thapliyal co2 lasers

8/6/2019 Thapliyal CO2 Lasers

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CO2 Lasers in Biomedicine

Tanuj Thapliyal

5/11/2010


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Link to presentation

This is a transcribed version of the

presentation

The actual presentation can be found here:

http://prezi.com/njrss5m1oxjm/


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History & Basic Facts

One of earliest and most powerful lasers every made

Invented by C. Kumar Patel in 1964 @ Bell Labs

One of the first lasers ever invented, after Ruby laser and HeNe laser

Extremely efficient laser optical power out/electrical power in from 5 to 20%

Comparison: HeNe or Ar/Kr lasers have .1 % efficiency

IR laser diodes have higher efficiency, >50%

Highest power continuous wave laser

Operates at 9.4 and 10.6 micrometer wavelengths


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Theory of Operation

Traditional Laser Operation has direct electron

excitation

Laser consist of:

Active Medium (gas, crystal, semiconductor,

liquid)

Pump (Optical, Electrical)

Laser Cavity between 2 mirrors (100% reflective,

partially reflective mirrors)


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Theory of Operation

1) Excited active medium --> electrons at excitedenergy levels (POPULATION INVERSION)

2) When electrons relax back to ground state,

they release energy in form of a photon at aspecific wavelength and in phase (coherent)

3) Photons bounce back and forth in cavity bymirrors, allowing more stimulated emission of

excited electrons and amplification of laser light 4) Photons that pass through partially reflective

mirror is the "LASER" light


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Theory of Operation


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Theory of Operation

CO2 Lasers use molecularvibrations for laser action

Typical CO2 Laser ActiveMedium

10-20% Nitrogen 10-20% CO2

60-80% Helium

Trace % of Hydrogen and/orXenon

Methods of Excitation Radiofrequency

Pulse Width Modulation

DC


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Theory of Operation

1) Plasma, or heat vibrates Nitrogen in gas mixture

2) Nitrogen vibrations remain for long time because they'resymmetric

3) Nitrogen vibrational frequency couples nicely with

energy required to bring CO2 electrons up to 3rd energylevel

4) When CO2 electrons relax from 3rd to 2nd energy levels,photons are released

5) Helium accomplishes 2 functions a) Helps CO2 relax to ground state b) Improve thermal conductivity of active medium

Hot CO2 --> electrons stay in 2nd energy level, negating populationinversion


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General Advantages

The CO2 Laser's power makes it like a great but collaterally dangerous scalpel

10.6 micrometer wavelength energies nicely absorbed by water and organic tissue--> for soft tissue ablation

Narrow, focused area of energy delivery

Cauterizes wounds and seals off nerves and small blood vessels - a good but notgreat coagulator

Laser acts like a natural sterilizer as it functions, reducing secondary infectionoccurences

Less swelling (generally no crushing of tissue)

Precision


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Histology and Scalpel


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General Disadvantages

Slow recovery

can be painful post-operation

Surrounding tissue damage can be massive andmust be carefully controlled by not applying laser

for too long

Expensive procedures

ll fl ibl id


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Small, flexible waveguides

revolutionized CO2 lasers in minimally

invasive surgery CO2 lasers in minimallyinvasive surgery had limitedapplication due to large,bulky, and unwieldy energydelivery systems

Advent of flexible hollowwave guides in mid 2000'shas allowed for increasedapplications of CO2 lasersin surgery since hard toreach tissue can now beeasily accessed


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Otology

Two major types of ear surgeries

CLASS (CO2 laser Assisted StapesSurgery) CO2 laser is used in middle/inner ear

surgery where innermost bone of the ear(stapes) is removed and replaced withprosthesis to improve hearing by better

conducting sound to inner ear Surgery needed when stapes no longer

functioning properly, a result ofotosclerosis (spongy bone hardensaround base of stapes)

CLEAR (CO2 laser Enabled Ablationand Resection) Diseased tissue removal during other ear

surgery procedures Adhesion ablation

Scar tissue dissection

Debulking and coagulation of vasculartumors

Flexible CO2 laseradvantageous here because:

1) Flexible sheath means surgeoncan hold laser in hand allowing

extremely high precision indelicate, small space

2) There is increased visualizationin tight area so surgeon can bettersee the operation

3) Hemostasis of tinymicrovasculature occurs

http://www.youtube.com/watch?v=X_z3T1TPjjw
http://www.youtube.com/watch?v=X_z3T1TPjjwhttp://www.youtube.com/watch?v=X_z3T1TPjjw


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Dentistry

Hollow wave guide allows flexible control to hard to reach places in the mouth

Co2 lasers coagulate and seal the sensory nerve endings, reducing need foranasthesia and postoperative pain

Treats: benign oral lesions:

fibromas

papillomas Hemangiomas

gingival hyperpasias

aphthous ulcers

ankyloglossias

premalignant lesions: lichen planus

oral leuokoplakia

CO2 laser doesn't enhance ability to cure oral disease compared to scalpel,electrosurgery, or cryotherapy

Scalpel and electrosturgery still method of choice

Ad d di l di


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Advanced cardiovascular disease

produces intense discomfort in

afflicted patients After a heart attack, tissue is dead and unableto conduct action potentials and beat theheart; blocked arteries prevent blood flow to

heart tissue

leads to condition called angina, chest pain or

discomfort that occurs when heart muscleisn't getting enough oxygen via blood toperform its functions


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The Solution - Trans-Myocardial

Revascularization (TMR)

Heart tissue is deliberately punctured with a

laser to stimulate growth factors and induce

blood vessel formation to provide tissue with

oxygen

This process is also combined with manually

introduced growth factors and gene therapy

to further induce vascularization

http://www.youtube.com/watch?v=sxwWeQNUa04
http://www.youtube.com/watch?v=sxwWeQNUa04http://www.youtube.com/watch?v=sxwWeQNUa04


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Modes of Treatment

Controversy over efficacy of therapy as many claim it tobe a placebo effect, despite this, it's obtained FDA 510kpremarket approval in 2 laser treatment methods

Including CO2, 3 Laser treatments pursued

CO2 PLC Medical Systems, CO2 Heart Laser 2

Early pioneering work used CO2 using 80 watts of power Since it took long time to make holes in heart tissue at that low energy,

heart had to be non beating

New lasers pulse with heartbeat (on order of several millisecond

pulses) so it can work on a beating heart, but will only ablate whenthe heart is still (1000 watts)

Excimer (PhotoMedex, didnt work, approach abandoned)

Holmium:YAG (Cardiogenesis, market leader)


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Note on Prezi

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References 1 of 2

http://www.springerlink.com/content/l5544513105012q1/

http://www.metacafe.com/watch/2990146/co2_fractional_laser_skin_resurfacing_skin_rejuvenation_operation_demo/

http://www3.interscience.wiley.com/journal/119162392/abstract?CRETRY=1&SRETRY=0

http://en.wikipedia.org/wiki/Carbon_dioxide_laser

http://www.vetlaser.com/

Laser surgery: using the carbon dioxide laser.

V. C. Wright

Can Med Assoc J. 1982 May 1; 126(9): 10351039.

http://www.lasertreatments.com/Laserwrinkle/

Ibrahim Tuncer, Ceyda zakr-Tomruk, Kemal encift, Sedat lolu. Photomedicine and Laser Surgery. February 2010, 28(1): 75-79.

doi:10.1089/pho.2008.2353. http://www.israel21c.org/health/israeli-researchers-pioneer-laser-treatment-for-sealing-wounds

http://www.cnn.com/2008/HEALTH/12/19/laser.surgery/index.html

http://www.laserk.com/newsletters/whiteCO.html

Agarwal, Ravi, Ajit, Mullasari, Kurian, Valikapathalil M., Rajan, Sethuratnam, Arumugam, Sarasa B., Cherian, Kottoorathu M.Transmyocardial laser revascularization: early results and 1-year follow-upAnn Thorac Surg 1999 67: 432-436

http://phx.corporate-ir.net/phoenix.zhtml?c=116437&p=irol-homeprofile

http://www.umm.edu/heart/tmr.htm

Patel, C. K.N. (1964). "Continuous-Wave Laser Action on Vibrational-Rotational Transitions of CO2". Physical Review136 (5A): A1187A1193. doi:10.1103/PhysRev.136.A1187.

http://repairfaq.ece.drexel.edu/sam/laserco2.htm

http://www.infoplasticsurgery.com/facial/non-surgical/wrinkles/laser

OH Frazier, RJ March and KA Horvath, Transmyocardial revascularization with a carbon dioxide laser in patients with end-stage coronary arterydisease, N Engl J Med341 (1999), pp. 10211028

Keith A. Horvath, Chia Yang J. Lu, Emmanuel Robert, Glenn F. Pierce, Rodney Greene, Barbara A. Sosnowski, and John DoukasImprovement of myocardial contractility in a porcine model of chronic ischemia using a combined transmyocardial revascularization and genetherapy approachJ. Thorac. Cardiovasc. Surg., May 2005; 129: 1071 - 1077.

http://my.clevelandclinic.org/heart/disorders/cad/tmr.aspx
http://www.springerlink.com/content/l5544513105012q1/http://www.metacafe.com/watch/2990146/co2_fractional_laser_skin_resurfacing_skin_rejuvenation_operation_demo/http://www3.interscience.wiley.com/journal/119162392/abstract?CRETRY=1&SRETRY=0http://en.wikipedia.org/wiki/Carbon_dioxide_laserhttp://www.vetlaser.com/http://www.lasertreatments.com/Laserwrinkle/http://www.israel21c.org/health/israeli-researchers-pioneer-laser-treatment-for-sealing-woundshttp://www.cnn.com/2008/HEALTH/12/19/laser.surgery/index.htmlhttp://www.laserk.com/newsletters/whiteCO.htmlhttp://phx.corporate-ir.net/phoenix.zhtml?c=116437&p=irol-homeprofilehttp://www.umm.edu/heart/tmr.htmhttp://en.wikipedia.org/wiki/Digital_object_identifierhttp://dx.doi.org/10.1103%2FPhysRev.136.A1187http://en.wikipedia.org/wiki/Digital_object_identifierhttp://dx.doi.org/10.1103%2FPhysRev.136.A1187http://repairfaq.ece.drexel.edu/sam/laserco2.htmhttp://www.infoplasticsurgery.com/facial/non-surgical/wrinkles/laserhttp://my.clevelandclinic.org/heart/disorders/cad/tmr.aspxhttp://my.clevelandclinic.org/heart/disorders/cad/tmr.aspxhttp://www.infoplasticsurgery.com/facial/non-surgical/wrinkles/laserhttp://repairfaq.ece.drexel.edu/sam/laserco2.htmhttp://dx.doi.org/10.1103%2FPhysRev.136.A1187http://en.wikipedia.org/wiki/Digital_object_identifierhttp://www.umm.edu/heart/tmr.htmhttp://phx.corporate-ir.net/phoenix.zhtml?c=116437&p=irol-homeprofilehttp://www.laserk.com/newsletters/whiteCO.htmlhttp://www.cnn.com/2008/HEALTH/12/19/laser.surgery/index.htmlhttp://www.israel21c.org/health/israeli-researchers-pioneer-laser-treatment-for-sealing-woundshttp://www.lasertreatments.com/Laserwrinkle/http://www.vetlaser.com/http://en.wikipedia.org/wiki/Carbon_dioxide_laserhttp://www3.interscience.wiley.com/journal/119162392/abstract?CRETRY=1&SRETRY=0http://www.metacafe.com/watch/2990146/co2_fractional_laser_skin_resurfacing_skin_rejuvenation_operation_demo/http://www.springerlink.com/content/l5544513105012q1/


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References 2 of 2

SARAH C CLARKE and PETER M SCHOFIELDPercutaneous myocardial laser revascularisationHeart, Mar 2000; 83: 253 - 254.

Myocardial revascularization by laser: a clinical report.

M Mirhoseini, J C Fisher, and M Cayton

Lasers Surg Med. 1983; 3(3): 241245.

M Mirhoseini, S Shelgikar, and MM CaytonNew concepts in revascularization of the myocardiumAnn. Thorac. Surg., Jul 1988; 45: 415 - 420.

Aaberge, Lars, Nordstrand, Kenneth, Dragsund, Morten, Saatvedt, Kjell, Endresen, Knut, Golf, Svein, Geiran, Odd, Abdelnoor, Michel, Forfang,KolbjornTransmyocardial revascularization with CO2 laser in patients with refractory angina pectoris: Clinical results from The Norwegian RandomizedTrialJ Am Coll Cardiol 2000 35: 1170-1177

Horvath K Ai , Zhou Y i . Transmyocardial Laser Revascularization and Extravascular Angiogenetic Techniques to Increase Myocardial Blood Flow.Cohn Lh, ed. Cardiac Surgery in the Adult. New York: McGraw-Hill, 2008:733-752.

http://www.plcmed.com/Products-CO2-Technology.asp

http://www.cardiovascularbusiness.com/index.php?option=com_articles&view=article&id=15040

http://www.nhlbi.nih.gov/health/dci/Diseases/Angina/Angina_WhatIs.html

G. Chad Hughes, Alan P. Kypson, Brian H. Annex, Bangliang Yin, James D. St. Louis, Shankha S. Biswas, R. Edward Coleman, Timothy R. DeGrado,Carolyn L. Donovan, Kevin P. Landolfo, and James E. LoweInduction of angiogenesis after TMR: a comparison of holmium:YAG, CO2, and excimer lasersAnn. Thorac. Surg., Aug 2000; 70: 504 - 509.

http://www.encyclopedia.com/doc/1G1-69075103.html http://www.medicalnewstoday.com/articles/18466.php

http://www.lifescienceintelligence.com/market-reports-page.php?id=HRI-059

http://www.drdaveanddee.com/warts.html

http://www.realself.com/question/Best-laser-acne-scars-treatment-Laser-or-Dermabrasion

http://www.saturdayeveningpost.com/2010/04/27/wellness/medical-update/energy-medicine.html

http://www.medicalnewstoday.com/articles/187306.php

http://www.omni-guide.com/surgeons-otology-and-neurotology.htm
http://www.plcmed.com/Products-CO2-Technology.asphttp://www.cardiovascularbusiness.com/index.php?option=com_articles&view=article&id=15040http://www.nhlbi.nih.gov/health/dci/Diseases/Angina/Angina_WhatIs.htmlhttp://www.encyclopedia.com/doc/1G1-69075103.htmlhttp://www.medicalnewstoday.com/articles/18466.phphttp://www.lifescienceintelligence.com/market-reports-page.php?id=HRI-059http://www.drdaveanddee.com/warts.htmlhttp://www.realself.com/question/Best-laser-acne-scars-treatment-Laser-or-Dermabrasionhttp://www.saturdayeveningpost.com/2010/04/27/wellness/medical-update/energy-medicine.htmlhttp://www.medicalnewstoday.com/articles/187306.phphttp://www.omni-guide.com/surgeons-otology-and-neurotology.htmhttp://www.omni-guide.com/surgeons-otology-and-neurotology.htmhttp://www.medicalnewstoday.com/articles/187306.phphttp://www.saturdayeveningpost.com/2010/04/27/wellness/medical-update/energy-medicine.htmlhttp://www.realself.com/question/Best-laser-acne-scars-treatment-Laser-or-Dermabrasionhttp://www.drdaveanddee.com/warts.htmlhttp://www.lifescienceintelligence.com/market-reports-page.php?id=HRI-059http://www.medicalnewstoday.com/articles/18466.phphttp://www.encyclopedia.com/doc/1G1-69075103.htmlhttp://www.nhlbi.nih.gov/health/dci/Diseases/Angina/Angina_WhatIs.htmlhttp://www.cardiovascularbusiness.com/index.php?option=com_articles&view=article&id=15040http://www.plcmed.com/Products-CO2-Technology.asp

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