Microdroplet and spatter contamination during phacoemulsification cataract surgery in the era of COVID-19

Impacts of the COVID-19 pandemic on elective cataract surgeries

Objective

Methods

Results

Conclusion

Risk and Impact of Severe Acute Respiratory Syndrome Coronavirus 2 Infection on Corneal Transplantation: A Case-Control Study

PURPOSE

The purpose of this study was to evaluate the risk of symptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection after corneal transplantation surgery, with cataract surgeries as controls, and the impact of the novel coronavirus disease pandemic in the clinical and surgical complications of corneal transplantation and cataract surgeries.

METHODS

A retrospective matched case-control study of 480 consecutive individuals who underwent surgery at the Bascom Palmer Eye Institute between May 2020 and November 2020. A total of 240 patients who underwent corneal transplantation with tissue obtained from the Florida Lions Eye Bank were age, race, ethnicity, and sex matched with 240 patients who underwent cataract surgery during the same day and by the same surgical team. Only the first corneal transplant or cataract surgery during this period was considered for each individual. All donors and recipients were deemed SARS-CoV-2 negative by a nasopharyngeal polymerase chain reaction test before surgery. Postoperative SARS-CoV-2 infections were defined as previously SARS-CoV-2(-) individuals who developed symptoms or had a positive SARS-CoV-2 polymerase chain reaction test during the first postoperative month.

RESULTS

Mean age, sex, race, and ethnicity were similar between groups. There were no differences between the corneal transplant and cataract groups in the rates of SARS-CoV-2 infection before (5.8% vs. 7.5%, P= 0.6) or after surgery (2.9% vs. 2.9%, P = 1). The rates of postoperative complications did not increase during the pandemic, compared with previously reported ranges.

CONCLUSIONS

In this study, postoperative SARS-CoV-2 infection was similar for individuals undergoing corneal transplantation or cataract surgery. Further research is required to evaluate the transmission of SARS-CoV-2 through corneal tissue.

Changes to ophthalmic clinical care during the coronavirus disease 2019 pandemic

PURPOSE OF REVIEW

Given the impact that society as a whole, and medicine specifically, has experienced as a result of the COVID-19 pandemic, an examination of clinical care changes enacted in the field of ophthalmology is of interest to the specialty.

RECENT FINDINGS

In order to adapt to the reality of the COVID-19 pandemic, measures, such as broadening telehealth capabilities, adopting universal masking, careful sanitation procedures, applying virtual teaching in academic environments, and deferring elective surgeries were put in place. These were aimed at reducing person-to-person spread of SARS-CoV-2. Though best efforts were made at triaging ophthalmic emergencies during these times, unfortunate delays in care were observed in some circumstances. Finally, a prospective study interrogating the risk of spread at slit lamp distances for short periods of time was encouraging, suggesting low risk of transmissibility, though limited by a small case-positive sample size.

SUMMARY

Significant changes have been made in the design and delivery of ophthalmic care during the COVID-19 pandemic. Some of these, such as telemedicine, may provide value in a postpandemic world.

Phacoemulsification and nucleic acid-enriched aerosol: considerations from an eye model of cataract simulation

Purpose

The purpose of this study is to investigate whether phacoemulsification can generate aerosolized single-stranded RNA (ssRNA) and retain sequence integrity using an artificial eye model for experimental cataract surgery.

Methods

A simulation of cataract surgery was performed using an anterior chamber eye model filled with an ssRNA probe at different scalar dilutions (kanamycin positive control ssRNA). A plastic conical cage was built over the artificial eye surface of the mock-up. A total of 24 tests (twice reproduced) were performed, and five nitrocellulose strips were placed 15 cm from the artificial surface of the mock-up and used to collect aerosol particles, from each experiment. Phaco-activity was mimicked using a phacoemulsification equipped with a 2.75-mm tip, and strips were removed at the end of the procedure. RNA extraction, reverse transcription, and agarose gel electrophoresis were performed and compared.

Results

Strips collected aerosol droplets enriched with ssRNA, mainly at the higher concentrations tested, compared to related untouched standard solutions. Complementary DNA (cDNA) synthesis confirmed the presence of intact ssRNA fragments. As observed from densitometric analysis of resolved RNA in extracted samples and cDNA bands after retro-transcription, lower concentrations of ssRNA were also detected.

Conclusions

As the main output of the study, the phaco-generated aerosol can deliver an intact ssRNA sequence. Since the aerosol can potentially reach the operator’s face, any biological agent (virus/bacteria) potentially inside the anterior chamber of a patient undergoing cataract surgery, eventually escaping from biomolecular checks, can be potentially infective for operators. The data reported herein suggest that collective versus individual protective countermeasures should always be encouraged in ocular surgery and should not be restricted to coronavirus disease emergencies.

The Transmission of SARS-CoV-2 Infection on the Ocular Surface and Prevention Strategies

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global health problem. Although the respiratory system is the main impaired organ, conjunctivitis is one of its common findings. However, it is not yet understood if SARS-CoV-2 can infect the eye and if the ocular surface can be a potential route of SARS-CoV-2 transmissions. Our review focuses on the viral entry mechanisms to give a better understanding of the interaction between SARS-CoV-2 and the eye. We highlighted findings that give evidence for multiple potential receptors of SARS-CoV-2 on the ocular surface. Additionally, we focused on data concerning the detection of viral RNA and its spike protein in the various ocular tissues from patients. However, the expression level seemed to be relatively low compared to the respiratory tissues as a result of a unique environment surrounding the ocular surface and the innate immune response of SARS-CoV-2. Nevertheless, our review suggests the ocular surface as a potential route for SARS-CoV-2 transmission, and as a result of this study we strongly recommend the protection of the eyes for ophthalmologists and patients at risk.

Evidence of SARS-CoV-2 Transmission Through the Ocular Route

PURPOSE

Currently, the coronavirus disease 2019 (COVID-19) pandemic is raging around the world. However, the transmission of its pathogen, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is not fully clear. It is still controversial whether the ocular transmission of SARS-CoV-2 exists. This review aimed to summarize the evidence of SARS-CoV-2 ocular transmission.

METHODS

Online articles were searched till October 23, 2020 in Pubmed, Embase, and websites of World Health Organization, Centers for Disease Control and Prevention COVID-19, American Academy of Ophthalmology, and American Society of Cataract and Refractive Surgery under the search strategy of (((("COVID-19"[Mesh]) OR ("SARS-CoV-2"[Mesh])) OR (2019 novel coronavirus)) OR (2019-nCoV)) AND (((("Conjunctivitis"[Mesh]) OR (Ocular Surface)) OR ("Eye"[Mesh])) OR ("Ophthalmology"[Mesh])). The language was not restricted. After screening, 1445 records were excluded and 168 references original articles were finally included.

RESULTS

Cells of ocular surface express both the receptor of angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2), offering molecular bases for the ocular susceptibility to SARS-CoV-2. Accumulated COVID-19 patients presented conjunctivitis as the initial or the only symptom. Whether COVID-19 patients had ocular symptoms or not, SARS-CoV-2 was detectable on the ocular surface, and the isolated virus was infectious, proving that the ocular surface can not only be a reservoir but also a source of contagion. SARS-CoV-2 may reach the ocular surface by hand-eye contact and aerosols. Once SARS-CoV-2 reaches the ocular surface, it may transfer to other systems through the nasolacrimal system or hematogenous metastasis.

CONCLUSION

The ocular surface can serve as a reservoir and source of contagion for SARS-CoV-2. SARS-CoV-2 can be transmitted to the ocular surface through hand-eye contact and aerosols, and then transfer to other systems through nasolacrimal route and hematogenous metastasis. The possibility of ocular transmission of SARS-CoV-2 cannot be ignored.

Rethinking Elective Cataract Surgery Diagnostics, Assessments, and Tools after the COVID-19 Pandemic Experience and Beyond: Insights from the EUROCOVCAT Group

The progressive deterioration of the visual function in patients on waiting lists for cataract surgery has a negative impact on their quality of life, especially in the elderly population. Patient waiting times for cataract surgeries in many healthcare settings have increased recently due to the prolonged stop or slowdown of elective cataract surgery as a result of coronavirus disease 19 (COVID-19). The aim of this review is to highlight the impact of such a "de-prioritization" of cataract surgery and to summarize some critical issues and useful hints on how to reorganize cataract pathways, with a special focus on perioperative diagnostic tools during the recovery phase and beyond. The experiences of a group of surgeons originating from nine different countries, named the European COVID-19 Cataract Group (EUROCOVCAT), have been combined with the literature and recommendations from scientific ophthalmic societies and healthcare institutions. Key considerations for elective cataract surgery should include the reduction of the number of unnecessary visits and examinations, adoption of precautionary measures, and implementation of telemedicine instruments. New strategies should be adopted to provide an adequate level of assistance and to guarantee safety conditions. Flexibility will be the watchword and regular updates would be necessary following scientific insights and the development of the pandemic.