PurposeTo characterize the ocular surface microbiome of healthy volunteers using a combination of microbial culture and high-throughput DNA sequencing techniques.MethodsConjunctival swab samples from 107 healthy volunteers were analyzed by bacterial culture, 16S rDNA gene deep sequencing (n = 89), and biome representational in silico karyotyping (BRiSK; n = 80). Swab samples of the facial skin (n = 42), buccal mucosa (n = 50), and environmental controls (n = 27) were processed in parallel. 16S rDNA gene quantitative PCR was used to calculate the bacterial load in each site. Bacteria were characterized by site using principal coordinate analysis of metagenomics data. BRiSK data were analyzed for presence of fungi and viruses.ResultsCorynebacteria, Propionibacteria, and coagulase-negative Staphylococci were the predominant organisms identified by all three techniques. Quantitative 16S PCR demonstrated approximately 0.1 bacterial 16S rDNA/human actin copy on the ocular surface compared with greater than 10 16S rDNA/human actin copy for facial skin or the buccal mucosa. The conjunctival bacterial community structure is distinct compared with the facial skin (R = 0.474, analysis of similarities P = 0.0001), the buccal mucosa (R = 0.893, P = 0.0001), and environmental control samples (R = 0.536, P = 0.0001). 16S metagenomics revealed substantially more bacterial diversity on the ocular surface than other techniques, which appears to be artifactual. BRiSK revealed presence of torque teno virus (TTV) on the healthy ocular surface, which was confirmed by direct PCR to be present in 65% of all conjunctiva samples tested.ConclusionsRelative to adjacent skin or other mucosa, healthy ocular surface microbiome is paucibacterial. Its flora are distinct from adjacent skin. Torque teno virus is a frequent constituent of the ocular surface microbiome. (ClinicalTrials.gov number, NCT02298881.)

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The recent correspondence in the Journal on the use of in-circle vapourisers has been brought to my attention, and I feel that certain important facts must be stated.Many clinical anaesthetists can onfirrn the findings of Marriott that in-circle vapourisers with spontaneous ventilation provide completely safe anaesthetic conditions.

Purpose: Intravitreal injection therapy (IVIT) has transformed the management of many chorioretinal diseases. Although these treatments are effective, they can also be expensive. Using the Medicare Provider and Utilization Data Report (MPUDR), we aim to quantify the costs of these drugs to Medicare and to project future cost trends. Methods: Data were harvested from the MPUDR for all ophthalmology providers who delivered intravitreal injections (IVT) (CPT code 67028) during the years 2012-2016. Linear regression utilizing the MPUDR data was used to analyze cost trends and to project Medicare costs out to year 2026. Results: From 2012 to 2016, the total number of IVTs increased from 2 286 593 to 2 936 274 ( R2 = 0.98; P = .001). The per-beneficiary Medicare cost rose significantly from $3,148 to $3,945 ( R2 = 0.92; P = .03). The total cost to Medicare for IVIT increased from $1.68 billion to $2.73 billion ( R2 = 0.99; P < .005). IVIT accounts for 37% of all ophthalmology Medicare reimbursements. At the current rate, IVIT costs will exceed $5 billion per year by 2026. Conclusions: The total number of injections and costs for IVIT rose significantly from 2012 to 2016. At the current rate, Medicare reimbursement for brand-name drugs will make up a large proportion of future costs.