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David J. Calkins, PhD, is Assistant Vice President for Research at Vanderbilt University Medical Center and Chair of the Glaucoma Research Foundation Research Committee and the Catalyst for a Cure Advisory Board.

New strategies are needed to rethink how we treat glaucoma to do more than just manage eye pressure—to actually restore vision by promoting the survival of retinal ganglion cells and their axons.

Restoring vision in glaucoma: more than meets the eye

A recurring feature at the 2024 American Society of Cataract and Refractive Surgery (ASCRS) Annual Meeting in Boston, Massachusetts, was the call for environmentally friendly practices worldwide, with the goal of decreasing the impact of ophthalmic surgeries on the planet.

A driving force in this movement is EyeSustain

 an organization dedicated to the development of such friendly environmental practices, that exists as a global coalition of eye societies providing education and resources to support sustainable practices in ophthalmology.

Here is a sampling of the ASCRS discussions on the topic.

Greening eye care: reducing ophthalmology’s environmental footprint

The presenters, led by first author Sarishka Desai, BA, described the EyeSustain platform and its 5-pronged mission: educate the global ophthalmic community about more sustainable practices, collaborate with industry to reduce our carbon footprint and surgical waste, support research and innovative solutions that reduce ophthalmology’s environmental impact, support advocacy and education about the public health impact of climate change, and collaborate with industry to reduce our carbon footprint and surgical waste.

Desai, of the University of Connecticut School of Medicine in Farmington, and colleagues presented EyeSustain’s approach to reducing the ophthalmic carbon footprint. She was joined in the study by Nitya Devireddy, BS, MPH, of Penn State College of Medicine in Hershey, Pennsylvania; Sofia Miguez, BA, of Yale School of Medicine in New Haven, Connecticut; and Barbara Erny, MD, of the Department of Ophthalmology at Stanford University in California.

The greenhouse gas data associated with health care are startling. Health care is responsible for 4.4% of all global greenhouse gas emissions, 71% of which arise from the manufacturing, use, and disposal of medical supplies. Ophthalmology has the highest procedural volume of any surgical specialty, with 50 million cataract surgeries expected to be performed globally each year by 2050, Desai reported.

In light of the procedural data, the authors highlighted 6 areas that are currently undergoing research and quality improvement initiatives through the EyeSustain system.

 of cataract surgeons and nurses by David Chang and Cassandra Thiel found that 93% of respondents believe that the trash associated with OR procedures is excessive, and that methods to reduce waste should be identified and implemented.

 encouraged regulatory agencies to allow electronic instructions for use be disseminated in lieu of the traditional paper instructions included with each cataract pack.

Ongoing projects spearheaded by EyeSustain members, including medical students and ophthalmology residents, are taking a look at educating surgeons and surgical staff about sustainability and the impact of OR waste, OR water consumption, and evaluation of flash sterilization associated with cataract surgery.

In recognition of the fact that medications in the OR represent an estimated $560 million in waste annually, a multisociety position paper

 recently formulated 3 key recommendations: topical drugs in multidose containers can be used for multiple patients in surgical facilities if proper guidelines are followed; topical drugs in multidose containers can be used until the manufacturer’s labeled date of expiration if proper guidelines are followed; and, when applicable, patients should be able to take their partially used medication home for postoperative use.

The Aravind Eye Care system’s low-carbon model from Madurai, India, uses alternate energy sources, transport, infrastructure, and equipment maintenance.

 Studying global systems of eye care and waste produced can provide a deeper understanding of the impact of hospitals and providers on climate change, as well as ideas on how western eye care systems can proactively reduce carbon emissions.

The EyeSustain platform includes ophthalmology-specific action steps for greening offices and clinics in collaboration with the 

Partnerships can be established with large manufacturers to reduce packaging, make instruments reusable, and streamline the manufacturing and distribution processes.

In addition to the impact of practice waste on the environment, EyeSustain also recommends studying the effects of climate change on the incidence rates of ophthalmologic conditions, including cataracts, allergic disease, and glaucoma, among others.

Desai and her colleagues recommended that institutions take the following steps:

Conduct a waste audit to quantify the carbon footprint of an institution’s OR emissions. This includes using the EyeSustain-Zasti Carbon Footprint Calculator, using the Sustainability Index for Disposables in Cataract Surgery calculator for cataract packs to evaluate the item-by-item potential for carbon dioxide savings, and surveying clinical staff to identify areas of perceived excess waste.

Identify key stakeholders at an institution and an enthusiastic, multidisciplinary team and completing the OR Sustainability Pledge (

), which has been completed by ambulatory surgery centers/hospital outpatient departments from 9 countries thus far.

Implement best practices; multisociety recommendations for sustainability are easily accessible at eyesustain.org and My Green Doctor for outpatient/clinic resources and local legislation using the American Academy of Ophthalmology Topical Medical Waste Reduction Act legislative template.

Using phacoemulsification waste to guide changes in surgical sustainability

Adjustments to improve the sustainability of ophthalmic surgical practice can have a large impact when scaled to case volume, according to author Margaret Tharp, BSc, who described this study at the ASCRS meeting. She and her coauthors Stella Protopapas, BA, MPH, and Minka Gill, BSc, are from the Indiana University School of Medicine in Bloomington, whereas David J. Palmer, MD, ABO, is from the Northwestern University Feinberg School of Medicine in Chicago, Illinois.

In their study, they sought to draw connections between results from a 24-hour waste audit at an outpatient surgical center and current resources available from EyeSustain to improve the sustainability of ophthalmic surgical practice.

The authors documented the extensive waste generated from 1 day of surgeries in an institution that included 13 phacoemulsification procedures, 5 plastic surgeries, 3 urologic surgeries, and 5 otolaryngologic cases. The waste products were sorted as medications (eg, propofol, eye drop containers), textiles (eg, surgical gowns, drapes), metals (eg, metal wiring, disposable instruments), and plastics (eg, hard, soft, wrappings).

When the amounts of the waste products were tallied, the authors found that “ophthalmology produced the greatest amount of waste in a single day relative to other operating specialties, despite producing the least amount of waste per case. Most ophthalmic waste was from textiles, hard plastics, and medications,” the authors reported.

The specific 13 phacoemulsification procedures resulted in 95.4 lb of waste broken down as follows: 18.5 lb of hard plastic, 5.5 lb of soft plastic, 8.3 lb of wrapping, 13.5 lb of medications, 41.2 lb of textiles, 6.7 lb of miscellaneous waste, and no metals. Compared with other operating specialties, ophthalmology produced the least amount of waste per case but the greatest amount of waste in total due to the relatively high case volume.

It has been reported that “discarded/unused pharmaceuticals from US cataract surgeries demonstrated waste of [approximately] $150 per case while generating carbon dioxide–equivalent emissions that approximated 25,000 to 100,000 flights from San Francisco, California, to Boston annually.

Small changes can have dramatic results. Tharp and colleagues suggested that the following would have positive consequences.

Revising the use of tetracaine bottles intraoperatively; for example, reusing the bottles between cases or sending the bottles home with patients

Optimizing packaging of surgical supplies and electronic instructions

Utilizing intravenous sedation to limit anesthesia gas carbon dioxide–equivalent emissions

Focusing on cutting waste also creates an opportunity to explore the practices of global leaders in sustainable eye care, such as the efforts of the Aravind Eye Hospitals, which provide similar surgical success rates at a fraction of the waste produced by US practices.

 A downside may be that such practices require significant reuse of materials, central sterilization, and stakeholder diligence, which can require complex interventions, according to Tharp. 

EyeSustain’s Surgical Facility Sustainability Pledge can serve as a guide for ophthalmologists to improve the sustainability of their practice in an approachable and lasting manner.

Factors contributing to the carbon footprint of cataract surgery

Omar Taboun, MSc, a medical student at Western University’s Schulich School of Medicine & Dentistry in London, Ontario, Canada, working under the direction of Netan Choudhry, MD, FRCSC, also described the negative impact of cataract surgery on the environment at the ASCRS meeting.

He commented, “We know that climate change can affect human health through various means, such as adverse weather events causing injury and exposure to pollutants [exacerbating] underlying health conditions. As health care providers, it is our responsibility to treat patients for their conditions that may ultimately be influenced by environmental factors. Counterintuitively, the health care sector is itself a greenhouse gas emitter,” Taboun said.

Surgery contributes significant emissions to the environment through the necessary materials and tools used during procedures. In addition, the need to maintain sterility increases waste.

The term footprint indicates the sum of all emissions direct and indirect resulting from this procedure, Taboun explained, the resultant value of which is typically reported in carbon dioxide equivalents

And although cataract surgery requires only a few minutes to complete, the procedural volume has increased exponentially over the past 2 decades,

Taboun and colleagues developed a 2-fold goal: they wanted to increase their understanding of the carbon footprint and waste accumulation to identify the primary contributors and pinpoint areas for improvement to enhance the sustainability of cataract surgery.

They conducted a literature search of PubMed, Google Scholar, and Medline to identify studies related to the carbon footprint and the elements of cataract surgery. The results yielded 6 studies, with 2 being the basis for this discussion,

He highlighted 3 main points extracted from the published data: the lowest footprint published was just under 6 kg of carbon dioxide equivalents; the highest published footprint was just over 180 kg of carbon dioxide; and the major factors contributing to the footprint include procurement of pharmaceuticals and materials, building and energy use, such as heating/cooling, lighting, electricity-powered tools, and travel by patients and staff to the location where the procedure is performed.

Taboun directed attention to centers that already have sustainable practices in place, such as the Aravind Eye Hospital, which reports the lowest footprint. These sustainable practices include the use of multiple operating tables in a single room; reusing gloves, gowns, and various medical equipment;

and using highly efficient autoclave settings.

Importantly, when these changes were implemented in the Aravind Eye Hospital,

 the rates of endophthalmitis remained comparable to other centers: 0.02% vs from 0.04% to 0.07% reported.

Taboun offered 3 ways that surgeons can offset the negative effects of cataract surgery on the environment—by focusing on procurement, energy use, and travel emissions.

Reduce emissions associated with procurement by collaborating with manufacturers to reduce packaging as much as possible and encouraging recycling in every OR.

Reduce building and energy use by incorporating renewable energy, such as solar panels, and more strategic lighting protocols and optimizing energy use within surgical centers.

Establish outreach clinics closer to more populous regions, whereby mostly staff members must travel, and patients less so, which will reduce travel emissions, along with performing bilateral procedures.

“Implementing sustainable practices, although challenging, will allow us to continuously provide this procedure and restore vision for millions of people at less of a cost to the environment,” Taboun said.

1. Chang DF, Thiel CL; Ophthalmic Instrument Cleaning and Sterilization Task Force. Survey of cataract surgeons’ and nurses’ attitudes toward operating room waste

. 2020;46(7):933-940.doi:10.1097/j.jcrs.0000000000000267

2. Schehlein EM, Hovasesian J, Shukla AG, Talley Rostov A, Findl O, Change DF. Reducing ophthalmic surgical waste through electronic instructions for use: a multi-society position paper. 

. 2024;50(3):197-200. doi:10.1097/j.jcrs.0000000000001381

3. Cleaning and Sterilization Task Force. Reducing topical drug waste in ophthalmic surgery: multisociety position paper

. 2022;48(9):1073-1077; doi:10.1097/j.jcrs.0000000000000975

4. Goel H, Wemyss TA, Harris T, et al. Improving productivity, costs and environmental impact in International Eye Health Services: using the ‘Eyeficiency’ cataract surgical services auditing tool to assess the value of cataract surgical services. 

. 2021 ;6(1):e000642. doi:10.1136/bmjophth-2020-000642. 2021

5. US EPA O. Greenhouse gas equivalencies calculator. United States Environmental Protection Agency. Updated January 2024. https://www.epa.gov/energy/greenhouse-gas-equivalencies-calculator

6. Gadani H, Vyas A. Anesthetic gases and global warming: [otentials, prevention and future of anesthesia. 

. 2011;5(1):5-10. doi:10.4103/0259-1162.84171

7. Thiel CL, Schehlein E, Ravilla T, et al. Cataract surgery and environmental sustainability: waste and lifecycle assessment of phacoemulsification at a private healthcare facility. 

. 2017;43(11):1391-1398. doi:10.1016/j.jcrs.2017.08.017

8. Pandey D, Agrawal M, Pandey JS. Carbon footprint: current methods of estimation. 

. 2011 ;178(1-4):135-160. doi:10.1007/s10661-010-1678-y

9. Pandey D, Agrawal M, Pandey JS. (2011). Carbon footprint: current methods of estimation. 

. 2011;178(1-4):135-160. doi:10.1007/s10661-010-1678-y

10 Rachmiel R, Trope GE, Chipman ML, Buys YM. Cataract surgery rates in Ontario, Canada, from 1992 to 2004: more surgeries with fewer ophthalmologists. 

11. Morris DS, Wright T, Somner JEA, Connor A. The carbon footprint of cataract surgery. 

. 2013;27(4):495-501. doi:10.1038/eye.2013.

12. Latta M, Shaw C, Gale J. The carbon footprint of cataract surgery in Wellington. 

13. Ravindran RD, Venkatesh R, Chang DF, Sengupta S, Gyatsho J, Talwar B. Incidence of post-cataract endophthalmitis at Aravind Eye Hospital: outcomes of more than 42,000 consecutive cases using standardized sterilization and prophylaxis protocols. 

. 2009;35(4):629-636. doi:10.1016/j.jcrs.2009.01.002

14, Pershing S, Lum F, Hsu S, et al. Endophthalmitis after cataract surgery in the United States: a report from the Intelligent Research in Sight registry, 2013-2017. 

. 2020;127(2):151-158. doi:10.1016/j.ophtha.2019.08.026

Organization eyes green practices, shifting ophthalmology landscape.

Minimizing the carbon footprint of ophthalmic surgeries

AAO-2024-Biousse-OT

Valerie Biousse, MD, from the Emory University in Atlanta, Georgia, shared insights on how ocular imaging in the emergency department can provide timely, accurate diagnosis while also benefiting the on-call ophthalmologists. She shared these thoughts at this year's AAO meeting held in Chicago, Illinois. 

Editor's note: The below transcript has been lightly edited for clarity.

I am Valerie Biousse, a neuro-ophthalmologist at Emory University in Atlanta. I am a big fan of having non-mydriatic fundus cameras in emergency departments, and we have a few presentations on this topic at the AAO meeting.

As you know, nobody really uses ophthalmoscopes in emergency departments anymore, and cameras are great because they facilitate the examination of the ocular fundus by non ophthalmologists, and they also allow for remote interpretation of the pictures by ophthalmologists. So instead of ophthalmoscopes, we have a camera connected to our electronic health record with an entirely automated process and integration of the camera into the ED flow. 

This has proven very useful, because the camera allows the ophthalmologist on call to make some diagnosis remotely, without in person consultation. So for example, if an acute central retinol artery occlusion is abuse on ocular imaging, we do not even come to the hospital anymore, and instead, we trigger a stroke alert, which prompts neurology to take care of the patient immediately, and not having to wait for an ophthalmologist to come to the emergency department or wait for pupillary dilation to look at the fundus is saving a lot of time, and it is allowing us to occasionally recommend treatment of acute central retinol artery oclusion with thrombolysis within just a few hours of vision loss, which is amazing. That has allowed us to design a nice stroke protocol, which has become standard of care at our institution. 

Another great use of the camera in the emergency department is when a patient has headaches or is sent to the emergency department to roll out papilledema, presumably from a neurologic disorder. In this case, we just review the pictures remotely, instead of having to come to the ED in the middle of the night for a fundus examination. We showed that this new flow has reduced the ED length of stay by at least 50% for patients sent to the ED mostly to rule out papilledema, and that more than 90% of patients were able to have papilledema ruled out remotely, without an in-person consultation. And you can imagine that this has made our on-call ophthalmologists, including our residents, very happy. So these are the main reasons why I think we really need to work at helping our emergency department colleagues implement such cameras in general emergency departments, especially given the anticipated worsening shortage of ophthalmologists and neuro-ophthalmologists in our country. 

Being able to provide adequate ophthalmic examinations in the ED, including remotely, with either implementation of e-consultation or teleophthalmology will become essential, and cameras will help us do that. To take the pictures are obtained directly by the ED staff, and anyone can do it. Currently, we have the technicians who are in charge of doing EKGs in the ED, they were trained. The training takes about 10 minutes. They take the pictures themselves, and that's why the key is to have a very user-friendly camera with only 1 button to push and the pictures happen. 

The interpretation is a little more complex. The pictures are readily available to the ED providers and to the neurologists on the electronic medical records. Some of them are comfortable reviewing the pictures themselves, and they interpret them without our help. And it's particularly useful when the pictures are normal. So for example, if all they want to do is rule out papilledema, then in most situations, they do it themselves, and they don't even call us. 

On the other hand, if the picture looks abnormal, they page us, and we review the pictures live for them so that they get an immediate interpretation. In all cases, I always reassure them. We tell them, "we have your back," because in all cases, 1 ophthalmologist reviews the pictures, usually within 24 hours, in order to double check that the original interpretation was correct and to be able to bill.

Ocular imaging in emergency departments, particularly using non-mydriatic fundus cameras, enhances diagnostic efficiency and supports remote interpretation by ophthalmologists. This technology allows for timely interventions, such as triggering stroke alerts for acute central retinal artery occlusion, and reduces emergency department length of stay by enabling remote diagnosis of conditions like papilledema. The integration of these cameras into emergency department workflows is crucial, especially given the anticipated shortage of ophthalmologists. Training for ED staff is minimal, and the process supports teleophthalmology and e-consultation initiatives.

Canonical

AAO 2024: Ocular imaging in the emergency department can provide timely, accurate diagnosis

Sun Pharmaceutical presented Phase 4 data at ESCRS 2024 showing that cyclosporine ophthalmic solution 0.09% significantly improves dry eye disease symptoms and corneal staining in patients inadequately controlled on Restasis, with positive results observed through 12 weeks of treatment.

Sun Pharmaceutical Industries Ltd. presented Phase 4 data further demonstrating that cyclosporine ophthalmic solution (Cequa) 0.09% induces sustained improvement in the signs and symptoms of dry eye disease (DED) in patients previously prescribed cyclosporine ophthalmic emulsion (Restasis) 0.05%, whose DED was inadequately controlled.

In the presentation at the European Society of Cataract and Refractive Surgeons (ESCRS) 2024 annual meeting in Barcelona, Spain, researchers reported that patients showed significant improvements in both total corneal staining and visual acuity after being treated with cyclosporine ophthalmic solution 0.09%.

This Phase 4, multicenter, open-label, single-arm study of DED patients not adequately controlled after treatment with Restasis and switched to cyclosporine ophthalmic solution 0.09% demonstrated significant improvements from baseline in both total Corneal Fluorescein Staining (CFS) and Best Corrected Visual Acuity (BCVA) at Week 12. CEQUA demonstrated significantly reduced total CFS scores from Week 4 through Week 12 of the study, and patients treated with cyclosporine ophthalmic solution 0.09% showed significant improvement in BCVA at Week 8 and Week 12.

The Phase 4 study enrolled 134 adults with a history and clinical diagnosis of DED who were inadequately controlled on Restasis therapy (based on severity of accepted signs and/or symptoms of DED) for at least three months before screening/baseline. Investigators assessed CFS and BCVA scores at baseline and at Weeks 4, 8, and 12, and/or upon early discontinuation from the study.

Discontinuations were low; 19 of 134 patients discontinued for any reason. Throughout the study, 84 patients (62.7%) reported at least one treatment-emergent adverse event (AE), while the majority of AEs were mild in severity (73.8%) and most commonly related to installation site pain. Serious AEs occurred in less than 2% of study patients, and only five patients discontinued the therapy and study because of AEs.

Cequa is the first and only FDA-approved cyclosporine treatment delivered with nanomicellar NCELL technology. NCELL technology is believed to improve the bioavailability of cyclosporine and enhance ocular penetration.

“It is extremely encouraging to see such positive results from treatment with Cequa amongst Restasis patients who were inadequately controlled,” said investigator and presenter Michelle Hessen, OD, of the Wilmer Eye Institute in Baltimore, Maryland. “Combined with previous results from the Phase 4 study, we are pleased to report that at 12 weeks, study participants experienced significant improvements across several major signs and symptoms, including corneal fluorescein staining, modified Symptom Assessment in Dry Eye, and visual acuity.”

Sun Pharmaceutical's Phase 4 study demonstrated that cyclosporine ophthalmic solution 0.09% (Cequa) significantly improves dry eye disease symptoms and corneal staining in patients inadequately controlled on Restasis. Conducted at the ESCRS 2024 meeting, the study showed sustained improvements in corneal fluorescein staining and best corrected visual acuity over 12 weeks. The study enrolled 134 patients, with low discontinuation rates and mostly mild adverse events. Cequa, utilizing nanomicellar NCELL technology, enhances cyclosporine bioavailability and ocular penetration, offering a promising alternative for inadequately controlled dry eye disease patients.

Sun Pharma announces positive Phase 4 data results in dry eye disease 

This Week in Ophthalmology thyroid eye disease (TED) Prevent Blindness

This Week in Ophthalmology 

 Hello, I am David Hutton of Ophthalmology Times, and welcome to another episode of This Week in Ophthalmology, a program that looks at some of the current headlines and hot topics from Ophthalmology Times.

This week, we will focus on thyroid eye disease.

Prevent Blindness has designated November 18 to 24, 2024, as the 5th annual Thyroid Eye Disease (TED) Awareness Week. The week aims to raise awareness of TED's symptoms, impact on vision and mental health, and new treatment options. Educational resources and expert-led episodes will support patients and healthcare professionals.

TED was a topic of discussion at the American Academy of Ophthalmology’s annual meeting in Chicago.

At the meeting, I had a conversation with Dr Fatemeh Rajaii, an associate professor at Wilmer Eye Institute, Johns Hopkins, who discussed emerging therapies in TED from her presentation at the meeting.Let’s check out that conversation.

 My name is Fatemeh Rajaii. I'm an associate professor of ophthalmology and the Odd Fellows Rising Professor of Ophthalmology at the Wilmer Eye Institute at Johns Hopkins University, and I want to discuss the emerging therapies in thyroid eye disease.

Since the FDA approval of teprotumumab, there's been a lot of pharmaceutical interest in thyroid eye disease and developing new therapies. Currently, they’re broken down into 3 basic mechanisms. One is anti-IGF-1 receptor agents such as teprotumumab, with several others in development. Another is anti–IL-6 receptor agents, such as tocilizumab and others in development, like satralizumab and TOR-006; and then there are anti-FcRn receptor agents, which function by trying to reprogram the immune system by decreasing immunoglobulin half-life. Those agents include batoclimab and efgartigimod.

So, I think it's a really exciting time to be treating people with thyroid eye disease. I believe in the next 3 to 5 years, we’re going to have a lot more in our armamentarium to take care of these patients.

Thyroid Eye Disease (TED) Awareness Week, scheduled for November 18-24, 2024, aims to increase awareness of TED's symptoms, impact, and treatment options. Emerging therapies, including anti-IGF-1, anti-IL-6, and anti-FcRn receptor agents, are expanding treatment possibilities. TED symptoms range from bulging eyes to vision loss, with potential mental health impacts like depression and anxiety. Prevent Blindness offers resources to support TED patients, including educational materials and mental wellness support. These efforts aim to enhance understanding and care for TED patients and those affected by vision loss.

This Week in Ophthalmology is a weekly video series highlighting the latest news and articles featured on the Ophthalmology Times website.  

David J. Calkins, PhD

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