Neurophysiology, Audiology & Ophthalmic Imagery Flashcards
Neurophysiology
the investigation and diagnosis of disorders of the nervous system, these may not be suitable for patients with cardiac pacemakers
Electroencephalography (EEG)
Small round, sticky electrode are placed on the scalp to detect electrical activity in the brain. They can be used to diagnose epilepsy, dementia, brain tumours & sleep disorders. There is a very SMALL chance of causing a seizure
Nerve conduction studies
Used to test the speed of electrical impulses travelling along nerves, A recording electrode s placed on the skin (arm or leg) and another electrode is used to stimulate the skin. It can detect if the nerve is trapped, damaged or diseased then the signals will be altered.
Electromyography
A small needle is placed into a muscle to view and listen for electrical impulses within the muscle. The test provides information about the muscle and the nerve supplying the impulse
Evoked Potential
Electrodes are placed on the scalp as well as the nerve in the arm or leg. Visual and hearing pathways are stimulated, and nerves. Their responses is recorded by the electrodes
How are audio, visual and nerve’s stimulated?
For audio pathways, patients are asked to listen for clicks through headphones.
For visual pathways, patients are asked to watch a checkerboard tv screen.
For nerve impulses, an electrical pulse is applied in the wrist or ankle.
Ophthalmic tests
Measure the health of the eye, including pressure (tonometry) and visual field tests
Angiographic tests
Measure blood flow in the eye, by injecting into the arm and monitoring it’s progress through blood vessels and to the eye. A retinal camera is used.
Tonometry
A light is shone into the eye to check for tissue fluid pressure. It can be used to diagnose glaucoma & muscular disease
Visual field test
Measures peripheral vision of the eye (edge to edge). It can be used to measure brain tumours, stroke, or heart disease.
Otoscope
A tool which shines a beam of light into the eye to help visualise the ear canal & eardrum. It doesn’t however provide a quantitative measurement as results are visual
What does an otoscope help to diagnose?
inflammation
presence if wax
foreign bodies
A small puff of air may ne injected to observe the ear drums movement
Tympanometry
A small probe is placed into the ear, and air is slowly pushed into the ear to test how the eardrums move and the fluid in the inner ear. The results are called a typogram (a graph).
