Objective To explore the applications of im aging exam ination on rib fracture sites in forensic identification. Methods Features including the sites, num bers of the processed im aging exam ination and the first radiological technology at diagnosis in 56 cases of rib fractures from 163 injuries were retro-spectively analyzed. Results The detection rate of the rib fractures within 14 days was 65.6% . The ini-tial detection rate of anterior rib fracture proceeded by X-ray was 76.2%, then 90.5% detected at a sec-ond tim e X-ray, while the detection rate of CTwas 66.7% and 80.0%, respectively. The initial detec-tion rate of rib fracture in axillary section proceeded by X-ray was 27.6%, then 58.6% detected at a second tim e X-ray, while the detection rate of CTwas 54.3% and 80.4%, respectively. The initial de-tection rate of posterior rib fracture proceeded by X-ray was 63.6%, then 81.8% detected at a second tim e X-ray, while the detection rate of CTwas 50.0% and 70.0%, respectively. Conclusion It is im por-tant to pay attention to the use of com bined im aging exam inations and the follow-up results. In the cas-es of suspicious for rib fracture in axillary section, CTexam ination is suggested in such false X-ray negative cases.

Objective To investigate the diagnosis and treatment of primary presacral tumor. Methods The clinical data of 18 patients with primary presacral tumor were retrospectively analyzed. Results Preoperative diagnosis of primary presacral tumor depended on digital rectal examination, endorectal ultrasound, CT, MRI, et al. The surgical approaches of 18 cases included posterior approach (14 cases) and abdominoperineal approach (4 cases). All tumors were completely resected. Postoperative complications were rectal injury (1 case) and wound infection (2 cases), which were cured by symptomatic treatment. Postoperative pathological results showed that 15 cases had benign lesions and 3 cases had malignant lesions. Sixteen patients were followed up from 0.5 to 5.0 years, with recurrence in 2 cases and death in 2 cases. Conclusions Primary presacral tumor should be treated with operation. Sufficient preoperative examination, personalized operative planning, subtle manipulation operative procedures with an experienced multidisciplinary team, are the important points in preventing or reducing recurrence. Endorectal ultrasound plays an important role in the diagnosis and treatment of primary presacral tumor.

Through the study of the pathology of sleep apnea-hypopnea syndrome, evaluation indexes, diagnosis requirements and so on, a portable sleep monitoring system was designed, which had the characteristics of convenience, wireless transmission and no disturbance. The system can be assessed by respiration monitoring and pulse oximetry, which is based on the pressure variation in miniature air-bag and spectral absorption method. It provides the value of the apnea-hypopnea index (AHI), which is used to evaluate OSAHS severity. The experiment of the system's stability and accuracy is done, which exhibits good performance, it can diagnose OSAHS effectively and provide convenience for home monitoring.
Humans ; Oximetry ; Polysomnography ; instrumentation ; Sleep Apnea, Obstructive ; diagnosis

Our country has been using maturity grading method, which was proposed by Grammum in 1979, to evaluate the placental function. However, this method is subjective to consequence because it totally depends on the observation and experiences of clinicians. With the development of ultrasound technology, therefore, we reviewed more novel applications in other aspects of placenta (such as blood flow, vascularization, etc). Over the past years, scholars in the world have done a lot of research around these topics. In this review we introduce placental maturity grading with B-mode ultrasound, placental vascularization qualitative and quantitative analysis with three-dimensional Doppler ultrasound and placental volume measurement, respectively.
Female ; Humans ; Imaging, Three-Dimensional ; Neovascularization, Pathologic ; Placenta ; diagnostic imaging ; Pregnancy ; Ultrasonography, Prenatal

Objective To develop a recognition method of liver steatosis degree on type-B ultrasonic images based on multi-fractal spectrum texture analysis method and pattern recognition. Methods Features of singularity strength width and multi-spectrum area were extracted from the curve of multi-fractal spectrum of each liver ultrasonic images. These two features and the feature of mean intensity ratio comprised a three-dimensional feature vector, which would be classified by BP neural network. Results The classification accuracy was 96.00% for normal liver, 80.00% for mild fatty liver, 88.00% for moderate fatty liver and 92.00% for severe fatty liver. Conclusion Feature vector combined with BP neural network can identify the steatosis degree of liver on the ultrasonic images and can be used as an assistant diagnostic method.

Objective To analyze the stress distribution of abutment and alveolar ridge between two kinds of distal-extention absence dentures,and provide evidence for the application of different dentures in clinic.Methods Attachment denture and cantilever fixed bridge were used to restore the distal-extention absence respectively,the stress distribution of abutment and alveolar ridge was compared by three-dimensioal finit element method.Results The stress peak values of abutmen root,periodontal membrance,alveolar ridge were(1.42E+5)MPa,(1.33E+4)MPa and(3.49E+5)MPa,respectively,in attachment denture;while in cantilever fixed bridge,the stress peak values of them were(1.45E+7)MPa and(2.25E+6) MPa,(1.45E+3)MPa,respectively.And the stress peak values of these two kinds of dentures were all located in the mid-upper 1/3 and the cervical of abutment.Conclusion Compared with cantilever fixed bridge,the attachment denture could decrease the stress of abutment and be helpful to its protection,the hight of residual alveolar ridge should be taken into account when the two kinds of dentures are used for distal-extention absence.

Objective To improve the key steps of direct volume rendering(DVR) method to obtain ideal semitransparent 3D visualization of medical images from 2D slices.Method An arbitrary data set was classified into a simple one and a complex one according to the boundaries existing within the data set,thereby a piecewise linear function was used to construct the transfer function(TF).Low-grayed voxels were regarded as a kind of material which did not radiate but do induce attenuation of sampling lights.The TF was adjusted according to the opacity distribution when one resampling process ends,and the rendering procedure was completed.Result Interior structures of tissues in different levels were rendered.Conclusion Multi-level visualization of 3D medical images for the semitransparent effect can be obtained by considering all the tissues in the data set as semitransparent materials.

Water-fat separation is a particularly important problem for magnetic resonance imaging. Although many methods have been proposed, the reliability is still challenging. In this work, we have presented a method based on the combination of the branch-cut method and multigrid algorithm to get a more robust performance of water-fat separation. First, the branch-cut method is applied to identify residues, which violates the requirement that the interacting phase gradient around a closed path be zero. Residues and branches are marked to be zeros and filled to the weighting factor array. Then, the unwrapped phase array can be given by the multigrid algorithm. Finally, the Dixon method for water-fat separation is applied to the unwrapped phase array. Experiments for brain scanning on the 0.3T low field MRI system demonstrate the successful application of the proposed method.

The methods, present research situation, existing problems, and application foreground of multidimensional reconstruction of ultras onic heart images are discussed in the present paper. According to the procedure of multidimensional reconstruction of ultrasonic heart images, the discussions are presented in respect toimage acquisition, processing, and display. Based on the present situation and existing problems, the future development and applica tion foreground are proposed.

Objective To evaluate the cLinical outcome and influencing factors of open reduction and internal fixation in treatment of hip dislocation combined with acetabular fractures. Methods A retrospective analysis was performed on 51 patients with hip dislocation combined with twetabular frac-tures, who were treated with open reduction and internal fixation under general anesthesia in the emergen-cy department on admission. Of all, 41 patients were treated with open reduction and plate/screw internal fixation, for which the reduction result was evaluated by postoperative X-rays and follow up X-rays accord-ing to Matta's criteria and the functional outcome by Merle d' Aubigne's criteria. Results Of 41 pa-tients, 33 were followed up for 1-7 years (mean 3.1 years). X-ray evaluation showed anatomic reduction in 27 patients (82%), imperfect reduction in five (15%) and poor reduction in one (3%). The clini-cal outcome at the time of final follow-up was graded as excellent in 18 patients (55%), good in 8 (24%), mederate in 3 (9%) and peor in4 (12%), with total excellence rate of 79%. Conclusion Prompt reduction of hip dislocation, precise reduction of the acetabular fracture and decrease of periopera-tive comphcations are key to excellent clinical outcome.