Diagnostic imaging final

Diagnostic

Determine physical signs without changing biological systems

Therapeutic

Make changes that improve function of patient

When filtering physiological signals, which type of filter would be best to reject 60-Hz
(power-induced) noise?

Notch Filter

Reproducibility

The ability of an instrument to give the
same output for equal inputs

Resolution

Smallest incremental quantity that can be
measured with certainty

Zero Offset:

Output quantity measured when input is
Zero.

Accuracy

Error divided by the true value. Usually
given as %

Precision

Expresses the number of distinguishable
alternatives from a given result

Sensor

Senses change in physical quantity and

Transducer

Converts energy into different forms

Electrode

Gets electrical without changing forms

Actuator

Produces motion or force

What’s the difference between passive vs. active transducers?

Passive doesn’t need a power source

Direct transducer

Measures quantity

Indirect transducer

Measures a related quantity and calculates

Invasive transducer

Enters the body

Non invasive transducer

Works externally

What is a VERY COMMON signal conditioning circuit for Biomedical instrumentation
inputs

Wheatstone bridge

What is the typical range of resistance for human skin?

15k ohm - 1M ohm

Due to the nature of medical treatments, patients in hospitals are more susceptible to
electric shock hazards. Below, list the REASONS (given from the text) why this is true

Skin drops to 150 ohms when wet

MACROshock & MICROshock:

Current enters from surface and exits from surface

Describe Leakage Current

Current that isn’t working but not the result of a fault

Earth leakage Current:

Main parts of apparatus to earth

Enclosure Leakage Current:

Conductive parts to earth

Patient Leakage Current:

Current flows through patient

Define a Line Isolation Monitor

Monitor current in outlets

What are the three organizations (mentioned in the PowerPoint lecture) that provide
safety regulations/standards for medical equipment?

AAMI

NFPA 99

IEC60601

What does the acronym PACS stand for

Picture Archiving communication system

What are the three main types of Mobile x-Ray Units

Line powered

Capacitor discharge

Battery powered

Of the three mobile x-ray units discussed, which is the most effective and best solution to issues
caused by making the x-ray machine mobile

battery

What is the definition of mammography?

xray of boobs

Compared to traditional X-ray machines, how much power does a Mammography unit use

less

What is the Gantry?

House many system components

What other equipment is housed in the gantry?

Power supplys

What is the Compression Assembly

Squeeze the boobs

What is MQSA an acronym for?

Mammography Quality standards act

Regarding Digital mammography, what does “double reading” mean

Software that flags spots for radiologist

What is the definition for Tomography?

Image is a slice of the patient

Regarding general Tomography, what sets the thickness for the “slice”

Tube angle/ blurring

How does Tomography “focus” on one part of the anatomy?

Blurs the rest

What is the difference between conventional and computed Tomography (CT)

Conventional is limited

What are Radio isotopes?

Used to prevent diagnose and cure disease

Regarding Nuclear imaging techniques What is the purpose of these techniques?

Allows for description of organs function

How much radiation does the patient receive compared to conventional X –Rays

Regarding Nuclear imaging techniques:

less

What is a Gamma Camera?

Absorbs gamma ray emanating from patient

What does MRI stand for

Magnetic resonance imaging

How does an MRI machine work? (What is the process that interacts with a patient and then
creates a digital image?)

Uses nuclear magnetic resonance to image nuclei of atoms

What are the main drawbacks to the MRI system?

Create 120 db

Metal objects become dangerous projectile

What devices should NOT be used or “worn” during an MRI scan? (Hint: these are typically ON
or implanted in a patient)

Any electronic or magnetized foreign bodies