scholarly journals Improved Detectability of Brain Stem Ischemia by Combining Axial and Coronal Diffusion-Weighted Imaging

Stroke ◽  
2021 ◽  
Vol 52 (5) ◽  
pp. 1843-1846
Author(s):  
Paul Steffen ◽  
Lara-Sophie Beyer ◽  
Rosalie McDonough ◽  
Christian Thaler ◽  
Tobias Faizy ◽  
...  
Keyword(s):  
Brain Stem ◽  
Diffusion Weighted Imaging ◽  
Detection Rate ◽  
Predictive Values ◽  
Diffusion Weighted ◽  
Brain Stem Infarction ◽  
Certainty Level ◽  
Stem Lesions ◽  
Sensitivity Specificity ◽  
Brain Stem Ischemia

Background and Purpose: To evaluate the benefit of a coronal diffusion-weighted imaging (DWI) in addition to standard axial DWI for the detection of brain stem infarctions. Methods: A retrospective analysis of patients with symptoms consistent with acute and subacute brain stem infarction who received magnetic resonance imaging, including axial and coronal DWI. Diffusion restrictions were identified by 2 independent raters blinded for the final clinical diagnosis in 3 separate reading steps: axial DWI, coronal DWI, and combined axial and coronal DWI. Lesion location and certainty level were both documented for each reading step. In cases of reader disagreement, an additional consensus reading was performed. Results: Two hundred thirty-nine patients were included. Of these, 124 patients (51.9%) were clinically diagnosed with brain stem infarction. Sensitivity, specificity, positive, and negative predictive values were best for combined DWI assessment (90.3%, 99.1%, 99.1%, and 90.5%) compared with axial (85.5%, 94.9%, 94.6%, and 85.8%) and coronal DWI alone (87.9%, 96.5%, 96.5%, and 88.1%). Diffusion restriction on combined DWI was diagnosed in 112/124 patients compared with 106/124 on axial DWI and 109/124 on coronal DWI. Interobserver agreement for the detection of brain stem lesions was the highest in the combined rating step (Cohen κ coefficient=0.94). Conclusions: Coronal DWI sequences might improve the detection rate of brain stem infarction compared with standard axial DWI. The combined coronal and axial DWI provides the best detection rate while minimally increasing scan times.

scholarly journals The role of magnetic resonance cholangiopancreatography and diffusion-weighted imaging for the differential diagnosis of obstructive biliary disorders

2017 ◽  
Vol 21 (1) ◽  
Author(s):  
Zeynep Cetiner-Alpay ◽  
Fatma Kulali ◽  
Aslihan Semiz-Oysu ◽  
Yasar Bukte ◽  
Kamil Ozdil
Keyword(s):  
Magnetic Resonance ◽  
Sensitivity And Specificity ◽  
Gold Standard ◽  
Diffusion Weighted Imaging ◽  
Magnetic Resonance Cholangiopancreatography ◽  
Malignant Tumours ◽  
Diagnostic Efficacy ◽  
Diffusion Weighted ◽  
Sensitivity Specificity ◽  
And Diffusion

Background: Although endoscopic retrograde cholangiopancreatography (ERCP) is accepted as the gold standard, there is a place for magnetic resonance cholangiopancreatography (MRCP) and diffusion-weighted imaging (DWI) in the diagnosis of obstructive biliary disorders.Aim: To compare the findings of MRCP with ERCP in patients with obstructive biliary disorders and to investigate the diagnostic efficacy of MRCP combined with DWI.Study design: Retrospective, analytic, cross-sectional study.Methods: The MRCP images of 126 patients who underwent both MRCP and ERCP owing to biliary obstruction were reviewed. Nine patients were excluded because of incomplete diagnostic workup or a long period (>3 months) between MRCP and ERCP. Ninety-two patients underwent DWI, which was also evaluated. The sensitivity, specificity and accuracy of MRCP and DWI were analysed.Results: The sensitivity, specificity and accuracy of MRCP according to ERCP results as the gold standard was 97%, 71% and 93% for assessment of biliary dilatation; 100%, 94.7% and 97.5% for the diagnosis of choledocholithiasis; 93.7%, 100% and 99% for the identification of benign strictures; 100%, 100% and 100% for the diagnosis of malignant tumours; and 100%, 100% and 100% for the detection of complicated hydatid cysts; respectively. The sensitivity and specificity of DWI for the diagnosis of malignant tumour was 100%. In the detection of choledocholithiasis, the sensitivity and specificity of DWI was 70.8% and 100%.Conclusions: MRCP is an alternative, non-invasive, diagnostic modality, comparable with ERCP for the evaluation of pancreaticobiliary diseases. DWI can be helpful for diagnosis of choledocholithiasis and tumours.

scholarly journals Standard Diffusion-weighted MRI for the Diagnosis of Central Retinal Artery Occlusion

2020 ◽  
Author(s):  
L. A. Danyel ◽  
G. Bohner ◽  
F. Connolly ◽  
E. Siebert
Keyword(s):  
Optic Nerve ◽  
Central Retinal Artery Occlusion ◽  
Retinal Artery Occlusion ◽  
Artery Occlusion ◽  
Central Retinal Artery ◽  
Rater Reliability ◽  
Predictive Values ◽  
Diffusion Weighted ◽  
Retinal Artery ◽  
Sensitivity Specificity

Abstract Purpose To evaluate diffusion abnormalities of the retina and optic nerve in patients with central retinal artery occlusion (CRAO) using standard stroke diffusion-weighted magnetic resonance imaging (DWI). Methods In this case-control study, DWI scans of patients with nonarteritic CRAO were retrospectively assessed for acute ischemia of the retina and optic nerve. Two neuroradiologists, blinded for patient diagnosis, randomly evaluated DWI of CRAO patients and controls (a collective of stroke and transient ischemic attack [TIA] patients) for restrictions of the retina and optic nerve. We calculated statistical quality criteria and analyzed inter-rater reliability using unweighted Kappa statistics. Results 20 CRAO patients (60,6 ± 17 years) and 20 controls (60,7 ± 17 years) were included in the study. Sensitivity, specificity, positive and negative predictive values for retinal DWI restrictions were 75%/80%/79%/76% (reader 1) and 75%/100%/100%/80% (reader 2), respectively. Unweighted Kappa was κ = 0,70 (95% CI 0,48‑0,92), indicating “substantial” interrater reliability. In comparison, sensitivity, specificity, PPV and NPV (positive and negative predictive values) for restrictions of the optic nerve in CRAO were 55%/70%/65%/61% (reader 1) and 25%/100%/100%/57% (reader 2). Inter-rater reliability was “fair” with unweighted Kappa κ = 0,32 (95% CI 0,09‑0,56). Conclusions Retinal diffusion restrictions were present in a majority of CRAO patients and detectable with reasonable sensitivity, high specificity and substantial inter-rater reliability. Further studies are necessary to study time dependency of retinal diffusion restrictions, improve image quality and investigate the reliability of retinal DWI to discern CRAO from other causes of acute loss of vision.

scholarly journals Diffusion-Weighted Imaging with Two Differentb-Values in Detection of Solid Focal Liver Lesions

2016 ◽  
Vol 2016 ◽  
pp. 1-9
Author(s):  
Da-wei Yang ◽  
Ke-yang Wang ◽  
Xun Yao ◽  
Hui-yi Ye ◽  
Tao Jiang ◽  
...  
Keyword(s):  
Liver Disease ◽  
Prospective Study ◽  
Diffusion Weighted Imaging ◽  
Detection Rate ◽  
Focal Liver Lesions ◽  
Liver Lesions ◽  
Diffusion Weighted ◽  
Subgroup Analyses ◽  
To Receive ◽  
Mr Sequences

One hundred and eighty-two consecutive patients with suspected liver disease were recruited to receive diffusion-weighted imaging (DWI) with two differentb-values, in comparison with T2-weighted imaging (T2WI). The detection rate of three MR sequences in solid focal liver lesions (FLLs) and subgroup analyses were performed. Our prospective study found that DWI600 was equivalent to DWI100 and T2WI for the detection of solid FLLs overall but was significantly more accurate in the detection of malignant solid FLLs and lesions larger than 10 mm.

Anatomy of brain-stem white-matter tracts shown by diffusion-weighted imaging

2001 ◽  
Vol 43 (11) ◽  
pp. 953-960 ◽  
Author(s):  
C. Fitzek ◽  
M. Weissmann ◽  
H. Speckter ◽  
S. Fitzek ◽  
H. C. Hopf ◽  
...  
Keyword(s):  
White Matter ◽  
Brain Stem ◽  
Diffusion Weighted Imaging ◽  
White Matter Tracts ◽  
Diffusion Weighted

Diffusion-Weighted Magnetic Resonance Imaging of Cholesteatoma Using PROPELLER at 1.5T: A Single-Centre Retrospective Study

2017 ◽  
Vol 68 (2) ◽  
pp. 116-121 ◽  
Author(s):  
Sharon E. Clarke ◽  
Dipan Mistry ◽  
Talal AlThubaiti ◽  
M. Naeem Khan ◽  
David Morris ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Retrospective Study ◽  
Magnetic Resonance ◽  
Predictive Value ◽  
Resonance Imaging ◽  
Predictive Values ◽  
Second Look ◽  
Diffusion Weighted ◽  
Magnetic Resonance Imaging Mri ◽  
Sensitivity Specificity

Purpose The purpose of this study was to evaluate the sensitivity, specificity, and positive and negative predictive values of the diffusion-weighted periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) technique in the detection of cholesteatoma at our institution with surgical confirmation in all cases. Methods A retrospective review of 21 consecutive patients who underwent diffusion-weighted PROPELLER magnetic resonance imaging (MRI) on a 1.5T MRI scanner prior to primary or revision/second-look surgery for suspected cholesteatoma from 2009-2012 was performed. Results Diffusion-weighted PROPELLER had a sensitivity of 75%, specificity of 60%, positive predictive value of 86%, and negative predictive value of 43%. In the 15 patients for whom the presence or absence of cholesteatoma was correctly predicted, there were 2 cases where the reported locations of diffusion restriction did not correspond to the location of the cholesteatoma observed at surgery. Conclusion On the basis of our retrospective study, we conclude that diffusion-weighted PROPELLER MRI is not sufficiently accurate to replace second look surgery at our institution.

Role of Various DW MRI and DCE MRI Parameters as Predictors of Malignancy in Solid Pulmonary Lesions

2020 ◽  
pp. 084653712091489
Author(s):  
Neeraj Kumar ◽  
Mini Sharma ◽  
Neeti Aggarwal ◽  
Sanjiv Sharma ◽  
Malay Sarkar ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Diffusion Weighted Imaging ◽  
Breath Hold ◽  
Data Set ◽  
Predictive Values ◽  
Pulmonary Lesions ◽  
Dce Mri ◽  
Dynamic Contrast Enhanced ◽  
Diffusion Weighted ◽  
Contrast Enhanced

Purpose: We aimed to evaluate various diffusion and dynamic contrast-enhanced magnetic resonance imaging (DCE MRI) parameters in differentiating malignant from benign pulmonary lesions. Methods: We enrolled 31 (22 males) patients who had solid pulmonary lesion(s) >2 cm in our cross sectional study. Of these, 23 (74.2%) were found to be malignant on histopathology. Dynamic contrast-enhanced MRI was performed using 36 dynamic measurements (volumetric interpolated breath-hold examination). Diffusion-weighted MRI (DW MRI) performed at b value of 800 s/mm2. We measured different diffusion and perfusion parameters, for example, diffusion-weighted imaging (DWI) SI, mean apparent diffusion coefficient (ADC), minimum ADC, lesion-to-spinal cord ratio, DWI score, T2 score, Ktrans, Kep, and Ve. We stratified values of each parameter as high if it was >median of values observed in our data set and low if it was ≤median. Normally distributed data were compared by unpaired t test, whereas non-normal continuous data were compared by Kruskal Wallis-H test. We applied Wilson score method to calculate sensitivity, specificity, and predictive values of parameters that were statistically significant by type of lesion with reference to histopathological examination as gold standard. Results: Diffusion-weighted imaging SI, mean ADC, minimum ADC, DWI score and Ktrans values were found to be significantly different ( P value < .05) by type of lesion. Ktrans was found to have the highest diagnostic accuracy (74.2%) among these parameters. Conclusion: Ktrans and mean ADC had similar sensitivity of 65.2%. However, Ktrans had highest diagnostic accuracy among various DWI and DCE MRI parameters in predicting malignancy in solid pulmonary lesions. In our study, we found a cutoff value 0.251 min−1 for Ktrans as 100% specific.

scholarly journals Accuracy of Inchworm Sign on Diffusion-Weighted MRI in Differentiating Muscle-Invasive Bladder Cancer

2021 ◽  
pp. 1-10
Author(s):  
Huseyin Ozgur Kazan ◽  
Meftun Culpan ◽  
Nesrin Gunduz ◽  
Ferhat Keser ◽  
Ayberk Iplikci ◽  
...  
Keyword(s):  
Bladder Cancer ◽  
Invasive Bladder Cancer ◽  
Muscle Invasive Bladder Cancer ◽  
Predictive Values ◽  
Diffusion Weighted ◽  
Primary Bladder ◽  
Muscle Invasive ◽  
Sensitivity Specificity ◽  
Primary Bladder Cancer

BACKGROUND: Inchworm sign is a finding on diffusion-weighted magnetic resonance imaging (DWI-MRI) and is used to better stratify T-staging in muscle invasive (MIBC) and non-muscle-invasive bladder cancer (NMIBC). An uninterrupted low submucosal signal on DWI, defined as inchworm sign (IS), indicates NMIBC. OBJECTIVE: We aimed to define the diagnostic accuracy of IS in primary bladder cancer, as well as find agreement between the urologists and the radiologist. METHODS: Between December 2018 and December 2020, we retrospectively analyzed 95 primary bladder cancer patients who had undergone multiparametric-MRI before transurethral resection. Patients with former bladder cancer history, tumors smaller than 10 mm, and MRI without proper protocol, as well as patients who did not attend follow-up, were excluded. In total, 71 patients’ images were evaluated by a genitourinary specialist radiologist and two urologists. Sensitivity, specificity, positive and negative predictive values of IS and VI-RADS in differentiating MIBC and NMIBC, and interreader agreement between the radiologist and urologists were analyzed. RESULTS: During follow-up, 38 patients (53.5%) were IS-positive, while 33 patients (46.5%) were negative. Among the 33 patients with negative IS, 14 patients (42.4%) had MIBC. Meanwhile, two out of the 38 IS-positive patients (5.3%) had MIBC (p = 0.00). Sensitivity, specificity, and positive and negative predictive values of IS in predicting MIBC were 87.5%, 63.6%, 41.2%and 94.6%, respectively. The interobserver agreement between the urologists and radiologist was almost perfect ( K  = 0.802 and K  = 0.745) CONCLUSION: The absence of IS on DWI is useful in differentiating MIBC from NMIBC. It is a simple finding that can be interpreted by urologists.

scholarly journals A Comparative Analysis of Diffusion-weighted Imaging and Ultrasound in Thyroid Nodules

2019 ◽  
Author(s):  
Weidan Kong ◽  
Xiuhui Yue ◽  
Jiliang Ren ◽  
xiaofeng tao
Keyword(s):  
Signal Intensity ◽  
Diffusion Weighted Imaging ◽  
Thyroid Nodules ◽  
Area Under The Curve ◽  
High Sensitivity ◽  
High Specificity ◽  
Adc Value ◽  
Diffusion Weighted ◽  
Significant Difference ◽  
Sensitivity Specificity

Abstract Background: Diffusion-weighted imaging (DWI) and ultrasound are commonly used methods to examine thyroid nodules, but their comparative value is rarely studied. We evaluated the utility of DWI and ultrasound in differentiating benign and malignant thyroid nodules. Methods: A total of 100 patients with 137 nodules who underwent both DWI and ultrasound before operation were enrolled. The T1 and T2 signal intensity ratio (SIR) of each thyroid nodule was calculated by measuring the mean signal intensity divided by that of paraspinal muscle. The apparent diffusion coefficient (ADC) value and the SIR of benign and malignant thyroid nodules were analyzed by two-sample independent t tests. The sensitivity, specificity, and accuracy of DWI and ultrasound were compared with chi-square tests. Results: There was no significant difference in the SIR between benign and malignant thyroid nodules. The ADC value was significantly different. At the threshold value was 1.12 × 10 -3 mm 2 /s, the maximum area under the curve was 0.944. The sensitivity, specificity, and accuracy were 84.9%, 92.2%, and 87.6% respectively. The corresponding values of ultrasound diagnosis were 90.1%, 80.4%, and 86.9%. Conclusions: Ultrasound has high sensitivity in differentiating benign and malignant thyroid nodules, and the ADC value has high specificity, but there is no statistical difference in sensitivity or specificity between the two modalities. DWI and ultrasound each have their own advantages in differentiating benign and malignant thyroid nodules. Keywords Thyroid nodules, Ultrasound, Diffusion-weighted imaging

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