Cataract surgery after laser vision correction – is it possible?

Among those presenting for cataract surgery increasingly include patients who have previously undergone laser vision correction. Such a procedure not only eliminates (or greatly reduces) the visual defect, but also changes the shape of the cornea – in nearsighted people the cornea becomes flatter (the central part of the cornea is flattened), in farsighted people it becomes steeper (a greater curvature is created).

Previously performed laser vision correction is not a contraindication to another eye surgery – cataract surgery.

However, it is important to note that it is imperative that we inform the doctor about the previous procedure. Why? Because in calculating the power of the optical lens that will be implanted in us during cataract surgery, the doctor will use the results of the patient’s examinations from the time before laser vision correction and those he will conduct for the now-planned procedure. If the doctor didn’t know that our eye had already been “repaired” with a laser, he would only use the tests he himself would conduct before the surgery. However, the corneal shape measuring instruments he uses contain shape factors and approximations specific to standard corneas, that is, corneas that have not been previously modified in any way by laser. Therefore, a measurement on an eye that has undergone laser correction could be subject to error.

Comparing examinations from before laser vision correction and current ones will allow us to more accurately match the lens to our individual needs. Particularly important are the examinations of the corneal surface: keratometry and corneal topography (corneal maps). In the simplest terms, it can be said that using the data from before the procedure will help us remain people without a visual defect – and now, on top of that, also without cataracts.

Systems to help you choose the optimal lens for your eye with cataracts

Various systems exist to help select the optimal lens for a cataract-bearing eye that has already undergone laser surgery. State-of-the-art equations for correctly calculating the power of an implantable lens include:

• Double-K
• Hoffer Q
• Haigis-L
• Masket
• Koch and Wang

The Verion system (Alcon), on the other hand, allows the power of an implantable lens to be calculated taking into account past surgeries or existing visual pathologies without the need to provide pre-surgical corneal data. However, it is always a good idea to compare the results of calculations performed by several different methods. Using all the data, it is easier to select the best possible lens for an eye that has already been “repaired.”

So, in case of any doubt, the specialist is there to help:

• The patient’s test results from the time his eye was examined in preparation for laser vision correction
• Current results of the patient’s tests performed in preparation for cataract surgery
• modern corneal topograph
• Verion system (Alcon)
• knowledge of calculation formulas and equations for correct calculation of lens power

Armed with such a large number of tools, the doctor is sure to handle even the most complicated case.

Lenses for the most demanding

In general, it is worth being aware that the power of the implantable lens is a key element in planning cataract surgery.

When a patient has no choice, because he opts for a lens reimbursed by the National Health Service, i.e. a monofocal lens, what this means for him is that he will see clearly either up close or far away – for example, he will be able to drive a car without glasses, but to read a book he will continue to need vision correction with glasses.

If a patient decides to undergo surgery in a private clinic and implant a premium lens – a multifocal lens (trifocal/multifocal or EDOF- extended depth of focus) – in addition to cataract removal, he can count on very good visual acuity for distance, near (35-40 cm) and intermediate distance (60-90 cm). In a private clinic, the specialist will do everything so that after cataract surgery, the patient will no longer need any glasses (except for patients practicing professions that require really sharp near vision – such as a watchmaker, tailor or electronics technician, and who in their work do not reach for magnifying glasses and magnifying glasses or for distance, such as professional drivers, pilots, etc.).

In addition to absolute medical indications, individual patient needs are always taken into account in the calculation of the implantable lens when planning cataract surgery. Therefore, the more information your doctor collects during the interview and examination, the more accurately he will choose a lens for your needs. Just that and more…