Cataract Surgery Can Induce Dry Eye Disease (DED)

Cataract and cataract surgery

Cataract is a condition in which the natural lens in the eye loses its inherent transparency, restricting light from passing through the eye and thereby causing vision loss. In the early stages of the disease, a person may notice slight cloudiness because only a small part of the lens is affected. At this stage, treatment with spectacles is usually recommended to correct the blurry vision. When cataracts develop and severely affect vision, surgery is essential to remove the cloudy lens and replace it with an intraocular lens (IOL) to restore vision.¹

There are three main types of cataract surgery. Depending on the eye’s condition, the center’s facilities and patient’s resources, one of the three is recommended:

• Manual small-incision cataract surgery (MSICS or SICS) can be performed in almost all types of cataracts.²
• Phacoemulsification cataract surgery (PCS) is the most popular surgical method today which uses high-frequency ultrasound waves to crush the cloudy lens.³
• Femtosecond laser-assisted cataract surgery (FLACS) is basically similar to PCS with the advantages of laser beams for incision and automation of some of the surgical steps.⁴

Cataract surgery and dry eye disease (DED)

Cataract surgery is capable of triggering dry eye symptoms due to ocular damage and tear film instability after the operation. The severity of dry eye peaks at day 1 postoperatively and continues for at least 1–12 months following the surgery.⁵

Besides, pre-existing DED is common among cataract patients, with 50-75% affected as both conditions increase with age.⁶ Underlying DED if not being well-addressed before cataract surgery can result in adverse outcomes such as fluctuating vision, refractive misses, worsened DED symptoms, and postoperative infections.⁷

Factors that lead to and worsen dry eye symptoms after cataract surgery include:

Corneal nerve damage: Corneal nerves mediating tear production injure during the operation, leading to decreased tear production and dryness.^{8, 9}

Phototoxicity: Prolonged exposure to microscopes during the procedure can cause damage to ocular cells, including cells that are responsible for secreting mucus and lubricating the eye.¹⁰

Inflammation: Inflammation is a temporary response after surgery, causing a decrease in tear production, dryness and discomfort.¹¹

Medicated eye drops: The use of eye drops during and after the surgery may lead to potentially harmful effects on the ocular surface.¹² These topical medications usually contain preservatives, which are potentially harmful to ocular cells.¹¹

The type of surgery: FLACS is considered to have a higher risk and greater severity for dry eye symptoms than the other two techniques.^{13, 14} In addition, some studies also suggest that incidence of dry eye is higher in SICS than PCS.¹⁵

DED treatment before and after cataract surgery

For those who have had DED before the surgery, it is necessary to optimize treatment approach which include over-the-counter artificial tears as well as prescription eye drops. Patients with other eye diseases such as meibomian gland dysfunction may benefit from pre-operative care, including warm compressors, lid hygiene and treatment of demodex.¹⁶ In addition, treating dry eye both before and after surgery with lubricating eye drops including gels and ointments is believed to help relieve dry eye symptoms, improve vision, and improve overall satisfaction of cataract surgery patients.¹⁷ Patients with severe DED can consider implanting punctal plug, a device inserted into the tear duct to stop tear drainage, maintaining the eye’s stability.¹⁸

For those who are suffering dry eye symptoms after cataract surgery, along with other treatments mentioned above, following measures may be considered:

Preservative-free eye drops: standard care for post-operative contains medicated eye drops. Research has demonstrated that utilizing preservative-free formulations is a beneficial approach.¹⁹

Autologous platelet-rich plasma eye drops: a product that is not only similar to our natural tears in pH and osmolarity, but also contains several healing growth factors to improve moderate to severe dry eye.²⁰

Anti-inflammatory eye drops: some agents have been shown to potentially reduce inflammation on the surface of the eye following cataract surgery.¹⁷

Bandage contact lenses: a form of contact lenses that serves as a therapeutic solution for injured corneas. They act as a temporary protective shield for the cornea, aiding in its healing process. A study has shown that using these lenses after cataract surgery can effectively manage DED since they help stabilize the eye's surface and tear film, speed up the healing of the cornea and decrease inflammation.²¹