Enter the whales, part 2
The ASCRS has introduced a preoperative ocular surface disease algorithm.
In my fanciful sea of dry eye care, the story line begins with Poseidon — Dr. Michael Lemp — and is carried forward by powerful sharks — Donnenfeld, Holland and McDonald. Large schools of like-minded doctors such as TFOS pick up the narrative and carry it forward through the creation of comprehensive reviews of the field, and both diagnostic and treatment paradigms arising thereof. For what it is worth, I find the CEDARS/ASPENS paper from Mark Milner and company the best source of information for advanced dry eye disease practitioners by far.
Later to arrive in this part of the ocean, the great blue whale, our largest professional organization, the American Academy of Ophthalmology, gave us an updated Preferred Practice Pattern, which is an excellent primer on all things DED; it is terrifically more current and therefore more useful than the original PPP that it replaced. A tip of the hat to Francis Mah and colleagues for this.
For those of you keeping score at home, that leaves only the American Society of Cataract and Refractive Surgery without a place in our story. At this year’s annual meeting, and in the May issue of the Journal of Cataract and Refractive Surgery, the ASCRS Cornea Clinical Committee headed by Chris Starr fills in the gap by publishing the ASCRS preoperative OSD algorithm and SPEED 2 questionnaire.
Enter the orca!
What sets the ASCRS algorithm apart is its laser-sharp focus on a single aspect of the DED universe: diagnosing and then treating DED so that surgery can be performed with minimal effect from DED. ASCRS makes no bones about either the audience it is seeking or the goal it wishes to achieve. While not perfect (see below), this singular focus makes the preoperative algorithm the single most useful document of its kind yet to be published in the field.
ASCRS is an organization founded primarily by cataract and LASIK surgeons, and it has managed to remember its roots. Through my reading of the JCRS article and discussions with Dr. Starr, it is quite clear that the working group (admit it: you want me to call it the “Starr Chamber”) was thinking about the problem of identifying DED in the context of a busy surgical practice. With efficiency in mind, it is easy to see how well-trained technicians would be able to perform the first half of the diagnostic process, including an initial examination.
Similar to the evaluation process I outlined in my three-part series on building a DED practice, a patient is screened with a survey, in this case a modified SPEED test. Point-of-care testing is then carried out; both tear osmolarity and MMP-9 testing are advised. Patients likely to have DED are then moved to more advanced tests (meibography, topography, etc) in those practices that have them. All patients then proceed to a simple, straightforward, standardized exam that can be done by either a tech or an MD/OD.
There are two specific parts of the algorithm that Dr. Starr and colleagues would like to see widely adopted. The first is the simplified exam: Look. Lift. Pull. Push. Stain. Using the slit lamp, look at the lids, lashes, the interpalpebral cornea and the quality of blinks. Lift the lid and specifically look at the superior cornea and conjunctiva. Pull on the lids to assess tone, ie, laxity. Push on the lid margins and critically evaluate the quality of meibomian gland secretion. Finally, using some sort of vital dye, look for staining and determine the tear breakup time.
At this point, any combination of signs or symptoms rules in DED, or as the Starr Chamber (there, I did it!) prefers, ocular surface disease (OSD). If OSD is ruled out, you proceed to your usual battery of preop tests and measurements and schedule surgery. In the presence of OSD, the decision tree branches here, dividing depending on the presence or absence of patient symptoms. This is where we are introduced to the other newish term ASCRS would like us to adopt: visually significant OSD, or VS-OSD. From this point forward, it is the presence of VS-OSD that determines our course of action.
With or without symptoms, if testing shows that the OSD is not visually significant, you proceed to surgical testing as usual. For example, a patient may have fluctuating vision with a rapid tear breakup time, but their ocular surface is free of staining. Topography and keratometry are normal and repeatable. Off to the OR you go. On the other hand, even in the absence of any patient symptoms, if you have significant corneal staining, dramatically abnormal point-of-care test results or obvious abnormalities on topography, surgery is delayed until VS-OSD is successfully converted to non-VS-OSD.
This aspect of the algorithm, the normalization of the need to stop the preoperative process in order to treat VS-OSD, is the most important contribution of the entire project.
Is this the perfect DED algorithm? Of course not. The authors are clear that they are addressing DED in the context of the patient who is being examined for planned anterior segment procedures such as cataract surgery and LASIK. Without the pressure to schedule surgery, there is obviously much more time available to diagnose the particular variety of DED, tailoring and adjusting a targeted treatment program. In the JCRS article, Starr and colleagues acknowledge this and suggest a more aggressive approach to treatment. This echoes my two-word approach in this setting: Ster. Roids. The use of topical steroids to rapidly convert VS-OSD to the non-visually significant variety is encouraged.
I have two quibbles and one serious criticism. Quibble No. 1 has to do with the language and wording of some of the questions on the SPEED 2 questionnaire. Less is more, especially when communicating with preop patients of all educational levels. At least one-third of the questions can be eliminated. Doing so will reduce confusion for both patients and staff (eg, I would axe every question associated with a diagnosis like allergy or blepharitis). In a similar vein, research has shown time and again that people under pressure respond to simpler language. “How badly do your eyes feel?” is easily understood by everyone.
Quibble No. 2 also leads into my only real criticism. Why use the term “neurotrophic” cornea when what you really mean is a patient with signs but no symptoms? We see this all the time in the clinic, and it is hardly the stuff of post-herpetic or de-enervation neurotrophic cornea. Just call it “asymptomatic” OSD. On the other side of the decision tree, when you are presented with a pristine cornea and what we would consider classic DED symptoms (burning, tearing), I find the term “early situational” to be perfectly adequate, although “mild symptomatic” would be simpler. However, if you uncover someone who has true neuropathic or neurogenic pain, it does not matter whether it is VS or non-VS.
Do. Not. Proceed. To. Surgery.
True neuropathic DED/OSD pain is an absolute contraindication to LASIK. It is certainly the case that an individual could have a visually significant cataract that is interfering with their normal activities and should be removed. Cataract surgery can certainly cause an increase in both OSD and sign-free symptoms. These patients need a pathway all their own.
The orcas have arrived, bringing with them a singular focus on the preoperative evaluation of OSD. In so doing, Chris Starr and his colleagues have produced the most useful algorithm yet available. Anterior segment surgeons would be well-advised to adopt this as their standard preop protocol. Indeed, it could very well be utilized in your clinic as the diagnostic foundation for a DED service. All that is missing is a companion algorithm for treating both VS-OSD and non-VS-OSD.
Look here for a multipart series outlining just such an algorithm from SkyVision, coming this fall.
- Starr CE, et al. J Cataract Refract Surg. 2019;doi:10.1016/j.jcrs.2019.03.023.
- For more information:
- Darrell E. White, MD, can be reached at SkyVision Centers, 2237 Crocker Road, Suite 100, Westlake, OH 44145; email: firstname.lastname@example.org.
Disclosure: White reports he is a consultant to Allergan, Shire, Sun, Kala, Ocular Science, Rendia, TearLab, Eyevance and Omeros; is a speaker for Shire, Allergan, Omeros and Sun; and has an ownership interest in Ocular Science and Eyevance.