scholarly journals Diagnostic Accuracy of Quantitative Imaging Biomarkers in the Differentiation of Benign and Malignant Vertebral Lesions

2021 ◽  
Author(s):  
Frederic Carsten Schmeel ◽  
Simon Jonas Enkirch ◽  
Julian Alexander Luetkens ◽  
Anton Faron ◽  
Nils Lehnen ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Diagnostic Performance ◽  
Spin Echo ◽  
Quantitative Imaging ◽  
Imaging Biomarkers ◽  
Proton Density ◽  
Single Shot ◽  
Apparent Diffusion ◽  
Malignant Lesions ◽  
Magnetic Resonance Imaging Mri

Abstract Purpose To compare and combine the diagnostic performance of the apparent diffusion coefficient (ADC) derived from diffusion-weighted imaging (DWI) and proton density fat fraction (PDFF) derived from chemical-shift encoding (CSE)-based water-fat magnetic resonance imaging (MRI) for distinguishing benign and malignant vertebral bone marrow lesions (VBML). Methods A total of 55 consecutive patients with 53 benign (traumatic, inflammatory and primary) and 36 malignant (metastatic and hematologic) previously untreated VBMLs were prospectively enrolled in this IRB-approved study and underwent sagittal DWI (single-shot spin-echo echo-planar with multi-slice short TI inversion recovery fat suppression) and CSE-based MRI (gradient-echo 6‑point modified Dixon) in addition to routine clinical spine MRI at 1.5 T or 3.0 T. Diagnostic reference standard was established according to histopathology or imaging follow-up. The ADC = ADC (0, 800) and PDFF = fat / (water + fat) were calculated voxel-wise and examined for differences between benign and malignant lesions. Results The ADC and PDFF values of malignant lesions were significantly lower compared to benign lesions (mean ADC 861 × 10−6 mm2/s vs. 1323 × 10−6 mm2/s, p < 0.001; mean PDFF 3.1% vs. 28.2%, p < 0.001). The areas under the curve (AUC) and diagnostic accuracies were 0.847 (p < 0.001) and 85.4% (cut-off at 1084.4 × 10−6 mm2/s) for ADC and 0.940 (p < 0.001) and 89.9% for PDFF (cut-off at 7.8%), respectively. The combined use of ADC and PDFF improved the diagnostic accuracy to 96.6% (malignancy if ADC ≤ 1118.2 × 10−6 mm2/s and PDFF ≤ 20.0%, otherwise benign). Conclusion Quantitative evaluation of both ADC and PDFF was useful in differentiating benign VBMLs from malignancy. The combination of ADC and PDFF improved the diagnostic performance and yielded high diagnostic accuracy for the differentiation of benign and malignant VBMLs.

scholarly journals Diffusion Weighted MR Imaging of Primary and Recurrent Middle Ear Cholesteatoma: An Assessment by Readers with Different Expertise

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
A. Elefante ◽  
M. Cavaliere ◽  
C. Russo ◽  
G. Caliendo ◽  
M. Marseglia ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Middle Ear ◽  
Spin Echo ◽  
Interrater Agreement ◽  
Lower Probability ◽  
Kappa Statistics ◽  
Single Shot ◽  
Predictive Values ◽  
Diffusion Weighted ◽  
Middle Ear Cholesteatoma

Introduction and Purpose. Diffusion weighted imaging (DWI) has been proven to be valuable in the diagnosis of middle ear cholesteatoma. The aims of our study were to evaluate the advantage of multi-shot turbo spin echo (MSh TSE) DWI compared to single-shot echo-planar (SSh EPI) DWI for the diagnosis of cholesteatoma.Material and Methods. Thirty-two patients with clinical suspicion of unilateral cholesteatoma underwent preoperative MRI (1.5T) with SSh EPI and MSh TSE. Images were separately analyzed by 4 readers with different expertise to confirm the presence of cholesteatoma. Sensitivity, specificity, diagnostic accuracy, and positive (PPV) and negative predictive values (NPV) were assessed for each observer and interrater agreement was assessed using kappa statistics. Diagnosis was obtained at surgery.Results. Overall MSh TSE showed higher diagnostic accuracy and lower negative predictive value (NPV) compared to conventional SSh EPI. Interreader agreement between the observers revealed the superiority of MSh TSE compared to SSh EPI. Interrater agreement among all the four observers was higher by using MSh TSE compared to SSh EPI.Conclusion. Our findings suggest that MSh TSE DWI has higher sensitivity for detection of cholesteatoma and lower probability of misdiagnosis. MSh TSE DWI is useful in guiding less experienced observers to the diagnosis.

Single-shot diffusion-weighted echo-planar imaging of normal and cirrhotic livers using a phased-array multicoil

1998 ◽  
Vol 39 (4) ◽  
pp. 440-442 ◽  
Author(s):  
Y. Amano ◽  
T. Kumazaki ◽  
M. Ishihara
Keyword(s):  
Phased Array ◽  
Spin Echo ◽  
B Value ◽  
Echo Planar Imaging ◽  
Single Shot ◽  
Planar Imaging ◽  
Apparent Diffusion Coefficients ◽  
Diffusion Weighted ◽  
Apparent Diffusion ◽  
Echo Planar

Single-shot spin-echo diffusion-weighted echo-planar imaging using a phased-array multicoil was performed to distinguish between normal and cirrhotic livers. Sets of 6 images with different b-values were acquired with breathholding. Significant differences were observed between controls and cirrhosis cases in the signal ratios when the b-value was 383 s/mm2, and apparent diffusion coefficients.

scholarly journals Static T2w MRU in Noncalcular Urinary Obstruction: Comparison of Its Two Techniques

2008 ◽  
Vol 8 ◽  
pp. 454-462 ◽  
Author(s):  
Mohamed Abou El-Ghar ◽  
Ahmed Shokeir ◽  
Huda Rafaie ◽  
Tarek El-Diasty
Keyword(s):  
Diagnostic Accuracy ◽  
Spin Echo ◽  
Maximum Intensity Projection ◽  
Urinary Obstruction ◽  
Fast Spin Echo ◽  
Renal Unit ◽  
Single Shot ◽  
Ureteric Obstruction ◽  
Section Technique ◽  
Prostatic Tumor

The purpose of this study was to compare the diagnostic accuracy of T2-weighted (T2w) MR urography (MRU) techniques — the standard MRU using fast spin echo (FSE) and postprocessing maximum intensity projection (MIP) and the single-shot MRU — in the diagnosis of ureteric obstruction in patients with noncalcular urinary obstruction. The study included 150 patients admitted to our center between January 2005 and December 2006. There were 203 renal units with noncalcular obstruction; 53 patients had bilateral obstruction. Patients with calcular obstruction were excluded. There were 85 males and 65 females with a mean age of 50 (range: 5–83) years. All patients were examined with static MRU using both single-shot (thick slab) and multisection MRU. Using single-shot MRU, we obtained images at the direct coronal and oblique coronal, as well as sagittal, planes for each renal unit. Postprocessing MIP for the standard coronal heavy T2 source images to obtain coronal and oblique images was done. Among the obstructed 203 units, the intrinsic causes were present in 157 units (151 were stricture and six were ureteric tumors), while the extrinsic causes were present in 46 units (35 bladder tumor, four ureterocele, five retroperitoneal fibrosis, one prostatic tumor, and one local pelvic recurrence after radical cystectomy for bladder cancer). The overall accuracy of single-shot MRU was 89% and was 93% for the multisection MRU in cases of intrinsic ureteric obstruction, while in cases of extrinsic obstruction, it was 20% for single-shot MRU and 96% for multisection MRU. T2w static MRU is a very useful technique in diagnosing noncalcular ureteric obstruction. Multisection MRU has a high diagnostic accuracy and reliability over that of the single-shot technique. The single-section technique is very rapid and useful in diagnosing ureteric stricture so it could be used as a localizer, while multisection images with postprocessing MIP is mandatory, especially in cases of suspected ureteric tumors or extraureteric causes.

scholarly journals Feasibility of synthetic MRI in knee imaging in routine practice

2018 ◽  
Vol 7 (5) ◽  
pp. 205846011876968 ◽  
Author(s):  
Sana Boudabbous ◽  
Angeliki Neroladaki ◽  
Ilias Bagetakos ◽  
Marion Hamard ◽  
Bénédicte MA Delattre ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Cruciate Ligament ◽  
Quantitative Imaging ◽  
Proton Density ◽  
Routine Practice ◽  
Synthetic Sequence ◽  
Magnetic Resonance Imaging Mri ◽  
Anterior Cruciate ◽  
Knee Imaging ◽  
Synthetic Mri

Background Synthetic magnetic resonance (MR) is a method allowing reduction of examination time and access to quantitative imaging. Purpose This study sought to assess the image quality and diagnostic accuracy of synthetic magnetic resonance imaging (MRI) compared to standard MRI in patients with knee pain. Material and Methods In total, 22 patients underwent standard 1.5 knee MRI with an added synthetic sequence. Quantitative T1, T2, and proton density (PD) images were generated synthetically; T1, PD, and short tau inversion recovery (STIR) weighted images were created with chosen echo time (TE), repetition time (TR), and inversion time (TI). Two blinded musculoskeletal radiologists evaluated the overall sequence quality, visualization of anatomic structures, and presence of artifacts using a 3-point score. Results The synthetic sequence was acquired in 39% less time than the conventional MRI. Synthetic PD, T1, and STIR images were rated fair (2%, 5%, and 2%, respectively) or good quality (98%, 95%, and 98%, respectively), despite the presence of popliteal artery artifacts. Cartilage and meniscus were well visualized in all cases. Anterior cruciate ligament visualization was rated poor in 7%, 14%, and 30% of PD, STIR, and T1 images, respectively. Conclusion Our pilot study confirmed the feasibility of synthetic MRI in knee examinations, proving faster and achieving appropriate quality and good diagnostic confidence.

scholarly journals MRI of Uveal Melanoma

Cancers ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 377 ◽  
Author(s):  
Teresa Ferreira ◽  
Lorna Grech Fonk ◽  
Myriam Jaarsma-Coes ◽  
Guido van Haren ◽  
Marina Marinkovic ◽  
...  
Keyword(s):  
Uveal Melanoma ◽  
Spin Echo ◽  
Functional Images ◽  
Tissue Contrast ◽  
Mri Protocol ◽  
3 Tesla Mri ◽  
Malignant Lesions ◽  
Magnetic Resonance Imaging Mri ◽  
Extension Evaluation

Uveal Melanoma (UM) is the most common primary malignant ocular tumor. The high soft tissue contrast and spatial resolution, and the possibility of generating 3D volumetric and functional images, make Magnetic Resonance Imaging (MRI) a valuable diagnostic imaging technique in UM. Current clinical MRI protocols, however, are not optimized for UM and therefore lack the quality for accurate assessments. We therefore developed a dedicated protocol at a 3 Tesla MRI, using an eye coil, consisting of multi-slice 2D sequences, different isotropic sequences and diffusion and perfusion-weighted images. This protocol was prospectively evaluated in 9 uveal melanoma patients. The multi-slice 2D sequences had the highest in-plane resolution, being the most suited for lesion characterization and local extension evaluation. The isotropic 3D Turbo-Spin Echo (TSE) sequences were the most suitable for accurate geometric measurements of the tumor and are therefore important for therapy planning. Diffusion and perfusion-weighted images aid in differentiating benign from malignant lesions and provide quantitative measures on tumor hemodynamics and cellularity, which have been reported to be effective in predicting and assessing treatment outcome. Overall, this dedicated MRI protocol provides high-quality imaging of UM, which can be used to improve its diagnosis, treatment planning, and follow-up.

scholarly journals Disparate Volumetric Fluid Shifts Across Cerebral Tissue Compartments with Two Different Anesthetics

2020 ◽  
Author(s):  
Burhan O. Ozturk ◽  
Brittany Monte ◽  
Sunil Koundal ◽  
Feng Dai ◽  
Helene Benveniste ◽  
...  
Keyword(s):  
Fluid Transport ◽  
Female Rats ◽  
Proton Density ◽  
Sprague Dawley ◽  
Cerebral Tissue ◽  
Physiological Variables ◽  
Diffusion Weighted Images ◽  
Apparent Diffusion ◽  
Magnetic Resonance Imaging Mri ◽  
Tissue Compartments

Abstract Background: Large differences in glymphatic system transport - similar in magnitude to those of the sleep/wake cycle - have been observed during anesthesia with dexmedetomidine supplemented with low dose isoflurane (DEXM-I) in comparison to isoflurane (ISO). However, the biophysical and bioenergetic tissue status underlying glymphatic transport differences between anesthetics remains undefined. To further understand biophysical characteristics underlying these differences we investigated volume status across cerebral tissue compartments, water diffusivity, and T2* values in rats anesthetized with DEXM-I in comparison to ISO. Methods: Using a crossover study design, a group of 12 Sprague Dawley female rats underwent repetitive magnetic resonance imaging (MRI) under ISO and DEXM-I. Physiological parameters were continuously measured. MRI included a proton density weighted (PDW) scan to investigate cerebrospinal fluid (CSF) and parenchymal volumetric changes, a multigradient echo scan (MGE) to calculate T2* maps as a measure of ‘bioenergetics’, and a diffusion scan to quantify the apparent diffusion coefficient (ADC). Results: The heart rate was lower with DEXM-I in comparison to ISO, but all other physiological variables were similar across scans and groups. The PDW images revealed a 1% parenchymal volume increase with ISO compared to DEXM-I comprising multiple focal tissue areas scattered across the forebrain. In contrast, with DEXM-I the CSF compartment was enlarged by ~6% in comparison to ISO at the level of the basal cisterns and peri-arterial conduits which are main CSF influx routes for glymphatic transport. The T2* maps showed brain-wide increases in T2* in ISO compared to DEXM-I rats. Diffusion-weighted images yielded no significant differences in ADCs across the two anesthesia groups. Conclusions: We demonstrated CSF volume expansion with DEXM-I (in comparison to ISO) and parenchymal (GM) expansion with ISO (in comparison to DEXM-I), which may explain the differences in glymphatic transport. We propose that tissue enlargements observed with ISO represent clusters of cellular ‘swelling’ imposing hydraulic resistance for solute and fluid transport, thereby explaining the reduced glymphatic transport with ISO compared to DEXM-I. The T2* changes in ISO are suggestive of an increased bioenergetic state associated with excess cellular firing/bursting when compared to DEXM-I.

scholarly journals Diagnostic Performance and Reliability of Non-Enhanced Imaging Characterization Quotients for the Differentiation of Infectious and Malignant Pulmonary Nodules in Hematological Patients Using 3T MRI

2019 ◽  
Vol 192 (04) ◽  
pp. 327-334 ◽  
Author(s):  
Sebastian Niko Nagel ◽  
Damon Kim ◽  
Tatjana Wylutzki ◽  
Ingo G. Steffen ◽  
Stefan Schwartz ◽  
...  
Keyword(s):  
Diagnostic Performance ◽  
Spin Echo ◽  
Intraclass Correlation ◽  
Pulmonary Nodules ◽  
Fast Spin Echo ◽  
Single Shot ◽  
Hematological Patients ◽  
Enhanced Imaging ◽  
Signal Intensities ◽  
Imaging Characterization

Purpose To evaluate the diagnostic performance and reliability of non-enhanced imaging characterization quotients (NICQs) derived from magnetic resonance imaging (MRI) in the differential diagnosis of pulmonary nodules in hematological patients. Materials and Methods A total of 83 lesions in 45 consecutive hematological patients were analyzed (10 bacterial pneumonias, 16 fungal pneumonias, 19 pulmonary lymphoma manifestations). The MRI protocol included T2-weighted single-shot fast spin echo (FSE) and T1-weighted gradient echo (GRE) sequences. T2-based T2-NICQmean and T2-NICQ90th were calculated from signal intensities measured in the lesion, muscle, and fat ((SILesion – SIMuscle)/(SIFat – SIMuscle) * 100), and simple T1-based T1-Qmean from signal intensities of the lesion and muscle (SILesion/SIMuscle). Images were read by one radiologist with > 7 years and one with 1 year of experience. For statistical evaluation the Kruskal-Wallis or Mann-Whitney U-test, receiver operating characteristic (ROC) analysis with calculation of areas under the curve (AUC), and intraclass correlation coefficients (ICCs) were used. Results Medians of T2-NICQs differed significantly when comparing infectious lesions and lymphoma manifestations in general (T2-NICQmean 20.33 vs. 10.14; T2-NICQ90th 34.96 vs. 25.52) or fungal lesions and lymphoma manifestations in particular (T2-NICQmean 19.00 vs. 10.14; T2-NICQ90th 34.49 vs. 25.25). The AUCs for T2-NICQs on the per-patient level ranged from 0.73 to 0.79. ICCs were at least > 0.85, except for intrarater testing of T2-NICQ90th (0.79). Conclusion The overall diagnostic performance of T2-NICQs is adequate for differentiating infectious and fungal lesions from lymphoma manifestations. The results show good to excellent intra- and interrater agreement. We therefore consider NICQs helpful in the diagnostic workup of pulmonary nodules in hematological patients. Key points:  Citation Format

Improved visualisation of cervix applicators for magnetic resonance-only-guided brachytherapy planning

2014 ◽  
Vol 13 (2) ◽  
pp. 159-165
Author(s):  
Gary P. Liney ◽  
Jenny E. Marsden ◽  
Carl J. Horsfield ◽  
Tom Murray ◽  
David J. Manton ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Magnetic Resonance ◽  
Soft Tissues ◽  
Spin Echo ◽  
Proton Density ◽  
Tissue Equivalent ◽  
Spin Echo Sequence ◽  
Otsu’S Method ◽  
Magnetic Resonance Imaging Mri ◽  
Dual Echo

AbstractObjectivesCurrent guidelines for image-guided cervical cancer brachytherapy planning recommend both computed tomography (CT) and magnetic resonance imaging (MRI) for adequate visualisation of the applicator and soft tissues, respectively. MRI-only planning would be ideal as it would save time within the patient pathway and avoid the concomitant CT exposures. However, applicator visualisation on MRI is usually achieved using fluid-filled fiducial marker tubes, which can be awkward to use and suffer from unwanted air bubble artefacts. Therefore, a new fiducial-free imaging technique was developed.MethodsA dual echo time (TE) turbo spin echo sequence was used, at 1·5 T, to provide both T2-weighted images (100 ms TE) for tissue visualisation and strongly proton density-weighted images (17 ms TE) for improved applicator visualisation. In-house software was used to automatically segment the applicator in the short TE images (using Otsu's method) and transfer the information to the long TE images to provide a single fused dataset.ResultsThe method was evaluated successfully using titanium applicators in three patient cases and using a plastic applicator in a tissue-equivalent gel phantom.ConclusionsThe dual-echo technique provides a simple and efficient method for improving the visualisation of brachytherapy applicators in cervical cancer MRI images without the need for marker tubes.

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