In:
Investigative Radiology, Ovid Technologies (Wolters Kluwer Health), Vol. 53, No. 7 ( 2018-7), p. 424-431
Abstract:
The aim of this study was to evaluate the reduction of artifacts from deep brain stimulation electrodes (DBS) using an iterative metal artifact reduction algorithm (O-MAR), virtual monoenergetic images (VMI), and both in combination in postoperative spectral detector computed tomography using a dual-layer detector (spectral detector computed tomography [SDCT]) of the head. Material and Methods Nonanthropomorphic phantoms with different DBS leads were examined on SDCT; in 1 phantom periprocedural bleeding was simulated. A total of 20 patients who underwent SDCT after DBS implantation between October 2016 and April 2017 were included in this institutional review board–approved retrospective study. Images were reconstructed using standard-of-care iterative reconstruction (CI) and VMI, each with and without O-MAR processing (IR and MAR). Artifacts were quantified by determining the percentage integrity uniformity in an annular region of 1.4 cm 2 around the DBS lead; a percentage integrity uniformity of 100% indicates the absence of artifacts. In phantoms, conspicuity of blood was determined on a binary scale, whereas in patients, image quality, DBS lead assessment, and extent of artifact reduction were assessed on Likert scales by 2 radiologists. Statistical significance was assessed using analysis of variance and Wilcoxon tests; sensitivity and specificity were calculated. Results The O-MAR processing significantly decreased artifacts in phantom and patients ( P ≤ 0.05), whereas VMI did not reduce artifact burden compared with corresponding CI ( P 〉 0.05): for example, CI-IR/MAR and 200 keV-IR/MAR for patients: 76.3%/90.7% and 75.9%/91.2%, respectively. Qualitatively, overall image quality was not improved ( P 〉 0.05) and MAR improved DBS assessment (CI-IR/MAR: 2 [1–3]/3 [2–4] ; P ≤ 0.05) and reduced artifacts significantly ( P ≤ 0.05). The O-MAR processing increased sensitivity for bleeding by 160%. In some cases, new artifacts were induced through O-MAR processing, none of which impaired diagnostic image assessment. Discussion The investigated O-MAR algorithm reduces artifacts from DBS electrodes and should be used in the assessment of postoperative patients; however, combination with VMI does not provide an additional benefit.
Type of Medium:
Online Resource
ISSN:
1536-0210
,
0020-9996
DOI:
10.1097/RLI.0000000000000460
Language:
English
Publisher:
Ovid Technologies (Wolters Kluwer Health)
Publication Date:
2018
detail.hit.zdb_id:
2041543-6
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