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Updated: Jun 30, 2026
08:38
Transretinal ERG Recordings from Mouse Retina: Rod and Cone Photoresponses
Published on: March 14, 2012
Rod and rod-driven function in achromatopsia and blue cone monochromatism
Anne Moskowitz1, Ronald M Hansen, James D Akula
1Department of Ophthalmology, Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA. anne.moskowitz@childrens.harvard.edu
Investigative Ophthalmology & Visual Science
|October 1, 2008
Summary
This study found that children with achromatopsia (ACHR) and blue cone monochromatism (BCM) exhibit reduced rod photoreceptor and postreceptor retinal function, indicating rod pathway involvement in these cone disorders.
Area of Science:
- Ophthalmology
- Retinal Physiology
- Electrophysiology
Background:
- Achromatopsia (ACHR) and blue cone monochromatism (BCM) are inherited retinal disorders primarily affecting cone function.
- Understanding the impact on rod photoreceptor and postreceptor retinal function is crucial for comprehensive patient management.
Purpose of the Study:
- To evaluate rod photoreceptor and postreceptor retinal function in pediatric patients with ACHR and BCM.
- To utilize contemporary electroretinographic (ERG) procedures for detailed functional assessment.
Main Methods:
- Studied 15 pediatric patients with ACHR and 6 with BCM.
- Obtained full-field electroretinogram (ERG) responses under scotopic and photopic conditions.
- Calculated rod photoreceptor (S(rod), R(rod)) and postreceptor (log sigma, V(max)) parameters, and oscillatory potential (OP) characteristics (log SOPA(1/2), SOPA(max)).
Main Results:
- Photopic responses were undetectable in ACHR and BCM patients, as anticipated.
- Significant reductions in scotopic photoreceptor (R(rod)) and postreceptor (V(max), SOPA(max)) amplitude parameters were observed compared to controls.
- An increased flash intensity (log sigma) was required for half-maximum b-wave amplitude, indicating altered rod-driven signaling.
Conclusions:
- Provides evidence of deficits in rod photoreceptor function in ACHR and BCM.
- Demonstrates impaired rod-mediated postreceptor function in these primary cone dysfunction syndromes.
- Highlights the involvement of the rod system in the pathophysiology of ACHR and BCM.
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