Medical Electronics

Question Bank

Unit I

ELECTRO-PHYSIOLOGY AND NON BIO POTENTIAL RECORDING

Part –A

1. Define Bio-electric Potential.The chemical activity of the cells, nerves and muscles of the body, variety of bio electric potentials are generated in our human body.

2. How a bio-electric potential is generated in a cell.Each cell is a minute voltage generator, positive and negative ions are tend to concentrated un equally inside and outside of the cell wall, a potential difference is established.

3. Mention the types of fluids in cell.a. ICF – Intra Cellular Fluidb. ECF – Extra Cellular Fluid

4. Mention the types of ions transporta. Primary Active Transport – Transport of the substances through the cell

membrane will occur by diffusion.b. Secondary Active Transport – Transport that is obtained by concentration

gradient. 5. What is Resting potential

Membrane potential caused by different concentration of ions is called as Resting Potential

6. What is Action PotentialThe positive potential of the cell membrane during excitation is called as the Action potential

7. Mention some Bio-electric Signalsa. Electrocardiogram (ECG)b. Electroenceplagrom (EEG)c. Cerebral Potentiald. Electromyogram (EMG)e. Electrogastrogram (EGG)f. Electroretinogram (ERG)g. Electrooculogram (EOG)

8. Define Bio-Potential Electrodes.Bio-potential electrodes are employed to pick up the electrical signals of the body

9. Half Cell Potential or Electrode Potential.The voltage developed at an electrode –electrolyte interface is designated as the “Half-Cell Potential” or “Electrode Potential”

10. Why electrode paste is used in employing electrodes?The dry outer skin of the body is highly non-conductive and will not established a good electrical contact with an electrode and skin, the skin is coated with an electrical conductive paste called “Electrode Paste”.

11.Mention the types of Electrodes.1. Microelectrodes

a. Metal microelectrode.b. Micropipet.

2. Depth & Needle Electrode3. Surface Electrode

a. Metal Plate Electrodesb. Suction cup Electrodec. Adhesive tape Electroded. Multipoint Electrodee. Floating Electrode

4. Chemical Electrodesa. Hydrogen or reference electrodesb. Practical reference electrodesc. pH electroded. PCO2 electrode

12. What are the distortions in measuring Bio-Potentiala. Type of material used in electrodesb. Movement of after fixing in the bodyc. Noise signal due to activity of nearby cells

13.Why we need biological amplifiersBio signals are having low amplitude and low frequency so, amplifiers are needed to boost the amplitude level of the bio signals.

14.What are the basic requirements of biological amplifiers High impedance (2MΩ to 10MΩ) It must have isolation and protection circuit used to protect the patients

from micro and macro electric shock Voltage gain should be greater than 100dB Constant gain should be maintained throughout the bandwidth Output impedance should be small Drift free amplifiers should be there CMRR(Common Mode Rejection Ratio) should be grater than 80dB Gain must be correctly calibrated

15. Mention the types of Bio-logical amplifiersa. Differential amplifiersb. Operational amplifiersc. Instrumentation Amplifiersd. Chopper amplifiers

i. Mechanical choppersii. Non-mechanical choppers

e. Isolation amplifiers16.What is electrocardiography

Electrocardiography (ECG) is electrical activity of the heart muscles. (or) An instrument recording ECG called Electrocardiography.

17.Mention the types of ECG lead systemsa. Bipolar lead systems (Standard)b. Unipolar lead systems (Augmented unipolar limb lead systems)

18. Write short notes on Einthovan Triangle.

Einthoven's triangle provides a way to understand the amplitude of the ECG waves. One way to verify that your data is correct is to plot the cardiac vector into the Einthoven triangle. For this: 1) construct an equilateral triangle with the base on top. Top will be lead I, right = lead III and left = lead II 2) from the middle point of each side, plot on the corresponding lead (triangle side) a segment of magnitude proportional to the amplitude of the QRS complex. 3) trace a line perpendicular to the segment at each end of the segment.

The perpendicular lines corresponding to the initial point of the vectors will intersect in the center of the triangle; the perpendiculars traced from the end of the vector should also intersect at one point. The line between the two intersections shows the orientation of the heart. This can explain differences in magnitude between your data and the nominal values.

19. Draw the ECG (lead I,II,III) waveforms

20.What is Electro encephalography?Study of electrical activity of brain is called Electro encephalography.

21.What are the types of brain`s action potential.a. Inhibitory Post Synaptic Potential (IPSP)b. Excitatory Post Synaptic Potential (IPSP)

22. Define Evoked potentialThis is developed in the brain as the responses to external stimulus like light, sound etc.,

23.Mention the types of Measurement methods in EEG signala. Anterior – Posterior (Front – Back Measurement)b. Lateral Measurements

24.Mention the EEG recording modes

a. Unipolar (potential of each electrode can be measured with respect to one reference electrode)

b. Augmented or Wilson Mode (Potential can be measured between one electrode and the average of all other electrodes)

c. Bipolar Mode (Potential can be measured between successive which are closely spaced).

25. Mention the applications of EEGa. Epilepsyb. Anesthtic levelc. Brain injuryd. Monitor during surgerye. Effect of yoga

26. What is Electromyogram?It is an instrument used for recording the electrical activity of the muscles to determine whether the muscle is contracting or not.

27.Define Electro Nerography.Recording of peripheral nerve`s action potential is called “Electronerography”

28.Mention the types of EMG electrodesa. Surface electrodesb. Needle electrodes

29. Mention the applications of EMGa. Electrophysiological testingb. Clinical neurophysiologyc. Neurologyd. Psychiatry

30. What is Electrooculogram?EOG is the recording of the bio potential generated by the movement of eyes.

31.Mention some applications of EOGa. The effect of some drugs on the eye movement systems can be identified

by using EOG.b. It is used to analyze the state of semicircular canals.c. Diagnosis of the neurologic disordersd. The level of anaesthesia can be indicated by the characteristic of eye

movement32.What is Phono Cardiogram?

The graphical record of heart sound is known as Phono Cardiogram. 33.What is Auscultation?

The technique of listening sound produced by organs and vessels of the body is known as Auscultation

34.What is Murmers?In abnormal heart, additional sounds are heared between the normal heart sound. These additional sounds are known as murmurs.

35.Mention the Classification of heart sound.a. Valve closure soundb. Ventricular filling soundc. Valve opening soundd. Extra cardiac sounde.

36.Mention the types of microphones used in PCGa. Air-coupled microphoneb. Contact microphone

37.What is mean by systole and systole

Systole: The contraction of the heart muscle, pressure 120mm of HgDiastole: The relaxation of the heart muscle, pressure 80mm of Hg

Part –B

1. Explain the factors that influence the design and application of a medical instruction system / Discuss the different characteristics of a medical instrument system. (8)

2. Explain the man-instrument system with a neat block diagram /Explain with a block diagram the components of the bio-medical instrument system. (8)

3. Discuss the problems encountered in measuring a living system /Discuss the major differences encountered between measurements in a physiological system as distinct from a physical system. (8)

4. Draw the structure of a living cell of our body and explain its constituents. (8) 5. Discuss the different ways of transport of ions through the cell membrane (4) 6. Give an account on the different chemical compositions in the intra and extra

cellular fluids and their effects in the case of blood serum. (4) 7. Discuss the development of action potential and muscular contraction. (8) 8. Draw the electrical equivalent circuit of microelectrode and explain its electrical

nature. (8) 9. What are bio-potential electrodes. Distinguish between metallic microelectrode

and nonmetallic microelectrode. (4) 10. Draw the micropipette nonmetallic electrode and explain (8) 11. With a neat block diagram, explain the working of ECG recorder (8) 12. Discuss the different lead configuration used in ECG. (8) 13. Explain with a neat diagram the resting potential (8) 14. Explain polarization, depolarization the depolarization (8)15. Draw the circuit diagram of an ECG isolation amplifier and explain its action. (8)16. What are chopper amplifiers and explain. (8) 17. Explain with a diagram medical preamplifier and explain its action (8) 18. Explain a bridge voltage amplifier and explain (8) 19. Explain buffer amplifier and explain (8)20. Explain a current amplifier circuit and explain its working. (8)21. Draw the curves of ECG and diagnose any form of disturbance in heart rhythm (8)22. Draw the block diagram of an EEG unit and explain the different parts in it. (8)23. Give the origin of brain waves and describe the 10-20 electrode system used in

EEG. (8)24. Describe the recording setup used in EMG (8)25. Write a note on ERG and EOG (8)26. Explain the origin of different heart sounds (8)27. Explain with diagram the salient features of Phonocardiography (PCG) (8)28. Draw the frequency response of

a. An electromyogram. (2)b. Blood flow measurements. (2)c. Phonocardiogram. (2) d. Plethysmogram (2)

29. (a) Write down the ‘Nernst Equation’ and ‘Goldman Equation’ and explain about the constants used. (8)(b) Explain

i. Bio Electric Potentials from the brain (4)ii. ii. Resting Rhythms of the Brain (4)

UNIT – II

BIO-CHEMOCAL AND NON ELECTRICAL PARAMETER MEASUREMENT

PART – A

1. Mention some bio-chemical measurements in human bodyElectrolytes measurement (Na, K, Cl)Blood Cell count measurement (White Blood Cell, Red Blood Cell and platelets)Blood gas measurements (PH, PO2, PCo2, PHCo2)

2. Mention some bio-chemical measurements in human body1. Electrophoresis2. Colorimeter3. Photometer4. Auto analyzer5. Cardiac output6. Respiratory Measurement7. Blood pressure measurement8. Blood cell counter

3. Define ElectrophoresisElectrophoresis is defined as the measurement of a solid phase with respect to a liquid (liquid – Buffer solution)

4. Mention the applications of Electrophoresis1. Measurement the quantity of protein in plasma, urine, etc.,2. Separate enzymes into their components isoenzymes3. Identification of antibodies

5. What are the factors affecting the speed of migrationa. Magnitude of chargeb. Ionic strength of bufferc. Temperatured. Timee. Type of support media

6. What is the use of calorimeterCalorimeter is used to measure the protein and iron levels in blood.

7. What is Beer`s LawA = aCL

whereA= Absorption of protein or iron contenta= AbsorbtivityC= Concentration of the absorbing substance in cuvetteL= Light path length of the cuvette

8. What are the parameters can analyze through the blood gas analyser? pH measurement of blood and other body fluids pO2 measurement pCO2 measurement pHCO3 measurement

9. Define calorimeter /photo metric principleThe basic principle used in calorimeter is absorbance and transmittance of biological substances mixed with chemicals.

10. Explain about Auto analyserAuto analysers are used to measure the blood chemistry and display readings with the graphical recordings.

11.What are the points to be consider in auto analyser Sterilization is needed for samples and glass tubes. Calibration of auto analyzers is very important

12.What is blood flow measurement.It is a method of measuring the rate of flow of blood in a vessel.

13.Mention the types of blood flow meters.a. Magnetic blood flow meterb. Ultrasonic blood flow meter

i. Transit time type ii. Doppler type

c. Thermal convention methodd. Radio graphic method e. Indication dilution method

i. Open circulation method ii. Closed circulation method

14. Define Cardiac outputCardiac output is the amount of blood delivered by the heart to aorta per minute, for normal adult cardiac output is 4-6 litters per minutes.

15. Mention the method involved in the cardiac output measurement 1. Fick’s method2. Indicator dilution method3. Impedance change method

16. Write the cardiac output equation for indication dilution method

WhereQ- Cardiac outputM- Mass of the bloodC- Concentration of Indicator

17. Write the cardiac output for impedance change method

WhereV- Volume of the thoraxρ- Resistivity of the patient`s haematocrit.A- Cross sectional area of the thoraxR- Resistance of thorax

18. Define respiratory measurement It is to measure acquiring oxygen in inhalation and eliminating CO2 in exhalation in the respiratory system.

19. What is gas LawThe set of rules to measure the respiratory functions in terms pressure, volume and temperature of air in human body is known as gas law.

20. Boyle`s LawIt states that the volume of gas varies inversely with the pressure of gas at constant temperature.

WhereV2 – Final Volume V1 – Initial VolumeP2 – Final PressureP1 - Original pressure

21. Define Charles`s LawIt states that the volume of gas is directly proportional to the absolute temperature at constant pressure

WhereV2 – Final Volume V1 – Initial VolumeT2 – Final TemperatureT1 - Original Temperature

22. Define Minute volume in respiratoryThe volume of air breathed by lung for one minute

23. Define Apnoea Apnoea is the stoppage of breathing, it leads to arrest of the circulation, it may cause due to drug overdose, head injury, etc.

24. What are the methods of blood gas analysis?Paramagnetic O2 Analyser, Thermal conductivity CO2 Gas Analyser

25. Define pulse rate / Heart ratePulse rate is the rate at which the blood pumped in to the body for circulation for a minute, heart rate is the rate of heart beats per minute.

PART – B

1. What is meant by vector cardiograph and how it is accomplished? (4)2. Explain the following electrodes with neat diagram

i. Hydrogen (8)ii. pH (8)

3. 7. Explain the following electrodes with neat diagrami. Pco2 (8)ii. Po2 (8)

4. What are biomedical electrodes? Explain the electrode PHCO3 with neat diagram. (8)

5. Draw the block diagram of an automatic blood cell counter and explain its functioning. (8)

6. Describe the principle of laser based blood cell counting using a schematic diagram(8)

7. Explain the following photometers with suitable diagrams.a. Filter photometer (8)b. Flame photometer (8)

8. Explain the working principle of spectrophotometer. (8)9. Explain the principle of chromatography and its applications in medicine. (8)10. Discuss the principle and working of electromagnetic blood flow meters. (8)

11. Describe an ultrasonic blood flow meter used in the measurement of velocity of blood flowing in the blood vessels. (8)

12. Describe ultrasonic Doppler blood flow meters. (16)13. Explain with a block diagram the laser based blood flow meter. (8)14. Explain the Fick’s method for the determination of cardiac output. (8)15. Explain the Indicator dilution method of cardiac output measurement. (8)16. Explain the thermo dilution method of cardiac output measurement. (8)17. Describe a method for the measurement of total lung capacity./ Describe the

plethysmograph method of measuring the total lung capacity. (8)18. Describe a spirometer with a suitable schematic diagram. (8)19. Explain in detail any one of the methods used for measuring blood pressure (8)20. Explain in detail any one of the methods used for measuring temperature (8)21. What is pneumotachograph? Give its importance in the pulmonary function

analysis.(8)22. Write down the application of Electrophoresis and explain the basic principle

involved(8)

UNIT III

ASSIST DEVICES AND BIO-TELEMETRY

PART - A

1. What is pacemaker?A device which is capable of generating artificial pacing impulses and delivering them to heart is known as pacemaker.

2. What are the components of pacemaker & what are its types?Pacemaker components are Pulse generator, electrodes and battery.Pacemaker types are, Internal pacemaker & External pacemaker.

3. What are the types of pacing modes & how the pulses are generated in competitive pacemaker?The pacing modes are classified as competitive and non- competitive mode. The competitive pacemakers are used to generate fixed rate pulses. It occurs along with the natural pulses generated by the heart.

4. What are the classifications of pacemaker based on the mode of operation?

Ventricular asynchronous pacemaker(fixed type pacemaker) Ventricular synchronous pacemaker. Ventricular inhibited pacemaker. Atrial synchronous pacemaker. Atrial sequential ventricular inhibited pacemaker.

5. What are the disadvantages of ventricular asynchronous pacemaker?1. By using this type of pacemaker, the heart beat rate cannot be

changed.2. It may lead to the occurrence of ventricular fibrillation.

6. What are the advantages and disadvantages of standby pacemaker? Advantages:

Ventricular fibrillation is avoided by using this pacemaker. Power consumption is reduced.

Disadvantages: This pacemaker is sensitive to electromagnetic interferences. There is no synchronization between atrial and ventricular contraction.

7. what is demand pacemaker?The pacemaker which provide the impulses based on the patient’s need is known demand pacemaker.

8. Give the specifications of Pacemaker.1. Weight : 33-98 grams2. Reliability (life time) : 3.5 -18 years3. End of life indicator : 2-10% drop in pulse rate.4. Pulse rate : 25-155 pulses / minute5. Pulse width : 0.1 – 2.3 milliseconds6. Pulse amplitude : 2.5 to 10 volts7. Battery capacity : 0.44 – 3.2 Amp- hours

9. What are different types of stimulation Pacemakers?1. External Stimulation.2. Internal stimulation.

10.Explain the difference between Internal & External Pacemaker.

11. What is

fibrillation? What are the types of fibrillation?The condition at which the necessary synchronizing action of the heart is lost is known as fibrillation. Types of fibrillation are:

Atrial fibrillation Ventricular fibrillation

12.What are the various electrodes used for defibrillation? Internal (spoon shaped) electrodes External (paddle shaped) electrodes

13. What is counter shock?The phenomenon of application of an electrical shock to resynchronize the heart is known as counter shock.

14. What is the need for Ventilator?It is used to provide artificial respiration. This should be applied to the patient, whenever respiration is suspended due to reasons like gas poisoning, electric shock etc.

15. What is IPP & define stimulator?IPP means Intermittent Positive Pressure. The positive pressure ventilators are used to inflate the lungs with IPP.Stimulator is the device used to stimulate

External Pacemaker Internal Pacemaker

The pacemaker is placed outside the body. It may be in the form of wrist watch or in the pocket.

The pacemaker is a surgically implanted when if the skin near the ches t or abdomen, with its output’s leads are connected directly to the heart muscle.

It does not require open chest surgery.

It requires open chest minor surgery to place the pacemaker.

There is no safety for the pacemaker. There is 100% safety for circuit from the external disturbances.

The external pacemakers are used for the temporary heart regularity.

Implanted pacemaker are used for permanent heart regularity.

innervated muscles and denervated muscles. It is used for the treatment of paralysis.

16.What is bio-telemetrya. Bio-telemetry is the measurement of biological parameters over long

distance b. For conveying biological information from a living organism and its

environment to a different location where this can be recordedc. This involves radio frequency signal as a carrier for modulation, referred to

as radio-telemetry17.What are the considerations should have design of bio-telemetry?

1. The telemetry system should be selected to transmit the bio-electric signal with maximum fiidelity and simplicity.

2. The system not effect the living system by any interference.3. Smaller in size and light in weight4. It should have more stability and reliability5. The power consumption at the transmitter and the receiver should be small.6. The system should reject common mode interference rejection7. The miniatured radio telemetry system should be used to reduce noise

18.What are the types of radio telemetry system?a. Single channel telemetry systemb. Multi channel telemetry system

19.Mention the various methods of transmission of bioelectric variablesa. Active measurementsb. Passive measurements

20.Mention the examples of single and multi channel telemetrySingle channel telemetry

a. Tunnel diode FM transmitter(for TX of ECG,EEG,EMG, Respiration rate)b. Hartley type FM transmitterc. Pulsed hartley oscillator (Tx of temperature signals)\d. Radio telemetry with sub carries system

Multi channel telemetrya. Frequency division multiplex telemetry systemb. Time division multiplex telemetry system

21.Mention the advantages of Bio-telemetry a. Used to record the bio signals over long periods and while the patient is

engaged in his normal activitiesb. Medical attendant or computer can easily diagonise the nature of disease

by seeing the telemetered biosignals without attending patient room.c. Patient is not disturbed during recordingd. Biotelemetry is extendend for monitoring patients in a hospital from a

remote location22.What is a radio pill?

A device used for bio-telemetry for monitoring the physiological activity of a human being, such as pH value of the stomach acid

PART – B

1. Describe the cardiac pacemaker waveforms and explain their importance. Compare external and implanted pacemakers. (8)

2. Explain with a diagram the ventricular asynchronous pacemaker (fixed rate pacemaker). (8)

3. Explain the ventricular synchronous pacemaker. (8)4. Explain working principle of demand pacemaker with a diagram. (8)5. Explain the atrial synchronous pacemaker. (8)6. Explain with a neat diagram, the working principle of D.C. defibrillator. (8)7. Explain with a neat diagram, the working principle of synchronized D.C.

defibrillator. (8)8. Explain the square pulse defibrillator. (8)9. Explain the block diagram of a bio-telemetry system. Discuss its design. (8)10. Explain the single channel telemetry system. (8)11. Draw and explain the telemetry circuit for the transmission of EMG, ECG, EEG

and respiration rate(16)12. Explain the subcarrier biotelemetry system. (8)13. Explain the multiple channel telemetry systems with neat diagrams. (16)14. What are the problems associated with the implant telemetry circuits? Explain

the uses of biotelemetry. (8)15. Explain the various modulation techniques used for transmitting a biosignal in

a telemetry system (8)16. Write short notes on telestimulation (8)17. What are the precautions to be followed in hospitals while using defibrillators

(4)18. Write briefly about the power sources used for implantable type of pacemaker

(8)19. What is radio pill? Explain. (8)20. Write technical properties of electrodes used in Defibrillator (4)21. Write short notes on ‘Frequency Selection’ with respect to Biotelemetry (8)22. Explain the basic concepts (including the modulation types) of radio

transmission used in biotelemetry (16)

UNIT IVRADIOLOGICAL EQUIPMENTS

PART - A1. What is the use of radio Isotopes?

Radio-Isotopes are used in medicine both for therapeutic as well as diagnostic applications

2. What is Ionizing Radiation?It a radiation comes from natural or manmade radioactive materials

3. What is non-ionizing Radiation?It is a radiation of radio waves, light, infrared radiation etc.,

4. How radio isotopes are used in medical diagnosis?A small amount of radioactive chemicals, (Tracers) are injected into an arm vein or administered through ingestion or inhalation, the tracers are travels into different parts of body, using radiation detectors images are received, processed through the images we can diagnose.

5. What is x-rays?X-rays are electromagnetic radiation located at the low wavelength end of the electromagnetic spectrum. The x-rays are used in the medical diagnostics.

6. Draw the Block diagram of x-Ray machine?

7. What are the different techniques to detect the X-Rays1. Fluoroscopy 2. X-ray films3. Image intensifiers

8. What is radiation therapy?The use of radiation for treatment of diseases has become an important sub-field of medicine call radiation therapy.

9. How ionizing radiation is generated?X-rays are generated when fast-moving electrons are suddenly decelerated by impinging on a target.

10.What are the physical effects detected in radioactivity.1. The activation it causes in photographic emulsions 2. The ionization of gases 3. The light flashes the radiation causes when striking certain minerals

11.Mention the basic types of radiation1. Alpha rays2. Beta rays3. Gamma rays

12.Write planck`s equation E= hfWhereE – EnergyH - Planck`s constant = 6.624X10-27

f - Frequency13.What is radioactive decay

The process by which radium or certain other materials emit radiation is called radioactive decay

14.What is radioactivityThe property of an element to emit radiation is called radioactivity

15.Draw the Instrumentation diagram for diagnostic X-rays

16. What is angiographyThe outline of blood vessels are made visible on the X-ray image is called angiography

PART – B1. Discuss in detail the radiation therapy techniques. (8) 2. Explain with suitable diagram the diagnostic X –Ray machine. What are the

applications of X-Ray examination? (16)3. Explain with suitable diagrams the working principle of the two types of

scintillation detectors for gamma radiation. (8)4. With a block diagram, explain the instrumentation system for radioisotope

procedures (8)5. Write short notes on the following detectors for beta radiation:

a. Gas flow counter (4)b. Liquid scintillation counter (4)

6. Draw the schematic diagram of a G.M. counter and explain its working details (8)

7. Explain the following radiation detectors.a. Expansion type cloud chamber (4) b. Diffusion type cloud chamber (4)c. Bubble chamber (4)d. Scintillation counters (4)

8. Describe the principle of visualizing body organs by radioisotope methods. (8)9. List out the properties of X-Rays (4)10. Write short notes on angiography (4)11. Explain the working principle of image intensifier with a neat block diagram (8)12. Write short notes on ionization chamber (8)13. Discuss about intensity duration curve. What is its use? (8)

UNIT VRECENT TRENDS IN MEDICAL INSTRUMENTATION

PART - A 1. What is thermography

A thermograph is a device that records temperatures over a fixed period of time. It consists of a rotating drum or disk and a stylus or pen. Often, a bimetal mechanism for measuring temperature change is used. The pen is affixed to the free end of the bimetal strip. As the drum or disk rotates, the pen makes a chart of the changes in temperature.

2. Define Infrared radiationInfra red ray is kind of electromagnetic wave higher frequency (more than radio frequency) and lies before the visisble light frequencyinfra red electromagnetic spectrum is usually 0.77µm and 100µm.

3. Define endoscopyAn endoscopy refers to a dedicated area where medical procedures are performed with endoscopic cameras, which are used to visualize structures and organs within in the body.

4. What are the types of endoscophic sytems available?

1. Rigid endoscope

2. Flexible endoscope / fiber endoscope5. What are the parts in regid endoscope?

1. Rigid endoscope with light cable2. Objective / lens - for image formation3. Rod lense system - for image transport4. Ocular lense - for image magnification

6. Define passive thermographyThe features of interest are naturally at a higher or lower temperature than the background. Passive thermograph has many applications such as surveillance of people on a scene and medical diagnosis specifically thermology.

7. Define active thermography An energy source is required to produce a thermal contrast between the feature of interest and the background. The active approach is necessary in many cases given that the inspected parts are usually in equilibrium with the surroundings.

8. What are the advantages of the thermograph? It shows a visual picture so temperatures over a large area can be

compared It is capable of catching moving targets in real time It is able to find deteriorating, i.e., higher temperature components prior to

their failure It can be used to measure or observe in areas inaccessible or hazardous

for other methods It is a non-destructive test method It can be used to find defects in shafts, pipes, and other metal or plastic

parts9. What are the types of laser beams used in medicine?

Pulsed Nd-YaG laser

Continuous wave CO2 laser Continuous wave Organ ion laser

10. Name the types of lasers used in medicine. Pulsed Nd-YaG laser. Continuous wave CO2 laser. Continuous wave organ ion laser.

11.What are the advantages of laser surgery? Highly sterile. Highly localized and precise. Non contact and bloodless surgery Short period of surgical time and painless surgery.

12. What are the applications of laser in medicine? Laser is used in opthalmography(eye problem) Gynecology (fertility), plastic surgery, skin cancer. Gastroentrology Orthopedics

13.Define laser in medicineLaser beam consits of high intense radiation in unique direction by focus the enrgy at one point, the enrguy band move form higher enrgy level to lower energy level, the laser beam is emitted to particular direction. It is used for many aplications in terms of diagnostic and theapheutic in medicine.

14.Define two types of emission in laser beam Spontaneous emission Stimulated emission

15.what are the applications of thermograph in medicine? Tumors Inflammation Brain Diseases Burns Orthopedic Diseases

16.What are the devices are used to protect against electrical hazards? Ground fault interrupt Isolation transformer

17.Define macro shockA physiological response to a current applied to the surface of the body that produces effect in body such as muscle contraction / tissue injury is called macro shock. The equipment user and the patients may get this macro shock due the malfunction of the system.

18.Define micro shockA physiological response to a current applied to the surface of the heart that produces effect in body such as muscle contraction / tissue injury is called macro shock. The micro shock occurs when current exceeds from 10micro amps.

19.What is leakage current?The extentaneous current flowing along a path other the intended, due to resistive , inductive or capacitive coupling with its main, the leakage current may occurs due to ungrounded equipment , broken wire and un equal ground potential

20.What is diathermy? List its types.Diathermy is the treatment process by which cutting, coagulation of tissues are obtained.Its various types are:

Shortwave diathermy

Microwave diathermy Ultrasonic diathermy Surgical diathermy

21.What are the advantages of diathermy? The treatment can be controlled easily. Use of appropriate electrodes permit the heat to be localized only in the

region to be treated. Amount of heat that is to be delivered can be adjusted accurately. Inter lying tissues, muscles, bones, internal organs etc., can be provided

with heat by using high frequency energy.22.Define shor wave diathemy

Short wave diathermy used to get relief of chronic pain in the body, it involves the high frequency 27.12 MHz and wavelength of 11 m, this high frequency currents are used to suppress the stimulation of sensory nerves and muscle contractions.

23.List out the advantages of electro surgical diathermy

i. It provides simple and effective surgeryii. It provides bacterial and infection free surgeryiii. Bleeding can be arrested by the coagulation method .

PART – B1. Explain with block diagram the infrared thermograph technique and its

merits and demerits. (8) 2. What are the medical applications of thermography (8)3. Mention the details of laser instrumentation for biomedical applications. (8)4. Discuss the laser principle and mention the different laser interactions on

our body. (8)5. Write short notes on HE-NE laser and the general applications of laser in

medicine (8)6. What are the uses of endoscopes in medicine? Describe any one of the

therapeutic instrument using an endoscope. (8)7. What are the different types of commonly available endoscopes and their

diagnostic applications? (4)8. Explain the liquid crystal thermograph in brief. (4)9. What are the techniques involved in electro surgery techniques using

diathermy units? (8)10. Draw the block diagram of short wave diathermy unit and explain. (8)11. Draw the block diagram of ultrasonic diathermy. (8)12. Explain in brief the salient features of microwave diathermy. (4)13. Discuss the range and area of irritation of different heating techniques in

diathermy. (4)14. Give an account on biological effects of radiation exposure and safe dose

equivalent limits. (8)15. Describe the construction and working of any one of the personnel

radiation monitoring equipment (8)16. Write a note on area monitoring in the case of radiation safety. (8)17. Explain the physiological effects of current at commercial frequencies on

human body (8)18. Describe the possibilities of occurrence of micro shock hazards in a

hospital(16)19. Explain the following with respect to ‘electrical safety’:

a. Ground fault interrupter (3)b. Isolation transformer (3)c. Line isolation monitors (3)d. Grounding (3)e. Important aspects of hospital architecture. (4)

20. Bring out the salient points of instrumentation ina. Endoscopy unit (8)b. Bio Medical Laser (8)