Brain functional connectivity and cognition in mild traumatic brain injury.

INTRODUCTION: The aim of this study was to analyze brain functional connectivity and its relationship to cognition in patients with mild traumatic brain injury (mTBI). METHODS: Twenty-five patients with mTBI and 25 healthy control subjects were studied using resting-state functional MRI (rs-fMRI). Amplitudes of low-frequency fluctuations (ALFFs) and functional connectivity (FC) were calculated and correlated with cognition. RESULTS: Compared with the normal control group, the mTBI patients showed a significant decrease in working memory index (WMI) and processing speed index (PSI), as well as significantly decreased ALFFs in the cingulate gyrus, the middle frontal gyrus and superior frontal gyrus. In contrast, the mTBI patients' ALFFs in the left middle occipital gyrus, the left precuneus, and lingual gyrus increased. Additionally, FC significantly decreased in the thalamus, caudate nucleus, and right hippocampus in the mTBI patients. Statistical analysis further showed a significant positive correlation between the ALFF in the cingulate gyrus and the WMI (R (2) = 0.423, P < 0.05) and a significant positive correlation between the FC in the left thalamus and left middle frontal gyrus and the WMI (R (2) = 0.381, P < 0.05). CONCLUSION: rs-fMRI can reveal the functional state of the brain in patients with mTBI. This finding differed from observations of the normal control group and was significantly associated with clinical cognitive dysfunction. Therefore, rs-fMRI offers an objective imaging modality for treatment planning and prognosis assessment in patients with mTBI.

Thin sectional anatomy, three-dimensional reconstruction and visualization of the heart from the Chinese Visible Human.

The research aimed to provide sectional anatomic and three-dimensional (3D) virtual anatomic bases for imaging diagnosis and surgical operation by the use of data from the heart of the first Chinese digitized Visible Human. Data from the series of thin sections of the heart were analyzed and input into an SGI workstation, and 3D reconstruction and virtualization of the heart were performed. Each image of sectional anatomy was clear and the 3D structures of the heart were reconstructed in their entirety. All reconstructed structures can be displayed by multiple structural and color modes, individually or jointly, and can be rotated continuously in any plane. The model of the virtual heart clearly showed fine structures of the heart in random orientation. The dataset of the sectional anatomy provides a fine and integrated morphologic base for imaging diagnosis. The 3D reconstructed images clearly show the internal and entire structures of the heart.

The pre-styloid compartment of the parapharyngeal space: a three-dimensional digitized model based on the Chinese Visible Human.

To build a digitized visible model of the parapharyngeal space of the Chinese Visible Human and to provide a sectional anatomic basis for radiological and clinical diagnosis of the parapharyngeal space, sectional anatomy data of the parapharyngeal space were selected from the Chinese Visible Human male and female to compare with MR imaging findings in the axial planes. From these data the parapharyngeal space and surrounding structures were segmented. They were then reconstructed in three dimensions on PC. In the axial planes of the sectional anatomy and MR imaging, the shape, content and relations of the parapharyngeal space were clearly displayed and the dominant plane for showing the parapharyngeal space was elicited. The three-dimensional reconstructed images displayed perfectly the anatomic relationships of the parapharyngeal space, parotid, muscles, mandible and vessels. All reconstructed structures can be displayed singly, in groups or as a whole; any diameter or angle of the reconstructed structures can be easily measured. The Chinese Visible Human male and female data set can provide complete and accurate data. The digitized model of the parapharyngeal space and its surroundings offers unique insights into the complex anatomy of the area, providing morphologic data for imaging diagnosis and surgery of the parapharyngeal space.

Visualization of the temporal bone of the Chinese Visible Human.

Temporal bone anatomy is very difficult to understand. After dataset acquisition of the first Chinese Visible Human, we processed the two-dimensional images to build a digitized visible model of the temporal bone and explore the role of virtual endoscopy in the inner ear. On a SGI workstation three-dimensional computer reconstructions of the ear were generated from the Chinese visible human dataset, viewing the middle and inner ear imitating the traditional otoscopy. The three-dimensional data of the temporal bone were then converted to STL format, and the temporal bone replica were fabricated with rapid prototyping by laminated object manufacturing. The virtual model of the ear was successfully completed, and the virtual endoscopy improved three-dimensional visualization of the middle and inner ear. Physical replica of the temporal bone were built with paper; the accuracy was +/-0.2 mm. The reconstructed model and the replica of the temporal bone can be used to make preoperative plans in the complicated otoneurosurgical operations, allowing various surgical exercises to be carried out on the three-dimensional stereophysical model. The virtual endoscopy stands as a promising new visualization technique for elucidation of the middle and inner ear and reveals a tremendous potential in both clinical and educational settings, providing morphological data for the image diagnosis and otoneurosurgery.