What is the cause of a foreign body sensation, like a grain of sand, in the corneal area of the left eye after cataract surgery, which was not experienced during the first operation, in a patient with astigmatism?

From the Guidelines

The sensation of a foreign body or "grain of sand" in the eye after cataract surgery is most likely due to dry eye syndrome, which can be caused by the surgical incision and manipulation during the procedure, and can be exacerbated by astigmatism in the left eye. This feeling is a common postoperative symptom that typically resolves on its own within a few days to weeks. However, individual healing responses can vary between eyes, especially if the patient has astigmatism, which can affect the corneal surface. According to the most recent study on dry eye syndrome preferred practice pattern 1, many ocular surface diseases produce symptoms that are similar to those associated with dry eye, including foreign body sensation, mild itching, irritation, and soreness. Some key points to consider in this case are:

• The patient's symptoms, such as foreign body sensation, are consistent with dry eye syndrome
• The patient's astigmatism in the left eye may be contributing to the development of dry eye syndrome
• The use of preservative-free artificial tears 4-6 times daily can help to lubricate the eye surface and reduce discomfort, as recommended by the study on refractive surgery preferred practice pattern 1
• The patient should avoid rubbing the eye and continue any prescribed post-operative medications such as antibiotic and anti-inflammatory drops according to her surgeon's instructions
• If the sensation persists beyond 2-3 weeks, worsens significantly, or is accompanied by decreased vision, pain, or redness, the patient should return to her ophthalmologist for a follow-up examination to rule out complications such as dry eye syndrome, epithelial defects, or suture-related irritation.

From the FDA Drug Label

Ocular adverse reactions occurring in 5%-15% of patients treated with loteprednol etabonate ophthalmic suspension (0.2%-0. 5%) in clinical studies included ... foreign body sensation, Some of these events were similar to the underlying ocular disease being studied.

The cause of a foreign body sensation in the corneal area of the left eye after cataract surgery may be related to the use of loteprednol etabonate ophthalmic suspension [ 2 ].

• Foreign body sensation is listed as a possible adverse reaction to the medication. However, the label does not provide information on why this sensation was not experienced during the first operation, or how astigmatism may be related to this adverse reaction.

From the Research

Causes of Foreign Body Sensation

• The provided studies do not directly address the cause of a foreign body sensation in the corneal area after cataract surgery.
• However, some studies suggest that dry eye symptoms, which can include a foreign body sensation, are common after cataract surgery 3.
• Punctal occlusion, a treatment for dry eye syndrome, can also cause foreign body sensation as an adverse event 4, 5.
• The use of lubricating drops, including saline, may reduce contact lens discomfort, but the evidence is very uncertain 6.
• Hydroxypropyl guar-hyaluronic acid dual-polymer lubricant eye drops have been shown to be safe and effective in managing dry eye symptoms, including reducing dry eye symptoms post-cataract surgery 3.

Possible Explanations

• Dry eye syndrome, which can be exacerbated by cataract surgery, may contribute to the foreign body sensation.
• The use of punctal plugs or other treatments for dry eye syndrome may also cause foreign body sensation.
• Lubricating drops, including saline, may provide some relief from dry eye symptoms, but the evidence is limited.
• Further research is needed to determine the cause of foreign body sensation after cataract surgery and to develop effective treatments.

Related Symptoms and Treatments

• Dry eye symptoms, including ocular discomfort, visual disturbances, dryness, and itching, are common in patients with dry eye syndrome 3, 7.
• Punctal occlusion, a treatment for dry eye syndrome, can cause adverse events such as epiphora, itching, tenderness, and swelling of lids with mucous discharge, and plug displacement 5.
• Lubricating drops, including saline, may reduce contact lens discomfort, but the evidence is very uncertain 6.
• Hydroxypropyl guar-hyaluronic acid dual-polymer lubricant eye drops have been shown to be safe and effective in managing dry eye symptoms 3.