Tears keep your eyes lubricated as well as help to focus light so you can see clearly. An adequate amount of tear production is necessary to protect your eyes from dirt, dust, and infectious microorganisms.
Dry eye arises when there is an inadequate number of tears produced. This can be triggered by natural imbalances or surgical procedures. Cataract surgery may exacerbate previously asymptomatic dry eye. But, fortunately, there are a multitude of effective treatments available.
Prevalence, causes, and risks of dry eye
Dry eye affects more than 7 million Americans, making it one of the most common ocular conditions.
The prevalence of dry eye is higher in patients undergoing cataract surgery, and cataract surgery may exacerbate symptoms.
A recent study found that fewer than 25% of patients had been previously diagnosed with dry eye when they presented for cataract surgery, yet 30% reported at least occasional symptoms.6 The need for an increased awareness of dry eye should be considered both preoperatively and postoperatively.
Dry eye pathophysiology results from either inadequate tear production or tears evaporating too quickly from the ocular surface (or a combination of these). This may be due to Sjogren's Syndrome, lacrimal gland disease or obstruction, or meibomian gland dysfunction, leading to decreased oil secretion and gland atrophy.4 One hallmark of dry eye is the hyperosmolarity of the tear film, suggesting that hyperosmolarity can directly cause cell damage and inflammation, which disturbs mucin-producing goblet cells.1
Dry eye is influenced by a variety of external mechanisms. The aging process itself increases one’s risk as well as common environmental factors such as chemical fumes or cigarette smoke. Systemic medications have also been found to increase the risk such as antihistamines, non-steroidal anti-inflammatory drugs, corticosteroids, or anticholinergic medications.4 Polypharmacy, including patients on multiple glaucoma drops, can worsen dry eye due to excessive exposure to preservatives.
Dry eye after cataract surgery may cause more distress
In addition to pre-existing dry eye, cataract surgery may promote dry eye. The etiology is related to corneal nerve dissection, surface epithelium disruption and ocular surface inflammation.5 There is also an increased risk of uncomfortable symptoms after surgery in patients who frequently use eyedrops containing preservatives. Thus, it is important to limit topical medications, such as topical NSAIDs (especially in dry eye patients), after surgery to prevent corneal inflammation. Other factors such as long exposure to a microscope light and frequent irrigation of the tear film can also lead to goblet cell dysfunction and dry eye disease.5
Preoperative assessments
Prior to cataract surgery, thorough evaluation of the ocular surface should be performed. There are a multitude of stains that can be used in the office to better visualize anterior segment pathology.
Fluorescein is a commonly used dye that is placed in the eye and a cobalt blue light is used to detect foreign bodies or corneal damage. There is minimal risk to the test, which mostly focuses on finding abnormalities in the eye.
Lissamine green is another stain variant that is helpful in diagnosing symptomatic patients who have not yet started to show corneal fluorescein staining results.2 The drops are used in the office as well.
Preoperative treatments
It is recommended that dry eye be identified and optimized prior to cataract surgery.
Treatment may consist of over-the-counter remedies such as artificial tears as well as lid hygiene and warm compresses. In the case of moderate-severe dry eye, medications, such as cyclosporine (Restasis, Cequa) or lifitegrast (Xiidra), may be used. These medications have relatively different mechanisms of action but help to improve signs and symptoms of dry eye in order to optimize the ocular surface prior to cataract surgery. In addition, it may be necessary for patients being treated for dry eye to return for more than one office visit prior to surgery to determine suitability of the prescribed treatment. It is advised that preoperative testing (keratometry, biometry) be performed when the ocular surface is optimized, as imprecise results may be obtained in the case of an irregular tear film.
Preoperative home treatments
Patients suffering from dry eye may self-treat their symptoms from home. A hot compress can be placed on the eye for 5-10 minutes at a time. Alternatively, warming masks may be used – there are several varieties available, some which may be heated in the microwave (e.g., Bruder) and some which have a USB-attachment to control the heat setting (e.g., Dr. Prepare). Patients may also ensure they are practicing eyelid hygiene by removing all traces of eye makeup with cleaning pads and washing their face. Supplements can aid in the production of natural oils from the meibomian glands as well. Omega 3 fatty acids (fish oil) have been proven to increase lubrication in the eye and improve the function of meibomian glands.7
Postoperative assessments and treatments
After cataract surgery, your physician will most likely perform testing to ensure a successful treatment as well as gauge the risk of dry eye symptoms. The fluorescein test can be used post-operatively to determine any disturbance in the cornea or ocular surface. It is common to find surveys being used in the office setting to help physicians grade their patient’s symptoms; examples of these include the Ocular Surface disease Index (OSDI) and Standard Patient Evaluation of Eye Dryness (SPEED) scores.
Topical artificial tears
Patients most commonly are treated with topical artificial tears because they temporarily restore the tear film and provide prompt symptomatic relief. There are many different formulations of tears available; for patients with very sensitive eyes, preservative-free varieties may be best to use.
There are fortified artificial tears, such as Systane (Alcon, Fort Worth TX), that contain demulcents and HP-guar which binds to the hydrophobic tear surface and creates a gel to prevent premature tear back-up.3 This gives the patient a longer lasting effect.
Topical steroids
Topical steroids are commonly used as part of the postoperative eye drop regimen for cataract surgery. However, in the case of dry eye exacerbation, inflammation and discomfort may be treated by an extended course of low-dose topical steroids. Eysuvis was recently FDA approved for short-term treatment of pain and inflammation related to dry eye flare-ups (up to two weeks use).
Prognosis
Overall, cataract surgery has an excellent efficacy and safety profile and can be life changing in how it helps restore patients’ vision and quality of life.
Though the risk of dry eye does not portend a grave prognosis, discomfort, diminished quality of vision, and visual fluctuations can decrease patient satisfaction postoperatively.
The latter point is critical in patients selecting premium intraocular lens products (e.g., multifocal, trifocal).
Patient education
A successful outcome is dependent on how educated the patient is on their pre-existing conditions. Dry eye is a common condition worldwide, but some patients may not be aware of its severity. In some cases, patients with longstanding dry eye may not have symptoms, but when the ocular surface milieu is disturbed during cataract surgery, the condition may decompensate, leading to significant ocular surface disease. This exemplifies the need to identify signs and symptoms of dry eye preoperatively and treat prophylactically—even if patients are mildly symptomatic. In some cases, preoperative dry eye surveys may highlight patient’s symptoms that are related to dry eye, which they may not be aware of!
Dry eye need not be a barrier to successful cataract surgery
Dry eye is a common ocular condition as well as a frequent finding after cataract surgery. To prevent exacerbation of symptoms, there are several clinical tests that can be performed to gauge the risks as well as effective treatments to manage symptoms both prior to and after cataract surgery.
It is important to create an easy-to-follow treatment plan for each patient to manage their ocular surface. The importance of treating dry eye as a chronic condition cannot be underscored. While there are no curative therapies, there are many options that will help significantly improve symptoms over time. Becoming a partner with your patient in their dry eye treatment will both improve symptoms and support successful surgical outcomes and favorable patient satisfaction.
References
- Baudouin, Christophe, et al. “Role of Hyperosmolarity in the Pathogenesis and Management of Dry Eye Disease: Proceedings of the OCEAN Group Meeting.” The Ocular Surface, 11, 4, Oct. 2013, pp. 246–258., doi:10.1016/j.jtos.2013.07.003.
- Cunningham, Derek N., and Walter O. Whitley. “The How and Why of Diagnosing Dry Eye.” Review of Optometry, 15 Mar. 2016, www.reviewofoptometry.com/article/the-how-and-why-of-diagnosing-dry-eye.
- Devgan, Uday. “Dry-Eye Syndrome after Cataract Surgery.” Review of Ophthalmology, 30 Dec. 2005, www.reviewofophthalmology.com/article/dry-eye-syndrome-after-cataract-surgery.
- Golden MI, Meyer JJ, Patel BC. “Dry Eye Syndrome.” StatPearls, 25, Feb. 2021. https://www.ncbi.nlm.nih.gov/books/NBK470411/
- Rushdi Ubeid, Adeeb M. “The Unsatisfied Patient after Cataract Surgery Ocular Surface Disease as a Major Contributor.” Int J Opthalmol Clin Res, 5, 4, 2018, pp. 1-3, doi: 10.23937/2378-346X/1410095.
- Trattler, William B, et al. “The Prospective Health Assessment of Cataract Patients’ Ocular Surface (PHACO) Study: The Effect of Dry Eye.” Clinical Ophthalmology, 11, 7 Aug. 2017, pp. 1423–1430., doi:10.2147/opth.s120159.
- Vimont, Celia. “The Benefits of Fish Oil for Dry Eye.” Edited by Rebecca J. Taylor, American Academy of Ophthalmology, 15 Oct. 2020, www.aao.org/eye-health/tips-prevention/does-fish-oil-help-dry-eye.
