MOUNTAIN VIEW, Calif., Nov. 29 -- Iridex Corp. said a clinical study using its IRIS Medical OcuLight SLx laser further validates the effectiveness of transpupillary thermotherapy (TTT) for the treatment of wet age-related macular degeneration (AMD). The study, presented at the recent American Academy of Ophthalmology meeting in New Orleans, La., used TTT to treat 104 patients with occult neovascular membranes associated with wet AMD and showed stable or improved visual acuity in 79% of patients at 9 months follow-up. The study was a prospective, nonrandomized nonmasked case study performed by Allen B. Thach, Jack O. Sipperly, Pravin U. Dugel, Scott R. Sneed and Donald W. Park at Retinal Consultants of Arizona in Phoenix. One hundred and four patients were treated using the IRIS Medical OcuLight SLx and Large Spot Size Slit Lamp Adapter. Laser treatment consisted of a large laser spot adequate to cover the CNV lesion size, typically 3,000-6,000 micrometers diameter, delivered for 60 seconds at 600 to 1000 milliwatts. Patients were evaluated for visual acuity (stable or improved vision was defined as a loss of one line, any improvement in vision or no change in the vision) and the need for additional treatment. Of the 83 patients available for six-month follow-up (80%), visual acuity stabilized or improved in 63 patients (76%) and worsened (two or more line loss) in 20 patients (24%). Of the 48 patients followed for nine months (46%), visual acuity stabilized or improved in 38 patients (79%).