Explore topic-wise InterviewSolutions in .

Right answer is (a) Hewlett Packard

The best explanation: The ST/AR (ST and Arrhythmia) algorithm from Hewlett Packard (1999) is a multi LEAD ECG algorithm DESIGNED for both arrhythmias and ST SEGMENT monitoring.

Right OPTION is (a) True

For explanation: Modern EMG machines are PC based available both in the console as well as laptop models as they provide full colour WAVEFORM display, AUTOMATIC cursors for MARKING and making measurements and a keyboard for access to CONVENIENT and important test controls. The system usually incorporates facilities for recording of the EMG and evoked potentials.

Right answer is (d) EEG

Explanation: ELECTROENCEPHALOGRAPH is an INSTRUMENT for recording the electrical ACTIVITY of the brain, by suitably placing surface electrodes on the scalp. EEG, describing the general function of the brain activity, is the superimposed wave of NEURON potentials operating in a non-synchronized manner in the physical sense.

Correct option is (a) True

Best explanation: Yes, PCG amplifiers usually have GAIN compensation circuits to increase the AMPLIFICATION of high frequency signals, which are usually of low intensity. The frequencies at the HIGHER end of the range are of PARTICULAR significance in research applications.

The correct option is (c) 4 sec

For explanation I WOULD say: A separate detector continuously EXAMINES the ECG signal for ventricular fibrillation. If a flutter or SINUSOIDAL wave-form persists for more than 4 seconds in an ECG channel, then the monitor ALARMS for ventricular fibrillation.

Right option is (c) 1.0 mm

Easy explanation: A new ACOUSTIC sensor, which enhances the audibility of HEART sounds and enables recording of quantitative acoustic SPECTRAL data is described by Kassal et al, 1994. This device is a polymer based adherent differential-output sensor, which is only 1.0 mm THICK.

The correct option is (d) EMG

Explanation: The INSTRUMENT is useful for making a study of several aspects of neuromuscular function, neuromuscular condition, the EXTENT of nerve LESION, reflex RESPONSES, etc.

Right OPTION is (a) Apexcardiograph

To EXPLAIN I would SAY: The apexcardiograph has limited applications. It is, however, useful in the DIAGNOSIS of the enlargement of the heart chambers and some type of valvular DISORDERS.

The correct answer is (c) forehead

Easy explanation: A pattern of electrodes on the head and the channels they are CONNECTED to is CALLED a montage. Montages are always SYMMETRICAL. The reference electrode is generally placed on a nonactive SITE such as the forehead or earlobe.

Right ANSWER is (C) EEG

Easy explanation: Electroencephalograph is an instrument for recording the electrical activity of the brain, by suitably placing surface electrodes on the scalp. EEG, describing the GENERAL function of the brain activity, is the superimposed wave of neuron potentials operating in a non-synchronized manner in the physical SENSE.

Right OPTION is (b) 200 ms, 120 ms

For explanation: After a QRS complex is identified, a search is MADE on each LEAD independently in the area prior to the R wave to DETERMINE if there is an associated P wave. This area is 200 ms wide and ends 120 ms before the R wave peak.

Right option is (a) LEAD Selector switch

For explanation I would say: The potentials picked up by the patient ELECTRODES are TAKEN to the lead selector switch. In the lead selector, the electrodes are selected two by two ACCORDING to the lead PROGRAM.

Right option is (c) ECG

To explain I would say: A‘STAND by’ mode of operation is generally provided on the electrocardiograph. In this mode, the stylus moves in RESPONSE to input SIGNALS, but the paper is stationary. This mode allows the operator to adjust the gain and BASELINE position CONTROLS without wasting paper.

Correct answer is (c) 192 ms

Best explanation: The QRS detector checks the QRS detection signal for the presence of the PEAK of an R wave. Search BEGINS after an ABSOLUTE REFRACTORY period from the previously identified QRS complex. The value used for the refractory period is 192 ms. This helps to prevent a T wave from being identified as an R wave.

Right option is (d) ECG

The best I can EXPLAIN: CMRR of the order of 100–120 dB with 5 kW unbalance in the leads is a DESIRABLE feature of ECG MACHINES. In addition to this, under specially adverse circumstances, it becomes necessary to INCLUDE a notch filter TUNED to 50 Hz to reject hum due to power mains.

The correct option is (d) EMG

Easy explanation: A TRAINED EMG interpreter can DIAGNOSE various muscular DISORDERS by LISTENING to the sounds PRODUCED when the muscle potentials are fed to the loudspeaker.

Correct answer is (c) Phonocardiograph

To ELABORATE: The phonocardiographs provide a recording of the waveforms of the HEART sounds. These waveforms are diagnostically more important and revealing than the sounds themselves.

The correct option is (a) MONOPOLAR

Explanation: EEG may be recorded by picking up the voltage DIFFERENCE between an active electrode on the scalp with RESPECT to a reference electrode on the EAR LOBE or any other part of the body. This type of recording is called ‘monopolar’ recording.

The correct answer is (B) Inoperative, ARTIFACT

Explanation: Beat Labeling means that the algorithm assigns the complex ONE of the FOLLOWING labels: NORMAL N, supraventricular premature S, ventricular ectopic V, paced P, questionable ?, and learning L. If the signal quality is not good, the algorithm assigns the label “inoperative I” and “artifact A”.

Right option is (C) Template

Explanation: A POPULAR approach in the DETECTION of arrhythmias is BASED on template matching. A model of the normal QRS complex, called a template, is derived from the ECG complex of a patient under normal circumstances.

Correct answer is (a) True

To elaborate: True. Bones serve as a reservoir for calcium and phosphorus, essential MINERALS for various CELLULAR activities that OCCURS throughout the body. The composition of bone depends on a LARGE number of factors: the species, which bone, the location from which the sample is taken, and the age, SEX, and type of bone tissue, for example, woven, cancellous, cortical.

Right answer is (d) PROSTHETIC device

The best explanation: An appliance that SUBSTITUTES for the loss of a particular function, generally by involving a DIFFERENT MODALITY as an input and/or output channel. An ARTIFICIAL limb, a sensory substitution system, or an augmentative communication aid is prosthetic devices.

The correct choice is (b) Pathophysiology

Easy explanation: Interruption or interference with normal physiological and developmental PROCESSES or structures is calledPathophysiology. Modality-Specific is a task that is specific to a single sense or movement pattern. FUNCTIONAL limitation is a restriction or lack of ability to PERFORM an action in the manner or within the range consistent with the PURPOSE of an organ or organ system.

The CORRECT answer is (c) 20 to 2000 Hz

The BEST I can explain: The amplifier used for a phonocardiograph has WIDE bandwidth with a frequency range of about 20 to 2000 Hz. Filters permit selection of suitable frequency BANDS, so that particular heart sound frequencies can be recorded.

The correct option is (a) Stethoscope

The EXPLANATION is: Heart SOUNDS are diagnostically useful. Sounds PRODUCED by HEALTHY hearts are remarkably identical and ABNORMAL sounds always corelate to specific physical abnormalities. From the beginning till today, the principal instrument used for the clinical detection of heart sounds is the acoustical stethoscope.

Correct answer is (B) False

The explanation: It is false. Bones are living tissues. They keep growing. They ALSO are responsible for the production of blood CELLS and act a mineral reservoir in the body. They also play the role of protection of internal soft organs like the brain is protected by the skull and lungs and heart by the RIB cage.

The CORRECT answer is (c) Time Measurements and HEART Rate Measurements

Explanation: Electrocardiograms are almost INVARIABLY recorded on graph paper with horizontal and vertical lines at 1 mm intervals with a thicker line at 5 mm intervals. Time measurements and heart rate measurements are made horizontally on the electrocardiogram.

Correct CHOICE is (C) SURFACE Electrodes

Easiest explanation: Electro-oculography is the recording of the bio-potentials generated by the movement of the eyeball. The EOG potentials are picked up by small surface electrodes placed on the skin near the eye.

The correct option is (a) True

Best EXPLANATION: The MODULE runs once EVERY second, depending UPON the quality of the signal. If the signal is ‘chaotic’ (a signal of poor quality that cannot be processed) or ‘noisy’ (a signal of intermediate quality), no PROCESSING is carried out.

The CORRECT answer is (d) 0.00015 V

For explanation I would say: In order to detect the QRS, the DETECTION threshold is kept as 0.15 mV to prevent the detection of T waves or baseline NOISE as QRS complexes during a COMPLETE heart block or asystole. For OPTIMAL performance and to prevent false alarms, the lead selected for monitoring should have adequate amplitude.

The correct ANSWER is (a) Cathode Ray Oscilloscope

Explanation: The Cathode Ray oscilloscope displays EMG waveforms. Electromyograph is an instrument used for recording the electrical activity of the muscles to determine whether the MUSCLE is CONTRACTING or not; or for displaying on the CRO.

Correct answer is (b) Noise sensitivity

The explanation: Friesen compared noise sensitivity of nine types of QRS detection ALGORITHMS. He established that an ALGORITHM using a DIGITAL filter had the BEST performance for the composite noise CORRUPTED data.

The correct option is (b) EMG

The explanation is: ELECTROMYOGRAPH is an instrument used for recording the electrical activity of the muscles to determine whether the muscle is contracting or not; or for displaying on the CRO and loudspeaker the action potentials spontaneously present in a muscle or those induced by voluntary contractions as a means of DETECTING the nature and location of MOTOR unit lesions; or for recording the electrical activity evoked in a muscle by the stimulation of its NERVE.

The correct choice is (C) Preamplifiers

Easy EXPLANATION: Good ELECTRODE impedance should be generally below 5 kilohms. Impedance between a pair of electrodes must also be BALANCED or the difference between them should be less than 2 kilohms. EEG preamplifiers are generally DESIGNED to have a very high value of input impedance to take care of high electrode impedance.

Right answer is (C) 6 mm

The best I can explain: Johnson et al (1977) designed a miniature amplifier circuit fully encapsulated in EPOXY resin with two SMALL silver electrodes of 6 mm diameter, exposed FLUSH with the base of the MODULE. The electrode is attached to the skin using adhesive tape.

The correct ANSWER is (d) VCG

To elaborate: In contrast, the electrocardiogram which displays the electrical POTENTIAL in any one single axis, the vectorcardiogram displays the same electrical events simultaneously in two perpendicular axes. This gives a VECTORIAL representation of the distribution of electrical potentials generated by the HEART and produces loop type patterns on the CRT screen.

Correct choice is (b) Time domain

For explanation: In the time domain CATEGORY, the compression technique is applied DIRECTLY to the samples of the ECG signal in the time domain to REMOVE redundant information. Examples INCLUDE the scan-along polygonal approximation and the amplitude ZONE time epoch coding.

Right choice is (d) Every 200 ms

The best I can explain: The contribution from each ECG lead to the QRS detection signal is PROPORTIONAL to its measured quality BASED on the waveform amplitude, and the amount of muscle and baseline noise. The weighting factors are UPDATED every 200 ms to ALLOW for a quick ADAPTION to signal quality changes.

Correct choice is (c) 20 MM/s

The explanation: Electrocardiograms are almost invariably RECORDED on graph paper with HORIZONTAL and vertical lines at 1 mm intervals with a thicker LINE at 5 mm intervals. Time measurements and HEART rate measurements are made horizontally on the electrocardiogram.