Resolution of retinal pigment epithelial detachment associated with exudative age-related macular degeneration following intravitreal ranibizumab therapy

Identifying the boundaries of retinal pigment epithelial detachments using two spectral-domain optical coherence tomography instruments

BACKGROUND AND OBJECTIVE

To compare two spectral-domain optical coherence tomography (SD-OCT) instruments in identifying the boundaries of retinal pigment epithelium detachment (PED).

PATIENTS AND METHODS

27 eyes were scanned with Cirrus and Spectralis SD-OCT instruments during a single visit. Two Cirrus scan patterns were used: the 512 × 128 and 200 × 200 covering a 6 × 6 mm (20° × 20°) area. The Spectralis scan pattern consisted of seven B-scans, averaged 51 times, covering a 30° × 5° area. The main outcome measures were the retinal thickness at the foveal center and the number of segmentation failures on the central B-scan.

RESULTS

The Spectralis algorithm failed to follow the proper retinal contour in 25 eyes (92.6%), while the segmentation on the Cirrus instrument was successful in every central B-scan. Spectralis yielded greater retinal thickness measurements in all cases, and the average difference between Cirrus and Spectralis was 139 μm (P < .001). The intraclass correlation coefficient between the two Cirrus scan patterns was 0.998, and Cirrus versus Spectralis was 0.21.

CONCLUSIONS

The Cirrus SD-OCT instrument identifies the appropriate segmentation boundaries in the presence PED. The Spectralis SD-OCT algorithm was unreliable in segmenting PEDs, leading to inaccurate retinal thickness measurements unless manual adjustments were performed.

Intravitreal bevacizumab for exudative age-related macular degeneration: effect on different subfoveal membranes

PURPOSE

The purpose of this study was to assess an association between specific types of subfoveal neovascularization and the change in visual acuity after intravitreal injections of bevacizumab (F. Hoffmann-La Roche AG, Basel, Switzerland) as treatment for exudative age-related macular degeneration.

METHODS

This retrospective clinical interventional comparative study included 307 patients (378 eyes) who received 3 consecutive intravitreal injections of bevacizumab at intervals of 2 months each. The study group was divided into eyes with a predominantly or purely classic type of subfoveal neovascular membrane (n = 81), those with an occult type with or without minimally classic subfoveal neovascularization (n = 232), and eyes with a detachment of the retinal pigment epithelium (n = 65).

RESULTS

The gain in best-corrected visual acuity did not vary significantly among the 3 subgroups at 2 months after baseline (P = 0.35 and P = 0.27), at 4 months after baseline (P = 0.63 and P = 0.56), or at the final follow-up at 7 months after baseline (P = 0.85 and P = 0.76). In multivariate linear regression analysis, the gain in best-corrected visual acuity at the final follow-up was significantly associated with the best-corrected visual acuity at baseline (P < 0.001). It was not significantly associated with age (P = 0.61), sex (P = 0.12), self-reported diabetes (P = 0.79), lens status (P = 0.84), or type of subfoveal neovascularization (P = 0.53).

CONCLUSION

After an intravitreal application of bevacizumab given as therapy for exudative age-related macular degeneration at 2-month intervals, the patient's gain in visual acuity did not depend on the type of the subfoveal neovascular membranes.