(Left) Sagittal T1WI MR in a leukemia patient with leg weakness following intrathecal chemotherapy shows normal appearance of the conus and cauda equina. (Right) Sagittal T1WI C+ MR in a…

 Iniencephaly  Syndromic occipital encephalocele Pathology • Severity classified by sac contents • Cephalocele contents: Meninges, cerebellum, brainstem ± cervical cord, occipital poles, vasculature  Disorganized (neuronal migration anomalies, cortical dysplasias) and gliotic brain…

(Left) Axial graphic shows the anteromedial approach (green line), which uses the space between the sternocleidomastoid muscle and the tracheoesophageal complex medially. The anterolateral approach (black line) posterior to the…

 Very rare in antibiotic era  General paresis, dementia, tabes dorsalis (sensory ataxia with bowel and bladder dysfunction) Clinical Issues • Lower extremity weakness, pyramidal signs, bowl and bladder dysfunction, polyradiculopathy • Nontreponemal…

Anteroposterior radiography depicts a typical supernumerary hemivertebra positioned between the right L2 and L3 vertebral levels, resulting in convex right scoliotic curvature. Coronal T1WI MR depicts a small left thoracic…

(Left) Sagittal graphic of a disc bulge shows generalized extension of the disc margin beyond the vertebral body . An axial view must show generalized extension > 90° of the…

(Left) Thoracolumbar anteroposterior radiograph demonstrates sclerotic focus within the lower thoracic vertebral body, adjacent to the pedicle. There is characteristic nonaggressive appearance with sclerotic density and brush-like margins that suggest…

 Crowded foramen magnum, arachnoid adhesions, 4th ventricular arachnoid veil  Cisterna magna impacted by tonsils (“tight cisterna magna”) Clinical Issues • Most common symptoms  Chiari-like headache  Neck or back pain  Scoliosis • Carefully…

 If not attached to occipital bone, process is isolated rod-like bony element called massa paracondylica  Portions may be pneumatized from mastoid air cells Top Differential Diagnoses • Assimilation of C1 into…

Rheumatoid Arthritis Measurements CV Junction Trauma Measurements (Left) Sagittal graphic of craniocervical junction shows Wackenheim clival line (red) extending tangent to the normal odontoid position. The line is drawn from…