Dr Marc D. de Smet

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If we have learned anything in 2020, it is this: you do not want to contract COVID-19. It is not clear if post-infection immunity to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus lasts longer than 4–6 months.

 It is also increasingly apparent that many infected patients who suffered only mild symptoms have actually experienced considerable organ damage – not just to their lungs,

Simple public health measures that should be effective in reducing SARS-CoV-2 transmission, such as wearing face masks in busy public areas including shops and public transport, are facing resistance. It may be that the course of the current COVID-19 crisis mirrors the 1918 influenza pandemic:

 an initial devastating wave of cases soon followed by a far larger second wave, and then a disturbingly long tail. The best form of disaster management is to hope for the best but prepare for the worst. So how does this translate into the running of a medical retina service?

Most patients attending such a service have either age-related or diabetic eye disease, both of which are risk factors for severe disease and death from COVID-19.

 Some of these patients may be residents in residential care homes, which have been hotbeds of disease activity during the last spike in cases.

This means there is a very thin tightrope to be walked: the ophthalmologist needs to see the patients as frequently as possible to maintain these patients’ vision as best as possible under these circumstances, but as infrequently as possible to minimise the risk of SARS-CoV-2 infection. How do we go about achieving this?

Triage, sanitiser and personal protective equipment

It starts well before the clinic. At our practice, patients are sent questionnaires 48 hours before they arrive, asking whether they have been in contact with a person with COVID-19, have travelled to a region with a high prevalence of COVID-19 and whether they are experiencing any COVID-19-related symptoms.

If patients are likely to have COVID-19 based on their answers, then we must decide whether seeing them in the next few days is essential or can wait for a 14 days’ ‘office isolation’ period. We also need to decide whether to refer them to a facility that specifically deals with people with COVID-19, or whether we can issue them with an FFP2 mask at their arrival, ask office personnel to wear appropriate personal protective equipment (gown, FFP2 mask, protective eyewear) and see these patients at the end of the day.

Hand sanitiser, face masks and social distancing are key weapons in stopping the spread of the virus: all patients are asked to sanitise and wear a mask, and the layout of the waiting area has changed, with every second seat removed to stop patients from sitting together and ensure a 1.5-m distance is maintained.

We also keep as many doors and windows open as possible to maximise the flow of fresh air in the building with the aim of reducing the concentration of any SARS-CoV-2 fomites that may be present (and to minimise the repeated touching of door handles). In larger clinics or hospitals, having an outside tent can also be used to perform screening procedures while insuring adequate ventilation.

Patients’ friends and family are forbidden from accompanying them into the clinic to minimise the potential for SARS-CoV-2 exposure to both the other patients and clinic staff. As the risk of contagion waxes and wanes, this requirement can be adjusted based on the local risk, as it is seen as a burden by many patients and their families.

The number of people in the waiting room is limited to three groups of two people.We also perform a form of scheduling triage: patients with the highest risk of severe COVID-19-related disease and death—such as those with both hypertension and type 1 diabetes—are seen in the first few appointments of the day, based on the assumption that fewer potentially infected people would have been in the clinic before them, and fomites do not survive on surfaces and in the air for a prolonged period of time.

Pushing the treatment interval to the max

The key to keeping treatment standards as high as possible under such difficult circumstances is chart review. If patient care can be managed remotely with a telephone call, this is better than having them come into the clinic.

When it comes to patients receiving anti-vascular endothelial growth factor (anti-VEGF) agents for treating either neovascular age-related macular degeneration (AMD) or diabetic macular oedema (DMO), the charts of patients seen regularly should be reviewed, to see if a treat-and-extend (T&E) regimen has really been pushed to the maximum. If it is feasible for a patient to visit the clinic every 3 months, we would try and push the treatment interval to this length of time or longer.

One also needs to prepare oneself for some difficult choices: as if the COVID-19 situation is not dire enough, the fact is that some patients may have to lose vision – a decision that might be made easier if the patient is losing vision in one eye and not the other, or harder when the patient has only one remaining ‘good’ eye. When it comes to ensuring patients retain their vision, the biggest risk of failure is loss to follow-up: despite everything else, ophthalmologists need to keep in contact with their patients to ensure that they do attend these (now very) critical clinic visits for treatment that really does have to be administered in a timely manner.

It would appear to be the case that large outbreaks take around 2–3 months to control. For those with DMO, especially patients who are pseudophakic, use of longer-acting steroid therapy such as Ozurdex (dexamethasone intravitreal implant, Allergan) is seriously worth considering. When it comes to phakic patients, what we have been seeing with uveitis patients is that cataracts only really start to develop after the injection of the third implant.

In countries which are still in their first wave of infections or possibly a continuous surge as in the United States, longer-acting agents are even more important in reducing the number of patient visits to the clinic. The decision to use steroid treatment is one that requires careful thought because of the potential risks of increased intraocular pressure and cataract development.

It may be less appropriate to administer steroids to younger people, but in our opinion, the ones that are really at high risk are the older individuals who have diabetes, hypertension and are obese. In the current context, it is probably better to put them on Ozurdex, perhaps with prophylactic anti-glaucoma drops if there is a known or suspected ocular hypertension response to steroids. These patients present to the clinic less frequently and if a cataract develops, it can be dealt with once the much-anticipated ‘second wave’ of COVID-19 cases has subsided.

Why a slit lamp exam might be riskier than a surgical procedure

Cataract surgery, perhaps counter-intuitively, is a procedure that should have a low risk of SARS-CoV-2 transmission. When performing this procedure, we test all patients for COVID-19 2–3 days before surgery; all COVID-19-negative individuals then receive the surgery.

There is a theoretical risk that the patient may have been infected in the meantime, but in the first few days, they themselves are unlikely to transmit the virus. The patient wears a mask before, during and after the procedure; almost all cataract procedures are performed under local anaesthesia (so no intubation is required); just before starting the surgery, they can be asked to drop the mask so that they can be given oxygen and then they are covered with the sterile drape with a seal around the eyes.

In fact, the risk during surgery versus slit lamp examinations is lower than we perhaps tend to think. There is certainly less risk associated with performing OCT imaging than there is with a slit lamp exam 30 cm from the patient (even if there is a layer of Perspex screening around the slit lamp); with the OCT, being sat in front of the computer, the ophthalmologist and their technician are around 1.5 m further away from the patient and are not sitting directly in front of them either.

One other noteworthy point is that masks can steam up lenses on diagnostic instruments, and this is more likely to occur in warm and humid offices. The difference between a cold and dry day, and a hot and humid day, made a three-line difference in patients’ performance when performing a refraction with trial lenses.

If the COVID-19 pandemic worsens dramatically and is associated with a long tail, then ‘what good looks like’ is going to involve assessment and treatment modalities that identify patients in need of treatment, and extending the period between patient visits to the clinic during these critical 2–3 month periods. As things currently stand, these treatments are limited to longer-acting steroid implants and maximal T&E protocols with anti-VEGF drugs.

In the near future, it is clear that some aspects of the clinic visit could be replaced by telemedicine, such as certain aspects of the regular consultation being performed over the telephone, Snellen visual acuity assessments being performed via smartphone apps and ocular surface examinations over video consultations. However, these are clearly insufficient for monitoring the status of the retina.

What we need is home OCT testing that patients can use to generate images which he/she then shares with the retina specialist for assessment and treatment decision-making. This would dramatically reduce the number of patient visits required and ensure that the only patients who visit the clinic for treatment are truly those who need it.

Dr de Smet is director of MIOS, Lausanne, Switzerland (www.retina-uveitis.eu) and medical director of Preceyes Medical Robotics (www.preceyes.nl), Eindhoven, The Netherlands.He has no financial disclosures related to the content of this article.

Dr Mura is chief of the Retina Division, King Khaled Eye Specialist Hospital in Riyadh, Saudi Arabia and an associate Prof of ophthalmology at the Wilmer Eye Institute, Johns Hopkins University School of Medicine in Baltimore, USA. Dr Mura has no financial interests in the subject matter.

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Articles

To maintain treatment quality and patient and staff safety in the SARS-CoV-2 era, it is important to minimise clinic visits and maximise use of imaging modalities. In addition, extending treatment intervals with longer-acting agents is key to maximising safety and patients’ vision outcomes.

Author | Dr Marc D. de Smet

Articles

Maintaining quality and safety in retina clinics during a pandemic