As a laser manufacturing company, we are often asked questions related to femtosecond laser surgery in ophthalmology. These questions typically involve the safety and precision of the surgery and the role we play as laser equipment providers. Next, let me introduce femtosecond laser surgery from the perspective of an upstream laser manufacturer.
In the field of medicine, especially in ophthalmic surgery, the application of laser technology has become a revolutionary advancement. Femtosecond laser surgery, as a cutting-edge technology in this field, not only represents a significant leap in medical laser cutting technology but also demonstrates the enormous potential of laser technology in improving surgical precision and safety. As laser manufacturers, we have our own understanding of the development and application of this technology.
In this article, we will delve into the working principles of femtosecond laser surgery, its applications in ophthalmic surgery, and how, as laser manufacturers, we support the development of this field through continuous technological innovation and product optimization. We believe that by sharing our expertise and industry insights, we can help the public better understand this leading-edge technology.
Applications of Femtosecond Laser in Ophthalmic Surgery
Femtosecond laser technology, with its high precision and minimal tissue damage, is leading the innovation in ophthalmic surgery. The application of this technology significantly enhances the safety and effectiveness of surgery. With technological advancements, femtosecond laser has transitioned from the laboratory to clinical settings, becoming a crucial tool in ophthalmic surgery, particularly in the fields of myopia correction and cataract surgery. In addition to improving surgical precision, it optimizes postoperative recovery and visual correction, all aimed at a common goal: providing safer and more effective treatment options for patients through advanced technology.
Application 1: Myopia Correction Surgery
Femtosecond laser vision correction surgery is an innovative ophthalmic treatment. It involves precise control and adjustment of corneal shape, altering the structure and refractive state of corneal tissue. This process entails the precise cutting and reshaping of corneal tissue, aiming to focus light accurately on the macular area of the retina to correct myopia.
In simple terms, myopia laser correction surgery can be seen as “sculpting” a precise “contact lens” on the cornea. This “contact lens” corrects myopia, allowing light to focus correctly on the retina. The main methods include:
SMILE (Small Incision Lenticule Extraction)
SMILE is a modern refractive surgery technique used to correct moderate to high myopia and mild to moderate astigmatism. It gained popularity since 2011 due to its minimally invasive nature and preservation of corneal structure compared to LASIK surgery. In SMILE surgery, the surgeon uses femtosecond laser to precisely cut out a lenticular tissue within the cornea, and then a small incision is made on the corneal surface to remove it.
The main advantages of this procedure include minimal impact on the overall corneal structure, rapid postoperative recovery, and lower risk of complications. Additionally, due to the small incision, patients typically experience more comfort and less discomfort postoperatively. However, this surgery also has some disadvantages. Firstly, it requires high-precision femtosecond laser equipment and experienced surgeons, making it technically demanding. Secondly, the cost of this surgery is generally higher compared to other laser surgeries. Nevertheless, it provides a safe and effective vision correction solution for patients with moderate to high myopia, especially for those unsuitable for LASIK surgery.
LASIK (Laser-assisted In Situ Keratomileusis)
LASIK is a popular refractive surgery that involves the precise cutting of a corneal flap using a microkeratome or femtosecond laser. This step is crucial, as the integrity and thickness of the corneal flap are essential for the success of the surgery. Subsequently, excimer laser is used to finely reshape the deeper layers of the cornea to correct vision. This step is the key part of the surgery, requiring highly specialized techniques and advanced equipment to complete. Finally, the corneal flap is perfectly repositioned to ensure tight adhesion and facilitate postoperative recovery.
The main advantages of LASIK surgery include rapid recovery, high efficacy, and minimally invasive nature. Most patients can quickly regain normal vision after the surgery, significantly reducing dependence on glasses or contact lenses. Although LASIK surgery has a low risk of complications, it is not suitable for everyone, especially for patients with thin corneas or other eye health issues. Some patients may experience symptoms of dry eyes or may be unsuitable for surgery due to thin corneas, requiring regular follow-up examinations.
PRK (Photorefractive Keratectomy)
PRK is a laser surgery used to correct myopia, hyperopia, and astigmatism. As a type of refractive surgery, this procedure involves reshaping the cornea’s surface by using excimer laser directly on the corneal surface to improve vision. The surgical process includes local anesthesia, removal of the corneal epithelium, reshaping the cornea, and natural regeneration and healing of the corneal epithelium.
The main advantage of PRK is its broad applicability, particularly suitable for patients with thin corneas. Compared to LASIK surgery, PRK does not involve creating a corneal flap, reducing the risk of complications related to the corneal flap. However, the main disadvantage of PRK is a longer recovery time and potential for more discomfort and pain postoperatively. Despite this, PRK remains a safe and effective refractive surgery option, especially for patients who are not candidates for LASIK surgery.
LASEK (Laser-Assisted Sub-Epithelial Keratectomy)
LASEK is a laser eye surgery used to correct myopia, hyperopia, and astigmatism. This surgical method is an improvement of PRK and aims to reduce the postoperative discomfort of PRK. In LASEK surgery, a special tool (epithelial separator) is used to gently separate the corneal epithelium, rather than completely cutting or removing it. Subsequently, excimer laser is used to reshape the cornea, and after the surgery, the corneal epithelium is repositioned and naturally heals.
The main advantages of LASEK include its suitability for patients with thin corneas and those not suitable for LASIK surgery. Additionally, LASEK attempts to reduce postoperative discomfort by minimizing the cutting of the corneal epithelium and employing a gentler treatment approach. However, compared to LASIK, the recovery time for LASEK is still longer, and there may be some discomfort postoperatively.
LASEK is particularly suitable for patients with thin corneas or other corneal issues. Despite the longer recovery time, it provides an effective approach to reducing postoperative discomfort and improving vision.
Epi-LASIK (Epipolis laser in situ keratomileusis)
Epi-LASIK combines the advantages of LASIK and PRK, aiming to provide a gentler corneal correction solution. In Epi-LASIK surgery, the doctor uses a special tool (epithelial separator) to gently separate the corneal epithelial layer without fully cutting or removing it. Then, excimer laser is used to reshape the cornea, improving vision. After the surgery,
- (a) Procedure for autologous tissue transplantation. The stent laser cut the disc of matrix tissue, which is then replaced on the same bed and sutured with eight interrupted stitches.
- (b) For BPC hydrogel implants, the removed native tissue from the intervertebral disc is discarded, and BPC hydrogel is used as a replacement. The mattress sutures are then placed to avoid suturing through the hydrogel.
Corneal transplant surgery typically involves replacing damaged or diseased corneal tissue with a healthy donor cornea. Femtosecond laser is primarily used for precise corneal cutting in this process, generating extremely high energy intensity in a very small space with low energy, creating plasma, forming microbubbles in the tissue, and accumulating a large number of microbubbles into microcavities. The tissue is cut relying on the photodisruptive effect formed by the optical breakdown of plasma at the focus of the laser beam. Femtosecond laser excels in fine cutting of corneal tissue, allowing for precise control of cutting depth and shape with a smooth cutting surface. It enables highly accurate cutting for both recipient and donor eyes, meeting various corneal transplantation requirements.
The application of femtosecond laser technology in corneal transplant surgery brings numerous benefits. Firstly, it enables precise cutting, enhancing the fit between the transplanted corneal tissue and the recipient, thereby reducing complications during surgery. Secondly, femtosecond laser technology allows surgeons to tailor individualized surgical plans based on the patient’s specific conditions, improving the success rate and safety of the surgery. Additionally, compared to traditional surgical methods, femtosecond laser significantly reduces damage to surrounding healthy tissues during the procedure, aiding in the patient’s postoperative recovery.
However, the application of femtosecond laser technology also poses challenges. Firstly, the surgical cost increases as femtosecond laser equipment and maintenance costs are relatively high. Secondly, the operation requires a high level of skill from the surgeon, necessitating rich experience and specialized skills.
Femtosecond laser technology is mainly used for refractive surgery at present, but as a new tool, it may have broader prospects in precise ophthalmic surgeries like corneal transplantation in the future, showcasing significant potential in the field of healthcare.
Unique Advantages of Femtosecond Laser Technology
Femtosecond laser technology is renowned for its ultra-high precision and minimal tissue damage. Compared to traditional surgical methods, femtosecond laser allows precise manipulation at the cellular level, reducing uncertainties and risks during surgery. The introduction of this technology not only enhances the success rate of surgeries but also significantly reduces postoperative complications.
The application of femtosecond laser technology in ophthalmic surgery is not just a technological advancement but a medical revolution. Here are several key advantages of this technology:
Ultra-high Precision
Femtosecond laser can precisely cut tissues at the micrometer level, crucial for ophthalmic surgeries where eye structures are intricate and delicate. Compared to traditional lasers, femtosecond laser provides higher control accuracy, allowing surgeons to perform extremely detailed surgical operations.
Minimal Tissue Damage
The unique feature of femtosecond laser lies in its extremely short pulse duration, reducing heat accumulation and damage to surrounding tissues. Being non-contact, femtosecond laser minimizes mechanical pressure on eye tissues, lowering the risk of postoperative inflammation and complications.
Improved Surgical Success Rate
The high precision cutting of femtosecond laser enhances the success rate of surgeries, especially in complex or high-risk ophthalmic procedures. Due to precise surgical operations, femtosecond laser surgeries often result in better postoperative visual recovery.
Reduced Postoperative Complications
The minimally invasive nature of femtosecond laser decreases surgical incisions and tissue damage, lowering the risk of postoperative infections. Because of the precision in cutting and minimal tissue damage, patients generally experience faster postoperative recovery with less discomfort.
Latest Trends and Market Demands of Femtosecond Laser Technology
Initially successful in ophthalmology, short-pulse lasers used were Q-switched Nd:YAG solid-state lasers with pulse durations of a few nanoseconds. Subsequently, femtosecond (fs) lasers emerged as the latest advancement in solid-state laser technology, operating with pulse durations less than 1 picosecond. The low pulse energy required for tissue separation in the femtosecond pulse duration range allows the application of lower pulse energy to separate tissues. The use of a three-dimensional beam scanning system creates continuous cutting planes in tissues utilizing high pulse frequencies ranging from 15 kHz to even MHz.
The application of femtosecond lasers in ophthalmic surgery includes corneal flap cutting, lens surgery, and more. The low pulse energy of these lasers significantly reduces mechanical side effects of optical breakdown. For instance, the cavitation bubble radius produced by a 300-femtosecond pulse with 0.75 microjoules of energy in water is only 45 micrometers, much smaller than nanosecond pulses.
With continuous technological development, femtosecond laser technology is making ophthalmic surgeries more personalized, tailoring surgical plans according to each patient’s specific conditions. The application of femtosecond lasers is expanding beyond ophthalmic surgery, showing immense potential in dermatology, dentistry, and other fields. In dermatology, femtosecond lasers can treat various skin issues such as wrinkles, pigmentation, and acne, ensuring a safer and more effective treatment process with precise energy control and a short pulse duration. In dentistry, femtosecond lasers are used for tooth cutting and cavity treatment, significantly improving diagnostic and treatment efficiency.
Furthermore, the emergence of femtosecond lasers is driving technological innovations in other fields. In microelectronics, femtosecond lasers are employed to manufacture high-precision and high-efficiency electronic devices. In the field of communication, femtosecond lasers are used to achieve high-speed, high-capacity optical communication systems.
In the future, as femtosecond laser technology matures and costs decrease, it is expected to be more widely adopted globally. Its application is likely to expand into various fields, providing convenience and well-being to humanity. Simultaneously, with ongoing research on femtosecond lasers, their application in different areas is expected to deepen, bringing more benefits to human life.
What are the Femtosecond Laser Parameters for Surgery?
As mentioned earlier, the revolution brought about by femtosecond lasers has touched almost every field in ophthalmology, including their core use in various eye surgeries. From softening and cutting key parts to creating edge incisions, each aspect can be performed using a femtosecond laser.
However, from the perspective of laser researchers, creating laser parameters for eye surgeries is relatively straightforward. For example, the Intralase FS used in corneal surgery has a pulse repetition rate of 60 kHz (later upgraded to 150 kHz) and a pulse energy of a few microjoules. The Swiss-made Ziemer LDV has a pulse repetition rate of 1 MHz, with pulse energy exceeding 100 nJ. Meanwhile, for corneal cross-linking, a standard femtosecond laser oscillator with an output of a few hundred milliwatts is sufficient. For cataract surgery, higher pulse energy, typically over 10 uJ, is needed.
The refractive vision correction surgical treatment machine LaserSoft uses a compact design and can generate ultraviolet femtosecond pulses and basic nanosecond pulses. Compared to the Nd:galss used in femtosecond systems currently on the market, the laser material used in LaserSoft (titanium sapphire) has a higher pulse-to-background power ratio; smaller wavelength, resulting in more efficient (multiphoton induction) ) evaporation; due to the wider bandwidth of titanium sapphire, shorter pulses (approximately 100 fs) can be generated, resulting in more efficient evaporation;
From the professional perspective of ultrafast laser manufacturers, we can find that compared to more cutting-edge laser technologies, the indicators of these lasers are not amazing. However, to understand the true value and complexity of these lasers, we need to go beyond mere parameters and delve deeper into their performance and stability in real-world applications. In ophthalmic surgery, even small deviations can lead to serious consequences, so integrating these lasers into surgical systems requires precision optical, mechanical and electronic components to work together perfectly and ensure that these devices must guarantee extremely high Reliability and repeatability, which is a challenge in itself.
What can we provide as a femtosecond laser manufacturer?
Comparison of surgical lasers and HELIOS series high-power solid-state lasers
For the demand for higher laser parameters, our “HELIOS high-power laser” just caters to this trend in the market. HELIOS series lasers have excellent performance in high power output, energy stability and beam quality, making them suitable for a wider range of industrial and medical applications. These lasers not only provide increased cutting, welding and marking capabilities, but also show great potential in applications such as precision machining and medical equipment that require higher power and energy.
HELIOS series femtosecond lasers are near-infrared high-power high-repetition-frequency femtosecond solid-state lasers independently developed by our ytterbium-radium femtosecond lasers. They combine semiconductor direct pumping and chirp pulse amplification technology. They have a flexible parameter range and a fundamental optical center wavelength. It is 1030nm, and the maximum output single pulse energy can meet >2mJ. It has ultra-short pulse width, and the typical pulse width range can be from 200 femtoseconds to 10 picoseconds. This characteristic makes it useful in precision material processing and specific scientific applications. irreplaceable role.
Due to the extremely short pulse width, the laser can significantly reduce the heat-affected zone during processing, thereby significantly improving the processing accuracy and material surface quality. For example, in the field of micromachining, this ultra-short pulse width can achieve high-precision drilling, cutting and etching, providing a powerful tool for fields such as microelectronics, optoelectronics and biomedicine.
At the same time, because of its short pulse width and high energy characteristics, the HELIOS series can generate very high peak power. This high peak power plays a critical role in nonlinear optics applications and some materials processing processes. For example, in the nonlinear optical frequency conversion process, high peak power can improve the conversion efficiency, thereby achieving more efficient frequency conversion. In material processing, high peak power can achieve fast and high-precision processing of hard and brittle materials, such as glass, ceramics, etc.
There is also a relatively hidden but extremely important indicator pulse quality (pulse contrast). In general femtosecond lasers, due to the characteristics of high energy and short pulse width, strong nonlinear effects (such as self-phase modulation, four-wave mixing and stimulated Raman scattering) will occur, which significantly affect the transmission and amplification of the pulse. Self-phase modulation (SPM) is a key nonlinear effect that causes pulse spectrum broadening and may cause changes in pulse shape. Spectral broadening will increase the base of the pulse and reduce the peak power and contrast of the pulse. These nonlinear effects will cause changes in the temporal and spectral characteristics of the pulse, thereby affecting the quality of the pulse. In extreme cases, nonlinear effects may even cause pulse rupture. or optical damage.
In contrast, the HELIOS series has a femtosecond pulse quality (pulse contrast) that far exceeds that of common optical fibers on the market. This is mainly due to the fact that in solid-state lasers, although nonlinear effects also exist, solid-state lasers usually have shorter optical path lengths (cm Working in a gain medium of the order of hundreds of μm or even mm, compared with the extremely small core diameter of optical fiber (10 μm), the working cavity mode of the solid-state laser is in the order of hundreds of μm or even mm, which greatly limits the accumulation of nonlinear effects in principle degree and therefore has clean pulse quality.
The HELIOS series femtosecond laser also has the ability to adjust the wavelength. Through frequency conversion technology or with the AURORA series OPA developed by Ytterbium and Radium, it can output lasers of multiple wavelengths. The conventional range is full wavelength adjustable within 350-2600nm. This feature increases the application flexibility of the laser, allowing it to adapt to a variety of different application requirements. For example, in spectral analysis and chemical reaction research, lasers of different wavelengths can provide more precise measurements and more effective experimental control, while higher power and energy also bring higher transmission efficiency.
However, disadvantages such as higher manufacturing costs, more complex operation and maintenance, and larger size and weight also need to be taken into consideration. In the future, with the continuous advancement of technology and the growing demand for applications, we look forward to our HELIOS series femtosecond lasers playing a greater role in more fields.
Expanding applications of femtosecond
Technological innovation promotes the advancement of medical standards. The application of femtosecond laser technology in ophthalmic surgery promotes the progress of the laser industry. Ophthalmology is undergoing a technological revolution led by femtosecond laser technology, through more advanced pulse energy control and laser focusing accuracy. Improve surgical effectiveness and safety. The application of femtosecond laser has been extended to corneal transplantation and cataract surgery, and the equipment is more integrated and user-friendly. Against the backdrop of an aging population and increasing vision problems, there is growing demand for highly precise and safe eye surgeries. Although femtosecond laser surgery is more expensive, its long-term results and safety make it a better option for most patients.
As the technology matures and costs decrease, femtosecond laser surgery is expected to become more widely adopted worldwide. Advances in technology will allow eye surgery to become more personalized, tailoring surgical plans to each patient’s specific circumstances. In addition, the application of femtosecond laser technology may expand beyond ophthalmology to other medical fields, such as neurosurgery and dermatology.
Continuous research and innovation will further push the boundaries of femtosecond laser technology in the field of ophthalmology and make important contributions to the improvement of the safety and effectiveness of eye surgery worldwide. As a laser manufacturer, Ytterbium Radium Femtosecond will continue to pay attention to market dynamics and technology development trends, and is committed to developing more advanced laser products that better meet user needs.
Through in-depth research and continuous innovation, we will further push the boundaries of femtosecond laser technology in the field of ophthalmology and provide strong support for the safety and effectiveness of eye surgery. As a laser equipment manufacturer, we, Ytterbium Radium Femtosecond, will pay close attention to market dynamics and cutting-edge trends in science and technology, and strive to develop laser products that are more advanced and more in line with the actual needs of users.
The application of femtosecond laser technology in eye surgery demonstrates a perfect combination of technology and medical care. With its unique performance advantages and technological innovation, femtosecond laser is bringing more precise and safe surgical treatment solutions to eye disease patients around the world. It is foreseeable that with the continuous advancement of technology and the expansion of application fields, femtosecond laser technology will play a more important role in more application fields in the future and make greater contributions to human health, welfare and social progress. .
