Comparing retinal reflectance changes elicited by transcorneal electrical retinal stimulation with those of optic chiasma stimulation in cats.
Summary of "Comparing retinal reflectance changes elicited by transcorneal electrical retinal stimulation with those of optic chiasma stimulation in cats."
To compare retinal reflectance changes (RCs) elicited by transcorneal electrical stimulation (TES) to those elicited by electrical stimulation of the optic chiasma (OX).
Two eyes of two cats were studied under general anesthesia. Biphasic electrical pulses at 20 Hz were applied for 5 ms in TES, and monophasic pulses were applied for 50 μs at 100 Hz in OX stimulation. Fundus images observed with near-infrared light (800-880 nm) were recorded every 25 ms for 26 s, beginning 2 s before and ending 20 s after the electrical stimulation. To improve the signal-to-noise ratio, the images of ten consecutive recordings were averaged. Two-dimensional topographic maps of the RCs were constructed by subtracting images before the stimulation from those after the stimulation. The electrically evoked potentials (EEPs) were recorded at the OX. The effect of an intravitreal injection of tetrodotoxin (TTX) on the RCs elicited by electrical stimulation was also determined.
After electrical stimulation, RCs were observed at the optic disc, retinal arteries, and retinal veins. The two-dimensional maps of the RCs elicited by both TES and OX stimulation were similar. The latency of the RCs ranged from 2.0 to 4.0 s, and the peak occurred 6 to 9 s after the onset of the ES. The intensity of the RCs was correlated with the amplitude of EEP elicited by TES stimulation. The RCs disappeared after the TTX injection in both TES and OX stimulation.
TES activates principally the retinal ganglion cells, and a change in the blood flow is initiated thereafter.
Topcon Research Institute, Itabashi, Japan.
This article was published in the following journal.
Name: Japanese journal of ophthalmology
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/21331693
- DOI: http://dx.doi.org/10.1007/s10384-010-0906-x
To identify which presenting features of rhegmatogenous retinal detachment (RRD) suggest the presence of multiple retinal breaks and to ascertain relevant patterns in retinal break location.
Pre-retinal arterial loops are usually incidental findings during examinations in healthy individuals. They are rarely associated with arterial occlusion, with only nine previously reported cases in t...
We investigated a case of unilateral optic nerve hypoplasia using spectral domain optical coherence tomography (SDOCT). Optical coherence tomography was done on both eyes using 5-line Raster scan for...
In recent times, glaucoma has become the leading cause of acquired blindness among the Japanese. As visual disorders markedly decrease the quality of life (QOL), it is important to develop new str...
A recent study of ophthalmologic patients found a strong association between fluoroquinolone use and retinal detachment. Given the prevalent use of fluoroquinolones, this could, if confirmed in the ge...
Transcorneal stimulation may enable neurons to survive degeneration processes via enhanced secretion of neurotrophic substances and direct stimulation of neurons.
The inner retina is crucially dependent on an adequate retinal blood supply. When the retina becomes ischemic and hypoxic this results in severe vision loss due to retinal neovascularizati...
The main objective of this observational study is to characterize and correlate functional and structural changes at the retinal level using the Retinal Leakage Analyzer (RLA) and the Opti...
The purpose of this study is to determine whether the structure and function of the human retina can be studied with high resolution in patients with inherited retinal degenerations using...
Ocular lesions, including cotton wool spots and retinal hemorrhage, are a common feature of HIV infection and acquired immunodeficiency syndrome (AIDS). The aetiology of these apparently v...
Medical and Biotech [MESH] Definitions
A group of rare, idiopathic, congenital retinal vascular anomalies affecting the retinal capillaries. It is characterized by dilation and tortuosity of retinal vessels and formation of multiple aneurysms, with different degrees of leakage and exudates emanating from the blood vessels.
Congenital, often bilateral, retinal abnormality characterized by the arrangement of outer nuclear retinal cells in a palisading or radiating pattern surrounding a central ocular space. This disorder is sometimes hereditary.
A metalloflavoprotein enzyme involved the metabolism of VITAMIN A, this enzyme catalyzes the oxidation of RETINAL to RETINOIC ACID, using both NAD+ and FAD coenzymes. It also acts on both the 11-trans- and 13-cis-forms of RETINAL.
INTERNEURONS of the vertebrate RETINA containing two processes. They receive inputs from the RETINAL PHOTORECEPTOR CELLS and send outputs to the RETINAL GANGLION CELLS. The bipolar cells also make lateral connections in the retina with the RETINAL HORIZONTAL CELLS and with the AMACRINE CELLS.
The inner portion of a retinal rod or a cone photoreceptor cell, situated between the PHOTORECEPTOR CONNECTING CILIUM and the synapse with the adjacent neurons (RETINAL BIPOLAR CELLS; RETINAL HORIZONTAL CELLS). The inner segment contains the cell body, the nucleus, the mitochondria, and apparatus for protein synthesis.