The value of turbo spin-echo diffusion-weighted imaging apparent diffusion coefficient in the diagnosis of temporal bone cholesteatoma

2019 ◽  
Vol 74 (12) ◽  
pp. 977.e1-977.e7
Author(s):  
X. Fan ◽  
Z. Liu ◽  
C. Ding ◽  
Z. Chang ◽  
Q. Ma
2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Qiang Lei ◽  
Qi Wan ◽  
Lishan Liu ◽  
Jianfeng Hu ◽  
Wei Zuo ◽  
...  

Objective. This study is aimed at comparing the image quality and diagnostic performance of mean apparent diffusion coefficient (ADC) and lesion-to-spinal cord signal intensity ratio (LSR) derived from turbo spin-echo diffusion-weighted imaging (TSE-DWI) and echo-planar imaging- (EPI-) DWI in patients with a solitary pulmonary lesion (SPL). Methods. 33 patients with SPL underwent chest imaging using EPI-DWI and TSE-DWI with b = 600  s/mm2 in free breathing. A comparison of the distortion ratio (DR), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) was drawn between the two techniques using a Wilcoxon signed-rank test. The interprotocol reproducibility between quantitative parameters of EPI-DWI and TSE-DWI was evaluated using a Bland-Altman plot. ADCs and LSRs derived from EPI-DWI and TSE-DWI were calculated and compared between malignant and benign groups using the Mann–Whitney test. Results. TSE-DWI had similar SNR and CNR compared with EPI-DWI. DR was significantly lower on TSE-DWI than EPI-DWI. ADC and LSR showed slightly higher values with TSE-DWI, while the Bland-Altman analysis showed unacceptable limits of agreement between the two sequences. ADC and LSR of both DWI techniques differed significantly between lung cancer and benign lesions ( P < 0.05 ). The LSR(EPI-DWI) showed the highest area under the curve ( AUC = 0.818 ), followed by ADC(EPI-DWI) ( AUC = 0.789 ), ADC(TSE-DWI) ( AUC = 0.781 ), and LSR(TSE-DWI) ( AUC = 0.748 ), respectively. Among these parameters, the difference in diagnostic accuracy was not statistically significant. Conclusions. TSE-DWI provides significantly improved image quality in patients with SPL as compared with EPI-DWI. However, there was no difference in diagnostic efficacy between these two techniques, according to ADC and LSR.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jan Novak ◽  
Niloufar Zarinabad ◽  
Heather Rose ◽  
Theodoros Arvanitis ◽  
Lesley MacPherson ◽  
...  

AbstractTo determine if apparent diffusion coefficients (ADC) can discriminate between posterior fossa brain tumours on a multicentre basis. A total of 124 paediatric patients with posterior fossa tumours (including 55 Medulloblastomas, 36 Pilocytic Astrocytomas and 26 Ependymomas) were scanned using diffusion weighted imaging across 12 different hospitals using a total of 18 different scanners. Apparent diffusion coefficient maps were produced and histogram data was extracted from tumour regions of interest. Total histograms and histogram metrics (mean, variance, skew, kurtosis and 10th, 20th and 50th quantiles) were used as data input for classifiers with accuracy determined by tenfold cross validation. Mean ADC values from the tumour regions of interest differed between tumour types, (ANOVA P < 0.001). A cut off value for mean ADC between Ependymomas and Medulloblastomas was found to be of 0.984 × 10−3 mm2 s−1 with sensitivity 80.8% and specificity 80.0%. Overall classification for the ADC histogram metrics were 85% using Naïve Bayes and 84% for Random Forest classifiers. The most commonly occurring posterior fossa paediatric brain tumours can be classified using Apparent Diffusion Coefficient histogram values to a high accuracy on a multicentre basis.


2021 ◽  
Vol 10 (2) ◽  
pp. 205846012199473
Author(s):  
Takeshi Yoshizako ◽  
Rika Yoshida ◽  
Hiroya Asou ◽  
Megumi Nakamura ◽  
Hajime Kitagaki

Background Echo-planar imaging (EPI)-diffusion-weighted imaging (DWI) may take unclear image affected by susceptibility, geometric distortions and chemical shift artifacts. Purpose To compare the image quality and usefulness of EPI-DWI and turbo spin echo (TSE)-DWI in female patients who required imaging of the pelvis. Material and Methods All 57 patients were examined with a 3.0-T MR scanner. Both TSE- and EPI-DWI were performed with b values of 0 and 1000 s/mm2. We compared geometric distortion, the contrast ratio (CR) of the myometrium to the muscle and the apparent diffusion coefficient (ADC) values for the myometrium and lesion. Two radiologists scored the TSE- and EPI-DWI of each patient for qualitative evaluation. Results The mean percent distortion was significantly smaller with TSE- than EPI-DWI ( p = 0.00). The CR was significantly higher with TSE- than EPI-DWI ( p = 0.003). There was a significant difference in the ADC value for the uterus and lesions between the EPI- and TSE-DWI ( p < 0.05). Finally, the ADC values of cancer were significantly different from those for the uterus and benign with both the two sequences ( p < 0.05). The scores for ghosting artifacts were higher with TSE- than EPI-DWI ( p = 0.019). But there were no significant differences between TSE- and EPI-DWI with regard to image contrast and overall image quality. Conclusion TSE-DWI on the female pelvis by 3T MRI produces less distortion and higher CR than EPI-DWI, but there is no difference in contrast and image quality.


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