**Abstract:**  
A cataract is an opacity or cloudiness in the lens of the eye(s), blocking the
passage of light through the lens, sometimes resulting in impaired vision.
Cataract development occurs in 60% of adults 65 years of age or greater. There
are multiple factors associated with cataract development. Some causes of
cataracts may include: ultraviolet- radiation exposure, complications of
diabetes, drug and/or alcohol use, smoking, and the natural process of aging.
Medicare coverage for cataract extraction and cataract extraction with
intraocular lens implant is based on services that are reasonable and
medically necessary for the treatment of beneficiaries with cataract(s). This
local coverage determination (LCD)defines coverage and describes criteria
necessary to justify the performance of cataract extraction(s) or other select
lensectomies.  
  
 **Indications and Limitations:**  
Lens extraction is considered medically necessary and therefore covered by
Medicare when one (or more) of the following conditions or circumstances
exists:

  * Cataract causing symptomatic (i.e., causing the patient to seek medical attention) impairment of visual function not correctable with a tolerable change in glasses or contact lenses resulting in specific activity limitations and/or participation restrictions including, but not limited to reading, viewing television, driving, or meeting vocational or recreational needs. Surgery is not deemed to be medically necessary purely on the basis of lens opacity in the absence of symptoms. Also other eye disease(s) including, but not limited to macular degeneration or diabetic retinopathy, have been ruled out as the primary cause of decreased visual function.  
  

  * Concomitant intraocular disease (e.g., diabetic retinopathy or intraocular tumor) requiring monitoring or treatment that is prevented by the presence of cataract.  
  

  * Cataract interfering with the performance of vitreoretinal surgery (e.g., performance of surgery for far peripheral vitreoretinal dissection and excision of the vitreous base, as in cases of proliferative vitreoretinopathy, complicated retinal detachments, and severe proliferative diabetic retinopathy).  
  

  * Lens-induced disease threatening vision or ocular health (including, but not limited to, phacomorphic or phacolytic glaucoma)  
  

  * High probability of accelerating cataract development as a result of a concomitant or subsequent procedure (e.g., pars plana vitrectomy, iridocyclectomy, procedure for ocular trauma) and treatments such as external beam irradiation  
  

  * Intolerable anisometropia or aniseikonia uncorrectable with glasses or contact lenses that exists as a result of lens extraction in the first eye (despite satisfactorily corrected monocular visual acuity).

  
  
**Visual Acuity**  
The Snellen visual acuity chart is an excellent way of measuring distance
refractive error (e.g. myopia, hyperopia, astigmatism) in healthy eyes, and is
in wide clinical use. However, testing only with high contrast letters viewed
in dark room conditions will underestimate the functional impairments caused
by some cataracts in common real life situations such as day or nighttime
glare conditions, poor contrast environments or reading, halos and starbursts
at night, and impaired optical quality causing monocular diplopia and
ghosting.  
  
While a single arbitrary objective measure might be desirable a specific
Snellen visual acuity alone can neither rule in, nor rule out the need for
surgery. It should be recorded and considered in the context of the patient's
visual impairment and other ocular findings.  
  
 **Bilateral Eye Surgery**  
If the decision to perform cataract extraction in both eyes is made prior to
the first cataract extraction, the documentation must support the medical
necessity for each procedure to be performed. Prior to admitting to surgery on
the second eye, the AAO Preferred Practice Pattern recommends that the patient
and ophthalmologist should discuss the benefit, risk and timing of second-eye
surgery when they have had the opportunity to evaluate the results of surgery
on the first eye.  
  
Immediate, sequential, bilateral surgery has advantages and disadvantages that
must be carefully weighed and discussed by the surgeon and patient. Foremost
is the risk of potentially blinding complications in both eyes. For this
reason the second eye should be treated like the eye of a different patient
using separate povidone iodine prepping, draping, instrumentation, and
supplies such as irrigating solutions, OVD, and medications. According to the
AAO Preferred Practice Pattern, "reported indications for immediate sequential
bilateral cataract surgery include the need for general anesthesia in the
presence of bilateral visually significant cataracts, rare occasions where
travel for surgery and follow-up care is a significant hardship for the
patient, and when the health of the patient may limit surgery to one surgical
encounter."  
  
**Complex Cataract Surgery  **  
Complex cataract surgery differentiates the extraordinary work performed
during the intraoperative or postoperative periods in a subset of cataract
operations including, and not limited to, the following:

    * A miotic pupil which will not dilate sufficiently to allow adequate visualization of the lens in the posterior chamber of the eye and which requires the insertion of four (4) iris retractors through four (4) additional incisions, use of an iris dilator device, a sector iridectomy with subsequent suture repair of iris sphincter, synechiolysis utilizing pupillary stretch maneuvers or sphincterotomies created with scissors.



    * The presence of a disease state that produces lens support structures that are abnormally weak or absent. This requires the need to support the lens implant with permanent intraocular sutures and/or a capsular support ring (approved by the FDA) may be necessary to allow placement of an intraocular lens.



    * Pediatric cataract surgery may be more difficult intraoperatively because of an anterior capsule which is more difficult to tear, cortex which is more difficult to remove, and the need for a primary posterior capsulotomy or capsulorhexis. Furthermore, there is additional postoperative work associated with pediatric cataract surgery.



  * Extraordinary work may occur during the postoperative period. This is the case with pediatric cases mentioned above and very rarely when there is extreme postoperative inflammation and pain.