The document summarizes various drug delivery systems that have been developed for the treatment of uveitis. It describes both non-biodegradable and biodegradable intraocular implants such as Retisert, Iluvien, Surodex, Ozurdex, and Vitrasert that provide sustained release of corticosteroids over months. Emerging methods discussed include iontophoresis, drug-eluting contact lenses, and nanoparticles to help penetrate tissue and provide more controlled drug release. Overall, the development of new drug delivery systems aims to reduce systemic side effects of long-term corticosteroids while maintaining therapeutic drug levels in the eye.
Topical dorzolamide for macular edema in the early phase after vitrectomy and...Avaleks-Kiev
Background: The purpose of this study was to evaluate prospectively the efficacy of a topical carbonic anhydrase inhibitor in macular edema after vitrectomy.
Цель: оценка перспективы использования топического ингибитора карбоангидразы для профилактики развития макулярного отека после витрэктомии.
http://ophthalmolog.kiev.ua/
This meta-analysis evaluated the effectiveness of bevacizumab (Avastin) treatment on corneal neovascularization (NV) based on 7 clinical human studies and 18 animal studies. The results showed that bevacizumab significantly reduced the area of corneal NV in both human and animal studies. Specifically, bevacizumab reduced the neovascularized area in human studies by an average of 36% overall, with 32% reduction for subconjunctival injections and 48% for topical treatment. Bevacizumab also improved best-corrected visual acuity in human studies. In animal studies, bevacizumab significantly reduced the area of corneal NV compared to controls.
This study evaluated the use of multiple trabecular micro-bypass stents combined with cataract surgery in 53 eyes of patients with open-angle glaucoma and cataract. The study found that using 2 or 3 micro-bypass stents led to a mean postoperative intraocular pressure of 14.3 mm Hg, significantly lower than the preoperative pressure of 18.0 mm Hg. Patients were also able to achieve their target pressure control with significantly fewer glaucoma medications, with a 74% reduction in the mean number of medications used from 2.7 preoperatively to 0.7 at the 1-year follow up. Patients who received 3 stents were on significantly fewer medications than those who received
This study examined the 1-year results of treating myopic choroidal neovascularization (CNV) with intravitreal bevacizumab injections. Twenty-nine patients received three initial monthly injections, with additional injections for persistent or recurrent CNV. At 1 year, visual acuity improved on average by 2.4 lines from baseline. Twenty-one patients (72.4%) gained over 2 lines of vision. Optical coherence tomography showed a reduction in central foveal thickness following treatment. The study demonstrates the long-term effectiveness of intravitreal bevacizumab for myopic CNV.
EMERGING APPROACHES TO COMBINATION THERAPIES IN AMD & DME - OptheaHealthegy
Panel Discussion by Opthea at OIS@ASRS 2016.
Participant:
Megan Baldwin, PhD, CEO & Managing Director - Opthea
Powered by:
Healthegy
For more ophthalmology innovation
Visit us at www.ois.net
RETINA COMPANY SHOWCASE - Catalyst BiosciencesHealthegy
Panel Discussion by Catalyst Biosciences at OIS@ASRS 2016.
Participant:
Edwin Madison, PhD, Chief Scientific Officer - Catalyst Biosciences
Powered by:
Healthegy
For more ophthalmology innovation
Visit us at www.ois.net
NW2007 Intravitreal Avastin Injection for Diabetic RetinopathyNawat Watanachai
Intravitreal corticosteroids and anti-VEGF agents are effective treatments for diabetic retinopathy complications. Corticosteroids decrease vascular permeability and inflammation while anti-VEGF agents target VEGF to inhibit neovascularization. Studies show intravitreal triamcinolone, Avastin, Lucentis, Macugen, and Pegaptanib improve vision and reduce macular edema in diabetic macular edema. Avastin and Macugen also help regress neovascularization as adjunctive treatment for proliferative diabetic retinopathy. Pre-operative anti-VEGF injections enhance vitrectomy outcomes in eyes with active neovascularization or vitreous hemorrhage by reducing intraoperative bleeding. However
Topical dorzolamide for macular edema in the early phase after vitrectomy and...Avaleks-Kiev
Background: The purpose of this study was to evaluate prospectively the efficacy of a topical carbonic anhydrase inhibitor in macular edema after vitrectomy.
Цель: оценка перспективы использования топического ингибитора карбоангидразы для профилактики развития макулярного отека после витрэктомии.
http://ophthalmolog.kiev.ua/
This meta-analysis evaluated the effectiveness of bevacizumab (Avastin) treatment on corneal neovascularization (NV) based on 7 clinical human studies and 18 animal studies. The results showed that bevacizumab significantly reduced the area of corneal NV in both human and animal studies. Specifically, bevacizumab reduced the neovascularized area in human studies by an average of 36% overall, with 32% reduction for subconjunctival injections and 48% for topical treatment. Bevacizumab also improved best-corrected visual acuity in human studies. In animal studies, bevacizumab significantly reduced the area of corneal NV compared to controls.
This study evaluated the use of multiple trabecular micro-bypass stents combined with cataract surgery in 53 eyes of patients with open-angle glaucoma and cataract. The study found that using 2 or 3 micro-bypass stents led to a mean postoperative intraocular pressure of 14.3 mm Hg, significantly lower than the preoperative pressure of 18.0 mm Hg. Patients were also able to achieve their target pressure control with significantly fewer glaucoma medications, with a 74% reduction in the mean number of medications used from 2.7 preoperatively to 0.7 at the 1-year follow up. Patients who received 3 stents were on significantly fewer medications than those who received
This study examined the 1-year results of treating myopic choroidal neovascularization (CNV) with intravitreal bevacizumab injections. Twenty-nine patients received three initial monthly injections, with additional injections for persistent or recurrent CNV. At 1 year, visual acuity improved on average by 2.4 lines from baseline. Twenty-one patients (72.4%) gained over 2 lines of vision. Optical coherence tomography showed a reduction in central foveal thickness following treatment. The study demonstrates the long-term effectiveness of intravitreal bevacizumab for myopic CNV.
EMERGING APPROACHES TO COMBINATION THERAPIES IN AMD & DME - OptheaHealthegy
Panel Discussion by Opthea at OIS@ASRS 2016.
Participant:
Megan Baldwin, PhD, CEO & Managing Director - Opthea
Powered by:
Healthegy
For more ophthalmology innovation
Visit us at www.ois.net
RETINA COMPANY SHOWCASE - Catalyst BiosciencesHealthegy
Panel Discussion by Catalyst Biosciences at OIS@ASRS 2016.
Participant:
Edwin Madison, PhD, Chief Scientific Officer - Catalyst Biosciences
Powered by:
Healthegy
For more ophthalmology innovation
Visit us at www.ois.net
NW2007 Intravitreal Avastin Injection for Diabetic RetinopathyNawat Watanachai
Intravitreal corticosteroids and anti-VEGF agents are effective treatments for diabetic retinopathy complications. Corticosteroids decrease vascular permeability and inflammation while anti-VEGF agents target VEGF to inhibit neovascularization. Studies show intravitreal triamcinolone, Avastin, Lucentis, Macugen, and Pegaptanib improve vision and reduce macular edema in diabetic macular edema. Avastin and Macugen also help regress neovascularization as adjunctive treatment for proliferative diabetic retinopathy. Pre-operative anti-VEGF injections enhance vitrectomy outcomes in eyes with active neovascularization or vitreous hemorrhage by reducing intraoperative bleeding. However
The document discusses a 3D motion sensor and barometric pressure sensor device that tracks fitness data through Bluetooth communication. It works by establishing a connection between the tracker and base, exchanging identification and operation codes, and transmitting fitness data to a server. Potential threats include lack of encryption, man-in-the-middle attacks, and Bluetooth attacks. While data leaks are a risk, the technology could also benefit society by motivating health and enabling doctors to track patients.
Este documento proporciona información sobre 120 barcos participantes en la Ruta de la Sal 2012. Incluye detalles como el número de identificación, país, nombre, patrón y modelo de cada barco. La información se presenta en una tabla con columnas para cada uno de estos detalles y filas para cada embarcación participante.
Rahul Srivastava has over 4.6 years of experience in quality control, metallurgical operations, and research and development. He is currently an Assistant Manager at POSCO India Pvt. Ltd., where he oversees quality control and provides technical support. Previously, he held roles at Mittal Corp Ltd. and VBC Ferro Alloys Ind. Ltd. Rahul has expertise in steelmaking processes, quality standards, and metallurgical testing. He aims to take on challenging assignments to further enhance his knowledge and support organizational growth.
This document discusses lessons learned from superstar companies. It identifies 9 common characteristics of highly successful companies: 1) obsession with talent, 2) investing in core skills, 3) balancing long and short-term goals, 4) setting extravagant goals, 5) attention to detail, 6) regularly reassessing investments, 7) balancing global scale with local roots, 8) disrupting their own businesses before others can, and 9) transforming themselves regularly to adapt to changes. Examples are provided for each characteristic from companies like GE, Amazon, BMW, Google, Apple, and others.
Patricia Durán Ospina es microbióloga y directora del Centro de Investigaciones de la Fundación Universitaria del Área Andina en Pereira. Tuvo cargos directivos en Novartis y fue cofundadora del Grupo Salud Visual, además de ser miembro de juntas directivas de asociaciones de simulación clínica y fisiología. El documento proporciona lineamientos sobre el marco jurídico en epidemiología incluyendo legislación internacional, nacional y protocolos regionales de la OMS. También presenta recursos online para investig
The document discusses food chains and the flow of energy through ecosystems. It explains that plants are producers that use photosynthesis to make their own food from sunlight. Animals are consumers that get energy by eating producers or other consumers. There are herbivores that eat plants, omnivores that eat plants and animals, and carnivores that eat other animals. Energy moves from producers to consumers in a food chain, and decomposers like fungi and bacteria break down dead organisms, recycling nutrients back into the soil for producers.
This document is the user guide for Deep Freeze Standard. It provides information about installing, configuring, and using Deep Freeze Standard to protect computers by making their configurations indestructible and reverting them to a known good state after each reboot. The guide covers topics such as system requirements, attended and silent installation and uninstallation methods, installing over existing versions of Deep Freeze, and using features like the status tab and password tab.
Este documento proporciona una lista provisional de embarcaciones inscritas para una regata. Incluye el número de vela, nombre del barco, nombre del patrón, marca y modelo de la embarcación, asociación a la que pertenece y puntaje de velocidad potencial sobre la manga. Hay más de 300 embarcaciones de España y otros países listadas con sus respectivos detalles.
Este documento proporciona una lista de inscritos para la Ruta de la Sal de 2012, incluyendo 57 embarcaciones de varios países. Cada entrada incluye el número de embarcación, país, nombre, capitán, marca y modelo del barco, y club al que pertenece.
Este documento proporciona una lista de 72 embarcaciones participantes en la Ruta de la Sal 2013, con su número de vela, nombre, patrón, marca y modelo de barco, asociación a la que pertenecen y su puntuación SPM_M. La información incluye detalles como el país de origen, nombre del barco, patrón y características técnicas de cada embarcación.
This document provides contact information for the NidoKidoS Group and ways to receive more information or participate in discussions on their website. The group is sharing a presentation file and reserves all rights to the contents.
Este documento presenta una lista de inscritos para la regata "La Ruta de la Sal - Trofeo Pepe Ferres". Incluye 77 embarcaciones divididas en varias categorías (I, A1, A2, B, C, D, etc.) con su número, nombre, patrón, marca y modelo del barco, país y club de pertenencia.
This document discusses personal branding and using social media to communicate one's personal brand. It provides an overview of personal branding and how individuals can use platforms like LinkedIn, Twitter, Facebook and blogs to help others learn about their qualities and expertise. The document also discusses how social media can help establish a personal brand and the importance of using current platforms to reach audiences. Millennials and future generations expect learning and relationships to include an online component through social media.
This document presents a case study on using hydrogel drug delivery systems to treat macular degeneration. It discusses using anti-VEGF drugs bevacizumab and ranibizumab, delivered via hydrogel injections into the eye. The document models drug diffusion through the hydrogel and into eye tissue, comparing diffusion rates and profiles of the two drugs. It also evaluates using intravenous bevacizumab to treat cancer and models its pharmacokinetics in the body.
This document summarizes minimally invasive glaucoma surgery (MIGS) procedures. MIGS offers more modest intraocular pressure (IOP) lowering than traditional glaucoma surgery, but with a safer risk profile. The document describes various MIGS procedures including the iStent, Hydrus, CyPass, and XEN gel stent. It provides details on the mechanism of action, surgical technique, efficacy and safety data from clinical studies for each procedure. MIGS provides an alternative treatment option for glaucoma patients to lower IOP and reliance on eye drops without the risks of more invasive surgeries.
The document discusses a 3D motion sensor and barometric pressure sensor device that tracks fitness data through Bluetooth communication. It works by establishing a connection between the tracker and base, exchanging identification and operation codes, and transmitting fitness data to a server. Potential threats include lack of encryption, man-in-the-middle attacks, and Bluetooth attacks. While data leaks are a risk, the technology could also benefit society by motivating health and enabling doctors to track patients.
Este documento proporciona información sobre 120 barcos participantes en la Ruta de la Sal 2012. Incluye detalles como el número de identificación, país, nombre, patrón y modelo de cada barco. La información se presenta en una tabla con columnas para cada uno de estos detalles y filas para cada embarcación participante.
Rahul Srivastava has over 4.6 years of experience in quality control, metallurgical operations, and research and development. He is currently an Assistant Manager at POSCO India Pvt. Ltd., where he oversees quality control and provides technical support. Previously, he held roles at Mittal Corp Ltd. and VBC Ferro Alloys Ind. Ltd. Rahul has expertise in steelmaking processes, quality standards, and metallurgical testing. He aims to take on challenging assignments to further enhance his knowledge and support organizational growth.
This document discusses lessons learned from superstar companies. It identifies 9 common characteristics of highly successful companies: 1) obsession with talent, 2) investing in core skills, 3) balancing long and short-term goals, 4) setting extravagant goals, 5) attention to detail, 6) regularly reassessing investments, 7) balancing global scale with local roots, 8) disrupting their own businesses before others can, and 9) transforming themselves regularly to adapt to changes. Examples are provided for each characteristic from companies like GE, Amazon, BMW, Google, Apple, and others.
Patricia Durán Ospina es microbióloga y directora del Centro de Investigaciones de la Fundación Universitaria del Área Andina en Pereira. Tuvo cargos directivos en Novartis y fue cofundadora del Grupo Salud Visual, además de ser miembro de juntas directivas de asociaciones de simulación clínica y fisiología. El documento proporciona lineamientos sobre el marco jurídico en epidemiología incluyendo legislación internacional, nacional y protocolos regionales de la OMS. También presenta recursos online para investig
The document discusses food chains and the flow of energy through ecosystems. It explains that plants are producers that use photosynthesis to make their own food from sunlight. Animals are consumers that get energy by eating producers or other consumers. There are herbivores that eat plants, omnivores that eat plants and animals, and carnivores that eat other animals. Energy moves from producers to consumers in a food chain, and decomposers like fungi and bacteria break down dead organisms, recycling nutrients back into the soil for producers.
This document is the user guide for Deep Freeze Standard. It provides information about installing, configuring, and using Deep Freeze Standard to protect computers by making their configurations indestructible and reverting them to a known good state after each reboot. The guide covers topics such as system requirements, attended and silent installation and uninstallation methods, installing over existing versions of Deep Freeze, and using features like the status tab and password tab.
Este documento proporciona una lista provisional de embarcaciones inscritas para una regata. Incluye el número de vela, nombre del barco, nombre del patrón, marca y modelo de la embarcación, asociación a la que pertenece y puntaje de velocidad potencial sobre la manga. Hay más de 300 embarcaciones de España y otros países listadas con sus respectivos detalles.
Este documento proporciona una lista de inscritos para la Ruta de la Sal de 2012, incluyendo 57 embarcaciones de varios países. Cada entrada incluye el número de embarcación, país, nombre, capitán, marca y modelo del barco, y club al que pertenece.
Este documento proporciona una lista de 72 embarcaciones participantes en la Ruta de la Sal 2013, con su número de vela, nombre, patrón, marca y modelo de barco, asociación a la que pertenecen y su puntuación SPM_M. La información incluye detalles como el país de origen, nombre del barco, patrón y características técnicas de cada embarcación.
This document provides contact information for the NidoKidoS Group and ways to receive more information or participate in discussions on their website. The group is sharing a presentation file and reserves all rights to the contents.
Este documento presenta una lista de inscritos para la regata "La Ruta de la Sal - Trofeo Pepe Ferres". Incluye 77 embarcaciones divididas en varias categorías (I, A1, A2, B, C, D, etc.) con su número, nombre, patrón, marca y modelo del barco, país y club de pertenencia.
This document discusses personal branding and using social media to communicate one's personal brand. It provides an overview of personal branding and how individuals can use platforms like LinkedIn, Twitter, Facebook and blogs to help others learn about their qualities and expertise. The document also discusses how social media can help establish a personal brand and the importance of using current platforms to reach audiences. Millennials and future generations expect learning and relationships to include an online component through social media.
This document presents a case study on using hydrogel drug delivery systems to treat macular degeneration. It discusses using anti-VEGF drugs bevacizumab and ranibizumab, delivered via hydrogel injections into the eye. The document models drug diffusion through the hydrogel and into eye tissue, comparing diffusion rates and profiles of the two drugs. It also evaluates using intravenous bevacizumab to treat cancer and models its pharmacokinetics in the body.
This document summarizes minimally invasive glaucoma surgery (MIGS) procedures. MIGS offers more modest intraocular pressure (IOP) lowering than traditional glaucoma surgery, but with a safer risk profile. The document describes various MIGS procedures including the iStent, Hydrus, CyPass, and XEN gel stent. It provides details on the mechanism of action, surgical technique, efficacy and safety data from clinical studies for each procedure. MIGS provides an alternative treatment option for glaucoma patients to lower IOP and reliance on eye drops without the risks of more invasive surgeries.
Vascular endothelial growth factors promote neovascularization and break the blood-retinal barrier. Anti-vascular endothelial growth factor (anti-VEGF) therapies block VEGF's actions, decreasing abnormal new blood vessel formation and retinal leakage/swelling. This stabilizes vision and may improve it. Bevacizumab, ranibizumab, and aflibercept are examples of anti-VEGF drugs used intravitreally to treat wet age-related macular degeneration, diabetic retinopathy, retinal vein occlusion and other conditions. While effective, anti-VEGF therapies require frequent injections and monitoring for side effects like increased intraocular pressure.
Topical bevacizumab was used as an adjunct to conjunctival autograft surgery for 17 patients with primary pterygium. No patients experienced recurrence of the pterygium over the 2-year follow-up period. The topical regimen of bevacizumab, flurbiprofen, and artificial tears was well tolerated with minimal side effects. The authors conclude that topical bevacizumab may be a safe and effective alternative to prevent pterygium recurrence compared to other options like mitomycin C or radiation therapy that have greater risks of side effects. Larger controlled studies are still needed.
Pterygium Excision with Free Conjunctival Limbal Autograftiosrjce
IOSR Journal of Dental and Medical Sciences is one of the speciality Journal in Dental Science and Medical Science published by International Organization of Scientific Research (IOSR). The Journal publishes papers of the highest scientific merit and widest possible scope work in all areas related to medical and dental science. The Journal welcome review articles, leading medical and clinical research articles, technical notes, case reports and others.
1. Closed incisional negative pressure wound therapy (CI-NPWT) is a non-invasive wound closure device that applies localized negative pressure to closed surgical incisions to help with wound healing.
2. A study analyzed the biological effects of CI-NPWT on surgical sites healing by primary intention and found increased tissue perfusion, organized collagen production, and reduced rates of complications like surgical site infections, seromas, and hematomas.
3. Histological and electron microscopy analysis revealed that CI-NPWT increases microvascular density, induces organized collagen fiber formation, and activates fibroblasts through effects on cell junctions, organelles, and nuclear patterns at the microscopic level.
This study compared the efficacy of injectable collagenase versus partial fasciectomy in treating Dupuytren's contracture. 15 patients (33 rays) were divided into two groups: Group A underwent partial fasciectomy (26 rays) while Group B was treated with collagenase injections (7 rays). The collagenase treatment was found to be safe and effective, with contractures improving significantly and few complications. However, recurrence and failure rates were slightly higher compared to surgery. While collagenase injection is a good alternative to surgery, its higher cost should be considered, especially in developing countries.
OCT Angiography provides a new non-invasive method to visualize retinal vessels without intravenous dye. It produces higher resolution images than traditional OCT, detecting even trace amounts of exudation. However, questions remain about how to interpret and clinically apply the additional information it provides. While it can detect exudation earlier and show incomplete resolution with treatment, the implications of persistent or recurrent exudation seen on OCT Angiography are still unclear. This specific patient has barely perceptible exudation on routine OCT but cysts and fluid are visible on OCT Angiography. It is uncertain whether treatment is required given her good vision and lack of symptoms.
This document provides an update on several clinical trials testing new treatments for age-related macular degeneration (AMD). It summarizes trials of anti-PDGF aptamers, visual cycle modulators, anti-inflammatory agents, radiation therapy, stem cell therapy, RPE protection agents, and drugs to increase choroidal blood flow. It also discusses long-term follow up data from previous anti-VEGF trials showing a progressive loss of vision over 7 years due to macular atrophy and increased lesion size, despite maintenance therapy.
Muhammad Ali was a heavyweight boxing champion with an impressive 56-win record. Endoscopic injection techniques for treating vesicoureteral reflux (VUR) have improved since first being used in the 1980s, with success rates now over 85% for most cases. The standard techniques are STING (subureteric injection) and double HIT (hydrodistension intraureteric submucosal injections), with the latter achieving high success rates across all VUR grades. Complications are generally minor but can include new contralateral VUR or temporary obstruction.
A Comparison of The Lateral Tarsal Strip with Everting Sutures and The Quic...Meironi Waimir
Entropion is Inversion or rotation of the margo palpebra towards the eyeball.
Characterized by : Ocular discomfort, epiphora, secondary corneal thinning, vascularization and scarring as well as microbial keratitis and corneal perforation.
Capsule endoscopy_ A new dimension of endoscopy Final.pptxYasir Arafat
Capsule endoscopy is a modern diagnostic procedure that has revolutionized the field of gastroenterology. It involves swallowing a small capsule containing a camera that captures images of the digestive tract as it passes through the body. These images are then transmitted to a recording device, allowing physicians to visualize the entire gastrointestinal tract from the oesophagus to the colon.
Ocular drug delivery systems are designed to administer drugs onto or inside the eye. Conventional systems include eye drops, emulsions, suspensions, and ointments. However, only a small portion of the drug reaches the eye's interior using these methods. Novel nanotechnology-based systems like micelles, nanoparticles, liposomes, and dendrimers can more effectively target internal ocular tissues and increase drug residence in the eye. These novel systems may help improve treatment of diseases affecting the eye's anterior and posterior segments.
This document discusses stress urinary incontinence (SUI) and various treatment options. It begins by outlining some myths about SUI, noting that it is not simply a natural part of aging and can be treated. Conservative management options for SUI are discussed such as lifestyle changes and pelvic floor exercises. Surgical options for urodynamic stress incontinence (USI) are then summarized, including traditional approaches like Burch colposuspension as well as modern mid-urethral sling (MUS) procedures. Complications, outcomes, and long-term results are compared for different surgical techniques. Guidance from regulatory bodies on the appropriate use of MUS is also presented.
This document summarizes a study on the use of suprachoroidal buckling to treat rhegmatogenous retinal detachments caused by peripheral retinal breaks. 41 eyes underwent suprachoroidal buckling using Healon5 as a filler material injected through a 23-gauge cannula. Mean best corrected visual acuity improved from 20/1,100 to 20/42, and the single surgery reattachment rate was 92.7%. No major complications occurred. The technique allows creation of a circumferential buckle to support the retina. Suprachoroidal buckling avoids complications of episcleral buckling and accurately positions the buckle at the break site.
Treatment of Diabetic Macular Edema with Aflibercept and Micropulse Laser (DA...haha haha
This clinical trial investigated the safety and efficacy of combining intravitreal aflibercept injections with micropulse laser treatment for diabetic macular edema. Thirty patients were randomized to receive either injections with sham laser (Group 1) or injections with micropulse laser (Group 2). Both groups showed improvements in visual acuity and macular thickness after 48 weeks, with no significant differences between groups. While micropulse laser did not reduce the number of injections needed or further improve outcomes, it also did not cause any adverse effects when combined with anti-VEGF therapy.
Similar to Evolving trend of drug delivery system (20)
Treatment of Diabetic Macular Edema with Aflibercept and Micropulse Laser (DA...
Evolving trend of drug delivery system
1. www. dosonline.org l 67
Uvea
www. dosonline.org l 67
Uvea(YROXWLRQ
Pranita Sahay
MBBS
EvolvingTrend of Drug
Delivery System in Uveitis
Pranita Sahay MBBS, Devesh Kumawat MBBS,
Koushik Tripathy MD, DNB, Vijay Kumar Sharma MS
Dr. Rajendra Prasad Centre for Ophthalmic Sciences,
All India Institute of Medical Sciences, New Delhi
Uveitis is an umbrella term that includes any
KPƀCOOCVQT[ RTQEGUU VJCV RTKOCTKN[ CHHGEVU VJG WXGCN
tissue. It may be anterior, intermediate, posterior or
panuveitis. Intermediate, posterior uveitis, and panuveitis
are the most sight threatening types of uveitis. If no
infectious microbe is implicated in the disease process
then it is said to be idiopathic and treatment is aimed at
UWRRTGUUKPI VJG KPƀCOOCVQT[ RTQEGUU $[ HCT VJG OQUV
EQOOQP ENCUU QH FTWI VQ SWGPEJ VJG KPƀCOOCVQT[ ſTG
of uveitis is corticosteroids which can be administered in
various forms- oral, intravenous, topical drops, periocular
injection, intravitreal injection or intraocular implants.
Immunosuppressive agents and immunomodulators are the
other class of drugs used in the management of idiopathic
uveitis. Long term use of systemic corticosteroids and
immunomodulators have high risk of systemic adverse
effects and topical medication have poor penetration to the
posterior segment of eye. This has lead to a new era of
invention of sustained drug delivery system1
.
Retisert®
Introduced by Bausch and Lomb (Rochester, NY, USA)
in 1951, it is a non biodegradable, sustained release
KPVTCXKVTGCN KORNCPV QH ƀWEKPQNQPG CEGVQPKFG OI +V JCU
been FDA-approved (Food and Drug Administration, USA)
for chronic macular edema due to chronic non infectious
posterior uveitis2
. Retisert is about the size of a grain of
rice and consists of a tablet encased in a silicone elastomer
EWR EQPVCKPKPI C TGNGCUG QTKſEG CPF C 2QN[XKP[N CNEQJQN
(PVA) membrane positioned between the tablet and the
QTKſEG 6JG UKNKEQPG GNCUVQOGT EWR CUUGODN[ KU CVVCEJGF VQ
a PVA suture strut with silicone adhesive. It is implanted
into the vitreous cavity by par plana incision and then
suturing. The drug is delivered at initial rate of 0.6 μg/day,
FGETGCUKPI QXGT VJG ſTUV OQPVJ VQ C UVGCF[ UVCVG DGVYGGP
0.3 to 0.4 μg/day with no drug peaks and troughs, and it
lasts for approximately 1,000 days (30 months). During
clinical trials it has shown to decrease the recurrence of
episode from 54 % to 7% and 40% to 14% in two different
trials and also either stabilisation or an increase in visual
acuity in 80% patients was noted. The common ocular
adverse effects with Retisert are raised intraocular pressure
and cataract. MUST trial (Multicenter Uveitis Steroid
6TGCVOGPV GXCNWCVKPI KVU GHſECE[ KP WXGKVKU XGTUWU U[UVGOKE
CPVKKPƀCOOCVQT[ VJGTCR[ UJQYGF VKOGU KPETGCUG KP
glaucoma and 3.3 times increased cataract surgery rate3
.
Rare but the most dreaded one being endophthalmitis.
Another major disadvantage with Retisert is that it can’t be
KORNCPVGF KP CP QHſEG RTQEGFWTG
(KIWTG
Iluvien®
Iluvien® (formerlyMedidurFA,AlimeraSciences,Alpharetta,
GA, USA) is a non biodegradable intravitreal implant of
ƀWEKPQNQPG CEGVQPKFG zI +V EQPUKUVU QH C E[NKPFTKECN
polyimide tube, 3.5mm in length and 0.37mm in diameter.
Unlike Retisert however, Iluvien® is injected into the eye
CU CP QHſEG DCUGF RTQEGFWTG WUKPI C RTQRTKGVCT[ KPUGTVGT
with a 25-gauge needle, which allows a self sealing wound.
Figure 1: Retisert
2. 68 l DOS Times - Vol. 20, No. 3 September, 2014
Evolution: Evolving Trend of Drug Delivery System in Uveitis
The method of administration is similar to an intravitreal
KPLGEVKQP +V JCU DGGP J[RQVJGUKGF VJCV ƀWQEKPQNQPG
acetonide (FAc) inserts may cause fewer problems with
glaucoma than the surgically implanted device because
QH NQYGT KP XKVTQ TGNGCUG TCVGU QH ƀWQEKPQNQPG CEGVQPKFG
(0.2 and 0.5μg/day for at 24-36 months and 18 months
respectively) and also because of a more posterior location
in the eye, which may decrease exposure to the trabecular
meshwork in the anterior chamber while still delivering
CFGSWCVG NGXGNU QH ƀWQEKPQNQPG CEGVQPKFG VQ VJG TGVKPC
(Figure 2). Three year results of FAME study (Fluocinolone
Acetonide Implant Compared to Sham Injection in Patients
With Diabetic Macular Edema) showed that by 36 months,
80-90% patients in FAc groups required cataract surgery
versus 27.3% of phakic controls. Approximately 20%
of patients in FAc groups experienced an intraocular
pressure (IOP) more than 30 mm Hg at any point in the
study compared to 4.3% of sham control patients; 5-8%
of patients in FAc groups required IOP-lowering surgery
compared to 0.5% for controls, respectively4
.
Surodex®
Surodex produced by Allergan(Allergan, Irvine, CA,
USA) is a rod-shaped biodegradable matrix implant of
dexamethasone and poly lactideco- glycolide acid (PLGA)
with hydroxypropyl methylcellulose (HPMC). It is 1.0×0.5
mm in size and has a drug release rate of 60 μg over 7–10
days. It is implanted into the anterior chamber following
ECVCTCEV UWTIGT[ VQ EQPVTQN VJG RQUVQRGTCVKXG KPƀCOOCVKQP5
.
Ozurdex®
Ozurdex is produced by Allergan, Irvine, CA, USA is
also called Posurdex during trials. It is a biodegradable
intravitreal implant of dexamethasone 0.7 mg. The
Novadur™ drug delivery system containing poly (D, L-
lactide-co-glycolide) without preservative, degrades slowly
to lactic acid and glycolic acid. It has a preloaded single-
use specially designed applicator to facilitate the injection
of a rod-shaped implant directly into the vitreous cavity.
It is delivered via surgical sclerotomy or 22-gauge needle-
injector system. Its effect lasts for 6 months. Its adverse
effect being raised intraocular pressure which peaks at
around 60 days. Patients in whom the posterior capsule
of the lens is absent or has a tear are at risk of implant
migration into the anterior chamber. It is currently FDA
approved for central and branch retinal vein occlusion,
non infectious uveitis affecting the posterior segment and
diabetic macular oedema. HURON study is evaluating its
role in macular edema in posterior Uveitis (Figure 3).
Vitrasert
It is produced by Bausch and Lomb (Rochester, NY,
75# CPF KU VJG ſTUV KORNCPVCDNG ICPEKENQXKT FGNKXGT[
device approved by the FDA in 1996 for treatment of
cytomegalovirus (CMV) retinitis. Human viruses sensitive
to ganciclovir include cytomegalovirus (CMV), herpes
Figure 2: Iluvein
Figure 3: 2]XUGH[
3. www. dosonline.org l 69
Uvea
simplex virus-1 and -2 (HSV- 1, HSV- 2), Epstein - Barr
virus (EBV) and varicella zoster virus (VZV). The device is
composed of drug and polymeric coats of polyvinyl alcohol
(PVA) and ethylenevinyl acetate (EVA). PVA is a permeable
polymer that regulates the rate of ganciclovir release and
EVA is an impermeable polymer that limits the surface
area of the device through which the active agent can be
released. Each implant contains around 4.5 mg to 6.4mg of
ganciclovir. It releases the drug at mean rate of 1.4μg/day
and a mean vitreous concentration of 4.1μg/ml is achieved.
The device has shown to have no initial burst effect.
The commercially available device is relatively large;
it requires a 4–5mm sclerotomy at the pars plana for
implantation. It releases the drug for 5 to 8 months. Since
it is nonbiodegradable the drug-depleted device needs to
be removed during a second procedure in order to implant
another device if required (Figure 4).
Iontophoresis
It uses electrical current to facilitate delivery of medication
or ions into the tissue for therapeutic purposes based on the
physical principle that like charges repel each other. Eye
gate (Optis Group, Paris, France) and OcuPhor (IOMED,
Salt Lake City) are two ophthalmic iontophoresis systems
under investigation. EGP-437 (dexamethasone phosphate
formulated for iontophoresis) is being evaluated for non-
infectious anterior uveitis (Figure 5).
Contact Lens
Contact lenses can absorb drugs and release over a period
of time. Silicon-hydrogel contact lens loaded with vitamin E
has been shown to increase dexamethasone release period
from 1 day to 7 - 9 days6
.
Nanoparticles
They have the ability to penetrate tissue better, resulting
in more controlled release of drug over longer duration.
Figure 4: Vitrasert
Tamoxifen-loaded nanoparticles injected intravitreally
have been shown to be effective in treating experimental
autoimmune uveitis (EAU) models whereas non-
encapsulated tamoxifen had no effect7
. Betamethasone-
encapsulated particles have successfully treated
experimental autoimmune uveoretinitis models8
.
However further reasearch is warranted to discover newer
avenues of treating uveitis.
References
1. Nahid Haghjou, Masoud Soheilian, Mohammad Jafar Abdekhodaie,
Sustained Release Intraocular Drug Delivery Devices for Treatment
of Uveitis. Journal of ophthalmic and vision research 2011;4: 317-
29.
2. Jaffe GJ, Martin D, Callanan D. Fluocinolone acetonide implant
(Retisert) for non-infectious posterior uveitis. Ophthalmology
2006;113:1020-27.
3. Kempen JH, Altaweel MM, Holbrook JT. Randomized comparison
QH U[UVGOKE CPVKKPƀCOOCVQT[ VJGTCR[ XGTUWU ƀWQEKPQNQPG
acetonide implant for intermediate, posterior, and panuveitis: the
multicenter uveitis steroid treatment trial [MUST]. Ophthalmology
2011;10:1916–26.
#PVQU[M #0 (#/' +PXGUVKICVQTU 'HſECE[ CPF 5CHGV[ QH +.78+'0
4
(Fluocinolone Acetonide [FAc] Intravitreal Insert) for the Treatment
of Diabetic Macular Edema. ARVO Meet Abstr 2011;52:6645.
.GG 5; %JGG 52 5WTQFGZ CHVGT RJCEQGOWNUKſECVKQP , %CVCTCEV
Refract Surg 2005;31:1479–80.
6. Kim, J, Peng CC, Chauhan A. Extended release of dexamethasone
from silicone-hydrogel contact lenses containing vitamin E. J Control
Rel. 2010; 148:110-16.
7. De Kozak Y, Andrieux K, Villarroya H. Intraocular injection of
tamoxifen-loaded nanoparticles:A new treatment of experimental
autoimmune uveoretinitis. Eur J Immunol. 2004; 34:3702-12
8. Sakai T, Kohno H, Ishihara T, et al. Treatment of experimental
autoimmune uveoretinitis with poly(lactic acid) nanoparticles
encapsulating betamethasone phosphate. Exp Eye Res. 2006;
82:657-63.
Figure 5: 2FX3KRU LRQWRSKRUHVLV VVWHP $SSOLFDWRU LV SODFHG
over the sclera under the lower eyelid