Alterations in the ocular surface and tear film following keratoplasty.

The purpose of this study was to evaluate any alterations in the tear film and ocular surface beyond the early postoperative period following penetrating keratoplasty (PK) and deep anterior lamellar keratoplasty (DALK). This cross-sectional, contralateral-eye study compared ocular surface and tear film parameters of eyes with a previous PK or DALK in one eye and no prior surgery in the contralateral eye. Overall, 14 (87.5%) participants underwent PK, and 2 (12.5%) underwent DALK using a mechanical dissection. The median time from surgery was 3.4 years (range 1.5 to 38.7 years). The indication for unilateral keratoplasty was keratoconus in 15 (94%) participants, and corneal scarring in 1 (6%) eye, secondary to microbial keratitis. Operated eyes exhibited poorer non-invasive tear film breakup time, lower corneal sensitivity, lower sub-basal nerve density and more severe fluorescein staining scores than unoperated fellow eyes (all Q < 0.05). There were no significant differences in tear film lipid layer quality, tear meniscus height, conjunctival hyperaemia, lissamine green staining score, or meibography grade between operated and fellow eyes (all Q ≥ 0.20). Higher corneal esthesiometry threshold (lower corneal sensitivity) was correlated with shorter non-invasive tear film breakup time (Spearman's rho = - 0.361, p = 0.04) and increased fluorescein staining score (Spearman's rho = 0.417, p = 0.02). Keratoplasty can induce persistent changes in the ocular surface and tear film, including: increased fluorescein staining, decreased tear film breakup time, decreased corneal sub-basal nerve plexus density, and reduced corneal sensitivity.

Always-On Sub-Microwatt Spiking Neural Network Based on Spike-Driven Clock- and Power-Gating for an Ultra-Low-Power Intelligent Device.

This paper presents a novel spiking neural network (SNN) classifier architecture for enabling always-on artificial intelligent (AI) functions, such as keyword spotting (KWS) and visual wake-up, in ultra-low-power internet-of-things (IoT) devices. Such always-on hardware tends to dominate the power efficiency of an IoT device and therefore it is paramount to minimize its power dissipation. A key observation is that the input signal to always-on hardware is typically sparse in time. This is a great opportunity that a SNN classifier can leverage because the switching activity and the power consumption of SNN hardware can scale with spike rate. To leverage this scalability, the proposed SNN classifier architecture employs event-driven architecture, especially fine-grained clock generation and gating and fine-grained power gating, to obtain very low static power dissipation. The prototype is fabricated in 65 nm CMOS and occupies an area of 1.99 mm2. At 0.52 V supply voltage, it consumes 75 nW at no input activity and less than 300 nW at 100% input activity. It still maintains competitive inference accuracy for KWS and other always-on classification workloads. The prototype achieved a power consumption reduction of over three orders of magnitude compared to the state-of-the-art for SNN hardware and of about 2.3X compared to the state-of-the-art KWS hardware.

New Zealand adult ocular trauma study: A 10-year national review of 332 418 cases of ocular injury in adults aged 18 to 99 years.

IMPORTANCE: Ocular injury is a common, preventable cause of temporary and permanent disability. BACKGROUND: The current study evaluates the nationwide incidence, demographics and visual outcomes of adults with ocular injury in New Zealand. DESIGN: Nationwide retrospective review. PARTICIPANTS: New Zealanders aged 18-99 years from 2007 to 2016 with ocular injury requiring assessment by a registered medical practitioner. METHODS: New Zealand national and regional datasets were used to evaluate population-level statistics over a 10-year period. Visual and clinical outcome data were assessed using a random sample of 150 patients from a tertiary hospital. MAIN OUTCOME MEASURES: Annual incidence, aetiology, demographics, injury location, visual outcomes, protective eyewear use, surgical intervention and follow-up. RESULTS: A total of 332 418 adult eye injuries were recorded nationally. The annual incidence of eye injury was 1007/100 000 population/year. Patients were predominantly male (76.1%), of New Zealand-European ethnicity (74.6%) and aged between 20 and 29 years (21.1%). The most common mechanism of injury was "struck by object" (55.4%). Injuries occurred most commonly at home (48.4%), followed by commercial (15%) and industrial locations (13.8%). Injuries were more common in rural regions (P < .001). Protective eyewear use was reported in 6% of cases (n = 9, 95% confidence interval = 3.2-11.0). Most ocular injuries were managed exclusively in primary care (70.5%). CONCLUSIONS AND RELEVANCE: Adults with the highest risk of ocular injury are rural males aged 20 to 29 years. Protective eyewear use is uncommon in adults presenting with ocular injury and the majority of injuries are managed in primary care. Promotion of appropriate injury prevention strategies is an important public health message.

Risk-Adjusted CUSUM Analysis of the Learning Curve of Femtosecond Laser Assisted Cataract Surgery.

Objectives: To determine the length of the learning curve of femtosecond laser-assisted cataract surgery (FLACS) by a risk-adjusted cumulative sum method. Materials and Methods: This was a retrospective review of the first 288 FLACS performed by three surgeons over a 12-month period. The learning curves were analyzed separately for each surgeon and as pooled data via risk-adjusted cumulative sum methods. Change-point analysis was performed to estimate the length of the learning curve. Results: Rates of complications were as follows: anterior capsular tear (ACT) (3.4%), posterior capsular rupture (PCR) (0.7%), vitreous loss (0.3%), iris trauma (0.7%), Descemet's membrane tear (0.3%). There was a strong confidence level (96%) that there was a stable performance in terms of PCR after case 16 for the pooled data. Surgeon 1 did not have any cases of PCR, surgeons 2 and 3 exhibited change points at case 5 and 16, respectively (confidence levels = 99%, 98%). There was a strong confidence level (99.8%) that there was stable performance in terms of ACT after case 14 for the pooled data, however the individual surgeons demonstrated individual change points at case 1 (surgeon 1, confidence 99%), case 14 (surgeon 2, confidence 99%), and case 49 (surgeon 3, confidence 96%). Conclusions: The results suggest that there is an increased risk of ACT and PCR in FLACS within a surgeon's first 14 and 16 operations, respectively. Measures should be adopted to minimize harm to patients during this phase. However, overall rates of complications were safe.

New Zealand childhood ocular trauma study: Analysis of 75 601 cases of ocular injury from 2007 to 2016.

IMPORTANCE: Childhood ocular injury is a common, preventable cause of potentially severe permanent disability. BACKGROUND: This study evaluates the nationwide incidence, demographics and visual outcomes of children with ocular injury in New Zealand. DESIGN: Nationwide retrospective review. PARTICIPANTS: All children in New Zealand aged 0 to 17 years from 2007 to 2016 with ocular injury requiring assessment by a medical practitioner. METHODS: New Zealand national and regional datasets were used to evaluate population-level statistics for ocular injury over a 10-year period. Visual and clinical outcome data were assessed using a randomized sample of 150 patients. MAIN OUTCOME MEASURES: Annual incidence, aetiology, demographics, injury location, visual outcomes, protective eyewear use, surgical intervention and follow-up. RESULTS: A national total of 75 601 cases were included with a mean incidence of 719/100 000 children/year. Cases were predominantly male (63.2%) and of New Zealand-European ethnicity (60.8%), aged 0 to 4 years (30.66%). Injury cause was most commonly "struck by object" (53.7%) and occurred in the home (50.9%). Tertiary hospital assessment and treatment was required in 17.7% where final visual acuity of 6/12 or worse was noted in 19.7% and protective eyewear use was reported in 2.7%. Maori and Pacific ethnicities were associated with higher rates of permanent visual impairment. CONCLUSIONS AND RELEVANCE: Children with the highest risk of ocular injury are males aged 0 to 4 years. Children of Maori or Pacific Island ethnicity and aged 15 to 17 years have the highest risk of ocular injury resulting in permanent visual impairment. Protective eyewear use is uncommon in children presenting with ocular injury. Promotion of appropriate injury prevention strategies is an important public health message.

Randomized double-masked trial of eyelid cleansing treatments for blepharitis.

PURPOSE: To compare the efficacy of a dedicated eyelid cleanser and diluted baby shampoo in the management of blepharitis. METHODS: Forty-three participants with clinical blepharitis signs were enrolled in a prospective, randomized, double-masked, paired-eye trial. A dedicated eyelid cleanser (TheraTears® SteriLid®) was applied to the eyelids of one eye (randomized) and diluted baby shampoo (Johnson's® No More Tears®) to the fellow eye, twice daily for 4 weeks. Tear film parameters, ocular surface characteristics, symptomology and cytology markers were assessed at baseline and day 28. RESULTS: Baseline measurements did not differ between treatments (all p > 0.05). The eyelid cleanser was preferred over baby shampoo by the majority of participants (p < 0.001). Improvements in the tear lipid layer, inferior lid wiper epitheliopathy (LWE), cylindrical collarettes, and MMP-9 expression were limited to the dedicated eyelid cleanser (all p < 0.05), and a greater decrease in SANDE symptoms score was also observed (p = 0.04). Meibomian gland capping and MUC5AC expression worsened with baby shampoo treatment (both p < 0.05). SPEED symptoms score, superior LWE, seborrhoeic lash crusting, and trichiasis decreased significantly following application of both treatments (all p < 0.05), but did not differ between treatments (all p > 0.05). CONCLUSION: Clinical improvements in blepharitis occurred with both treatments. However, only the dedicated eyelid cleanser proved effective in reducing ocular surface inflammation, and was the preferred therapy. Long term impact of decreased goblet cell function secondary to baby shampoo treatment requires further exploration.