The RI laser systems for laser drilling

Rob Watkins - BSc (Hons)Research Instruments Business and Sales Manager Head of Training

Microsurgical Laser Systems• Quick and easy tool to affect full or partial zona ablation• Distinct advantages over mechanical and chemical methods• Ever increasing portfolio of applications

What is a Laser ?Wiki Definition

A laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" stands forLight Amplification by Stimulated Emission of Radiation.[1][2] The emitted laser light is notable for its high degree of spatial and temporal coherence – A clear precise light wave

http://en.wikipedia.org/wiki/Laser

White Light & Laser light

LASERLASER

TorchTorch

http://www.olympusmicro.com/primer/java/lasers/diodelasers/index.html

Light, including laser “light” can be generated in a range of wavelengths.

Red (635nm) green (532nm) and Blue Violet (445nm)

Remember that not all wavelengths are visibleRemember that not all wavelengths are visible

Laser & Light WavelengthLaser is near infrared 1480nmPilot laser

Laser applicationsSome laser beams can be focused to very tiny spots, achieving a very high irradiance.

They can be launched into beams of very low divergence in order to concentrate their power at a large distance.

When particular lasers are made using gas chambers etc the output power can be very high indeed. Clinical IVF lasers output is 175-400mW

Power of lasers is expressed as milliwatt mW 1 mW = 0.001 w

Lasers can have high powered focused heat output / irradiation

Or long range...

The Laser Diode CrystalLaser Diode Crystal (as used in clinical IVF)

A laser diode is similar to a light emitting diode (LED), in that it is comprised of a junction between two semiconductors (one positive, one negative) and it emits light.

- Glows bright in response to an electrical current being passed through it- The crystal size defines the resonance and

thus the wavelength- It is the coherence that gives thistype of laser its ability to ablate the zona

Fabri-Perrot type Laser Diode FP-LD

Laser pointer (green)

The Science of LasersThe amount of energy delivered in a single laser pulse is simply theproduct of laser power and the pulse duration. For example, a laser of 400mW fired for a duration of 200μs (which would make a hole in ZP of several μm) delivers 80μJ.

Same laser power Longer exposure200μs(400mW) 400μs(400mW)

If this energy were distributed through a small droplet of media (10 μl), then it would cause an increase in temperature of about 0.002°C.

The Science of Laser for IVF...

Laser energy is not delivered uniformly across the droplet,but tightly focused, and this is what makes the laser useable fordisintegrating ZP.

A certain amount of the energy delivered will raise the temperature of the ZP to the point where it disintegrates. There will also be surplus energy delivered into the area of focus and transferred to the surrounding area.

This surplus energy has the potential to damage surrounding cells. It is therefore desirable to minimise the amount of energy and so reduce this potential for damage

Energy vs Hole size – The quest to reduce the level

of risk from peripheral ablation damage

How it works...

NASA space glass

Dichroic glass refers to a glass containing multiple micro-layers of metals or oxides which give the glass dichroic optical properties.

The main characteristic of this glass is that it has a particular transmitted colour and a completely different reflected colour, as certain wavelengths of light either pass through or are reflected.

Class I laser product: A Class 1 laser is safe under all conditions of normal use. This means the

maximum permissible exposure (MPE) cannot be exceeded when viewing a laser with the naked eye or with the aid of typical magnifying optics (e.g. telescope or microscope).

Unique motorised laser moduleLaser ‘Exclusion Zone’ indicates heat safety zoneVersatile software system – RI Viewer

RI is using everything learned from 12 years of building and selling laser systems to build Saturn 5, the best ever laser system. (with a little help from NASA!)

Saturn 5 replaces the existing Saturn 3 and Saturn Active laser products

Its new Biopsy Mode means that the operator can easily select a line, whether straight or curved, and adjust the frequency and size of holes allowing the system to ablate exactly along the chosen path.

Saturn 5 Active Biopsy ModeCurveCurve Straight

LineStraight Line

Using the Saturn Active™ brand

So how does the laser work?• Water readily absorbs infra-red at 1480nm wavelength. As it absorbs the energy it

heats up. • The laser works by locally heating the zona, which is made up mostly of protein

and water. • The laser is focussed to a spot about 2 microns in diameter.• When the laser is switched on, the temperature at the centre of the beam rises,

and heat starts to be conducted away into the surroundings, so that a hole can be made which is larger than the beam.

• The proteins break down at somewhere around 100-120C, and dissolve into the surrounding media to leave a hole.

• The size of the hole can be controlled by varying the length of time the laser is switched on.

RI Laser Objective• A standard microscope objective is

designed to focus visible light (wavelengths from ~400 to 750nm).

• IVF lasers use infra-red light with a wavelength of 1480nm. Standard objectives will not focus an infra-red beam correctly and much of the power will be lost through reflections within the objective.

• The RI laser objective is designed to focus visible light, but also to focus the infra-red beam at the same plane as the visible light, and to maximise the power transmission for efficient drilling.

• The ideal would be to supply just enough energy to remove a given volume of zona to make a given size of hole.

• A low power and long pulse allows more time for the heat to leak away, so you need to turn the laser on for longer to make up for the loss.

• With a higher power laser you can put more energy in with a short pulse before it has a chance to leak away.

• In other words, a high power laser is more efficient at delivering its energy, so the total heat energy delivered is lower than with a low power laser, and so should minimise the risk of specimen damage.

Additional Components

Applications of Saturn Active™• Laser Assisted Hatching (L-AH)• Polar Body Biopsy• Embryo Biopsy• Trophectoderm Biopsy• Assisted Blastocyst Collapse

Applications of Saturn Active™• Laser Assisted Hatching (L-AH)• Polar Body Biopsy• Embryo Biopsy• Trophectoderm Biopsy• Assisted Blastocyst Collapse

Assisted Hatching• Chemical

– Requires operator skill– Difficult to qualify and accurately repeat– Acidic solution needs thorough washing

• Mechanical– Quick to perform– Increased risk of embryo damage– Difficult to qualify perforation size

• Microsurgical Laser– Precise and accurate– Need for expensive equipment

Partial Zona Ablation

• Minimum 75%• Maximum 90% • Do not breach!

Laser Assisted Hatching

• Partial Zona Ablation

• Assists Blastocyst Hatching

• Quick and easy

Applications of Saturn Active™• Laser Assisted Hatching (L-AH)• Polar Body Biopsy• Embryo Biopsy• Trophectoderm Biopsy• Assisted Blastocyst Collapse

Polar Body Biopsy

• Rapid procedure day 0 or day 1• Not using a resource the embryo will need• Easy to perform• Results turn around in 24 hours within a cycle

Applications of Saturn Active™• Laser Assisted Hatching (L-AH)• Polar Body Biopsy• Embryo Biopsy• Trophectoderm Biopsy• Assisted Blastocyst Collapse

Embryo Biopsy

Embryo Biopsy• Most effective at 8 cell stage on day 3 of treatment

– 1 or 2 cells can be taken without compromising embryo development

• Biopsied cells used for pre-implantation genetic screening of the embryo prior to embryo transfer– Generally accepted limitations due to mosiacism and potential

translocations

• Evidence for value of rapid aneuploidy screen using CGH is rapidly gathering momentum

Applications of Saturn Active™• Laser Assisted Hatching (L-AH)• Polar Body Biopsy• Embryo Biopsy• Trophectoderm Biopsy• Assisted Blastocyst Collapse

Trophectoderm Biopsy

• L-AH Day 3• 2 or 3 ablations

Applications of Saturn Active™

• Laser Assisted Hatching (L-AH)• Polar Body Biopsy• Embryo Biopsy• Trophectoderm Biopsy• Assisted Blastocyst Collapse

Assisted Blastocyst Collapse

Summary of Laser ApplicationsDay 0

Day 1

Day 3

Day 5

Oocyte Polar Body Biopsy

Zygote Polar Body Biopsy

Laser Assisted HatchingTrophectoderm Biopsy

Pre-vitrification Blastocyst Collapse

Energy Output from Laser for 8μm •The energy that was needed to be delivered to make an 8μm hole at 400mW was 76μJ.

•At 300mW the energy was 102μJ. At 175mW theenergy needed was 147μJ, almost twice the amount as at 400mW.

•At all diameters of hole, the lower power laser needed to deliver more energy than the higher power.

MORE POWER IS A BETTER LASER TO A POINT

Summary• Safe, reliable and easy to use• Unique features– Class I laser device– Motorised laser module– Exclusion Zone– User visible pilot laser

• Precise and accurate• Expanding range of clinical and research applications• Essential equipment item

Thank you