• The uveoscleral, or uveovortex, pathway, which accounts for perhaps 10% of the aqueous drainage in the healthy aged human eye, can become a major accessory route for aqueous drainage after pharmacologic treatment. (nih.gov)
  • The conventional aqueous outflow pathway is subjected to a rate-dependent IOP load-boundary with large fluctuations. (lu.se)
  • Statement of significance: While the human conventional aqueous outflow pathway is subjected to a large-deformation and time-dependent IOP load-boundary, we are not aware of any studies that have calculated the hyperviscoelastic mechanical properties of the outflow tissues with embedded viscoelastic collagen fibrils. (lu.se)
  • The proposed experimental-computational workflow may significantly contribute to understanding of the effects of different drugs on the biomechanics of the conventional aqueous outflow pathway. (lu.se)
  • Based on knowledge regarding the role of protein kinase C (PKC) in vascular biology, we sought to understand the contribution of the PKC pathway towards outflow function by studying the modulation of contractile and morphological characteristics of TM and SC cells. (duke.edu)
  • It can also happen if aqueous flow is restricted earlier along its pathway or if the eye produces too much aqueous humor. (allaboutvision.com)
  • One way to differentiate among MIGS devices is according to where in the aqueous drainage pathway it has an effect. (crstoday.com)
  • 2 Moreover, these anatomic structures function within the conventional outflow pathway. (crstoday.com)
  • Mahmoud A. Khaimi, MD, demonstrates ab interno canaloplasty to restore the aqueous outflow pathway. (crstoday.com)
  • He moved next to a discussion of devices that target the uveoscleral aqueous outflow pathway. (ophthalmologytimes.com)
  • The CyPass Micro-Stent (Transcend Medical) and the iStent supra (Glaukos) are both designed to release aqueous through the uveoscleral outflow pathway. (ophthalmologytimes.com)
  • 98% of the aqueous humor exits the eye via either the trabecular meshwork and the Schlemm canal (the major pathway, particularly in older people) or the ciliary body face and choroidal vasculature (also called the uveoscleral pathway and can make up to 50% of outflow in people younger than 30). (msdmanuals.com)
  • This allows increased outflow of aqueous humor by mechanically opening the iridocorneal angle. (wedgewoodpharmacy.com)
  • Histologic, experimental, and theoretical studies of the aqueous outflow pathways point toward the juxtacanalicular region and inner wall of Schlemm's canal as the likely site of aqueous outflow resistance in the normal eye. (nih.gov)
  • Cell atlas of aqueous humor outflow pathways in eyes of humans and four model species provides insight into glaucoma pathogenesis. (bvsalud.org)
  • Typically, glaucoma patients experience poor drainage of aqueous humor (AH) through the natural outflow pathways (i.e., trabecular meshwork and Schlemm's canal) 11 . (nature.com)
  • Aqueous humor is produced in the ciliary processes at 2-3 μL/min diurnally (and approximately 50% less nocturnally) and drains through the trabecular and uveoscleral pathways. (aao.org)
  • Tumor-induced glaucoma may be produced by obstruction of outflow pathways by pigment cells (pigment dispersion syndrome), melanin-laden macrophages (melanomalytic glaucoma), or tumor cells. (medscape.com)
  • These outflow pathways are not simply a mechanical filter and drain but instead involve active physiologic processes. (msdmanuals.com)
  • Emerging trabecular outflow drugs. (nih.gov)
  • it produces aqueous humor, facilitates trabecular outflow, intervenes in alteration of the shape of the crystalline lens during accommodation, and secretes hyaluronic acid into the vitreous. (medscape.com)
  • Glaucoma may be related to drainage of aqueous humor from the eye. (wikipedia.org)
  • The main determinant of IOP is the equilibrium between production and drainage of aqueous humor , with compromised drainage generally viewed as the primary contributor to dangerous IOP elevations. (bvsalud.org)
  • Too much aqueous production or obstruction of its outflow causes a rise in IOP that can lead to glaucoma. (allaboutvision.com)
  • In Primary Open Angle Glaucoma, the most prevalent form of glaucoma, an obstruction of the outflow system leads to an abnormal increase in eye pressure, and with time, to blindness. (yale.edu)
  • IOP elevation in human glaucoma results from an obstruction of the outflow system leading to an abnormal increase in eye pressure, death of retinal ganglion cells and loss of vision. (yale.edu)
  • or left outflow obstruction. (who.int)
  • At least 50% of the aqueous outflow resistance in the normal eye and the bulk of the pathologically increased resistance in the glaucomatous eye resides in the trabecular meshwork and the inner wall of Schlemm's canal. (nih.gov)
  • Surgeries that unroof Schlemm's canal or expand the canal, such as viscocanalostomy, probably cause inadvertent ruptures of the inner wall and juxtacanalicular tissue, thus relieving the abnormal outflow resistance of glaucoma. (nih.gov)
  • The aqueous humor actively interacts with the trabecular meshwork (TM), juxtacanalicular tissue (JCT), and Schlemm's canal (SC) through a dynamic fluid-structure interaction (FSI) coupling. (lu.se)
  • Although the TM and Schlemm's canal (SC) comprise the major route for aqueous humor outflow, little is known about the potential signaling mechanisms involved in the regulation of aqueous outflow. (duke.edu)
  • A mathematical model of Schlemm's canal is developed to simulate collapse of the canal and its effect on resistance to flow through the aqueous outflow network. (northwestern.edu)
  • Based on comparisons between the model and results in the literature, The following tentative conclusions are reached: (1) Most of the resistance in the aqueous outflow network occurs in the inner wall of Schlemm's canal. (northwestern.edu)
  • Johnson, MC & Kamm, RD 1983, ' The role of Schlemm's canal in aqueous outflow from the human eye ', Investigative Ophthalmology and Visual Science , vol. 24, no. 3, pp. 320-325. (northwestern.edu)
  • Schlemm's canal collects aqueous humor from the anterior chamber. (wikipedia.org)
  • Its inner face contacts the Schlemm's canal, and its external face contacts the aqueous humor. (aao.org)
  • 3.2 Corneoscleral meshwork, from the scleral spur to the scleral sulcus, with smaller oval holes as they approach the Schlemm's canal, offering slightly more resistance to the aqueous humor. (aao.org)
  • The end of the rivet inserts into Schlemm's canal, with the head in the anterior chamber allowing aqueous fluid to pass through the lumen in the middle of the device. (ophthalmologytimes.com)
  • Most new surgical innovations have been designed according to natural physiology by routing aqueous as nature intended, through the Schlemm's canal. (intechopen.com)
  • they include outflow facility, aqueous humor production rate, episcleral venous pressure, and uveoscleral outflow rate. (aao.org)
  • 1 Possible mechanisms for these changes include increased aqueous outflow, decreased episcleral venous pressure, decreased scleral rigidity, and generalized acidosis during pregnancy. (aao.org)
  • Clarifying the mechanisms and regulation of aqueous humor formation can lead to novel strategies for lowering IOP, the only intervention known to retard the onset and progression of blindness in glaucoma. (yale.edu)
  • A balance between the rates of secretion and drainage of the aqueous humor determines the level of IOP. (yale.edu)
  • IOP is determined by the balance of aqueous secretion and drainage. (msdmanuals.com)
  • TIMOPTIC Ophthalmic Solution is supplied as a sterile, isotonic, buffered, aqueous solution of timolol maleate in two dosage strengths: Each mL of TIMOPTIC 0.25% contains 2.5 mg of timolol (3.4 mg of timolol maleate). (nih.gov)
  • The hyperviscoelastic mechanical properties of the outflow tissues' extracellular matrix with embedded viscoelastic collagen fibrils were calculated using an inverse FE-optimization method. (lu.se)
  • Introduction The outflow of aqueous humor across the trabecular meshwork (TM) is usually regulated by among other factors actomyosin contraction of the resident TM cells and altered extracellular matrix (ECM) [1-3]. (cell-signaling-pathways.com)
  • The data obtained from this study demonstrate that Noladin ether increases aqueous humor outflow facility and that its effect is mediated through the CB1 cannabinoid receptor. (arvojournals.org)
  • Intriguingly, both PDBU and GF109203X caused increases in aqueous outflow facility in the perfusion model. (duke.edu)
  • Selective alpha 2-receptor that reduces aqueous humor formation and increases uveoscleral outflow. (medscape.com)
  • An understanding of aqueous humor dynamics is essential for the evaluation and management of glaucoma. (aao.org)
  • Based on the newer insights in aqueous outflow, this text offers a rational approach to the medical and surgical management of glaucoma. (intechopen.com)
  • Ex vivo perfusion studies have exhibited that brokers that increase the actomyosin contraction of TM cells decrease aqueous humor outflow and vice versa [4-6]. (cell-signaling-pathways.com)
  • Glaucoma drops are formulated to decrease aqueous production, increase aqueous outflow or do both of these jobs at the same time. (oliviasvision.org)
  • Gonioscopy-assisted transluminal trabeculotomy (GATT) is a conjunctiva-sparing approach to decrease IOP that strives to enhance the natural physiological outflow from the eye. (aao.org)
  • Glaucoma treatments include various topical and oral medications, cilioablative or trabecular meshwork laser procedures, and various surgical techniques designed to improve trabecular meshwork outflow, increase suprachoroidal drainage, or divert aqueous to the subconjunctival space. (medscape.com)
  • Goniodysgenesis, narrowing or closure of the iridocorneal angle through which the aqueous humor drains, may be detectable through gonioscopy. (wisdompanel.com)
  • After the outflow facility had been stabilized, Noladin ether was administrated to the perfusion medium and the outflow facility was observed for 5 hours. (arvojournals.org)
  • We investigated the involvement of PKC in regulation of myosin light chain (MLC) phosphorylation, formation of actin stress fibers and integrin-ECM adhesions (focal adhesions) in human TM and SC cells and correlated these changes with aqueous outflow facility measured in an enucleated porcine whole eye perfusion model. (duke.edu)
  • This requires parallel studies on genes that are important for the function of the retina, the optic nerve and aqueous humor outflow system in the normal eye. (nih.gov)
  • 3.1 The Uveal meshwork, adjacent to the aqueous humor, is formed by trabeculae with large holes, from 25 to 75 µm [16] . (aao.org)
  • Decreases IOP by increasing outflow of aqueous humor. (medscape.com)
  • The ciliary epithelium, a bilayer of secretory neuroepithelial cells, is the site of synthesis of aqueous humor (inflow system), and it regulates its secretion by the coordinated action of a complex transport system that involves ion channels and active transporters. (yale.edu)
  • The ciliary epithelium, a bilayer of secretory neuroepithelial cells, is the site of synthesis of aqueous humor (inflow system), and regulates its secretion by the coordinated action of a complex transport system involving ion channels and active ion secretion, from the stromal to the aqueous-humor surface, followed by osmotic water movement. (yale.edu)
  • However, in some studies a slight increase in outflow facility was also observed. (nih.gov)
  • Parasympathomimetic drugs also increase aqueous humor protein and may cause vasodilation of the conjunctiva. (wedgewoodpharmacy.com)
  • Sympathomimetic drugs such as dipivefrin also increase the outflow of aqueous humor but by a different mechanism than the parasympathomimetic drugs such as demecarium bromide. (wedgewoodpharmacy.com)
  • They also may increase inflammation by enhancing breakdown of the blood-aqueous barrier. (medscape.com)
  • The terms open angle and angle closure describe the basic structural issue within the eye that is disrupting aqueous flow. (allaboutvision.com)
  • In angle-closure forms, the aqueous can't leave the eye because the iris is blocking the drainage angle. (allaboutvision.com)
  • These observations led to the hypothesis that this contraction of TM cells regulates the outflow facility possibly through the reorganization of the TM through altered cell-ECM interactions. (cell-signaling-pathways.com)
  • Scholars@Duke publication: The role of protein kinase C in modulation of aqueous humor outflow facility. (duke.edu)
  • The resultant deformation/strain in the outflow tissues was calculated using the FSI method, and compared to the digital volume correlation (DVC) data. (lu.se)
  • This necessitates addressing the biomechanics of the outflow tissues using hyperviscoelastic material-model. (lu.se)
  • Emerging evidence in the glaucoma literature has expanded the understanding of aqueous flow dynamics. (crstoday.com)
  • Collectively, an evolved understanding of aqueous flow dynamics demonstrate that the entire system is complex, and each component has a function in physiologic flow. (crstoday.com)
  • The objective of this study was to investigate the effect of Noladin ether on aqueous humor outflow facility and to test whether its action is CB1 receptor-mediated. (arvojournals.org)
  • Noladin ether produced a significant enhancement of outflow facility. (arvojournals.org)
  • These results suggest that PKC might play an important role in modulation of aqueous outflow facility by regulating MLC phosphorylation and thereby, the morphological and cytoskeletal characteristics of TM and SC cells. (duke.edu)
  • Purpose The outflow facility for aqueous humor across the trabecular meshwork (TM) is enhanced by agents that oppose the actomyosin contraction of GSK690693 its resident cells. (cell-signaling-pathways.com)
  • In addition, IOP and outflow facility are normal between episodes. (medscape.com)