Dandy-Walker Malformation
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 –…
Aorta and Inferior Vena Cava
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…
Atrioventricular Septal Defect
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…
Intussusception
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:…
Brain and Spine
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…
Congenital Pulmonary Airway Malformation (CPAM)
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…
Perigestational Hemorrhage
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…
Iliac Arteries and Veins
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…
Carotid Arteries
TERMINOLOGY Abbreviations • Common (CCA), internal (ICA), and external (ECA) carotid arteries; vertebral artery (VA) GROSS ANATOMY Overview • CCA terminates by dividing into ECA and ICA • ECA is…
Reactive Adenopathy
KEY FACTS Imaging • US is ideal imaging modality for initial assessment of enlarged lymph nodes • Unilateral or bilateral • Reactive adenopathy: Absence of intranodal necrosis ○ Hypoechoic cortex…
