Strabismus is a condition where the eyes are misaligned. Strabismus surgery aims to correct this by adjusting the eye muscles. While generally safe, it carries potential risks.
Common Risks and Temporary Effects
Following strabismus surgery, patients often experience temporary side effects. Temporary double vision (diplopia) is common, typically resolving within six weeks. The eye may also appear red or swollen after the procedure. Mild discomfort or pain is expected, usually managed with over-the-counter pain relievers. These effects usually subside within a few days or weeks as the eye heals.
Another common outcome is residual misalignment, meaning the eyes may not be perfectly straight. This can manifest as undercorrection, where some misalignment remains, or overcorrection, where the eyes cross or wander in the opposite direction. A small deviation may not require further intervention and can sometimes improve over time.
Less Frequent but Significant Complications
Some complications are less frequent but more significant, often requiring additional medical attention. Persistent double vision, lasting beyond the initial temporary phase, is a more concerning issue. This can sometimes be managed with prisms or patching, but additional surgery may be necessary.
Significant overcorrection or undercorrection may also occur. These outcomes often necessitate re-operation to further adjust the eye muscles and achieve better alignment. Achieving perfect alignment in a single procedure is not always possible.
Infection of the surgical site is a less common but serious complication. While serious internal eye infections are rare, less severe infections around the eye are more common. Bleeding, such as a subconjunctival hemorrhage, is also possible. This usually resolves on its own, similar to a bruise.
Extremely Rare but Severe Complications
Extremely rare but severe complications can occur. Scleral perforation, an accidental puncture of the eye wall by a suture needle, is one such risk. It can lead to retinal damage.
Retinal detachment, where the light-sensitive tissue at the back of the eye pulls away, is another rare but severe complication. Both scleral perforation and retinal detachment can lead to permanent vision loss if not promptly addressed. Vision loss can also occur due to severe infection or significant hemorrhage within the eye.
The oculocardiac reflex can occur during surgery when eye muscles are manipulated. This reflex can cause a sudden and dangerous slowing of the heart rate, potentially leading to serious cardiac events. In rare instances, this reflex has been linked to cardiac arrest and, in very isolated cases, death.
Factors Affecting Outcomes and Further Treatment
Several factors can influence the outcome and risks of strabismus surgery. Patient age plays a role, with younger patients sometimes having a higher rate of reoperation. The specific type and complexity of strabismus also impact the difficulty of achieving a successful outcome. For example, more complicated forms, such as vertical or torsional strabismus, can be more challenging to correct.
Previous eye surgeries can introduce scarring or altered anatomy, making subsequent procedures more complex and potentially increasing risks. The unpredictable nature of muscle healing and scarring means that long-term alignment can vary. This variability can lead to undercorrection or overcorrection over time.
Multiple surgeries might be necessary to achieve the desired alignment, with reoperation rates varying from 10% to 50% or more, averaging between 20% and 25%. Factors such as large preoperative angles of deviation, far/near incomitance (where the misalignment differs depending on whether the patient is looking far or near), and certain patterns of strabismus can increase the risk of needing additional surgery.