Advertisement

Rod Monochromatism (Achromatopsia)

  • Stephen H. Tsang
  • Tarun Sharma
Chapter
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 1085)

Abstract

  • Rod monochromatism (achromatopsia) is a congenital cone photoreceptor disorder, which is rare, affecting about 1 in 30,000 individuals. These patients have normal rod function but no detectable cone function; therefore, everything they see is in shades of gray (total color blindness). Patients usually present in infancy with nystagmus and photophobia. Vision is usually about 20/200 or worse; patients have a hyperopic refractive error. Some patients show paradoxical pupillary response; that is, the pupils dilate in bright light. Fundus examination is normal, though pigmentary mottling and atrophic changes may be observed at the macula.

  • Incomplete achromatopsia: Patients in this group have somewhat better visual acuity, about 20/80 to 20/120, with some residual functioning of cone photoreceptors. This milder form allows some color discrimination.

  • Complete achromatopsia: It occurs in about 4–10% of Pingelapese islanders, who live on one of the Eastern Caroline Islands of Micronesia.

Keywords

Autosomal recessive Rod monochromatism Achromatopsia 

Suggested Reading

  1. Greenberg JP, Sherman J, Zweifel SA, Chen RW, Duncker T, Kohl S, et al. Spectral-domain optical coherence tomography staging and autofluorescence imaging in achromatopsia. JAMA Ophthalmol. 2014;132:437–45.CrossRefGoogle Scholar
  2. Khan NW, Wissinger B, Kohl S, Sieving PA. CNGB3 achromatopsia with progressive loss of residual cone function and impaired rod-mediated function. Invest Ophthalmol Vis Sci. 2007;48:3864–71.CrossRefGoogle Scholar
  3. Sundaram V, Wilde C, Aboshiha J, Cowing J, Han C, Langlo CS, et al. Retinal structure and function in achromatopsia: implications for gene therapy. Ophthalmology. 2014;121:234–45.CrossRefGoogle Scholar

Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Jonas Children’s Vision Care, Bernard & Shirlee Brown Glaucoma Laboratory, Columbia Stem Cell Initiative-Departments of Ophthalmology, Biomedical Engineering, Pathology & Cell Biology, Institute of Human Nutrition, Vagelos College of Physicians and Surgeons, Columbia UniversityNew YorkUSA
  2. 2.Department of Ophthalmology, Columbia UniversityEdward S. Harkness Eye Institute, NewYork-Presbyterian HospitalNew YorkUSA

Personalised recommendations