Multimodal Imaging Characteristics of ADRP in a Family with p.Thr58Arg Substituted RHO Mutation

Table 1

Full-field electroretinography (ERG) findings in the proband (mother) and son, all performed as per the ISCEV (International Society for Clinical Electrophysiology of Vision) standard. Flash stimuli are given in units of candela-seconds per square meter, and normative data were obtained from Diagnosys LLC.

	Mother OD	Mother OS	Son OD	Son OS	Normal range	Comments
Dark-adapted 0.01 cd∗s/m^2α-wave amplitude (μV)	−7.648	−6.063	−6.07	−7.459	−26.59 ± 21.72	Significant reductions in β-wave amplitudes suggest dysfunction at the level of the rod photoreceptor or inner retina
Dark-adapted 0.01 cd∗s/m^2β-wave amplitude (μV)	64.32	89	72.27	73.96	218.9 ± 117.2
Dark-adapted 3 cd∗s/m^2α-wave amplitude (μV)	−72.84	−100.1	−60.21	−60.31	−142.9 ± 75.12	Attenuation of mostly β-wave amplitudes in both patients is indicative of nonspecific photoreceptor dysfunction
Dark-adapted 3 cd∗s/m^2β-wave amplitude (μV)	87.08	122.3	64.65	61.07	269.4 ± 145.4
Dark-adapted 3 cd∗s/m^2α-wave implicit time	23.3	23.3	21.63	22.46	14.87 ± 4.89	α-wave and β-wave implicit time delays are an indicator of photoreceptor dysfunction, rather than a decrease in the total number of photoreceptors. In cases of photoreceptor number reduction (e.g., retinal detachment), amplitude reduction with normal implicit times would be expected
Dark-adapted 3 cd∗s/m^2β-wave implicit time	45.76	49.92	41.6	44.93	41.27s ± 11.55
Dark-adapted 10 cd∗s/m^2α-wave amplitude (μV)	−87.24	−133.2	−70.42	−76.67	−191.9 ± 73.2	Reductions in α-wave and β-wave amplitudes, taken together with the β-wave amplitude reduction on dim flash dark-adapted full-field ERG, indicate rod photoreceptor dysfunction rather than inner retinal layer dysfunction
Dark-adapted 10 cd∗s/m^2β-wave amplitude (μV)	108.9	153.7	74.28	56.53	309.7 ± 136.2
Light-adapted 3 cd∗s/m^2α-wave amplitude (μV)	−22.53	−27.08	−14.38	−14.17	−34.25 ± 25.13	Relative preservation of light-adapted response indicates pure rod or rod-cone dystrophy
Light-adapted 3 cd∗s/m^2β-wave amplitude (μV)	67.16	95.05	67.51	61.94	119.1 ± 66.48
30 Hz flicker trough-peak amplitude (μV)	62.59	77.76	53.94	45.71	108.1 ± 30.27	Attenuation of the 30 Hz flicker, taken together with the electrophysiologic findings above, allow for the diagnosis of rod-cone dystrophy in these patients