Figure 1

Ocular and electrodiagnostic findings in a patient with SLC38A8-associated disease (proband 2). (a,b) Anterior segment photographs of right (a) and left (b) eyes obtained at age 14 years. The arrows mark the location of the embryotoxa. (c,d) Linear optical coherence tomography (OCT) scan through the centre of the macula of the left eye demonstrating absence of the foveal depression in keeping with foveal hypoplasia. (c) The associated left colour fundus photograph highlighting the location of the scan (line in the middle of the green box) is also shown. This image (d) reveals that, although the central macula appears to be adequately pigmented, there is a degree of fundal hypopigmentation mid-peripherally. It is noteworthy that the proband is of white British background and her skin was not hypopigmented in the context of her family. These images were obtained when the patient was 12 years of age. (e) Monocular pattern and flash visual evoked potentials (VEPs) recorded from electrodes mounted 3 cm to right (O2) and left (O1) of midline. The patient was 14 years old at the time of testing. The difference plots are subtractions of left from right scalp recordings to show how scalp asymmetry is reversed in the two eyes (crossed asymmetry) when virtually all optic nerve fibres cross at the chiasm. (f) Difference plots recorded at age 9 months and 2.5 years, showing minimal or no crossed asymmetry; this is in contrast to the assessment at age 14 years, shown in (e), which was in keeping with marked crossed asymmetry.