Everything There Is to Know About YAG Lasers
A YAG laser is also called an Nd:YAG. It is an abbreviation for Neodymium: Yttrium-Aluminum-Garnet. A YAG laser is a crystal with hemoglobin and water as the absorbing chromophores, with a penetration depth of 10 mm and a wavelength of 1064 nm.
The device performs its functions fiber optically, which means that it generates a beam of free-running and pulsed energy. This pulsing mechanism is very sophisticated, and its potential for heat penetration is even more significant than diode ones. Its 1064nm wavelength is poorly absorbed in water. Still, it gets readily absorbed into different pigments of body tissues like melanin and hemoglobin, which makes it useful in producing coagulation and hemostasis. It helps clear frosting that occurs on the backside of the intraocular lens.
During this treatment, the eye doctor uses a magnifying glass so the beam can be precisely controlled, which makes it reliable and safe. The pupils must be dilated to get a good view of the lens. Throughout the duration of the treatment, the patient sees flashes of light and hears a clicking sound.
History of YAG Lasers
In 1964, Bell Telephone Laboratories developed the first working YAG laser with the CO2 laser hand in hand. In 1960, Theodore Mainman did the successful action of the first functional modality, which was like discovering the long-lost key to a lock. Following this, numerous other types of modalities developed, in which this type of device was one of them.
With old versions of the YAG laser, significant power drop was an issue during the application, which occurred due to heat dissipation in the rod. Various ophthalmic treatments, such as the floater treatment with traditional YAG lasers, have the following limitations: 1. Deficiency of visualization of whole vitreous and essential spatial awareness between retina and lens. 2. Suboptimal power usage. 3. Due to older cooling cavities, the inability to apply a sufficient number of it, thus inconsistency of energy delivery in the entire procedure.
Due to these limitations of the traditional modality, there was the development of a new YAG laser in the form of reliable Coaxial Illumination. This illumination system enables the surgeons with complete visualization of the entire vitreous cavity from the retina to the lens. It occurs by using new contact lenses, which are mild-vitreous. Moreover, different advances have occurred in YAG lasers with changes to its wavelengths, of which Advanced Diode-Pumped Solid-state is one of them.
Indications to Use
Health care professionals may get an indication to use this modality when patients present with certain symptoms. If these symptoms persist, the patient can get adverse effects due to complications. Although the need for this laser modality is limited, health care professionals prefer the application of the device to get their patients cured and have a better lifestyle.
Acute Angle Glaucoma
The pressure rises in the anterior chamber due to sudden blockage of the healthy circulation of fluid within the eye. For this type of glaucoma, the YAG laser is used in surgery to relieve the increased pressure.
The Nd:YAG laser is helpful in periodontal therapy, including bacterial decontamination and saccular debridement. It results in the regeneration of supporting bone, potential new attachments of gingival tissues, and regrowth of periodontal ligament. It also has positive effects on pocket therapy.
Its use can also be in removing birthmarks, wrinkles, and fine lines from the skin. Although this therapy is not cost-effective, it is necessary to remove any carcinoma of the skin.
Minor Oral Surgeries
The properties it contains helps it in its use in a variety of maxillofacial procedures, including but not limited to:
- Arthroscopic operation of the temporomandibular joint.
- Hemostasis in bleeding disorders.
- Palliation of advanced neoplasms.
- Resections in vascular tissues.
- Coagulation of angiomatous lesions.
Treatment of Symptomatic Floaters
Advances in the YAG laser has made it the best in the treatment of symptomatic floaters. Moreover, this procedure offers the possible benefits of a simplified postoperative course. Small floaters, such as amorphous clouds, Weiss rings, and strings, which are not significant to undergo surgery, are treatable with this type of device. Floater treatment is not to compete or replace the vitrectomy procedure by any means. The ideal patient for treatment is very different from a vitrectomy patient.
Laser Therapy in Ophthalmology
After Cataract Surgery
A cataract is a painless condition in which the eye's lens becomes cloudy, causing blurry vision. It occurs in response to the aging phenomenon. Moreover, it is caused by excessive UV light exposure, trauma, or diabetes. A capsulotomy is mandatory for its treatment. Health care professionals prescribe a short course of pressure lowering and anti-inflammatory drops after surgery. Improvement in vision and clarity occurs within a day after this treatment. Such treatments are required seldom in a lifetime because after vaporizing using this modality, the capsule does not regrow.
There are two types of capsulotomy:
In this surgery, the anterior side of the eye capsule is cut down. After the removal of the cloudy lens, a new artificial lens takes its place. This surgery is the best treatment regimen for cataracts, recommended by health care professionals. The cloudy lens is replaced with a plastic lens by anterior capsulotomy.
It is done after cataract surgery to improve vision. Capsular thickening happens after some time with cataract surgery. This thickening makes the vision blur, which is known as posterior capsular opacification or second cataract. YAG laser posterior capsulotomy is the only way to treat this. No special preparations are necessary for this treatment. The doctor recommends two types of drops before surgery. An anesthetic eye drop is essential to dilate the pupil and to numb the surface of the eye.
Treatment of Bladder Tumors by Endoscopy
It determines lesions caused by coagulation necrosis. When observed microscopically, necrosed tissues delimited from the adjacent tissue are seen. With the appearance of a dense fibrous and intense granulation tissue, healing occurs after approximately eight weeks. Transmural coagulation occurs without perforating the walls of the urinary bladder by the high penetration of this modality. In this type of surgery, there is a chance of damage to nearby tissues. After the coagulation of the tumor, it turns white.
It is now available for a millisecond pulse duration and high fluences. The modality with the large pot size is useful in the painting techniques of facial erythema treatment. Smaller pot sizes help treat telangiectasia.
Complications of the YAG Laser
The penetrating depth of this is up to 4mm, making the most significant potential to damage soft and, sometimes, hard tissues in the body. Before using the modality, one must ensure that the device is working properly with no errors to prevent complications related to the device. Various other complications are mentioned below.
In Urologic Surgeries:
The penetration of tissues results in consequent tissue heating and a broad zone of coagulative necrosis or thermal injury of 4 to 6 mm. As the energy density is low in muscles, the warming of the tissue remains more moderate than the boiling point, resulting in coagulative necrosis. The coagulated tissues become white and subsequently sloughs in a period of four to eight weeks. Heat generation occurs continuously, which makes it difficult to predict and control the depth of thermal necrosis.
Near the implants:
This type of modality is unsafe for procedures which are implant-related or for peri-implant surgery as they can melt the surface of the implants. Also, they can remove the top layer from titanium implants, which are plasma coated. This modality also produces craters and cracks on surfaces of titanium. Very rarely, retinal detachment may occur. The chances of retinal detachments are high for cystoid macular edema within five months post-treatment. During this treatment, the anterior vitreous face gets disrupted, which increases the risks and complexity of an intraocular lens exchange.
More complications are:
- Raised eye pressure
- Damaged intraocular lens
- Vitreous floaters
- Retinal swelling
- Epiretinal gliosis
- Macular edema
As a result of YAG laser complications in ophthalmic treatments, femtosecond photo-disruptive modalities are next in line for the intraoperative anterior capsulotomy.
- Power: 100W
- Max pulse energy: 2J
- Pulse rate: 100Hz
- Wavelength: 1.05 µm
- Output power regulations: ±10>#/p###
- Pulse width: 0.1 to 1000 µs
- Input power: 440 V 3 phase, 60 Hz, 20 A/line
- Cooling rate: 9.0-13.5 I/min
- Maximum temperature: 30>#/p###
- System weight: 100kg
- Laser head dimension: 915mm x 178mm x 178mm
A significant player in this sector of medicine is known as Laser Quantum, a world-class manufacturer of devices of the highest quality (e.g., ultrafast modality, diode-pumped solid-state). They are famous for their compactness, long operational lifetime, reliability, and performance-excellence.
Another major manufacturer is Lumenis, a global leader in the field of energy-based equipment in medicine associated with aesthetics, surgical procedures, and eye care.
- Anderson Lasers, Inc.
- Convergent Laser Technologies; a subsidiary of Xintex Corp.
- IB Laser Consulting, Inc.
- Fotona d.o.o.
- Optola - Vilnius, Lithuania
The modality was from the early revolutions after the instrument’s invention in 1960. It has diverse functions in different domains, such as medicine, military, and surgical treatments. It is the first type of modality that has helped in urological practice. Its working machinery consists of three components and works on the mechanism of spontaneous emission. Although its complications are rare, some complications are severe.
Various companies manufacture this modality. This modality has forever revolutionized the way we look at noninvasive surgery. This type of therapy is a need in today's medical field, where health care professionals can make perfect use of it. It has allowed us to do those things we never imagined and to perform unthinkable operations.