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MP 9.03.17 (Archived) Transciliary Fistulization for the Treatment of Glaucoma

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Our medical policies are designed for informational purposes only and are not an authorization, or an explanation of benefits, or a contract.  Receipt of benefits is subject to satisfaction of all terms and conditions of the coverage.  Medical technology is constantly changing, and we reserve the right to review and update our policies periodically.


Transciliary fistulization, also known as transciliary filtration or Singh filtration, uses a thermocauterization device called the Fugo blade to create a pore in the posterior chamber of the eye from the sclera through the ciliary body. This procedure reduces intraocular pressure (IOP) in patients with glaucoma by allowing aqueous fluid to seep into the subconjunctival lymphatic system.

Glaucoma is a disease characterized by degeneration of the optic disc. Elevated intraocular pressure (IOP) has long been thought to be the primary etiology, but the relationship between IOP and optic nerve damage varies among patients, suggesting a multifactorial origin. For example, some patients with clearly elevated IOP will show no damage to the optic nerve, while other patients with marginal or no pressure elevation will, nonetheless, show optic nerve damage. The association between glaucoma and other vascular disorders, such as diabetes or hypertension, suggests vascular factors may play a role in glaucoma. Specifically, it has been hypothesized that reductions in blood flow to the optic nerve may contribute to the visual field defects associated with glaucoma.

For primary-open angle glaucoma (POAG) associated with IOP, a decrease in aqueous outflow through the trabecular meshwork is believed to cause the IOP. However, there are many theories on what causes the decrease in aqueous outflow such as foreign body obstruction, trabecular endothelial cell loss, reduced trabecular pore density, disturbances in neurofeedback mechanisms, or normal phagocytic activity.

IOPs above 21 mm Hg have been shown to increase rates of visual field loss, and conventional management of the patient principally involves drug therapy to control elevated intraocular pressures to prevent or delay glaucomatous loss of vision. For POAG, drug therapy may include alpha-agonist, beta-blockers, carbonic-anhydrase inhibitors, miotic agents, and prostaglandin analogs. When the maximum tolerated medical therapy fails to control optic neuropathy, surgical care is considered the next treatment option. Surgical procedures include laser trabeculoplasty, incisional or filtering surgery, such as trabeculectomy or drainage implants, and as a last resort, ablation of the ciliary body.

Transciliary fistulization for the treatment of glaucoma, also known as transciliary filtration or Singh filtration, is a recent approach to filtering surgery. This procedure uses a thermocauterization device called the Fugo Blade to create a plasma-ablated pore or filter track from the sclera through the ciliary body to allow aqueous fluid to ooze into the subconjunctival lymphatics from the posterior chamber (behind the iris) of the eye. Plasma ablation with the Fugo Blade allows the highly vascular ciliary body to be penetrated with little or no bleeding.

Transciliary fistulization allows aqueous fluid to drain from the posterior chamber of the eye and differs from conventional filtering surgeries, such as trabeculoplasty, trabeculectomy, and drainage implant surgery, in which aqueous fluid is filtered from the anterior chamber of the eye. In the trabeculoplasty procedure, a laser is used to burn small areas of the trabecular meshwork, where normal drainage of the eye occurs, to increase aqueous fluid outflow; thereby lowering IOP. In trabeculectomy (or glaucoma filtration procedure), a portion of trabecular meshwork is surgically removed through a superficial flap of sclera to lower IOP by creating an alternate pathway for the aqueous fluid to flow from the anterior chamber to a bleb created in the subconjunctival space. If trabeculectomy has failed to reduce IOP sufficiently or a patient is considered to be at high risk for trabeculectomy failure, drainage implant surgery may be considered in which a tube is placed in the anterior chamber to shunt aqueous fluid to the subconjunctival space and lower IOP. Both trabeculectomy and drainage implant surgery often result in flat or collapsed anterior chambers and usually require that an iridectomy (placement of a hole in the iris) also be performed. Transciliary fistulization rarely requires an iridectomy and is thought to reduce tissue damage and risk of scarring and other complications associated with trabeculectomy and drainage implant surgery.

Regulatory Status

The Fugo Blade (Medisurg, Ltd.) for glaucoma was given U.S. Food and Drug Administration (FDA) 510(k) marketing clearance in October 2004 for sclerostomy for the treatment of primary open-angle glaucoma where maximum tolerated medical therapy and trabeculoplasty have failed.


Transciliary fistulization for the treatment of glaucoma is considered investigational.

Policy Guidelines

Since 2006, the following CPT category III code has been available for this procedure:

0123T - Fistulization of sclera for glaucoma, through ciliary body

This code was created to differentiate from CPT code 66155: Fistulization of sclera for glaucoma; thermo cauterization with iridectomy that filters aqueous fluid from the anterior chamber rather than the posterior chamber and usually requires an iridectomy.

Benefit Application

BlueCard/National Account Issues

Some state or federal mandates (e.g., FEP) prohibit plans from denying technologies that are approved by the U.S. Food and Drug Administration (FDA) as investigational. In these instances, Plans may have to consider the coverage eligibility of FDA-approved technologies on the basis of medical necessity alone.


A literature search conducted through July 2005 identified only 1 case series study by Singh and Singh of 147 patients treated with transciliary filtration (or fistulization) for the treatment of glaucoma followed up for up to 6 months. (1) The authors reported at 6 months that IOPs were reduced to 21 mm Hg or below without medication in 132 eyes. The decrease in IOP was statistically significant (p <0.02), and no cases of anterior chamber flattening occurred. Adverse events included the need for surgical revision in 7 patients 3 months after surgery, and choroidal effusion in 2 patients, which resolved within 1 month after surgery. No data on changes in vision or optic neuropathy were reported.

Periodic literature updates, most recently performed in November 2009, have identified little additional evidence on this procedure. No clinical trials were identified that were performed in the U.S. In 2008, Dow and Devencia reported use of tranciliary (Singh) filtration with the Fugo plasma blade in 60 eyes of 36 patients at a Philippine mission for indigent patients. (2) The authors propose that this procedure may be a possible answer for patients who do not have access to more complicated glaucoma procedures and/or medications. Filtration was performed on consecutive patients requiring surgical filtration surgery; 15 of the patients had pain due to high IOP and 24 had IOP greater than 50 mmHg. The average time required to perform the procedure was about 3 minutes. Postoperative IOP was compared with results from a published study on trabeculectomy versus thermosclerotomy with follow-up at 1 day, 1-3 months, and 6-12 months postoperatively. The results appeared similar to trabeculectomy, although the patients treated with tranciliary filtration and lost to follow-up at 6-12 months was greater than 50%. It was noted in the discussion that 14 eyes (23%) failed the procedure by 6 months, including all of the 5 eyes with neovascular glaucoma. This study is limited by the absence of a concurrent control, lack of detail in the reporting, and the loss to follow-up.

The limited literature since 2002 suggests poor acceptance of this procedure by the ophthalmologic community; the reasons for this are not clear. While this procedure is similar to other filtration procedures commonly performed for the surgical treatment of glaucoma and initial results appear promising, further studies with longer term follow-up are needed. Overall, the data are insufficient to determine the long-term health outcomes of transciliary fistulization for the treatment of glaucoma.


  1. Singh D, Singh K. Transciliary filtration using the Fugo Blade. Ann Ophthalmol 2002; 34(3):183-7.
  2. Dow CT, deVenecia G. Transciliary filtration (Singh filtration) with the Fugo plasma blade. Ann Ophthalmol 2008; 40(1):8-14.





CPT  0123T  Fistulization of sclera for glaucoma, through ciliary body 
ICD-9 Procedure  12.62  Thermocauterization of sclera with iridectomy 
ICD-9 Diagnosis  365.41 – 365.44  Glaucoma associated with congenital anomalies, dystrophies, and systemic syndromes 
  365.51 – 365.59  Glaucoma associated with disorders of the lens 
  365.60 – 365.65  Glaucoma associated with other ocular disorders 
  365.81 – 365.89  Other specified forms of glaucoma 
  365.9  Unspecified glaucoma 
HCPCS  No code   
ICD-10-CM (effective 10/1/13)    Investigational for all relevant diagnoses
   H40.50-H40.53 Glaucoma secondary to other eye disorders code range
  H40.81-H40.89 Other specified glaucoma code range
   H40.9 Unspecified glaucoma
   Q15.0-Q15.9 Glaucoma associated with congenital anomalies code range
ICD-10-PCS (effective 10/1/13)    ICD-10-PCS codes are only used for inpatient services.
   0856XZZ, 0857XZZ Surgical, eye, destruction, sclera, external, code by right or left
   08BC32Z, 08BD32Z Surgical, eye, excision, iris, percutaneous, code by right or left
Type of Service  Vision 
Place of Service  Outpatient Facility 


Fugo Blade for Glaucoma
Glaucoma, Transciliary Fistulization
Singh Filtration, Glaucoma
Transciliary Fistulization, Glaucoma

Policy History

Date Action Reason
09/27/05 Add policy to Other section, Vision subsection New policy
06/14/07 Replace Policy
Policy updated with literature search; policy statement unchanged.
01/14/10 Replace policy Policy updated with literature search through October 2009; reference 2 added; policy statement unchanged
2/10/11 Policy updated and archived Policy updated with literature search through December 2010; policy statement unchanged. Policy archived.

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