ABSTRACT
Transpupillary thermotherapy (TTT) is a method of delivering radiation to intraocular structures through the pupil. TTT has been used successfully as a primary treatment for small choroidal melanomas. A new and promising application of TTT is for the treatment of subfoveal choroidal neovascularization (CNV) caused by age-related macular degeneration. In TTT, the difficulty of delivering hyperthermia to the target tissue is obviated, as the anatomy of the eye allows direct access to the posterior segment structures. The decreased thermal effect in TTT compared with conventional laser photocoagulation seems to result in less damage to the adjacent retina – a finding that is important in cases with a subfoveal component to the neovascular complex. The near-infrared wavelength of the diode laser is well suited to treating lesions that are partially obscured by pigment or hemorrhage. The adjustable spot size is ideal for treating occult CNV, which tends to be larger than the 200–500µm spot size of conventional laser delivery systems.
