9 research outputs found
Transcatter X-Ray Technique for the Inspection of Insulated, Oil-Carrying Pipelines
Pipelines are subjected to corrosion and require periodic inspection. These pipes are generally covered with an insulating material, that is contained within a metal jacket. The removal of the insulating material is costly, and can hazardous if asbestos is the material being removed. Because a large number of pipes need to be inspected, a cost effective technique for the characterization of corrosion under insulation is desirable
Local progression kinetics of geographic atrophy in age-related macular degeneration are associated with atrophy border morphology
Purpose: To assess the impact of distinct atrophy border characteristics based on spectral-domain optical coherence tomography (SD-OCT) imaging on local atrophy progression.
Methods: Patients with geographic atrophy (GA) secondary to AMD were recruited in the context of the Longitudinal Fundus Autofluorescence in Age-related Macular Degeneration and Directional Spread in Geographic Atrophy studies (NCT00393692, NCT02051998). Horizontal and vertical SD-OCT scans were acquired at sequential visits using a device allowing for anatomically accurate registration of follow-up to baseline scans. For quantification of local atrophy progression, the lateral spread of GA (LSGA) was measured. Further, border types were independently graded. Comparison of LSGA between the different border types was performed using linear mixed-effects models.
Results: Seventy-two eyes of 49 patients (27 female) aged 74.0 years (Inter quartile range [IQR], 68.1–79.0) were included into this analysis. A total of 258 border sections were analyzed longitudinally over a median period of 1.2 years (IQR, 0.9–1.6). At baseline, 17.1% borders were classified as ‘regular', 47.7% as ‘irregular', and 35.3% as ‘splitting'. Sixty-two percent of the eyes exhibited more than one border type. LSGA was slowest in ‘regular' borders (62.85 ± 25.29 μm/y), followed by ‘irregular' borders (91.15 ± 15.05 μm/y) and fastest in ‘splitting' borders (183.15 ± 18.17 μm/y). Differences between the ‘splitting' and each other border type were statistically significant (P
Conclusions: The results indicate that SD-OCT–based assessment of local GA border morphology can serve as a predictor for local atrophy progression. These observations help to better understand the natural history and potential pathogenetic factors of GA development and progression.</p