Tumors and Vascular diseases of the Brain

1. Tumors and Vascular diseases of the Brain April 3, 2008

2. Jennifer Villa Frabizzio, M.D. • Abington Memorial Hospital • Radiology Group of Abington, PC • Board Certified in Diagnostic Imaging with Added Qualifications in Neuroradiology

3. Topics for Discussion Neuroimaging Then and Now Neuroanatomy Vascular and Nonvascular Vascular Disorders Diagnosis and Treatment Tumors Primary and Metastatic Disease

4. Neuroimaging- Then Standard Radiograph Pneumoencephalography Direct Cerebral Angiography

6. Pneumoencephalograhy • Introduced in 1919 by American Surgeon Dandy Walker • Primary method of Neurodiagnosis used late until late 1970’s early 1980’s • Lumbar puncture performed in sitting position • Patient placed in somersault chair with head suspended in harness • CSF removed and 10-15 mls of air introduced • Patient is tilted upside down and 50-60 mls more air introduced

7. Pneumonecephalography cont. Air outlined brainstem structures and supra tentorial structures to diagnose masses, tumors and cerebral atrophy Very time consuming, could take from one to two hours to perform Following the procedure patients invariably developed severe headache and maybe a fever Sampling of CSF post procedure showed high protein and white blood cells, which seemed to be a response to the air Symptoms would usually resolve within 48hrs

15. Direct Cerebral Arteriography • Pioneered in 1927 by Dr. Egas Moniz • Needle was inserted directly into the common carotid artery in the neck and contrast material injected • Rapid series of radiographs were taken of the skull in numerous projections • Currently studies are preformed by inserting a catheter into the femoral artery • Remains as gold standard for imaging arterial and venous structures

18. Neuroimaging-Now • Computed Axial Tomography • CAT SCAN • Magnetic Resonance Imaging • MRI

19. Computed Tomography • From Greek tomos (slice) and graphein (to write) • Generation of three dimensional images for a series of two dimension Xrays taken around a single axis of rotation • Computer generated images produce an axial image • Early CT scans in early 1970’s had single slice, allowing imaging of the brain in four minutes • Modern state of the art scanners can have up to 200 slices and can image the whole body in 30 seconds • Iodine base contrast material in injected in an arm vein to optimize visualization of vessels and solid organs • Uses ionizing radiation to obtain images, and should be used with caution in pregnant or pediatric patients

22. CT cont. • Advanced techniques CT angiography and venography • Contrast rapidly injected into an arm vein and timed to visualize arteries and veins • Has become first line minimally invasive procedure to image the intracerebral vasculature and coronary arteries • CT perfusion • Rapid imaging of the brain after contrast injection followed by computer post processing can generated area in the brain at risk for stroke

25. Magnetic Resonance Imaging (MRI) Powerful magnetic field used to align hydrogen atoms in the body Radiowaves are activated that alter the alignment of this magnetization, allow for the atoms to relax at different rates according to their chemical composition These signals are manipulated to reconstruct images of the body Greater soft tissue contrast than CT No ionizing radiation Must be extremely careful to remove all metal from patients Contraindicated in patients with pacemakers

28. MRI cont. • Advanced techniques • MR Angiography detection of moving molecules done without the injection of contrast to visualize flowing blood excellent to visualize head and neck vessels • Gadolinium based contrast agent is injected into an arm vein, mixed with flowing blood and allows for visualization of vessels especially in the chest and abdomen

30. MRI cont. • Diffusion imaging • For visualization of acute stroke, damaged cells swell and cause restricted diffusion • MR spectroscopy • Separating the chemical composition of brain lesions into different peaks to determine chemical composition • Functional MRI • Using changes in blood flow to monitor neural activity

35. Neuroimaging Nonvascular

39. Neuroimaging Vascular

49. Vascular diseases Stroke Trauma/Intracranial Hemorrhage Aneurysm Arteriovenous Malformations

50. Stroke • Acute episode leading to a neurologic deficit • 80% are due to ischemia (either thrombotic or embolic) • 20% other • Transient ischemic attack (TIA) • Focal events that resolve in 24hrs