification(s) Dural-Based Mass, Solitary Dural-Based Masses, Multiple Falx Lesions Generic Imaging Patterns Thick Dura/Arachnoid, Generalized Pial Enhancement Dural Tail Sign Ventricles, Periventricular Regions Anatomically Based Differentials Ventricles, Normal Variants Choroid Plexus Lesions, Child Choroid Plexus Lesions, Adult Ependymal/Subependymal Lesions Lateral Ventricle Mass Thick Septum Pellucidum Foramen of Monro Mass 3rd Ventricle Mass, Anterior 3rd Ventricle Mass, Body/Posterior Cerebral Aqueduct/Periaqueductal Lesion 4th Ventricle Mass, Child 4th Ventricle Mass, Adult Generic Imaging Patterns Bubbly Appearing Intraventricular Mass Ependymal Enhancement Large Ventricles Small Ventricles Asymmetric Lateral Ventricles Irregular Lateral Ventricles Periventricular Enhancing Lesions Modality-Specific Imaging Findings Intraventricular Calcification(s) Periventricular Calcification(s) Periventricular T2/FLAIR Hyperintense Lesions Extraaxial Spaces and Subarachnoid Cisterns Anatomically Based Differentials Cistern, Subarachnoid Space Normal Variants Epidural Mass Enlarged Sulci, Generalized Effaced Sulci, Generalized Interhemispheric Fissure Cysts CPA Mass, Adult Cystic CPA Mass Prepontine Cistern Mass Ventral Foramen Magnum Mass Dorsal Foramen Magnum Mass Generic Imaging Patterns Solitary Enhancing Cranial Nerve Multiple Enhancing Cranial Nerves CSF-Like Extraaxial Fluid Collection Convexal Subarachnoid Hemorrhage CSF-Like Extraaxial Mass Sulcal/Cisternal Enhancement Fat in Sulci/Cisterns/Ventricles Pneumocephalus Modality-Specific Imaging Findings Extraaxial Flow Voids T1 Hyperintense CSF FLAIR Hyperintense Sulci T2 Hypointense Extraaxial Lesions Hyperdense CSF Hyperdense Extraaxial Mass(es) Hypodense Extraaxial Mass(es) Brain Parenchyma, General Generic Imaging Patterns Multiple Enhancing Lesions, General Ring-Enhancing Lesion, Solitary Ring-Enhancing Lesion, Multiple Solitary Cystic Parenchymal Mass, General CSF-Like Parenchymal Lesion(s) Cyst With Nodule Fat and Fat-Like Lesion(s) Modality-Specific Imaging Findings Solitary Parenchymal Calcification Multiple Parenchymal Calcifications Solitary Hyperdense Parenchymal Lesion Multiple Hyperdense Parenchymal Lesions Solitary Hypodense Parenchymal Lesion Multiple Hypodense Parenchymal Lesions Multiple Brain Hyperintensities (T2/FLAIR), Common Multiple Brain Hyperintensities (T2/FLAIR), Less Common Multiple Brain Hyperintensities (T2/FLAIR), Rare but Important Multiple Hypointense Foci on T2 Multiple Hypointense Foci on GRE/SWI T1/T2 Hyperintense Parenchymal Lesions T1 Hypointense, T2 Hyperintense Parenchymal Lesions T1/T2 Isointense Parenchymal Lesions Restricted Diffusion, General Restricted Diffusion, Cortex Restricted Diffusion, Basal Ganglia T1 Hyperintense Parenchymal Lesion(s) Clinically Based Differentials Brain Tumor in Newborn/Infant Brain Tumor in Child 1 Year Epilepsy, Child Epilepsy, Adult Supratentorial Brain Parenchyma Anatomically Based Differentials Asymmetric Cerebral Hemispheres Thick Cortex Thin Cortex Focal Cortical Mass sakriti opis