Endothelial Keratoplasty

POLICY NUMBER

L.9.03.412

DESCRIPTION

Endothelial keratoplasty, also referred to as posterior lamellar keratoplasty, is a form of corneal transplantation in which the diseased inner layer of the cornea, the endothelium, is replaced with healthy donor tissue. Specific techniques include Descemet stripping endothelial keratoplasty, Descemet stripping automated endothelial keratoplasty, Descemet membrane endothelial keratoplasty, and Descemet membrane automated endothelial keratoplasty. Endothelial keratoplasty, and particularly the specific techniques mentioned, are becoming standard procedures. Femtosecond laser-assisted endothelial keratoplasty and femtosecond and excimer laser-assisted endothelial keratoplasty have also been reported as alternatives to prepare the donor endothelium.

Corneal Disease

The cornea, a clear, dome-shaped membrane that covers the front of the eye, is a key refractive element for vision. Layers of the cornea consist of the epithelium (outermost layer); Bowman layer; the stroma, which comprises approximately 90% of the cornea; Descemet membrane; and the endothelium. The endothelium removes fluid from and limits fluid into the stroma, thereby maintaining the ordered arrangement of collagen and preserving the cornea’s transparency. Diseases that affect the endothelial layer include Fuchs endothelial dystrophy, aphakic and pseudophakic bullous keratopathy (corneal edema following cataract extraction), and failure or rejection of a previous corneal transplant.

Treatment

The established surgical treatment for corneal disease is penetrating keratoplasty, which involves the creation of a large central opening through the cornea and then filling the opening with full-thickness donor cornea that is sutured in place. Visual recovery after penetrating keratoplasty may take one year or more due to slow wound healing of the avascular full-thickness incision, and the procedure frequently results in irregular astigmatism due to sutures and the full-thickness vertical corneal wound. Penetrating keratoplasty is associated with an increased risk of wound dehiscence, endophthalmitis, and total visual loss after relatively minor trauma for years after the index procedure. There is also risk of severe, sight-threatening complications such as expulsive suprachoroidal hemorrhage, in which the ocular contents are expelled during the operative procedure, as well as postoperative catastrophic wound failure.

A number of related techniques have been, or are being, developed to selectively replace the diseased endothelial layer. One of the first endothelial keratoplasty techniques was termed deep lamellar endothelial keratoplasty, which used a smaller incision than penetrating keratoplasty, allowed more rapid visual rehabilitation, and reduced postoperative irregular astigmatism and suture complications. Modified endothelial keratoplasty techniques include endothelial lamellar keratoplasty, endokeratoplasty, posterior corneal grafting, and microkeratome-assisted posterior keratoplasty. Most frequently used at this time are Descemet strippingendothelial keratoplasty, which uses hand-dissected donor tissue, and Descemet stripping automated endothelial keratoplasty, which uses an automated microkeratome to assist in donor tissue dissection.These techniques include donor stroma along with the endothelium and Descemet membrane, which results in a thickened stromal layer after transplantation. If the donor tissue comprises the Descemet membrane and endothelium alone, the technique is known as Descemet membrane endothelial keratoplasty. By eliminating the stroma on the donor tissue and possibly reducing stromal interface haze, Descemet membrane endothelial keratoplasty is considered a potential improvement over Descemet stripping endothelial keratoplasty and Descemet stripping automated endothelial keratoplasty. A variation of Descemet membrane endothelial keratoplasty is Descemet membrane automated endothelial keratoplasty. Descemet membrane automated endothelial keratoplasty contains a stromal rim of tissue at the periphery of the Descemet membrane endothelial keratoplasty graft to improve adherence and improve handling of the donor tissue. A laser may also be used for stripping in a procedure calledfemtosecond laser-assisted endothelial keratoplasty and femtosecond and excimer laser–assisted endothelial keratoplasty.

Endothelial keratoplasty involves removal of the diseased host endothelium and Descemet membrane with special instruments through a small peripheral incision. A donor tissue button is prepared from corneoscleral tissue after removing the anterior donor corneal stroma by hand (e.g., Descemet stripping endothelial keratoplasty) or with the assistance of an automated microkeratome (e.g., Descemet stripping automated endothelial keratoplasty)or laser (femtosecond laser-assisted endothelial keratoplasty or femtosecond and excimer laser-assisted endothelial keratoplasty). Donor tissue preparation may be performed by the surgeon in the operating room or by the eye bank and then transported to the operating room for final punch out of the donor tissue button. For minimal endothelial damage, the donor tissue must be carefully positioned in the anterior chamber. An air bubble is frequently used to center the donor tissue and facilitate adhesion between the stromal side of the donor lenticule and the host posterior corneal stroma. Repositioning of the donor tissue with the application of another air bubble may be required in the first week if the donor tissue dislocates. The small corneal incision is closed with one or more sutures, and steroids or immune-suppressants may be provided topically or orally to reduce the potential for graft rejection. Visual recovery following endothelial keratoplasty is typically 4 to 8 weeks.

Eye Bank Association of America statistics have shown the number of endothelial keratoplasty cases in the United States increased from 30,710 in 2015 to 35,555 in 2019. The Eye Bank Association of America estimated that, as of 2016, nearly 40% of corneal transplants performed in the United States were endothelial grafts. As with any new surgical technique, questions have been posed about long-term efficacy and the risk of complications. Endothelial keratoplasty-specific complications include graft dislocations, endothelial cell loss, and rate of failed grafts. Long-term complications include increased intraocular pressure, graft rejection, and late endothelial failure.

Endothelial keratoplasty is a surgical procedure and, as such, is not subject to regulation by the U.S. Food and Drug Administration (FDA). Several microkeratomes have been cleared for marketing by the FDA through the 510(k) process.

Indications for  Keratoprosthesis are discussed in a separate policy.

POLICY

Endothelial keratoplasty (Descemet stripping endothelial keratoplasty, Descemet stripping automated endothelial keratoplasty, Descemet membrane endothelial keratoplasty, or Descemet membrane automated endothelial keratoplasty) may be considered medically necessary for the treatment of endothelial dysfunction, including but not limited to:

Femtosecond laser-assisted endothelial keratoplasty or femtosecond and excimer laser-assisted endothelial keratoplasty are considered investigational.

Endothelial keratoplasty is considered investigational when endothelial dysfunction is not the primary cause of decreased corneal clarity.

POLICY EXCEPTIONS

Federal Employee Program (FEP) may dictate that all FDA-approved devices, drugs or biologics may not be considered investigational and thus these devices may be assessed only on the basis of their medical necessity.

POLICY GUIDELINES

The coverage guidelines outlined in the Medical Policy Manual should not be used in lieu of the Member’s specific benefit plan language.

Endothelial keratoplasty should not be used in place of penetrating keratoplasty for conditions with concurrent endothelial disease and anterior corneal disease. These situations would include concurrent anterior corneal dystrophies, anterior corneal scars from trauma or prior infection, and ectasia after previous laser vision correction surgery. Clinical input has suggested that there may be cases where anterior corneal disease should not be an exclusion, particularly if endothelial disease is the primary cause of the decrease in vision. Endothelial keratoplasty should be performed by surgeons who are adequately trained and experienced in the specific techniques and devices used.

Medically Necessary is defined as those services, treatments, procedures, equipment, drugs, devices, items or supplies furnished by a covered Provider that are required to identify or treat a Member's illness, injury or Mental Health Disorders, and which Company determines are covered under this Benefit Plan based on the criteria as follows in A through D:

A.  consistent with the symptoms or diagnosis and treatment of the Member's condition, illness, or injury; and

B.  appropriate with regard to standards of good medical practice; and

C.  not solely for the convenience of the Member, his or her Provider; and

D.  the most appropriate supply or level of care which can safely be provided to Member. When applied to the care of an Inpatient, it further means that services for the Member's medical symptoms or conditions require that the services cannot be safely provided to the Member as an Outpatient.

For the definition of medical necessity, “standards of good medical practice” means standards that are based on credible scientific evidence published in peer-reviewed medical literature generally recognized by the relevant medical community, and physician specialty society recommendations, and the views of medical practitioners practicing in relevant clinical areas and any other relevant factors. BCBSMS makes no payment for services, treatments, procedures, equipment, drugs, devices, items or supplies which are not documented to be Medically Necessary. The fact that a Physician or other Provider has prescribed, ordered, recommended, or approved a service or supply does not in itself, make it Medically Necessary.

Investigative is defined as the use of any treatment procedure, facility, equipment, drug, device, or supply not yet recognized as a generally accepted standard of good medical practice for the treatment of the condition being treated and; therefore, is not considered medically necessary. For the definition of Investigative, “generally accepted standards of medical practice” means standards that are based on credible scientific evidence published in peer-reviewed medical literature generally recognized by the relevant medical community, and physician specialty society recommendations, and the views of medical practitioners practicing in relevant clinical areas and any other relevant factors. In order for equipment, devices, drugs or supplies [i.e, technologies], to be considered not investigative, the technology must have final approval from the appropriate governmental bodies, and scientific evidence must permit conclusions concerning the effect of the technology on health outcomes, and the technology must improve the net health outcome, and the technology must be as beneficial as any established alternative and the improvement must be attainable outside the testing/investigational setting.

POLICY HISTORY

10/13/2009: Policy added.

11/19/2009: Approved by MPAC.

09/09/2010: Policy reviewed; policy statement unchanged. FEP verbiage added to the Policy Exceptions section.

09/28/2011: Policy reviewed; no changes.

09/27/2012: Policy reviewed; no changes.

03/01/2014: Added the following as medically necessary indications for endothelial keratoplasty: ruptures in Descemet’s membrane, iridocorneal endothelial (ICE) syndrome, and corneal edema attributed to endothelial failure. Policy statement added to state that femtosecond laser-assisted corneal endothelial keratoplasty (FLEK) or femtosecond and excimer lasers-assisted endothelial keratoplasty (FELEK) are considered investigational. Endothelial keratoplasty is not medically necessary when endothelial dysfunction is not the primary cause of decreased corneal clarity. Added ICD-9 codes 364.51, 371.22, and 371.33 to the Code Reference section.

10/15/2014: Policy reviewed; description updated. Policy statement unchanged. Policy guidelines updated regarding the use of endothelial keratoplasty.

08/28/2015: Medical policy revised to add ICD-10 codes.

11/02/2015: Policy description updated. Policy statements unchanged. Policy guidelines updated to add medically necessary and investigative definitions.

04/25/2016: Policy description updated. Investigational statement updated to change "Femtosecond laser-assisted corneal endothelial keratoplasty" to "Femtosecond laser-assisted endothelial keratoplasty."

05/27/2016: Policy number A.9.03.22 added.

10/24/2017: Policy description updated regarding the number of endothelial keratoplasty cases in the United States. Policy statements unchanged.

04/16/2018: Policy reviewed; no changes.

04/10/2019: Policy reviewed; no changes.

04/17/2020: Policy reviewed; no changes.

09/25/2020: Code Reference section updated to add new ICD-10 diagnosis codes H18.511, H18.512, H18.513, H18.519, T86.8401, T86.8402, T86.8403, T86.8409, T86.8411, T86.8412, T86.8413, and T86.8419, effective 10/01/2020.

06/09/2021: Policy description updated regarding the number of endothelial keratoplasty cases in the United States. Policy statements unchanged. Policy Guidelines updated to change "Nervous/Mental Conditions" to "Mental Health Disorders" and "Medically Necessary" to "medical necessity."

05/20/2022: Policy description updated. Policy statements unchanged. Code Reference section updated to remove deleted ICD-10 diagnosis codes H18.51, T86.840, and T86.841.

04/20/2023: Policy reviewed. Policy statement updated to change "not medically necessary" to "investigational."

04/24/2024: Policy reviewed; no changes.

04/22/2025: Policy reviewed; no changes.

06/15/2025: Policy number changed from "A.9.03.22" to "L.9.03.412."

SOURCE(S)

Blue Cross Blue Shield Association Policy # 9.03.22 

CODE REFERENCE

This may not be a comprehensive list of procedure codes applicable to this policy.

The code(s) listed below are ONLY medically necessary if the procedure is performed according to the "Policy" section of this document.

Covered Codes

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