Power point presentation on excimer

1. EXCIMER LASER
IN
DERMATOLOGY
Dr. Shama Naaz (Junior Resident)

2. Introduction
2
WHAT IS EXCIMER• Excimer = excited dimer = a molecule that only exists
in the excited state

3. HOW DOES THE ENERGY OF THE
PHOTON DEFINE THE WAVELENGTH
Presentation title 3
• If all the photons have the same Energy (E, - E,), they will all have the same wavelength
• If all the photons have the same wavelength, the global spectrum is narrow - band

4. WHY 308nm IS THE BEST
WAVELENGTH
Presentation title 4
308 nm is the best
wavelength: High
Efficiency & low risk

5. DIFFERENCE BETWEEN EXCIMER and
EXCIPLEX
Presentation title 5
Excimer =excited dimer Exciplex = excited complex
An Excimer is a dimer X-X that only
only exists in an excited level of enerqy
Exciplex is a complex X-Y that only
exists in an excited level of energy
Examples:Xe-Xe is a dimer Examples:• Xe-CI is a complex

6. EXCIMER LAMP
Presentation title 6
• Clarteis developed the smallest electronic architecture in the world to perform
• .Pulses of more than 7000 Volts
• More than 200000 times per second
• Which complies with all medical electronic regulations in the world.

7. SPATIAL AND SPECTRAL
DISTRIBUTIONS
Presentation title 7
• Xe-CI emission spectrum is naturally narrow-band
• Power distribution of excimer lamp is very homogenous in the output window(All treated zones receive the same
treatment (unlike with excimer lasers)

8. EXCIMER @308nm : LAMP V/S LASER
- PHYSICS
• Same gas (Xenon +
Chlorine)
• Same pulsed
electrical generator
• Same chemical
reaction
• Same photons
generated
• Same wavelength
Presentation title 8
Excimer lamp Excimer laser
Spontaneous emission
All directions
Non coherent light
Stimulated emission
Collimated beam
Coherent light

9. EXCIMER
@308nm :
LAMP V/S
LASER -
BIOLOGY /
MEDICINE
Similar results

10. EXCIMER @308nm : LAMP V/S LASER -
COMMERCIAL PRODUCTS
Presentation title 10
Excimer lamp Excimer laser
1 Kg
Up to 100 mW/cm?
Large spot size
~ 15 lakh INR
No additional costs
70 kg
Up to 150 mW/cm?
Small spot size
~ 70 lakh INR
~ 8 lakh INR / year

11. “
”
ADVANTAGES OF EXCIMER LAMP DEVICE
• NO HEATING TIME
• POWERFUL
• NO CONSUMABLES
• TRANSPORTABLE

12. “
”
CLINICAL RESULTS FOR VARIOUS
INDICATIONS

13. “
”
308 nm, Best wavelength to treat Vitiligo, Psoriasis
&Alopecia Areata
More than 200 clinical studies published

14. CLINICAL INDICATIONS
Presentation title 14
Other conditions-
Lichen planus
Prurigo nodularis, localized
Scleroderma, genital lichen sclerosus
Granuloma annulare
Pityriasis alba

15. CONTRAINDICATIONS
Presentation title 15
Photosensitive conditions such as
• lupus erythematosus
• xeroderma pigmentosum
• History of cutaneous malignancies
• Patient on arsenic or ionizing radiation therapy
• Patient on photosensitizing drugs

16. ADJUSTABLE THERAPIES
16
Excimer combined with
with topical/ oral
treatment
Excimer combined with
with devices
To fasten the results
• Corticosteroids
• Immunosupressors(tacrolimus)
• Minoxidil
• JAK inhibitors (ruxolitinib..)
• Daivobet
• Vaseline with salicylic acid
• Anti oxidants (superoxide
dismutase..)
Combination with CO2laser to treat
resistant patches of Vitiligo.
EXCIMER AS
MONOTHERAPY

17. ADJUSTABLE THERAPIES
17
In case of localized disease : <
: < 10% of the body surface
In case of spread disease : > 10% of
10% of the body surface
Treat with excimer,
• To protect the healthy skin
• To reduce the cumulative dose(less session
session needed)
Excimer
• To treat resistant patches
• To faster treat visible areas
• To treat narrow areas
Conventional phototherapy to exposeat the same
same time most lesions

18. Minimal Erythema Dose(MED) calculation-Very
important.
• 6 Dose testing with
50,100,150, 200, 250
&300mJ doses on
back
• Call patient back or
ask for photos after
24,48 & 72 Hrs.
• Reading done 24 hrs
later->MED= lowest
dose that generates
homogenous
erythema
18

19. Vitiligo Vulgaris
19
• Determine MED
• Start with initial dose based on skin type & location.
• Increase dose every 2 sessions by 50mJ if no erythema seen
after 24 hrs.
• Maintain dose if erythema seen after 24 hrs, but disappears
after 48hrs.
• Reduce dose by 50mJ if erythema lasts between 48-72 hrs.
• Reduce dose by 100mJ if erythema lasts for >72 hrs or blistering
happens.
Vitiligo area Initial
dose(m)/cm2)
Peri-ocular 100
Face and Neck 150
Arm, leg, trunk 200
Elbow, knees 300
Hand, feet 350
Finger, toes 400

20. Vitiligo Vulgaris
20
• Initially-3 Tx per week (non consecutive days) to achieve
trigger healing effect.
• After initial change is seen-›taper to 2 Tx per week.
• Discontinue treatment if no appreciable change is seen in
15-20 sessions.
• Total sessions in vitiligo-15-50, based on response.
• Efficacy depends on location: Face>Neck> Trunk>Lips>bony
prominences>Extremities.
• Combination with Tacrolimus 0.1% &/Or Tofacitinib gives
better & faster results
Post treatment
erythema
Dose
change(mJ/cm2)
No erythema or
<24h
+50
24h <Erythema
<48h
0
48h <Erythema
<72h
-50
72h < Erythema -100
Erythema +++ postpone
nextsession

21. Generalized Vitiligo
• Combined with NBUVB- do twice a week.
• Excimer is used once a week to treat facial vitiligo or exposed areas &
stubborn vitiligo.
• In case if extensive/ unstable vitiligo ->Combine with eitherOral mini
pulse of steroids and/or Azathioprine/tofacitinib
Presentation title 21

22. Segmental vitiligo
• Difficult to treat esp if leuchotrichia is present.
• Response is good if treatment is started early, preferably within6
months of onset.
• Repigmentation is mostly complete and long lasting if treatmentis
started within 1-2 months of onset.
• Combination with topical tacrolimus/fractional laser/MNRF->reduces
number of sessions.
Presentation title 22

23. Acral Vitiligo
• most difficult area-> >60+ sessions.
• Needs pretreatment with Melanocyte-keratinocyte transfer/epidermal
cell suspension.
• Excimer+ topical Tofacitinib - 30 sessions 4 pills (5mg) crushed+ 20 Gm
petroleum jelly.
Presentation title 23

24. Psoriasis protocol
• Determine MED.
• Do 2 sessions per week.
• Start treatment with 1-3X MED
based on severity.
• Increase by 0.5 MED every week,
if no erythema or erythema <24
hrs.
• Maintain dose if erythema
between 24-72 hrs.
Presentation title 24
Post treatment
erythema
Initial dose(xMED)
No erythema or <24h
<24h
+0.5
24h <Erythema <72h
<72h
0
72h < Erythema -0.5
Erythema +++ postpone next session
session

25. Psoriasis protocol
• Reduce dose by 0.5 MED if
erythema > 72 hrs.
• Stay at Max tolerable dose.
• If blistering or crusting
happens -> reduce dose by
1 MED for next 2 sessions->
Then start increasing dose
by 100mJ every 2 sessions.
Presentation title 25
Psoriasis severity Initial dose(xMED)
Mild 1
Moderate 2
Severe 3

26. Alopecia areata
• Start with 50 % MED [max150mj/cm2]
• Increase by 50mj every 2 sessions till
tolerated.
• Stay at this fluence.
• In case of prolonged erythema reduce
by 50mj for next 2session and then
increase again.
• 2 tx per week.
26
Post treatment
erythema
Initial dose(xMED)
No erythema or <24h
<24h
+50
24h <Erythema <72h
<72h
0
48h <Erythema <72h
<72h
-50
72h < Erythema -100
Erythema +++ postpone next session
session

27. Summary
Presentation title 27