Study on the Impact of Ocular Anesthetic Procedures in Ocular Blood Flow
Open Angle GlaucomaAnaesthetic procedures in ophthalmology surgery have been a subject rapidly evolving in the past decades. When deciding for a retrobulbar block, the local injection of varying mixtures and volumes of fast-acting anesthetics (such as lidocaine) - with or without a vasoconstrictive agent (such as adrenaline) - coupled with Hyaluronidase have been the standard care to provide painless surgery while minimizing the possible risks such as increased intraocular pressure (IOP), brainstem anesthesia, toxic reaction and ocular blood flow changes. These iatrogenic-induced vascular dysfunctions have been also suggested to play a role in intra-operatory vision loss (a "wipe-out" phenomenon) in patients with advanced glaucoma. The rationale for the use of epinephrine in retrobulbar anesthesia is to slow absorption of the anesthetic in general circulation and thus to achieve a longer effect in the orbit. However, studies on ocular blood flow after adrenaline-containing compounds have consistently showed a decrease in ocular blood flow, thus raising the issue of whether it should be used in patients with known vascular dysfunction, namely glaucoma patients. Nevertheless, there has been no study to verify this claim concerning the safety of non-adrenaline containing anesthetics. Injecting a pre-determined volume of anesthetic compound behind the globe, regardless of its formulation has also been debated. The orbital pressure increase can lead to a number of adverse reactions, not only increasing IOP but also potentially decreasing vascular input by local compression. In glaucoma for instance, there has been suggested optic nerve sheaths to be less elastic than in healthy individuals, potentially making this structure less compliant to outside compression. These more rigid orbital tissues could also impair the orbit's ability to deal with the iatrogenic increased volume. As seen, the current concepts on the impact of ocular anesthesiology in the orbit and the vascular supply to the eye are limited to a small number of non-homogeneous studies. We aim to study this impact through a non-invasive, widely established ultrasound based method of ocular blood flow research (color Doppler Imaging). Potentially, our study could help determine a taylor-made choice of the anesthesiology procedure to apply to a specific patient, thereby advancing the current standard of care in ophthalmology.
PAIR Study-PAP And IOP Relationship: Study 2
Obstructive Sleep ApnoeaPrimary Open-angle GlaucomaSome people with Primary Open-angle Glaucoma (POAG) also suffer from Obstructive Sleep Apnoea (OSA), a common sleep disorder which is known to affect heart and blood vessels, and may contribute to glaucoma progression. Obstructive Sleep Apnoea is treated with Continuous Positive Airway Pressure (CPAP); however using this type of breathing support may raise intraocular pressure (IOP). The evidence for this is limited and the potential mechanisms involved are poorly understood. In this study we will determine whether CPAP applied at night changes IOP and ocular perfusion pressure (OPP). We will also assess its possible impact on ocular microvasculature. Two groups of patients will be included: those with POAG and OSA, and those with OSA without glaucoma. They will attend for two overnight assessments: the first before starting CPAP and the second 4-6 weeks into the treatment. Repeated measurements of IOP at night will be performed and participants will continue self-measuring IOP at home in the day. An Ocular Coherence Tomography Angiography (OCT Angiography) of the optic disc and the surrounding retina will be performed at baseline and after a few weeks of CPAP treatment.
Treatment Outcomes of a Novel Glaucoma Tube Shunt Implant for Intraocular Pressure Control in Eyes...
GlaucomaGlaucoma3 moreThe aim of this study is to determine the effectiveness of lowering intraocular pressure and safety profile of the Paul Glaucoma Implant (Advanced Ophthalmic Innovations, Singapore). This is a non-comparative and single-arm observational study and all the participants were recruited between 1 Dec 2017 and 1 Dec 2018. Patients between age 21 - 80 years with glaucoma and an IOP deemed poorly controlled by the study team despite on maximal tolerated medical therapy were included in this study. The participants were recruited from 6 tertiary ophthalmology centers including National University Hospital, Singapore, Moorfields Eye Hospital, United Kingdom, St Thomas' Hospital, United Kingdom, Chulalongkorn University and Hospital, Thailand, International Specialist Eye Centre, Malaysia and Chinese University of Hong Kong, Hong Kong. All the eyes were followed-up for a period of 12 months after surgery. The examination and investigations included best corrected Snellen visual acuity, slit lamp examination, goldman applanation tonometry (GAT), dilated fundus examination and optic nerve head imaging. The participants are reviewed before surgery, 1 day, 1 week, 1 month, three months, 6 months and 12 months after surgery. All the data were captured in a standardized data-collection form for analysis. The primary outcome measure was failure, if was prospectively defined as IOP more than 21mmHg or less than a 20% reduction compared to pre-operative baseline on 2 consecutive visits after 3 months, IOP less than 6 mmHg on 2 consecutive visits after 3 months, reoperation for IOP-related indication, loss of light perception vision, or removal of the implant for any reason. Intraocular pressure outcomes, number of IOP-lowering medications and the rate of surgical complications were secondary outcome measures in this study.
Observational Study of Lumigan® 0.01% Treatment for Patients With Primary Open Angle Glaucoma or...
GlaucomaOpen-Angle1 moreThis study will assess the efficacy, safety, tolerability and persistence of use of Lumigan ® 0.01% in patients diagnosed with primary open-angle glaucoma or ocular hypertension who are treated per routine clinical practice.
The Effectiveness of Topical Latanoprost Compared With Topical Brimonidine in the Treatment of the...
To See the Safety and Efficacy of the Topical Latanoprost Compared With Topical Brimonidine in the Treatment of the Primary Open Angle Glaucoma PatientsOutpatient department of cmch, ceitc,cimch POAG patients enrolled for the study.
Comparison of Efficacy & Tolerability Between Ganfort vs Krytantek in Mexican Patients With Primary...
Glaucoma Primary Open AngleThe objective of this phase IV clinical multi-center trial will be to compare the efficacy and safety of Ganforti® versus Krytantek®, using a cross-over design during a six month period (including a one-month wash-in period) in POAG and OH patients.
Multicentric Observational Study on Quality of Life in Glaucoma
Primary Open-angle GlaucomaThe study aims to evaluate the quality of life (QoL) of patients affected by Primary Open-Angle Glaucoma (POAG), using 2 QoL questionnaires: Glaucoma Symptom Scale (GSS) and National Eye Institute Visual Function Questionnaire (NEI-VFQ -25). The study will be conducted on patients with well known diagnosis of POAG (transversal phase) and on patients with first diagnosis of POAG (longitudinal phase).
Re-Trabeculectomy Versus Ahmed Glaucoma Valve Implantation in Secondary Surgical Management of Patients...
Refractory Primary Open Angle GlaucomaThe purpose of this study is to compare three-year outcomes of re-trabeculectomy with those of Ahmed glaucoma valve implantation in secondary surgical management of patients with primary open angle glaucoma (POAG) and a history of previous failed trabeculectomy.
Safety and Performance Study of the CyPass System Applier Model 241
Open Angle Glaucoma (OAG)This is a retrospective chart review of cases in which the CyPass Micro-Stent was implanted using the Model 241 Applier. The objective of this study is to characterize and evaluate the safety of the Model 241 Applier when used for CyPass Micro-Stent implantation.
A Study of Lumigan® 0.01% in Patients With Primary Open Angle Glaucoma (POAG) or Ocular Hypertension...
GlaucomaOpen-Angle1 moreA study of Lumigan® 0.01% as administered in standard practice for patients with POAG or OHT. All treatment decisions, care and diagnostic procedures provided are at the discretion of the participating physicians according to their clinical judgment and the local standard of medical care.