1. Vanderbilt University Department of Biomedical Engineering
Device for Quantification of Re-Innervation of a Laryngeal Muscle
Advisor: Dr. David Zealear
Designers: Thomas Thomasson and Nirav Patel
February 25, 2000

2. Background
What ?- Development of a design and technique for the quantitative measurement of a re-innervated laryngeal muscle
Why ?- To increase quality of life for patients suffering from denervated muscular system
Who ? - Patients that have lost muscle control through paralysis of laryngeal muscles (estimates of 15,000/yr)

3. Background Cont...
How ?- Recording EMG readings passes through the developed circuitry while tactile stimulation of the nerves is performed
Analysis? -Integrated recordings over time show degree of re-innervation and muscle fiber reconstruction counts

4. Objectives To Measure electromyographical potentials using electrodes.
To establish an index of synkinesis that compares pathological nerve re-innervation to normal nerve alignment
To use index of synkinesis to determine severity of pathology.
To measure muscle fiber bundles that have been re-innervated (secondary measurement of paralysis severity)

5. Circuit Bandpass Filter Removes DC noise and high frequency AC noise
Cutoff frequency of 1 Hz and 1000 Hz
Rectifier
Returns absolute value of input
Integrator
Calculates area under input curve
Peak Detector
Holds maximum value from the integrator

6. High Pass Filter Cutoff frequency of 100 Hz
Removes DC Voltage entering Circuit

7. Low Pass Filter
Cutoff frequency of 100K Hz

8. Full Wave Precision Rectifier
Positive Wave Rectifier: Vout = Vin 
Diodes Act Linearly in Feedback Loop

9. Integrator
Integrates the Rectified Wave Over Time by the equation: Vout = -1/(Rf Cf )  Vin dt

10. Peak Detector
Holds the Maximum Positive Output from the Integrator

11. Current Work
Finish Debugging Integrator After Consulting Dr. Galloway and Dr. Massengill
A digital output meter will be bought to be added to the circuitry as a final output source
Development of index of synkinesis through statistical analysis upon completion of canine experiments
DesignSafe has been begun; consultation with Sebastien Daleyden and Vincent Goussen on Monday

12. Future Work Hard-wiring will begin after circuit passes initial test
Calculations for timing sequences of tactile stimulation will be discussed with Dr. Zealear
Testing of circuit with control canine experiments

13. References
Farmer, Stephen and Douglass Hay. The Airway Epithelium. Vol 55. Marcel Decker, New York: 1991.
Dworkin, James and Robert Meleca. Vocal Pathologies. Singular Publishing, San Diego: 1997.
Michaels, L. Pathology of the Larynx. Springer-Verlag, Great Britain: 1984.