Changes in sensory-related brain networks of patients with moyamoya disease with limb paresthesia: A resting-state fMRI-based functional connectivity analysis.

This study's aim was to investigate functional brain connectivity changes among patients with moyamoya disease (MMD) with limb paresthesia, using functional connectivity analysis based on resting-state functional magnetic resonance imaging (rs-fMRI). A total of 181 patients with MMD were enrolled, including 57 with left limb paresthesia (MLP group), 61 with right limb paresthesia (MRP group), and 63 without paresthesia (MWP group). Encephaloduroarteriosynangiosis (EDAS) was performed in 20 of the 57 patients with left limb paresthesia and 15 of the 61 patients with right limb paresthesia. Twenty-nine age- and sex-matched healthy controls (HC group) were recruited during the same period. All participants underwent rs-fMRI examination, and the patients treated with EDAS were re-examined 3-4 months after the surgery. After data preprocessing, we selected Brodmann area 3 on each side of the brain as the seed region to construct a functional connectivity network of the whole brain, and then we analyzed the differences in functional connectivity between the HC group, MWP group, MLP group, and MRP group. The functional connectivity of Brodmann area 3 (on either side) with the ipsilateral frontal (superior frontal gyrus, middle frontal gyrus, and inferior frontal gyrus) and parietal (supramarginal gyrus, angular gyrus, and superior parietal lobule) cortices was increased among patients with MMD. The functional connectivity enhancement in these brain regions was broader and greater in patients with contralateral limb paresthesia than in patients without paresthesia, and the regions with functional connectivity changes were roughly distributed symmetrically among the MLP group and the MRP group. There were no changes 3-4 months after EDAS in the increased functional connectivity between the frontal and parietal cortices and Brodmann area 3. Limb paresthesia in patients with MMD may be driven by abnormal functional connectivity in the frontal and parietal cortices. Functional changes in associated brain regions may be a target for evaluating the severity of MMD and its response to treatment.

White matter structural and network topological changes in moyamoya disease with limb paresthesia: A study based on diffusion kurtosis imaging.

Purpose: To investigate the structural and network topological changes in the white matter (WM) in MMD patients with limb paresthesia by performing diffusion kurtosis imaging (DKI). Materials and methods: A total of 151 MMD patients, including 46 with left-limb paresthesia (MLP), 52 with right-limb paresthesia (MRP), and 53 without paresthesia (MWP), and 28 healthy controls (HCs) underwent whole-brain DKI, while the surgical patients were reexamined 3-4 months after revascularization. The data were preprocessed to calculate the fractional anisotropy (FA) and mean kurtosis (MK) values. Voxel-wise statistics for FA and MK images were obtained by using tract-based spatial statistics (TBSS). Next, the whole-brain network was constructed, and global and local network parameters were analyzed using graph theory. All parameters were compared among the HC, MWP, MLP, and MRP groups, and changes in the MMD patients before and after revascularization were also compared. Results: The TBSS analysis revealed significant reductions in FA and MK in extensive WM regions in the three patient groups. In comparison with the MWP group, the MLP group showed reductions in FA and MK in both right and left WM, mainly in the right WM, while the MRP group mainly showed a reduction in FA in the left WM region and demonstrated no significant change in MK. The graph theoretical analysis showed decreased global network efficiency, increased characteristic path length, and increased sigma in the MWP, MRP, and MLP groups in comparison with the HC group. Among local network parameters, the nodal efficiency decreased in the bilateral MFG and IFGtriang, while the degree decreased in the MFG.L and bilateral IFGtriang. Patients with right-limb paresthesia showed the lowest nodal efficiency and degree in MFG.L and IFGtriang.L, while those with left-limb paresthesia showed the lowest nodal efficiency in MFG.R and IFGtriang.R and the lowest degree in IFGtriang.R. Conclusion: A DKI-based whole-brain structural and network analysis can be used to detect changes in WM damage and network topological changes in MMD patients with limb paresthesia. FA is more sensitive than MK in detecting WM injury, while MFG and IFGtriang are the key nodes related to the development of acroparesthesia.

Blood Oxygen Level-Dependent Response Changes in the Ipsilateral Primary Somatosensory Cortex and Thalamus of Patients With Moyamoya Disease During Median Nerve Electrical Stimulation.

OBJECTIVE: The objective of this study was to investigate the changes in the blood oxygen level-dependent (BOLD) response in the ipsilateral primary somatosensory cortex (SI) and thalamus of patients with moyamoya disease (MMD) during sensory stimulation. METHODS: Sixty-four MMD patients, and 15 healthy volunteers were enrolled. Thirty-three MMD patients exhibited paroxysmal numbness or hypoesthesia in the unilateral limbs. Fifteen patients with acroparesthesia underwent unilateral encephaloduroarteriosynangiosis (EDAS). All volunteers underwent BOLD functional magnetic resonance imaging (BOLD-fMRI) under median nerve electrical stimulation (MNES). Blood oxygen level-dependent fMRI data were processed to obtain time-signal intensity curves in the activation areas of the bilateral SI and thalamus. Processed dynamic susceptibility contrast-enhanced magnetic resonance imaging data were used to measure the time to peak of the BOLD response in the regions of interest, including the bilateral SI, thalamus, and cerebellum. Changes in the time-signal intensity curve-related hemodynamic parameters in the ipsilateral SI and thalamus were examined between healthy controls, nonacroparesthesia patients, and asymptomatic and symptomatic sides of unilateral acroparesthesia patients during MNES. Changes in these parameters in MMD patients before and after EDAS were examined. RESULTS: Compared with healthy volunteers, 3 groups of MMD patients exhibited an increased peak of the positive BOLD response in the ipsilateral thalamus during MNES (0.65 ± 0.24 vs 0.79 ± 0.35, 0.94 ± 0.57, and 0.89 ± 0.50; P = 0.0335). The positive response peak in the ipsilateral SI markedly increased in MMD patients with acroparesthesia during MNES on the asymptomatic side (0.56 ± 0.37 vs 0.38 ± 0.27, P = 0.0243). The time to peak negative response in the ipsilateral SI was prolonged during MNES on the symptomatic side after EDAS (12.14 ± 8.90 seconds vs 18.86 ± 9.20 seconds, P = 0.0201). CONCLUSIONS: During sensory stimulation treatment, BOLD response changes occurred in the ipsilateral SI and thalamus of MMD patients. These changes enabled the contralateral hemisphere of the brain to better deal with sensory stimuli.

Weakly supervised 3D deep learning for breast cancer classification and localization of the lesions in MR images.

BACKGROUND: The usefulness of 3D deep learning-based classification of breast cancer and malignancy localization from MRI has been reported. This work can potentially be very useful in the clinical domain and aid radiologists in breast cancer diagnosis. PURPOSE: To evaluate the efficacy of 3D deep convolutional neural network (CNN) for diagnosing breast cancer and localizing the lesions at dynamic contrast enhanced (DCE) MRI data in a weakly supervised manner. STUDY TYPE: Retrospective study. SUBJECTS: A total of 1537 female study cases (mean age 47.5 years ±11.8) were collected from March 2013 to December 2016. All the cases had labels of the pathology results as well as BI-RADS categories assessed by radiologists. FIELD STRENGTH/SEQUENCE: 1.5 T dynamic contrast-enhanced MRI. ASSESSMENT: Deep 3D densely connected networks were trained under image-level supervision to automatically classify the images and localize the lesions. The dataset was randomly divided into training (1073), validation (157), and testing (307) subsets. STATISTICAL TESTS: Accuracy, sensitivity, specificity, area under receiver operating characteristic curve (ROC), and the McNemar test for breast cancer classification. Dice similarity for breast cancer localization. RESULTS: The final algorithm performance for breast cancer diagnosis showed 83.7% (257 out of 307) accuracy (95% confidence interval [CI]: 79.1%, 87.4%), 90.8% (187 out of 206) sensitivity (95% CI: 80.6%, 94.1%), 69.3% (70 out of 101) specificity (95% CI: 59.7%, 77.5%), with the area under the curve ROC of 0.859. The weakly supervised cancer detection showed an overall Dice distance of 0.501 ± 0.274. DATA CONCLUSION: 3D CNNs demonstrated high accuracy for diagnosing breast cancer. The weakly supervised learning method showed promise for localizing lesions in volumetric radiology images with only image-level labels. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2019;50:1144-1151.

Use of Breast Magnetic Resonance Imaging and Ultrasonography for Identifying Nonpalpable Axillae Metastases in Newly Diagnosed Breast Cancer Patients.

BACKGROUND: The metastasis of axillary lymph node (ALNs) is a critical step in the initial cancer staging of newly diagnosed breast cancer (BC) patients. Various imaging modalities can enhance the sensitivity of clinical examination in assessing the ALN status. PATIENTS AND METHODS: We enrolled 135 patients with BC, confirmed via histopathology, including 4 bilateral BC cases. A total of 139 ipsilateral ALNs adjacent to the breast lesion were examined via physical examination, ultrasonography (US), and magnetic resonance imaging (MRI); of these, 100 were nonpalpable ALNs, as determined by experienced breast surgeons and physicians. The relative size parameters on MRI and US images were recorded. Receiver operating characteristic (ROC) analyses were conducted, and the area under the ROC curve (AUC) was compared. RESULTS: Of 139 ALNs, 67 (48%) were malignant and 72 (52%) were benign on pathological examination. In all of the ALNs, the US short diameter appeared to be the most discriminative quantitative measurement for detecting positive findings (AUC, 0.854). In nonpalpable ALNs as well, the US short diameter exhibited the greatest discriminability (AUC, 0.746). However, the 2-dimensional and 3-dimensional parameters on MRI did not exhibit any significant differences between the enrolled and nonpalpable ALNs (P > .05). CONCLUSION: The shortest diameter on US exhibited better discriminative ability than MRI for predicting positive ALNs in nonpalpable axillae. Moreover, the 2-dimensional and 3-dimensional parameters on MRI did not differ in terms of discriminability.

Predicting Neoadjuvant Chemotherapy in Nonconcentric Shrinkage Pattern of Breast Cancer Using 1H-Magnetic Resonance Spectroscopic Imaging.

OBJECTIVE: The aim of this study was to explore the response to neoadjuvant chemotherapy (NAC) in nonconcentric shrinkage pattern of breast cancer (BC) patients using H-magnetic resonance spectroscopy. METHODS: Twenty-five BC patients were the study cohort. All patients received AT-based regimen as first-line treatment. Tumor response to chemotherapy was evaluated after the second and fourth cycles using magnetic resonance imaging and magnetic resonance spectroscopy. Final histopathology following surgery after 4 to 8 cycles of NAC served as a reference. Changes in total choline integral* (tCho) and tumor size in response versus nonresponse groups were compared using the 2-way Mann-Whitney nonparametric test. Receiver operating characteristic (ROC) analyses were undertaken, and the area under the ROC curve compared among them. RESULTS: H-magnetic resonance spectroscopy revealed a negative tCho integral* in 6 cases at the first follow-up and 14 cases at the second follow-up. Based on pathology (Miller-Payne system), there were 16 cases of response, and 9 cases of nonresponse. The tCho integral* was significantly different between the response and nonresponse groups at the second follow-up (P = 0.027). The tumor size changes were not significantly different in the response and nonresponse groups at the second follow-up study (P > 0.05). The comparison of ROC curves among the change in tCho integral* and tumor size at baseline and both follow-ups revealed the maximum area under the ROC curve of the change in tCho integral* to be 0.747 at the second follow-up, sensitivity to be 93.75%, and positive predictive value to be 78.9%. CONCLUSIONS: In nonconcentric shrinkage pattern after NAC of BC, when tumor size is difficult to reflect the response, tCho integral* reduction may be a predictive marker.

Cortical thickness changes in adult moyamoya disease assessed by structural magnetic resonance imaging.

PURPOSE: To characterize the changes in cortical thickness of adult patients with moyamoya disease (MMD). METHODS: 60 patients with MMD and 60 age and sex-matched healthy volunteers were recruited. Structural images were acquired by MRI. Freesurfer was used to measure cortical thickness in patients and controls, and this was compared with MRA scores and cerebrovascular accident (CVA) scores. RESULTS: Compared with controls, the average cortical thickness of both cerebral hemispheres was lower in patients than in controls and symmetrical differences were seen in the regional cortex: bilateral precentral gyri were thinner, bilateral postcentral gyri and posterior cingulate gyri were thicker, and thinning and thickening were both found in the insula. CVA scores were negatively correlated with the average cortical thicknesses. CONCLUSIONS: Cortical thickness can be used as a biological indicator to assess the severity of MMD.

BOLD-fMRI with median nerve electrical stimulation predict hemodynamic improvement after revascularization in patients with moyamoya disease.

PURPOSE: To assess the severity of cerebral hemodynamic impairment and hemodynamic improvements, after revascularization in moyamoya disease (MMD) by means of blood-oxygen-level dependent functional magnetic resonance imaging (BOLD-fMRI). MATERIALS AND METHODS: BOLD-fMRI with median nerve electrical stimulation based on echo planar imaging was performed in 73 volunteers with MMD and 15 healthy volunteers using a 3.0 Tesla MRI scanner. Twenty-four MMD patients were reexamined after encephaloduroarteriosynangiosis. Time-signal intensity curves of the activated area of the contralateral primary somatosensory cortex were computed. Negative response time (Tnr) and peak (Pnr), positive response time (Tpr) and peak (Ppr), and time to negative peak (TTPn) and positive peak (TTPp) were measured. RESULTS: Compared with nonparesthesia group and the asymptomatic side of paresthesia group, the patients with paresthesia showed extended Tnr (22.04 ± 3.34 s versus 9.57 ± 2.27 s and 12.67 ± 2.69 s, P = 0.0096), decreased Pnr (-0.47 ± 0.06 versus -0.30 ± 0.09 and -0.33 ± 0.09, P = 0.010), delayed TTPn (9.04 ± 1.39 s versus 3.66 ± 0.79 s and 4.88 ± 1.10 s, P = 0.0064), shortened Tpr (22.75 ± 2.30 s versus 36.85 ± 2.68 s and 33 ± 2.49 s, P = 0.0010), and decreased Ppr (0.62 ± 0.08 versus 0.99 ± 0.15 and 0.97 ± 0.11, P = 0.0149) when subjected to median nerve electrical stimulation in the symptomatic side. After surgery, the patients with paresthesia showed shorter Tnr (1.53 ± 1.66 s versus 17.88 ± 22.61 s, P = 0.0002), increased Pnr (-0.14 ± 0.17 versus -0.44 ± 0.53, P = 0.0178), advanced TTPn (1.29 ± 1.21 s versus 7.29 ± 8.21 s, P = 0.0005), extended Tpr (36.94 ± 6.41 s versus 25.18 ± 15.51 s, P = 0.0091), increased Ppr (1.21 ± 0.87 versus 0.77 ± 0.60, P = 0.0201), and advanced TTPp (11.18 ± 4.70 s versus 27.29 ± 20.00 s, P = 0.0046). CONCLUSION: Bold-fMRI is useful to assess disease severity and surgical efficacy in MMD. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2017;46:1159-1166.

Clinical assessment of cerebral hemodynamics in Moyamoya disease via multiple inversion time arterial spin labeling and dynamic susceptibility contrast-magnetic resonance imaging: A comparative study.

BACKGROUND AND PURPOSE: For Moyamoya disease (MMD) patients, accurate hemodynamic assessment is critical for treatment selection and efficacy assessment. This study aims to investigate the clinical value of mTI-ASL in assessing the cerebral hemodynamics of MMD patients before and after revascularization, relative to DSC-MRI. MATERIALS AND METHODS: Forty-one MMD patients underwent mTI-ASL and DSC-MRI during blood perfusion. Quantitative parameters for the bilateral supply vessels of middle and anterior cerebral arteries, including DSC-TTP, DSC-CBF, ASL-BAT, and ASL-CBF were measured. The correlations between DSC-ΔTTP (TTPhemisphere - TTPbrainstem) and ASL-ΔBAT (BAThemisphere - BATbrainstem) and between DSC-CBF and ASL-CBF were determined. The consistency between the two techniques in assessing the cerebral ischemic state before and after revascularization was analyzed. RESULTS: DSC-ΔTTP and ASL-ΔBAT (r=0.36, P<0.001) and DSC-CBF and ASL-CBF (r=0.32, P<0.001) exhibited significant correlation on 824 regions of interest (ROIs) and similar numbers of ischemic areas on 902 ROIs (κ=0.82, P<0.001). The ischemic scores were 3.17±3.02 and 2.98±2.81 by DSC-MRI and ASL-MRI, respectively (ICC=0.92). For 15 surgically treated patients, the scores for blood perfusion improvement on the operated side were 3.13±1.68 and 3.27±1.33 with DSC-TTP and ASL-BAT, respectively (ICC=0.94). CONCLUSION: Compared to DSC-MRI, mTI-ASL can assess the cerebral hemodynamics in MMD and evaluate ischemic state before revascularization and ischemia reduction after revascularization effectively. And mTI-ASL is more advantageous because it does not require contrast agents.

Changes in Hemodynamic Response Patterns in Motor Cortices Measured by Task-Based Functional Magnetic Resonance Imaging in Patients With Moyamoya Disease.

OBJECTIVE: We aimed to study the value of blood oxygen level-dependent functional magnetic resonance imaging (BOLD-fMRI) in assessing cerebral hemodynamic changes for moyamoya disease (MMD). METHODS: We recruited 15 healthy volunteers, 15 patients with MMD without dyskinesia, and 30 patients with MMD who experienced paroxysmal limb dyskinesia. The BOLD-fMRI scans were obtained during grasping motions of the left or right hand. Hemodynamic response curves in the primary motor cortices were generated. Six response parameters including negative response time (Tnr), maximum signal intensity of negative response, time to peak, maximum peak arrival time, maximum signal intensity of positive response, and positive response time were measured. RESULTS: The hemodynamic response curve in the primary motor cortices of MMD patients showed extended Tnr, prolonged positive response time, and delayed time to peak than those of the controls. The response curve showed longer Tnr and maximum peak arrival time in the primary motor cortices on the affected side of the dyskinesia group. CONCLUSIONS: Blood oxygen level-dependent fMRI is an effective technique to assess hemodynamic changes in patients with MMD.

Feasibility of quantitative parameters of dynamically enhanced patterns of spiral computed tomography scanning integrated into tumour progression before targeted treatment of non-small cell lung cancer.

INTRODUCTION: The relationship between quantitative parameters of contrast-enhanced computed tomography (CT) and non-small cell lung cancer (NSCLC) progression remains controversial. We aimed to explore the usefulness of contrast-enhanced spiral CT scanning for confirming the time of tumour progression before targeted treatment of NSCLC. METHODS: Contrast-enhanced spiral CT scanning was performed on 33 NSCLC patients with a biopsy-proven diagnosis of NSCLC. All the patients were divided into three groups according to times of tumour progression (<6 weeks, 6-20 weeks, and >20 weeks). The perfusion CT data were used to calculate quantitative parameters, including enhanced peak values, peak time of tumour enhancement, ratio of tumour mass and enhanced aorta peak value and perfusion value of blood flow. Variance analysis was used for statistical analysis among the three groups using SAS 9.13 statistical software. RESULTS: Tumour perfusion values among the three group with different stage of TTP were significantly different from each other with P = 0.0129 (<6 weeks, perfusion value = 0.35 ± 0.15 mL/(min × mL); 6-20 weeks, perfusion value = 0.41 ± 0.086 mL/(min × mL); > 20 weeks, perfusion value = 0.47 ± 0.087 mL/(min × mL)). However, no significant differences were found in other parameters (enhanced peak values, peak time of tumour enhancement, ratios of tumour mass, and enhanced aorta peak value) among three groups (P > 0.05). CONCLUSION: The NSCLC patients with high perfusion value before targeted therapy are more sensitive to targeted therapy, and further experiments with larger sample size are needed.

[Comparison of response evaluation methods of neoadjuvant chemotherapy in breast cancer patients].

OBJECTIVE: To compare the efficiency of response evaluation by clinical examination, ultrasonograghy and mammography in neoadjuvant chemotherapy (NAC) for breast cancer. METHODS: A retrospective cohort study was conducted to analyze the data of 141 patients treated with neoadjuvant chemotherapy. Response evaluation was performed by clinical palpation, ultrasound and mammography. RESULTS: Only 12 (8.5%) among the 141 patients presented with a stage I tumor. The tumor size determined by palpation was often larger than that by ultrasound before therapy (P < 0.01). Among patients with suspicions axillary nodes checked by ultrasound, 88.3% (53/60) of them had positive nodes by pathology before NAC, and 34.5% (10/29) of patients with negative nodes determined by ultrasound had positive nodes by pathology. In all the 141 patients, 21(14.9%) showed pathological complete remission in both the primary tumor and lymph node. For response evaluation, the false complete remission rate judged by clinical examination was 46.8% (22/47), and the false tumor residual rate by ultrasound was 84.0% (21/25). In 53.5% (23/43) of patients the response could not be assessed by mammography due to that the tumors were undistinguishable in size. The range of microcalcification was not reduced in 5 patients with a partial response of the tumor. 25 patients experienced needle puncture during therapy. Among them, in the 9 pathologically negative patients, only 3 achieved pCR, and the other 16 positive patients didn't achieve pCR. CONCLUSION: Using the puncture or sentinel lymph node biopsy, clinicians should pay enough emphasis on the pathological determination of the node status before chemotherapy. Clinicians will make a quite of false judgment of the tumor by clinical examination, ultrasound or mammography. They may use needle puncture during therapy to evaluate the response of neoadjuvant chemotherapy, and the result should be analyzed synthetically.