FRINK Linked Data Fragments server

Matches in SemOpenAlex for { <https://semopenalex.org/work/W4245215485> ?p ?o ?g. }

• W4245215485 abstract "Accurate, reliable quantification of brain volume change (BVC) in AD patients is important. This can be affected, however, by local-volume changes related to MRI-scanner-gradient nonlinearities and inconsistent positioning of subjects within the scanner (particularly along the Z-axis). Furthermore, standard canthomeatal (CM) alignment results in the cerebrum centered several cms away from isocenter (Fig-A). Use simulated MRI data to model the effect of Z-shift-associated gradient-distortion (GD) on SIENA-generated measures of %-BVC (PBVC). High-resolution, volumetric T1-weighted MRI data were acquired in 9 normal adults on a Siemens Sonata 1.5T scanner after: (i) CM-alignment (CM, Fig-A), (ii) moving the scanner bed 50-mm out of the magnet (Z50), and (iii) accurate-as-possible CM repositioning (Repos). A GD field was generated using spherical harmonic expansion to map coordinates from an “ideal” coordinate system (a Lego-DUPLO® phantom) to the imaging coordinate system of the scanner (Fig-B). For each CM image, Z-shifts were simulated in 5-mm steps from -50-mm to +50-mm by applying the inverse of the GD, Z-shifting the image, reapplying the GD, and shifting the resulting images back. SIENA v2.5 was used to quantify the effect of a range of simulated between-scan Z-shifts similar to those seen in multicenter clinical-trial data in terms of: (i) magnitude, and (ii) location around which they were centered. Evidence for the validity of this approach is shown in Fig-C. As shown in Fig-D, (i) simulated 10-mm Z-shifts resulted in absolute errors (AE) greater than Repos-vs-CM (dashed horizontal lines) when they were centered furthest into the magnet (i.e., with the cerebrum centered even farther away from isocenter); (ii) simulated Z-shifts of 20-, 30-, and 40-mm resulted in similar findings, but with AEs become progressively greater and being seen with Z-shifts centered progressively less far into the magnet; and (iii) simulated 50-mm Z-shifts consistently resulted in substantial AEs in almost all subjects throughout the range of simulations. Z-shift-associated GDs can have significant effects on observed SIENA-PBVC values, with Z-shifts of similar magnitude having different effects depending on where they are centered. Consistent alignment of the centers of the cerebrum and magnet should decrease the effects of GD on observed BVC and increase statistical power." @default.
• W4245215485 created "2022-05-12" @default.
• W4245215485 creator A5014525522 @default.
• W4245215485 creator A5038879725 @default.
• W4245215485 creator A5048556145 @default.
• W4245215485 creator A5065754098 @default.
• W4245215485 creator A5068411980 @default.
• W4245215485 creator A5079184738 @default.
• W4245215485 date "2009-07-01" @default.
• W4245215485 modified "2023-09-23" @default.
• W4245215485 title "P2-020: The effect of head positioning and repositioning on SIENA-generated measures of brain volume change: Results from Simulated Z-shifts" @default.
• W4245215485 doi "https://doi.org/10.1016/j.jalz.2009.04.329" @default.
• W4245215485 hasPublicationYear "2009" @default.
• W4245215485 type Work @default.
• W4245215485 citedByCount "0" @default.
• W4245215485 crossrefType "journal-article" @default.
• W4245215485 hasAuthorship W4245215485A5014525522 @default.
• W4245215485 hasAuthorship W4245215485A5038879725 @default.
• W4245215485 hasAuthorship W4245215485A5048556145 @default.
• W4245215485 hasAuthorship W4245215485A5065754098 @default.
• W4245215485 hasAuthorship W4245215485A5068411980 @default.
• W4245215485 hasAuthorship W4245215485A5079184738 @default.
• W4245215485 hasConcept C104293457 @default.
• W4245215485 hasConcept C120665830 @default.
• W4245215485 hasConcept C121332964 @default.
• W4245215485 hasConcept C126780896 @default.
• W4245215485 hasConcept C181401712 @default.
• W4245215485 hasConcept C194257627 @default.
• W4245215485 hasConcept C20556612 @default.
• W4245215485 hasConcept C2524010 @default.
• W4245215485 hasConcept C2779751349 @default.
• W4245215485 hasConcept C2989005 @default.
• W4245215485 hasConcept C33923547 @default.
• W4245215485 hasConcept C46141821 @default.
• W4245215485 hasConcept C46362747 @default.
• W4245215485 hasConcept C49040817 @default.
• W4245215485 hasConcept C62520636 @default.
• W4245215485 hasConcept C71924100 @default.
• W4245215485 hasConcept C80551277 @default.
• W4245215485 hasConceptScore W4245215485C104293457 @default.
• W4245215485 hasConceptScore W4245215485C120665830 @default.
• W4245215485 hasConceptScore W4245215485C121332964 @default.
• W4245215485 hasConceptScore W4245215485C126780896 @default.
• W4245215485 hasConceptScore W4245215485C181401712 @default.
• W4245215485 hasConceptScore W4245215485C194257627 @default.
• W4245215485 hasConceptScore W4245215485C20556612 @default.
• W4245215485 hasConceptScore W4245215485C2524010 @default.
• W4245215485 hasConceptScore W4245215485C2779751349 @default.
• W4245215485 hasConceptScore W4245215485C2989005 @default.
• W4245215485 hasConceptScore W4245215485C33923547 @default.
• W4245215485 hasConceptScore W4245215485C46141821 @default.
• W4245215485 hasConceptScore W4245215485C46362747 @default.
• W4245215485 hasConceptScore W4245215485C49040817 @default.
• W4245215485 hasConceptScore W4245215485C62520636 @default.
• W4245215485 hasConceptScore W4245215485C71924100 @default.
• W4245215485 hasConceptScore W4245215485C80551277 @default.
• W4245215485 hasIssue "4S_Part_9" @default.
• W4245215485 hasLocation W42452154851 @default.
• W4245215485 hasOpenAccess W4245215485 @default.
• W4245215485 hasPrimaryLocation W42452154851 @default.
• W4245215485 hasRelatedWork W1424749405 @default.
• W4245215485 hasRelatedWork W1580077993 @default.
• W4245215485 hasRelatedWork W2021076690 @default.
• W4245215485 hasRelatedWork W2048241981 @default.
• W4245215485 hasRelatedWork W2052018419 @default.
• W4245215485 hasRelatedWork W2069630527 @default.
• W4245215485 hasRelatedWork W2075760412 @default.
• W4245215485 hasRelatedWork W2549377837 @default.
• W4245215485 hasRelatedWork W3035470204 @default.
• W4245215485 hasRelatedWork W4308682682 @default.
• W4245215485 hasVolume "5" @default.
• W4245215485 isParatext "false" @default.
• W4245215485 isRetracted "false" @default.
• W4245215485 workType "article" @default.