inner nuclear layer


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inner nuclear layer

[TA]
the layer of the retina composed of the cell bodies of bipolar cells, horizontal cells, and some of the cell bodies of amacrine cells.
Synonym(s): stratum nucleare internum [TA]

retina 

The light-receptive, innermost nervous tunic of the eye. It is a thin transparent membrane (about 125 μm near the ora serrata, 350 μm near the macula and 560 μm near the optic disc). The retina proper has an area of about 266 mm2. It lies between the vitreous body and the choroid, and extends from the optic disc to the ora serrata. Near the posterior pole and temporal to the optic disc is the macula, at the centre of which is the foveola which provides the best visual acuity. The retina contains at least 10 distinct layers, of which there are two synaptic layers. They are from the outermost layer to the innermost: (1) the pigment epithelium; (2) the layer of rods and cones; (3) the external limiting membrane; (4) the outer nuclear layer; (5) the outer molecular (outer plexiform) layer; (6) the inner nuclear layer (which contains the bipolar, amacrine and horizontal cells and nuclei of the fibres of Mueller); (7) the inner molecular (inner plexiform) layer; (8) the ganglion cell layer; (9) the nerve fibre (layer stratum opticum); and (10) the internal limiting membrane. The two synaptic layers where visual signals must synapse as they emerge from the rods and cones on their way to the optic nerve are the two molecular layers (5 and 7) (Fig. R9). The blood supply to the retina is composed of the capillaries from the central retinal artery, which supply the inner two-thirds of the retina up to the outer plexiform layer, and the choriocapillaris, which supplies the outer one-third. There is no retinal circulation in the foveola (avascular zone). A blood-retina barrier is created by the walls of the retinal capillaries which restrict the movement of molecules, which could be damaging to neural tissue or interfere with function, from the inside to the outside of the capillaries. The blood-retina barrier in the outer third of the retina is formed by the tight junctions of the retinal pigment epithelium cells. See astrocytes; optic cup; optic disc; ectoderm; ocular fundus; fibre layer of Henle; macula; neurotransmitter; neurosensory retina; retinitis; retinopathy; rhodopsin; transduction.
converse retina See inverted retina.
fleck retina Term referring to a retina with multiple, small or yellow spots, which are seen in various conditions: actinic keratopathy, drusen, fundus albipunctatus, fundus flavimaculatus.
inverted retina Term referring to the fact that the retina of vertebrates is orientated so that the light has to pass through all the neuronal layers before reaching the photo-receptors. However, the retina of invertebrates is normally orientated so that light passes first through the photoreceptors as it traverses the retina: such a retina is called a verted or converse retina.
lattice degeneration of the retina 
A vitreoretinal degeneration usually found between the equator and the ora serrata leading to a thinning of the retina and characterized by a lesion made up of fine white lines and some pigmentation. It may result in holes or tears and in rhegmatogenous retinal detachment by which time the patient usually complains of floaters. The condition is most common in myopes and often found in patients with Marfan's syndrome. See retinal break; retinal detachment; retinoschisis; Marfan's syndrome.
leopard retina See leopard fundus.
neurosensory retina This is composed of all the layers of the retina, except the outer pigmented layer (called retinal pigment epithelium). It comprises three main groups of neurons: (1) the photoreceptors, (2) the bipolar cells, and (3) the ganglion cells. In addition, there are other connecting neurons: the horizontal and amacrine cells. The neurosensory layer is derived embryologically from the inner layer of the optic cup whereas the pigmented layer is derived from the outer layer of the optic cup and they are separated by a potential space which facilitates their separation, as occurs in detached retina. Syn. sensory retina.
tessellated retina See tessellated fundus.
tigroid retina See tessellated fundus.
verted retina See inverted retina.
Fig. R9 Schematic representation of the cells and layers of the central primate retina (1: retinal pigment epithelium; 2: layer of rods and cones; 3: external limiting membrane; 4: outer nuclear layer; 5: outer plexiform layer; 6: inner nuclear layer; 7: inner plexiform layer; 8: ganglion cell layer; 9: nerve fibre layer; 10: internal limiting membrane)enlarge picture
Fig. R9 Schematic representation of the cells and layers of the central primate retina (1: retinal pigment epithelium; 2: layer of rods and cones; 3: external limiting membrane; 4: outer nuclear layer; 5: outer plexiform layer; 6: inner nuclear layer; 7: inner plexiform layer; 8: ganglion cell layer; 9: nerve fibre layer; 10: internal limiting membrane)

Table R2 Some approximate retinal dimensions
diameter
structuremmdegreesdistance from centre of foveola
foveola0.41.3
fovea centralis1.55.0
macula lutea4.014
optic disc*
horizontal1.86.0
vertical2.17.5
nasal disc margin5.5 mm or 18.5
temporal disc margin3.5 mm or 12.5
centre of disc4.6 mm or 15.5
*The figures given for the size of the disc are those corresponding to the blind spot. Anatomically the optic disc is slightly smaller.
References in periodicals archive ?
The layers marked positive in the retina were the inner nuclear layer and the ganglion layer, reaching the maximum when the alevins were two days in hypoxia and minimum when the hypoxia is chronic.
Our study showed that there were increased intercellular space, decreased cell number in retinal ganglion cell layer with time, and thinner inner nuclear layer at week 12 in the diabetic rats.
Thanks to this software, we are able to obtain, at macular level, macular total retina, retinal nerve fiber layer, ganglion cell layer, inner plexiform layer, inner nuclear layer, outer plexiform layer, outer nuclear layer, retinal pigmented epithelium, inner retinal layers, and outer retinal layer thickness measurements in all sectors as defined by the Early Treatment Diabetic Retinopathy Study scheme (temporal inner, superior inner, nasal inner, inferior inner, temporal outer, superior outer, nasal outer, and inferior outer).
ILM, internal limiting membrane and inner border of the RNFL layer; RNFL, outer border of the retinal nerve fiber layer; GCL, outer border of the ganglion cell layer; IPL, outer border of the inner plexiform layer; INL, outer border of the inner nuclear layer; OPL, outer border of the outer nuclear layer; ELM, external limiting membrane--outer border of the outer nuclear layer; RPE, retina pigment epithelium; BM, Bruch's membrane.
Individual retinal layers are labeled: nerve fiber layer (NFL), ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer (INL), outer plexiform layer (OPL), outer nuclear layer (ONL), external limiting membrane (ELM), inner segments (IS), inner segment ellipsoid (ISe), outer segments (OS), retinal pigment epithelium (RPE), and choroid.
The ganglion cell layer as measured from the RNFL to the boundaries of the inner nuclear layer (GCL+) was found to be reduced in the nasal (40.96 [micro]m in controls vs 38.96 [micro]m in patients, p = 0.003) and temporal (52.31 [micro]m vs 49.20 [micro]m, p = 0.001) quadrants, in the nasal (40.96 [micro]m vs 38.96 [micro]m, p = 0.003), inferonasal (37.51 [m vs 35.57 [micro]m, p = 0.045), and temporal (52.31 [micro]m vs 49.20 [m, p = 0.001) sectors, and in total thickness (43.20 [micro]m vs 41.21 [micro]m, p < 0.001) (Table 2).
IS = inner segment, OS = outer segment, ONL = outer nuclear layer, INL = inner nuclear layer, OPL = outer plexiform layer, INL = inner nuclear layer, IPL = inner plexiform layer, and GCL = ganglion cell layer.
To evaluate the damage of retinal ischemia reperfusion, the thickness was measured including total retina thickness, the inner plexiform layer (IPL), the inner nuclear layer (INL), and outer nuclear layers (ONL) and the number of cells in the ganglion cell layer (GCL) was calculated using the linear cell density (cells per 200 [micro]m).
To be able to assess the contrast and distinction between the individual retinal layers, the following layer boundaries were manually annotated by a single investigator (DP) in Adobe Photoshop version CS6 (Figure 2): boundaries between vitreous and nerve fiber layer (NFL), border between nerve fiber layer and ganglion cell layer (GCL), border between inner plexiform layer and inner nuclear layer (INL), border between inner nuclear layer and outer plexiform layer (OPL), border between outer plexiform layer and outer nuclear layer (ONL), and border between outer nuclear layer and external limiting membrane (ELM).
The inner retina consists ofnerve fiber layer (NFL), ganglion cell layer (GCL), inner plexiform layer (IPL), and inner nuclear layer (INL).
The image of the macula within this circle was then manually segmented into three layers: the inner layer (nerve fiber layer and ganglion cell layer), middle layer (inner plexiform layer and inner nuclear layer), and outer layer (outer plexiform layer and outer nuclear layer) (Figure 1).
This study aimed at assessing the prevalence of pathologies presenting retinal inner nuclear layer (RINL) microcystic perimacular changes associated with optic nerve atrophy (OA).