Dr. Joseph J. K. Ma

Advanced Surface Ablation: ISA®


SMILE, ICL, Other Refractive Options

Eyes Over 40: Need for Reading Glasses

ISA® Customized LASIK

This procedure involves three steps: 1) first, a customized diagnostic analysis of the visual architecture of your eye is obtained, 2) then a flap is created – with ISA® Customized LASIK, this is performed with a femtosecond laser with no blades, and 3) your inner corneal tissue is reshaped with another laser to correct for refractive error.

Step 1: The last phase of your ISA® Customized 13-D Diagnostic Set will be completed with the final measurement of your corneal and visual system architecture. Your diagnostic representation will be validated and then finalized, which allows our Surgeon to determine the ISA® Customized Technique.

Step 2: Using blade-free femtosecond laser technology, a precision corneal flap is sculpted in 3 dimensions according to the ISA® Customized Technique that best suits your refractive error and your corneal and visual system architecture.

Step 3: The ISA® Customized Diagnostic Set is then used to guide the Excimer Laser to definitively reshape the inner corneal tissue. Once reshaping is complete, the surgeon lifts the flap back in place.

Femtosecond Laser Technology

Our Surgeon is one of the first surgeons currently practicing in Canada with pioneering experience in Femtosecond laser technology since the first generation was introduced clinically in 2002. It is an extremely accurate, ultra-fast laser that functions at one quadrillionth (*10-15) of a second that allows tissue to be separated without damaging the surface and surrounding tissue. Our clinic currently uses the most recent and most sophisticated generation of Femtosecond lasers that can now go beyond creating a simple flap.

How Femtosecond Laser Technology Works

This generation of lasers delivers rapid pulses of light through the surface of your cornea to a customized set of pre-programmed depths and positions within the cornea to create a microscopic bubble at each site. The laser moves across your eye creating a layer of microscopic bubbles that connect to form a custom sculpted corneal flap that compensates for natural variation in your corneal thickness, and the shape and size of your eye. This level of customization will also optimize the structural features of the edge of your corneal flap to enhance post-operative flap-adherence.

Benefits to You

• A custom sculpted corneal flap of the optimal thinness and structural configuration for your unique eyes and refractive error enables superior post-operative vision because it will accurately reflect the characteristics of the meticulously reshaped cornea below.

• A thinner more reproducible flap produced by a laser allows for more untouched residual corneal tissue and therefore a more structurally sound cornea compared to a flap created by metal blades, which is the original standard practice. As such a laser flap is safer and better for the health of your eye.

• It allows for a completely blade-free surgical procedure which eliminates complications associated with flap creation using traditional metal blades, such as partial flaps, severed flaps, ocular entry and button holes.

• The unique depth and position of each bubble is pre-programmed by our surgeon to create the optimal flap for your unique eyes ensuring superior results.

• The ability to create an ultra-thin flap compared to what is achievable with metal blades means that patients with thinner corneas may still be candidates for laser vision correction.

• Fewer long term flap-related complications due to enhanced post-operative flap-adherence compared to that achievable with traditional metal bladed flaps.

• The precision of the laser allows for fewer induced aberrations (new visual distortions) to the cornea compared to that achievable with metal bladed flaps.

Excimer Laser Technology

Our Surgeon has had over a decade of experience with more than 7 platforms of Excimer laser technology. Our clinic currently uses two models from the more sophisticated generation of Excimer lasers that allow for various forms of customization beyond the standard treatments.

How Excimer Laser Technology Works

This technology ablates corneal tissue by disrupting molecular bonds to precisely reshape the cornea causing minimal heat and no changes to the surrounding corneal tissue. Excimer laser technology can ablate corneal tissue down to a quarter of a micron (1 micron = 1/1,000 millimetres). Excimer laser technology is so precise that corneal tissue can be remodeled to almost any architectural representation necessary to correct for an individual’s unique refractive error.

There are several different techniques that produce an optimized model of corneal architecture. Depending on your unique eyes, applying a specific model will result in superior post-operative vision. Our Surgeon will make a recommendation about which model will best suit your needs at your ISA® Customized Surgical Consultation.

Customized Subtype Techniques Include:

● Wavefront Guided

● Wavefront Optimized

● Topography Guided

● Scheimpflug Image Guided

Our Surgeon’s depth of experience allows for performing the necessary dynamic refinements to the technique for each of the chosen subtypes in every procedure.

Benefits to You

● Superior corneal modeling allows for minimal removal of corneal tissue, which is healthier and safer for the eye, particularly for patients with thinner than average corneas, larger pupils, or higher prescriptions (levels of refractive error).

● More patients able achieve 20/20 vision than without the use of ISA® Customized Subtype Techniques

● Many patients can achieve vision that is superior to 20/20

● Decreases the risk of night time visual complications such as night-time glare

● Reduces shadow and halo effects

● Reduces need for post-operative re-treatments/enhancements


1. How long will it take to recover?

Recovery time depends on the individual, but most people enjoy clearer vision as soon as the next day and this will continue improving over the next several weeks.

We suggest that each patient take 7 days off from work for a comfortable and relaxed recovery.

2. Are both eyes done on the same day?

Yes, both eyes are typically done one after the other on the same day.

3. Is there a blade involved?

No, this is a completely blade-free procedure!

4. Is the procedure painful?

Our Surgeon will administer anesthetic eye drops at the beginning of the procedure so you will not feel any pain; you will only feel slight pressure during the procedure.

5. Will the flap ever come loose?

There is a risk that a direct eye or facial injury could shift the flap. If you are not in a profession that involves and do not regularly engage in activities that place you at risk for eye or facial injury, then the risk of a flap shift is small.

Our use of the more sophisticated generation of Femtosecond laser technology decreases the chances of a flap shift post-operatively by custom sculpting the flap to the unique variable thickness of your cornea and creating an architecture that is less likely to slip.

6. Which procedure is better, ISA Customized LASIK or ISA Customized Advanced Surface Ablation?

There is no “better” procedure; there is only a procedure that is better suited to your unique needs. Both procedures are safe and both procedures yield excellent results, so the optimal procedure just depends on you. Based on our rigorous proprietary in-depth ISA assessment, our Surgeon will identify and recommend the specific option and relevant parameters that is best suited for your unique needs.

Although visual recovery takes longer, ISA® Customized Advanced Surface Ablation is the safer approach to laser vision correction in some cases and can result in better vision than ISA® Customized LASIK in these patients.