Assessing the Safety of Outpatient Cataract Surgery
How safe is outpatient cataract surgery, especially if anesthesiology staff are not immediately at hand? Koolwijk et al. evaluated their non–anesthesia-supported cataract service and found that the surgery can indeed be safely performed in such a setting.
For this retrospective observational study, the researchers evaluated patients who were slated to undergo elective phacoemulsification under topical anesthesia in their outpatient unit over a two-year period. This particular unit is situated within—but operates largely independent of—its parent hospital, which is a tertiary care facility in the Netherlands. The hospital’s medical emergency team (MET) was available as needed.
All told, 6,961 cases (4,347 patients) were eligible for analysis. The primary outcome measure was the incidence of adverse events requiring MET interventions. Secondary outcomes included surgical ocular complication rates and the rate of patient transfers to the hospital’s classic operating room.
Three patients needed attention from the hospital’s MET unit, for an intervention rate of 0.04 percent, and were diagnosed as having vasovagal collapse. Two occurred during the postop period, and the third occurred during the first checkup. All three patients recuperated uneventfully, without needing to be hospitalized. Surgical complications such as posterior capsule rupture and iris trauma occurred in 71 patients.
A total of 38 patients underwent surgery in the hospital’s operating room, and all but one from this group received general anesthesia. Reasons for the transfer to this setting included cognitive impairment and/or psychological factors such as claustrophobia and significant anxiety, as well as the patient’s expressed wish.
Preferred Testing Methods for Hydroxychloroquine Toxicity
Because detecting hydroxychloroquine retinal toxicity presents several practical challenges for ophthalmologists, Cukras et al. set out to compare subjective and objective testing methods.
The investigators found that spectral-domain optical coherence tomography (SD-OCT) and automated visual field testing are objective measures that demonstrate clinically useful sensitivity and specificity. In addition, they report that these two tests may be used as reasonable surrogates for the gold standard, multifocal electroretinography (mfERG), which is not widely available at this time.
For this prospective, single-center case-control study, the researchers assessed 57 patients who had been treated with hydroxychloroquine for at least five years. The patients were evaluated with color fundus photography, fundus autofluorescence imaging, SD-OCT, Humphrey 10-2 visual field testing, and mfERG. The mfERG parameters were used to classify the presence (n = 19) or absence (n = 38) of hydroxychloroquine retinal toxicity.
Using a polynomial modeling approach, the researchers found that visual field mean deviation and OCT retinal thickness measurements were the variables most strongly associated with the presence of hydroxychloroquine toxicity as identified by mfERG testing.
Based on these findings, they concluded that these two tests can be used in combination as a screening tool to identify patients with possible hydroxychloroquine toxicity. The ophthalmologist can then consider results of additional testing and the consistency of the evidence in deciding whether or not to recommend discontinuation of the drug.
Link Between Diabetes and Glaucoma
Zhao et al. investigated the suggested link between diabetes and the risk of primary open-angle glaucoma (POAG). They found that the presence and duration of diabetes were associated with an increased risk of glaucoma, ocular hypertension (OHT), and increased intraocular pressure (IOP). They also found a weak association between fasting glucose levels and higher IOP.
For this systematic review and meta-analysis, the authors identified 47 studies that involved nearly 3 million individuals from 16 countries. Of the studies, 16 were conducted in North America, 15 in Asia, 11 in Europe, two in Australia, and one each in Africa, the Middle East, and the West Indies. The majority of the studies (n = 32) were cross sectional, although six were longitudinal. Five had dose-response data on diabetes duration.
Across all studies, the prevalence of glaucoma ranged from 1.5 to 8.1 percent, and the prevalence of OHT ranged from 1.1 to 10.9 percent. The pooled relative risk for glaucoma was 1.48 in patients with diabetes versus those without diabetes. Moreover, the risk of glaucoma increased by 5 percent for each year after the initial diagnosis of diabetes. The pooled average difference in IOP between patients with and without diabetes was 0.18 mmHg, whereas the pooled average increase in IOP associated with an increase of 10 mg/dL in fasting glucose was 0.09 mmHg.
Ophthalmology summaries are written by Jean Shaw and edited by Susan M. MacDonald, MD.
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American Journal of Ophthalmology
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