The objective fo the SBK Lasik surgery is to preserve the cornea integrity, through creation of a thin and precise flap and it offers faster, safer and better visual recovery to the Lasik undergoing patients . The new trends and technologies in the Lasik surgery emerge and include the best from the best flap creation attributes and number correction technology. SBK Lasik is familiar to the medical industry also with the name Thin Flap Lasik. When the standard or conventional Lasik involves creation of flap of 130 to 180 microns thickness, the thin flap SBK Lasik technology is developed to result in thinner flaps with 90 to 110 microns precise thickness.
There are a lot of advancements taken place, in over 20 years of period, in the Lasik technology, starting from the Standard Lasik to Customized Lasik that reached today to Advanced Aspheric Lasik. The most advanced technologies in recent years have been launched offering the best and finest flap quality with the technologies called Femtosecond Laser and SBK Lasik for blade free Lasik that ensure to offer much better outcome and prevent the complications too. Among them, Thin Flap Lasik result in good and better strength for cornea after the procedure, as it helps in retaining better ground to perform Lasik correction, by creating very think flaps.
Lasik treatments are different kind and when the affordability is considered as an important factor, one can go for conventional flap Lasik. The only difference between the other procedures with this one is the thickness of flap. In certain cases, where inadequate corneal thickness is the concern, then Think Flap Lasik is the appropriate procedure and so is recommended. When dryness of the eye is concerned, SBK Lasik is the appropriate option and it also reduces the usually possible complications with Lasik.
The overall cost of the SBK Lasik surgery procedure, which includes Thin Flap Lasik and Advanced Aspheric Lasik is about 40,000 INR, for both the eyes.
Tissue Saving Lasik Treatment Plan
Basically the procedure of the Lasik laser surgery involves two steps, first is creation of the flap and second is corneal surface reshaping, towards correction of the refraction number. The technology corrects the problem of farsightedness through shaping the cornea to be steeper and corrects the nearsightedness through flattening the shape of the cornea. Correction of astigmatism is done by smoothing of irregular cornea and reshape into more symmetrical shape.
Why Tissue Saving Treatment is Recommend
When Flap Making step is considered the flap thickness is reduced to 40 to 50 microns tissue saving.
When compared to the standard flap making technology, for about 130 microns to 150 microns, the Ultra Thin Flap making technology with the help to SBK Technology or Femtosecond Bladeless Technology creates flap for about 80 to 90 microns.
Tissue saving plan treatment plan reduces for 20% to correct the number through reshaping the surface of the cornea.
How the Tissue Saving Made Possible?
Tissue saving algorithm, an effective way for minimizing the ablation depth has been employed for laser refractive surgery. It is performed through penetrating high energy pulses of ultraviolet light so that it enables removal of precise amount of 0.25 microns of tissue, at a time. (1 micron = 1/1000 millimeter)
Today, the systems available in the market ideally consume 12 to 18 microns for correction of 1 dioptre of number, to ablate or reshape the stroma, the inner layer of the cornea. This overall consumption can be reduced to 20% to reshape the cornea, using tissue saving treatment plan. At certain instances, reduction of optical zone is made possible and 1 dioptre of number correction is done with corneal tissue of 9 microns.
SBK Lasik Laser Surgery – Benefits
- Results in better vision quality
- Helps to maintain better corneal biomechanics, stability and strength
- Comparatively fewer complications, fewer halos and reduced glare
- Faster recovery and improved vision
- Minimized incidence of dry eye post operation
- Higher myopia levels undergoing Lasik, possibly
- Reduced corneal sensitivity loss
- Thinner corneas possibly undergo SBK Lasik Technology
SBK is now also the best option for Lasik patients with thinner corneas.
What Is SBK?
SBK (Sub-Bowman Keratomileusis) is a thin flap blade LASIK procedure, performed to correct nearsightedness, farsightedness, astigmatism and presbyopia. Conceptually, SBK is considered as a thin flap procedure. The procedure is more precise when combined with wavefront technology towards mapping interior and surface of the eye entirely. SBK is safest, precise and reliable laser eye surgery procedure so far. The key benefit of this procedure is that the cornea gets preserved and integrity is maintained by creation of thin flap. In terms of safety, it is of higher order than other laser eye surgery procedures.
SBK shows better visual and refractive outcomes than the conventional thick flap LASIK surgery. Thicker residual stromal bed, post ablation is important. So, creation of absence of stomal flap or thin stromal flap may maximize the thickness of residual stromal bed and it leaves very little biomechanical impact over the cornea, through corneal integrity preservation compared to the meniscus-shaped thicker flaps, achieved by employing thin flap blade or microkeratome.
SBK and LASIK
SBK, like LASIK laser eye surgery, has been performed so far millions of times in the world. Technically, SBK is a new standard and new version developed for laser eye refractive surgery and it is familiarized as one of the most modern forms of this life changing LASIK surgery. The procedure of SBK is precise, just like its term.
There are also certain risks associated with the SBK, however, those are much reduced compared to LASIK. It is because SBK cuts fewer nerves than LASIK. Complications related to the corneal flap are also much reduced. Thin flap SBK is far better and superior to the procedure of LASIK, in this context, especially. Since the depth of the flap would be much shallow with SBK, the chance of dislodging of flap is much reduced. The same also reduces chance of infection. This risk is comparatively more with the LASIK, especially, during contact sports and when the patient is in outdoors.
The procedure is performed in both the ways, technically, with thin flap blade (or microkeratome) to create flap. When the blade is not used, recovery will be faster. The SBK procedure uses microkeratome to create the flap in the cornea. It is painless and recovery will be quick. It separates the tissues precisely through focused pulses of laser that is enabled to divide the material. The flap is lifted gently so that the underlying tissue is exposed and then the surgeon performs cornea reshaping. The laser allows the surgeon to tailor the corneal flap dimensions, according to the individual case and choice. Ultra-thin corneal flap tissue can be prepared with this procedure. As the laser is well controlled by computer, the thinner flap would be created with greater precision and accuracy. Finally, the surgery is completed with more uniform and regular cornea.
The procedure is painless to the patient. The entire procedure takes only 5 minutes normally, for an eye. The patients experience a little to no discomfort post the procedure. They will be able to obtain fair vision with one to two days.
Step By Step SBK Procedure
1. Pre-Operative Procedure
Initially, several tests are conducted and repeated for verification of the measurements. The process is started with numbing the eyes using anaesthetic eye drops. A mild sedative is offered optionally to the patients. A small eye lid holder is gently placed over the eye, in between the eye lids. It prevents the patient to blink, while the procedure is performed.
2. Preparation of the Cornea
Cornea preparation is started and customized corneal flap is designed and created. The construction is performed very precisely, while improving the visual outcomes and safety.
3. Reshaping the Cornea
In this phase, the flap would be reflected back and then the excimer laser is applied to reshape the cornea. While reshaping the cornea, refractive error is corrected. After completion of this phase, the protective corneal flap would be positioned back in its place. This protective corneal flap acts as a natural bandage and it helps the vision to get more rapidly restored.
After these three phases of SBK advanced LASIK surgery, the refractive error would be correction with additional benefits of nearly immediate visual results and quick recovery.
After the first few hours of the surgery, the vision is expected to be blurry. Following a few hours of the procedure, patient starts experiencing significant and rapid vision improvement. Most of the patients are able to get back to the daily activities and resume to work after one day post operative visit.
Combined LASIK and PRK Benefits
The SBK procedure combines the benefits of both LASIK and PRK. Hence, SBK can be considered as a hybrid procedure that can offer the quicker recovery as good as LASIK and safety as good as PRK. The tailor-made flap in this procedure is superior in its structure compared to the flap created with conventional LASIK procedure.
The procedure involved in the SBK is quite similar to that of the LASIK procedure, with a small difference. The conceptual difference between the two is that in SBK, thinner flap is created compared to the LASIK procedure. During the LASIK surgery, flaps that are made lies in between 120 and 160 microns and whereas during SBK procedure, the flap made would be 110 microns approximately. There is better structural integrity of cornea, with this procedure, as it severs a very little number of collagen fibrils, compared to thick flaps, created with the other procedures.
Why SBK, Rather Than LASIK?
There is a procedural difference between SBK and LASIK. The conventional LASIK makes the flap with the thickness ranging between 120 and 180, whereas with SBK, thinner flaps can be obtained with the thickness in between 90 and 110 microns.
The procedure is suitable for all the patients, who are qualified for LASIK. It covers a wide range of qualifying criteria to undergo the procedure. Refractive error eye patients cannot undergo LASIK, who have thin corneas, and however, it is not a restriction in case of SBK. In addition to that LASIK patients are at more risk of developing dry eye condition. However, the risk of developing dry eye condition is very less in case of SBK. Apart from that SBK results in reduced corneal ectasia rate.
SBK Vs PRK
Both SBK and PRK are different to each other. PRK is preferred when cornea is asymmetric. For instance, the cornea is steepened for more than 1.5 D or if epithelial basement membrane dystrophy is evident. SBK is performed with deeper ablation compared to the PRK. Structurally also it is different from the other procedure. When a study is conducted to discover the differences in terms of long term outcomes after SBK and PRK, there are certain facts discovered. Patients have mild irregularity or asymmetry of cornea. The key difference is that the SBK procedure is interrupted peripherally, but PRK involves ablation centrally for Bowman’s membrane. In PRK, epithelial healing followed by keratocyte migration come under acute phase of 15 to 20 days, as a larger stromal exposure area is covered during the procedure. On an overall, SBK is significantly and statistically better compared to PRK procedure in terms of biomechanical stability.
However, in any case, healing period is shorter in SBK than PRK. So, selection and eligibility of the procedure is done on the basis of various factors and the shape of cornea plays vital role among them.
SBS Vs. LASEK
When SBK is compared with LASEK, corneal wound healing response would be more post the surface ablation procedure compared to the stromal flap techniques. With SBK, visual recovery is faster and better refractive & visual results are obtained compared to LASEK procedure.
Advantages of SBK
- The flap created using thin flap blade and made more precisely, compared to the conventional flap of LASIK. It refers to the fact that correction is performed much closer to the cornea surface, just like the procedure of surface ablation. The structural rigidity can be maintained within the eye with a thinner flap of close to 95 microns, compared to the standard LASIK’s 150 micron thick flap.
- Thin flap creation with SBK leaves stromal tissue at sufficient level and it result in safer excimer laser ablation. It is more applicable to the patients suffering from high to moderate myopia and also reduces the risk of causing keratetasia.
- The procedure allows preserving the flap and eventually less discomfort, visual recovery and minimal haze risks are final results. In addition to that flap thinness preserves the cornea’s biomechanical properties and these results are weakened with the flaps created with conventional LASIK. So, the procedure has the advantages of LASIK procedure and surface ablation procedure as well.
The procedure of SBK is advantageous to both the surgeon and patient for the following reasons.
- Corneal biomechanics weakening is minimized.
- The risk of ectasia is reduced.
- Stability gets bettered.
- Qualify of vision can be bettered.
- Visual recovery is faster than other procedures.
- Fewer aberrations of higher order are occurred.
- Contrast sensitivity is bettered.
- Painlessness is an advantage.
- Lesser sensitivity to light is the result.
- Reduced recovery time helps to resume to the regular activities.
- Better sensitivity to light is achieved.
- Very fewer complications like fewer halos and less glare are occurred after the procedure.
- Much reduced incidence of dry eye after the procedure.
- Loss of corneal sensitivity is reduced.
- Increased thickness of flap is predictable.
- The procedure qualifies more patients to get treated.
- The procedure allows the patients with higher levels of myopia to get treated.
- It allows the patients with thinner corneas to be treated.
- It minimizes the rate of undergoing enhancement procedures.
- The procedure offers comparable safety than other LASIK associated procedures.
- Patients can get back to the daily activities earlier, because of shorter recovery.
- Fewer cases of dry eye
SBK procedure is a surgery and so the side effects of all kinds of surgeries are possible technically.
- When enough care is not taken, it may result in infection.
- When the standards and protocols are not followed it can lead to complications, such as scarring or haze, which can be more intense than LASIK.
- Intraoperative complications, which are technically possible would be free cap, flap folds, flap tear and bubble escape.
- Possible flap related complications are buttonhole, flap straie, uneven bed, wrinkles or short flap.
However the rate of complications is lesser than 1%, according to the studies conducted.
The cost of the SBK procedure is more compared to the LASIK procedure, especially, when it uses Intralase laser to perform the procedure. It usually costs in between Rs 35000 to Rs 45000 depending upon type of treatment plan chosen. It is needless to mention that this cost varies from one laser surgery medical centre to another, as many factors cumulate the total cost of the surgery.
Risks are very few after the SBK laser eye surgery. Complications are extremely rare with this procedure. However, technically possible risks, which were reported by a very few patients are scarring, hazing and other minor surgical complications, post the procedure. The risks and complications can be minimized to a greater extent by careful selection of the eligible candidates, through pre-operative testing. Latest diagnostic technology is used for pre-operative testing.
Who Is Candidate for SBK?
Patient with at least 18 years of age is eligible to undergo SBK surgery. The basic considering factors that determine the eligibility are thickness, refractive error and shape of the cornea. Though you cannot be eligible for LASIK because of thin cornea, there is nothing to worry, as you will be qualified for this procedure.
In A Nutshell
SBK has quickly become one of the most popular and safest laser eye surgery procedures to correct refractive errors, as it is a modern and advanced version of LASIK. The technical advantage with this procedure is the dramatically improved flap method. So, it is simply groundbreaking and positive iteration of the LASIK laser eye surgery procedure. Anyhow, the final decision of suitability of the laser eye surgery procedure is taken by the laser eye surgeon. If you are eligible for both the procedures, SBK could be a better choice to undergo.