From time to time, patients may ask you about refractive surgery. Although you should not advise them as to whether they are suitable or not, it can be useful for the optical assistant (OA) to have some understanding of the different types of procedures available. In this article, we will look at some of these options – but first, let’s consider why a patient might be looking into refractive surgery.
Refractive surgery can either be clinically necessary or elective, and the aim is to either correct or improve the patient’s unaided vision. Elective surgery means the patient chooses the surgery with the ultimate aim of not needing to wear spectacles or contact lenses anymore.
Clinically necessary refractive surgery means spectacles or contact lenses may not be a suitable method of correction, and may result in poor visual acuity compared to surgery. This surgery is available on the NHS, whereas elective surgery is not.
There are different methods of refractive surgery available, including removing the crystalline lens and replacing it with an intra ocular lens (IOL) or reshaping the cornea. Let’s now look at some of the most common types of refractive surgery techniques available.
Photorefractive keratectomy
Photorefractive keratectomy – or PRK – was the first type of laser eye surgery for vision correction. In PRK, the corneal epithelium is removed with an alcohol solution, and the cornea is reshaped with an excimer laser. The epithelium repairs itself within a few days after surgery. PRK can correct myopia, hypermetropia and astigmatism.
Laser assisted in situ keratomileusis
With laser assisted in situ keratomileusis – or LASIK – a laser is used to cut a thin flap on the surface of the cornea. The flap is then lifted, and a laser is used to reshape the cornea. The flap is then smoothed back down and sticks to the underlying corneal tissue, and so no stiches are needed. LASIK can correct myopia, hypermetropia and astigmatism.
Laser epithelial keratomileusis
Laser epithelial keratomileusis – or LASEK – is a modification of PRK and combines the benefits of PRK and LASIK. The procedure uses an excimer laser and an alcohol solution to loosen the cornea. Compared to LASIK, the cuts require less precision. However, LASEK is a more invasive procedure that involves a longer recovery period. LASEK may be a better choice for people with thin corneas as it doesn’t involve removing as much corneal tissue as with LASIK. LASEK can correct myopia, hypermetropia and astigmatism.
Small incision lenticule extraction
Small incision lenticule extraction – or SMILE – is a newer development in refractive laser surgery. It only needs a small corneal incision and then a laser system reshapes the cornea to correct the refractive error. SMILE can correct myopia and astigmatism, but not hypermetropia.
Refractive lens exchange
Refractive lens exchange – or RLE – is a type of vision correction surgery in which the crystalline lens is removed and replaced with an artificial intraocular lens. This is the same procedure that is used for cataract patients when their lens is replaced with an artificial lens. Single vision, toric and multifocal lenses are available.
To summarise, this is a selection of some different types of refractive surgery options available to patients. It is important to remember that not all refractive errors can be corrected, and that each case is assessed on an individual basis for suitability.
In next month’s article, we will look at the advantages and disadvantages of each type of surgery, including potential complications.
Sue Deal FBDO R is a practising dispensing optician, ABDO College examiner, senior tutor and supervisor for dispensing opticians. She is also a practice visitor and external moderator for ABDO. She was recently awarded the ABDO Medal of Excellence for her outstanding services to the profession.