Photoablation refers to the process of vaporizing tissue by the use of ultraviolet light. It mainly utilizes an excimer laser, in a short duration, at a wavelength of either 193 or 308nm. The process's precise nature ensures minimal or no damage to surrounding tissue. Besides the commonly used excimer laser, a ruby or ND:YAG laser of a similar power density can be used.
The procedure aims to improve the cornea's ability to focus and bend light. The primary eye disorders that require this type of treatment are:
- Hyperopia - An eye condition that describes the problem of seeing objects clearly when far and blurry when close. It is also known as farsightedness.
- Myopia - The eye condition, also known as nearsightedness, refers to seeing things clearly at a close range rather than at a far distance.
- Astigmatism - An eye problem in which everything seems blurry due to the eye's shape.
Photoablation realigns the cornea to enable proper focusing of light on the retina. It can serve as a better alternative to patients who would not prefer wearing eyeglasses or contact lenses.
Also Known As
- Laser Ablation
Laser ablation can employ any of the following approaches:
- Laser epithelial keratomileusis
- Photorefractive keratectomy
- Laser in-situ keratomileusis
Before the Procedure
Before undergoing the operation, one needs to have a meeting with the ophthalmologist to discuss a few things. The doctor may ask questions about one's medical history to be able to determine eligibility. A patient may not be eligible for surgery if they:
- Are below 18 years
- Have thin corneas
- Have glaucoma or some health issues such as diabetes
- Are pregnant or breastfeeding
- Are undergoing certain medications.
The doctor may carry out an eye exam to measure eye pressure, corneal thickness, and refraction. S/he may also dilate the eyes. It would be essential to understand the dangers and benefits of the procedure before agreeing to it.
When going for an eye evaluation, it is advisable to carry eyeglasses to enable proper reviewing. One may need to avoid wearing contact lenses days before the assessment. Meals and medication may continue as usual unless the doctor advises otherwise.
The process may present some side effects that would prevent one's ability to drive themselves home. Therefore, a patient should organize to have someone pick them from the hospital after treatment.
The operation takes place in an eye hospital. The ophthalmologist will first ensure the patient is in a comfortable position. S/he may clean the eyes with a sterilized cloth to prepare them for treatment. The patient then receives drops of local anesthesia that ensure the process is pain-free.
When using PRK, the doctor will remove some surface epithelial skin to reach the eye's top layer. Using an excimer laser, s/he then directs ultraviolet light on the eye's surface to reshape it. The process may take ten minutes to complete.
In the LASIK approach, the doctor will begin by creating a flap in the cornea. S/he will then reshape the central part of the cornea with an excimer laser. The ophthalmologist will then return the flap in place and end the process.
The LASEK approach differs from LASIK because of the creation of a thicker flap. It addresses refractive errors among patients with significantly thin corneas.
Risks & Complications
Laser ablation, as with other forms of surgeries, comprises risks and after-effects. One risk that a patient is likely to experience is the loss of the best correctable eyesight. It refers to the highest level of vision one had while using eyeglasses or contact lenses.
The side effects that one may experience include:
- Sensitivity to light
- Hazy vision
- Eye dryness
- Decreased vision
- A feeling of a foreign object in the eye
- Halos and glare
Aftercare & Recovery
The ophthalmologist may prescribe eye drops to keep the eye moisturized and to prevent infection. The patient should use it as instructed. The doctor may also install a bandage lens to the patient's eye to be worn for a week. The lens allows for the healing of the cornea.
Patients should be careful not to use eye drops without a doctor's approval. They may also need to refrain from swimming or using hot tubs for close to two weeks. While sleeping, one may need to protect the eyes by covering them using a plastic shield.
Follow up visits to evaluate progress are essential. For photoablation, the first visit is usually the next day. The patient may return for lens removal after a week or as per the doctor's directive.
Patients regain clear vision within a few days with the LASIK approach, whereas healing takes 1 to 3 months with LASEK and PRK. Due to the long recovery period in LASEK and PRK, one may need to use eyeglasses to read and drive at night.
The result of laser ablation is a clearer vision. A high number of patients successfully undergo surgery, and it is only a small number that requires retreatment.