Laser peripheral iridotomy (LPI) is a common, minimally invasive procedure used to manage certain structural conditions within the eye. This outpatient laser treatment is often suggested as a preventative or therapeutic intervention to protect long-term eye health. Understanding the process of LPI can help demystify the experience for patients. This article will break down the mechanics of the procedure, what patients can expect during the surgery, and the necessary steps for recovery.
Defining Laser Peripheral Iridotomy and Its Purpose
Laser peripheral iridotomy creates a microscopic opening in the iris, the colored part of the eye. The primary goal is to improve the circulation of aqueous humor, the fluid that nourishes the eye’s internal structures. This fluid is continuously produced and must drain efficiently to maintain a healthy intraocular pressure (IOP).
LPI is necessary when the eye has a structural configuration known as narrow angles. This occurs where the iris meets the cornea, forming the eye’s drainage angle. If this angle is too narrow, the iris can physically block the path of the aqueous humor, a phenomenon called pupillary block.
By creating this bypass hole, LPI allows fluid to flow directly from the posterior chamber to the anterior chamber. This pressure equalization causes the iris to shift backward slightly, effectively widening the drainage angle. This mechanism prevents the sudden spike in eye pressure that characterizes an acute angle-closure event.
The LPI Procedure: What to Expect During Surgery
The LPI procedure is performed in an office or clinic setting, usually taking less than 20 minutes. Before the laser treatment, the patient receives anesthetic eye drops to numb the surface. Other drops, such as pilocarpine, may be used to constrict the pupil, which thins the iris tissue and makes the target area easier to penetrate.
The patient is seated at a slit lamp microscope. The physician places a specialized contact lens directly onto the eye’s surface using a clear lubricating gel. This lens stabilizes the eye, magnifies the iris, and focuses the laser beam precisely onto the periphery.
The physician uses a YAG laser to deliver rapid pulses of energy to create the tiny opening. During the application, the patient will hear clicking sounds and may see bright flashes of light. Patients may experience a mild pinching or pressure sensation, but the procedure is not painful. Once the opening is created and fluid flow is confirmed, the contact lens is removed, and the eye is rinsed.
Immediate Aftercare and Recovery Timeline
Immediately following the procedure, the eye may feel irritated or gritty, and vision is commonly blurry for a few hours. This temporary blurriness is often due to the preparatory drops and the gel used during the treatment. Patients may also experience mild light sensitivity, which can be managed by wearing sunglasses.
The physician will prescribe anti-inflammatory or steroid eye drops, such as Lotemax, for several days to a week. These drops minimize inflammation caused by the laser energy. Patients must follow the prescribed schedule precisely to support healing and prevent complications.
For the first few days, patients should avoid activities that could raise eye pressure or introduce contaminants. This includes heavy lifting, strenuous exercise, and swimming for at least a week. Most individuals can resume normal, light activities, such as reading or working on a computer, within 24 to 48 hours.
Long-Term Monitoring and Potential Side Effects
A follow-up appointment is necessary, usually within a few days to a week, to measure intraocular pressure and confirm the opening is functioning correctly. A transient increase in eye pressure can occur immediately after the procedure, which is managed with pressure-lowering drops.
While LPI is effective, some rare, long-term side effects may occur. A small number of patients may notice a visual disturbance, such as glare, halos, or a line of light, known as dysphotopsia, caused by the new opening. Placing the iridotomy high under the upper eyelid can help minimize this effect.
In rare instances, the opening created by the laser may close over time due to pigment accumulation or scar tissue, necessitating a repeat procedure. Other infrequent complications include significant inflammation, bleeding from the iris, or accelerated cataract formation. Consistent long-term monitoring by an eye care professional is necessary to ensure the therapeutic effect of the LPI is maintained.