Optic cup

OBJECTIVE: To explore the underlying regional brain activity deficits in the visual cortex in patients with primary angle-closure glaucoma (PACG) relative to normal controls (NCs) using regional homogeneity (ReHo) method, and its relationship with behavioral performances. PATIENTS: Twenty PACG patients (10 females, 10 males; mean age ± standard deviation [SD]: 54.42±9.46 years) and 20 age-, and sex status-matched NCs (10 females, 10 males; mean age ± SD: 53.75±9...

Glaucoma is a heterogeneous group of diseases characterised by cupping of the optic nerve head and visual-field damage. It is the most frequent cause of irreversible blindness worldwide. Progression usually stops if the intraocular pressure is lowered by 30-50% from baseline. Its worldwide age-standardised prevalence in the population aged 40 years or older is about 3·5%. Chronic forms of glaucoma are painless and symptomatic visual-field defects occur late. Early detection by ophthalmological examination is mandatory...

Complement components have been implicated in a wide variety of functions including neurogenesis, proliferation, cell migration, differentiation, cancer, and more recently early development and regeneration. Following our initial observations indicating that C3a/C3aR signaling induces chick retina regeneration, we analyzed its role in chick eye morphogenesis. During eye development, the optic vesicle (OV) invaginates to generate a bilayer optic cup (OC) that gives rise to the retinal pigmented epithelium (RPE) and neural retina...

Purpose: Choroidal thinning has been associated with reticular pseudodrusen (RPD) and β-peripapillary atrophy (β-PPA), which have been linked to normal-tension glaucoma (NTG). This analysis sought to determine whether RPD are independently associated with β-PPA in early AMD patients. Secondary outcomes included the association of RPD and preexisting diagnosis of glaucoma, cup-to-disc ratio (CDR), subfoveal choroidal thickness (SFCT), and IOP. Methods: This prospective cross-sectional study examined 78 age- and sex-matched early AMD patients: 43 RPD patients (63 eyes) and 35 non-RPD patients (64 eyes)...

AIMS: We investigated the relationship between elevated intraocular pressure (IOP) and changes in global and peripapillary sector retinal nerve fiber layer (RNFL) thickness around the optic nerve head (ONH) in the laser-induced ocular hypertension monkey model. METHODS: To induce high IOP, green laser photocoagulation burns were applied around the trabecular meshwork of 1 eye from each of 12 cynomolgus monkeys. The animals had been acclimated to IOP measurement under conscious conditions for more than 2 months, and IOP was chronologically measured...

PURPOSE: To investigate optic nerve head (ONH) pallor quantitatively in patients with primary open-angle glaucoma (POAG) and in healthy subjects, and to examine the relationship to mean deviation in perimetry (MD), cup-disk ratio (CDR), and diameters of retinal vessels. METHODS: A total of 89 POAG patients (67.6 ± 11.1 years) and 48 healthy subjects (63.3 ± 14 years) were included. A dual-bandpass transmission filter was introduced in the illumination path of the fundus camera of the Dynamic Vessel Analyzer (Imedos Systems UG) and two monochromatic images at different wavelenghts (548 ± 10 and 610 ± 10 nm) were recorded simultaneously...

BACKGROUND: The retinal pigment epithelium (RPE) is a specialized monolayer of epithelial cells that forms a tight barrier surrounding the neural retina. RPE cells are indispensible for mature photoreceptor renewal and survival, yet how the initial RPE cell population expands around the neural retina during eye development is poorly understood. RESULTS: Here we characterize the differentiation, proliferation and movements of RPE progenitors in the zebrafish embryo over the period of optic cup morphogenesis...

PURPOSE: This paper aims at the description and comparison of methods of topographic analysis of racing courses at all disciplines of alpine skiing sports for the purposes of obtaining: terrain geomorphology (snowless and with snow), course geometry, and competitors' runs. METHODS: The review presents specific methods and instruments according to the order of their historical appearance as follows: (1) azimuth method with the use of a compass, tape and goniometer instruments; (2) optical method with geodetic theodolite, laser and photocells; (3) triangulation method with the aid of a tape and goniometer; (4) image method with the use of video cameras; (5) differential global positioning system and carrier phase global positioning system methods...

In vertebrates, the retinal pigment epithelium (RPE) and photoreceptors of the neural retina (NR) comprise a functional unit required for vision. During vertebrate eye development, a conversion of the RPE into NR can be induced by growth factors in vivo at optic cup stages, but the reverse process, the conversion of NR tissue into RPE has not been reported. Here, we show that bone morphogenetic proteins (BMP) signalling can reprogram the NR into RPE at optic cup stages in chick. Shortly after BMP application, expression of Microphthalmia associated transcription factor (Mitf) is induced in the NR and selective cell death on the basal side of the NR induces an RPE-like morphology...

PURPOSE: To describe the prevalence of vertical cup-to-disc ratio (vCDR) asymmetry in U.S. adults and assess the utility of vCDR asymmetry in the diagnosis of glaucoma. DESIGN: Cross-sectional study. PARTICIPANTS: A total of 5359 subjects aged ≥40 years from the 2005-2008 National Health and Nutrition Examination Survey (NHANES). METHODS: Subjects completed retinal photography and had vCDR determined in both eyes, with vCDR asymmetry calculated as the absolute value of the difference between the 2 eyes...

BACKGROUND: Accurate measurement of acetabular cup position (CP), changes in leg length (LL), and offset (OS) are paramount in ensuring proper sizing and implantation of components during total hip arthroplasty (THA). LL/OS inaccuracies can cause low back pain, neurological deficits, and patient dissatisfaction, while inaccurate positioning of the acetabular cup can lead to instability, dislocation, and, ultimately, revision surgery. The objective of this study was to evaluate the accuracy of a mini-navigation tool in measuring CP and LL/OS differential during THA...

AIM: to investigate neuromidin effectiveness in the treatment of patients with primary glaucoma and compensated intraocular pressure (IOP). MATERIAL AND METHODS: A total of 40 patients (80 eyes) were examined. Of them, 10 eyes with early glaucoma, 36 eyes with moderate-stage glaucoma, 33 eyes with advanced glaucoma, and 1 eye with end-stage glaucoma. In 19 eyes, IOP was controlled through beta-blockers, in 11 eyes - through carbonic anhydrase inhibitors, in 10 eyes - through prostaglandin analogues, and in 39 eyes - through combination drugs...

We introduce here a new technique for segmenting optic cup using two-dimensional fundus images. Cup segmentation is the most challenging part of image processing of the optic nerve head due to the complexity of its structure. Using the blood vessels to segment the cup is important. Here, we report on blood vessel extraction using first a top-hat transform and Otsu's segmentation function to detect the curves in the blood vessels (kinks) which indicate the cup boundary. This was followed by an interval type-II fuzzy entropy procedure...

Purpose: The purpose of this study was to measure change in anterior lamina cribrosa depth (ALD) globally and regionally in glaucoma eyes at different intraocular pressures (IOP). Methods: Twenty-seven glaucoma patients were imaged before and after IOP-lowering procedures using optical coherence tomography. The anterior lamina was marked in approximately 25 locations in each of six radial scans to obtain global and regional estimates of ALD. ALD and its change with IOP were compared with optic disc damage, nerve fiber layer thickness, and visual field loss...

Glaucoma is a heterogeneous group of diseases which all share retinal ganglion cell loss leading to a typical optic disc cupping and characteristic visual field defects. Glaucoma is the leading cause of irreversible blindness affecting 8.4 million people. In 2013, 65 million people suffered from glaucoma worldwide and the number will increase to about 112 million in 2040. This review provides an overview about the classification and genetic basics in glaucoma.

OBJECTIVES: The primary role of magnetic resonance imaging (MRI) in a patient with suspected optic neuropathy is to rule out nonischemic disorders, and many of the reported cases of ischemic optic neuropathy with positive neuroimaging are atypical forms of ischemic optic neuropathy. We studied the role of diffusion-weighted images of MRI in patients with ocular ischemia. METHODS: We describe the clinical, fundoscopic and neuroimaging characteristics of 3 patients with definite ocular ischemia related to occlusion of the carotid artery...

Here, this study reports a novel confined-space thermal dewetting strategy for the fabrication of Au nanocups with tunable diameter, height, and size of cup opening. The nanocup morphology is defined by the cup-shaped void space created by a yolk-shell silica template that spontaneously takes an eccentric configuration during annealing. Thermal dewetting of Au, which is sandwiched between the yolk and shell, leads to the desired nanocup morphology. With strong scattering in near infrared, the Au nanocups exhibit superior efficiency as contrast agents for spectral-domain optical coherence tomography imaging...

PurposeTo evaluate long-term structural and functional changes to the retina and optic nerve following panretinal photocoagulation (PRP) in diabetic retinopathy (DR) patients.MethodsParticipants were patients with DR requiring PRP and control patients with DR not requiring PRP. The Heidelberg retinal tomography (HRT) and optical coherence tomography (OCT) were performed to analyze the optic nerve and macula. Best-corrected visual acuity (BCVA) and visual field (VF) testing were done to measure central and peripheral vision...

HASH(0x49acd40)

In the study of adult stem cells and regenerative mechanisms, planarian flatworms are a staple in vivo model system. This is due in large part to their abundant pluripotent stem cell population and ability to regenerate all cell and tissue types after injuries that would be catastrophic for most animals. Recently, planarians have gained popularity as a model for eye regeneration. Their ability to regenerate the entire eye (comprised of two tissue types: pigment cells and photoreceptors) allows for the dissection of the mechanisms regulating visual system regeneration...