Laser treatment - notes for patients and professionals

Carbon dioxide lasers

Carbon dioxide lasers operate at a wavelength of 10600 nm (far infrared of the electromagnetic spectrum) and are mainly absorbed by water. The rapid heating achieved with these devices results in vaporisation of 100+/-40 μm of tissue (epidermis), while the surrounding dermis experiences tissue coagulation and heat-induced protein denaturation. Fast pulses limit the risk of thermal damage, although the intensity causes collagen fibres to contract and shorten. A new epithelial surface then grows from the undamaged cells lining hair follicles and sweat gland pores during the next 7 to 10 days. New collagen and new elastin fibres would then be formed in the upper dermis in the subsequent 4 to 6 months. This explains why facial skin (rich in adnexal structures) heals more easily than skin from the neck or other areas with fewer adnexal elements, implying a higher risk of scarring in the latter

Erbium:YAG lasers

Erbium:yttrium aluminium garnet (Er:YAG) lasers operate at 2940 nm (infrared) and their energy is absorbed by water up to 20 times more effectively than carbon dioxide lasers. Thus, an erbium:YAG laser can remove thinner layers of tissue with less thermal damage (but lesser results) and so became an attractive alternative for those with milder ageing, sun damage or wrinkling. Patients treated with an erbium:YAG laser typically experience faster healing (about 1 week) and less erythema than those treated with carbon dioxide lasers. However, less heating leads to less coagulation, so dermal bleeding can obscure the surface during treatment. In addition, multiple passes are needed for erbium:YAG treatment to be effective

The advantages of traditional ablative lasers include:

• Remarkable and long-lasting results
• Fewer treatments needed in order to achieve equivalent (and often superior) results in comparison to non-ablative fractional lasers

The disadvantages of traditional ablative lasers include:

• Ablation of epidermis results in delayed healing, higher risk of infections, permanent hypopigmentation and demarcation lines 
• Longer postoperative care is needed (patient needs to comply)

The advantages of fractional lasers include:

• Quicker recovery time with no long-lasting damage
• Additional long-term wound healing response has been documented
• Specific lasers more effective in case of actinic keratosis , lentigines and melasma

The disadvantages of fractional lasers include:

• Complications rate likely to increase over time as more inexperienced clinicians start to use them
• Patient expectations need to be carefully managed in order to remain realistic
• Expensive devices, with a continuous turn-over, often provided on lease contracts which bind the clinician and prevent them from acquiring a new one
• Relatively new field: less data available when compared to traditional ablative lasers

History of fractional lasers

In 2004, Manstein described using a 1550 nm erbium fibre laser to create 1.5 mm deep cylinders of destroyed skin, which they called microthermal zones (MTZs).

These MTZs act as zones of vaporisation surrounded by healthy tissue, thus allowing collagen remodelling, elastic tissue formation, the long-term replacement of aged dermal tissue with newly deposited collagen and faster healing.

The authors found that any evidence of epidermal and dermal destruction in the MTZ would resolve within days, with no residual damage visible after 3 months.

Moreover, the stratum corneum would stay intact, so their prototype was regarded to be non-ablative.

A wide range of fractional devices are now available, using both ablative and non-ablative impulses.

IPL (Intense Pulsed Light) and LED (Light Emitting Diode) 

Are used for various clinical applications, including hair removal, skin lesion treatment, phototherapy, and more. It is essential to be aware of their characteristics, applications, and potential risks to ensure safe and effective use.

Characteristics of IPL and LED Devices

1. IPL Devices:

   - Produced by xenon or krypton flash-lamps.

   - Emit light in a wide wavelength range of 400-1100 nm.

   - Operate in short bursts rather than continuous waves.

   - Produce non-coherent optical radiation.

2. LED Devices:

   - Utilize solid-state semiconductors.

   - Emit light in a broader range of 200-3000 nm.

   - Can be produced as a continuous wave.

   - Produce non-coherent optical radiation.

Applications of IPL and LED Devices

1. IPL Devices:

   - Effective for hair removal and treating selected skin lesions, such as port wine stains, melanocytic nevi, acne vulgaris, and poikiloderma of Civatte.

   - Use filters to target specific wavelengths for optimal treatment outcomes.

   - Safe for use with patients of skin types I to V for various applications.

2. LED Devices:

   - Widely used in medical lighting, phototherapy, photodynamic therapy, restorative dentistry, and microbiology.

   - Can be used alone or with a topical photosensitizer for specific treatments.

   - Provide a portable and cost-effective alternative to other light sources.

Risks Associated with IPL and LED Devices

1. Skin and Eye Hazards:

   - The main risks are related to the skin and eyes.

   - Skin hazards include heating effects on the epidermis, and eye hazards include potential retinal damage.

   - Risk of photoretinitis from prolonged exposure to LED radiation in the range of 300-700 nm.

   - Proper protective measures, such as cooling the skin and maintaining a safe distance from the eye, are essential.

2. Risk Stratification:

   - International Electrotechnical Commission (IEC) has classified LED devices into four risk groups: exempt, RG1, RG2, and RG3.

   - Risk groups consider exposure time and potential hazards for normal behavioral activity, aversion response, and momentary exposure.

Safety Precautions and Legislative Considerations

1. Importance of Risk Minimization:

   - All staff and authorized users have a duty to minimize the risks associated with optical radiation devices.

   - It is crucial to follow safety protocols, including protective measures and proper training.

2. Legislative Regulations:

   - Various legislation and health and safety regulations cover the risks associated with optical radiation devices, including the Physical Agents Directive 2006, MHRA Guidance 2015, Care Standards Act 2000, and PPE at Work Regulations 1992 and 2002.

Expert Roles in Safety and Compliance

Several roles ensure the safe and compliant use of optical radiation devices:

- Laser protection advisor

- Laser protection supervisor

- Operational laser protection supervisor

- Clinical laser expert

- Authorized user

By understanding the characteristics, applications, and risks associated with IPL and LED devices, you can ensure their safe and effective use. Always follow the guidance provided by authorized professionals and take necessary precautions to protect your skin and eyes during treatments.

Safety - before initiating any treatment involving optical radiation, it is crucial to follow essential steps to ensure safety and effectiveness.

1. Treatment Area and Device Setup:

   - The treatment area should be properly prepared and organized.

   - Ensure the device is in good working condition and calibrated appropriately.

   - Check that all necessary accessories and equipment are readily available.

2. Personal Protection Equipment (PPE):

   - The authorized user must confirm the availability and functionality of all required PPE.

   - Personal protection equipment, such as goggles, gloves, and aprons, must be worn during optical radiation treatments.

   - PPE helps minimize the risk of exposure and ensures the user's safety. An approriate LASER mask must be selected.

3. Personal Responsibility of the Authorized User:

   - The authorized user holds the personal responsibility for delivering safe and effective treatments.

   - They should be knowledgeable about the device, treatment protocols, and safety procedures.

   - Adherence to established guidelines and precautions is essential.

4. Adverse Incident Management:

   - In the event of an adverse incident, the user should take immediate action to ensure safety.

   - Secure the treatment environment or initiate an organized evacuation if necessary.

   - Promptly report any adverse incidents to the Laser Protection Advisor (LPA) for investigation.

5. Reporting and Investigation:

   - The LPA is responsible for investigating adverse incidents related to optical radiation treatments.

   - Detailed written reports are provided to the employer of the user and may be shared with relevant bodies, such as the device manufacturer and statutory regulatory authorities.

   - Reporting incidents helps identify any potential risks and ensures continuous improvement in safety measures.