Diffusion Weighted Magnetic Research Articles

Intravoxel Incoherent Motion Diffusion-weighted Magnetic Resonance Imaging combined with Texture Analysis in Predicting the Histological Grades of Rectal Adenocarcinoma.

To evaluate the predictive value of 3.0T MRI Intravoxel Incoherent motion diffusion-weighted magnetic resonance imaging (IVIM-DWI) combined with texture analysis (TA) in the histological grade of rectal adenocarcinoma. Seventy-one patients with rectal adenocarcinoma confirmed by pathology after surgical resection were collected retrospectively. According to pathology, they were divided into a poorly differentiated group (n=23) and a moderately differentiated group (n=48). The IVIM-DWI parameters and TA characteristics of the two groups were compared, and a prediction model was constructed by multivariate logistic regression analysis. ROC curves were plotted for each individual and combined parameter. There were statistically significant differences in D and D* values between the two groups (P < 0.05). The three texture parameters SmallAreaEmphasis, Median, and Maximum had statistically significant differences between groups (P = 0.01, 0.004, 0.009, respectively). The logistic regression prediction model showed that D*, the median, and the maximum value were significant independent predictors, and the AUC of the regression prediction model was 0.860, which was significantly higher than other single parameters. 3.0T MRI IVIM-DWI parameters combined with TA can provide valuable information for predicting the histological grades of rectal adenocarcinoma one week before the operation.

Shear Wave Ultrasound Elastography and Diffusion-Weighted Magnetic Resonance Imaging Findings of Pleural-Based Masses with Histopathologic Correlation

Objective: The study aims to evaluate the usefulness of non-invasive diagnostic methods, shear wave elastography (SWE), and diffusion-weighted magnetic resonance imaging (DWI) to differentiate benign and malignant lesions in the thoracic pleural based masses by comparing them with histopathological findings.Materials and Methods: Sixty-three patients having a pleural-based peripheral mass on CT, admitted to the interventional radiology department for transthoracic biopsy, were included in the study. All patients underwent DWI, and ADC values of the groups were measured. Transthoracic biopsy was performed with the guidance of US from the area where the highest shear wave velocity (SWV) value was calculated. ADC and SWV values of histopathologically proven benign and malignant lesions were statistically compared.Results: Fifty-six patients were male, and seven were female. The mean age was 64.68±10.13 years (41-85 years). Fourty-four patients were malignant, and 19 were benign. The maximum SWV was found to be 4.13±0.59 m/s in malignant cases and 3.55±0.71 m/s in benign cases, and the difference was significant (p = 0.001). Mean ADC value was measured as 1.04±0.30 x 10-3 mm2/s in malignant cases and 1.32±0.33 x 10-3 mm2/s in benign cases on DWI and the difference was significant (p = 0.002). In malignant cases, the minimum ADC was 0.73±0.29 x 10-3 mm2/s, and 0.99±0.44 x 10-3 mm2/s in benign cases, the difference was significant (p = 0.024). ROC analysis revealed a cut-off value of ≥4.08 m/s for SWVmax, ≤1.01x10-3 mm2/s for mean ADC, and ≤0.8x10-3 mm2/s for minimum ADC showed a significant performance in distinguishing malignant and benign lesions. Conclusions: Transthoracic US elastography and DWI are useful in differentiating malignant and benign lesions in appropriate cases. Both SWE and DWI are useful in routine use because they are non-invasive and do not contain radiation. In particular, SWE is suitable for biopsy guidance and may prevent the possibility of insufficient material.

MP51-09 DIFFUSION-WEIGHTED MAGNETIC RESONANCE IMAGING AND MR SPECTROSCOPY TO DETECT CANCER DISTRIBUTION IN PROSTATE.

You have accessJournal of UrologyProstate Cancer: Localized V1 Apr 2014MP51-09 DIFFUSION-WEIGHTED MAGNETIC RESONANCE IMAGING AND MR SPECTROSCOPY TO DETECT CANCER DISTRIBUTION IN PROSTATE. Kosuke Kitamura, Satoru Muto, Shou-ichirou Sugiura, Akira Horiuchi, Masa-aki Koja, Akiko Nakajima, Masahiro Inoue, Yasuhiro Noma, Shino Tokiwa, Keisuke Saitou, Shuji Isotani, Hisamitsu Ide, Raizou Yamaguchi, and Shigeo Horie Kosuke KitamuraKosuke Kitamura More articles by this author , Satoru MutoSatoru Muto More articles by this author , Shou-ichirou SugiuraShou-ichirou Sugiura More articles by this author , Akira HoriuchiAkira Horiuchi More articles by this author , Masa-aki KojaMasa-aki Koja More articles by this author , Akiko NakajimaAkiko Nakajima More articles by this author , Masahiro InoueMasahiro Inoue More articles by this author , Yasuhiro NomaYasuhiro Noma More articles by this author , Shino TokiwaShino Tokiwa More articles by this author , Keisuke SaitouKeisuke Saitou More articles by this author , Shuji IsotaniShuji Isotani More articles by this author , Hisamitsu IdeHisamitsu Ide More articles by this author , Raizou YamaguchiRaizou Yamaguchi More articles by this author , and Shigeo HorieShigeo Horie More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2014.02.1665AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail Introduction and Objectives The management of localized prostate cancer (PCa) is in rapid evolution. In CaPSURE, the proportion of patients with low-risk disease has increased, and conversely, high-risk diagnoses have decreased. To prevent overtreatment, new concept of active surveillance and focal therapy as opposed to traditional radical treatment have appeared in clinical practice. The most important thing is, however, to diagnose the precise distribution and characteristics of all cancer lesions including daughter small tumors. The purpose of this study is to evaluate the efficacy of diffusion-weighted MRI (DWI), MR Spectroscopy (1H-MRS) and prostate biopsy (PBx) for detecting the intraprostatic cancer distribution. Methods We included 54 consecutive patients with PCa in this retrospective study. All patients received DWI, 1H-MRS and PBx followed by radical prostatectomy. As a matter of convenience of comparing these imaging and histological outcome, a prostate was divided into 12 sections. Each of these regions was examined for the presence/absence of malignancy on the basis of DWI, 1H-MRS, and PBx, respectively. Then, these results were compared with the histopathological findings for the total prostatectomy specimens. We judge the sensitivity, positive predictive value (PPV) and negative predictive value (NPV) of DWI, 1H-MRS, and PBx by computing the area under the Receiver Operator Characteristic curve (AUC). Results We included 53 patients (median age, 63 years; range, 43-75 years). Median PSA value was 5.8 ng/ml (range; 2.1-26.3). We could detect cancer lesion in 242 of 636 evaluable lesions. Every parameters of DWI for the diagnosis of prostate cancer was higher compared with 1H-MRS, and PBx (sensitivity: DWI 93.2%, 1H-MRS 78.4%, PBx 87.9%; PPV: DWI 68.3%, 1H-MRS 68.1% PBx 67.7%; NPV: DWI 63.5%, 1H-MRS 45.1%, PBx 50.5%) (Figure). AUC analysis found that DWI also had an higher AUC of 0.57 compared with 1H-MRS (0.55) and PBx (0.55). Conclusions DWI is more efficient than 1H-MRS and PBx in the detection of intraprostatic cancer distribution. © 2014FiguresReferencesRelatedDetails Volume 191Issue 4SApril 2014Page: e600 Advertisement Copyright & Permissions© 2014MetricsAuthor Information Kosuke Kitamura More articles by this author Satoru Muto More articles by this author Shou-ichirou Sugiura More articles by this author Akira Horiuchi More articles by this author Masa-aki Koja More articles by this author Akiko Nakajima More articles by this author Masahiro Inoue More articles by this author Yasuhiro Noma More articles by this author Shino Tokiwa More articles by this author Keisuke Saitou More articles by this author Shuji Isotani More articles by this author Hisamitsu Ide More articles by this author Raizou Yamaguchi More articles by this author Shigeo Horie More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

RE: Diffusion-Weighted Imaging of Prostate Cancer: How Can We Use It Accurately?

To the editors, We read with great interest the article titled “DiffusionWeighted Magnetic Resonance Imaging for the Evaluation of Prostate Cancer: Optimal B Value at 3T” by Ji Hyun Koo et al. (1), published in the Korean Journal of Radiology (DOI: 10.3348/kjr.2013.14.1.61). This article will be a useful diffusion weighted imaging (DWI) guide for radiologists in assessing prostatic cancer. In the paper, the authors compared 4 different b values and suggested them for predicting prostate cancer; the optimal b value for 3T DWI was found to be 1000 s/mm. However, even with high b values, the overlap of the apparent diffusion coefficient (ADC) limits the accuracy of DWI in cancer detection, particularly in the transitional zone tissue, due to its lower ADC compared to the peripheral zone tissue (2). Therefore, we aimed to mention that, with

Acute Infarction at the Opto-Chiasmal Junction Detected by Diffusion Weighted Magnetic Resonance Imaging

ABSTRACTA localized infarction at the junction of the optic nerve and chiasm (opto-chiasmal junction) is rare and difficult to detect by conventional neuro-imaging techniques. The purpose of this report is to show the diagnostic potential of diffusion-weighted magnetic resonance imaging for lesions at this location. A 62-year-old woman complained of sudden visual loss in her left eye. Visual field testing strongly suggested that the left opto-chiasmal junction was damaged. Diffusion weighted imaging demonstrated an area of restricted diffusion at the left opto-chiasmal junction, whereas the T2 weighted and fluid-attenuated inversion recovery sequences revealed no abnormality.

High‐resolution DTI of a localized volume using 3D single‐shot diffusion‐weighted STimulated echo‐planar imaging (3D ss‐DWSTEPI)

Diffusion tensor MRI (DTI) using conventional single-shot (SS) 2D diffusion-weighted (DW)-EPI is subject to severe susceptibility artifacts. Multishot DW imaging (DWI) techniques can reduce these distortions, but they generally suffer from artifacts caused by motion-induced phase errors. Parallel imaging can also reduce the distortions if the sensitivity profiles of the receiver coils allow a sufficiently high reduction factor for the desired field of view (FOV). A novel 3D DTI technique, termed 3D single-shot STimulated EPI (3D ss-STEPI), was developed to acquire high-resolution DW images of a localized region. The new technique completes k-space acquisition of a limited 3D volume after a single diffusion preparation. Because the DW magnetization is stored in the longitudinal direction until readout, it undergoes T(1) rather than T(2) decay. Inner volume imaging (IVI) is used to limit the imaging volume. This reduces the time required for EPI readout of each complete k(x)-k(y) plane, and hence reduces T(2)(*) decay during the readout and T(1) decay between the readout of each k(z). 3D ss-STEPI images appear to be free of severe susceptibility and motion artifacts. 3D ss-STEPI allows high-resolution DTI of limited volumes of interest, such as localized brain regions, cervical spinal cord, optic nerve, and other extracranial organs.

Online motion correction for diffusion-weighted imaging using navigator echoes: Application to RARE imaging without sensitivity loss.

This article describes the first application of true online motion correction to diffusion-weighted RARE imaging. Two orthogonal navigator echoes were acquired and zeroth and first-order phase corrections applied in less than 8 ms between a diffusion-weighted magnetization preparation and data acquisition using the RARE sequence. The zeroth-order phase correction was realized by pulsing the system's B(0)-coil: the first-order error corrected with appropriate magnetic field gradient pulses. Online correction ensured that no irreversible signal loss could occur in the imaging experiment. Diffusion-weighted images of the brain were obtained from healthy volunteers. EGG-triggered acquisition was applied at 400 ms after the R-wave. Data were acquired on a matrix of 256 x 256 with a RARE factor of 16 and a b-value of 804 smm(-2). The images obtained with online motion correction showed a remarkably high image quality, while those acquired without motion correction were severely degraded by artifacts.

Abstracts of Literature

Abstracts of Literature