laser applns

8/8/2019 Laser Applns

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-Presented by

R.S. Jaiya Dharshini

S. Elakkia


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The highly collimated beam of a laser can be further focused to a microscopicdot of extremely high energy density.

This makes it useful as a cutting and cauterizing instrument.

Cauterizing is a long-standing medical practice of using a hot instrument or ahigh frequency electrical probe to singe the tissue around an incision, sealing offtiny blood vessels to stop bleeding.

The cauterizing action is particularly important for surgical procedures in

blood-rich tissue such as the liver.

Lasers are used for photocoagulation of the retina to halt retinal hemorrhagingand for the tacking of retinal tears.

Higher power lasers are used after cataract surgery if the supportive membrane

surrounding the implanted lens becomes milky. Photo disruption of themembrane often can cause it to draw back like a shade, almost instantlyrestoring vision.

A focused laser can act as an extremely sharp scalpel for delicate surgery,cauterizing as it cuts.


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Garment industry

Heat treatment

Medical

Laser printingWelding and cutting

CDs and optical discs

SurveyingCommunication

Laser cooling

Spectroscopy

Laser nuclear fusionBarcode scanners


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Laser therapy for tumors

Cosmetic surgery (including laser hairremoval and removing tattoos)

Eye surgery Angioplasty

Soft tissue surgery

Laser scalpel

Dentistry and oral surgery Vascular surgery

Neuron surgery

Photobiomodulation


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Process of removal of

blockage in arteries. Major techniques:

1.Balloon angioplasty

2.Laser angioplasty

Instead of balloon tippedcatheter, a laser tip isused, in laser therapy.


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LASER types used:

1.CO2 laser

2.Ar laser

3.Nd:YaG laser

High intensity laser light can cure cancer, byshrinking or destroying tumors.

Applied through a flexible endoscope fittedwith OPTICAL FIBERS.

Can be used for treating cervical, penile,vaginal, lung cancers and its symptoms.


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The Ho:YAG is the best nowadays

Allow for segmental resection of all stones,

regardless of their composition

Accurate fiber contact against a calculus is the

primary safety factor


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The CO2 laser emits in the infrared light, at 9.4to 10.6 m

It usually is coupled with a visible helium-neon

beam for guidance Its beam is highly absorbed by water, hence

suited for surgery.Therefore, it vaporizes water-dense tissues to a

superficial depth of less than 1 mm


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Used in various like opthalmology, oncology,dentistry, manufacturing, etc.

Emits infrared beam at 1064 nm

Has good hemostatic (coagulates blood vesselsas much as 5 mm in diameter) and suitable forlithotripsy


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Solid state laser operating in

visible light range (694 nm)

Mostly used in range findingCosmetic surgeries like

tattoo and hair removal


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Most commonly usedtype

Their wavelength can

be tunedWide usage in

telecommunication,range finding and laser

therapyUsed for tissue

coagulation andthermal treatment ofsolid organs


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LASIK(laser-assisted in situkeratomileusis) is forcorrecting myopia,

hyperopia, andastigmatism.

Steps:

1.Flap creation

2.Remodelling

3.Re-positioning of flap


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A worm made a nest for itselfin John Matthews eye.

It took two laser blasts forthe doctors to remove it inthe Iowa university andhospitals.


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Lasers offer less pain, minimal scarring, reducedpost-surgical complications and superiorcosmetic results when compared with othermethodologies. Condyloma acuminata Penile carcinoma in the early stages (eg, CIS, T1 or T2)

Cutaneous hemangiomas (highly indicated)

FO cables, miniature video cameras and

special instruments are inserted into thebody.


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Photograph of the laser delivery handpiece with ahollow fiber for sensing temperature. Thesurgeon is repairing a 1 cm-long arteriotomy.

Courtesy: http://lasers.llnl.gov/mtp/tissue.html

Laser Tissue Welding

Laser tissue welding uses laser energy to activate photo thermal bonds and/or

photochemical bonds. Lasers are used because they provide the ability to accuratelycontrol the volume of tissue that is exposed to the activating energy.


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PREVENTION OF DENTAL CARIES WITHLASERS

Laser can be used for prevention of dental caries.

Different types of lasers increases the resistance to dental

caries by reducing the rate of demineralization of substance oenamel & dentin.

Argon laser alters the surface characteristics of enamel tomake it caries resistant.

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MECHANISM OF ACTION

Carbonate is lost from carbonated appetite mineral of toothduring laser irradiation

Pulsed co2 laser irradiation interacts with thephosphate group in dental materials

It gets preferentially absorbed & transformedefficiently to heat

Carbonated hydroxyapetite in the surface & in theimmediate subsurface of enamel is heated at temp.greater than 400`c

Carbonate is decomposed, leaving behind the a

hydroxyapetite like mineral that is less soluble


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BLEACHING WITH LASERS

- Power bleaching is the term used for acceleratedin-office tooth whitening procedures, using laser orXenon plasma arc-curing light.

(A). ARGON LASER

- A true laser light is delivered to chemical agent.

- The action is to stimulate crystals in the chemical.

- No thermal effect, so less dehydration of enamel.

- The treatment time is 10sec. per application per tooth.It is the advantageous for clinician & patient.


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(1).Minimal damage to surrounding tissues.

(2).Haemostatic effect by sealing blood vessels.

(3).Reduction of postoperative inflammation &

edema.

(4).Little postoperative scarring.


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(5).Reduction in postoperative pain sensationsince nerve endings are blocked.

(6).Dressing & suturing is not required forwound closer.

(7).Operating time is reduced.

(8).Sterilization of wound due to reduction inin amount of microorg. exposed to laserirradiation.

(10).Excellent wound healing.

(11).Laser exposure to tooth enamel causesreduction in caries activity.


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DISADVANTAGESDISADVANTAGES OF LASERSOF LASERS

(1).Laser beam could injure the patient or operator

By direct beam or reflected light, causing retinal

burns.


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(2).It available only atbig hospital &

treatment is veryexpensive.

(3).Specially trainedperson is needed.


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