Revision Flashcards
What element in the body is targeted during an MRI scan?
Hydrogen
What is it about oxygen that makes it the one that is targeted?
There is so much of it in the Body
Why do nuclei with and uneven number of protons and neutrons interact with a magnetic field?
They act like mini magnets
How is a very large magnetic field created in an MRI?
Superconducting magnet
The magnetic nuclei align their nuclear skins in a direction parallel to the magnetic field. A piece of equipment is used to excite the Low energy nuclei to a higher state that the others. What is the piece of equipment called?
Radio frequency coils
What is the name given to the frequency at which nuclei can absorb energy?
Larmor frequency
What follows the period of excitement?
Relaxation time
What is the form of energy released during the period after excitement?
Radio waves
How is the origin of the signal found?
Gradient coils
State the necessary precautions that must’ve taken before entering an MRI room?
No metallic objects No pacemaker No coins No jewellery No credit cards No tattoos
Why might a patient be uncomfortable or experience discomfort when in an MRI scan?
Very loud
Claustrophobic
Takes long
What are the features on an MRI scan that make the technique useful in medical diagnostics?
Very clear images (more detail)
Non ionising
Two types of thermometers?
Digital thermometer (thermistor) Digital infrared sensor (tympanic thermometer)
How do you use a digital thermometer?
Used in mouth, armpit or rectum
How do you use a digital infrared sensor?
Detects infrared waves when placed in ear
What is the range of body temperatures that you body can survive?
26-44 degrees
What is normal body temperature?
37 degrees +/- 0.5 degrees
What is the medical term for a patient who has an above normal body temperature? What symptoms might they exhibit?
Hyperthermia- headache, nausea, sweating, dizziness, fainting, confusion and muscle cramp
What is the medical term for a patient who has a below normal body temperature? What symptoms might they exhibit?
Hypothermia- tired, dizzy, blue tinge, uncomfortable shivering, slurred speech, increased heart rate, blood pressure falls, less urine output
What could/ would cause an incorrect body temperature reading to be taken?
Eating/drinking before taking reading Electric blanket Drugs/ alcohol consumption Ear wax Not waiting long enough
What are the similarities in the method of obtaining an ECG and EEG?
Both involve measurements of electrical activity
What equipment is used during an ECG?
Electrodes
What equipment is used during an EEG?
Electrodes
If a patient has had an elliptical seizure, what type of scan should they have?
EEG
If a patient shows signs for bradycardia, what type of scan should they have?
ECG
If a relaxed patient is emitting alpha waves, what type of scan should they have?
EEG
If a sleeping patient is emitting delta waves, what type of waves should they have?
EEG
If a patient exhibits brain death, what type of scan should they have?
EEG
Describe the structure and function of the endoscope that is used to create clear images inside the body?
Incoherant bundle- illuminate body part Coherant bundle- the retrieve image Eyepiece/camera- to form/view image Objective lens- to focus rays into coherant bundle Air irrigation channel to clean
What part of the endoscope extracts samples from the body?
Operations channel or tools channel
