Efficient Inverse Isoparametric Mapping Algorithm for Whole-Body Computed Tomography Registration Using Deformations Predicted by Nonlinear Finite Element Modeling

Biomechanical modeling methods can be used to predict deformations for medical image registration and particularly, they are very effective for whole-body computed tomography (CT) image registration because differences between the source and target images caused by complex articulated motions and soft tissues deformations are very large. The biomechanics-based image registration method needs to deform the source images using the deformation field predicted by finite element models (FEMs). In practice, the global and local coordinate systems are used in finite element analysis. This involves the transformation of coordinates from the global coordinate system to the local coordinate system when calculating the global coordinates of image voxels for warping images. In this paper, we present an efficient numerical inverse isoparametric mapping algorithm to calculate the local coordinates of arbitrary points within the eight-noded hexahedral finite element. Verification of the algorithm for a nonparallelepiped hexahedral element confirms its accuracy, fast convergence, and efficiency. The algorithm's application in warping of the whole-body CT using the deformation field predicted by means of a biomechanical FEM confirms its reliability in the context of whole-body CT registration.

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Serum D-dimer level as a biomarker for identifying patients with isolated injury to prevent unnecessary whole-body computed tomography in blunt trauma care

Scandinavian Journal of Trauma Resuscitation and Emergency Medicine ◽

10.1186/s13049-020-00815-9 ◽

2021 ◽

Vol 29 (1) ◽

Author(s):

Rakuhei Nakama ◽

Ryo Yamamoto ◽

Yoshimitsu Izawa ◽

Keiichi Tanimura ◽

Takashi Mato

Keyword(s):

Computed Tomography ◽

Positive Predictive Value ◽

Predictive Value ◽

High Specificity ◽

Whole Body ◽

Cutoff Value ◽

Whole Body Ct ◽

Isolated Injury ◽

D Dimer ◽

Body Ct

Abstract Background Unnecessary whole-body computed tomography (CT) may lead to excess radiation exposure. Serum D-dimer levels have been reported to correlate with injury severity. We examined the predictive value of serum D-dimer level for identifying patients with isolated injury that can be diagnosed with selected-region CT rather than whole-body CT. Methods This single-center retrospective cohort study included patients with blunt trauma (2014–2017). We included patients whose serum D-dimer levels were measured before they underwent whole-body CT. “Isolated” injury was defined as injury with Abbreviated Injury Scale (AIS) score ≤ 5 to any of five regions of interest or with AIS score ≤ 1 to other regions, as revealed by a CT scan. A receiver operating characteristic curve (ROC) was drawn for D-dimer levels corresponding to isolated injury; the area under the ROC (AUROC) was evaluated. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for several candidate cut-off values for serum D-dimer levels. Results Isolated injury was detected in 212 patients. AUROC was 0.861 (95% confidence interval [CI]: 0.815–0.907) for isolated injury prediction. Serum D-dimer level ≤ 2.5 μg/mL was an optimal cutoff value for predicting isolated injury with high specificity (100.0%) and positive predictive value (100.0%). Approximately 30% of patients had serum D-dimer levels below this cutoff value. Conclusion D-dimer level ≤ 2.5 μg/mL had high specificity and high positive predictive value in cases of isolated injury, which could be diagnosed with selected-region CT, reducing exposure to radiation associated with whole-body CT.

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Quantitative Computed Tomography (QCT) of the Distal Forearm in Men Using a Spiral Whole-Body CT Scanner – Description of a Method and Reliability Assessment of the QCT Pro Software

Journal of Clinical Densitometry ◽

10.1016/j.jocd.2019.05.005 ◽

2020 ◽

Vol 23 (3) ◽

pp. 418-425

Author(s):

Birgit C. Hanusch ◽

Stephen P. Tuck ◽

Babitha Mekkayil ◽

Mohamed Shawgi ◽

Richard J.Q. McNally ◽

...

Keyword(s):

Computed Tomography ◽

Quantitative Computed Tomography ◽

Reliability Assessment ◽

Whole Body ◽

Distal Forearm ◽

Ct Scanner ◽

Whole Body Ct ◽

Body Ct

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A computed tomography-radiation therapy treatment planning system utilizing a whole body CT scanner

Medical Physics ◽

10.1118/1.594944 ◽

1981 ◽

Vol 8 (2) ◽

pp. 242-248 ◽

Cited By ~ 2

Author(s):

M. Edwards ◽

J. Keller ◽

G. Larsen ◽

A. Rowberg ◽

B. Sandler ◽

...

Keyword(s):

Computed Tomography ◽

Radiation Therapy ◽

Planning System ◽

Whole Body ◽

Treatment Planning System ◽

Ct Scanner ◽

Whole Body Ct ◽

Radiation Therapy Treatment Planning ◽

Therapy Treatment ◽

Body Ct

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Quantitative computed tomography (QCT) of the forearm using general purpose spiral whole-body CT scanners: Accuracy, precision and comparison with dual-energy X-ray absorptiometry (DXA)

Bone ◽

10.1016/j.bone.2009.03.669 ◽

2009 ◽

Vol 45 (1) ◽

pp. 110-118 ◽

Cited By ~ 71

Author(s):

Klaus Engelke ◽

Cesar Libanati ◽

Yu Liu ◽

Huei Wang ◽

Matt Austin ◽

...

Keyword(s):

Computed Tomography ◽

Quantitative Computed Tomography ◽

Dual Energy ◽

General Purpose ◽

Whole Body ◽

X Ray ◽

Whole Body Ct ◽

Ct Scanners ◽

Body Ct

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Screening for carotid injury in trauma patients: image quality of 16-detector-row computed tomography angiography

Acta Radiologica ◽

10.1080/02841850701422104 ◽

2007 ◽

Vol 48 (7) ◽

pp. 798-805 ◽

Cited By ~ 23

Author(s):

I. Borisch ◽

T. Boehme ◽

B. Butz ◽

O. W. Hamer ◽

S. Feuerbach ◽

...

Keyword(s):

Computed Tomography ◽

Image Quality ◽

Carotid Artery ◽

Computed Tomography Angiography ◽

Whole Body ◽

Multidetector Row Computed Tomography ◽

Trauma Patients ◽

Whole Body Ct ◽

Body Ct

Background: The introduction of multidetector-row computed tomography (MDCT) has revolutionized the initial management of multiply injured patients. This technology has the potential to improve the imaging of traumatic vascular injuries. Purpose: To evaluate the quality of multidetector-row computed tomography angiography (MDCTA) of the carotid arteries in the setting of a routine whole-body trauma scan. Material and Methods: 87 trauma patients underwent a routine whole-body CT scan in a 16-detector-row scanner including an MDCTA with a reconstructed axial slice thickness of 3 mm. Images were reviewed by three experienced radiologists with emphasis on image quality. Contrast density, severity, and origin of artifacts and the occurrence of vessel lesions were assessed for different vessel segments. Results: 3642 separate vessel segments were evaluated. Contrast density was rated good or sufficient for diagnosis in 99.8%. A total of 67.3% of vessel segments were free of artifacts, while 27.9% of vessel segments showed minor artifacts not impairing diagnostic evaluation. Clinically relevant artifacts obscuring a vessel segment occurred in 4.7% and were mostly caused by dental hardware. Four dissections of the internal carotid artery were diagnosed by all three radiologists. Conclusion: As a rapid screening test for blunt carotid artery injury, integration of MDCTA in the routine imaging workup of trauma patients utilizing a whole-body CT trauma scan is possible and practicable. Image quality is mostly sufficient for diagnosis, but impaired in a few cases by artifacts deriving primarily from dental hardware.

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Serum D-dimer level as a biomarker for identifying patients with isolated injury to prevent unnecessary whole-body computed tomography in blunt trauma care

10.21203/rs.3.rs-64009/v2 ◽

2020 ◽

Author(s):

Rakuhei Nakama ◽

Ryo Yamamoto ◽

Yoshimitsu Izawa ◽

Keiichi Tanimura ◽

Takashi Mato

Keyword(s):

Computed Tomography ◽

Positive Predictive Value ◽

Predictive Value ◽

High Specificity ◽

Whole Body ◽

Cutoff Value ◽

Whole Body Ct ◽

Isolated Injury ◽

D Dimer ◽

Body Ct

Abstract Background Unnecessary whole-body computed tomography (CT) may lead to excess radiation exposure. Serum D-dimer levels have been reported to correlate with injury severity. We examined the predictive value of serum D-dimer level for identifying patients with isolated injury that can be diagnosed with selected-region CT rather than whole-body CT.Methods This single-center retrospective cohort study included patients with blunt trauma (2014–2017). We included patients whose serum D-dimer levels were measured before they underwent whole-body CT. “Isolated” injury was defined as injury with Abbreviated Injury Scale (AIS) score ≤ 5 to any of five regions of interest or with AIS score ≤ 1 to other regions, as revealed by a CT scan. A receiver operating characteristic curve (ROC) was drawn for D-dimer levels corresponding to isolated injury; the area under the ROC (AUROC) was evaluated. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for several candidate cut-off values for serum D-dimer levels. Results Isolated injury was detected in 212 patients. AUROC was 0.861 (95% confidence interval [CI]: 0.815–0.907) for isolated injury prediction. Serum D-dimer level ≤ 2.5 μg/mL was an optimal cutoff value for predicting isolated injury with high specificity (100.0 %) and positive predictive value (100.0 %). Approximately 30% of patients had serum D-dimer levels below this cutoff value.Conclusion D-dimer level ≤ 2.5 μg/mL had high specificity and high positive predictive value in cases of isolated injury, which could be diagnosed with selected-region CT, reducing exposure to radiation associated with whole-body CT.

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Patient-specific biomechanical model as whole-body CT image registration tool

Medical Image Analysis ◽

10.1016/j.media.2014.12.008 ◽

2015 ◽

Vol 22 (1) ◽

pp. 22-34 ◽

Cited By ~ 14

Author(s):

Mao Li ◽

Karol Miller ◽

Grand Roman Joldes ◽

Barry Doyle ◽

Revanth Reddy Garlapati ◽

...

Keyword(s):

Image Registration ◽

Biomechanical Model ◽

Whole Body ◽

Patient Specific ◽

Ct Image ◽

Whole Body Ct ◽

Body Ct

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Serum D-dimer level as a biomarker for identifying patients with isolated injury to prevent unnecessary whole-body computed tomography in blunt trauma care

10.21203/rs.3.rs-64009/v1 ◽

2020 ◽

Author(s):

Rakuhei Nakama ◽

Ryo Yamamoto ◽

Yoshimitsu Izawa ◽

Keiichi Tanimura ◽

Takashi Mato

Keyword(s):

Computed Tomography ◽

Positive Predictive Value ◽

Predictive Value ◽

High Specificity ◽

Whole Body ◽

Cutoff Value ◽

Whole Body Ct ◽

Isolated Injury ◽

D Dimer ◽

Body Ct

Abstract Background Unnecessary whole-body computed tomography (CT) may lead to excess radiation exposure. Serum D-dimer levels have been reported to correlate with injury severity. We examined the predictive value of serum D-dimer level for identifying patients with isolated injury that can be diagnosed with selected-region CT rather than whole-body CT.Methods This single-center retrospective cohort study included patients with blunt trauma (2014–2017). We included patients whose serum D-dimer levels were measured before they underwent whole-body CT. “Isolated” injury was defined as injury with Abbreviated Injury Scale (AIS) score ≤ 5 to any of five regions of interest or with AIS score ≤ 1 to other regions, as revealed by a CT scan. A receiver operating characteristic curve (ROC) was drawn for D-dimer levels corresponding to isolated injury; the area under the ROC (AUROC) was evaluated. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for several candidate cut-off values for serum D-dimer levels.Results Isolated injury was detected in 212 patients. AUROC was 0.861 (95% confidence interval [CI]: 0.815–0.907) for isolated injury prediction. Serum D-dimer level ≤ 2.5 µg/mL was an optimal cutoff value for predicting isolated injury with high specificity (100.0%) and positive predictive value (100.0%). Approximately 30% of patients had serum D-dimer levels below this cutoff value.Conclusion D-dimer level ≤ 2.5 µg/mL had high specificity and high positive predictive value in cases of isolated injury, which could be diagnosed with selected-region CT, reducing exposure to radiation associated with whole-body CT.

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Excess of radiation burden for young testicular cancer patients using automatic exposure control and contrast agent on whole-body computed tomography imaging

Radiology and Oncology ◽

10.1515/raon-2017-0012 ◽

2017 ◽

Vol 51 (2) ◽

pp. 235-240

Author(s):

Hannele Niiniviita ◽

Jarmo Kulmala ◽

Tuukka Pölönen ◽

Heli Määttänen ◽

Hannu Järvinen ◽

...

Keyword(s):

Computed Tomography ◽

Testicular Cancer ◽

Contrast Agent ◽

Cancer Patients ◽

Whole Body ◽

Exposure Control ◽

Automatic Exposure Control ◽

Whole Body Ct ◽

Patient Size ◽

Body Ct

Abstract Background The aim of the study was to assess patient dose from whole-body computed tomography (CT) in association with patient size, automatic exposure control (AEC) and intravenous (IV) contrast agent. Patients and methods Sixty-five testicular cancer patients (mean age 28 years) underwent altogether 279 whole-body CT scans from April 2000 to April 2011. The mean number of repeated examinations was 4.3. The GE LightSpeed 16 equipped with AEC and the Siemens Plus 4 CT scanners were used for imaging. Whole-body scans were performed with (216) and without (63) IV contrast. The ImPACT software was used to determine the effective and organ doses. Results Patient doses were independent (p < 0.41) of patient size when the Plus 4 device (mean 7.4 mSv, SD 1.7 mSv) was used, but with the LightSpeed 16 AEC device, the dose (mean 14 mSv, SD 4.6 mSv) increased significantly (p < 0.001) with waist cirfumference. Imaging with the IV contrast agent caused significantly higher (13% Plus 4, 35% LightSpeed 16) exposure than non-contrast imaging (p < 0.001). Conclusions Great caution on the use of IV contrast agent and careful set-up of the AEC modulation parameters is recommended to avoid excessive radiation exposure on the whole-body CT imaging of young patients.

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