Macular pigment and macular volume in eyes of patients with cystic fibrosis

Background. Because patients with cystic fi brosis (CF) are living longer, chronic malabsorption of carotenoids associated with CF resulting in decreased macular pigment (MP) may aff ect macular long-term health in later-life pathology. This study compared the macular pigment optical density (MPOD) and corresponding central macular volume (MV) of adult CF subjects and age-matched normal controls subjects to determine whether chronic malabsorption associated with CF could adversely aff ect macular photoreceptor anatomy. Objective. Our aim was to compare MPOD with measurements of central MV in CF patients with age-matched controls. Design. In nine adult CF patients (ages: 29 -46) without a history of carotenoid supplementation or known retinal or optic nerve disease MPOD and MV were measured by heterochromatic fl icker photometry (HFP) and optical coherence tomography (OCT), respectively, and compared to results obtained from 14 age-matched controls. Results. MPOD was signifi cantly reduced at 15' and 30' eccentricities in CF subjects compared to normal subjects (mean diff erence -0.21 at 15', -0.25 at 30', p < 0.005). No signifi cant diff erence, in MV noted at any of the eccentricities tested between CF and normal subjects (CF: normal MV ratios ranged from 0.94 to 1.1 for all eccentricities with p > 0.1 at all eccentricities). Best corrected vision acuity and fundus examination were normal in all subjects. Conclusions. Unsupplemented CF patients have markedly lower levels of macular carotenoids (e. g., lutein and zeaxanthin), but well-maintained visual function and no signifi cant reductions in central MV primarily composed of macular photoreceptors. Future studies are needed to determine whether the lifelong decrease in protective central retinal carotenoids predisposes CF patients to later-life retinal pathology.