The Calibration Problem in Liver Iron Susceptometry

Background and Purpose: Quantification of hepatic virtual iron content (VIC) by using Multidetector Dual Energy Computed Tomography (DECT) has been recently investigated since this technique could offer a good compromise between accuracy and non-invasiveness for liver iron content quantification. The aim of our study is to investigate differences in VIC at different DECT time points (namely baseline and arterial, venous and tardive phases), identifying the most reliable and also exploring the underlying temporal trend of these values. Materials and Methods: Eleven patients who underwent DECT examination and were characterized by low liver fat content were included in this retrospective study. By using the Syngo.via Frontier–DE IronVNC tool, regions of interest (ROI) were placed on the VIC images at 3 hepatic levels, both in left and right liver lobes, at each DECT time point. Friedman’s test followed by Bonferroni-adjusted Wilcoxon signed-rank test for post-hoc analysis was performed to assess differences between DECT timepoints. Page’s L test was performed to test the temporal trend of VIC across the 4 examined timepoints. Results: For both liver lobes, Friedman’s test followed by Bonferroni-adjusted Wilcoxon signed-rank test revealed that VIC values differed significantly when extracted from ROIs placed at the 4 different timepoints. The Page’s L test for multiple comparison revealed a significant growing trend for VIC, from baseline acquisition to the fourth and last time point post-contrast agent injection. Conclusions: The extraction of hepatic VIC in healthy subjects was found to be significantly influenced by the DECT time point chosen for the extrapolation of the VIC values.

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The Calibration Problem in Inertial Navigation

Journal of Mathematical Sciences ◽

10.1007/s10958-021-05272-y ◽

2021 ◽

Author(s):

N. B. Vavilova ◽

I. A. Vasineva ◽

A. A. Golovan ◽

A. V. Kozlov ◽

I. A. Papusha ◽

...

Keyword(s):

Inertial Navigation ◽

Calibration Problem

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Analysis of liver iron concentration in an elderly female undergoing hemodialysis with calcific uremic arteriolopathy does not support the role of iron overload in calciphylaxis: lesson for the clinical nephrologist

Journal of Nephrology ◽

10.1007/s40620-020-00904-z ◽

2021 ◽

Author(s):

Guy Rostoker ◽

Patricia Senet ◽

Fanny Lepeytre ◽

Mireille Griuncelli ◽

Christelle Loridon ◽

...

Keyword(s):

Iron Overload ◽

Iron Concentration ◽

Liver Iron Concentration ◽

Liver Iron ◽

Elderly Female ◽

Calcific Uremic Arteriolopathy

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MRI evaluation of hepatic and cardiac iron burden in pediatric thalassemia major patients: spectrum of findings by T2*

Egyptian Journal of Radiology and Nuclear Medicine ◽

10.1186/s43055-019-0044-5 ◽

2019 ◽

Vol 50 (1) ◽

Cited By ~ 1

Author(s):

Samar M. Shehata ◽

Mohamed I. Amin ◽

El Sayed H. Zidan

Keyword(s):

Chelation Therapy ◽

Statistical Significance ◽

Iron Chelation ◽

Good Method ◽

Thalassemia Major ◽

Local Magnetic Field ◽

Cardiac Complications ◽

Liver Iron ◽

Cross Sectional ◽

Signal Decay

Abstract Background Iron deposition distorts the local magnetic field exerting T2* signal decay. Biopsy, serum ferritin, echocardiography are not reliable to adjust iron chelation therapy. Quantified MRI signal decay can replace biopsy to diagnose iron burden, guide treatment, and follow up. The objective of this study is to evaluate the role of T2* in quantification of the liver and heart iron burden in thalassemia major patients. This cross-sectional study included 44 thalassemia patients who were referred to MRI unit, underwent T2* MRI. Results Twenty-one male (47.7%) and 23 female (52.3%) were included (age range 6–15 years, mean age 10.9 ± 2.9 years). Patients with excess hepatic iron show the following: 11/40 (27.5%) mild, (13/40) 32.5% moderate, and (14/40) 35% severe liver iron overload. High statistical significance regarding association between LIC and liver T2* (p = 0.000) encountered. Cardiac T2* values showed no relationship with age (p = 0.6). Conclusion T2* is a good method to quantify, monitor hepatic and myocardial iron burden, guiding chelation therapy and prevent iron-induced cardiac complications.

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