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Worldwide, 1.8 billion presbyopes exist, 826 million of whom are visually impaired because of inadequate vision correction.

Although most Americans have access to near vision correction, many are not satisfied with the experience of presbyopia—or their options for correcting it.

By far, the most common solution is OTC reading glasses, worn by 33 million Americans.

 As an optometrist, I consider them to offer low-level correction, typically of poor optical quality with significant visual and convenience tradeoffs. A 2018 market research survey conducted by Alcon found that presbyopes did not like them much, either. More than two-thirds (67%) said they would prefer to stop adjusting their lives around their vision and their need for reading glasses.

The onset of presbyopia carries many negative connotations. It is an early sign of aging that can pack an emotional punch. Patients find the sudden need to wear reading glasses or carry multiple pairs of glasses inconvenient and cosmetically unappealing.

Few presbyopes are offered contact lenses, however. A Gallup research poll in 2015 found that only 9% of adults over 40 years with vision correction were offered multifocal or monovision contact lenses when they complained about near vision problems.

 Lined bifocals or trifocals and progressive addition lens spectacles are more frequently offered despite interest from patients in reducing the need for spectacles.

Although my practice fits many multifocal contact lenses, barriers to success exist, particularly with emmetropes. I admit that I cringe when I have a 45-year-old patient who sees 20/15 uncorrected at distance and is “interested in contact lenses” because I know I have a slim chance of satisfying that patient with our current options. Fortunately, new technologies that have recently hit the market or are on the horizon could revolutionize the way ODs treat presbyopes in their practices.

One of the barriers to prescribing multifocal contact lenses has been the lack of options for patients with astigmatism. About half of all contact lens wearers have astigmatism,

 which becomes harder to mask with the onset of presbyopia. Dissatisfaction with vision is as much a factor as comfort when it comes to contact lens discontinuation among presbyopes.

In the past year, 2 toric multifocal contact lenses were introduced and should help to overcome that barrier: Ultra Multifocal for Astigmatism (Bausch + Lomb) and Biofinity Toric Multifocal (CooperVision). Both are daily-wear soft lenses with a monthly replacement schedule, and they are available in a wide range of parameters that allow ODs to fit most patients (

Although patients can have laser in situ keratomileusis (LASIK), photorefractive keratectomy, or small incision lenticule extraction monovision, there has never been a “no-brainer” surgical option—and the industry still lacks one for the younger presbyope.

For older presbyopes who already have lenticular changes, I am more likely now to recommend early lens surgery than I would have been a decade ago. Optometrists who were deterred by the lackluster results of first-generation presbyopia-correcting (PC) intraocular lenses (IOLs) such as Crystalens (Bausch + Lomb), ReZoom (AMO), and ReStor (Alcon) or even the second-generation multifocal IOLs, should look at the excellent results achieved with the latest PC IOLs.

These include the first trifocal, PanOptix (Alcon), and the first extended depth-of-focus (EDOF) lens, Tecnis Symfony (Johnson & Johnson Vision), in the United States. Both lenses overcame challenges with intermediate vision and night vision dissatisfaction that plagued earlier PC IOLs, providing high rates of patient satisfaction.

In the coming year, eye care practitioners will see a continuation of PC IOL innovation with the introduction of Johnson & Johnson Vision’s Tecnis Synergy, an EDOF-multifocal hybrid that is expected to provide better near vision, and Alcon’s low-add Vivity EDOF lens, which was just launched. A small-aperture IOL from AcuFocus in the pipeline has also shown impressive results

 and may be helpful for patients with irregular corneas.

PC IOL technology has reached a level that makes me confident in encouraging patients with cataract and those who are closer to needing cataract surgery to make this choice. But a clear lensectomy is still a big jump for a 45-year-old with residual accommodation who is frustrated with near vision. As far as PC IOLs have come, they still would not be my choice for most patients under age 60 years.

A number of pharmacological treatments for presbyopia are in phase 2 or 3 US clinical trials (

), with several expected to become available within the next year. The potential for a topical treatment is very exciting. The drops in development are primarily miotic agents. These drugs, including pilocarpine, carbachol, and aceclidine, have well-established mechanisms of action and safety records. They increase depth-of-focus through the pinhole effect and activate the ciliary body for some accommodative effect, as well.

Some pupil-modulating agents, such as Allergan’s pilocarpine product (AGN-190584), are expected to be single-agent drops, whereas others combine the miotic agent with other drugs to mitigate adverse effects. Visus Therapeutics, for example, has been investigating a fixed combination of carbachol and brimonidine, which has the potential to prolong the pinhole effect to 8 hours, reduce the brow aches and headaches that have been associated with cholinergic agonists in the past, and whiten the eye at the same time.

The great news is that pupil-modulating drops will likely be low risk and reversible, making them an easy option for patients to try. My expectation is that optometrists will be able to prescribe and, in some states, dispense pupil-modulating drops, which is a tremendous opportunity. Many patients who will be good candidates for these drops—emerging presbyopes in their 40s, post- LASIK emmetropes, those who cannot wear contact lenses or could not adapt to progressive lenses, and even pseudophakes who are not happy with reading glasses. Until ODs have more clinical data from the ongoing studies, exactly how presbyopia drops will fit into the armamentarium is difficult to predict, but I can envision the market being very broad.

Another category of topical therapies under development, most notably by Novartis, has the potential to alter crystalline lens proteins to soften the lens or prevent the effects of aging. Although these drops are still in the pipeline, investigators hope they will delay the effects of presbyopia and cataract.

As these innovative new drops come to market, ODs will need to learn more about their mechanisms of action, duration, and adverse effect profiles. ODs will also need to try them with their own patients to discover variability in patient response and determine how to counsel patients on drop frequency and administration.

Perhaps most exciting is that presbyopia drops have the potential to bring a whole new patient segment into optometric offices—emmetropic adults who haven’t had an eye exam in years (maybe never) because they didn’t need vision correction or were able to get by with drugstore readers. Not only is addressing this patient population a great practice growth opportunity, it is also a public health opportunity. Those emmetropes might have untreated dry eye, glaucoma, or macular degeneration. Their eyes may provide a clue to undiagnosed systemic conditions, such as diabetes or hypertension. Losing near vision may be what motivates emmetropic individuals to come into optometric offices, but presbyopia treatment is just the start of the care ODs can provide.

Corneal collagen cross-linking is now accepted as the standard treatment for progressive keratoconus and post-refractive ectasia. Outside the United States, cross-linking has been investigated for a range of applications, including myopia control, corneal stabilization prior to corneal refractive surgery, and presbyopia correction. Photorefractive intrastromal cross-linking for presbyopia is a monocular treatment in which a ring of tissue in the midperiphery of the cornea is cross-linked to produce central steepening for near vision.

 The procedure, which is performed with the Mosaic system (Glaukos), has been studied and performed commercially in Europe and Asia but will likely not be available for some time in the United States.

The future for presbyopia care is bright. Optometrists have new multifocal contact lenses and presbyopia-correcting IOLs, as well as multiple pharmacological agents in the pipeline for this previously underserved affected patient population. I believe eye care is on the cusp of a renaissance in presbyopia management, so this is a great time to start talking with patients about new and emerging developments.

Fricke TR, Tahhan N, Resnikoff S, et al. Global prevalence of presbyopia and vision impairment from uncorrected presbyopia; systematic review, meta-analysis, and modelling. 

. 2018;125(10):1492-1449. doi:10.1016/j. ophtha.2018.04.013

Organizational overview. The Vision Council. Accessed February 28 2021. https://www.thevisioncouncil.org/sites/ default/files/TVC_OrgOverview_sheet_0419.pdf

Presby-what? new Alcon surveys show patients have fuzzy understanding of presbyopia; eye care professionals agree. News release. Alcon. April 5, 2019. Accessed February 11, 2021. https://www.alcon.com/media-release/presby-what-new-alcon-surveys-show-patients-have-fuzzy-understanding-presbyopia-eye

/Bausch + Lomb. Capturing the presbyopic opportunity. 2016. Accessed December 22, 2020. https://www.bausch.com/Portals/77/-/m/BL/ United%20States/Files/Downloads/ECP/Vision%20Care/ BL-Multifocal-Supplement.pdf?ver=2016-07-28-103547-817

Young G, Sulley A, Hunt C. Prevalence of astigmatism in relation to soft contact lens fitting. 

2011;37(1):20-25. doi:10.1097/ICL.0b013e3182048fb9

Rueff EM, Varghese RJ, Brack TM, Downard DE, Bailey MD. A survey of presbyopic contact lens wearers in a university setting. 

2016;93(8):848-854. doi:10.1097/ OPX.0000000000000881

Pedrotti E, Carones F, Talli P, et al. Comparative analysis of objective and subjective outcomes of two different intraocular lenses: trifocal and extended range of vision. 

2020;5(1):e000497. doi:10.1136/ bmjophth-2020-000497

Choi M, Im CY, Lee JK, Kim HI, Park HS, Kim TI. Visual outcomes after bilateral implantation of an extended depth of focus intraocular lens: a multicenter study. 

2020;34(6):439-445. doi:10.3341/ kjo.2020.0042

Kohnen T, Herzog M, Hemkeppler E, et al. Visual performance of a quadrifocal (trifocal) intraocular lens following removal of the crystalline lens. 

2017;184:52-62. doi:10.1016/j.ajo.2017.09.016

. Ang RE. Visual performance of a small-aperture intraocular lens: first comparison of results after contralateral and bilateral implantation. 

2020;36(1):12-19. doi:10.3928/1 081597X-20191114-01

. Abdelkader A, Kaufman HE. Clinical outcomes of combined versus separate carbachol and brimonidine drops in correcting presbyopia. 

2016;3:31. doi:10.1186/ s40662-016-0065-3

Becker-Shaffer’s Diagnosis and Therapy of the Glaucomas

. Kanellopoulos AJ, Asimellis G. Presbyopic PiXL cross-linking. 

2015;3:1-8. doi:10.1007/ s40135-014-0060-6

Articles

New technology may be able to help ODs’ most challenging patient segment

The coming presbyopia revolution

Biologic medications have long since been a group of high-tech chemicals known to improve and save lives. Previous generations included vaccines, insulin, and blood components, and the newer armamentarium features chemicals that treat cancers, autoimmune disease, wet age-related macular degeneration, and thyroid eye disease.

Now that biologics have been approved for certain ophthalmic diseases, conditions, and indications (

), every optometric physician needs to have a basic understanding of related nomenclature and pharmacology to help improve patient care outcomes.

Biologic chemicals and traditional drugs (ie, small molecule drugs) are different in several ways. Most drugs and chemicals (nonbiologics) have a known structure that is easily synthesized and easily repeated (think brand-name and generic drugs), are small in size (compared with biologics), and may be synthetic. Additionally, most non-biologic drugs are not overly sensitive to percussion or movement and reasonable temperature changes during shipping and storage.

Biologics are engineered from a variety of sources, including animals, microorganisms, and humans. These agents are not easily synthesized or repeatable because they are complex, large structures that are inherently unstable with heat and percussive movement, and they tend to be easily contaminated with microorganisms during manufacturing.

Lastly, biologic medications are more expensive compared with their small, chemical, synthetic brethren.

Why, then, are so many biologics now available, with many more in the pipeline? The answer is simple: Biologics have the ability to treat diseases and conditions better than some traditional choices, and they also offer treatments or cures for diseases and conditions for which no other treatment options exist.

Biosimilar drugs are popping up everywhere and usually in tandem with biologics. In short, biosimilars are the closest thing to a “generic” biologic that practitioners will ever see because a true generic biologic is impossible to make. The term 

denotes that the agent has proved to be highly similar to a corresponding biologic (originator, innovator, reference product) with no meaningful differences in pharmacology and pharmacotherapeutics, including purity, safety, and efficacy.

Although there is no clinically meaningful difference between a biologic and a biosimilar that has been made to be “highly similar,” they are not automatically interchangeable because production of a biologic, a complex molecule, is proprietary.

So, although the pharmaceutical company that manufactured the biologic owns the proprietary production and manufacturing of the drug, it does not own the actual structure. As such, most of the manufacturing time for a biosimilar is spent on duplicating the production of the innovator product with differences in clinically inactive components, whereas the pharmaceutical company that discovered the innovator product spends the majority of its time researching efficacy, safety, and pharmacokinetics.

This is different from the production process of a typical generic medication for a small molecule drug because the generic has the same active ingredients of a brand-name drug, and the manufacturer must prove the agent’s bioequivalence to the brand-name drug before it can receive FDA approval. Note that a biosimilar drug will never be exactly the same as the biologic drug, but it will be highly similar.

So, why use a biosimilar drug rather than a biologic drug? Cost. Biosimilars are generally much less expensive.

The nomenclature of biologic and biosimilar medications will begin to make logical sense once a practitioner learns a few basic rules and patterns. Monoclonal antibody (mAb) biologic names follow rules and patterns established by the World Health Organization’s International Nonproprietary Name (INN) Expert Group.

The INN assigns the nonproprietary (generic or proper) names to biologics and other medications and therapies that are recognized worldwide as public property. For instance, substances that are considered to be similar in their pharmacology have a prefix, 2 common “stems” (the first indicating the mAb target; the second, the mAb source species), ending in 

). This helps medical professionals and investigators recognize which agents have similar pharmacology.

Additionally, in 2017, the FDA determined that all new biologics should contain a unique (and generally random) 4-letter suffix that further identifies and differentiates each drug.

 This allows for improved pharmacovigilance where medical professionals and manufacturers can track every agent, both biologics and biosimilars.

Cenegermin-bkbj (Oxervate) offers an example of this suffix. If another company makes a biosimilar product in the future, the biosimilar will be called “cenegermin” but will have a different 4-letter suffix.

The list of biologics for targeting ocular diseases and conditions continues to grow rapidly, and biosimilar products will likely follow over the next few years. Practitioners should keep up with this exciting trend in ocular therapeutics as part of their efforts to improve patient care outcomes.

What are “biologics” questions and answers. US FDA. Updated February 6, 2018. Accessed December 9, 2020. https://www.fda.gov/about-fda/center-biologics-evaluation-and-research-cber/what-are-biologics-questions-and-answers

Joseph M, Trinh HM, Cholkar K, Pal D, Mitra AK. Recent perspectives on the delivery of biologics to back of the eye. 

. 2017;14(5):631-645. doi:10.1080/1742 5247.2016.1227783

Biological product definitions. FDA. Accessed March 8, 2021. https://www.fda.gov/downloads/ Drugs/DevelopmentApprovalProcess/ HowDrugsareDevelopedandApproved/ApprovalApplications/ TherapeuticBiologicApplications/Biosimilars/UCM581282.pdf

Posarelli C, Arapi I, Figus M, Neri P. Biologic agents in inflammatory eye disease. 

Eylea. Prescribing information. Regeneron Pharmaceuticals; 2019. Accessed March 8, 2021. https://www.accessdata.fda. gov/drugsatfda_docs/label/2019/125387s061lbl.pdf

Balaratnasingam C, Dhrami-Gavazi E, McCann J, Ghadiali Q, Freund KB. Aflibercept: a review of its use in the treatment of choroidal neovascularization due to age-related macular degeneration. 

. 2015;9:2355-2371. doi: 10.2147/OPTH.S80040

Lucentis. Prescribing information. Genentech Inc; 2014. Accessed March 8, 2021. https://www.accessdata.fda.gov/ drugsatfda_docs/label/2014/125156s105lbl.pdf

Macugen. Prescribing information. Bausch + Lomb; 2016. Accessed March 8, 2021. https://www.bausch. com/Portals/77/-/m/BL/United%20States/Files/ Package%20Inserts/Pharma/macugen-package-insert. pdf?ver=2017-02-14-083844-843

Beovu. Prescribing information. Novartis Pharmaceuticals Corp; 2020. Accessed March 8, 2021. https://www.novartis.us/ sites/www.novartis.us/files/beovu.pdf

. Oxervate. Prescribing information. Dompé US Inc; 2018. Accessed March 8, 2021. https://www.accessdata.fda.gov/ drugsatfda_docs/label/2018/761094s000lbl.pdf

. Humira. Prescribing information. AbbVie Inc; 2021. Accessed March 8, 2021. https://www.rxabbvie.com/pdf/ humira.pdf

. Actemra. Prescribing information. Genentech Inc; 2021. Accessed March 8, 2021. https://www.gene.com/download/ pdf/actemra_prescribing.pdf

. Tepezza. Prescribing information. Horizon Therapeutics USA Inc; 2020. Accessed March 8, 2021. https://www.hzndocs. com/TEPEZZA-Prescribing-Information.pdf

. Sharma A, Kumar N, Kuppermann BD, Bandello F, Loewenstein A. Understanding biosimilars and its regulatory aspects across the globe: an ophthalmology perspective. 

2020;104(1):2-7. doi:10.1136/ bjophthalmol-2019-314443

. Sharma A, Reddy P, Kuppermann BD, Bandello F, Loewenstein A. Biosimilars in ophthalmology: “is there a big change on the horizon?” 

. 2018;12:2137-2143. doi:10.2147/OPTH.S180393

. Azevedo V, Hassett B, Fonseca JE, Atsumi T, Coindreau J, Jacobs I, et al. Differentiating biosimilarity and comparability in biotherapeutics. 

2016;35(12):2877-2886. doi: 10.1007/s10067-016-3427-2

. Biosimilars. FDA. Updated February 3, 2020. Accessed March 8, 2021. https://www.fda.gov/drugs/therapeutic-biologics-applications-bla/biosimilars

. Pasina L, Casadei G, Nobili A. Biological agents and biosimilars: essential information for the internist. 

. 2016;33:28-35. doi:10.1016/j.ejim.2016.06.005

. Declerck P, Farouk-Rezk M, Rudd PM. Biosimilarity versus manufacturing change: two distinct concepts. 

2016;33(2):261-268. doi:10.1007/s11095-015-1790-3

. Mallbris L, Davies J, Glasebrook A, Tang Y, Glaesner W, Nickoloff BJ. Molecular insights into fully human and humanized monoclonal antibodies: what are the differences and should dermatologists care? 

. World Health Organization. International Nonproprietary Names (INN) for biological and biotechnological substances (a review). 2016. Accessed December 11, 2020. https://www.who. int/medicines/services/inn/BioReview2016.pdf

Guidance on the use of International Nonproprietary Names (INNs) for pharmaceutical substances. 2017. World Health Organization. Accessed December 11, 2020. www.who.int/ medicines/services/inn/innguidance/en/

. Nonproprietary naming of biological products: update. FDA. March 2019. Accessed March 8, 2021. https://www.fda.gov/ media/121316/download

This drug category is rapidly growing in the ophthalmic space, with more options in the pipeline

Biologic medications: The basics that every OD should know

With 2020 behind us but hardly forgotten, coronavirus disease 2019 (COVID-19) remains dominant in local, state, and national headlines. New cases of COVID-19 infections and death rates attributed to the virus set records in parts of the United States in the first quarter of 2021.

As the health care system continues to struggle with caseloads and managing this pandemic, the economy seeks to rebound as quickly and safely as possible. Many sectors have taken huge financial losses, yet most optometry practices have survived, albeit with lingering personal protective equipment costs, enhanced cleaning procedures, occasional closures due to COVID-19 cases and/or government edicts, facility and procedural modifications, altered appointment schedules, increased telemedicine usage, and other pandemic-induced adjustments. How close we are to controlling the pandemic and returning to “normal” now seems to hinge on the rollout of COVID-19 vaccines.

In addition to the final COVID-19 relief package at the end of last year (“What ODs Need to Know About the New COVID Relief Package,” April 2020), 2020 also gave us literal “shots in the arm” on its way out with the FDA’s December 2020 emergency use authorization (EUA) for the first 2 COVID-19 vaccines by Pfizer-BioNTech and Moderna–National Institute of Allergy and Infectious Diseases, respectively. Both represent a novel type of vaccine using messenger RNA to produce immunity and require 2 inoculations separated by several weeks.

Other vaccines showed promising early results by the start of 2021, including those from Oxford-AstraZeneca (a 2-dose vaccine approved and rolled out in the United Kingdom in late 2020 and in India in early 2021) and Johnson & Johnson, both of which use viral vectors to induce immunity. Novavax and others have vaccines in various stages of development, some of which represent traditional protein-based vaccines and require only a single dose.

 However, as of the writing of this article, no vaccines to prevent COVID-19 had been FDA approved (ie, none have yet completed the approval process). Instead, we have only these with EUA, indicating the potential benefits outweigh the potential risks.

As the first COVID-19 vaccine approvals loomed and subsequent rollouts began in late 2020, the Advisory Committee on Immunization Practices (ACIP) of the Centers for Disease Control and Prevention (CDC) released recommended guidelines for COVID-19 vaccination priority. ACIP’s recommendations were accepted by the CDC and defined “health care personnel” as “paid and unpaid persons serving in health care settings who have the potential for direct or indirect exposure to patients or infectious material.” Guidelines dictate these persons should be prioritized for the COVID-19 vaccine.

ODs serve in inpatient and outpatient health care settings with the potential for direct and indirect exposure to patients or infectious material, so ODs and their staff members are prioritized in the earliest phase 1a timetable. However, state health agencies are not obligated to follow ACIP’s recommendations, and many—appropriately—prioritized health care workers directly caring for patients with COVID- 19 in hospital settings first, as well as vulnerable residents of long-term care facilities. After these 2 groups, most health care providers in ambulatory and outpatient clinics are next in line.

Data show how vaccines protect against infection:

Pfizer’s vaccine is 95% effective at preventing COVID-19.

Moderna’s vaccine is 94.1% effective at preventing symptomatic COVID-19.

AstraZeneca’s vaccine was found to be 70.4% effective in early studies.

An individual naturally infected with the virus appears unlikely to become reinfected in the 90 days after initial infection, according to available data,

 but it is too early to know how long the vaccines provide immunity. Vaccines appear to reach maximum efficacy 1 to 2 weeks after the second dose.

Both vaccines appear to be highly effective at preventing symptomatic COVID-19, but it is too early to conclude whether they reduce transmission of the virus.5 It is anticipated they will be effective against mutations of the virus.

Although the FDA’s EUA means the potential benefits of these vaccines outweigh their potential risks, adverse events exist. Allergy to any vaccine component is possible, but aside from a rare severe allergic reaction, no concerning safety events were reported, with local reactions (ie, pain, edema, erythema) at the injection site being mild. After the second dose of the vaccine, about half of patients in one study experienced moderate-to-severe adverse events (eg, fatigue, muscle aches, joint pain, headache), which resolved in most patients within 2 days.

FDA-approved COVID-19 vaccine doses purchased with taxpayer dollars are available to US citizens at no cost; however, health care personnel administering them can charge an administration fee for providing the inoculation. This fee is typically covered by the patient’s public or private medical insurance or, if a patient is uninsured, by the Health Resources and Services Administration’s Provider Relief Fund.

 In some states, ODs are administering vaccinations and are eligible for reimbursement.

Among providers in medical specialties, those in ophthalmology (and by extension, optometry, because ODs provide the same primary eye care, use the same equipment, and are in the same proximity to patients) have been found to be the third most at risk for contracting COVID-19, behind anesthesiology and emergency medicine providers.

 Thus, eye care providers and their staffs are at greater risk of contracting and unwittingly transmitting COVID-19.

Further, the Health Policy Institute of the American Optometric Association provides data indicating a 300% increase in ODs reporting that they or a staff member received a diagnosis or tested positive for COVID-19 during a 3-month period from June to September, 2020.

 These data were collected prior to the most recent record-setting surge in cases.

Vaccines can accelerate “herd” immunity against COVID-19. Although the percentage of the population who needs to be vaccinated to achieve that status is still unclear, certainly the more people who get vaccinated, the faster this immunity will happen.

The US Equal Employment Opportunity Commis(EEOC) allows employers to mandate vaccinations for employees; however, a mandate can get complicated for disabled employees, those who claim a sincerely held religious practice or belief prohibiting vaccinations, or those with preexisting health conditions for which a vaccine may be contraindicated.

The EEOC states: “If an employee cannot get vaccinated for COVID-19 because of a disability or sincerely held religious belief, practice, or observance, and there is no reasonable accommodation possible, then it would be lawful for the employer to exclude the employee from the workplace. This does not mean the employer may automatically terminate the worker. Employers will need to determine if any other rights apply under the EEO laws or other federal, state, and local authorities.”

ODs who mandate that staff receive COVID-19 vaccination should develop a written policy and review it with them, recognizing they may need to make “reasonable accommodations” (eg, allowing remote work if the job description permits) unless there is a “significant risk of substantial harm to the health or safety of the individual or others that cannot be eliminated or reduced by reasonable accommodation.”

Specifically, an employer must individually assess “whether a direct threat exists: the duration of the risk; the nature and severity of the potential harm; the likelihood that the potential harm will occur; and the imminence of the potential harm” before terminating an employee for not receiving a vaccination.

 Consult a labor attorney for additional guidance before making a final decision.

The choice to get vaccinated is personal, at times complicated by institutional distrust, lack of knowledge, misinformation, and fear. To make the best decision possible, ODs should educate staff about these vaccines and their implications for personal and public health, then consider all factors, including relative risk of contracting COVID-19 and possible results if so; the potential health impact on coworkers, patients, friends, and family members; and the safety data and guidance published by the FDA, CDC, and other entities. If desired, practitioners can give staff incentive by allowing them to get vaccinated during working hours and offering to cover out-of-pocket costs.

ODs and their staffs continue to play a crucial role in caring for patients during this unprecedented public health emergency. In so doing, they have a risk of contracting COVID-19 despite mitigation efforts, and vaccines offer an opportunity to help protect one another while accelerating a return to normal.

Zimmer C, Corum J, Wee SL. Coronavirus vaccine tracker. 

. Updated March 16, 2021. Accessed March 16, 2021. https://www. nytimes.com/interactive/2020/science/coronavirus-vaccine-tracker.html

Landscape of novel coronavirus candidate vaccine development worldwide. World Health Organization. March 12, 2021. Accessed March 16, 2021. https://www.who.int/publications/m/item/draft-landscape-of-covid-19-candidate-vaccines

Dooling K, McClung N, Chamberland M, et al. The Advisory Committee on Immunization Practices’ interim recommendation for allocating initial supplies of COVID-19 vaccine—United States, 2020. 

2020;69:1857-1859. doi:10.15585/mmwr.mm6949e1

Pfizer-BioNTech COVID-19 vaccine frequently asked questions. FDA. January 28, 2021. Accessed March 16, 2021. https://www.fda.gov/ emergency-preparedness-and-response/mcm-legal-regulatory-and-policy-framework/pfizer-biontech-covid-19-vaccine-frequently-asked-questions

Peer-reviewed report on Moderna COVID-19 vaccine publishes. National Institutes of Health. December 30, 2020. Accessed March 16, 2021. https://www.nih.gov/news-events/news-releases/peer-reviewed-report-moderna-covid-19-vaccine-publishes

Knoll MD, Wonodi C. Oxford-AstraZeneca COVID-19 vaccine efficacy. 

. 2021;397(10269):72-74. doi:10.1016/S0140- 6736(20)32623-4

Frequently asked questions about COVID-19 vaccination. Centers for Disease Control and Prevention. Updated March 12, 2021. Accessed March 16, 2021. https://www.cdc.gov/coronavirus/2019- ncov/vaccines/faq.html

Wise N, Moriarty C. The new COVID-19 vaccine: answers to all the hard questions. Yale Medicine. December 18, 2020. Accessed March 16, 2021. https://www.yalemedicine.org/news/covid-19-vaccine

Eldred SM. Which specialties are at highest risk for contracting COVID-19? Medscape. May 14, 2020. Accessed March 16, 2021. https://www.medscape.com/viewarticle/930553

. CDC vaccine prioritization. American Optometric Association. December 3, 2020. Accessed March 16, 2021. https://www.aoa.org/ AOA/Documents/Advocacy/Letters/CDC-Vaccine-Prioritzation.pdf

. What you should know about COVID-19 and the ADA, the Rehabilitation Act, and other EEO laws. US Equal Employment Opportunity Commission. Updated December 16, 2020. Accessed March 16, 2021. https://www.eeoc.gov/wysk/what-you-should-know-about-covid-19-and-ada-rehabilitation-act-and-other-eeo-laws

Explore the risks and benefits of different approaches to virus vaccination

Should ODs get a COVID-19 vaccine and require staff to get vaccinated?

Scleral lenses have become increasingly accessible and popular and prescribed more often in recent years. Indications for these lenses include various types of ocular surface disease and irregular corneas.

As scleral lens fitting has become more widespread over the past decade, practitioners have also come to realize different challenges and fitting limitations.

Fitting a scleral lens is a multifaceted endeavor, with the desired outcome to improve a patient’s condition, be that improving vision or decreasing ocular discomfort. Although the benefits of scleral lens wear are clear, fitting end points may vary depending on practitioner preference and lens design utilized. Additionally, whereas some complications are relatively easy to recognize, some may fall into unclear territory.

Contact lenses for monocular patients are generally avoided because of the risk of complications that could lead to vision loss in an individual with only 1 eye.

 However, in some patients with irregular corneas or dry eyes, glasses may not be an option for optimal vision correction. Specialty contact lenses, including scleral lenses, may provide significantly improved vision and comfort and can be prescribed with caution. Extra care should be taken to ensure proper lens and solution use and overall hygiene. Polycarbonate lenses in spectacles should be recommended for full-time wear with or without contact lenses, and practitioners should see patients at more frequent intervals to ensure stable eye health.

The concern of hypoxia in ocular structures from scleral lens wear has been discussed in the past with inconclusive evidence regarding hypoxia’s effect on the cornea. Some theoretical models suggest that certain central clearance limits must be followed for the cornea to thrive,

 whereas others present clinical evidence that shows no significant corneal thickness change in a clinical setting.

 the resolution of acute, aggressive corneal neovascularization with associated haze from a previous hybrid contact lens wearer was achieved by fitting a scleral lens with central clearance in excess of 500 μm. This case demonstrates that a high central clearance itself does not automatically mean that the scleral lens fit is poor. 

show a similar resolution of dense corneal haze after several years of wear. Rather, other variables should be considered as well, because all parameters of a scleral contact lens contribute to the overall system of the fit. These include the material, the diameter, and the peripheral haptic alignment of the lens.

For instance, a larger diameter may distribute the weight of the scleral lens over a larger area, resulting in less conjunctival compression, and a looser fit could indirectly decrease hypoxia by encouraging more tear exchange. In addition, careful observation must be given to scleral lens fits for corneal grafts because these postsurgical corneas may be more susceptible to endothelial and hypoxic complications. Although high clearance may not necessarily induce corneal edema, lens clearance is 1 variable that can be adjusted if hypoxia becomes a concern.

Conjunctival prolapse is a clinical finding that many observe with scleral lens fits and is often more prevalent with increasing age. This occurs when loose conjunctival tissue adjacent to the limbus is pulled within the fluid chamber of the scleral lens where there is limbal clearance. The spherical optic zone of a lens on an elliptical cornea that is wider horizontally than vertically results in more limbal clearance superiorly and inferiorly.

 As such, our experience is that conjunctival prolapse appears most often in the inferior quadrant.

Conjunctival prolapse can be treated by decreasing the limbal clearance so there is limited room for the conjunctiva to migrate. This might be considered for patients with limbal stem cell deficiency or a history of inflammation because the conjunctiva may become adherent to the peripheral cornea if left untreated. In other cases, however, the prolapse may not need to be addressed.

shows an example of a patient with dry eye syndrome who was originally fit in 2009 with scleral lenses. The conjunctiva that is pulled into the fluid chamber returns to its normal configuration upon lens removal. Photos of both eyes 10 years later show no complications of the prolapse, including no active or progressive neovascularization on the cornea where there is prolapse (

Irregular conjunctiva following glaucoma procedures

Treatment of patients wearing scleral lenses with advanced glaucoma requiring tube surgery can be particularly challenging. A tube that is inserted into the anterior chamber to relieve high intraocular pressure often presents an obstacle for scleral lens alignment (

). The elevation on the sclera from the tube is covered with a thin layer of conjunctiva, and pressure from a scleral lens can stain or compromise the area of contact. A worst-case scenario is conjunctival erosion over the tube, which would lead to an open-eye scenario in which the anterior chamber could be exposed through the breakdown in the conjunctiva.

Fortunately, recent technological advances such as custom channels within the lens haptics (

), image-guided fitting, and impression molding offer multiple ways to better align a scleral lens around an elevated tube. It is critical, however, to closely monitor the fit over the tube for staining that may result from lens wear. Consistent photo documentation of the lack of staining over the tube before and after lens wear should be practiced to support the safety of lens wear (

Extended wear for persistent epithelial defects

Corneal epithelial defects are an unwelcome finding, but a persistent epithelial defect (PED; 

), defined as a corneal epithelial defect that does not close or heal after 2 weeks with standard supportive therapy,

 is an even bigger obstacle. Management may include use of aggressive topical lubrication and ointments, bandage soft contact lenses, punctal plugs, prophylactic topical antibiotics, and autologous serum tears, as well as tarsorrhaphy, amniotic membrane grafting, and/or cenegermin-bkbj (Oxervate; Dompé) use.

An additional off-label therapy includes the use of scleral lenses worn in an extended-wear fashion. This protocol has been shown to be effective in healing PEDs when traditional therapies have failed.

 Although overnight scleral lens wear is traditionally not advised because of the risk of microbial keratitis,

 scleral lenses have been used in this manner because of the distinctive hydrating and protective environment they create for the cornea. Strict hygiene protocols and frequent follow-up are essential to ensure proper healing of the eye.

Scleral lens fitting challenges are inevitable. In addition to the more well-known contact lens-related complications such as microbial keratitis and inflammation from lens overwear, practitioners need to be aware of potential hypoxic complications in the cornea and know how to navigate conjunctival irregularities.

Although a fit may look good upon dispensing in office, all fits need to be monitored over time. Because scleral lenses are often utilized in patients with compromised corneas, carefully monitoring the eyes is critical. The ocular surface, when exposed to different environments, is not always predictable. The conjunctival and scleral tissues, which bear the weight of the lens, vary in structure with age and disease presentation.

 Settling of the lens over time must be watched to avoid harmful corneal touch.

When complications are encountered, practitioners may need to make adjustments to the lens design. They must also be prepared to discontinue a scleral lens fitting or consider a different contact lens modality if the current scleral lens is causing any harm to the eye.

Test your skills on scleral lens fitting! Click HERE to take this article's quiz

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Closely monitor patient over time for continued corneal health and good fit

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