Do Blurry Visions and Eye Strain Plague Your Daily Life?
Astigmatism, a common vision condition caused by an irregularly shaped cornea, might be the culprit. Traditional glasses and contact lenses offer correction, but for many, laser vision correction is an alluring option to ditch them permanently. However, with choices like SMILE and LASIK available, making the right decision can seem daunting.
Let’s delve deeper into both procedures, highlighting their strengths, limitations, and suitability for astigmatism correction.
Understanding Astigmatism
Imagine your cornea, the transparent dome at the front of your eye, as a perfectly round basketball, focusing light onto a single point for crisp vision.
In astigmatism, the cornea takes on a more oval shape, resembling a rugby ball. This irregularity or elongation bends light unevenly, creating multiple focal points resulting in blurry or distorted vision at all distances.
Different Types of Astigmatism
It’s crucial to understand the different types of astigmatism to differentiate your specific case:
- Corneal astigmatism:
This more common type arises from an irregularly shaped cornea, the transparent dome at the front of your eye. - Lenticular astigmatism:
This less common type is caused by an irregularly shaped lens within your eye. - Mixed astigmatism:
Refers to a blend of corneal and lenticular astigmatism.
Symptoms of Astigmatism
Symptoms of astigmatism can vary in intensity and include:
- Blurry vision at near, far, or both distances
- Squinting to see clearly
- Headaches
- Eyestrain, discomfort, irritation, and fatigue
- Difficulty with night vision
- Light sensitivity
If astigmatism is suspected, a thorough eye exam with a keratometer by your ophthalmologist is vital for diagnosis, determining the degree and type of astigmatism, and exploring treatment options. They can also conduct a visual acuity assessment and refraction test to evaluate your reading ability at various distances.
What Causes Astigmatism?
The cause of astigmatism is unclear, though it is thought to be present from birth with a possible genetic link. It can also result from eye injuries, scars, or surgeries that harm the corneal surface.
Risk factors include family history, eye problems, thin or scarred cornea, blurry vision at various distances, and prior eye surgeries. Astigmatism can occur at any age without a definite cause.
Laser Vision Correction: Freedom from Astigmatism?
While glasses and contacts effectively manage astigmatism, laser vision correction offers a lasting solution. These procedures directly reshape the cornea, eliminating the need for corrective lenses. However, different techniques cater to specific needs and limitations, necessitating careful consideration when choosing the right one for you.
Two Warriors Enter, One Will Leave… (With Clearer Vision): A Deeper Look at SMILE and LASIK
SMILE (Small Incision Lenticule Extraction) and LASIK (Laser-Assisted in Situ Keratomileusis) are two laser vision correction procedures that combat astigmatism, but they differ in their approaches and details:
SMILE: Precise Lenticule Extraction
This innovative minimally invasive technique creates a keyhole incision in the cornea using a femtosecond laser and then removes a lens-shaped tissue piece (lenticule) from the deeper corneal layer, correcting the curvature and astigmatism.
SMILE’s Advantages:
- Minimal Tissue Removal:
Preserves corneal strength and biomechanics, potentially reducing long-term complications. - Faster Healing:
Patients often experience clearer vision within 3-4 days, offering a quicker return to daily activities. - Reduced Dry Eye Risk:
Less nerve disruption during the procedure minimises chances of post-operative dry eyes, a common LASIK side effect. - No Flap Complications:
Eliminates potential flap-related issues seen in LASIK, which can sometimes lead to displacement or wrinkles.
SMILE’s Limitations:
- Astigmatism Correction Range:
Treats astigmatism up to -5 diopters, making it less suitable for severe cases. - Candidate Age Preference:
Ideally, the cornea’s structure should be stable, limiting suitability for younger individuals with potentially changing corneas.
LASIK: The Established Player
This well-established procedure creates a hinged flap in the cornea using a microkeratome blade or femtosecond laser. An excimer laser then reshapes the underlying tissue, correcting the overall curvature and astigmatism.
LASIK’s Advantages:
- Wider Correction Range:
Treats astigmatism up to -6 diopters, potentially catering to higher degrees of the condition. - Proven Track Record:
Millions have undergone LASIK successfully, demonstrating its efficacy and long-term results. - Versatility:
Corrects not only astigmatism but also nearsightedness and farsightedness, offering a comprehensive solution.
LASIK’s Considerations:
- Flap Creation:
Carries a risk of flap complications, like displacement or wrinkles, requiring immediate attention. - Longer Recovery:
Vision stabilisation takes weeks, with potential pain, temporary visual disturbances, and discomfort during initial healing. - Increased Dry Eye Risk:
Flap creation and tissue ablation can disrupt corneal nerves, potentially leading to post-operative dry eyes. - Potential Weakening of Cornea:
The flap creation might slightly affect the cornea’s biomechanical strength and slightly weaken it.
Choosing Your Champion: A Tailored Decision-Making Process
Both SMILE and LASIK offer effective astigmatism correction, but the optimal choice hinges on your unique needs and preferences:
- Astigmatism Severity:
For mild to moderate cases (up to -5 diopters), SMILE might be ideal. For severe astigmatism, LASIK’s wider range is more applicable. - Desired Recovery Time:
If a quicker return to normal activities is prioritised, SMILE’s rapid healing is a significant advantage. - Lifestyle:
If you lead an active life or participate in contact sports, SMILE’s reduced risk of flap complications could be a deciding factor. - Dry Eye Concerns:
If you already experience dry eyes, SMILE’s minimal nerve disruption minimises potential worsening. - Corneal Thickness:
Thin corneas may not be suitable for LASIK due to flap creation requirements. - Comfort Level:
If minimising post-operative discomfort is a priority, SMILE’s quicker healing time might be preferable. - Overall Health and Age:
Discuss your specific health and age with your ophthalmologist to assess suitability for either procedure.
Beyond the Basics
While the information above lays a strong foundation, consider these factors:
- Higher-Order Aberrations:
SMILE and LASIK focus on basic aberrations. For significant higher-order aberrations, ask about topography-guided ablation. - Visual Demands:
Lifestyle matters. LASIK’s flap might be risky for sports with a high risk of eye injury. Discuss alternatives with your doctor.
Professionals needing clear vision should understand potential residual aberrations. - Cost:
Laser procedures are elective and not usually covered. Expect varying costs based on location, surgeon, and technology. Factor in consultations, tests, and procedure costs. Discuss financing with your ophthalmologist if needed.
Remember:
This article offers general information and is not a substitute for personalised medical advice. It is advisable to consult your ophthalmologist for a thorough assessment to determine the most suitable approach for your individual needs. Your ophthalmologist can address your inquiries, provide detailed explanations of procedures, and clarify any doubts you may have.
With thoughtful deliberation and well-informed decision-making, you can begin a journey towards improved vision and freedom from glasses or contact lenses.
