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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 past findings confirm that the Rectus Capitis Posterior minor (RCPmi) is connected to the cervical spinal dura mater via the Myodural Bridge (MDB) through the posterior antlanto-occipital interspace. It is hypothesized to perform some functions. Furthermore, some clinical studies found that the pathology of RCPmi might be related to chronic headaches. But few studies were related to the morphological parameters of the RCPmi. It would be conducive to performing clinical researches on the RCPmi and MDB. To explore the optimal section for measuring the RCPmi by MRI and provide imaging anatomy parameters of the RCPmi for clinical research. The RCPmi was measured in the dissection of 10 formalin-fixed cadaver specimens. The morphological parameters of the RCPmi were obtained. Based on these parameters, T2-weighted images of the RCPmi were collected from 109 healthy adults by using the MRIs with different oblique sagittal scanning angles. The parameters of length and area of the RCPmi on the scanning sections were measured using MRI workstation and Mimics software. The length of RCPmi reached a maximum at 30 degrees scanning leaned from the posterior median line through the dens of the axis in oblique sagittal section. At this scanning section, the length of RCPmi was 21.2 ± 2.6 mm in males and 19.3 ± 2.4 mm in females and the area of RCPmi was 91.9 ± 27.2 mm2 in males and 73.3 ± 22 mm2 in females. These parameters of RCPmi were present with significant gender differences (P < 0.05) but was not age related. Thirty degrees leaned from the median line was suggested to be the optimum scanning angle to display the RCPmi in oblique sagittal section. The reference values of length and area of the RCPmi were established for studies of hypertrophy or amyotrophy of the RCPmi.

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 support quality of service (QoS) management on current Internet working with best effort, we bring forth a systematic approach for end-to-end QoS diagnosis and quantitative guarantee. For QoS diagnosis, we take contexts of a service into consideration in a comprehensive way that is realized by exploiting causal relationships between a QoS metric and its contexts with the help of Bayesian network (BN) structure learning. Context discretization algorithm and node ordering algorithm are proposed to facilitate BN structure learning. The QoS metric is diagnosed to be causally related to its causal contexts, and the QoS metric can be quantitatively guaranteed by its causal contexts. For quantitative QoS guarantee, those causal relationships are first modeled quantitatively by BN parameter learning. Then, the QoS metric is guaranteed to certain value with a probability given its causal contexts tuned to suitable values, that is, quantitative QoS guarantee is reached. Simulations with three sequential stages: context discretization, QoS diagnosis and quantitative QoS guarantee, on a peer-to-peer (P2P) network, are discussed and our approach is validated to be effective.

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.

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.

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.

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.