|Home | About | Journals | Submit | Contact Us | Français|
Surgical iridectomy is a standard method of treatment for narrow‐angle glaucoma.1 However, the development of laser iridectomy has largely replaced the need for incisional surgery.1 There are cases where patients are unable or unwilling to submit to laser iridotomy, when surgical manipulation of the iris is required and when the cornea is not sufficiently clear. This case demonstrates the first use of a 25‐gauge aspiration cutter through a 1 mm self‐sealing corneal incision to perform a surgical iridectomy for glaucoma.
An 80‐year‐old woman was noted to have a variably pigmented inferonasal iris tumour, lenticular pseudoexfoliation and narrow angles in her left eye. The tumour was documented to grow and cause a sector cataract (prompting her referral to The New York Eye Cancer Centre, New York City, New York, USA). Ophthalmic examination included a 35 MHz high‐frequency ultrasound (ultrasound biomicroscopy) in movie mode. Both her narrow angles and tumour were evaluated (fig 11).
This study conformed to the tenets of the Declaration of Helsinki2 and the Health Insurance Portability and Accountability Act of 1996.3 The Finger iridectomy technique (FIT) was performed for glaucoma immediately after an FIT the iris tumour biopsy was found positive for melanoma.4 A 0.3 forceps was used to stabilise the eye at the limbus. A 25‐gauge trochar was used to create an incision through clear juxta‐limbal cornea into the anterior chamber. The first incision was made on the same side as the tumour to avoid the pupil and lens. Acetylcholine chloride 10 mg/ml was introduced to induce miosis, then sodium hyaluronate 1% was filled to maintain the anterior chamber.
For iridectomy, a second 25‐gauge incision was made in the superotemporal cornea.5
Using sodium hyaluronate 1%, the aspiration cutter was inserted and the port rotated for occlusion by the superonasal iris stroma. Aspiration cutting (suction of 300 mm Hg and cutting rate of 600 cuts/min) was used to perform a single full‐thickness superonasal iridectomy (fig 11).). Once engaged with iris tissue, aspiration, cutting and full‐thickness iridectomy are almost instantaneous. At the end of surgery, the sodium hyaluronate 1% was removed, and peribulbar antibiotic‐steroid and topical ocular hypotensive agents were used. No adverse side effects were noted.
At 3 weeks after iridectomy, slit‐lamp photography and high‐frequency ultrasound were used to document the patient's patent iridectomy and deepening of her anterior chamber (fig 11)) Her intraocular pressure decreased by 5 mm Hg (off medications).
A review of the literature shows that relatively large aspiration cutters have been used to perform iridectomy.6 For example, Ghanem et al6 used an aspiration cutter during phacoemulsification in patients with iridoschisis. The FIT is different in that it is a minimally invasive approach using a smaller 25‐gauge aspiration cutter probe to perform localised iridectomy through a self‐sealing 25‐gauge incision. No large incision, irrigation or sutures are required in FIT.4,5
The FIT introduces the concept of using a 25‐gauge aspiration cutter to perform a minimally invasive iridectomy for glaucoma. Unlike standard surgical iridectomy, the FIT 25‐gauge corneal incision allows for a relatively safe self‐sealing corneal wound.
Funding: This work was supported by The EyeCare Foundation, New York City, NY, USA.
Competing interests: None.