scholarly journals Differentiation of Rebound and Lymphoid Thymic Hyperplasia from Anterior Mediastinal Tumors with Dual-Echo Chemical-Shift MR Imaging in Adulthood: Reliability of the Chemical-Shift Ratio and Signal Intensity Index

Radiology ◽  
2015 ◽  
Vol 274 (1) ◽  
pp. 238-249 ◽  
Author(s):  
Adriano M. Priola ◽  
Sandro M. Priola ◽  
Giovannino Ciccone ◽  
Andrea Evangelista ◽  
Aldo Cataldi ◽  
...  
Keyword(s):  
Chemical Shift ◽  
Mr Imaging ◽  
Signal Intensity ◽  
Thymic Hyperplasia ◽  
Mediastinal Tumors ◽  
Intensity Index ◽  
Dual Echo

Could we assess the functional status, of hormone secreting, or non-secreting of the adrenal masses regarding their Magnetic Resonance Imaging (MRI) characteristics?

2021 ◽  
Vol 22 ◽  
Author(s):  
Gamze Akkus ◽  
Ferhat Piskin ◽  
Barış Karagun ◽  
Murat Sert ◽  
Mehtap Evran ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Chemical Shift ◽  
Functional Status ◽  
Signal Intensity ◽  
Adrenal Mass ◽  
Resonance Imaging ◽  
Intensity Index ◽  
Adrenal Masses ◽  
Magnetic Resonance Imaging Mri

Background: Diagnostic imaging techniques including magnetic resonance imaging (MRI) should also perform on all patients with incidentalomas. However, there is a limited study whether the quantitative measurements (signal intensity index, adrenal to spleen ratio) in MRI could predict the functional status of adrenal adenomas. Material-Method: Between 2015-2020; 404 patients (265 females, 139 males) with adrenal mass who were referred to the university hospital for further investigation were included. After detailed diagnostic hormonal evaluation, all patients underwent MRI 1.5 T device (Signa, GE Medical Systems; Milwaukee, USA). The signal intensities of the adrenal lesions on T2W images were qualitatively evaluated and noted as homogenous or heterogeneous in comparison with the liver signal intensity (SI). A chemical-shift SI index and chemical shift adrenal-to-spleen SI ratio were also calculated. Results: While 331(81.9%) of the patients had nonfunctional adrenal mass, the rest of them (n=73, 18.1%) were patients with functional (autonomous cortisol secretion-ACS, cushing syndrome-CS, pheochromocytoma, primary hyperaldosteronism-PA) adrenal masses. In phase vs phase values of patients with NFAI, Pheo(n=17), ACS (n=30), CS (n=11), and PA (n=15) were 474.04±126.7 vs 226.6±132.4, 495.3±182.8 vs 282.17±189.1, 445.2±134.8 vs 203.3±76.2, 506.8±126.5 vs 212.2±73.6 and 496.2±147.5 vs 246.6±102.1, respectively. Mean signal intensity index (SII) and adrenal to spleen ratio (ASR) of all groups (NFAI, Pheo, ACS, CS, PA) were 52.0±24.8 and 0.51, 44.9±22.5 and 0.55, 49.5±24.5 and 0.53, 56.2±16.4 and 0.43, 47.6±25.1 and 0.54, respectively. Based the current accepted measurements in the case of ASR and SII, all lesions were similar and shown as fat rich adenomas (p*= 0.552, p** = 0.45). Conclusion: The quantitative assessment (SII, ASR) of intracellular lipids in an incidentally discovered adrenal tumour could only help distinguish adrenal masses in case of adenomas or non-adenomas As initial diagnostic evaluation, clinical and laboratory assessment ,to distinguish hormone secretion, should be taken in all patients with adrenal incidentalomas.

scholarly journals Qualitative Heterogeneous Signal Drop on Chemical Shift (CS) MR Imaging: Correlative Quantitative Analysis between CS Signal Intensity Index and Contrast Washout Parameters Using T1-Weighted Sequences

Tomography ◽  
2021 ◽  
Vol 7 (4) ◽  
pp. 961-971
Author(s):  
Arnaldo Stanzione ◽  
Francesco Verde ◽  
Roberta Galatola ◽  
Valeria Romeo ◽  
Raffaele Liuzzi ◽  
...  
Keyword(s):  
Chemical Shift ◽  
Signal Intensity ◽  
Characteristic Analysis ◽  
Intensity Index ◽  
Quantitative Parameters ◽  
Group 3 ◽  
Group 2 ◽  
Post Hoc ◽  
Weighted Sequences ◽  
Group 1

The aim of this study was to calculate MRI quantitative parameters extracted from chemical-shift (CS) and dynamic contrast-enhanced (DCE) T1-weighted (T1-WS) images of adrenal lesions (AL) with qualitative heterogeneous signal drop on CS T1-WS and compare them to those of AL with homogeneous or no signal drop on CS T1-WS. On 3 T MRI, 65 patients with a total of 72 AL were studied. CS images were qualitatively assessed for grouping AL as showing homogeneous (Group 1, n = 19), heterogeneous (Group 2, n = 23), and no (Group 3, n = 30) signal drop. Histopathology or follow-up data served as reference standard to classify AL. ROIs were drawn both on CS and DCE images to obtain adrenal CS signal intensity index (ASII), absolute (AWO), and relative washout (RWO) values. Quantitative parameters (QP) were compared with ANOVA analysis and post hoc Dunn’s test. The performance of QP to classify AL was assessed with receiver operating characteristic analysis. CS ASII values were significantly different among the three groups (p < 0.001) with median values of 71%, 53%, and 3%, respectively. AWO/RWO values were similar in Groups 1 (adenomas) and 2 (benign AL) but significantly (p < 0.001) lower in Group 3 (20 benign AL and 10 malignant AL). With cut-offs, respectively, of 60% (Group 1 vs. 2), 20% (Group 2 vs. 3), and 37% (Group 1 vs. 3), CS ASII showed areas under the curve of 0.85, 0.96, and 0.93 for the classification of AL, overall higher than AWO/RWO. In conclusion, AL with qualitative heterogeneous signal drop at CS represent benign AL with QP by DCE sequence similar to those of AL with homogeneous signal drop at CS, but different to those of AL with no signal drop at CS; ASII seems to be the only quantitative parameter able to differentiate AL among the three different groups.

scholarly journals Phase Shift MRI in Assessement of Vertebral Compression Fracture: Trial for a New Scoring System

2020 ◽  
Author(s):  
Khaled Matrawy ◽  
Nadia Abdel Fattah ◽  
Abdel Aziz ElNekidy ◽  
Mohamed Abdel Gawad ◽  
Alaa Elnaggar ◽  
...  
Keyword(s):  
Chemical Shift ◽  
Mr Imaging ◽  
Signal Intensity ◽  
Scoring System ◽  
Diffusion Weighted Imaging ◽  
Vertebral Compression Fracture ◽  
Compression Fracture ◽  
Vertebral Compression Fractures ◽  
Diffusion Weighted ◽  
New Scoring

Abstract PurposeTo assess the value of in /opposed-phase quantitative chemical shift MRI in differentiating malignant from benign vertebral compression fractures (VCF).Patients and methodsTwenty patients (8 men), mean age 56 years, with low back and radiological proof of VCF were included in the study. MRI of spine with standard conventional sequences and special chemical shift sequence (in/opposed phase) as well as diffusion weighted imaging were performed (at 1.5 Tesla). Quantitative image analysis of regions of interest (ROI) on the abnormal marrow in the compressed (study group) and related normal vertebra in same patient (control group) was done in each patient. The signal intensity ratio (SIR) of the marrow was determined by dividing the mean signal intensity on the opposed-phase and in-phase images was performed.ResultsMean SIR of benign VCF [0.6 ± 0.27 (range 0.23–1.1)] was significantly lower than malignant VCF values [1.115 ± 0.14 (range 0.87–1.45)] (p < 0.0001, ROC 0.97). The optimal SIR cutoff value for separating benign and malignant VCF was found to be 0.9 with a calculated sensitivity of 91.5%, specificity of 87.5% and accuracy of 90%. We also found a cut-off value of 0.9, to be a statistically significant in differentiating benign from malignant causes of VCF. If SIR of 0.91 as a cutoff is applied, with >0.91 indicating malignant result and <0.91 defined as a benign result.ConclusionQuantitative chemical shift MR imaging could be a valuable addition to standard MR imaging techniques in differentiating benign from malignant vertebral compression fracture. We designed a new scoring system based on conventional MRI, in/opposed phase chemical shift and diffusion weighted imaging. The new scoring system may be a useful tool and add value in the diagnosis of compression vertebral fractures.

Sign in / Sign up

Export Citation Format

Share Document