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Optic cup development

Jinzhao Song, Vikram Pandian, Michael G Mauk, Haim H Bau, Sara Cherry, Laurence C Tisi, Changchun Liu
Rapid and quantitative molecular diagnostics in the field, at home, and at remote clinics is essential for evidence-based disease management, control, and prevention. Conventional molecular diagnostics requires extensive sample preparation, complex instruments, and skilled personnel, restricting its use to centralized laboratories. To overcome these limitations, we designed a simple, inexpensive, hand-held, smartphone-based mobile detection platform, dubbed "smart-connected cup" (SCC), for rapid, connected and quantitative molecular diagnostics...
March 15, 2018: Analytical Chemistry
Jennifer C Hocking, Jakub K Famulski, Kevin H Yoon, Sonya A Widen, Cassidy S Bernstein, Sophie Koch, Omri Weiss, Seema Agarwala, Adi Inbal, Ordan J Lehmann, Andrew J Waskiewicz
The eye primordium arises as a lateral outgrowth of the forebrain, with a transient fissure on the inferior side of the optic cup providing an entry point for developing blood vessels. Incomplete closure of the inferior ocular fissure results in coloboma, a disease characterized by gaps in the inferior eye and recognized as a significant cause of pediatric blindness. Here, we identify eight patients with defects in tissues of the superior eye, a congenital disorder that we term superior coloboma. The embryonic origin of superior coloboma could not be explained by conventional models of eye development, leading us to reanalyze morphogenesis of the dorsal eye...
March 9, 2018: PLoS Genetics
X Fan, L L Wu, G G Xiao, Z Z Ma, F Liu
Objective: To analyze potentials of frequency-doubling technology perimetry (FDP) for diagnosing open-angle glaucoma (OAG) in perimetrically normal eyes of OAG patients diagnosed with standard automated perimetry (SAP) and relating factors from abnormalities on FDP to visual field loss on SAP. Methods: A prospective cohort study. Sixty-eight eyes of 68 OAG patients visiting the ophthalmic clinic of Peking University Third Hospital during November 2003 and October 2007 [32 primary open-angle glaucoma patients and 36 normal tension glaucoma patients, 32 males and 36 females, with an average age of (59±13) years] with unilateral field loss detected by SAP (Octopus101 tG2 program) were examined with the FDP N-30 threshold program (Humphrey Instruments) at baseline...
March 11, 2018: [Zhonghua Yan Ke za Zhi] Chinese Journal of Ophthalmology
Gaia Gestri, Naiara Bazin-Lopez, Clarissa Scholes, Stephen W Wilson
Coloboma is a defect in the morphogenesis of the eye that is a consequence of failure of choroid fissure fusion. It is among the most common congenital defects in humans and can significantly impact vision. However, very little is known about the cellular mechanisms that regulate choroid fissure closure. Using high-resolution confocal imaging of the zebrafish optic cup, we find that apico-basal polarity is re-modeled in cells lining the fissure in proximal to distal and inner to outer gradients during fusion...
2018: Frontiers in Cellular Neuroscience
Zhixi Li, Yifan He, Stuart Keel, Wei Meng, Robert T Chang, Mingguang He
PURPOSE: To assess the performance of a deep learning algorithm for detecting referable glaucomatous optic neuropathy (GON) based on color fundus photographs. DESIGN: A deep learning system for the classification of GON was developed for automated classification of GON on color fundus photographs. PARTICIPANTS: We retrospectively included 48 116 fundus photographs for the development and validation of a deep learning algorithm. METHODS: This study recruited 21 trained ophthalmologists to classify the photographs...
March 2, 2018: Ophthalmology
Mae O Gordon, Michael A Kass
PURPOSE: To utilize results from the Ocular Hypertension Study that can aid patients and clinicians to make evidence based decisions about the management of ocular hypertension DESIGN: 1636 participants with ocular hypertension were randomized to treatment with topical ocular hypotensive treatment or close observation. The goal of treatment was a 20% reduction in intraocular pressure and an intraocular pressure of < 24 mmHg. After a mean of 7.5 years, participants in the observation group also received treatment...
February 28, 2018: American Journal of Ophthalmology
Mohsin H Ali, Mark S Dikopf, Anthony G Finder, Ahmad A Aref, Thasarat Vajaranant, Jose de la Cruz, Maria Soledad Cortina
PURPOSE: To investigate glaucomatous damage in Boston keratoprosthesis type I (KPro) patients through structural analysis of the optic nerve head and digital planimetric quantification of Goldmann visual fields, a novel method of monitoring perimetric changes in KPro patients. METHODS: Records of patients undergoing KPro implantation from 2007 to 2015 at a single institution were reviewed. Parameters related to glaucoma status and KPro outcomes were analyzed. RESULTS: Twenty-two eyes from 21 patients met inclusion criteria, with mean follow-up of 49...
February 22, 2018: Cornea
Hadi S Hosseini, Larry A Taber
In the vertebrate embryo, the eyes develop from optic vesicles that grow laterally outward from the brain tube and contact the overlying surface ectoderm. Within the region of contact, each optic vesicle and the surface ectoderm thicken to form placodes, which then invaginate to create the optic cup and lens pit, respectively. Eventually, the optic cup becomes the retina, while the lens pit closes to form the lens vesicle. Here, we review current hypotheses for the physical mechanisms that create these structures and present novel three-dimensional computer (finite-element) models to illustrate the plausibility and limitations of these hypotheses...
February 9, 2018: Progress in Biophysics and Molecular Biology
Jeong-Ah Kim, Tae-Woo Kim, Robert N Weinreb, Eun Ji Lee, Michaël J A Girard, Jean Martial Mari
Although early diagnosis and treatment reduce the risk of blindness from glaucoma, the decision on whether or not to begin treatment in patients with suspected glaucoma is often a dilemma because the majority of patients never develop definite glaucoma. A growing body of evidences suggests that posterior bowing of the lamina cribrosa (LC) is the earliest structural change preceding the retinal nerve fiber layer (RNFL) loss in glaucomatous optic neuropathy. Based on this notion, we conducted a prospective study enrolling 87 eyes suspected of having glaucoma to investigate whether the future rate of RNFL loss is associated with the baseline LC curve evaluated by measuring the LC curve index (LCCI) using enhanced depth imaging optical coherence tomography...
January 15, 2018: Scientific Reports
M A Fernandez-Granero, A Sarmiento, D Sanchez-Morillo, S Jiménez, P Alemany, I Fondón
Glaucoma is a degenerative disease that constitutes the second cause of blindness in developed countries. Although it cannot be cured, its progression can be prevented through early diagnosis. In this paper, we propose a new algorithm for automatic glaucoma diagnosis based on retinal colour images. We focus on capturing the inherent colour changes of optic disc (OD) and cup borders by computing several colour derivatives in CIE L∗a∗b∗ colour space with CIE94 colour distance. In addition, we consider spatial information retaining these colour derivatives and the original CIE L∗a∗b∗ values of the pixel and adding other characteristics such as its distance to the OD centre...
2017: Journal of Healthcare Engineering
Kazuko Omodaka, Guangzhou An, Satoru Tsuda, Yukihiro Shiga, Naoko Takada, Tsutomu Kikawa, Hidetoshi Takahashi, Hideo Yokota, Masahiro Akiba, Toru Nakazawa
PURPOSE: This study aimed to develop a machine learning-based algorithm for objective classification of the optic disc in patients with open-angle glaucoma (OAG), using quantitative parameters obtained from ophthalmic examination instruments. METHODS: This study enrolled 163 eyes of 105 OAG patients (age: 62.3 ± 12.6, mean deviation of Humphrey field analyzer: -8.9 ± 7.5 dB). The eyes were classified into Nicolela's 4 optic disc types by 3 glaucoma specialists...
2017: PloS One
Aara Patel, Jane C Sowden
Embryonic development of the vertebrate eye begins with the formation of an optic vesicle which folds inwards to form a double-layered optic cup with a fissure on the ventral surface, known as the optic fissure. Closure of the optic fissure is essential for subsequent growth and development of the eye. A defect in this process can leave a gap in the iris, retina or optic nerve, known as a coloboma, which can lead to severe visual impairment. This review brings together current information about genes and pathways regulating fissure closure from human coloboma patients and animal models...
November 29, 2017: Seminars in Cell & Developmental Biology
Floria I Lupu, Jacob B Burnett, Jonathan T Eggenschwiler
Cell cycle-related kinase (CCRK) is a conserved regulator of ciliogenesis whose loss in mice leads to a wide range of developmental defects, including exencephaly, preaxial polydactyly, skeletal abnormalities, and microphthalmia. Here, we investigate the role of CCRK in mouse eye development. Ccrk mutants show dramatic patterning defects, with an expansion of the optic stalk domain into the optic cup, as well as an expansion of the retinal pigment epithelium (RPE) into neural retina (NR) territory. In addition, Ccrk mutants display a shortened optic stalk...
February 1, 2018: Developmental Biology
Ana Garrido-Varo, María-Teresa Sánchez, María-José De la Haba, Irina Torres, Dolores Pérez-Marín
Near-Infrared (NIR) Spectroscopy was used for the non-destructive assessment of physico-chemical quality parameters in olive oil. At the same time, the influence of the sample presentation mode (spinning versus static cup) was evaluated using two spectrophotometers with similar optical characteristics. A total of 478 olive oil samples were used to develop calibration models, testing various spectral signal pre-treatments. The models obtained by applying MPLS regression to spectroscopic data yielded promising results for olive oil quality measurements, particularly for acidity, the peroxide index and alkyl and ethyl ester content...
November 16, 2017: Sensors
Imtiaz Ali Shah, Shujaat Ali Shah, Partab Rai Nagdev, Safdar Ali Abbasi, Naeem Ali Abbasi, Safdar Akhtar Katpar
BACKGROUND: Pigment Dispersion Syndrome (PDS) is an autosomal dominant disorder of white males between 20 to 40 years of age characterized by deposition of pigment on the lens, zonules of lens, trabecular meshwork and corneal endothelium (Krukenberg's spindle) in addition to radial, spoke like transillumination defects in the mid peripheral iris. This study was conducted to determine the frequency of occurrence of Pigmentary Glaucoma in patients with Pigment Dispersion Syndrome (PDS)...
July 2017: Journal of Ayub Medical College, Abbottabad: JAMC
Young Kook Kim, Ahnul Ha, Won June Lee, Jin Wook Jeoung, Ki Ho Park
PURPOSE: To introduce the measurement method of optic disc cup surface depth using spectral-domain optical coherence tomography (SD-OCT) and then evaluate the rates of cup surface depression at 3 different stages of glaucoma. MATERIALS AND METHODS: We retrospectively identified 52 eyes with preperimetric glaucoma, 56 with mild-or-moderate glaucoma and 50 with severe glaucoma and followed them for at least 48 months. Eyes were imaged using SD-OCT (Cirrus HD-OCT) at 12-month intervals...
December 2017: Journal of Glaucoma
Ahmed Almazroa, Sami Alodhayb, Kaamran Raahemifar, Vasudevan Lakshminarayanan
Horizontal and vertical cup to disc ratios are the most crucial parameters used clinically to detect glaucoma or monitor its progress and are manually evaluated from retinal fundus images of the optic nerve head. Due to the rarity of the glaucoma experts as well as the increasing in glaucoma's population, an automatically calculated horizontal and vertical cup to disc ratios (HCDR and VCDR, resp.) can be useful for glaucoma screening. We report on two algorithms to calculate the HCDR and VCDR. In the algorithms, level set and inpainting techniques were developed for segmenting the disc, while thresholding using Type-II fuzzy approach was developed for segmenting the cup...
2017: International Journal of Biomedical Imaging
Alina Oltean, Larry A Taber
During the initial stages of eye development, optic vesicles grow laterally outward from both sides of the forebrain and come into contact with the surrounding surface ectoderm (SE). Within the region of contact, these layers then thicken locally to create placodes and invaginate to form the optic cup (primitive retina) and lens vesicle (LV), respectively. This paper examines the biophysical mechanisms involved in LV formation, which consists of three phases: (1) lens placode formation; (2) invagination to create the lens pit (LP); and (3) closure to form a complete ellipsoidally shaped LV...
September 15, 2017: Physical Biology
NaiLi Wei, ZiFang Quan, Hailiang Tang, JianHong Zhu
In recent years, scientists have made great achievements in understanding the development of human brain and elucidating critical elements of stepwise spatiotemporal control strategies in neural stem cell specification lineage, which facilitates successful induction of neural organoid in vitro including the cerebral cortex, cerebellar, neural tube, hippocampus cortex, pituitary, and optic cup. Besides, emerging researches on neural organogenesis promote the application of 3D organoid system transplantation in treating central nervous system (CNS) diseases...
2017: Stem Cells International
Ales Cvekl, Xin Zhang
Ocular lens development represents an advantageous system in which to study regulatory mechanisms governing cell fate decisions, extracellular signaling, cell and tissue organization, and the underlying gene regulatory networks. Spatiotemporally regulated domains of BMP, FGF, and other signaling molecules in late gastrula-early neurula stage embryos generate the border region between the neural plate and non-neural ectoderm from which multiple cell types, including lens progenitor cells, emerge and undergo initial tissue formation...
October 2017: Trends in Genetics: TIG
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