In geographic atrophy, RPE cells die, which causes photoreceptors
to degenerate, leading to vision loss.
Further studies in a mouse model of ciliopathy confirmed an important temporal relationship: Looking across several early development stages, the RPE defects preceded the photoreceptor
degeneration, which provides additional insights into ciliopathy-induced retinal degeneration.
Scientists at the University of Queensland in Australia have discovered a new type of cell that displays properties of both rod and cone photoreceptor
Most cases of incurable blindness occur due to the loss of millions of light-sensitive photoreceptor
cells that function like camera sensors.
- which decay in retinitis pigmentosa patients - differed in their fundamental structure when compared with those from family members.
In an adult animal, each LE contains more than a thousand ommatidia consisting of a conical lens below which are located 5-12 photoreceptors
, also called retinular cells, arranged like the sections of an orange.
The mutations affect the eyes' photoreceptors
, specialized cells in the retina that sense and convert light images into electrical signals sent to the brain.
Most people know at least a little about the retina, a thin tissue an inch in diameter that contains all the photoreceptor
cells responsible for beginning vision and their circuits that produce signals that become vision.
1,2) Foveal thinning and disruptions of the photoreceptor
inner and outer segment (IS/OS) junction are observed on spectral domain optical coherence tomography (SD-OCT).
Patients experiencing a retinal detachment are normally treated by surgical reattachment of the retina to reconnect the photoreceptors
with the RPE and prevent additional loss of vision.
In examining controls and exposed mice at postnatal day 60, the researchers found that late-born rod photoreceptors
and rod and cone bipolar cells increased by 16-30% in exposed offspring, whereas Muller glial cells (also classified as late-born retinal cells) did not increase.
Normally cells that respond to light, called photoreceptors
, pick up signals and transfer that information as nerve impulses to ganglion cells.