CT, CAT - x-ray computed tomography
imaging of brain, spine, organs, blood vessels, sinuses, bones, fractures, tumors, ct-guided biopsy
MRI - magnetic resonance imaging
high resolution images of the brain
spinal abnormalities (tumor, abscess), edema, hemorrhage, blodd flow, infarcgts, tumors, infection, internal organ structure, more soft tissue-oriented
produces a map of the position, size, form, and nature of soft tissue organs. Real-time images show motions as in the fetus or heart. blood vessels, blood flow
EMG - electromyography
used to differentiate nerve and muscle disease and to evaluate neuromuscular disorders: myasthenia gravis, muscular dystophy...
ECG - electrocardiogram
records the electical umpulsed that stimulat the heart to contract.
ECG - P wave
atrial contraction started by impulse from the SA node.
absent or altered = cardiac impulse originates outside SA node.
ECG - PR interval
time required for the impulse to travel from the SA node to the atrioventricular node.
shortened= shortcut to ventricle (WPW syndrome).
lengthened= 1st degree heart block, delay in the av node.
ECG - QRS complex
widened= abnormal ventricular depolarization time
ECG - ST segment
time btwn completion fo ventricular depolarization and beginning of repolarization.
Transient ischemia (angina), muscle injury (early-stage of myocardial infarction)
ECG - T wave
ECG - QT interval
duration of ventricular repolarization
varies with age, sex, heart rate and meds
ECG - U wave
repolarization of the purkinje fibers within ventricles
Spinal Tap - applications
1) diagnosis 4 diseases: meningitis, subarachnoid hemorrhage, CNS malignancy & multiple sclerosis/autoimmune disease
2) introduce anesthetics
3) ID pathogens in acute or chronic inflammation
4) ID extent of brain infarction/stroke
Spinal Tap - contraindications
infection at puncture site, bleeding diathesis, raised intracranial pressure, & Chiari I malformation obstuction CSF.