Noninvasive Ophthalmic Imaging Measures Retinal Degeneration and Vision Deficits in Ndufs4-/- Mouse Model of Mitochondrial Complex I Deficiency

Purpose: To characterize postnatal ocular pathology in a Ndufs4(-/-) mouse model of complex I deficiency using noninvasive retinal imaging and visual testing. Methods: Ndufs4(-/-) mice and wild-type (WT) littermates were analyzed at 3, 5, and 7 weeks postnatal. Retinal morphology was visualized by optical coherence tomography (OCT). OCT images were analyzed for changes in retinal thickness and reflectivity profiles. Visual function was assessed by electroretinogram (ERG) and optomotor reflex (OMR). Results: Ndufs4(-/-) animals have normal OCT morphology at weaning and develop innerplexiformlayer atrophy overweeks 5 to 7. Outer retinal layers showhyporeflectivity of the external limiting membrane (ELM) and photoreceptor ellipsoid zone (EZ). Retinal function is impaired at 3weeks, with profound deficits in b-wave, a-wave, and oscillatory potential amplitudes. The b-wave and oscillatory potential implicit times are delayed, but the a-wave implicit time is unaffected. Ndufs4(-/-) animals have normal OMR at 3 weeks and present with increasing acuity and contrast OMR deficits at 5 and 7 weeks. Physiological thinning of inner retinal layers, attenuation of ELM reflectivity, and attenuation of ERG b- and a-wave amplitudes occur inWT C57BL/6 littermates between weeks 3 and 7. Conclusions: Noninvasive ocular imaging captures early-onset retinal degeneration in Ndufs4(-/-) mice and is a tractable approach for investigating retinal pathology subsequent to complex I deficiency. Translational Relevance: Ophthalmic imaging captures clinically relevant measures of retinal disease in a fast-progressing mouse model of complex I deficiency consistent with human Leigh syndrome.