Utilizing Osmolarity Testing in Practice

Mitchell Jackson, MD:

Hi, I am Dr. Mitchell Jackson, the founder and CEO of Jacksoneye, 31 years in private practice in Lake Villa, Illinois, just outside of Chicago.

Question:

Why do you include osmolarity testing in your office protocol for dry eye or surgical patients?

Mitchell Jackson, MD:

I’ve been using osmolarity testing from the beginning, from the first generation to the current generation ScoutPro device, which has made it a lot easier for my technicians. But despite that, osmolarity is an objective test, and objective tests have a lot more clout than subjective tests because it’s something that has meaning to a patient. It’s easy for a patient to understand. For example, a diabetic knows their A1C number, and if their A1C number’s out of control, then they know they’re in trouble if they’re not really compliant with their diabetes.

This osmolarity is another way to assess the status of the tear film, homeostasis, for example, which is part of all the DEWS and TFOS definitions in dry eye published. So homeostasis of tear film is critical, and so we have an objective measure if it’s high in one eye or if the difference between the two eyes is greater than eight, for example, then they have a tear film that’s not homeostatic and they have a problem. Then I can share that with the patient and explain to them it’s their dry eye. I do a lot of cataract surgery or refractive surgery and tell them it’s pre-existent, first of all. You have ocular surface disease because if you don’t do testing that’s objective to show they have it, they think you caused it when you touched their eye doing surgery. So it’s important for us to show they have a problem.

Secondly, it’s important that you test the problem so you get better keratometry readings, so you get better IOL calculation readings, so you don’t have a miscalculation in an IOL power. Many authors out there publish stuff, such as Bill Trattler, showing you could have keratometric reading off from dry eye and you can be up to a diopter and a half off in an IOL power, especially in a patient doing a premium IOL, which would be a nightmare because now you have to enhance them and they’re unhappy. So that’s one of the reasons why I do osmolarity testing. It’s the objective test. Whether it’s perioperative or just an ocular surface disease patient in the clinic, it’s a way to… And also, it helps enhance compliance.

So let’s say you have a patient, you start treatment and the number’s like 340. It’s a really high level. I kind of explain to them that’s a state of dehydration of their tear film, so they understand that. A high number means it’s really dehydrated and then the number starts to come down as you treat them and it’s goes from 340 to 310. It’s getting better, as they see my treatment’s working because subjectively signs and symptoms never correlate. At least you have a sign objectively tested showing improvement. It might keep them enhanced to continue the treatment with compliance and I always eventually tell them the symptoms will go away if the signs improve.

Question:

Why does osmolarity testing come first for patient evaluations?

Mitchell Jackson, MD:

So I mean, the way we utilize osmolarity testing, it’s part of our preoperative workup, whether it’s a refractive surgery or cataract surgery evaluation or just a regular dry eye ocular surface disease evaluation. Everybody gets osmolar testing at their first visit to see where they’re at. If it’s normal, there’s no ocular surface disease, we don’t necessarily have to test it again. If it’s abnormal, we’re obviously going to start some type of therapy and then we’re going to use it to reassess objectively if they’re improving on their followup visit. I typically innate nonsurgical patient like just an ocular surface disease patient. We’ll use osmolarity testing and see them about six weeks later.

I want them to be committed to six weeks of therapy and I almost can guarantee there’s going to be an improvement. If it’s a perioperative patient, I have to be really aggressive with their treatment to get them ready for surgery within two weeks, so we’ll be really aggressive with our therapy and we’ll probably test it at two weeks right before surgery to make sure at least it’s improving. If I feel the readings are accurate enough to go ahead with surgery, we will and we’ll just continue to do therapy or we’ll just delay surgery if I feel it’s not good enough yet.

Question:

What types of patients do you recommend osmolarity testing for?

Mitchell Jackson, MD:

Because we know ocular surface disease or dry eye is really a mixed mechanism of aqueous and meibomian issues and so everybody has a misnomer and think we should only use osmolarity patients in the minority of aqueous deficient patients. But no, if there’s a loss of tear film homeostasis, they have either meibomian gland disease or aqueous deficient disease and so it’s going to show and be another objective sign. In conjunction with other things, you want to do dynamic meibomian imaging to look at the glands. You might want to do InflammaDry to look at MMP-9 levels. You obviously want to stay in the cornea measure tear breakup time. There’s a lot of things in the ocular surface evaluation you can do, but again, this is objective testing, which I really like and I’ll use it in all these patients. It’s not to be just used in aqueous deficient only meibomian disease only. I use it pretty much anybody who has any ocular surface issues.