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Magnetic resonance imaging (MRI) plays an important role in clinical diagnosis, but it is susceptible to metal artifacts. The generative adversarial network GatedConv with gated convolution (GC) and contextual attention (CA) was used to inpaint the metal artifact region in MRI images.MRI images containing or near the teeth of 70 patients were collected, and the scanning sequence was a T1-weighted high-resolution isotropic volume examination sequence. A total of 10 000 slices were obtained after data enhancement, of which 8000 slices were used for training. MRI images were normalized to [-1,1]. Based on the randomly generated mask, U-Net, pix2pix, PConv with partial convolution, and GatedConv were used to inpaint the artifact region of MRI images. The mean absolute error (MAE) and peak signal-to-noise ratio (PSNR) for the mask were used to compare the results of these methods. The inpainting effect on the test dataset using dental masks was also evaluated. Besides, the artifact area of clinical MRI images was inpainted based on the mask sketched by physicians. Finally, the earring artifacts and artifacts caused by abnormal signal foci were inpainted to verify the generalization of the models.GatedConv could directly and effectively inpaint the incomplete MRI images generated by masks in the image domain. For the results of U-Net, pix2pix, PConv, and GatedConv, the masked MAEs were 0.1638, 0.1812, 0.1688, and 0.1596, respectively, and the masked PSNRs were 18.2136, 17.5692, 18.2258, and 18.3035 dB, respectively. Using dental masks, the results of U-Net, pix2pix, and PConv differed more from the real images in terms of alveolar shape and surrounding tissue compared with GatedConv. GatedConv could inpaint the metal artifact region in clinical MRI images more effectively than the other models, but the increase in the mask area could reduce the inpainting effect. Inpainted MRI images by GatedConv and CT images with metal artifact reduction coincided with alveolar and tissue structure, and GatedConv could successfully inpaint artifacts caused by abnormal signal foci, whereas the other models failed. The ablation study demonstrated that GC and CA increased the reliability of the inpainting performance of GatedConv.MRI images are affected by metal, and signal void areas appear near metal. GatedConv can inpaint the MRI metal artifact region in the image domain directly and effectively and improve image quality. Medical image inpainting by GatedConv has potential value for tasks, such as positron emission tomography (PET) attenuation correction in PET/MRI and adaptive radiotherapy of synthetic CT based on MRI.

BACKGROUND Congenital nephrogenic diabetes insipidus (CNDI) is a rare hereditary renal disorder that is caused by mutations in AVPR2 or aquaporin 2 (AQP2). Up to now, there are few reports about CNDI in neonates. Early clinical manifestations of CNDI in neonates are atypical. A lack of understanding of the disease by clinicians causes frequent misdiagnoses or missed diagnoses, which may result in failure to administer treatments in time and ultimately leads to severe complications. In this study, clinical data of a case of AVPR2 gene mutation-induced CNDI, which was confirmed by genetic testing, were retrospectively analyzed to improve our understanding of this disease. CASE SUMMARY On February 1, 2020, a male neonate was hospitalized 17 d after birth due to a 7 d period of pyrexia. The patient’s symptoms included recurrent pyrexia, hypernatremia and hyperchloremia, which were difficult to treat. The patient was fed on demand, and water was additionally provided between milk intakes. A combination treatment of hydrochlorothiazide and amiloride was administered. After the treatment, body temperature and electrolyte levels returned to normal, the volume of urine was significantly reduced and the patient was subsequently discharged. Genetic tests confirmed that the patient carried the AVPR2 gene missense mutation c.541C>T (P.R181C), and the patient’s mother carried a heterozygous mutation at the same locus. After clinical treatment with a combination of hydrochlorothiazide and amiloride, the body temperature and electrolyte levels returned to normal. Up until the most recent follow-up examination, normal body temperature, electrolyte levels and growth and development were observed. CONCLUSION CNDI in the neonatal period is rare, and its clinical manifestations are unspecific with some patients merely showing recurrent fever and electrolyte disturbance. Genetic testing of AVPR2 and AQP2 can be used for screening and genetic diagnosis of CNDI.

BACKGROUND: Many hospitals favor magnetic resonance imaging (MRI) as the preferred diagnostic method to detect anal fistula, trans-fistula contrast-enhanced ultrasound (CEUS) for the diagnosis of anal fistula have attracted the attention of investigators worldwide. This study aimed to investigate the efficacy of trans-fistula contrast-enhanced endoanal ultrasound (CEUS) and magnetic resonance imaging (MRI) in the diagnosis of anal fistula. METHODS: Ninety-eight patients undergoing trans-fistula CEUS and MRI were retrospectively analyzed. The fistulous trend and positional relation between the fistula, levator ani muscle, and sphincter (Parks classification), as well as the numbers of fistulous branches, number and position of the fistula, and distance between internal opening and anal edge were recorded. These parameters were compared with the postoperative results. RESULTS: There were no significant statistical differences (P>0.05) in the accuracy rates of trans-fistula CEUS and MRI, respectively, in terms of Parks classification (90.82%, 92.86%), branches (89.19%, 81.08%), internal openings (92.68%, 89.43%), and internal openings ≥3 cm from the anal edge (85.71%, 92.86%). However, we observed a significant difference in terms of internal openings

Background Preoperative prediction of early recurrence (ER) of hepatocellular carcinoma (HCC) plays a critical role in individualized risk stratification and further treatment guidance. Purpose To investigate the role of radiomics analysis based on multiparametric MRI (mpMRI) for predicting ER in HCC after partial hepatectomy. Study type Retrospective. Population In all, 113 HCC patients (ER, n = 58 vs. non-ER, n = 55), divided into training (n = 78) and validation (n = 35) cohorts. Field strength/sequence 1.5T or 3.0T, gradient-recalled-echo in-phase T1 -weighted imaging (I-T1 WI) and opposed-phase T1 WI (O-T1 WI), fast spin-echo T2 -weighted imaging (T2 WI), spin-echo planar diffusion-weighted imaging (DWI), and gradient-recalled-echo contrast-enhanced MRI (CE-MRI). Assessment In all, 1146 radiomics features were extracted from each image sequence, and radiomics models based on each sequence and their combination were established via multivariate logistic regression analysis. The clinicopathologic-radiologic (CPR) model and the combined model integrating the radiomics score with the CPR risk factors were constructed. A nomogram based on the combined model was established. Statistical tests Receiver operating characteristic (ROC) curve analysis was used to evaluate the discriminative performance of each model. The potential clinical usefulness was evaluated by decision curve analysis (DCA). Results The radiomics model based on I-T1 WI, O-T1 WI, T2 WI, and CE-MRI sequences presented the best performance among all radiomics models with an area under the ROC curve (AUC) of 0.771 (95% confidence interval (CI): 0.598-0.894) in the validation cohort. The combined nomogram (AUC: 0.873; 95% CI: 0.756-0.989) outperformed the radiomics model and the CPR model (AUC: 0.742; 95% CI: 0.577-0.907). DCA demonstrated that the combined nomogram was clinically useful. Data conclusion The mpMRI-based radiomics analysis has potential to predict ER of HCC patients after hepatectomy, which could enhance risk stratification and provide support for individualized treatment planning. Evidence level 4. Technical efficacy Stage 4.

The objective was to introduce a new endoscopic technique‐interspinous plasty for low back pain from Baastrup's disease; based on clinical manifestations, imaging findings and diagnostic test, to discuss a detailed diagnostic procedure for Baastrup's disease; and to explore the mechanism of interspinous plasty in pain relief. To our knowledge, there is no report about the results of endoscopic lumbar technique for Baastrup's disease. This study described the successful full‐endoscopic surgical treatment for Baastrup's disease, providing a brand‐new therapeutic method for patients. Clinical manifestations, imaging findings, including X‐ray, computed tomography (CT) and magnetic resonance imaging, and a “positive” diagnostic test with local anesthetic were used to confirm Baastrup's disease in the three included patients. The interspinous plasty procedure, which aimed to recover a physiological gap between the adjacent spinous processes, was performed by full‐endoscopic resection of marginal osteophytes. The removal of local inflamed tissue and reducing inflammation via intraoperative saline irrigation also lead to pain relief. Clinical outcomes included visual analog scale (VAS) for low back pain and the Oswestry Disability Index (ODI). The distance between the adjacent spinous processes was measured from the preoperative and postoperative CT scan. We calculated and recorded the difference between preoperative and postoperative measurements. Technical procedures and advantages of interspinous plasty are introduced. The three patients showed improvement in terms of the postoperative VAS of low back pain (from 8 to 2, from 7 to 1 and from 8 to 2) and ODI (from 68.9% to 33.3%, from 77.8% to 28.9% and from 71.1% to 28.9%, respectively) at the 12‐month follow‐up. Compared postoperative ODI index, the ODI index increased from 26.7% to 33.3% and from 24.4% to 28.9% in two of the cases at the 12‐month follow‐up. At 1 week, CT confirmed an obvious reduction in the marginal osteophytes between the adjacent spinous processes. Compared with those on preoperative CT images, the distance between adjacent spinous processes on postoperative CT was enlarged from 1 to 4 mm, and a repeated CT scan 3 months later reconfirmed little recrudescent osteoproliferation. In selected cases, full‐endoscopic surgical treatment for chronic mechanical back pain as part of the phenomena of Baastrup's disease may be beneficial. The operations in this study were performed under local anesthesia, with satisfactory early clinical outcomes and a low incidence of complications or adverse events. This may be a feasible therapeutic method or an alternative option for patients who cannot tolerate general anesthesia surgery., The interspinous plasty, aimed to recover a physiological gap between the spinous processes, were performed by full‐endoscopic resecting marginal osteophytes. Our study was designed to describe the successful full‐endoscopic approach for low back pain from Baastrup's disease, providing a brand‐new therapeutic method for patients.

To compare outcomes of anterior-only (AO), posterior-only (PO), and anteroposterior (AP) surgical approaches for treatment of dystrophic cervical kyphosis in patients with neurofibromatosis 1 (NF1).This retrospective observational study included 81 patients with dystrophic cervical kyphosis secondary to NF1. Length of kyphosis, duration of halo traction, Cobb angle, C2-7-sagittal vertical axis (SVA), T1 slope, Neck Disability Index score, and postoperative complications were evaluated before and, if possible, after each surgical approach.AP approach provided the best outcomes (average spinal Cobb angle was corrected from 61.2 ± 9.1° to 5.7 ± 3.2°, P0.05); there was no significant difference between AO and PO approaches (P0.05). With regard to cervical sagittal balance, AP approach had the most improvements of C2-7-SVA (mean C2-7-SVA was corrected from 3.2 ± 9.2 mm to 12.8 ± 2.6 mm, P0.05); the difference between AO and PO approaches was not significant (P0.05). T1 slope results were similar to C2-7-SVA. Neck Disability Index score of all patients improved significantly after surgery (P0.05); specifically, patients who had an AP approach constituted the largest portion of the satisfied patient group. Postoperative junctional kyphosis occurred in 11 patients (1 AP approach, 6 AO approach, 4 PO approach); these findings correlated with patients with ≤5 fused segments.AP approach surgery provided the best correction of dystrophic cervical kyphosis and sagittal balance for patients with NF1. Patients undergoing an AP approach were more satisfied with their outcomes. Junctional kyphosis can be prevented effectively using an AP approach in patients with5 fused segments.

The most common methods for three-dimensional reconstruction of peripheral nerve fascicles include histological and radiology techniques. Histological techniques have many drawbacks including an enormous manual workload and poor image registration. Micro-magnetic resonance imaging (Micro-MRI), an emerging radiology technique, has been used to report results in the brain, liver and tumor tissues. However, micro-MRI usage for obtaining intraneural structures has not been reported. The aim of this study was to present a new imaging method for three-dimensional reconstruction of peripheral nerve fascicles by 1T micro-MRI. Freshly harvested sciatic nerve samples from an amputated limb were divided into four groups. Two different scanning conditions (Mannerist Solution/GD-DTPA contrast agent, distilled water) were selected, and both T1 and T2 phases programmed for each scanning condition. Three clinical surgeons evaluated the quality of the images via a standardized scale. Moreover, to analyze deformation of the two-dimensional image, the nerve diameter and total area of the micro-MRI images were compared after hematoxylin-eosin staining. The results show that rapid micro-MRI imaging method can be used for three-dimensional reconstruction of the fascicle structure. Nerve sample immersed in contrast agent (Mannerist Solution/GD-DTPA) and scanned in the T1 phase was the best. Moreover, the nerve sample was scanned freshly and can be recycled for other procedures. MRI images show better stability and smaller deformation compared with histological images. In conclusion, micro-MRI provides a feasible and rapid method for three-dimensional reconstruction of peripheral nerve fascicles, which can clearly show the internal structure of the peripheral nerve.

Yunbin Xiao,1,* Zuan Tao Lin,2,* Yanmei Chen,1 He Wang,1 Ya Li Deng,2 D Elizabeth Le,3 Jianguo Bin,1 Meiyu Li,1 Yulin Liao,1 Yili Liu,1 Gangbiao Jiang,2 Jianping Bin1 1State Key Laboratory of Organ Failure Research, Division of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, People’s Republic of China; 2Department of Pharmaceutical Engineering, South China Agricultural University, Guangzhou, People’s Republic of China; 3Cardiovascular Division, Oregon Health and Science University, Portland, OR, USA *These authors contributed equally tothis work Abstract: Magnetic resonance imaging (MRI) contrast agents based on chitosan derivatives have great potential for diagnosing diseases. However, stable tumor-targeted MRI contrast agents using micelles prepared from high molecular weight chitosan derivatives are seldom reported. In this study, we developed a novel tumor-targeted MRI vehicle via superparamagnetic iron oxide nanoparticles (SPIONs) encapsulated in self-aggregating polymeric folate-conjugated N-palmitoyl chitosan (FAPLCS) micelles. The tumor-targeting ability of FAPLCS/SPIONs was demonstrated in vitro and in vivo. The results of dynamic light scattering experiments showed that the micelles had a relatively narrow size distribution (136.60±3.90 nm) and excellent stability. FAPLCS/SPIONs showed low cytotoxicity and excellent biocompatibility in cellular toxicity tests. Both in vitro and in vivo studies demonstrated that FAPLCS/SPIONs bound specifically to folate receptor-positive HeLa cells, and that FAPLCS/SPIONs accumulated predominantly in established HeLa-derived tumors in mice. The signal intensities of T2-weighted images in established HeLa-derived tumors were reduced dramatically after intravenous micelle administration. Our study indicates that FAPLCS/SPION micelles can potentially serve as safe and effective MRI contrast agents for detecting tumors that overexpress folate receptors. Keywords: superparamagnetic iron oxide, magnetic resonance imaging, polymeric micelles, folate receptors, tumor-targeted MRI, N-palmitoyl chitosan

BACKGROUND T1ρ and T2* relaxation times are capable of providing information about early biochemical changes in intervertebral disk degeneration (IVDD). The purpose of this study was to assess and compare T1ρ and T2* mapping in IVDD with reference to Pfirrmann grade. MATERIAL AND METHODS Lumbar sagittal T2-weighted, T1ρ and T2* relaxation MRI were performed at 3.0T in 42 subjects covering discs L1-L2 to L5-S1. All the discs were morphologically assessed according to the Pfirrmann grade. Regions of interest (ROIs) were drawn over the T1ρ and T2*mappings, including nucleus pulposus (NP) and annulus fibrosus (AF). Wilcoxon signed rank test, Kruskal-Wallis test, and Spearman rank correlation were performed. RESULTS The difference in T1ρ and T2* values between NP and AF were highly significant (P

The suboccipital muscles are connected to the upper cervical spinal dura mater via the myodural bridges (MDBs). Recently, it was suggested that they might work as a pump to provide power for cerebrospinal fluid (CSF) circulation. The purpose of this study was to investigate effects of the suboccipital muscles contractions on the CSF flow. Forty healthy adult volunteers were subjected to cine phase-contrast MR imaging. Each volunteer was scanned twice, once before and once after one-minute-head-rotation period. CSF flow waveform parameters at craniocervical junction were analyzed. The results showed that, after the head rotations, the maximum and average CSF flow rates during ventricular diastole were significantly increased and the CSF stroke volumes during diastole and during entire cardiac cycle were significantly increased. This suggested that the CSF flow was significantly promoted by head movements. Among the muscles related with head movements, only three suboccipital muscles are connected to the upper cervical spinal dura mater via MDBs. It was believed that MDBs might transform powers of the muscles to CSF. The present results suggested that the head movements served as an important contributor to CSF dynamics and the MDBs might be involved in this mechanism.

Objective We aimed to investigate the morphological changes and potential correlation between chronic headaches and the rectus capitis posterior minor muscle (RCPmi). Methods Comparison of RCPmi between patients with chronic headaches and healthy adult volunteers were collected using magnetic resonance imaging (MRI) and Mimics software. Results Among the 235 MRI images analyzed, the data between the two groups were considered statistically significant. The number of males was larger than that of females ( p Conclusions Chronic headaches were correlated with the RCPmi. Patients with chronic headaches suffered from more obvious hypertrophy than that of the control group. Additionally, it was supposed that RCPmi hypertrophy may be one pathogenesis of the chronic headaches.

To determine the association between perioperative anesthetic exposure and neurodevelopmental status at age 1 year old baby underwent complex cardiac surgery. One hundred and fifteen infants were selected from Sichuan People's Hospital. A cohort study was conducted on neonates who underwent complex cardiac surgery. The babies were performed brain MRI before the operation and 7 days after the operation, and 12-month neurodevelopmental testing was carried out with Bayley Scales of Infant and Toddler Development (the third Edition, Bayley-III). Doses of volatile anesthetics (VAA), benzodiazepines, and opioids were determined during the 12 months. The association between peri-operative anesthetic exposure and 12-month neurodevelopmental status were analyzed. A total of 92 infants were enrolled for the final analysis. Their Bayley-III scores of cognitive, language, and movement were as follows: 104.2 ± 14.7, 85.6 ± 11.3, and 86.9 ± 13.5, respectively. MRI results showed that 17 infants showed pre-operative brain injury and 25 infants showed new post-operative injury. After performing the analysis of stepwise multivariable linear regression, MRI showed the factors affecting neurodevelopment of newborn include the new post-operative injury, higher VAA exposure, fentanyl dose, benzodiazepine dose, ICU length of stay, pre-operative mean regional cerebral oxygen saturation (rSO₂), and abnormal chromosomes. VAA exposure and ICU length of stay are associated with poor neurodevelopmental scores at 12 months of age. Further studies need to identify the potential modifiable factors in the peri-operative care of neonates to improve neurodevelopmental outcomes.目的：探讨新生儿心脏手术的围手术期麻醉暴露与1岁时的神经发育结果的相关性。方法：选取四川省人民医院行心脏手术的新生儿115例，纳入队列研究，于术前和术后7 d行大脑磁共振(MRI)，记录围手术期挥发性麻醉药、苯二氮卓类与阿片类药物使用情况，患儿1岁时应用贝利婴幼儿发展量表评估患儿的认知、语言和运动情况，在矫正其他协变量基础上分析它们的相关性。结果：共有92例患儿被纳入研究，患儿1岁时贝利婴幼儿发展量表认知、语言和运动的分值分别为104.2±14.7，85.6±11.3和86.9±13.5；术前MRI显示颅脑损伤17例，术后MRI显示颅脑损伤25例。多重线性回归分析显示与1岁神经发育结果相关的因素包括MRI显示术后脑损伤、挥发性麻醉药的最低肺泡有效浓度、芬太尼总质量浓度、苯二氮卓类总质量浓度、ICU住院时间、术前平均区域脑氧饱和度和染色体异常。结论：挥发性麻醉药暴露、术后MRI显示脑损伤以及长ICU住院时间是患儿1岁时神经发育预后差的影响因素。需要采取针对性的措施，降低围手术期致神经损伤的危险因素。.

To provide practical anatomic data for the imaging diagnosis and surgical treatment of adrenal disease, we investigated the anatomy of the adrenal gland and its relationships to regional structures using 31 sets of serial coronal sections of upper abdomen of Chinese adult cadavers and correlated coronal magnetic resonance (MR) images of ten upper abdomens of adult healthy volunteers and coronal reconstructed multislice spiral computed tomography (MSCT) images of five patients without lesions in the adrenal gland. The adrenal glands were visualized mainly on the successive coronal sections between 18 mm anterior to the posterior margin of inferior vena cava and 24 mm posterior to the posterior margin of inferior vena cava. In general, the left adrenal gland was visualized two sections earlier than the right adrenal gland. On the plane through the anterior parts of bilateral renal hili (A18), the appearance rate of bilateral adrenal glands was 100%, and the maximal measurements of bilateral adrenal glands were visualized. The length, width, thickness of right adrenal body, thickness of medial limb and lateral limb were, respectively, 34.02 +/- 2.12 mm, 10.91 +/- 0.89 mm, 5.82 +/- 0.26 mm, 2.78 +/- 0.08 mm, 2.62 +/- 0.06 mm, whereas the measurements of left adrenal gland were 28.31 +/- 2.46 mm, 18.40 +/- 1.06 mm, 6.84 +/- 0.24 mm, 3.02 +/- 0.08 mm, 2.86 +/- 0.07 mm, respectively. The coronal plane has superior advantage in showing the bilateral adrenal glands. The shapes of adrenal glands are various, whereas the range of adrenal thickness is quite narrow. The thickness of adrenal medial and lateral limbs, especially the thickness of lateral limb are useful for the diagnosis of the bilateral adrenocortical disease.

BACKGROUND During follow-up for patients with cervical carcinoma, elevation of serum squamous cell carcinoma antigen (SCC-Ag) levels in the absence of detectable recurrent lesions presents a diagnostic and therapeutic challenge. In the current prospective study, the authors evaluated the use of fluorine-18-labeled fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) to detect disease recurrence in this setting. METHODS Women with cervical carcinoma who experienced complete responses to primary treatment or salvage therapy and who had no evidence of recurrent disease as detected by conventional methods but had serum SCC-Ag levels ≥ 2.0 ng/mL on 2 consecutive occasions were eligible for the study. PET was performed within 2 weeks after the completion of conventional studies for the assessment of recurrence. RESULTS Twenty-seven consecutive patients were registered for the current study. PET findings were positive for 19 patients: 14 who had a distant lesion or lesions, 2 who had a local lesion or lesions, and 3 who had both local and distant lesions. Of these 19 patients, 17 were confirmed to have recurrent disease; the remaining two were found to be free of disease but had severe anthracosis in the PET-positive mediastinal lymph nodes. Seven of the eight patients with negative PET findings were not found to have recurrent disease on follow-up. Overall, PET detected FDG-avid lesions in 17 (94%; P < 0.001) of the 18 patients with recurrent disease. Seven of these 18 patients received therapy with curative intent; complete control was achieved in 6, four of whom currently are alive and free of disease. The addition of PET in the current setting curbed the use of futile curative therapy and significantly increased overall survival for patients in the current cohort compared with a historical group of 30 consecutive patients who had elevated SCC-Ag levels as a first sign of recurrence. CONCLUSIONS PET expedited the detection of recurrent cervical carcinoma in patients with unexplained elevation of SCC-Ag levels. Such expedited detection may have positive effects on patient survival. Cancer 2004. © 2004 American Cancer Society.

Uninephrectomy would induce compensatory hypertrophy in the remaining kidney. We investigated the relationship between changes in renal parenchymal volume (RPV) and renal function after nephrectomy in living kidney donors. From July 2011 and January 2012, 45 kidney donors were enrolled in this study. Magnetic resonance scanning was performed before surgery, 3 and 7 days postoperatively, and RPV was calculated through disc summarize methods. Participants were followed up for 1 year. The RPV of the remaining kidney was 118.06 ± 23.51 cm3 and then increased by 21.23 % to 143.13 ± 25.52 cm3 at 3 days and by 24.17 % to 146.60 ± 25.86 cm3 at 7 days. Multivariate regression analysis showed that preoperative RPV is positively related to its initial function (p = 0.037); the RPV at 7 days is directly related to its initial, preoperative size (p

Background Increasing evidence suggests seizures cause blood–brain barrier (BBB) dysfunction including decreased seizure threshold and higher onset potential of future seizures. However, the mechanisms underlying BBB damage in seizures remains poorly understood. Evidence in human and animal models shows BBB disruption is associated with activation of matrix metalloproteinase-9 (MMP-9) after cerebral ischemia and inflammation. The objective of this study was to determine whether MMP-9 concentrations in cerebral spinal fluid (CSF) are associated with BBB disruption in patients after epileptic seizures. Methods Thirty-one patients with generalized tonic-clonic (GTC) seizures were included in the study: 20 had recurrent GTC seizures (RS), and 11 had a single GTC seizure (SS) episode. Twenty-five adult non-seizure patients were used as controls. CSF samples were collected by lumbar puncture within 24 h after seizure cessation (range: 3–15 h, mean 6.2 h). CSF MMP-9 levels were determined by an enzyme-linked immunosorbent assay (ELISA). MMP enzyme activity was measured by gelatin zymography. The CSF/serum albumin ratio (albumin quotient, QAlb) was used as a measure of blood–brain barrier permeability. Results We found significantly higher CSF MMP-9 concentrations in seizure patients compared with controls (P < 0.001). CSF MMP-9 levels and QAlb values were higher in RS patients compared with SS and controls. Moreover, CSF MMP-9 concentration showed strong correlation between QAlb values (r = 0.76, P < 0.0001) and between CSF leukocyte counts (r = 0.77, P < 0.0001) in patients after seizures. Gelatin zymography showed MMP-9 proteolytic activity only in GTC seizure patients. Conclusions Our results suggest MMP-9 plays a role in BBB dysfunction, characterized by invasion of leukocytes into the CSF during seizures.

Purpose To obtain the thin coronal sectional anatomic dataset of the liver by using digital freezing milling technique. Methods The upper abdomen of one Chinese adult cadaver was selected as the specimen. After CT and MRI examinations verification of absent liver lesions, the specimen was embedded with gelatin in stand erect position and frozen under profound hypothermia, and the specimen was then serially sectioned from anterior to posterior layer by layer with digital milling machine in the freezing chamber. The sequential images were captured by means of a digital camera and the dataset was imported to imaging workstation. Results The thin serial section of the liver added up to 699 layers with each layer being 0.2 mm in thickness. The shape, location, structure, intrahepatic vessels and adjacent structures of the liver was displayed clearly on each layer of the coronal sectional slice. CT and MR images through the body were obtained at 1.0 and 3.0 mm intervals, respectively. Conclusion The methodology reported here is an adaptation of the milling methods previously described, which is a new data acquisition method for sectional anatomy. The thin coronal sectional anatomic dataset of the liver obtained by this technique is of high precision and good quality.

To obtain the three dimensional visualization model with normal measurements of fetal brain in the second trimester and analyze the developmental changes with gestational age (GA), sexual dimorphisms and cerebral asymmetries.The brains of 69 fetal specimens of 12 - 22 weeks GA were scanned by 7.0T magnetic resonance imaging (MRI). The developing structures were analyzed and a three dimensional visualization model was rebuilt with Amira 4.1 software.Most sulci, except for postcentral and intraparietal sulcus, were present until 22 weeks GA. And none developed secondary branches. Laminar organization, described as early as 12 weeks GA, was delineated as layers with different signal intensities and became typical after 16 weeks GA. Basal nuclei was distinctly visible. Brains had different growth rates linearly increasing with GA. But neither sexual dimorphisms nor cerebral asymmetries was detected.The initial developmental stage of fetal brain occurs at 12 - 22 weeks GA. The developing structures may be distinctly visualized on 7.0T post-mortem MRI. And the three dimensional visualization model aids greatly in the precise cognition of immature brain.

Since the acquired images are often distorted by noise resulting from various experimental and other sources (e.g., the RF tagging effects) in magnetic resonance imaging (MRI), removing noise is a very important work and at the same time useful information should be well preserved. In this paper, a novel, fast denoising algorithm has been proposed to make tradeoff between reducing noise and enlarging contrast of MRI images. Finally the computed results are in good agreement with our theoretical prediction.

The purpose of this study was to explore the anatomical complexity and adjacent relationships of the sellar region in thin continuous sections so as to provide intimate morphological data for imaging diagnosis and surgical operations of the diseases in this region. After CT and MR examination verifying no brain lesions, one normal cadaver head was selected for this study from four Chinese adult male cadavers. After being embedded and frozen, the head was sliced into serial sections at 0.1 mm intervals in the transverse plane with SKC 500 computerized freezing milling machine. Then the serial transverse sections were photographed by a high-resolution digital camera and saved in the computer. Subsequently, the anatomic structures of the sellar region on the thin transverse sections were investigated and correlated with the MR images of the specimen as well as in vivo MR images, which were obtained from 20 normal Chinese male adult volunteers by a 3.0 T GE MR scanner. The base lines of the sectioning and the MR scan were all parallel to the AC-PC line. A total of 320 transverse sections and 10-12 transverse MR images related with the sellar region were obtained, respectively. We investigated the sectional anatomy of the sellar region and divided it into three parts: supra hypophysial area, hypophysial area and infra hypophysial area. The cavernous sinus was a venous passage full of blood and it could be divided into four interspaces according to its position relation with the internal carotid artery. The third, fourth, sixth cranial nerves and trigeminal branches ophthalmic nerve, maxillary nerve displayed from the anterior to the posterior in the lateral wall of cavernous sinus in transverse planes. Comparing continuous thin sections with MR images offers a better understanding of the complex anatomical structures and provides practical submillimeter anatomical data for imaging diagnosis and clinical treatment in this region.

The tremendous potential of chemical exchange saturation transfer (CEST) agents as an emerging class of magnetic resonance imaging contrast media has been demonstrated in recent years. In a CEST experiment, a high CEST contrast is always welcome. However, when the exchange rate is low, which may happen in exchangeable solute protons of low concentration, it is usually hard to obtain an excellent CEST efficiency. Recently, we noted that the intermolecular multiple quantum coherence signal is more sensitive to the changes of the magnetization magnitude than a conventional single quantum coherence signal. Consequently, it may be easier when used in obtaining a CEST contrast. In this note, a modified COSY (two-dimensional correlated spectroscopy) revamped with an asymmetric Z-gradient echo detection (CRAZED) sequence combined with an off-resonance saturation pulse followed by a standard spin-echo imaging sequence was designed to obtain a better CEST contrast image based on the intermolecular double quantum coherence method. An analytical expression was derived from a dipolar field theory. Experiments were performed on an agar-glucose phantom, and the results demonstrate the feasibility of our method.

This study was undertaken to explore the anatomic features and adjacent relationships of the pineal region in thin coronal sections. After CT and MR examination verifying no brain lesions, one normal cadaver head was selected for this study from three Chinese adult male cadavers. After being embedded and frozen, the head was sliced into serial sections at 0.1 mm intervals in the coronal plane with SKC 500 computerized freezing milling machine. Then the serial coronal sections were photographed by a high-resolution digital camera and saved in the computer. Subsequently, the anatomic structures of the pineal region on the thin coronal sections were investigated and correlated with in vivo MR images, which were obtained from ten normal Chinese male adult volunteers by a 3.0 T GE scanner. The base lines of the sectioning and the MR scan were all perpendicular to the AC-PC line. A total of 355 coronal sections and 21-23 in vivo coronal MR images related with the pineal region were obtained, respectively. From anterior to posterior, the shape of the pineal region changed from an inverted triangle to a trapezoid and a triangle gradually, and the anatomic details could be depicted clearly in the thin sectional anatomy images in sub-millimeter. Via the comparison, some micro-anatomic structures of the pineal region that cannot be discriminated clearly or missed in the thick sections or MR images were identified. The contrast of the computerized freezing milling technique with the MRI enhanced our ability to comprehend the complex anatomy of the pineal region and to improve the imaging diagnosis and surgical treatments of minute diseases in this region.

Contribution of chemical shift to intermolecular multiple-quantum coherence (iMQC) imaging signals in two-component systems was simulated and discussed using an efficient numerical algorithm based on the Bloch equations with an additional nonlinear term describing distant dipolar field. Numerical simulation switches back and forth between real and Fourier spaces to handle dipolar field effects in three-dimensional sample. The iMQC signals of each component of two-component systems can be obtained respectively when the second pulse of the CRAZED pulse sequence is selective. Simulation results show that chemical shift provides an edge detection method to regions containing spins with chemical shift offset and selected by the second RF pulse, and different gray value is related to different chemical shift in detected regions. These results indicate that chemical shift may provide new imaging information helpful for iMQC magnetic resonance imaging.

To examine change of the apparent relaxation rate R2* values in living kidney donors after uninephrectomy using blood oxygenation level-dependent magnetic resonance imaging.Between July 2011 and January 2012, 45 kidney donors were enrolled into this study. Blood oxygenation level-dependent magnetic resonance imaging scanning was performed before surgery, 3 and 7 days postoperatively. Participants were followed up for 1 year.The R2* values in medulla (mR2*) were significantly greater than that of cortex (cR2*), both in resected kidney and remaining one. cR2* values of the remaining kidney was 17.52 ± 1.36 s(-1) and then decrease significantly by 8.97% to 15.95 ± 1.14 s(-1) at 3 days (P.001) and by 7.82% to 16.15 ± of 1.05 s(-1) at 7 days. No significant modification occurred in mR2* after surgery. Multivariate regression analysis showed that the decrease in cR2* values of the remaining kidney was positively associated with sex (r = 0.418), body surface area (r = 0.307), and preoperative cR2* values (r = 0.659). Comparing with glomerular filtration rate at 7 days, a further increment in the glomerular filtration rate was noted at 1 year in patients with cR2* values decrease of ≥ 10% at 1 week (62.63 ± 11.69 vs 56.97 ± 7.51 mL/min/1.73 m(2), P = .02) but not in the other patients (66.43 ± 10.89 vs 62.78 ± 13.74, P = .064).Kidney donation will induce early, profound oxygenation modification within the renal cortex of the remaining kidney. Donors with cR2* value decrease of ≥ 10% at 1 week have a more favorable renal function compensation at 1 year.

To investigate whether the ratio of remnant kidney volume to body weight (V/W ratio) can impact renal function in donors, 45 living kidney donors were enrolled. Kidney volume was analyzed by magnetic resonance imaging. Renal function was compared between donors with a V/W ratio of < 2.0 mL/kg (n = 23) or ≥ 2.0 mL/kg (n = 22). Donors in both V/W groups showed similar serum creatinine levels and estimated glomerular filtration rates (eGFRs) at 7 days and 1 year, whereas donors with a V/W ratio of < 2.0 mL/kg had significantly higher 24-hour urine protein levels at 1 year (0.54 ± 0.23 g/d vs. 0.33 ± 0.19 g/d, p = 0.028). Multivariate analysis revealed no correlation between the V/W ratio and eGFR at 7 days or 1 year, and a V/W ratio of < 2 mL/kg was not associated with an increased incidence of eGFR < 60 mL/min/1.73 m2 at 1 year (risk ratio 1.73, 95% confidence interval 0.10–29.47). The V/W ratio correlated inversely with 24-hour urine protein (r = −0.377, p = 0.021) at 1 year, and donors with a V/W ratio of < 2.0 mL/kg were more likely to show 24-hour urine protein >300 mg (risk ratio 1.70, 95% confidence interval 1.08–2.67) at 1 year. Donors with lower V/W ratios have higher 24-hour urinary protein levels at 1 year after transplantation. These findings suggest that the V/W ratio may be useful for kidney selection.