how do laser wavelengths & fibers differ clinically?

Disclosure Thomas M. Proebstle, M.D.

I disclose the following financial relationship(s):

•Consultant/Advisory Board: Sapheon

How do Laser Wavelengths and Fibers Differ Clinically?

Thomas M Proebstle

Thermal Ablation

Heat Delivery Technology and Technique

> 10 years: RF old style (RF-current)

810, 940, 980 nm diode lasers

1064, 1320 nm Nd:YAG lasers

< 5 years: RF-Segmental (conductive heat transfer)

1470 nm diode laser

pressurized overheated steam

New Fiber Tips: spherical, covered, radial

Hb H2O

Covered Fiber Tips ceramics bare fiber tip

metal

radial

Clinical Impact of

Wavelengths and Fiber Tips

for Thermal Ablation?

How gentle can Heat Energy

be delivered to the Vein Wall ?

810, 940, 980 nm diode lasers

1064, 1320 nm Nd:YAG lasers

1470 nm diode laser

Hb H2O

Data from Comparative Clinical Studies on the

Impact of Laser Wavelengths are very limited

Energy Dosing Issue is solved for all wavelengths • Vein wall shrinkage maybe a surrogate marker for

sucessful energy transfer Side Effect Profiles were in the Focus since then • look at vein wall perforation and

treatment related side effects

940 nm vs 1320 nm in vitro Linear Endovenous Energy Density 940 nm: 15 W, 3 mm/s : 45 J/cm 30 W, 3 mm/s : 100 J/cm 1320 nm: 8 W, 1 mm/s : 80 J/cm 5 W, 0.5 mm/s: 100J/cm 1320 nm: no perforation 940 nm: perforation, carbonization

1320 nm 8 W, 1 mm/s control 5 W, 0.5 mm/s control

8 W, 1 mm/s control 5 W, 0.5 mm/s

20 mm 13 mm 8 mm

control 15 W 30 W

940 nm

1320 nm

940 nm vs 1320 nm in vitro Linear Endovenous Energy Density 940 nm: 15 W, 3 mm/s : 45 J/cm 30 W, 3 mm/s : 100 J/cm 1320 nm: 8 W, 1 mm/s : 80 J/cm 5 W, 0.5 mm/s: 100J/cm 1320 nm: no perforation 940 nm: perforation, carbonization

1320 nm 8 W, 1 mm/s control 5 W, 0.5 mm/s control

8 W, 1 mm/s control 5 W, 0.5 mm/s

20 mm 13 mm 8 mm

control 15 W 30 W

940 nm

1320 nm

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 50 100 150 200 250

linear endovenous energy density [Joule/cm]

vein

shrinkage [

%]

1320 nm

940 nm pulse

940 nm cw

RA Weiss, Dermatol Surg (2002) 28:56

RFA 1st generation versus 810 nm Diode Laser

Gentle ?

Clinical Influence of Wavelengths

Proebstle TM, Moehler T, Gül D, Herdemann S. Endovenous treatment of the great

saphenous vein using a 1,320 nm Nd:YAG laser causes fewer side effects than using

a 940 nm diode laser. Dermatol Surg. 2005;31:1678-83.

Bare Fiber

1320 nm less bruising, less induration, less pain and analgesics than 940 nm

Kabnick LS. Outcome of different endovenous laser wavelengths for

great saphenous vein ablation. J Vasc Surg. 2006; 43:88-93.

Bare Fiber

980 nm less bruising compared to 810 nm

Side effects - percentage of affected limbs, median [maximum] duration in weeks 940 nm 30 Watt 1320 nm 8 Watt No side effects 2% 18% minor ecchymosis 81% 2 [ 4] 61% 2 [4] any pain 81% 1.3 [12+] 50% 1.5 [2] analgesics (diclofenac) 67% 0.3 [4] 36% 1 [2] induration along vein 64% 4 [12+] 46% 2 [4] phlebitis or periphlebitis 13% 1 [ 2] 7% 1.4 [2] paresthesia 12% 4 [12+] 14% 1 [3]


metal

radial

Impact of Fiber Tips ?

Clinical Impact of

Wavelengths and Fiber Tips

for Thermal Ablation?

How gentle can Heat Energy

be delivered to the Vein Wall ?

Segmental Ablation versus 980 nm Bare Fiber

Prospective Randomized Trials on Patients´ Recovery

Almeida JI et al. Radiofrequency endovenous ClosureFAST versus

laser ablation for the treatment of great saphenous reflux: a

multicenter, single-blinded, randomized study (RECOVERY study).

J Vasc Interv Radiol. 2009;20:752-9.

Shepherd AC et al. Randomized clinical trial of VNUS ClosureFAST

radiofrequency ablation versus laser for varicose veins.

Br J Surg 2010;97:810-8.

Segmental Thermal Ablation shows faster recovery

compared to 980 nm bare fiber ablation proven by

VCSS and QoL instruments

1470 nm Radial versus Bare Fiber


Schwarz T, von Hodenberg E, Furtwängler C, Rastan A, Zeller T, Neumann FJ.

Endovenous laser ablation of varicose veins with the 1470-nm diode laser.

J Vasc Surg. 2010; 51:1474-8.

Less Bruising with Radial Fiber, also Lower LEED

Durability of results?

1470 nm Radial versus 980 nm Bare Fiber


Doganci S, Demirkilic U. Comparison of 980 nm laser and bare-tip fibre with 1470 nm laser

and radial fibre in the treatment of great saphenous vein varicosities: a prospective

randomised clinical trial. Eur J Vasc Endovasc Surg. 2010;40:254-9.

Less side effects and better VCSS with 1470 nm Radial


metal

radial

How can Fiber Tips impact Side Effects?

cylindrical surface area A = 2 p r * h

surface of the CLF coil:

A = 0.23 cm * p * 7 cm = 5.06 cm²

estim. surface of the laser

emitting part of the radial fiber tip:

A = 0.12 cm * p * 0.2 cm = 0.075 cm²

surface of the laser emitting

section of the bare fiber tip A = p r²

A = (0.03 cm)² * p = 0.0028 cm²



A = 0.23 cm * p * 7 cm = 5.06 cm²



A = 0.12 cm * p * 0.2 cm = 0.075 cm²



A = (0.03 cm)² * p = 0.0028 cm²

factor 25

factor 65



A = 0.23 cm * p * 7 cm = 5.06 cm²



A = 0.12 cm * p * 0.2 cm = 0.075 cm²



A = (0.03 cm)² * p = 0.0028 cm²

factor 25

factor 65

Irradiance (10W) I = 2.8 kW/cm²

Irradiance (10W) I = 0.75 kW/cm²

Energy Flux aprox. 70 J/cm (in 20 s)

„I“ = (70J /20s)/(5.06/7)cm² = o.oo5 kW/cm²

980 nm Bare Fiber vs Metal-Shielded Tip

Consecutive patient cohorts

Prince EA, Soares GM, Silva M, Taner A, Ahn S, Dubel GJ, Jay BS. Impact of Laser Fiber

Design on Outcome of Endovenous Ablation of Lower-Extremity Varicose Veins: Results

from a Single Practice. Cardiovasc Intervent Radiol. 2010 Jun 17. [Epub ahead of print]

Partial Recanalization Rate (average 5 months follow-up) was

11.1% for metal-shielded, 2.3% for bare fiber treated GSVs

Company blames lack of metal tip covering

during first months of production of Fiber Kit

CONCLUSION

DATA on Clinical Impact of Wavelength are rare. With

sufficient energy Dosing any Wavelength can ablate the Vein.

LEED and EFE !

Fiber Tips seem to have Influence on Side Effect Profile

POWER Density

how do laser wavelengths & fibers differ clinically?

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