Intraocular Pressure

To evaluate the changes that occur in the intraocular pressure before and after corneal cross linking using Corvis CT.

Glaucoma medications are vital to disease management and prevention of further loss of vision as over time glaucoma will lead to irreversible blindness. The average size of a glaucoma medication bottle is around 10cc and these medications when used 2-3 times daily are expected to last patients an entire month. The investigators found that at Boston Medical Center (BMC) a majority of Yawkey Eye Clinic patients are unable to deliver the drops into their eyes due to poor vision or difficulty squeezing drop bottles. These patients also often deliver more than a necessary amount leading to premature completion of the bottle. However, because the cost benefit ratio of these drop aids is unclear, they are not routinely offered to the patients. Although the efficacy of these drop aids has not been well studied, if effective, the cost of these drop aids would more than pay themselves by improving medication compliance and visual function of the patients. This study aims to determine the efficacy of the Nanodropper in the BMC Yawkey Eye Clinic patient population.

To evaluate the changes that occur in the intraocular pressure after corneal refractive surgery either PRK , LASIK and femtosecond laser by using Corvis CT results and applanation tonometer

Steep Trendelenburg positioning and insufflation of the abdominal cavity have shown to increase intra ocular pressure. Different anesthetic techniques can alter intra ocular pressure and a small pilot study showed decrease in Intraocular Pressure (IOP) in robotic case in steep Trendelenburg with IV anesthetics (TIVA). We want to quantify the degree of change in Intraocular Pressure (IOP) in female patients undergoing robotic procedures for cancer. We want to detect the difference in increase of pressure with total IV anesthesia versus conventional balanced anesthesia

This study is to investigate the relationship between arterial carbon dioxide (CO2) concentration and vitreous pressure on the choroidal volume by integrated intraoperative OCT imaging under eye exams under anesthesia.

The primary objective of this study is to utilize the Airofit device to systematically measure and characterize the changes in intraocular pressure across its six different levels of forced expiration. This investigation will provide crucial quantitative data on the IOP-respiratory effort relationship, enhancing our understanding of IOP dynamics during controlled respiratory stress and establishing a new, standardized paradigm for such research.

Rationale: The cornea is the most transplanted tissue in the Netherlands, with more than 1,500 procedures performed each year. A minimally invasive technique called Descemet Membrane Endothelial Keratoplasty (DMEK) has become the preferred method in the past decade. The main advantage of DMEK over previous techniques is a low graft rejection rate (1-2% per year). Despite this, rejection prophylaxis after DMEK follows the same high potency regimen as previous techniques in the first year, and patients are burdened with indefinite immunosuppression. The current project, OPTIMISE, aims to establish an evidence-based, cost-effective regimen that effectively prevents rejection and minimizes side effects. Corticosteroid eye drops are the mainstay of ocular immunomodulatory therapy. Their main side effect is a steroid-induced increase in intraocular pressure (IOP). It manifests in about one-fourth of patients within the first year after surgery and can lead to irreversible optic nerve damage and vision loss. Patients with IOP elevation require additional medications and hospital visits resulting in reduced quality of life and increased costs. The optimal dosing regimen in the first year after DMEK and whether patients may safely stop steroids after one year remains unknown. As a result, protocols in the Netherlands vary considerably from surgeon to surgeon. Patients are potentially over-treated in the short and long-term, resulting in undue burden for the patient and increased costs. Consequently, the Dutch Ophthalmology Society (NOG) identified the optimal short- and long-term immunosuppressive protocol for corneal transplantation as one of its Top 10 knowledge gaps, underscoring relevance for clinical practice. With this work, the investigators expect to address this knowledge gap to the benefit of our patients and society. Objective: The OPTIMISE study aims to establish an evidence-based, cost-effective regimen that effectively prevents rejection and minimizes side effects. The hypothesis of this study is that Fluorometholone 0.1% in the first year and discontinuing medication in the second year is a cost-effective treatment strategy after DMEK. Study design: The design of this study is a randomized, controlled multicentre trial with a duration of 24 months. Study population: The study population will consist of 342 patients aged 21 years or older undergoing DMEK surgery in one eye. Intervention: All patients will receive Descemet's Membrane Endothelial Keratoplasty. Following this procedure, patients will be randomized into the following post-operative regime in two stages: STEP-I (Year 1): Control group: DMS 0.1% 6 times a day for 1 month tapered off to once daily within 6 months and then once a day for 6 months. Intervention group: DMS 0.1% 6 times a day for 1 month followed by FML 0.1% 4 times a day for two months tapered off to once daily within four months and then once a day for 6 months. STEP-II (Year 2): Control Group: Half the patients in each study arm will use FML 0.1% daily. Intervention Group: Half the patients in each study arm will discontinue steroids. Main study parameters/endpoints: Primary outcomes: Step-I: IOP elevation compared to baseline Step-II: Endothelial cell loss (ECL) in the second year Secondary outcomes are: * Rejection free graft survival. * Patient reported outcome measures. * Incremental cost-effectiveness ratios, including a short term trial-based economic evaluation (TBEE) and a life-long model-based economic evaluation (MBEE) * Structural outcomes including corneal, central macular and retinal nerve fibre layer thicknesses, and optic nerve head imaging.

The aim of this study is to examine the effects of intraoperative systemic use of dexmedetomidine on the intraocular pressure (IOP) in patients undergoing spine surgeries in a prone position under general anesthesia.

Laminectomy surgeries, typically performed for lumbar disc herniation and spinal disorders, are often lengthy surgical procedures requiring patients to be in the prone position. While this position provides better visibility of the surgical field, it can lead to physiological changes in intraocular pressure (IOP) in anesthetized patients. An increase in IOP, though rare, has the potential to cause severe ocular complications such as postoperative vision loss (POVL), which is one of the most feared complications after spinal surgery. One of the main mechanisms of IOP elevation in the prone position is the impediment of venous return in the head and neck region due to gravity, leading to an increase in episcleral venous pressure. Additionally, direct mechanical pressure on the face and globe can also increase IOP. Anesthesia management can also play a role in IOP dynamics by affecting intrathoracic pressure and venous return. This complex interaction necessitates careful monitoring of eye health in anesthetized patients in the prone position. Non-contact tonometers offer a non-invasive, rapid, and reliable method for IOP measurement. They are particularly advantageous for repeated measurements in anesthetized patients. This clinical study aims to evaluate changes in IOP using a non-contact tonometer in patients undergoing laminectomy in the prone position and to identify anesthesia- and patient-related factors influencing these changes. The data obtained will contribute to the development of anesthesia and positioning strategies aimed at reducing the risk of ocular complications.

Glaucoma is a multifactorial disease, an important risk factor of which is increased intraocular pressure. Fluctuations in intraocular pressure are often associated with vaginal birth, although intraocular pressure during active pushing during stage II has never been measured.. The study will be conducted on a group of patients with healthy eyes on patients who have completely fine vision or have a small refractive error and are accustomed to wearing contact lenses. The measurement of intraocular pressure itself will be carried out using SENSIMED Triggerfish contact lenses, which measure pressure every 5 minutes for 30s. This period roughly corresponds to the duration of 1-2 contractions. Inclusion in the study will be offered to patients in the 35th to 37th week of pregnancy. Prior to measurement patients will be sent to an eye clinic for a detailed examination of both eyes, which includes measuring intraocular pressure. Subsequently, pregnancy checks will take place according to the standard scheme and in the standard scope. At the onset of uterine contractions, an ophthalmologic consultant will be called, which will measure intraocular pressure between contractions using the Tonopen device and put on SENSIMED Trigerfish contact lenses in combination with a local anesthetic. The patient will have these lenses until the end of the third stage of labor, i.e. 2 hours after the birth, when the lenses are removed. In the second stage of labor, continuous monitoring by a cardiotocograph will take place. Subsequently, the obtained data from the cardiotocograph and contact lenses will be evaluated and compared by a team of ophthalmologists and gynecologists, where the investigators will be able to assess the individual fluctuations in intraocular pressure depending on the individual contractions. The aim of the study is to demonstrate or disprove the risks to the glaucoma patient due to increased intraocular pressure during active pushing in combination with uterine contraction.

The goal of this prospective controlled study is to measure the reliability of two intraocular pressure (IOP)-measuring instruments in comparison to the gold standard, Goldmann applanation tonometry (GAT) following vitreo-retinal surgery. The main question the current study aims to answer is: are Icare and Accupen as accurate as GAT in measuring IOP one day post eye surgery? Participants in this study will have their IOP measured by the three different instruments one day post-surgery.

This clinical trial used acupuncture as an adjunctive treatment for glaucoma patients. A randomized, controlled trial involving 50 subjects will be conducted and observed for 12 weeks to evaluate the clinical efficacy of acupuncture. This study aims to provide a reference for future clinical treatment guidelines.

The purpose of this study is to improve understanding of the pathophysiologic process that leads to the development of glaucamotous damage. The mechanism by which vision loss in glaucoma occurs is still unknown, but it is clear that increased intraocular pressure (IOP) is a major risk factor. It is also thought that the LC is a site of primary damage during pathogenesis of the disease. This prospective study with determine the in-vivo mechanical response to IOP modulation at the level of the ONH and LC.