Coding Q&A

Interdisciplinary surgical coding


When Two Surgeons Work Together: Interdisciplinary Surgical Coding


When surgeons from two different specialties operate during the same session, it is tricky to code correctly and optimize each surgeon's reimbursement. You must master modifiers and must foster coding communication between the two parties. Here I am writing only about Medicare reimbursement.

Common examples of two sub-specialties working together:

Anterior Segment (Cataract) and Retina. The cataract surgeon finds that, during the procedure, the nucleus drops into the posterior vitreous. The retinal surgeon is asked to join in performing the surgery. In some cases, the retinal surgeon just fragments and removes the crystalline lens and the anterior-segment surgeon places the intraocular lens. In other instances, the retinal surgeon will complete the case and insert the intraocular lens.

Anterior Segment (Cornea) and Retina. The corneal specialist removes the cornea in preparation for a corneal transplant and places a temporary keratoprosthesis. The retinal surgeon then performs the retinal procedure, followed by the corneal specialist removing the temporary keratoprosthesis and doing a penetrating keratoplasty.

Glaucoma and Retina. A retinal physician is often involved in glaucoma surgery, especially when shunt placement is involved.


The principal coding dilemma remains achieving optimal reimbursement for each surgeon. This goal is to enable each surgeon to be paid independently for each procedure according to Medicare's multiple surgery reimbursement guidelines, wherein the first procedure is paid at 100% of the allowable and next four are paid at 50% of the allowable.

Modifiers: When coding joint cases, do not use modifier 62 — the cosurgery modifier. When used, this modifier engenders payment at 125% of the allowable for all procedures performed. Then each surgeon receives 62.5% of the total allowable. Rather, each surgeon should bill separately according to multiple surgery rules and apply modifier 79 as the last modifier on each procedure code used.

► It is imperative to have mastered the uses of the modifiers — often different modifiers may be needed when coding the same surgery.
► Use modifier 78 when the procedure is related to the primary procedure that was performed in the global period. You still would append modifier 79 as the next modifier.
► Use modifier 79 on each code and when the procedure is considered “unrelated” according to Medicare.

A final word on Medicare's concept of “unrelated”: It is not the medical concept. Retinal detachment following cataract surgery is related in a physician's thinking but not in Medicare's.

Case Scenario:

Patient presented with a vitreous hemorrhage and cataract with pseudoexfoliation and loose zonules in the right eye. The vitreoretinal surgeon performs a pars plana vitrectomy and lensectomy and the anterior-segment surgeon inserts a posterior-chamber IOL. Code for two surgeons.

Vitreoretinal Surgeon:


(1) 379.23 Vitreous hemorrhage, right eye

(2) 366.23 Cataract, right eye


Procedure Code(s)

(1) 66850 Removal of lens material; Phacoemulsification technique, Modifier 79-RT

(2) 67036 Vitrectomy, pars plana approach, right eye

Modifiers 51-79-RT

Anterior-Segment Surgeon:


(1) 379.31 Aphakia


Procedure Code(s)

(1) 66985 Insertion of secondary IOL, Modifier 79-RT

Use modifier-79 for each surgeon to be paid 100% of the allowable, plus 50% of the subsequent four procedures. RP

CPT codes ©2010 American Medical Association.

Riva Lee Asbell can be contacted at, where the order form for her new book, Tips on Ophthalmic Surgical Coding by Subspecialty, can be found and downloaded under Products/Books.