No controlled clinical study has directly compared PTK with other forms of treatment, including superficial keratectomy (used to treat superficial lesions), or lamellar keratoplasty (used to treat deeper lesions), or anterior stromal puncture (used to treat recurrent corneal erosions). The FDA approval was based on data from uncontrolled trials of patients with a variety of corneal pathologies. For example, Summit Technology presented data on 398 eyes, including 103 eyes with dystrophy (25.9%), 64 eyes with recurrent erosion (16.1%), and 231 eyes with scars, opacities, or other irregular surfaces (58%). Outcomes included best-corrected visual acuity and/or decrease in irritative symptoms, such as pain and discomfort. Among cases undergoing PTK to increase comfort, 88.5% were considered successes at one year. Among those with visual impairment, 63.4% were considered successes. The most common adverse effect was corneal scarring and glare, occurring in 13.7% and 12.2% of cases, respectively. The results of this trial have also been summarized by Maloney and colleagues. Superficial mechanical keratectomy is regarded as a minimally invasive, safe, and effective procedure to remove the superficial layer of the cornea. While PTK offers a more precise and elegant method of epithelial removal, no controlled studies have demonstrated that this technological superiority results in an improved patient health benefit. The precision of PTK may be most significant when deeper corneal lesions involving Bowman's layer are present. In this situation, PTK presents a minimally invasive alternative to lamellar keratoplasty.
There are inadequate data regarding the effectiveness of PTK in treating recurrent corneal erosions and infectious keratitis.
A literature review performed for the period of 2005 through 2009 did not identify any published articles that would prompt reconsideration of the above policy. Therefore the policy statement is unchanged.
A search of peer reviewed literature through July 2011 identified no new clinical trial publications or any additional information that would change the coverage position of this medical policy.
Disclaimer for coding information on Medical Policies
Procedure and diagnosis codes on Medical Policy documents are included only as a general reference tool for each policy. They may not be all-inclusive.
The presence or absence of procedure, service, supply, device or diagnosis codes in a Medical Policy document has no relevance for determination of benefit coverage for members or reimbursement for providers. Only the written coverage position in a medical policy should be used for such determinations.
Benefit coverage determinations based on written Medical Policy coverage positions must include review of the member’s benefit contract or Summary Plan Description (SPD) for defined coverage vs. non-coverage, benefit exclusions, and benefit limitations such as dollar or duration caps.