Cost-effective and adaptable cataract surgery simulation with basic technology.

PURPOSE: To assess the subjective validity of a cost-effective and adaptable cataract surgery simulation technique using basic technology. METHODS: We devised and filmed a range of simulation techniques that mimic steps of phacoemulsification cataract surgery using various "everyday" basic materials. This video was combined in a "parallel" fashion with live cataract surgery so that all steps of surgery were simulated. Subsequently, we distributed an online subjective validation questionnaire on Google Forms with the embedded simulation video in a generic invitation that was forwarded via email and/or text messages/WhatsApp messenger amongst Ophthalmologists of all grades within our regions (Kent, Surrey and Sussex, London and Wales Postgraduate Deaneries). RESULTS: Face validity: 66 (99%) participants agreed that the explanations in the video were clear and 53 (79%) concurred with the realistic feel of simulated technique. Instrumentation and adaptations demonstrated were deemed user friendly and conducive to replicate by 99% participants. Content validity: 60 (90%) of participants agreed the techniques described in the video reflected the technical skills required to train cataract surgeons. Forty-nine (74%) agreed that the simulation techniques were relevant for acquiring other generic and transferable microsurgical and manual dexterity skills. CONCLUSIONS: We demonstrated subjective validity of our cost-effective cataract simulation technique. Our model can be used as an adjunct to intraocular and virtual reality training for cataract surgery by removing the barrier of cost and improved exposure to real instruments used in cataract surgery.

Low-tech intraocular ophthalmic microsurgery simulation: A low-cost model for home use.

In order to maintain manual dexterity and surgical skills, trainees are encouraged to partake in regular simulation. Current options for intraocular surgical simulation require specialist microscopic equipment which is expensive and requires access to simulation facilities. A set of core simulation exercises and basic surgical skills of performing the corneal incisions, capsulorhexis, improving the manual dexterity, and suturing were identified, discussed, and agreed among authors before designing this simulation exercise. In this paper, we propose a smartphone-based, low-cost, low-tech model with corresponding exercises for intraocular simulation that can be used at home for the above-mentioned surgical skill set. This model provides an easy, portable, and reproducible method of simulation and can serve as an adjunct to patient-facing surgical training, especially in the current pandemic, where the excess to the simulation facilities or setup of these facilities may be difficult.

Risk of Airborne COVID-19 Transmission While Performing Humphrey Visual Field Testing.

PRECIS: Designing and demonstrating an experiment that shows the risk of airborne transmission of COVID-19 between patients having visual fields analyzed is low. PURPOSE: The aim was to investigate the possibility of airborne transmission of COVID-19 during Humphrey visual field testing in a real-world scenario. METHODS: A particle counter was placed within the bowl of Humphrey visual field analyzer (HFA) before and after turning on the machine to ascertain the effect of the air current produced by the ventilation system on aerosols. A second experiment was run where the particle counter was placed in the bowl and recorded particulates, in the air, as a 24-2 SITA standard was performed by a mock patient and then again immediately after the patient had moved away. We measured aerosol particle counts sized ≤0.3 µm, >0.3≤0.5 µm, >0.5≤1 µm, >1≤2.5 µm, >2.5≤5 µm, and >5≤10 µm. RESULTS: Particulates of all sizes were shown to be significantly reduced within the bowl after turning the machine on, demonstrating that the air current produced by the HFA pushes air out of the bowl and it cannot stagnate. There was no significant difference in measurement of aerosol while there was a patient performing the test and immediately after they had moved away, suggesting that aerosols breathed out by the patient are not able to remain in suspension in the bowl because of the ventilation current. CONCLUSION: There is no significant difference between aerosol count in the bowl of a HFA before, during and after testing. This suggests the risk of airborne transmission of COVID-19 is low between subsequent patients. This is in keeping with manufacturer's guidance on Humphrey visual field testing.

Aerosol generation during phacoemulsification in live patient cataract surgery environment.

PURPOSE: To investigate whether phacoemulsification is an aerosol-generating procedure in a live patient environment. SETTING: New Hayesbank Ophthalmology Services, Kent, United Kingdom. DESIGN: In vivo experimental human eyes study. METHODS: Aerosol particle counts sized 0.3 µm or lesser, more than 0.3 to 0.5 µm or lesser, more than 0.5 to 1 µm or lesser, more than 1 to 2.5 µm or lesser, more than 2.5 to 5 µm or lesser, and more than 5 to 10 µm or lesser were measured during elective phacoemulsification surgery of 25 eyes. The baseline particle count in the operating theater was measured on 2 separate days to assess for fluctuation. Then, 5 readings each during prephacoemulsification and phacoemulsification of all eyes were measured. The difference in aerosol generation during prephacoemulsification and phacoemulsification was also measured with the use of the mobile laminar air flow (LAF) machine. Finally, aerosol generation during phacoemulsification was measured using 2% hydroxypropyl methylcellulose (HPMC). RESULTS: There was no statistically significant difference in measurement of aerosol between the baseline measurements on both days and between each patient's prephacoemulsification and phacoemulsification stages of surgery. The LAF system showed statistically significant reduction in particles size of 0.3 µm or lesser, more than 0.3 to 0.5 µm or lesser, more than 0.5 to 1 µm or lesser, more than 1 to 2.5 µm or lesser, more than 2.5 to 5 µm or lesser, and more than 5 to 10 µm during phacoemulsification compared with that during prephacoemulsification (P value .00 for all particle sizes, t test). The use of 2% HPMC did not show any statistically significant reduction in particle measurements. CONCLUSIONS: Aerosol particles sized less than 10 µm are not produced during phacoemulsification of human crystalline lens in a live patient setting. The use of a mobile LAF machine significantly reduced the number of particles sized 10 µm or lesser within the surgical field.