Table 1

Minimal values for ERG recordings: 100 μV for the photopic ERG, 150 μV for the scotopic ERG with a white stimulus after 12 minutes of dark adaptation, 170 μV for the scotopic ERG with a blue stimulus after 15 minutes of dark adaptation

NumberGenotypeAgeAge of onset (years)Initial symptomVisual acuity (1995)FunduscopyPhotopic ERG (μV)Scotopic ERG (μV) whiteScotopic ERG (μV) blue
right eyeleft eyeright eyeleft eyeright eyeleft eye
IV-3HTZ8412Decrease in visual acuityCFMarked central chorioretinal atrophy and mild chorioretinal atrophy in the mid-periphery. No abnormalties of the vessels and the optic disc. No bone spicules.000000
IV-7HTZ7420Decrease in visual acuityCFMarked central chorioretinal atrophy and irregular hyperpigmentation of the pigment epithelium in the posterior pole. Patchy chorioretinal atrophy in the mid-periphery. Temporal paleness of the optic disc.2030007530
V-3HMZ596Night blindnessLPCentral and mid-peripheral chorioretinal atrophy, mid-peripheral bone spicules, narrow vessels, and a “waxy” pale optic disc.NPNPNPNPNPNP
V-5HTZ5615Decrease in visual acuityCFCentral chorioretinal atrophy with irregular hyperpigmentation of the retinal pigment epithelium. No mid-peripheral abnormalities.3020005030
V-8HMZ517Night blindnessLPMarked central chorioretinal atrophy, mid-peripheral bone spicules and diffuse chorioretinal atrophy. Severe narrowing of the retinal vessels and temporal paleness of the optic disc.20400000
V-9HMZ507Night blindnessLPMarked central and mid-peripheral atrophy, with central hyperpigmentation and mid-peripheral bone spicules, narrow vessels, and paleness of the optic disc.0800000
V-10HTZ4812Decreased visual acuityCFCentral chorioretinal atrophy with focal hyperpigmentation. No bone spicules and no abnormalities of the vessels and the optic disc.30500000
V-11HTZ4612Grey spot in the central field of visionCFCentral chorioretinal atrophy with focal hyperpigmentation. Small round patches of chorioretinal atrophy with mild hyperpigmentation in the mid-periphery. Mild temporal paleness of the optic disc.8080007530
V-12HMZ436Night blindnessHMCentral chorioretinal atrophy with patchy atrophy in the mid-periphery. Bone spicules, narrow vessels, and a pale optic disc.20550000
  • HTZ = compound heterozygosity for IVS30+1g→t and IVS40+5g→a mutation; HMZ = homozygosity for IVS30+1g→t mutation; CF = counting fingers; HM = hand movements; LP = light perception; NP = not performed.