Ghazi et al Table 1 Subgroup of 14 patients. GLD of the disciform scar in the fellow eyes and GLD of the neovascular lesion pre- and post-PDT in the study eyes Case number GLD pre-PDT (micron) GLD post PDT (micron) Size of disciform scar Comments on in fellow eye (micron) disciform scar 1 4400 0 6000 Following laser 2 1000 4800 9200 Following laser 3 2900 0 5200 Following laser 4 1800 6000 6200 5 3000 4800 6400 6 3000 2800 7000 7 4000 0 8000 8 1000 3400 4000 9 4200 0 5600 10 400 0 6400 Following laser 11 3600 0 4000 Following laser 12 2000 0 4400 13 2200 4300 2200 14 4800 4800 8000 Following laser Abbreviations: GLD, greatest linear dimension; PDT, photodynamic therapy. The size of the DS that could have potentially developed following PDT was determined from the study eyes of the subgroup of 14 patients, and then also from the rest of the study eyes (45 eyes) excluding the 3 that developed DS. It was found to be 3607 ± 1389 μm and 3579 ± 1473 μm, respectively (Table 2). In either case, it was signiﬁcantly smaller than the average size of the scar in the fellow eyes of the subgroup of 14 patients (5900 ± 1866 μm), and of the 8 of 14 without previous intervention (6200 ± 1493 μm) (Tables 2, 3). However, in both cases, it was not signiﬁcantly smaller than that of the 6 of 14 eyes that developed the scar following prior laser treatment (5500 ± 2365 μm) (Tables 2, 3). Discussion Photodynamic therapy is now one of the ﬁrst line treatment modalities used in the management of subfoveal CNV (VIP et al 2002). Its beneﬁt in reducing vision loss has been proven in the case of AMD-related predominantly classic SFCNV (TAP 1999; Bressler 2001), AMD-related occult SFCNV (VIP 2001b; Bressler 2002), and SFCNV related to pathologic myopia (VIP 2001a). Some evidence also exists for a treatment beneﬁt in other cases of SFCNV (Sickenberg et al 2000; Saperstein et al 2002; Busquets et al 2003). Although these clinical trials reported on the ﬂuorescein angiographic outcome following treatment and provided evidence that PDT could limit the size and progression of the CNV lesion, the main emphasis was on the reduction in the risk of moderate and severe visual loss associated with PDT. 776 The effect of treatment on the size of the CNV lesion, particularly the evolution of the DS potentially associated with it, was less extensively assessed. Our study exclusively discusses this treatment beneﬁt of PDT regardless of the ﬁnal visual outcome, and supports the idea that the latter should not be the sole criterion by which treatment success is determined. Over an average follow-up period of 9 months, we found that 64% of PDT treated eyes had stable or decreased GLD of the CNV lesion with no progression, 45% had no evidence of CNV with absence of leakage, and only 36% had progression at the last follow-up visit. These results compare favorably to those reported in the one-year follow up of the TAP trial (TAP 1999) where 19% of treated eyes had absence of leakage and 46% had progression. The explanation for this favorable outcome is two-fold. First, the majority of our study eyes had a lesion almost entirely composed of classic CNV (data not shown here). Although in a subgroup analysis in the TAP trial, lesion characteristics at baseline did not have a signiﬁcant effect on the magnitude of treatment beneﬁt on progression and ﬁnal lesion size more than 6 MPS disc areas, only three broad classes of lesions were analyzed: those with at least 50%, those with less than 50%, and those with no classic CNV. Those with at least 50% classic CNV were not further subdivided. Our group of study eyes constitutes one subgroup of those with at least 50% classic CNV and probably the one with the most favorable response to PDT as far as post-treatment lesion size and progression are concerned. Second, a selection bias, by virtue of the Clinical Ophthalmology 2008:2(4)