MEDICAL
ELECTRONICS
PRESENTED BY
P.SUBATHRA DEVI,AP/ECE
WHAT?
A branch of electronics
Electronic instruments and equipment
are used
Design concepts to medicine and
biology for healthcare purposes
Application of Engineering principles
Seeks to close the gap between
Engineering and Medicine
WHY?
Electronic devices are increasingly
being seen in the field of medicine.
For the better service of patients not
only in hospitals but also outside the
hospitals.
For advance healthcare treatment,
including diagnosis, monitoring, and
therapy.
For eg:
Ultrasound representation of
Urinary bladder
Components - Medical Instrumentation
system
Display
Recorder
Signal
conditioner
Measurand
Sensor
Input
Output
Measurand (Physical quantities):
Position, displacement
Temperature,pressure
Sensor:
is a device that detects a change in a
physical stimulus and turns it into a signal
which can be measured or recorded
Signal conditioning:
Amplifying,waveshaping,filtering,
rectifying,…
Display & Recorder:
Oscilloscope,ECG,ERG,EMG,etc….
Common medical measurands
Bioelectric Signals
ECG -Electro-Cardiogram, Heart activity
EMG -Electro-Myogram, Muscle
movement
EOG -Electro-Oculogram, Eye movement
EEG -Electro-Encephalogram, Electrical
activity along the scalp
Right arm, Left arm, Right Leg, Left
Leg
Any three Electrodes will be active
Lead I
Lead II
Lead III
Einthoven Triangle
ECG Waveform
P Wave -the right atrium to the left
atrium - 80ms
PR interval - sinus node through the
AV node and entering the ventricles.-
120 to 200ms
QRS Complex- depolarization of the
right and left ventricles. -80 to 120ms
T Wave - repolarization (or recovery)
of the ventricles.-160 ms
Eye movements to the left and right
EOG - applications
● Diagnostics
● Functional analysis
● Human Computer Interfaces
EEG - Electroencephalogram
EEG Electrode – cap locations of
the 10/20 system
EEG range is classified as
Delta 0.5 to 4 Hz
Theta 4-8 Hz
Alpha 8-13 Hz
Beta 13-22 Hz
Gamma 22-30 Hz
EEG - applications
● Diagnostics (Epilepsy, Oncology, ..)
● Sleep Analysis
● Human Computer Interfaces
● Pharmacology
● Intensive Care, Monitoring
Other Bioelectrical signals
Apexcardiograph
Ballistocardiograph
Electroretinograph
Vectorcardiograph
Electrode & electrode paste
To pickup the electrical signals of the
body
Electrode paste is used to have a firm
contact between body & electrode.
Types:
Based on the surface where we have
to get the bioelectrical signal.
Needle electrode
To record the nerve’s action potentials.
Insulated metal wire is bent at one end
& is inserted through the lumen of the
needle.
Surface electrode
To sense EEG & EMG
Types: Metal plate, suction cup,
Adhesive tape
Surface electrodes
Vagina / rectal electrodes
Depth electrode
To study the electrical activities of
neuron
To inject medicines into brain.
To measure oxygen tension.
Multipoint & Floating electode
Contains nearly 1000 fine active
contact pins
The metal does not contact subject
directly.
Other Electrodes:
Singe disk gold
plated electrodes
Ear clip electrode
Other Electrodes:
PH Electrode
PCO2 Electrode
PO2 Electrode
Microelectrode
1.Metallic Micro electrode
2.Non-Metallic Microelectrode
Components
Amplifiers
Filters
Rectifiers
Transformers
Oscillators
ADC
DAC
Timing circuits
Buffer
Multiplexer
Defibrillators
For life-threatening cardiac
dysrhythmias, ventricular fibrillation
Electrical energy to the heart with a
device called a defibrillator
Allows normal sinus rhythm
Ventricular fibrillation results from:
Coronary occlusion
Electrical shock
Abnormalities of body chemistry
Defibrillator
DC Defibrillators-Circuit
Recent trends
Remote patient monitoring
Radio pills
E-health
VLSI tools
ASIC-application specific IC
FPGA
SOC
Expectations
portability and miniaturization,
connectivity, safety, data security and
quality, and reliability.
dynamic power path management
(DPPM)
increased efficiency
Tips for healthy life
Eat healthy.
Exercise.
Leave some time for leisure.
Make the decision not to worry.
Work to understand what stresses
you.
Leave time to laugh.