Pulsed dye laser in dermatology
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Transcript of Pulsed dye laser in dermatology
Pulsed Dye laserPulsed Dye laser In In DermatologyDermatology
ByByManal SalahManal Salah
Ass.Prof. of dermatologyAss.Prof. of dermatology
NILES Cairo UniversityNILES Cairo University
Vascular LasersVascular Lasers
Argon(488-514nm)Argon(488-514nm) KTP(532nm)KTP(532nm) Dye(585,590,595,600nm)Dye(585,590,595,600nm) Nd-YAG(1064nm)Nd-YAG(1064nm)
Indications Of Indications Of Vascular LasersVascular Lasers
Vascular NeviVascular Nevi Vascular malformationsVascular malformations
Pyogenic granulomaPyogenic granuloma Venous lakesVenous lakes AngiokeratomaAngiokeratoma TelangiectasiaTelangiectasia AngiofibromaAngiofibroma
RosaceaRosacea Keloids & Scars Keloids & Scars
(existing&prophylactic)(existing&prophylactic) WartsWarts Striae distensaeStriae distensae PostAcne scarsPostAcne scars PsoriasisPsoriasis XanthelasmaXanthelasma
Argon Laser
Gas Laser• Wavelength 488 - 514 nm
• Pulse duration CW - Pulsed • Spot size 1- 2 mm • Chromophore Haemoglobin & Melanin
KTP Laser
Solid state Laser
• Wavelength 532 nm •Pulse duration CW - Pulsed - Q switched •Spot size 1, 2, 4 mm •Chromophore Haemoglobin & Melanin
Nd:YAG Laser
Solid state Laser• Wavelength 1064 nm • Pulse duration CW - Pulsed - Q switched Long pulsed • Spot size variable • Chromophore Non specific
Dye Lasers
Lasers containing fluorescent dyes dissolved in a common solvent e.g. alcohol or water,that absorbs light at one wavelength and emits light at another wavelength.
Dye lasers work based on the theory of SelectivePhotoThermolysis(SPTL)which means :- Site specific-Thermally mediated injury of-Microscopic tissue targets-By selectively absorbed pulses of radiation.
Dye Lasers
*For Vascular Lesions
*Wavelength
*Pulse Duration
*Chromophore
585nm OR 585,590,595,600nm
450 & \ OR 1500 microseconds Up to 40 msec
Oxyhaemoglobin
Dye Lasers
Why 585 nm?Oxyhaemoglobin has 3 peaks for light
absorption: * 418nm (The strongest) * 542nm * 577nm (The deepest & least
absorbed by melanin)
585nm was found to be deeper than 577nm& less absorbed by melanin.
Absorption CurvesAbsorption Curves
Thermal Thermal Relaxation TimeRelaxation TimeThe time necessary for the The time necessary for the
target chromophore to cool target chromophore to cool down 50%, through the down 50%, through the transfer of its heat to transfer of its heat to surrounding tissue via surrounding tissue via thermal diffusion.thermal diffusion.
In order to get OPTIMUM results:* The wavelength must be well absorbed by
oxyhaemoglobin, less by melanin & of deep penetration.* The pulse duration must be shorter than or equal to the TRT of the target.
This makes the majority of the absorbed energy to be retained by the target structure & minimizes non-specific thermal damage.
Delivery System
Flexible fiberoptic with different size
changeable hand pieces (2, 3, 5, 7,10,
&2x7 or 3x5 mm ).
Pretreatment measures *A written consent *Anesthesia (usually topical)
*Safety measures(precautions)
Safety measures(precautions) Protect eyes ……….. eye glasses &
shields.
Laser off or standby when not in use.
Plume or steam ……….smoke evacuator. Avoid reflecting objects. * Labeling the theatre.
Treatment Technique
PWS - Energy TestPWS - Energy Test
Treatment Technique
* Determine the MPD.
* Determine the treatment test dose .
* Choose the test site
Treatment Technique
*Pulse delivery. *Evaluation and frequency of revisits.
*Patient should know that treatment may be prolonged from months to years.
spots with overlap of 10% are required to cover effectively
DIRECTION OF TREATMENT
lase
r
Post treatment measures
*Sun screen for at least 6 months after the end of last session. *Topical antibiotic ointment once/day until disappearance of purpura.
Complications Of Laser treatment
*Generally it is very safe with very low incidence of side effects, and can be used at any age. -Scarring(<1%). -Hyperpigmentation ( 10 - 15% , transient, resolves in 2-3 months). -Hypopigmentation (5%, transient,resolves within 2 months).
Pediatric Port Wine Pediatric Port Wine StainStain
Before Treatment
Following Treatment
Photo Courtesy ofMilton Waner, MD
Adult Port Wine StainAdult Port Wine Stain
Before Treatment Following Treatment
Photo Courtesy ofMilton Waner, MD
Facial TelangiectasiaFacial Telangiectasia
Before Treatment Following Treatment
Photo Courtesy ofChris Zachery, MD
Facial TelangiectasiaFacial Telangiectasia
Before Treatment Following Treatment
Photo Courtesy ofDavid McDaniel, MD
RosaceaRosaceaBefore TreatmentBefore Treatment
Following TreatmentFollowing Treatment
Photo Courtesy ofDavid McDaniel, MD
Leg VeinsLeg Veins
Pre TreatmentPre Treatment 33 weeks post treatmentweeks post treatment
Courtesy: Emil Tanghetti. MD