Abstract
Abstract: :
Purpose: Lasers have been used to treat symptomatic blebs that are excessively large or that overhang the cornea. However, laser treatment of blebs that dissect into the palpebral fissure has not been reported. We describe the unique use of krypton laser to treat nasally and temporally dissected blebs and discuss treatment outcomes. Methods: Retrospective review. Briefly, the technique employed krypton green light at power settings of 300 to 900 mW and duration of 0.1-0.5 seconds. After light epithelial abrasion and rose bengal staining of the treatment area, 500 µm spots were delivered to the dissected bleb. Treatment was repeated when necessary. Success was determined by a relative flattening of the treated area and the resolution of symptoms without loss of intraocular pressure (IOP) control. Patients were followed indefinitely or until they required additional procedures for their bleb dysfunction. Results: Thirteen consecutive patients from January 1996 to September 2001 underwent a total of 18 laser bleb reductions using an average of 181 spots per patient. Mean follow-up was 10.8 months (range: 1.5 months to 4 years). Eight cases (62%) were treated successfully, and 5 patients (38%) failed treatment. Persistent symptomatic dissection was the most common reason for failure (4 of 5 cases); one patient's IOP became uncontrolled, requiring a Baerveldt glaucoma implant. Other failures were managed with autologous blood injections (2 cases), surgical bleb revision with conjunctivoplasty (1 case), and aggressive lubrication (1 case). Seventy-five percent of those treated successfully remained off aqueous suppressants; 2 patients required a topical beta-blocker. The mean IOP (with or without drops) increased from 9.2 mmHg before treatment to 12.4 mmHg at the end of follow-up. Mild-to-moderate intraoperative discomfort was noted during 3 of the 18 treatments (17%). One bleb was Seidel positive (trace) immediately after treatment. Postoperative complications were brief and consisted of mild injection (28%) and pain (15%). Two patients (one success, one failure) developed spontaneous dissection on the untreated side of the bleb 1 and 10 weeks postoperatively. Conclusions: Krypton laser bleb reduction may be a useful initial treatment modality for symptomatic bleb dissection. Success rates may be modest, but most adverse effects are mild and/or transient, and most patients experience only a minimal rise in IOP. Therefore, this treatment provides a relatively low risk-benefit ratio compared to more invasive techniques such as blood injection or surgical revision. Importantly, however, significant loss of IOP control can occasionally occur.
Keywords: 357 clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials • 454 laser • 444 intraocular pressure