Efficacy of transpupillary thermotherapy (TTT) in the treatment of occult subfoveal choroidal neovascularization in age-related macular degeneration

Abstract

Transpupillary thermotherapy may stabilize visual acuity in a majority of patients with occult subfoveal choroidal neovascularization secondary to ARMD. Proof of therapeutic benefit is best determined by a randomized clinical trial that is currently underway (TTT4CNV).

Transpupillary thermotherapy for occult subfoveal choroidal neovascularization: a 1‐year, prospective randomized pilot study

“…In addition, the cut-off point for change differed between different studies. Some authors defined change of VA as a difference of three lines or 15 letters between two occasions (Algvere et al 2001(Algvere et al , 2003Friberg et al 2001;Haas et al 2003), whereas others used a drop or gain of one (Reichel et al 1999;Ahuja et al 2001;Kim et al 2001;Newsom et al 2001;Park et al 2001) or two lines from one visit to another as a criterion for changed VA (Thach et al 2003). It should also be pointed out that using VA as the only measure of visual outcome might be too crude.…”

“…In some of those studies the numbers of patients as well as the stabilization of VA in 38-71% were similar to the 62% in our study (Reichel et al 1999;Ciulla et al 2001;Friberg et al 2001;Newsom et al 2001;Haas et al 2003). Other studies included more patients, but the effect of treatment was evaluated using the natural course of disease as reported by others (Ahuja et al 2001;Algvere et al 2001Algvere et al , 2003Kim et al 2001;Park et al 2001;Thach et al 2003). As the natural course of the disease is poor and highly variable, any comparison of one study population with another must always be made with caution (Ergun & Stur 2001) could be that VA was measured differently from one study to another.…”

“…To date, no objective set-up parameters have been established, resulting in a random and rather subjective variation in set-up from user to user, which further emphasizes the difficulty in comparing study results. It has been suggested that the power should be reduced in a patient with a heavily pigmented fundus (Ahuja et al 2001;Kim et al 2001). All our patients had blue eyes and we used the same treatment settings for all of them.…”

“…As the natural course of the disease is poor and highly variable, any comparison of one study population with another must always be made with caution (Ergun & Stur 2001) could be that VA was measured differently from one study to another. Snellen charts were used in some studies (Reichel et al 1999;Ahuja et al 2001;Newsom et al 2001;Park et al 2001;Haas et al 2003;Thach et al 2003), whereas ETDRS charts were used in others (Algvere et al 2001(Algvere et al , 2003Kim et al 2001). Comparing differences in line reading instead of differences in numbers of letters provides less accuracy for statistical calculations (Ferris et al 1982).…”

“…As a treatment method, TTT is low cost, causes little discomfort for the patient and has few side-effects, although a few cases of over-treatment and epithelial tears have been reported, as has detachment of the membrane itself (Ahuja et al 2001;Thompson 2001;Benner et al 2002;Rumelt et al 2002;Salinas-Alaman et al 2003;Benhamou et al 2004;Gustavsson & Agardh 2004). Several studies have been performed since, some of which have suggested a positive effect (Ahuja et al 2001;Algvere et al 2001Algvere et al , 2003Friberg et al 2001;Kim et al 2001;Newsom et al 2001;Park et al 2001;Thach et al 2003), while others have been more negative (Mueller et al 2002;Haas et al 2003). As none of these studies included a control group, the aim of the present project was to perform a prospective, randomized, controlled study on the efficacy of TTT versus sham treatment for occult subfoveal CNV.…”