Reliability of HR-pQCT Derived Cortical Bone Structural Parameters When Using Uncorrected Instead of Corrected Automatically Generated Endocortical Contours in a Cross-Sectional Study: The Maastricht Study.
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ABSTRACT:
SUBMITTER: de Waard EAC
PROVIDER: S-EPMC6105151 | biostudies-literature | 2018 Sep
REPOSITORIES: biostudies-literature
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Reliability of HR-pQCT Derived Cortical Bone Structural Parameters When Using Uncorrected Instead of Corrected Automatically Generated Endocortical Contours in a Cross-Sectional Study: The Maastricht Study.
de Waard Ellis A C EAC Sarodnik Cindy C Pennings Alexander A de Jong Joost J A JJA Savelberg Hans H C M HHCM van Geel Tineke A TA van der Kallen Carla J CJ Stehouwer Coen D A CDA Schram Miranda T MT Schaper Nicolaas N Dagnelie Pieter C PC Geusens Piet P M M PPMM Koster Annemarie A van Rietbergen Bert B van den Bergh Joop P W JPW
Calcified tissue international 20180329 3
Most HR-pQCT studies examining cortical bone use an automatically generated endocortical contour (AUTO), which is manually corrected if it visually deviates from the apparent endocortical margin (semi-automatic method, S-AUTO). This technique may be prone to operator-related variability and is time consuming. We examined whether the AUTO instead of the S-AUTO method can be used for cortical bone analysis. Fifty scans of the distal radius and tibia from participants of The Maastricht Study were e ...[more]
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Project description:ImportanceAccurate determination of intraocular pressure (IOP) is crucial for the diagnosis and management of glaucoma. Objective clinical evaluation of the correction equations for Goldmann applanation tonometry (GAT) is lacking.ObjectivesTo investigate the difference between corrected and conventional GAT and Pascal dynamic contour tonometry (DCT) measurements, as well as the correlation between discordant IOP values and stage of glaucoma.Design, setting, and participantsThis prospective cross-sectional case series was conducted at the Department of Ophthalmology, University Hospital Zurich, and Talacker Eye Center between July 1, 2011, and May 31, 2016, among 112 white patients with glaucoma.InterventionsIntraocular pressure measurements were performed with GAT and DCT in a randomized order. Goldmann applanation tonometry measurements were modified with 5 correction equations.Main outcomes and measuresThe primary end point was degree of concordance between corrected or uncorrected GAT and DCT measurements. The secondary end point was association between discordant IOP measurements and the stage of glaucoma, as assessed by the Glaucoma Severity Score.ResultsAmong the 112 patients (67 women and 45 men; mean [SD] age, 66.3 [13.1] years), 63 of the eyes in the study (56.3%) were left eyes and 85 patients (75.9%) were taking ocular antihypertensive medications. Mean (SD) IOP was 20.3 (4.5) mm Hg (95% CI, 19.4-21.1) as measured by DCT and 17.0 [4.1] mm Hg (95% CI, 16.3-17.8) as measured by GAT. The mean (SD) discordance between DCT and GAT measurements was -3.3 (2.0) mm Hg (95% CI, 2.9-3.6). The 5 corrected GAT values ranged from -2.7 to -5.4 mm Hg compared with DCT. The mean (SD) result of the Dresdner correction formula (17.6 [4.1] mm Hg) was closer to the DCT measurement than the original GAT measurement. The mean (SD) Glaucoma Severity Score was 4.7 (3.4) (95% CI, 4.1-5.4). The uncorrected discordance IOPDCT - IOPGAT showed a positive correlation with the Glaucoma Severity Score (rs = 0.33; P < .001) and a negative correlation with central corneal thickness (rs = -0.22; P = .02).Conclusions and relevanceIn comparison with DCT measurements, these data suggest that GAT values are significantly discordant in eyes with thin corneas and advanced glaucoma. Application of GAT-based correction formulas involves a possible risk of creating an even greater number of unpredictable measurement errors. Hence, we advise with caution, especially pertaining to eyes with thin corneas, to not place reliance on GAT readings, and abandon any correction formula.Trial registrationclinicaltrials.gov Identifier: NCT01474070.
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