Surgery + Technology

SILK
S
mooth
I
ncision
L
aser
K
eratomileusis: The Next-Gen Laser Vision Correction.

Smooth Incision Lenticule Keratomileusis (SILK):

SILK is a form of lenticule extraction refractive surgery similar to SMILE, i.e. to create a thin corneal tissue within the cornea for extraction to help improve visual clarity post- surgery. It is the latest refractive surgery to be introduced into the eye world, offering another alternative option to regain crystal clear vision.

Popular refractive surgeries today include LASIK (which involves creating a corneal flap and correcting myopia with surgical laser, started in 1990), Photorefractive Keratectomy (PRK – an older variation of the current LASIK, which began in 1980), and Implantable Collamer Lens (ICL – involving implanting a special corrective lens implant into your eyes instead of administering laser vision correction that started in 1990) and SMILE (which began in 2008).

These procedures have their pros and cons e.g. higher surgical fees for ICL; slower vision recovery from PRK; dry eyes after LASIK. Are there alternatives to quell patients’ unease? Yes, there is. SILK procedure can help to address them.

How is SILK surgery performed?

SILK is performed using the 2023 released machinery for lenticule extraction, the ELITA Eye by Johnson & Johnson Vision USA, 2023.

ELITA, a generational leap in corneal refractive technology

Integrated blend of advanced technologies delivering exceptional precision and accuracy
SILK: Next generation lenticular procedure with consistently smooth lenticule removal
Outstanding patient outcomes
Highly precise & accurate flap thickness with smooth stromal beds and effortless lifts
CHiME advisor an Artificial Intelligence platform monitors system performance to minimize surgery disruption

Before the surgery can be performed, patients will need to undergo a pre-surgery assessment that will determine the eligibility. This includes adequate corneal thickness (minimum of 500 microns), amount of myopia and astigmatism in the patient’s eyes (maximum myopia of -12.00DS and astigmatism of -6.00DC or less), corneal integrity (any possible signs of abnormal corneal steepening or weakening which will hinder surgery outcome). This is followed by the ophthalmologist’s ocular examination, and preparation of surgery should the ophthalmologist deem the patient fit and well to proceed.

If a patient is able to proceed with SILK, here are the procedure steps that would be taken during SILK surgery:

Patient’s data will be registered into the system of the ELITA machine, which will reflect on the thickness of the lenticule to be extracted
Patient’s eye will be placed under the ELITA machine, where there will be a small, bright light for the patient to gaze upon.
Patient will be told to keep his/her position where the machine cuts the lenticule (this process will take 15 seconds/eye) and create a microscopic 2mm incision for removal of the laser created lenticule.
For the next 10 minutes, the lenticule will be slowly removed by the ophthalmologist through the microscopic 2mm incision.
The cornea will self-reshape and correct the eye after the surgery for clear vision.

Most patients returned with excellent visual recovery, and are very satisfied with the outcome. It has been reported up to 99% are feeling great and will highly recommend this surgical option (positive feedbacks include reasonable pricing with outstanding recovery, lesser frequency of dry eye complications and no forms of discomfort after several weeks).

How is SILK different from LASIK?

LASIK has been dubbed as the “household name” when discussing refractive surgeries to correct myopia and astigmatism. It does complete myopia correction in 10 minutes or less and provides clear vision the next day. However, LASIK carries a flap and improper flap care may lead to possible flap wrinkling which hinders the expected clear vision. SILK, on the other hand, will not cause similar complications as the procedure is flapless; it only creates a 2mm micro-incision on the cornea, thus SILK also has lesser impact to structural strength of the cornea post-op. The table below will compare the differences between LASIK and SILK:

	LASIK	SILK
Introduced in:	1990	2023
Minimum age eligibility	At least 18 years old	At least 18 years old
Range of myopia correction	Myopia: -1.00DS to -10.00DS Hyperopia: up to +3.50DS Astigmatism: up to -3.50DC	Myopia: up to -12.00DS Astigmatism: up to -6.00DC
Surgical procedure duration	10 minutes	10 minutes
Vision recovery duration	1 day	1 day
Technology	Corneal Flap 8.0mm diameter	Flapless 2mm incision only
Possible side effects	Dry Eye Syndrome Infections to cornea Glares and halos Potential wrinkling of LASIK flap due to poor flap care	Lesser dry eyes Advantage: No risk of corneal flap wrinkling Reduced risk of corneal ectasia and dry eyes as flapless

How is SILK different from SMILE?

You will be familiar with the term SMILE (Small Incision Lenticule Extraction) – which is a similar procedure to SILK. They are both lenticule extraction surgical technique for laser vision correction (LVC) that is totally flapless. What are the differences between them?

SMILE by Zeiss technology was first released in 2009.

A form of flapless lenticule extraction technology for LVC, SILK using ELITA machine by Johnson & Johnson Vision, USA 2023 offers the following advancements in lenticule technology:

SILK is designed to use the lowest pulse energy, contiguous laser cut pattern and submicron precision for the control of cutting trajectory. The ELITA laser system is designed to deliver lower energy per pulse compared to other laser systems on the market and produce continuous tissue bridge-free corneal lenticules that are easy to remove to enable faster visual recovery.
The lower the energy, the quicker the visual recovery rate post-op.
It chooses a biconvex lenticule shape where it provides mirror symmetric posterior and anterior lenticular surfaces that are expected to match perfectly after lenticule removal, leading to fewer wrinkles in the Bowman’s membrane layer of the cornea, leading to lesser light scattering and better visual contrast sensitivity. Next, since the corneal stiffness, collagen fiber density and nerve density decrease from anterior to posterior, the biconvex shape is expected to better preserve corneal strength, leading to fast regeneration of corneal nerves and hence less dry eyes.

Summary:

There are benefits and high rates of patients’ satisfaction for modern patients who suffer myopia and astigmatism using the advanced SILK surgery. Dr Natasha Lim is one of the pioneer surgeons in Singapore for SILK surgery, the recent advanced refractive surgery solution for myopia, astigmatism and monovision presbyopia correction. If you are interested, please head to our clinic now for a smooth, painless and wonderful experience with SILK where you can worry less and enjoy high quality vision after the surgery.

Our Eye Centre has in-house LASIK and PRK excimer laser systems and the SILK ELITA system for a full choice of refractive surgery for the correction of all refractive errors, including presbyopia too. We also have our own in-house MOH licensed Ambulatory Day Surgery specializing in Implantable Collamer Lens ( ICL ) for those who are not eligible to undergo laser vision correction.

More than 20 years of experience in Ophthalmology

Internationally renowned pioneer LASIK surgeon for iDesign iLASIK in Singapore

Education

MBBS (UK)
B.MED. Sci (UK)
MRCOphth (Lond)
FRCOphth (Lond)
Medical Director & Senior Consultant
Ophthalmology

Specialisation

iDesign iLASIK
SILK (Lenticule Extraction)
LASIK, PRK
Implantable Contact Lens (ICL)
Cataract Surgery
100% Bladeless Laser Cataract Surgery
Presbyopia Correction

Book an Appointment