This case report presents canaloplasty as a bleb-free surgical option for lowering intraocular pressure in cases with postoperative conjunctival scarring.
Canaloplasty for Pigmentary Glaucoma with Coexisting Conjunctival Lymphoma
From the Glaucoma Service (PI, BB, LJK), the Oncology Service (CLS), and the Department of Pathology (RCE), Wills Eye Institute, Philadelphia, Pennsylvania.
The authors have no financial or proprietary interest in the materials presented herein.
Address correspondence to L. Jay Katz, MD, Glaucoma Service, Wills Eye Institute, 840 Walnut Street, Philadelphia, PA 19107. E-mail: email@example.com
Received: January 14, 2010
Accepted: December 02, 2010
Posted Online: February 10, 2011
Non-penetrating surgery has recently emerged as a potential alternative to traditional guarded filtration surgery in the surgical treatment of glaucoma.1,2 We report for the first time that canaloplasty can be considered as a surgical option when a trabeculectomy cannot be performed following excision of a conjunctival tumor.
A 72-year-old man with pigmentary glaucoma (previously diagnosed) underwent a trabeculectomy in his right eye in 1994. Visual acuity in both eyes was 20/20. Intraocular pressure (IOP) was 12 and 22 mm Hg in the right and left eyes, respectively. Gonioscopy showed an open angle with 2+ pigmentation in both eyes. Topical therapy included bimatoprost 0.03% at bedtime in both eyes and timolol 0.5% in morning in the left eye. Slit-lamp examination the right eye revealed an avascular bleb (Fig. 1A). The cup–disc ratio was 0.7 in both eyes (average sized disc). Humphrey visual field testing (central 24-2 threshold test) showed a nasal step in the right eye (mean deviation = −2.45 dB; pattern standard deviation = 6.78 dB) and an early superior arcuate defect in the left eye (mean deviation = −3.85 dB; pattern standard deviation = 3.43 dB). Retinal tomography showed a rim area of 0.60 mm2 in the right eye and 1.95 mm2 in the left eye.
Figure 1. (A) Slit-Lamp Photograph of the Left Eye Showing a Salmon-Colored Lymphoma in the Superior Fornix. (B) Slit-Lamp Photograph of the Left Eye Showing Scarred Superior Forniceal Conjunctiva Following Excision and Cryotherapy of Lymphoma. (C) Goniophotograph of the Left Eye Showing the Black 10-0 Polypropylene Suture in Schlemm’s Canal.
Biomicroscopy revealed a salmon-colored subepithelial conjunctival mass measuring 25 × 15 × 3 mm in the superomedial fornix of the left eye (Fig. 1A).The mass was completely excised and treated with adjuvant cryotherapy.3 Histopathology disclosed an extranodular marginal zone lymphoma of mucosa-associated lymphoid tissue.
Following excision, the IOP in the left eye remained elevated at 24 to 26 mm Hg. Surgical options included an inferior tube shunt or canaloplasty. Extensive postoperative superior conjunctival scarring precluded trabeculectomy (Fig. 1B). Non-penetrating Schlemm’s canaloplasty using the iScience cannula (iScience Interventional Inc., Menlo Park, CA) was performed (Fig.1B).4
Conjunctival peritomy was followed by creation of a 4.5 × 4.5 mm superficial partial-thickness scleral flap. A deep scleral flap, 0.5 mm smaller than the superficial one, was created to gain access to Schlemm’s canal by careful anterior dissection. Schlemm’s canal was unroofed and then both ostia of the canal were dilated with a microcannula and the iTrack microcatheter (iScience Interventional Inc.) was advanced in small steps into the complete circumference of the canal, injecting minuscule amounts of high viscosity viscoelastic every 1 or 2 clock-hours to dilate the canal to a width of approximately 300 μm. The iTrack microcatheter has an atraumatic distal tip that is illuminated by a helium-neon light source called the iLumin (Fig. 2). Ultrasound biomicroscopy was used intraoperatively to ensure that Schlemm’s canal was being dilated and not a collector channel. A 10-0 polypropylene suture was tied to the tip of the microcatheter that was retracted, pulling the suture into the canal. The polypropylene suture was tied down to provide a permanent traction to the trabecular meshwork followed by amputation of deep scleral flap. Superficial scleral flap and conjunctiva were sutured water tight.
Figure 2. iTrack 250 Flexible Microcatheter (photograph Courtesy of Iscience Interventional, Menlo Park, CA).
The IOP was lowered to 14 to 18 mm Hg with no glaucoma medications.
Glaucoma surgeons strive for bleb-free surgery, customizing glaucoma surgery for each individual eye. In this case of pigmentary glaucoma and coexisting conjunctival lymphoma,5 canaloplasty was successful following lymphoma resection. Canaloplasty has proven to be a bleb-free alternative to traditional glaucoma surgery, and we found it particularly beneficial in this case of postoperative conjunctival scarring.1,2
- Lewis RA, von Wolff K, Tetz M, et al. Canaloplasty: circumferential viscodilation and tensioning of Schlemm’s canal using a flexible microcatheter for the treatment of open-angle glaucoma in adults: interim clinical study analysis. J Cataract Refract Surg. 2007;33:1217–1226. doi:10.1016/j.jcrs.2007.03.051 [CrossRef]
- Shingleton B, Tetz M, Korber N. Circumferential viscodilation and tensioning of Schlemm canal (canaloplasty) with temporal clear corneal phacoemulsification cataract surgery for open-angle glaucoma and visually significant cataract: one year results. J Cataract Refract Surg. 2008;34:433–440. doi:10.1016/j.jcrs.2007.11.029 [CrossRef]
- Eichler MD, Fraunfelder FT. Cryotherapy for conjunctival lymphoid tumors. Am J Ophthalmol. 1994;118:463–467.
- U.S. Food and Drug Administration, Center for Devices and Radiologic Health. iScience Surgical Corporation Ophthalmic Microcannula. Summary of Safety and Effectiveness. 510(k) No. K041108. Rockville, MD: Author; June22, 2004. Available at: http://www.fda.gov/MedicalDevices/ProductsandMedicalProcedures/DeviceApprovalsandClearances/510kClearances/ucm090270.htm. Accessed on January 20, 2011.
- Shields CL, Shields JA, Carvalho C, Rundle P, Smith AF. Conjunctival lymphoid tumors: clinical analysis of 117 cases and relationship to systemic lymphoma. Ophthalmology. 2001;108:979–984. doi:10.1016/S0161-6420(01)00547-4 [CrossRef]