Intravitreal bevacizumab versus the conventional protocol of photodynamic therapy for treatment of chronic central serous chorioretinopathy

Authors


Young Hee Yoon, MD
Professor of Ophthalmology
Department of Ophthalmology
University of Ulsan
Asan Medical Center
#388-1 Poongnap-dong
Songpa-gu
Seoul
Korea Zip code 138-736
Tel: 82 02 3010 3675
Fax: 82 02 470 6440
Email: yhyoon@amc.seoul.kr

Editor,

Several recent studies have found photodynamic therapy (PDT) to be beneficial in the treatment of chronic central serous chorioretinopathy (CSC) (Chan et al. 2008; Maier et al. 2008; Orobia et al. 2008). To the same end, bevacizumab has also been investigated as a treatment for CSC in a recent pilot study. Torres-Soriano and colleagues reported that five patients with CSC showed functional and anatomical improvement after treatment with intravitreal bevacizumab (Torres-Soriano et al. 2008).

The present study investigated the efficacy of intravitreal bevacizumab compared with PDT to treat patients with chronic, recurrent types of CSC. This retrospective, nonrandomized, comparative case series included 29 patients who were considered to have chronic CSC when detachment of the macula persisted for at least 6 months or when the condition was associated with recurrent detachment. Patients with evidence of choroidal neovascularization were excluded after assessment by both indocyanine green angiography (ICGA) and fluorescein angiography (FA). No patient had a history of laser photocoagulation. Treatment modalities were selected by individual clinicians. In the bevacizumab-treated group, 16 patients received 1–7 intravitreal injections of bevacizumab (1.25 mg in 0.05 ml), guided by best-corrected visual acuity (BCVA) and optical coherence tomography (OCT) findings at 4- to 6-week intervals. The mean number of injections was 3.5 (±2.0). In the PDT-treated group, 13 patients received PDT using the standard dose of verteporfin (6 mg/m2). All PDT-treated patients received only a single treatment. The mean follow-up time for the bevacizumab-treated group was 7.3 months (±3.7 months) and that for the PDT-treated group 5.9 months (±3.5 months). The study was approved by the Institutional Review Board of the Asan Medical Center.

Table 1 shows the characteristics of the patients. In the bevacizumab-treated group, the mean Snellen BCVA improved from 0.49 to 0.66 and mean foveal thickness (FT) fell from 290 to 219 μm (p = 0.06 and p = 0.01, respectively). The PDT-treated group showed an improvement in mean Snellen BCVA from 0.43 at baseline to 0.65, and in mean FT from 332 to 171 μm, and 12 of 13 patients (92%) demonstrated complete resorption of subretinal fluid (SRF), at the 1-month follow-up visit. Seven of 13 eyes (53.8%) that underwent PDT had a FT of 171 μm or less. Such foveal thinning was thought to be associated with choriocapillary hypoperfusion in the PDT area, as shown by ICGA (Fig. 1).

Table 1.   Clinical characteristics of patients with chronic central serous chorioretinopathy (CSC).
 All eyes (n = 29)Photodynamic therapy (PDT) (n = 13)Bevacizumab (n = 16)p Value*
  1. * Mann–Whitney U test.

  2. Binomial test.

Mean age (years)48.2 (±7.8)49.7(±6.4)47.1(±7.9)0.50
Gender    
Male: Female21 (72.4%): 8 (27.6%)9 (69.2%): 4 (30.8%)12 (75%): 4 (25%) 
Mean number of episodes1.5 (±0.5)1.5 (±0.5)1.4 (±0.5)0.60
Mean duration of current episode (months)9.5 (±17.6)15.5 (±25.73)4.6 (±3.2)0.05
Mean baseline logMAR/Snellen best-corrected visual acuity (BCVA)0.34 (±0.23)/0.46 (±0.64)0.37 (±0.15)/0.43 (±0.82)0.32 (±0.28)/0.49 (±0.55)0.20
Mean baseline foveal thickness (μm)308 (±87)332 (±87)290 (±85)0.20
Mean follow-up period (months)6.2 (±3.9)5.9 (±3.5)7.3 (±3.7) 
Mean logMAR/Snellen BCVA at last follow-up 0.19 (±0.18)/0.65 (±0.66)0.18 (±0.26)/0.66 (±0.55)0.55
Mean foveal thickness at last follow-up (μm) 171 (±27)219 (±74)0.08
Number of patients with central foveal thickness (<172 μm) 7/13 (3.8%)4/16 (25.0%)0.024
Mean follow-up period (months)6.2 (±3.9)5.9 (±3.5)7.3 (±3.7) 
Figure 1.

 The eye of a 54-year-old man 3 months after treatment with photodynamic therapy (PDT). (A) Fundus photography. (B) Peak phase ICGA and (C) midphase ICGA show the area of choriocapillary hypoperfusion (3000 μm in width) after PDT. (D) OCT demonstrates absence of subretinal fluid but foveal thinning was evident.

Unlike what was noted after PDT treatment, bevacizumab-treated eyes revealed a rather slow and fluctuating visual recovery and developed either disease recurrence (four eyes) or drug resistance (three eyes) following repeat injection. Although seven bevacizumab-treated eyes showed persistent fluid at the last follow-up visit, there was no significant difference in the mean final BCVA between the bevacizumab- and PDT-treated groups (p = 0.55) (Fig. 2).

Figure 2.

 Comparison of the mean logMAR best-corrected visual acuity (BCVA) of patients treated with photodynamic therapy (blue line) or intravitreal bevacizumab injection (pink line) at the first month after treatment and at last follow-up.

In the present study, intravitreal bevacizumab, used in selected patients, was as effective as was PDT in treating chronic CSC, but the mean visual acuity increased significantly more in PDT-treated than in bevacizumab-treated patients. In terms of safety, foveal thinning occurred less frequently in bevacizumab-treated eyes than in PDT-treated eyes (25% versus 53%). However, it is possible that the low incidence of foveal thinning in the bevacizumab-treated group is attributable to the fact that bevacizumab treatment was not as effective as PDT. In addition, foveal thinning could be partly caused by the significantly longer macular detachment period evident in the PDT-treated group.

In conclusion, despite showing a slower and rather incomplete reduction in SRF, intravitreal bevacizumab seemed to be a safer and effective treatment option, compared with PDT, in selected patients; however, our results need to be further explored in studies with more patients and longer follow-up times.

Ancillary