Article

Coding for Minimally Invasive Glaucoma Surgery

Rapidly evolving landscape for MIGS

To examine long-term trends within glaucoma surgery, the Corcoran Consulting Group has tracked paid claims for Medicare Part B since 1994. Figure 1 graphically displays data through 2015 for the major categories of glaucoma surgery: laser surgeries, trabeculectomies, tubes, minimally invasive glaucoma surgeries (MIGS), and all others.

FIGURE 1. PART B MEDICARE GLAUCOMA SURGERY

MIGS WITH GDD

We observe that MIGS is a rapidly growing category, while the other categories are flat or declining. The largest contributor to this growth is 0191T (insertion of anterior segment aqueous drainage device, without extraocular reservoir, internal approach, into the trabecular meshwork; initial insertion). At present, the only FDA-approved product that fits this description is the iStent (Glaukos).

Table 1 summarizes the MIGS procedures that rely on a glaucoma drainage device (GDD). The applicable permanent Category I codes and the temporary, emerging technology Category III codes (i.e., those ending in “T”) are listed in Table 2.

TABLE 1. GLAUCOMA DRAINAGE DEVICES IN MIGS
BRAND NAME MANUFACTURER MECHANISM OF ACTION CPT CODE FDA COMMENTS
CyPass Micro-Stent Alcon (Formerly Transcend Medical) Shunts aqueous from the anterior chamber to the supraciliary and/or suprachoroidal space. 0474T (effective 7/1/17) PMA (2016) Ab interno, in conjunction with cataract extraction
ExPRESS Mini Glaucoma Shunt Alcon (Formerly Optonol) Shunts aqueous from the anterior chamber to a filtering conjunctival bleb. 66183 510(k) (2003) Ab externo, with or without cataract extraction
Hydrus Microstent Ivantis Implanted in Schlemm’s canal to facilitate aqueous outflow by stretching the wall and scaffolding the canal, allowing for more flow within the aqueous outflow system. TBD No Ab interno, in conjunction with cataract extraction
InnFocus Microshunt Santen (Formerly InnFocus) Shunts fluid from anterior chamber to subconjunctival space under a subconjunctival sub-Tenon’s flap. 66183 No Ab externo with mitomycin C, with or without cataract surgery
iStent Glaukos Stent creates bypass of aqueous through the trabecular meshwork from the anterior chamber into Schlemm’s canal. 0191T PMA (2012) Ab interno, in conjunction with cataract extraction
iStent Supra Micro-Bypass Stent Glaukos Shunts aqueous into the suprachoroidal space. 0253T No Ab interno, with or without cataract surgery
iStent Inject Glaukos Two 2nd generation iStents are implanted sequentially in adjacent areas of trabecular meshwork using an injector. 0191T
+0376T
No Ab interno, with or without cataract surgery
SOLX Gold Shunt SOLX Shunts aqueous from the anterior chamber to the suprachoroidal space. 66183 No Ab externo, with or without cataract extraction
XEN Gel Stent Allergan (Formerly Aquesys) Shunts aqueous from the anterior chamber to subconjunctival space, creating a filtering bleb that becomes, over time, a low-lying drainage area. 0449T
+0450T
510(k) (2016) Ab interno, with or without cataract surgery
All CPT codes © 2017, American Medical Association
TABLE 2. APPLICABLE CPT CODES FOR MIGS WITH GDD
CPT DESCRIPTION COMMENT
66183 Insertion of anterior segment aqueous drainage device, without extraocular reservoir, external approach Key words: “external approach.” An ab externo surgical approach is used by ExPRESS, InnFocus, and SOLX
0191T Insertion of anterior segment aqueous drainage device, without extraocular reservoir, internal approach, into the trabecular meshwork; initial insertion Key words: “internal approach.” An ab interno surgical approach into TM is used by iStent
+0376T Each additional device insertion (List separately in addition to code for primary procedure) (Use 0376T in conjunction with 0191T) Key words: “additional device.” This add-on code is only used when a second device is implanted at the same time as the initial device
0253T Insertion of anterior segment aqueous drainage device, without extraocular reservoir, internal approach, into the suprachoroidal space Key words: “suprachoroidal space.” An ab interno surgical approach aims to implant the iStent Supra or the CyPass into the suprachoroidal space. (see discussion above)
0449T Insertion of aqueous drainage device, without extraocular reservoir, internal approach, into the subconjunctival space; initial device Key words: “subconjunctival space.” An ab interno approach used by XEN Gel stent.
+0450T Each additional device insertion (List separately in addition to code for primary procedure) (Use 0450T in conjunction with 0449T) Key words: “additional device.” This add-on code is only used when a second device is implanted at the same time as the initial device

In January 2017, the AMA CPT Panel announced a new Category III CPT code: 0474T (insertion of anterior segment aqueous drainage device, with creation of intraocular reservoir, internal approach, into supraciliary space). This code is effective July 1, 2017, and cannot be used until then. Because various descriptions of the procedure by experienced surgeons also mention insertion of the GDD into the “suprachoroidal space,” it is tempting to recommend 0253T until the new CPT code is released. In an abundance of caution, Alcon’s reimbursement team has sometimes suggested 66999 (unlisted procedure, anterior segment of eye) as an interim CPT code. For many ophthalmic surgeons, the uncertainty surrounding coding has engendered a wait-and-see approach.

TABLE 3. MIGS WITHOUT GDD
BRAND NAME MANUFACTURER MECHANISM OF ACTION CPT CODE FDA COMMENTS
Kahook Dual Blade New World Medical Goniotomy creates a pathway for aqueous to flow from the anterior chamber into Schlemm’s canal. 65820 Class 1 Device Ab interno, with or without cataract surgery
Trab 360 Sight Sciences Goniotomy creates a pathway for aqueous to flow from the anterior chamber into Schlemm’s canal. 65820 Class 1 Device Ab interno, with or without cataract surgery
Trabectome NeoMedix, Inc. Ab interno trabeculectomy creates a pathway for aqueous to flow from the anterior chamber into Schlemm’s canal. Variable 510(k) (2006) Ab interno, with or without cataract surgery
Visco 360 Sight Sciences Viscodilation of Schlemm’s canal to enhance aqueous egress. 66174 510(k) (2014) Ab interno, with or without cataract surgery

OTHER MIGS PROCEDURES

MIGS procedures that do not rely on a glaucoma drainage device include canaloplasty (with or without stent), goniotomy, and ab interno trabeculectomy. Significantly, these MIGS procedures can be performed as a solitary procedure without concurrent cataract surgery.

Coding for “ab interno trabeculectomy” is challenging because of the nomenclature in CPT and misunderstanding of the surgical technique by billers. Trabeculotomy ab externo is reported with 65850; trabeculectomy ab externo in absence of previous surgery is reported with 66170. Both codes describe glaucoma surgery using an external approach — not ab interno. Goniotomy is reported with 65820 and describes an incisional glaucoma surgery using an internal approach. A purist might opine that all of these CPT codes are inaccurate, and suggest code 66999, unlisted procedure, anterior segment of eye. In my view, “ab interno trabeculectomy” is closest to goniotomy for coding purposes.

REIMBURSEMENT

The reader may assume that assignment of a CPT code is tantamount to a doorway to reimbursement; however, it’s not quite that simple.

According to the CMS MLN Matters October 2016 update, “The fact that a drug, device, procedure, or service is assigned a HCPCS code and a payment rate under the ASC payment system does not imply coverage by the Medicare program, but indicates only how the product, procedure, or service may be paid if covered by the program. Your MAC determines whether a drug, device, procedure, or other service meets all program requirements for coverage; for example, that it is reasonable and necessary to treat the beneficiary’s condition and whether it is excluded from payment.”1

Furthermore, many payers, including Medicare, treat new GDDs and MIGS procedures as “experimental and investigational,” which typically precludes reimbursement for the surgeon and the facility. Clinical trials of GDDs also fall outside of the normal reimbursement process. CMS has established special rules on this issue that are beyond the scope of this article.2 Finally, off-label use of GDDs frequently does not fall within the coverage limitations of Medicare local coverage determination policies and might not be reimbursed. GP

References

  1. Noridian Healthcare Solutions. ASC Payment System - October 2016 Update. Available at: https://med.noridianmedicare.com/web/jeb/article-detail/-/view/10542/asc-payment-system-october-2016-update . Last accessed Feb. 3, 2017.
  2. Centers for Medicare and Medicaid Services. Medicare Benefit Policy Manual, Chapter 14 - Medical Devices. Available at: https://www.cms.gov/Regulations-and-Guidance/Guidance/Manuals/downloads/bp102C14.pdf . Last accessed Feb. 3, 2017.