CHPT 4: Diagnostic Tests and procedures

electrodiagnostic procedures

Diagnostic procedures used to evaluate the function of the nervous system by recording electrical signals in the brain, spinal cord, and peripheral nerves.

electroencephalogram (EEG)

Record of the minute electrical impulses of the brain measured as alpha, beta, delta, and theta waves; used to identify neurologic conditions affecting brain function and consciousness.

evoked potentials

Record of minute electrical potentials (waves) extracted from ongoing EEG activity, used to diagnose auditory, visual, and sensory pathway disorders; also monitors neurologic function during surgery.

polysomnography (PSG)

Recording of various aspects of sleep, including eye/muscle movements, respiration, and EEG patterns, to diagnose sleep disorders.

lumbar puncture (LP)

Introduction of a specialized needle into the lumbar spine for diagnostic or therapeutic purposes, such as obtaining CSF for testing; also called spinal tap.

magnetic resonance imaging (MRI)

Nonionizing imaging technique using magnetic fields and radiofrequency waves to visualize anatomic structures, especially soft tissue like the brain and spinal cord.

magnetic resonance angiography (MRA)

Magnetic resonance imaging of blood vessels to detect pathologic conditions like thrombosis and atherosclerosis.

intracranial MRA

Magnetic resonance image of the head to visualize the vessels of the cerebral arterial circle, common sites for aneurysm or occlusion.

extracranial MRA

Magnetic resonance image of the neck to visualize the carotid artery circulation.

nuclear medicine imaging

Radionuclide organ imaging.

single-photon emission computed tomography (SPECT) brain scan

Scan combining nuclear medicine and computed tomography to produce images of the brain after radioactive isotope administration.

positron-emission tomography (PET)

Technique combining nuclear medicine and computed tomography to produce images of brain anatomy and physiology; used to study conditions like stroke and Alzheimer's.

radiography

X-ray imaging.

cerebral angiogram

X-ray of blood vessels in the brain after intracarotid injection of contrast medium.

computed tomography (CT) of the head

Computed tomographic images of the head used to visualize abnormalities like brain tumors.

myelogram

X-ray of the spinal cord obtained after intraspinal injection of contrast medium.

reflex testing

Test performed to observe the body's response to a stimulus.

deep tendon reflexes (DTR)

Involuntary muscle contraction after tendon percussion; positive findings indicate no response, diminished, normal, brisk, or hyperactive response.

Babinski sign

Pathologic response to plantar stimulation; positive when toes dorsiflex (curl upward); also called Babinski reflex.

transcranial Doppler sonogram

Image made by sending ultrasound beams through the skull to assess blood flow in intracranial vessels; used in stroke and head trauma cases.