DESCRIPTION
Intrastromal corneal ring segments consist of micro-thin soft plastic inserts of variable thickness that are placed in the periphery of the cornea. Intrastromal corneal ring segments have been investigated as a means of improving vision in diseases such as keratoconus and pellucid marginal degeneration, and for refractive surgery to correct mild myopia.
Intrastromal corneal ring segments (e.g. Intacs™) consist of 2 arc-shaped segments that are surgically inserted through a radial incision and are placed in the corneal stroma. The procedure is performed in an ambulatory setting under local anesthesia. They affect refraction in the eye by physically changing the shape of the cornea (flattening the front of the eye), thereby correcting the irregular corneal shape. If required, the implants can be removed at a later date.
In myopia, intrastromal inserts correct myopia by flattening the center of the cornea and represent an alternative to laser in situ keratomileusis (LASIK) and other refractive surgeries. The proposed advantages of the intrastromal corneal rings are that their insertion does not affect the central cornea, and thus, their effect is not related to the healing process in the cornea. No corneal tissue is removed, and the implants are reversible.
Keratoconus, a progressive bilateral dystrophy, is a non-inflammatory eye condition in which the normally round dome-shaped cornea progressively thins causing a cone-like bulge to develop. This results in significant visual impairment.
Pellucid marginal degeneration is a noninflammatory progressive degenerative disease, typically characterized by bilateral peripheral thinning (ectasia) of the inferior cornea. Deterioration of visual function results from the irregular astigmatism induced by asymmetric distortion of the cornea. Intracorneal ring segment implantation has been investigated as a treatment for pellucid marginal degeneration. Other proposed treatments include rigid, gas permeable contacts, crescentic lamellar keratoplasty, penetrating keratoplasty, and corneal wedge excision.
POLICY
Intrastromal corneal ring segments, for the treatment of keratoconus, are considered medically necessary if the medical appropriateness criteria are met. (See Medical Appropriateness below.)
Intrastromal corneal ring segments for the treatment of myopia are considered not medically necessary.
Intrastromal corneal ring segments for the treatment of other conditions / diseases, including, but not limited to all other vision correction are considered investigational.
Any device utilized for this procedure must have FDA approval specific to the indication, otherwise it will be considered investigational.
MEDICAL APPROPRIATENESS
Intrastromal corneal ring segments, for the treatment of keratoconus, is considered medically appropriate if ALL of the following criteria are met:
Individual is 21 years of age or older
Individual has experienced progressive deterioration in the vision
Best correction using contact lenses or spectacles cannot achieve 20/40 or better
Central cornea is clear
Corneal thickness of 450 microns or greater at the proposed incision site
Demonstrates an inability to perform activities of daily living (ADLs) in current visual state
Procedure intended to reduce or eliminate myopia and/or astigmatism associated with keratoconus
Procedure intended to restore functional vision
Procedure intended to defer the need for a corneal transplant procedure (the only remaining treatment option)
IMPORTANT REMINDER
We develop Medical Policies to provide guidance to Members and Providers. This Medical Policy relates only to the services or supplies described in it. The existence of a Medical Policy is not an authorization, certification, and explanation of benefits or a contract for the service (or supply) that is referenced in the Medical Policy. For a determination of the benefits that a Member is entitled to receive under his or her health plan, the Member's health plan must be reviewed. If there is a conflict between the Medical Policy and a health plan, the express terms of the health plan will govern.
ADDITIONAL INFORMATION
No controlled studies were found in the published literature that validates the application of intrastromal corneal ring segments for the treatment of other conditions / diseases of the eye. No evidence was found to demonstrate that outcomes of this procedure for conditions other than keratoconus were significantly better than currently accepted treatments.
SOURCES
American Academy of Ophthalmology. (2007, September). Refractive Errors: Surgery. Retrieved September 26, 2011 from http://one.aao.org/printerfriendly.aspx?cid=33ab37b4-ee53-4784-9c04-3ac048598a6c.
American Academy of Ophthalmology. (2007, September). Refractive Errors & Refractive Surgery Preferred Practice Patterns. Retrieved September 26, 2011 from http://one.aao.org/printerfriendly.aspx?cid=e6930284-2c41-48d5-afd2-631dec586286.
BlueCross BlueShield Association. Medical Policy Reference Manual. (9:2010). Implantation of intrastromal corneal ring segments (9.03.14). Retrieved September 26, 2011 from BlueWeb. (18 articles and/or guidelines reviewed)
BlueCross BlueShield of Tennessee network physicians. February 2004.
Coskunseven, E., Kymionis, G., Tsiklis, N., Atun, S., Arslan, E., Jankov, M., et al. (2008). One-year results of intrastromal corneal ring segment implantation (Kera Ring) using femtosecond laser in patients with keratoconus. American Journal of Ophthalmology, 145 (5), 775 - 779. (Level 2 Evidence - independent study)
Coskunseven, E., Onder, M., Kymionis, G., Diakonis, V., Arslan, E., Tsiklis, N., et al. (2007). Combined Intacs and posterior chamber toric implantable collamer lens implantation for keratoconic patients with extreme myopia. American Journal of Ophthalmology, 144 (3), 387 - 389. (Level 2 Evidence - independent study)
Kymionis, G. Siganos, C., Tsiklis, N., Anastasakis, A., Yoo, S., Pallikaris A. et al. (2006). Long-term follow-up of Intacs in keratoconus. American Journal of Ophthalmology, 143, (2), 236 - 244. (Level 2 Evidence, Independent study)
Lai, M., Tang, M., Andrade, E., Li, Y., Khurana, R., Song, J., et al. (2006). Optical coherence tomography to assess intrastromal corneal ring segment depth in keratoconic eyes. Journal of Cataract Refraction Surgery, 323 (11), 1860 - 1865. (Level 4 Evidence - Industry supported)
National Institute for Health and Clinical Excellence. (2007, July). Corneal implants for keratoconus. Retrieved September 26, 2011 from http://www.nice.org.uk/nicemedia/pdf/IPG227guidance.pdf.
Schwartz, A. P., Tinio, B. O., Babayan, A., Naikoo, H. N., Roberts, B., & Asbell, P.A. (2006). Intrastromal corneal ring implantation (360 degrees ring) for myopia: A 5-year follow-up. Eye & Contact Lens. 32 (3), 121 - 123. (Level 2 Evidence - Independent study)
Schwartz. A.R., Tinio, B.O., Esmail, F., Babayan, A., Naikoo, H.N., & Asbell, P.A. (2006). Ten-year follow-up of 360 degrees intrastromal corneal rings for myopia. Journal of Refractive Surgery. 22 (9), 878 - 883. (Level 2 Evidence - Independent study)
Sharma, M., & Box Wachler, B. S. (2006). Comparison of single-segment and double-segment intacs for keratoconus and post-lasik ectasia. American Journal of Ophthalmology, 141 (5), 891 - 895. (Level 2 Evidence - Industry supported)
Shetty, R., Narayana, K., Mathew, K., Anand, D., Mhaska, P., & Shetty B. (2009). Safety and efficacy of Intacs in Indian eyes with keratoconus: an initial report. Indian Journal of Ophthalmology, 57 (2), 115 - 119. (Level 2 Evidence - Independent study)
U.S. Food and Drug Administration. (2004, March). Center for Devices and Radiological Health. Summary of Safety and probable benefits H040002. Retrieved September 26, 2011 from http://www.accessdata.fda.gov/cdrh_docs/pdf4/H040002b.pdf.
ORIGINAL EFFECTIVE DATE: 3/1/2003
MOST RECENT REVIEW DATE: 11/10/2011
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Policies included in the Medical Policy Manual are not intended to certify coverage availability. They are medical determinations about a particular technology, service, drug, etc. While a policy or technology may be medically necessary, it could be excluded in a member's benefit plan. Please check with the appropriate claims department to determine if the service in question is a covered service under a particular benefit plan. Use of the Medical Policy Manual is not intended to replace independent medical judgment for treatment of individuals. The content on this Web site is not intended to be a substitute for professional medical advice in any way. Always seek the advice of your physician or other qualified health care provider if you have questions regarding a medical condition or treatment.
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