Vertebral Stenosis/Occlusion
KEY FACTS Imaging • Plaque formation: Proximal vertebral artery (VA) > distal VA • Grayscale imaging ○ Chronic occlusion: Contracted vessel caliber; VA may be hard to demonstrate • Spectral…
KEY FACTS Imaging • Plaque formation: Proximal vertebral artery (VA) > distal VA • Grayscale imaging ○ Chronic occlusion: Contracted vessel caliber; VA may be hard to demonstrate • Spectral…
KEY FACTS Terminology • Encephalomalacia : Brain ischemia or inflammation • Porencephaly : Focal destruction of brain tissue • Hydranencephaly : Complete destruction of cerebral hemispheres Imaging • Intracranial bleeding…
KEY FACTS Terminology • Classic Dandy-Walker malformation ○ Cerebellar vermis is completely or partially absent ○ Cystic dilatation of 4th ventricle (4V) ○ Enlarged posterior fossa with elevated tentorium –…
TERMINOLOGY Abbreviations • Inferior vena cava (IVC) Definitions • “Proximal” and “distal” in arterial and venous systems apply to position of arterial and venous segment in relation to heart (rather…
KEY FACTS Terminology • Central cardiac defect involving atrial (ASD) and ventricular (VSD) septal defects, atrioventricular (AV) valves, and conducting system ○ Balanced : Right and left ventricles are equal…
KEY FACTS Terminology • Invagination or telescoping of 1 segment of gastrointestinal tract and its mesentery (intussusceptum) into lumen of adjacent distal segment (intussuscipiens) Imaging • Bowel within bowel appearance:…
EMBRYOLOGY AND ANATOMY Key Embryological Concepts • Multiple processes occur during embryological development of brain and spine • Neurulation : Ectodermal cells form midline neural plate in which folds develop…
KEY FACTS Imaging • Variable appearance from solid-appearing (microcystic) to complex cystic mass (macrocystic) ○ Macrocystic : 1 or more cysts ≥ 5 mm – May have single large cyst…
KEY FACTS Terminology • Perigestational hemorrhage (PGH): Hematoma in subchorionic space adjacent to gestational sac (GS) • Subchorionic hematoma is synonymous with PGH Imaging • Hematoma appearance depends on age…
GROSS ANATOMY Arteries • Abdominal aorta ○ Testicular and ovarian arteries originate below renal arteries ○ Median (middle) sacral artery is small, unpaired branch from posterior aspect of distal aorta…