Nd:YAG LASER Nd:YAG LASER Wavelengths and emissionsWavelengths and emissions

1

Source with a very low absorption coefficient in the tissue

Nd:YAG Nd:YAG (λ = 1064 nm)(λ = 1064 nm) WAVELENGTH WAVELENGTH

2

Nd:YAG

980

808

Therapeutic window

CO₂

Biological effects Emitted energyBiological effects Emitted energy

Tissue heatingTissue heating

The energy density or fluence (J/cmThe energy density or fluence (J/cm22) is the energy per unit area) is the energy per unit area

I (W/cmI (W/cm22) x t (s)) x t (s)

Nd:YAG Nd:YAG (λ = 1064 nm)(λ = 1064 nm) EFFECTS EFFECTS

3

Continuous emissionContinuous emission

Chopped emissionChopped emission

Pulsed emissionPulsed emissionPowerPower

TimeTime

TimeTime

PowerPower

Continuous: the average power is equal to the peak power.Chopped: pulse duration ton is comparable to the period T.

Pulsed: the average power is far lower than the peak power.

PowerPower

TimeTime

Nd:YAG Nd:YAG (λ = 1064 nm)(λ = 1064 nm) EMISSION MODALITY EMISSION MODALITY

4

Continuous emissionContinuous emission

Chopped emissionChopped emission

Pulsed emissionPulsed emission

In order to avoid thermal damage, emissions are In order to avoid thermal damage, emissions are characterized by low intensities for long times: characterized by low intensities for long times:

Low Efficiency!Low Efficiency!

Fluence (J/cm2): I (W/cm2) x t (s)

Nd:YAG Nd:YAG (λ = 1064 nm)(λ = 1064 nm) EMISSION MODALITY EMISSION MODALITY

5

Excessive thermal increase is avoided thanks to pulses Excessive thermal increase is avoided thanks to pulses with very high intensity and very short duration:with very high intensity and very short duration:

High Efficiency!High Efficiency!

Fluence (J/cm2): I (W/cm2) x t (s)

Countinuous emissionCountinuous emission

Chopped emissionChopped emission

Pulsed emission Pulsed emission (Hilterapia only)(Hilterapia only)

Nd:YAG Nd:YAG (λ = 1064 nm)(λ = 1064 nm) EMISSION MODALITY EMISSION MODALITY

6

CW:• Pm = 1,5 W• Spot = 0,3 cm2

• Fluence in 10 s = 50 J/cm2

• Incident Intensity = 1,5 W / 0,3 cm2 = 5 W/cm2

PW:• Pm = 1,5 W• Spot = 0,3 cm2

• Fluence in 10 s = 50 J/cm2

• Pp = 1500 W • τ-on = 100 μs • Freq.= 10 Hz • Pulse Incident Intensity = 1500 W / 0,3 cm2 = 5000 W/cm2

The Intensity of incident radiation is 1000 times higher in pulsed system respect to continuous system!!

The Intensity of incident radiation is 1000 times higher in pulsed system respect to continuous system!!

Comparison between Comparison between continuous and pulsed systemscontinuous and pulsed systems

7

8

Tempo

Pow

er

Pm=Pp

Time

Pp

Pm

Pow

er

Pm

Pp

ton

toffP

ower

Time

CW Emission

CW-I Emission

PW Emissione

• Diode Laser 632,780, 810, 980, 1064 nm

•Pulsed Nd:YAG 1064nm (only Hilterapia®)

Comparison CW/CW-I emission and Hilt®

CW- I:CW- I:• Pm = 10 W• Spot = 0,2 cm2

• Time = 10 sec• Energy = 100 J• Pp = 20 W • τ-on = 10 ms • Freq = 50 Hz

CW:CW:• Pm = 10 W• Spot = 0,2 cm2

• Time = 10 sec• Energy = 100 J

HILTHILT®® PULSE SH1 : PULSE SH1 :• Pm = 6 W• Spot = 0,2 cm2

• Time = 10 sec• Energy = 60 J• Pp = 1000 W • τ-on = 150 μs • Freq = 40 Hz

HILTHILT® ® PULSE HIRO 3.0: PULSE HIRO 3.0:• Pm = 10 W• Spot = 0,2 cm2

• Time = 10 sec• Energy = 100 J• Pp = 3000 W • τ-on = 120 μs • Freq = 28 Hz

• Intensity= 10W/0,2 cm2 = 50 W/cm50 W/cm2 2

• Intensity =20 W/0,2cm2 = 100 W/cm100 W/cm2 2

• Intensity=1000 W/0,2 cm2 =5000 W/cm5000 W/cm22

• Intensity=3000 W/0,2 cm2 =15000 W/cm15000 W/cm22

9

HilterapiaHilterapia®®

Technical characteristicsTechnical characteristics

10

HilterapiaHilterapia®®

Patented in USA (U.S. Patent n°6,527,797 B1)Patented in USA (U.S. Patent n°6,527,797 B1)

Approved by FDA-USA 510 (k) n. K051537Approved by FDA-USA 510 (k) n. K051537

11

INTENSEINTENSE DEEPDEEP SAFESAFE

Unicity of HilterapiaUnicity of Hilterapia®®

12

HilterapiaHilterapia®®: why?: why?

Because pulsed technology is able to increase the intensity of incident radiation without increase the total quantity of energy delivered to the tissue, with consequently:

Deeper action, high peak power promote penetration inside the tissues

Elevated efficacy, due to the ability of producing biological effects even in deep tissues.

Higher safety of treatment (to minimize risk of thermal damage during laser treatment).

13

• Nd:YAG source (λ = 1064 nm)

• Pulsed emission

• Very high peak power (1-3 KW)

• Veru high intensity (5000-15000 W/cm2)

• High energy content (150-350 mJ)

• Short duration (120-150 µs)

• Low repetition frequency (10-40 Hz)

• Duty cycle 0,1 % - 0,6 %

TECHNICAL CHARACTERISTICS of HILTERAPIATECHNICAL CHARACTERISTICS of HILTERAPIA® ®

14

Vertical delivery of Vertical delivery of energy!energy!

High peak power pulse, up to 3 kW

Short duration (120-150 µs) and long pulse interval (ms)

PowerPower

TimeTime

15

Low frequency: 10-40 HzLow frequency: 10-40 Hz

Low frequencies minimize damaging thermal effects It is known that many cell types are more responsive to low frequency stimulations

PowerPower

TimeTime

16

High energy contents delivered in dephrespecting thermal relaxation time of tissues

LASER PULSATO

17

HILTERAPIAHILTERAPIA®®

Laser-Tissue InteractionLaser-Tissue Interaction

18

HILT PULSE

PHOTOTHERMAL INTERACTION:

•Increase of kinetic energy•Localized increase of temperature

•Formation of temperature gradients

PHOTOTHERMAL INTERACTION:

•Increase of kinetic energy•Localized increase of temperature

•Formation of temperature gradients

PHOTOMECHANICAL INTERACTION(resulting from photothermal effect):

•Temporary deformation of ECM (extracellular matrix)•Reorganization of cellular cytoskeleton•Induction of specific intracellular signals

PHOTOMECHANICAL INTERACTION(resulting from photothermal effect):

•Temporary deformation of ECM (extracellular matrix)•Reorganization of cellular cytoskeleton•Induction of specific intracellular signals

19

ACTION ON CELLS OF CONNECTIVE TISSUES:

• Induction of cell differentiation (maturation process in which cells specialized themselves to perform the characteristic function of the tissue

they belong to) observed in chondrocytes and stem mesenchymal cells.

• Exaltation of inflammatory cytokines signaling pathway, promoting reparative, regenerative and remodeling processes in tissue

• Increase of ECM production by fibroblasts and chondrocytes

• Induction of formation of very ordered arrays of fibronectin fibrils. Fibronectin is a protein that connects ECM components each other and with

cell surface and constitutes a template for collagen fibres assembling.

ACTION ON CELLS OF CONNECTIVE TISSUES:

• Induction of cell differentiation (maturation process in which cells specialized themselves to perform the characteristic function of the tissue

they belong to) observed in chondrocytes and stem mesenchymal cells.

• Exaltation of inflammatory cytokines signaling pathway, promoting reparative, regenerative and remodeling processes in tissue

• Increase of ECM production by fibroblasts and chondrocytes

• Induction of formation of very ordered arrays of fibronectin fibrils. Fibronectin is a protein that connects ECM components each other and with

cell surface and constitutes a template for collagen fibres assembling.

20

ACTION ON ENDOTHELIAL CELLS :

• Promotion of ordered cell monolayers formation, with important consequences on angiogenesis (formation of new vessels) and on endothelial

function (in particular, blood-tissue exchange)

ACTION ON ENDOTHELIAL CELLS :

• Promotion of ordered cell monolayers formation, with important consequences on angiogenesis (formation of new vessels) and on endothelial

function (in particular, blood-tissue exchange)

21

ACTION ON NERVE FIBERS :

• Action on conduction mechanism of peripheral nerve fibers, inducing a dose-dependent reduction of action potential.

• In soft tissue can decrease sensitivity to pain

ACTION ON NERVE FIBERS :

• Action on conduction mechanism of peripheral nerve fibers, inducing a dose-dependent reduction of action potential.

• In soft tissue can decrease sensitivity to pain

22

HILT PULSE

PHOTOTHERMAL INTERACTIONPHOTOTHERMAL INTERACTION

PHOTOMECHANICAL INTERACTIONPHOTOMECHANICAL INTERACTION

ACTION ON CELLS OF CONNECTIVE TISSUESACTION ON CELLS OF CONNECTIVE TISSUES

ACTION ON ENDOTHELIAL CELLS

ACTION ON ENDOTHELIAL CELLS

ACTION ON NERVE FIBRES

ACTION ON NERVE FIBRES

THERAPEUTIC EFFECT •REPARATIVE, REGENERATIVE, REMODELING EFFECT

• ANTI-INFLAMMATORY EFFECT• ANTI-OEDEMA EFFECT

• ANTALGIC EFFECT

THERAPEUTIC EFFECT •REPARATIVE, REGENERATIVE, REMODELING EFFECT

• ANTI-INFLAMMATORY EFFECT• ANTI-OEDEMA EFFECT

• ANTALGIC EFFECT

23

HILTERAPIAHILTERAPIA®®

Indications, contraindications Indications, contraindications

and warningsand warnings

24

Acute pathologies• Tendinopathies• Muscle lesions• Distortions and dislocations• Post-traumatic edemas• Synovitis and bursitis• Osteochondral lesions

Degenerative and chronic pathologies• Osteoarthrosis• Degenerative chondropathies• Fibromyalgia syndrome

THERAPEUTIC INDICATIONSTHERAPEUTIC INDICATIONS

25

Therapy using the system is contraindicated for those patients who:

• have known sensitivity to the device

• take anticoagulants

• take medication that is known to increase sensitivity to sunlight

• have seizure disorders triggered by light

• are pregnant

• suspected of carrying serious infectious disease and/or disease where

it is advisable to suppress heat or fever

• with hemorrhagic diatheses

• have HIV positive history

CONTRAINDICATIONSCONTRAINDICATIONS

26

The device should not be used:

• over areas of suspicious, potentially or known cancerous tissue

• over areas of active hemorrhage

• over areas injected with steroids in the past 2-3 weeks

• over the thoracic area if the patient is using a pacemaker

• over the sympathetic ganglia

• over the vagus nerve

• over the neck (thyroid or carotid sinus region)

• over or near bone growth centers until bone growth is complete

• over area where analgesia may mask progressive pathology

CONTRAINDICATIONSCONTRAINDICATIONS

27

The device should not be used:

• over anesthetic areas

• over an area of the spinal cord following a laminectomy, i.e., when major covering

tissue have been removed

• on ischemic tissue where the blood supply would be unable to follow the increase in

metabolic demand and tissue necrosis might result

• for symptomatic local pain relief unless a pain syndrome has been diagnosed or unless

etiology is established

CONTRAINDICATIONSCONTRAINDICATIONS

28

WARNINGSWARNINGS

• No direct aim into the eyes of humans or animals

• Patients with an implanted neurostimulation device must not be treated with or

be in close proximity to any shortwave diathermy, microwave diathermy,

therapeutic laser diathermy or laser diathermy anywhere on their body.

Energy from diathermy can cause tissue damage and can result in severe injury or

death, even if neurostimulation system is turned off.

29

•The application on wounds has to be performed at a certain distance to avoid the

spread of bacteria.

• Higher output levels have a greater potential for patient discomfort. Choose a

lower dosage to reduce output or select a frequenced output to decrease patient

discomfort.

WARNINGSWARNINGS

30

1- PHOTOCHEMICAL EFFECT1- PHOTOCHEMICAL EFFECT

2- PHOTOTHERMAL EFFECT2- PHOTOTHERMAL EFFECT

3- PHOTOMECHANICAL EFFECT3- PHOTOMECHANICAL EFFECT

31

CLINICAL EVIDENCES

32

Conservative treatment of low back pain caused by intervertebral disk displacement:Comparison among HILT ®, TENS e NSAID(Zati et al. Medicina dello Sport, 2004, 57: 77-82)

33

60 low back pain patients, divided in 3 groups.Treatment lasted 15 days. 1. HILT, n=20 pts: 10 Tx, 5 Tx/week2. TENS, n=20 pts: 10 Tx, 5 Tx/week3. NSAID, n=20 pts: Ketoprofene 200 mg/d. (15 days)

Clinical tests: Backill and VAS at:• T/0 : before treatment• T/1 : 15 days after T/0 (end of treatment)• T/2 : 45 days after T/0• T/3 : 180 days after T/0

Clinical protocol

34

Results

Total Backill test scoresTotal Backill test scores Backill test – t scoresBackill test – t scores

NSAIDNSAIDHILT

HILT

TENSTENS

35

Results

HILT

Total VAS test scoresTotal VAS test scores VAS test – t scoresVAS test – t scores

TENSTENS TENSTENSHILTHILT HILTHILTNSAIDNSAID NSAIDNSAID

36

Results

VAS score and Backill scoreVAS score and Backill score

scor

esc

ore

scor

esc

ore

TENSTENSHILTHILT NSAIDNSAID TENSTENSHILTHILT NSAIDNSAID

37

• In low back pain Hilterapia® is safe and well-tolerated.

• In short terms we obtained similar results using HILT ®, TENS and NSAIDs.

• While, in mid and long terms HILT ® allows better and longer results than TENS and NSAIDs.

Hilterapia® effects are more long-lasting

Conclusion

38

Hilterapia® for the treatment of calcifying tendonitis of the rotator cuff(Valent A., Benedetti E., Istituti Ortopedici Rizzoli, 2003)

39