Dry eye: Cataract and Glaucoma Segment

Dry Eye and Glaucoma Segment:
As a dry eye specialist who also sees glaucoma patients, my general recommended protocol is:

- Evaluate each glaucoma patient for candidacy for SLT (Selective Laser Trabeculoplasty) treatment. SLT “rejuvenates” the drainage area inside the eye, which allows the pressure to regulate naturally. It can be used as first-line treatment in appropriate patients - especially with dry eye, as it generally reduces pressure as well as any single eye drop can.

- Follow the rule “less is more”. This applies to the number of medications and to the frequency of application. This means to aim for “lowering the pressure enough” without overkill. It also applies to the total amount of preservatives applied to eyes. Glaucoma drops usually have the same preserving chemicals as Artificial Tears (to inhibit germs from living in the reusable bottle) and can be just as toxic. These chemicals can be hard on the tear glands and on the surface of the eyes. Unfortunately, just as the preservative free (PF) tears cost more, so too are most PF glaucoma meds.

- Patients who start with dry eye generally get worse adding glaucoma meds and will have a harder time tolerating the drops needed to prevent blindness. I recommend aggressively treating the dry eye first, or at least upon starting glaucoma care (so eyes can better tolerate these necessary chemicals). For those with advancedWhenever possible, attempt to work in concert with both glaucoma and dry eye specialists.

Dry eye and Cataract Segment:

Dry eye after Cataract: As a dry eye doctor – and one who did 30 years of cataract surgery before turning over to full time dry eye and lid surgeries, I have seen a lot of patients who appeared to suddenly get their dry eye disease immediately - or soon after - their cataract surgery. In my experience, this most often relates to multiple reasons (where some or all the following would be true):-

- Dry eye disease is a chronic, progressive problem that tends to change so slowly for most, that from day to day, there is so little change that it is almost imperceptible to the person with it. I use the analogy of the single straw placed daily on a camel’s back. From one day to the next, the camel doesn’t experience any difference – until one day, that “final straw” breaks the camel’s back. From the camel’s perspective, it was only the final straw that did it.-

- The surface of the eye is a sheet of living cells, each dependent on tears for their support and for healing. Every living cell in the human body requires support, but cells outside of the eye will get their support from blood. Eyes can’t have blood on them as we couldn’t see through blood, so we have tears instead. When an arm or leg is operated on, poor blood can mean poor healing and a complicated, less optimal outcome.-

- Cataract surgery is, by definition, surgery. Anytime we operate on an eye, that eye must heal. If the tears are not the best, then like the arm or leg, poor tears can also mean poor healing and a complicated, less optimal outcome.-

- To heal the inside of the eye, we commonly rely on use of multiple eye drops. Each drop is some chemical (or chemicals) that is/are designed to help that internal healing, but between the nature of those chemicals and the preservatives common to keeping those chemicals from germ contamination, the frequent exchange of the tears by those chemicals can leave the surface raw and irritated.-

- Irritation causes our immune system to react and bring on inflammation. Inflammation works against the tiny tear glands that are trying to make our tears – so during the healing from cataract surgery, we frequently promote more dryness in the effort to promote the internal healing required from that surgery.-

- While most eye’s tear glands will recover back to their baseline after cataract surgery (once the use of the post-operative eye drops are stopped and the eye is otherwise healed), for some, this can act as “the final straw” and break the camel’s back – causing a more substantial vicious cycle of inflammation and dryness that can be hard to recover from.-

- Also, returning to baseline may still be suboptimal and once an eye realizes it is unhappy from dryness, then (returning to my analogy) taking a little straw off the back can still leave a lot of straw on that back – and now the eye (or camel) realizes there was a problem that it didn’t perceive before.

Dry eye before Cataract Surgery - having a poor tear going into cataract surgery can cause poor readings of the corneal curvature that can translate into using the wrong power or style of implant and you have some eyes that end up with – at best - a greater need for post-operative glasses than would otherwise be required – or at worst – a style of implant that a dry eye can’t cope with and causes poor visual outcomes until the implant is exchanged or the dry eye is corrected adequately (if it can be).For all these reasons, I find it important to determine the level of dry eye and to correct it as best as possible prior to evaluating for cataract surgery.

Controlling Dry Eye Disease throughout the postoperative period (and beyond) is equally important.There are some patients whose poor vision is less the effect of the cataract and more related to the irregular corneal surface – who go through the cataract surgery only to discover that their vision is no better until the dry eye is corrected. This implies that the cataract operation may not have been wholly necessary and that simply correcting the dry eye would have taken care of their visual problems (until the cataract more fully progressed – sometimes years later).

Ideally, every cataract surgeon will also be a great dry eye doctor, but as some prefer to stay focused on the surgery, then it is incumbent on those surgeons to rely on other dry eye specialists to help get their patients to be best cared for. Team efforts often yield the best outcomes, which is why I (and many of my dry eye doctor colleagues) commonly work closely with other doctors and eye surgeons in taking care of our eye patients.

Hope this helps!