Assessing the Early Response of Advanced Cervical Cancer to Neoadjuvant Chemotherapy Using Intravoxel Incoherent Motion Diffusion-weighted Magnetic Resonance Imaging: A Pilot Study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Diffusion-weighted imaging (DWI) with the intravoxel incoherent motion (IVIM) model has shown promising results for providing both diffusion and perfusion information in cervical cancer; however, its use to predict and monitor the efficacy of neoadjuvant chemotherapy (NACT) in cervical cancer is relatively rare. The study aimed to evaluate the use of DWI with IVIM and monoexponential models to predict and monitor the efficacy of NACT in cervical cancer.</p><p><b>METHODS</b>Forty-two patients with primary cervical cancer underwent magnetic resonance exams at 3 time points (pre-NACT, 3 weeks after the first NACT cycle, and 3 weeks after the second NACT cycle). The response to treatment was determined according to the response evaluation criteria in solid tumors 3 weeks after the second NACT treatment, and the subjects were classified as two groups: responders and nonresponders groups. The apparent diffusion coefficient (ADC), true diffusion coefficient (D), perfusion-related pseudo-diffusion coefficient (DFNx01), and perfusion fraction (f) values were determined. The differences in IVIM-derived variables and ADC between the different groups at the different time points were calculated using an independent samples t-test.</p><p><b>RESULTS</b>The D and ADC values were all significantly higher for the responders than for the nonresponders at all 3 time points, but no significant differences were observed in the DFNx01 and f values. An analysis of the receiver operating characteristic (ROC) curves indicated that a D value threshold <0.93 × 10-3 mm 2 /s and an ADC threshold <1.11 × 10-3 mm 2 /s could differentiate responders from nonresponders at pre-NACT time point, yielding area under the curve (AUC) of which were 0.771 and 0.806, respectively. The ROC indicated that the AUCs of D and ADC at the 3 weeks after the first NACT cycle and 3 weeks after the second NACT cycle were 0.823, 0.763, and 0.787, 0.794, respectively. The AUC values of D and ADC at these 3 time points were not significantly different (P = 0.641, 0.512, and 0.547, respectively).</p><p><b>CONCLUSIONS</b>D and ADC values may be useful for predicting and monitoring the efficacy of NACT in cervical cancer. An IVIM model may be equal to monoexponential model in predicting and monitoring the efficacy of NACT in cervical cancer.</p>

Tuberous sclerosis complex: Imaging characteristics in 11 cases and review of the literature / 华中科技大学学报（医学）（英德文版）

Tuberous sclerosis complex (TSC) is an uncommon multiorgan disorder that may present many and different manifestations on imaging. Radiology plays an important role in diagnosis and management, and can substantially improve the clinical outcome of TSC. Therefore, a comprehensive understanding of this disease is essential for the radiologist. The manifestations of TSC on computer tomography (CT) and magnetic resonance (MR) images were analyzed. Eleven patients with a clinical diagnosis of TSC were retrospectively reviewed. Central nervous system lesions included subependymal nodules (SENs) (11/11), subependymal giant cell astrocytomas (SEGAs) (2/11), cortical and subcortical tuber lesions (5/11), and white matter lesions (4/11). Of the 6 patients with abdominal scans, there were 6 cases of renal angiomyolipomas (AMLs), and one case of hepatic AMLs. Of the 4 patients undergoing chest CT, lung lymhangioleiomyomatosis (LAM) (2/4), and multiple small sclerotic bone lesions (2/4) were observed. Different modalities show different sensitivity to the lesion. Analysis of images should be integrated with patients' history in order to diagnose TSC.

Role of diffusion-weighted imaging in early ankylosing spondylitis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>With the advanced MRI techniques, pathologic features can be detected at an early stage and quantitatively evaluated, resulting in the advantages of early diagnosis and prompt treatment. This study aimed to determine the value of diffusion-weighted MR imaging (DWI) in detection of early ankylosing spondylitis (AS) and investigate the characteristic manifestations of AS on whole body DWI (WB-DWI).</p><p><b>METHODS</b>Twenty patients with the diagnosis of early AS, twenty patients with low back pain (LBP), and twenty-five healthy volunteers were included in this study. The subchondral bone apparent diffusion coefficients (ADC) among these groups in the bilateral ilia and sacrum along the sacroiliac joints were compared. An independent sample t-test was utilized to analyze ADC value differences among groups. P-values less than 0.05 denoted statistical significance. The mean ADC values of focal DWI lesions in AS patients were also measured. Whole body diffusion-weighted imaging was performed in fifteen additional AS patients, and analyzed with MIP and MPR techniques in comparison to conventional MR images in order to evaluate the ability to detect AS lesions with whole body DWI.</p><p><b>RESULTS</b>Mean ADC values in AS patients were (0.518 ± 0.122) × 10(-3) mm(2)/s in the ilium and (0.503 ± 0.168) × 10(-3) mm(2)/s in the sacrum. These were significantly greater than the values measured in the ilium and sacrum of LBP patients, (0.328 ± 0.053) × 10(-3) mm(2)/s in the ilium and (0.311 ± 0.081) × 10(-3) m(2)/s in the sacrum, and control group, (0.325 ± 0.015) × 10(-3) mm(2)/s in the ilium and (0.318 ± 0.011) × 10(-3) mm(2)/s in the sacrum respectively. No statistically significant differences were found between LBP group and control group. The mean ADC value of focal DWI lesions in early AS patients was (0. 899 ± 0.265) × 10(-3) mm(2)/s, which was significantly higher than that of adjacent normal-appearance areas ((0.454 ± 0.079) × 10(-3) mm(2)/s). WB-DWI detected abnormalities in the 15 additional AS patients both within the sacroiliac joints and at other sites, corresponding to the clinical symptoms of the patients. The mean ADC value of focal DWI lesions of this patient cohort was (1.286 ± 0.311) × 10(-3) mm(2)/s in the sacrum and (1.220 ± 0.299) × 10(-3) mm(2)/s in the ilium.</p><p><b>CONCLUSIONS</b>Subchondral marrow ADC values of subchondral marrows near the sacroiliac joints allow for the differentiation of patients with early AS from normal volunteers and LBP patients. Combined with post-processing techniques such as MIP and MPR, WB-DWI allows for the comprehensive assessment of AS patients, an evaluation potentially helpful in determining prognosis and following the therapeutic response.</p>

Dynamic gadoteridol-enhanced MR imaging in the end of growing long bone of piglets / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>It is of value to identify the non-invasive means that can accurately reflect the blood supply of epiphysis and is more sensitive in detection of early ischemia of epiphysis than the conventional gadoteridol (Gd)-enhanced SE T1WI. The aim of this study was to evaluate the blood supply of various anatomic regions at the end of normal growing long bone using dynamic Gd-enhanced MR imaging and compare the sensitivities between dynamic Gd-enhanced MR imaging and conventional Gd-enhanced SE T1WI in the detection of decreased blood perfusion of early epiphyseal ischemia.</p><p><b>METHODS</b>Twenty-seven two-week-old piglets were used in this study. For the study of the end of normal growing long bone, unilateral MR imaging of the distal femur and proximal tibia was performed on eleven piglets. The comparison was made among various anatomic regions (physeal and epiphyseal cartilage, metaphyseal spongiosa, the secondary ossification center and metaphysis) using MRI in terms of the enhancement ratio and speed. Their relationships with the histological findings, including RBC/mm(2) and vessel distribution, were evaluated. To examine ischemic femoral head, 16 piglets were divided into two groups, with the control group having 8 piglets (involving 16 normal hips) and an ischemic group having 8 piglets (involving 16 hips with hyperabduction). In the ischemic group, MR imaging was performed on the hips in the hyperabduction immobilized persistently for 30 minutes. After MRI, the piglets were allowed to ambulate freely for 1 day and the same MR scanning was then repeated in a neutral position. The difference in enhancement ratio and speed of the femoral head between the control and ischemic group were evaluated.</p><p><b>RESULTS</b>With regard to the end of normal growing long bone, the enhancement ratio of the metaphyseal spongiosa was greatest among all the anatomic regions (P < 0.001). The enhancement ratio of physeal cartilage was greater than that of epiphyseal cartilage (P < 0. 001), which was the lowest in all tissues (P < 0.001). The enhancement speed of the spongiosa was greater than that of physis but the difference was not significant (P > 0.05). The enhancement speed of physis was greater than that of epiphyseal cartilage (P < 0.05), which was the lowest among all the tissues (P < 0.05). The enhancement ratio and speed were found to be related to the histological findings, including RBC/mm(2) (R > 0.75) and distribution of vessels in the tissues. With ischemic femoral head, the enhancement ratios of physis, anterior part and posterior part of capital femoral epiphysis were significantly lower (P < 0.05) and enhanced more slowly (P < 0.05) than those of normal femoral head on dynamic Gd-enhanced MR imaging. On conventional Gd-enhanced SE T1WI, however, no apparent decrease in enhancement ratio and speed in ischemic hips was found (P < 0.05), when they were compared with those in the normal hips.</p><p><b>CONCLUSIONS</b>Dynamic gadoteridol-enhanced MR imaging can reveal the blood supply in various anatomic regions of the end of normal growing long bone. It is more sensitive than conventional Gd-enhanced SE T1WI in the detection of early epiphyseal ischemia.</p>

Evaluation of whole body MRI and diffusion-weighted MRI in detecting intranodal lesions in patients with lymphoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the whole body MRI and diffusion-weighted MRI in detecting intranodal lesions in patients with lymphoma.</p><p><b>METHODS</b>Whole body MRI and diffusion-weighted MRI (DWI) were performed in 23 patients with histologically proven lymphoma. A conventional coronal MRI scan from head to inguinal groove was done for whole body scanning. In the DWI, axial MRI scans were performed after segmentation based on SENSE technique, and all images were merged into whole body image reconstruction by software.</p><p><b>RESULTS</b>417 lymph nodes were detected by MRI in the 23 patients. The overall positive rate of whole body MRI and DWI was 79.1% and 89.7%, respectively. It was 70.9% versus 85.2% and 79.4% versus 90.1% for the lymph nodes of < 2 cm and 2-3 cm in diameter, with a significant difference between the two methods (P < 0.01). However, it was 94.7% versus 97.9% for the lymph nodes of > 3 cm in diameter, not significantly different between the two methods (P > 0.05). Both methods had similar sensitivity in detecting the lymph nodes in the neck, supraclavicular and infraclavicular fossae, mediastinum and axillary fossa. However, the positive rate of whole body MRI was 51.2%, 43.8% and 52.2%, significantly less sensitive than 83.7%, 71.9% and 87.0%, respectively, by DWI in detecting the lymph nodes in the retroperitoneal space, pelvic cavity and inguinal groove (all P < 0.01).</p><p><b>CONCLUSION</b>Both whole body MRI and diffusion-weighted MRI have a relative high sensitivity in detecting intranodal lesions for patients with lymphoma, showing a certain value in clinical application.</p>

In vivo detection of Alzheimer senile plaques by MR microscopy in transgenic mice / 中华放射学杂志

Objective MR microscopy technique was used to study the visualization of senile plaque deposition in brains of the Alzheimer disease(AD)transgenic mice.Methods Two transgenic mice and 2 wild type mice at the age of 17 months were scanned in vivo using T_2 weighted image.After MR imaging,the brains were cut serially and immunostained according to the orthogonal pilot images.MR T_2 weighted images and immunohistological images of the senile plaque were observed and matched.Results The MR images showed that some black spots were visible in the hippocampus and cerebral cortex of the AD transgenic mice and some spots were consistent with the senile plaques on immunohistological sections.There were no spots in the MR images and the immunohistological sections of the wild type mice.Conclusion It is possible that MR microscopy can be used to detect the deposition of the senile plaque and diagnose AD specifically.

Predictability of multi-slice CT perfusion in the restorability of renal function of hydronephrotic kidneys / 中华放射学杂志

Objective To evaluate the predictability of MSCT perfusion in the restorability of renal function of hydronephrotie kidneys with unilateral partial ureteric obstructed rabbit model as to explore a method to predict the restorability of renal function of hydronephrotic kidneys and to investigate the changes of MSCT perfusion parameters during the course of the restore of renal function.Methods Establish a unilateral partial ureteric obstructed rabbits hydronephrotie model.Hydronephrotie rabbits were grouped as control,2,4 and 8 week(G_2w,G_4w and G_8w)after obstruction and the later 3 groups of rabbits were reared for further 4 weeks after the obstruction was released.MSCT perfusion scanning was performed and the specimen was made into histological slices with HE staining.Results BF and BV value of renal cortex and medulla of G_2w after obstruction [(864?32)ml?100 g~(-1)?min~(-1),(19.5?0.9)ml/100 g (cortex ); (182.1?7.5)ml?100g~(-1)?min~(-1),(8.37?0.51)ml/100g(medulla)]was released restored in substance and approached that of control[(899?63)ml?100g~(-1)?min~(-1),(21.6 + 1.4)ml/100 g (cortex);(193.5?16.5 )ml?100g~(-1)?min~(-1),(8.50?0.54 )ml/100 g (medulla)]while there was no significant restore in that of G_4w and G_8w after obstruction[(525?15)ml?100g~(-1)?min~(-1),(12.8? 0.6)ml/100g (G_4 w);(512?10)ml?100g~(-1)?min~(-1),(9.4?1.0)ml/100 g (G_8w)] was released. Histologically,there was a positive correlation between the duration of obstruction and the seriousness of pathologic changes.Conclusion MSCT perfusion can provide information not only morphologically but also about renal perfusion of hydronephrotic kidneys.