Evaluating medical students' proficiency with a handheld ophthalmoscope: a pilot study.

Introduction: Historically, testing medical students' skills using a handheld ophthalmoscope has been difficult to do objectively. Many programs train students using plastic models of the eye which are a very limited fidelity simulator of a real human eye. This makes it difficult to be sure that actual proficiency is attained given the differences between the various models and actual patients.

Changes in rod and cone-driven oscillatory potentials in the aging human retina.

Purpose: We recorded oscillatory potentials (OPs) to document how age impacts on rod- and cone-driven inner retina function.

Methods: Dark- and light-adapted electroretinogram (ERG) luminance-response functions were recorded in healthy human subjects aged 20 to 39, 40 to 59, and 60 to 82 years. Raw ERG traces (0.

Differential changes in retina function with normal aging in humans.

We evaluated the full field electroretinogram (ERG) to assess age-related changes in retina function in humans. ERG recordings were performed on healthy subjects with normal fundus appearance, lack of cataract and 20/20 acuity, aged 20-39 years (n = 27; mean age 25 ± 5, standard deviation), 40-59 years (n = 20; mean 53 ± 5), and 60-82 years (n = 18; mean 69 ± 5). Multiple ERG tests were applied, including light and dark-adapted stimulus-response function, dark adaptation and dynamic of recovery from a single bright flash under dark-adapted conditions.

The electroretinogram (ERG) of a diurnal cone-rich laboratory rodent, the Nile grass rat (Arvicanthis niloticus).

The most widespread models to study blindness, rats and mice, have retinas containing less than 3% cones. The diurnal rodent Arvicanthis niloticus retina has around 35% cones. Using ERG recordings, we studied retina function in this species.

Retinal anatomy and visual performance in a diurnal cone-rich laboratory rodent, the Nile grass rat (Arvicanthis niloticus).

Unlike laboratory rats and mice, muridae of the Arvicanthis family (A. ansorgei and A. niloticus) are adapted to functioning best in daylight.

Blindness caused by deficiency in AE3 chloride/bicarbonate exchanger.

Background: Vision is initiated by phototransduction in the outer retina by photoreceptors, whose high metabolic rate generates large CO2 loads. Inner retina cells then process the visual signal and CO2. The anion exchanger 3 gene (AE3/Slc4a3) encodes full-length AE3 (AE3fl) and cardiac AE3 (AE3c) isoforms, catalyzing plasma membrane Cl-/HCO3- exchange in Müller (AE3fl) and horizontal (AE3c) cells.