This Issue at a Glance

Abstract

Zetterberg et al (p. 305) conducted a retrospective, registry-based study to determine the change in the proportion of high-volume cataract surgeons between 2007 and 2016 and investigate the effect of operation volume per surgeon and clinical unit on the rate of posterior capsule rupture (PCR). The researchers analyzed data from the Swedish National Cataract Register between 2007 and 2016 and found that the proportion of cataract procedures performed by high- (≥500 procedures yearly) or very high- (≥1000 procedures yearly) volume cataract surgeons increased from 36.9% in 2007 to 68.1% in 2016 and from 8.7% to 33.7%, respectively. The yearly incidence of PCR decreased with more procedures, from 2.15% for low-volume surgeons (10–99 procedures/ year) to 0.59% for high-volume surgeons. Preoperative best-corrected visual acuity was significantly better in eyes operated on by high-volume and very high-volume cataract surgeons. There was no significant difference in the rate of capsule complications seen between clinical units with high or low operation volume. The researchers conclude that there is a strong association of the rate of capsule complications with operation volume of individual surgeons but not that of individual clinical units. Christopher et al (p. 346) set out to develop and evaluate a deep learning system to identify eyes with glaucomatous visual field damage (GVFD) and predict the severity of GVFD using spectral domain OCT (SD OCT) optic nerve head images. A total of 9765 visual field (VF) SD OCT pairs were collected from 1909 eyes from 1194 participants with and without GVFD. Deep learning models outperformed standard retinal nerve fiber layer (RNFL) thickness measurements in identifying GVFD and predicting all quantitative VF metrics to estimate the severity of functional loss, with the deep learning model based on RNFL en face images performing particularly well. The researchers conclude that deep learning models based on SD OCT images had high accuracy in identifying eyes with GFVD and predicting the severity of functional loss, and they suggest that these models could help clinicians estimate visual function from SD OCT imaging and more effectively individualize the frequency of VF testing to the individual patient. In a retrospective cohort study, Parikh et al (p. 296) characterized surgical confusions in ophthalmology to identify their incidence, root causes, and impact on patients and physicians. The study included 143 cases that occurred between January 1, 2006, and December 31, 2017, of which 92 cases (64.3%) were preventable using the Universal Protocol. There were 95 cases (66.4%) of incorrect implants during cataract surgery, of which 33 cases (34.7%) were not preventable by the Universal Protocol because of upstream errors originating before the actual day of surgery. The most common root cause of confusion was an inadequately performed time out, which was responsible for 46 cases (32.2%). Incorrect lens orders or calculations before surgery (upstream errors) were the second most common cause of surgical confusion, involving 31 cases (21.7%). The average legal indemnity ranged from $0 up to $284 000 and was $57 514 for incorrect implant during cataract surgery. The researchers conclude that surgical confusions are relatively rare in ophthalmology, and most could have been prevented by following the Universal Protocol. Kong et al (p. 324) conducted a retrospective, observational cohort study using a large United States administrative data set to analyze the incidence rate (IR) of herpes zoster ophthalmicus (HZO) and differences by age, gender, race, and region from 1994 through 2018. From January 1, 1994, through December 31, 2018, 633 474 cases of herpes zoster (HZ) were reported, with 49 745 (7.9%) having HZO. The incidence of HZO increased from 1994 through 2018 by an estimated 1.1 cases per 100 000 person-years annually, with an estimated relative increase of 3.6% annually. In all ages over 10 years HZO IR increased until 2007, then began declining significantly in individuals younger than 21 and older than 60, stabilizing in individuals 21 to 30 years old, and increasing more slowly among individuals 31 to 60 years old. Female patients and white patients were at higher risk of developing HZO. The researchers conclude that HZO IR has increased 3.6% per year from 1994 to 2018 in the United States, and since 2008 HZO rates have declined in the youngest and oldest age groups while continuing to increase among individuals between 31 to 60 years of age, representing a shift in HZO burden towards middle age individuals. Since vaccination currently targets the pediatric and older populations, these findings prompt reconsideration of vaccination recommendations for middle-aged adults.