Purpose To assess inter-observer agreement between two corneal specialists grading Fuchs dystrophy clinically, and to determine if the corneal central to peripheral thickness ratio (CPTR) might be an alternative and objective metric of disease severity. Design Cross-sectional study. Participants Forty-five eyes (26 subjects) with mild and moderate Fuchs dystrophy, 73 eyes (60 subjects) with advanced Fuchs dystrophy, and 267 eyes (142 subjects) with normal corneas. Methods Corneas with Fuchs dystrophy were graded by two corneal specialists based on the confluence and area of guttae, and the presence or absence of edema. Central corneal thickness (CCT) and peripheral corneal thickness at 4 mm from the center (PCT4) were measured by using scanning-slit pachymetry. CPTR4 was the quotient of CCT and PCT4. Main Outcome Measures Inter-observer agreement for clinical grade; CPTR4. Results Inter-observer agreement for clinical grading of Fuchs dystrophy was moderate (κ=0.32, 95% confidence interval, 0.19-0.45). In normal corneas, CCT was not correlated with age (r= -0.10, p=0.28, n=267), PCT4 decreased with age (r= -0.33, p<0.001, n=254), and CPTR4 increased with age (r= 0.59, p<0.001, n=254). CCT was higher in Fuchs dystrophy (652 ± 61 μm, n=118) than in normal corneas (559 ± 31 μm, n=267, p<0.001). PCT4 was higher in Fuchs dystrophy (650 ± 51 μm, n=107) than in normal corneas (643 ± 43 μm, n=254, p<0.001 after adjusting thickness for age). CPTR4 was higher in advanced Fuchs dystrophy (1.03 ± 0.07, n=65) than in mild and moderate Fuchs dystrophy (0.95 ± 0.07, n=42, age-adjusted p<0.001), which in turn was higher than in normal corneas (0.87 ± 0.05, n=254, age-adjusted p<0.001). CPTR4 was highly correlated with clinical grade of Fuchs dystrophy (r=0.77, p<0.001, n=361). CPTR4 was repeatable (median coefficient of variation, 1.3%), and provided excellent discrimination between Fuchs dystrophy and normal (area under the receiver operator characteristic curve, 0.93). Conclusions Agreement between corneal specialists for the subjective and morphologic clinical grading of Fuchs dystrophy is only moderate. The corneal CPTR is an objective, repeatable, and possibly functional, metric of severity of Fuchs dystrophy that warrants further investigation to determine its role in monitoring disease progression and predicting the need for keratoplasty.

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We successfully observed 191 near-Earth asteroids using the Arecibo Observatory’s S-band planetary radar system from 2017 December through 2019 December. We present radar cross sections for 167 asteroids; circular-polarization ratios for 112 asteroids based on Doppler-echo-power spectra measurements; and radar albedos, constraints on size and spin periods, and surface-feature and shape evaluation for 37 selected asteroids using delay-Doppler radar images with a range resolution of 75 m or finer. Out of 33 asteroids with an estimated effective diameter of at least 200 m and sufficient image quality to give clues of the shape, at least 4 (∼12%) are binary asteroids, including 1 equal-mass binary asteroid, 2017 YE5, and at least 10 (∼30%) are contact-binary asteroids. For 5 out of 112 asteroids with reliable measurements in both circular polarizations, we measured circular-polarization ratios greater than 1.0, which could indicate that they are E-type asteroids, while the mean and the 1σ standard deviation were 0.37 ± 0.23. Further, we find a mean opposite-sense circular-polarization radar albedo of 0.21 ± 0.11 for 41 asteroids (0.19 ± 0.06 for 11 S-complex asteroids). We identified two asteroids, 2011 WN15 and (505657) 2014 SR339, as possible metal-rich objects based on their unusually high radar albedos, and discuss possible evidence of water ice in 2017 YE5.

IMPORTANCE External surgical treatment of involutional ptosis with normal levator function is challenging owing to lack of an established algorithm. Developing an algorithm-based technique could improve postoperative results while limiting intraoperative inefficiencies. OBJECTIVE To investigate the postoperative success of an algorithmic external levator aponeurosis resection technique for aponeurotic ptosis with good levator function. DESIGN, SETTING, AND PARTICIPANTS This retrospective cohort study included patients with involutional ptosis and normal levator function who were treated from July 1, 2015, through November 30, 2016, at a private ophthalmic plastic surgery clinic. INTERVENTIONSThe technique involved a small incision in the eyelid crease, with dissection through the orbital septum to expose the levator aponeurosis. The leading edge of the aponeurosis was then clamped to a medical-grade spring scale to standardize the stress on the eyelid between patients. Two millimeters of aponeurosis were resected for every 1 mm of desired ptosis correction. Two sutures were then placed to connect the aponeurosis to the tarsus at predetermined locations. MAIN OUTCOMES AND MEASURES Preoperative predicted (goal) vs actual margin reflex distance-1 (MRD1).RESULTS Twenty-six eyelids of 15 patients (6 men and 9 women; mean [SD] age, 65 years [range, 17-84 years]) met inclusion criteria. The mean follow-up was 189 days (range, 63-343 days). The mean preoperative MRD1 was 0.44 mm (range, −0.5 to 2 mm; 95% CI, 0.18-0.70 mm) compared with the final mean MRD1 of 3.2 mm (range, 2.5-4.0 mm; 95% CI, 3.1-3.4 mm; P < .001). The mean predicted goal MRD1 was 3.4 mm (range, 2.5-4.0 mm; 95% CI, 3.2-3.5 mm). The final MRD1 of all eyelids was within 1 mm of the goal MRD1. The mean surgical time per eyelid was 14.6 minutes (range, 10.5-34.0 minutes). Twelve eyelids (46%) did not have intraoperative suture adjustments. CONCLUSIONS AND RELEVANCEIn correcting aponeurotic ptosis, a small-incision levator aponeurectomy incorporating an algorithm and consistent stress on the aponeurosis during resection achieves the goal MRD1 efficiently. The algorithm closely estimates the desired height intraoperatively such that only small intraoperative suture height revisions, if any, are needed. No intraoperative adjustments were made in 12 eyelids, necessitating future studies to determine whether any adjustments are needed.LEVEL OF EVIDENCE 3.

The levator aponeurosis obtained during surgical correction of acquired ptosis elongates in response to nominal external forces. This biomechanical property is important because the length of the aponeurosis may vary intraoperatively if variable forces are applied to the eyelid. This property might be related to connective tissue architecture and, specifically, fibrosis. Surgeons performing levator aponeurosis resection should be mindful to maintain a consistent amount of force on the levator aponeurosis when performing the resection to maximize intercase consistency.