**2.4 Case 3**

A 67-year-old woman presented with AMD. Visual acuity in the right eye was finger count of 20 cm. Visual acuity in the left eye was 20/400 with visual disability. The patient was unable to read and cannot see faces. She was also unable to walk alone without serious problems in orientation and mobility.

Microperimetry showed an erratic fixation without a precise localization with central absolute scotoma and a sensitivity of 0.1 dB (**Figure 19**).

BCEA in the right eye was 185.08° squared in an erratic fixation (**Figure 20**).

**Figure 19.** *RE: Erratic fixation.*

**Figure 20.** *RE: BCEA 185.08° squared in erratic fixation.*

In the left eye, there was a central absolute scotoma with a sensitivity of 0.00 dB (**Figure 21**).

BCEA in the left eye was 192.82° squared (**Figure 22**).

After 10 sessions of audio-biofeedback, we obtained a shift of the erratic fixation in a new PRL, named TRL, localized inferiorly to the optic disk near the very large atrophic maculopathy, extended beyond the posterior pole, with a sensitivity of 0.7 dB instead of 0.1 dB at the start. The sensitivity of the retina in the new area of fixation reached a good value of intensity until 10 dB (**Figure 23**).

In the new area of fixation, the BCEA was 73.39° squared (**Figure 24**).

In the left eye, after audio-biofeedback, we obtained a new area of fixation in the same site of the right eye, below the optic disk and near the large atrophic macular degeneration with a sensitivity of 0.5 dB from the initial absence in the central absolute scotoma (**Figure 25**).

The BCEA of the new TRL was 99.6° squared (**Figure 26**).

Visual acuity in the right eye improved from finger count to 20/400. Visual acuity in the left eye improved from 20/400 to 20/250. Before rehabilitation, the patient was not able to read with electronic aid. After ABFB, she was able to read with CCTV. Furthermore, she was able to see more clearly when walking, see the number of days of months in the calendar without glasses, and look at photos of family members. When she was able to see her father's photo, she was moved!

Often in low-vision rehabilitation, we find a PRL localized very far from the atrophic fovea (**Figures 27** and **28**).

In other cases, the PRL may be closer to the atrophic fibrotic fovea (**Figure 29**). Still, in other cases, a very unstable foveal fixation must be stabilized (**Figure 30**). In this case, we used a custom target of fixation with a four-word phrase that the patient can read when presented in the best area of fixation.

**Figures 31** and **32** are examples of chessboard patterns used for audio-biofeedback.

Audio-biofeedback may be applied in other types of maculopathies such as hereditary retinal dystrophy, Stargardt disease, cone dystrophy, Best maculopathy, and myopic degeneration (**Figures 33**–**36**).

#### **Figure 23.**

*RE: Trained retinal locus localized inferiorly to the optic disk with a sensitivity of 0.7 dB instead of 0.1 dB before audio-biofeedback in the erratic fixation.*
