Optomechanical measurement and FE modeling of tympanic membrane mechanics
-
Upload
jef-aernouts -
Category
Technology
-
view
227 -
download
1
description
Transcript of Optomechanical measurement and FE modeling of tympanic membrane mechanics
![Page 1: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/1.jpg)
Optomechanical measurement and FE modeling of tympanic membrane mechanics
Jef AernoutsLaboratory of Biomedical Physics (BIMEF)University of Antwerp
Presentation at Philips Group InnovationOctober 5, 2012
![Page 2: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/2.jpg)
2
Optomechanical measurement and FE modeling of tympanic membrane mechanics
![Page 3: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/3.jpg)
3
The human ear
tympanic
membrane
![Page 4: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/4.jpg)
4
Function of the ear
Convert sound (20-20000 Hz) > nerve activity in our brain
What is role middle ear?
![Page 5: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/5.jpg)
5
Why study TM mechanics?
• Middle ear finite element modeling
normal
diseasedreconstructed
tympanic membrane!
(Aerts J, Aernouts J. 2012)
(Gan et al., 2009)
(Kelly et al., 2003)
![Page 6: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/6.jpg)
6
Outline
1. Tympanic membrane elasticity
2. Tympanic membrane vibrations
3. Middle ear modeling
![Page 7: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/7.jpg)
7
Outline
1. Tympanic membrane elasticity
2. Tympanic membrane vibrations
3. Middle ear modeling
![Page 8: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/8.jpg)
8
Human tympanic membrane
- Base diameter: 9 mm- Apex height: 1.7 mm
![Page 9: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/9.jpg)
9
Needle indentation
• Approach- Apply indentations- Measure forces
(1) TM, (2): force transducer,
(3): piston, (4): LVDT , (5): signal
generator, (6): feedback control unit
![Page 10: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/10.jpg)
10
Needle indentation
• Approach- Apply indentations- Measure forces
• Sample preparation
![Page 11: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/11.jpg)
11
Needle indentation
• Approach- Apply indentations- Measure forces
• Sample preparation
• Shape measurement
![Page 12: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/12.jpg)
12
Needle indentation
• Approach- Apply indentations- Measure forces
• Sample preparation
• Shape measurement
• Finite element model
In rest
Indented
![Page 13: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/13.jpg)
13
Needle indentation
• Approach- Apply indentations- Measure forces
• Sample preparation
• Shape measurement
• Finite element model- Fit experiments
![Page 14: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/14.jpg)
14
![Page 15: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/15.jpg)
15
Outline
1. Tympanic membrane elasticity
2. Tympanic membrane vibrations
3. Middle ear modeling
![Page 16: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/16.jpg)
16
TM vibrations
• Sample
![Page 17: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/17.jpg)
17
TM vibrations
• Sample
• Stroboscopic holography- Sounds: 0.5 kHz –
19 kHz, 80-120 dB- Full-field displacement
![Page 18: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/18.jpg)
18
• Principle
Holography
CCD
![Page 19: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/19.jpg)
19
• Principle
• Stroboscopic holography
Holography
![Page 20: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/20.jpg)
sample
holography setup
speaker
probe microphone
camera
![Page 21: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/21.jpg)
21
FE model
• Geometry (from micro-CT)• Boundary conditions & Loadings
sound wave
![Page 22: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/22.jpg)
22
TM full-field displacement
- Measured with stroboscopic holography:
![Page 23: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/23.jpg)
23
TM full-field displacement
- Measured with stroboscopic holography:- Finite element outcome
![Page 24: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/24.jpg)
24
Outline
1. Tympanic membrane elasticity
2. Tympanic membrane vibrations
3. Middle ear modeling
![Page 25: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/25.jpg)
25
Middle ear FE model results
1000 Hz
(x8e3)
7000 Hz
(x3e4)
16000 Hz
(x2e5)
![Page 26: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/26.jpg)
26
Thanks for your attention!
• Questions? I’m all ears…
![Page 27: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/27.jpg)
27
TM curvature
• Cochlear load at umbo (tip malleus)• Natural curved versus artificially flat
![Page 28: Optomechanical measurement and FE modeling of tympanic membrane mechanics](https://reader035.fdocuments.us/reader035/viewer/2022070318/557a04abd8b42a1c0a8b4b34/html5/thumbnails/28.jpg)
28
TM curvature
• Umbo velocity response800 Hz – 4 kHz:
17.5 dB difference