Coding Strategies

Letters of Medical Necessity: Making a Case to Get Paid

coding strategies

Letters of Medical Necessity: Making a Case to Get Paid


It's been said many times that the art of writing a letter is lost. It may be as lost as the art of prescribing GP contact lenses. Lost though the art may be, writing letters of medical necessity (LMNs) is necessary if you are to get paid for many of the services that you provide.

When to Use an LMN

First, as we've discussed in previous columns, you should write an LMN every time you use the unlisted ophthalmological code, 92499. If you get paid for something under a 92499 without an LMN, it just means that the insurance company made an error.

Second, you should use an LMN any time you do something out of the ordinary — like bill an insurance company for prescribing contact lenses. No, I don't send a letter to VSP when I use its "Medically Necessary Contact Lens Benefit." However, I make it a habit to send one almost every time I bill a 9231× code. If a material benefit is available and I am billing a private carrier for materials, I definitely use one.

You will also need an LMN whenever a billed claim is rejected and the reason given states, "not medically necessary." In such cases, you may have actually done something that is not medically necessary. If you get such a letter, you need to check that the diagnosis code you used is on the limited data set of the local or national carrier determination policy for the procedure code used.

You should also have one of these documents ready to go for the unlisted procedures that you perform, such as aberrometry. However, you might also use this code and accompanying LMNs for blood flow analyzers, etc. Remember, billing for medically necessary contact lenses is just like billing for anything else. Letters are required for retinal procedures as well.

When sending an LMN, always include a copy of the letter that requests more documentation.

LMNs Made Easy

If you begin using LMNs correctly, then you will definitely be generating a lot more of them than you do now. Like most of you, I am basically lazy and don't want to be bothered by such tasks. So it's incumbent upon us to find a method that makes this menial task as quick, easy and painless as possible.

For me the answer was in my word processor. You can create form documents with drop-down boxes. By creating a form document that also has mail merge fields in it, you can go to your patient, then select the insurance company, the services, the materials and the correct diagnosis, making the letter fly.

In each of the drop down boxes, you need to put in every type of medically necessary contact lens service, material and diagnosis code that you might use or encounter. That way, you can craft one form letter to fit any situation.

I believe it's important to include a sentence telling the insurance company that you know what definition of medical necessity that insurance company uses.

Take a Look

I've posted a sample of one of my LMNs in the online version of this article at Next month, we'll talk about why you need an office brochure. CLS

Dr. Newman has been in private practice in Dallas, Texas since 1986 specializing in vision rehabilitation through contact lenses as well as corneal disease management, optometric medicine and refractive surgery.


Clarke D. Newman, O.D., F.A.A.O.
Diplomate in the Section on Cornea and Contact Lenses
of the American Academy of Optometry

Optometric Medicine and the Treatment of Eye Disease

Optometric Glaucoma Specialist

Cornea, Specialty Contact Lens, and Refractive Surgery Consultation

January 5, 2005

RE: Letter of Medical Necessity for Patient John Doe, # : 1234

To Whom It May Concern:

I have examined Mr. Doe, who has Keratoconus, Stable Condition (CPT Code 361.60), and who, according to the 1999 American Medical Association "Definition of Medical Necessity," qualifies for medically necessary contact lenses. It is, therefore, medically necessary for Mr. Doe to wear rigid gas permeable contact lenses. I write this letter for review of benefits under John's plan for the prescribing of contact lenses that are therapeutic, and not cosmetic.

The material code (HCPCS) for this diagnosis is:

V2530: Contact lens, scleral, gas permeable, per lens (Two lenses will be needed.)

The professional service code (CPT) is:

92313: Prescription of optical and physical characteristics of and fitting of contact lens, with medical supervision of adaptation; corneoscleral lens, each eye, except for aphakia. (Two procedures will be needed.)

Please contact me immediately about Mr. Doe's available benefits, or if you have any questions.


Clarke D. Newman, OD, FAAO


Copies: File
Enclosures: Topographies

Plaza Vision Center·600 North Pearl Street, Suite G-204·Dallas, Texas 75201-7472
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