Although cataract surgery referrals are often routine, identifying certain comorbidities is key to good outcomes. Herpetic eye disease is particularly important due to its frequency and the risk of severe relapses.

A Recent Case

Inspiration for this article comes from comanagement with Dr. Leslie Elms, one of the most outstanding ODs I’ve worked with, as we tried to figure out how to safely and effectively plan the care of her cataract patient—who also had herpes zoster ophthalmicus (HZO).

The patient suffered from chronic inflammatory disease linked to HZO that had recently been brought under control. But we couldn’t ignore the stress of cataract surgery precipitating a relapse. Because Dr. Elms practices two hours from our Boise, Idaho facility, we wanted to minimize unnecessary patient travel.

Comanagement Considerations

Although this patient had HZO, herpes simplex keratitis creates similar risks—and is even more frequently encountered.

Although there is no cookie-cutter approach that works for all patients, let’s review some considerations and general rules of thumb for planning cataract surgery in eyes with previous or active co-existing herpetic eye disease. These patients should not be treated or referred as routine cases, and communication between the primary optometrist and surgery center is crucial.

Herpes Simplex

Herpes simplex virus (HSV) is one of the most common infections, with some studies estimating that 90% of the adult population carries the virus. It frequently affects the eye, often resulting in vision loss from corneal scarring. Due to its widespread distribution and predilection for the eye, herpes simplex is the number one infectious indication for corneal transplant in the developed world.

​“Ghost dendrite”—a scar from a prior dendritic keratitis.

The physiologic and immunologic stress of cataract surgery is enhanced by the universal post-operative use of corticosteroids, which makes reactivation of inactive herpetic disease more likely. Each relapse increases the risk of a visually significant scar.

There are two general forms of herpes simplex keratitis that we need to consider when planning cataract surgery—infectious epithelial keratitis and herpes stromal keratitis.

1. Infectious epithelial keratitis (IEK)

Sometimes referred to as IEK, dendritic keratitis represents the truly infectious manifestation of HSV keratitis. IEK is easily identified by a characteristic dendrite. It’s a true corneal ulcer, and the resolution will result in a scar. The scar is usually superficial and mild. But central or paracentral scars can affect vision.

In preparation for cataract surgery:

• Efforts should be taken to prevent patients with a history of IEK from relapsing.
• Recent episodes should be fully resolved, and patients should wait approximately three months after resolution before proceeding with surgery.
• While the use of antivirals as prophylaxis may vary between surgery centers, I recommend them for anyone who has had an IEK flare-up within 12 months of surgery, or in any case that has resulted in substantial scarring.
• You may choose to use topical antivirals four times per day, but suppression dosing of acyclovir (400 mg bid) or valacyclovir (500mg qd) is more affordable and well tolerated. I generally select orals and start therapy one week before surgery and recommend continuing at this dosage for four weeks after. No adjustments to standard post-operative eye drops are needed.

​Corneal neovascularization resulting from herpetic infection.

2. Herpes stromal keratitis (HSK)

HSK is the most severe manifestation of HSV keratitis and the form most likely to require a corneal transplant. Treatment is combined topical corticosteroids and oral antivirals as prophylaxis. Unlike IEK, which generally resolves even without treatment in around three weeks, HSK duration can be much less predictable and more chronic. Therefore predicting the appropriate timing of cataract surgery can be impossible.

In planning cataract surgery, the same general rules of thumb apply as with IEK:

• Ideally, the episode should be resolved, and the patient should be off the corticosteroid for a few months before cataract surgery.
• Use of prophylactic antivirals leading up to and following surgery is advisable. In fact, long-term maintenance with oral antivirals is probably the best approach in patients with HSK.
• While routine cataract post-operative patients usually stop their steroid when the bottle is empty, it is probably better for HSK patients to taper off. As a rule of thumb, I generally include a second bottle of steroid. After completing the first at standard dosage, patients are instructed to slowly taper off the second.
• If HSK patients preparing for surgery cannot fully taper off the steroid without inducing a flare-up, they should maintain the lowest dose possible for several months, and the surgery center should be notified.

• These cases are not ideal for surgery on the same day as their evaluation. They should be reviewed with the surgery center before the patient’s first examination.

Herpes Zoster

Herpes zoster ophthalmicus (HZO) is similar to HSV ophthalmic disease—except that:

• HZO manifestations tend to follow a specific chronology relative to the initial shingles flare-up.
• The resultant disease is often more chronic and unpredictable than with HSV.

Treatment of HZO is similar to HSK (steroid and oral antiviral). For this reason, anyone with a history of chronic (or rarely recurrent) or recent HZO should follow the same general guidelines as with IEK or HSK:

•  Aspire for a period of at least three months of quiescence from the original episode.
• Once this is achieved, use prophylactic oral antivirals, though at higher levels than with HSV-linked corneal disease (acyclovir 800mg bid or valacyclovir 1 gram qd).
• If patients preparing for surgery cannot fully taper off the steroid despite months of therapy, they should maintain the lowest dose possible for several months, and the surgery center should be made aware of the case.

Conclusion

After discussing Dr. Elms’ case, surgery was delayed for a few months. Steroid use was slowly decreased during this time, and the patient’s response was carefully observed. A successful taper was achieved, and the patient is now awaiting surgery. Before the procedure, Dr. Elms will initiate antivirals as prophylaxis. After surgery, the steroid will be slowly withdrawn.

This general guideline can be applied to most cases of herpetic eye disease. But each is unique, and resultant treatment plans should reflect that. An easy rule of thumb for all cataract patients with unusual concomitant pathology is to follow Dr. Elms’s example—communicate with the surgery facility before referring the patient. This kind of discussion and pre-planning can improve patient care and streamline their surgical experience.