During LASIK surgery, your vision may go black temporarily due to the suction ring applied to your eye. This is a normal part of the procedure, as the ring increases intraocular pressure to stabilize the eye while the corneal flap is created. Learn more about why this happens, how it affects your eye, and what it means for your vision.
This blog explains the role of the suction ring in LASIK, the causes of the blackout, and what happens to your retina during this brief phase.
Key Takeaways
- Vision goes black during LASIK due to the suction ring, which temporarily raises intraocular pressure.
- The blackout is normal, lasting up to 35 seconds, depending on the flap creation method.
- The blackout does not cause retinal damage in healthy eyes, as the pressure spike is brief.
- Understanding the blackout can reduce anxiety and help you focus on the benefits of LASIK surgery.
The Role of the Suction Ring in LASIK
The suction ring stabilizes the eye by creating a vacuum, raising intraocular pressure to levels above normal. This pressure ensures the eye doesn’t move while the surgeon creates the corneal flap. Suction pressure typically exceeds 65-90 mmHg, temporarily cutting off blood flow to the retina, causing vision to go black for a brief period. This suction lasts between 10 and 30 seconds depending on the procedure.
Understanding Corneal Flap Creation and Vision Blackout
During LASIK, a thin flap is created on the cornea’s surface. This flap is lifted so the laser can reshape the corneal tissue beneath it. The suction ring temporarily raises eye pressure to stabilize the eye during this process, causing the vision blackout. The two main techniques for flap creation are:
- Microkeratome: A mechanical blade cuts the flap, causing a faster, more intense suction pressure spike, leading to a brief blackout (3-10 seconds).
- Femtosecond Laser: A laser creates the flap with lower suction pressure, but the suction duration is longer (20-35 seconds), resulting in a longer blackout.
What Happens to Your Retina During a Blackout?
The suction ring temporarily cuts off blood flow to the retina by raising eye pressure above retinal arterial pressure. This lack of blood flow causes a temporary blackout, as the retinal cells stop processing visual information. This interruption lasts only for seconds and does not cause permanent damage to the retina in healthy eyes. Blood flow resumes quickly once the suction is released.
Patient Experience During Vision Blackout
Patients report the blackout as a sudden loss of vision, which begins when the suction ring is applied and ends once the flap is created and suction is released. While it can feel alarming, many surgeons prepare patients for this temporary phase to reduce anxiety. No pain is involved, only the sensation of pressure on the eye.
Recovery After the Blackout Phase
The blackout is a normal part of the suction process during LASIK. After the procedure, patients may experience blurry vision, dryness, or sensitivity, but these are different from the blackout itself. Full vision recovery typically occurs over several hours or days as the eye heals, with no long-term effects from the blackout phase.
Risks and Safety of Intraocular Pressure Spikes
Elevated eye pressure during suction is safe for healthy eyes and does not cause permanent retinal damage. However, patients with glaucoma or ocular hypertension may be at greater risk. Surgeons take precautions during suction to prevent excessive pressure and ensure patient safety.
Other Causes of Vision Disturbances After LASIK
Vision disturbances post-LASIK may arise from factors such as dry eyes, residual refractive errors, or natural age-related changes like presbyopia. Glare, halos, or night vision disturbances can occur as the cornea heals. Serious complications are rare and unrelated to the temporary blackout during suction.
Summary of Why Vision Goes Black During LASIK
The suction ring temporarily raises intraocular pressure to stabilize the eye, causing a brief blackout. This is normal and essential for accurate flap formation during LASIK. The blackout lasts only seconds and does not cause any permanent damage to the retina in healthy eyes.
Frequently Asked Questions
How long does the vision blackout last during LASIK?
Microkeratome suction causes blackouts of 3-10 seconds, while femtosecond laser suction lasts 20-35 seconds.
Is the vision blackout harmful?
No. The temporary blackout is safe and caused by the suction needed to immobilize the eye for flap creation.
Why does suction raise eye pressure?
The suction ring compresses the eye to hold it steady, increasing intraocular pressure above retinal blood pressure and blocking blood flow.
Will my vision immediately improve after surgery?
Vision often remains blurry for hours as the eye heals separately from the temporary blackout period.
Can people with glaucoma have LASIK?
Patients with uncontrolled glaucoma are at risk and usually advised against LASIK due to pressure spikes during suction.