Figure 2. Fundus photographs and electroretinography results of the proband with X-linked retinitis pigmentosa,. The bone spicule pigmentation and attenuated retinal vessels can be seen bilaterally. Both the rod and cone electroretinogram amplitudes were below 10% of normal electroretinography (ERG; norms for scotopic [skot] ERG: b-wave 27.6 μV±5.2; norms for photopic [phot] ERG: b-wave 70 μV±8.9). Abbreviations: div means division.