Atlas of Normal Imaging Variations of the Brain, Skull, and Craniocervical Vasculature

Alexander M. McKinney, MD, Department of Radiology, University of Minnesota, Minneapolis, MN, USA

Part I: Brain.- Brain Introduction.- Cerebellar Tonsillar Ectopia.- Cerebellar Flocculus Pseudomass.- Mega Cisterna Magna and Retrocerebellar Arachnoid Cysts.- Cranial Nerve VII: Normal Contrast Enhancement on Magnetic Resonance Imaging.- Meckel Cave Prominence, Asymmetry, and Petrous Apex Cephaloceles.- Cavernous Sinus Fat.- Pituitary Variations, Artifacts, Primary Empty Sella, and Incidentalomas.- Liliequist Membrane.- Pineal Gland: Normal Size, Appearance, and Enhancement.- Choroid Plexus: Normal Locations and Appearances.- Hippocampi, Caudate Tail, and Ependymal Variants.- Midline Variants of the Septum Pellucidum, Corpus Callosum, and Massa Intermedia.- Dilated Perivascular Spaces.- Enlargement or Asymmetry of the Lateral Ventricles Simulating Hydrocephalus.- Cerebral or Cerebellar Volume Loss Simulating Subdural Hematomas, Hygromas, and Arachnoid Cysts.- Dural Calcifications: Normal Locations and Appearances.- Pseudo-leptomeningeal Contrast Enhancement.- Basal Ganglia: Physiologic Calcifications.- Susceptibility-Weighted Imaging: Concepts, Basal Ganglia Variations, and Artifacts.- Slow-Flow, Asymptomatic Vascular Malformations: Brain Capillary Telangiectasias and Developmental Venous Anomalies.- Brain MRI Pseudolesions: 3.0T Imaging, FLAIR, and Diffusion-Weighted Imaging.- Pediatric Brain: Normal Variations in Development, Maturation, and Myelination.- Part II: Skull.- Skull: Introduction.- Pediatric Skull: Normal Pediatric Sutures on Computed Tomography.- Skull Base Foramina: Normal Variations and Developmental Defects.- Normal Variations and Developmental Anatomy of the Calvarial Sutures and Fontanelles Above the Skull Base.- Emissary Veins, Vascular-Containing Foramina, and Vascular Depressions of the Skull.- Normal Variations in Calvarial Contour, Irregular Ossification/Aeration, and Inward/Outward Projections/Protuberances.- Other “Don’t Touch” Skull Lesions: Arachnoid Granulations, Calvarial Depressions, Hemangiomas, and Intraosseous Lipomas.- Part III: Craniocervical Vasculature.- Craniocervical Vasculature: Introduction.- Aortic Arch and Great Vessel Origin Arterial Variants.- Cervical Carotid and Vertebral Arterial Variants.- Tortuous Cervical and Intracranial Arteries and Basilar-Carotid Dolichoectasia.- Miscellaneous Cervical Venous Variants.- Intracranial Posterior Circulation Variants.- Intracranial Anterior Circulation Variants.- Infundibular Outpouchings of Intracranial Arteries.- Persistent Carotid-Basilar and Carotid-Vertebral Anastomoses.- Variations in the Intracranial Venous System.- Arachnoid Granulations Within the Dural Sinuses.- Artifacts of the Craniocervical Venous System on MRI.- Artifacts of the Craniocervical Arterial System on MRI.- Artifacts on Craniocervical CT Angiography.- Dense Vessels Simulating Thrombosis on Nonenhanced CT.