OBJECTIVE: To establish a cone beam computed tomography (ECBCT) system for high-resolution imaging of the extremities. METHODS: Based on three-dimensional X-Ray CT imaging and high-resolution flat plate detector technique, we constructed a physical model and a geometric model for ECBCT imaging, optimized the geometric calibration and image reconstruction methods, and established the scanner system. In the experiments, the pencil vase phantom, image quality (IQ) phantom and a swine feet were scanned using this imaging system to evaluate its effectiveness and stability. RESULTS: On the reconstructed image of the pencil vase phantom, the edges were well preserved with geometric calibrated parameters and no aliasing artifacts were observed. The reconstructed images of the IQ phantom showed a uniform distribution of the CT number, and the noise power spectra were stable in multiple scanning under the same condition. The reconstructed images of the swine feet had clearly displayed the bones with a good resolution. CONCLUSIONS The ECBCT system can be used for highresolution imaging of the extremities to provide important imaging information to assist in the diagnosis of bone diseases.
Algorithms ; Animals ; Artifacts ; Calibration ; Cone-Beam Computed Tomography ; instrumentation ; methods ; Equipment Design ; Extremities ; diagnostic imaging ; Image Processing, Computer-Assisted ; methods ; Phantoms, Imaging ; Radiographic Image Enhancement ; instrumentation ; methods ; Swine

To explore the safety and efficacy for radiofrequency ablation of paroxysmal supraventricular tachycardia (PSVT) guided by Carto Univu three-dimensional mapping system.
 Methods: A total of 99 patients with PSVT underwent radiofrequency catheter ablation (RFCA) were assigned to a Carto Univu group (51 patients) and a two-dimensional X-ray group (48 patients) according to the mapping method. The operation time, X-ray exposure time, X-ray exposure dose, dose area product (DAP), operation success rate and complication rate were compared between the two groups.
 Results: The Carto Univu group and the two-dimensional X-ray group were not significant difference in the operation time, the X-ray exposure time of placing catheter, the X-ray DAP of placing catheter, the number of discharge, the discharge power, and the total discharge time (P>0.05). The mapping and ablation time, total exposure time, mapping and ablation DAP and total DAP in the Carto Univu group were significantly lower than those in the two-dimensional X-ray group (P<0.01). In the right accessory pathway cases, the mapping and ablation DAP and the total DAP in the Carto Univu group decreased compared with X-ray group (P<0.05), but it decreased more profound (P<0.01) in the left accessory pathway cases and the dual atrioventricular nodal pathways cases. Seven cases in the Carto Univu group achieved "zero X-ray", including 5 cases of the dual atrioventricular nodal pathways and 2 cases of the left accessory pathway. The immediate success rate for the two groups was 100%. After 3-12 months of follow-up, there was no recurrence in the Carto Univu group but 3 suspected recurrences in the two-dimensional X-ray group. In addition, no complications occurred in the two groups. 
 Conclusion: Carto Univu electroanatomic mapping system can guide PSVT safely and effectively during radiofrequency ablation and reduce radiation exposure to both doctors and patients. It is especially suitable for dual atrioventricular nodal pathways, which may even achieve "zero X-ray". Perhaps Carto Univu will be the first choice for RFCA of dual atrioventricular nodal pathways.
Catheter Ablation ; instrumentation ; methods ; Humans ; Imaging, Three-Dimensional ; instrumentation ; methods ; Operative Time ; Radiation Exposure ; prevention & control ; statistics & numerical data ; Radiography ; statistics & numerical data ; Recurrence ; Tachycardia, Supraventricular ; diagnostic imaging ; surgery ; Treatment Outcome

OBJECTIVES: An animal experiment clarified that insertion of an orthodontic apparatus activated the trigeminal neurons of the medulla oblongata. Orthodontic tooth movement is known to be associated with the sympathetic nervous system and controlled by the nucleus of the hypothalamus. However, the transmission of both has not been demonstrated in humans. The purpose of this study were to examine the activated cerebral areas using brain functional magnetic resonance imaging (MRI), when orthodontic tooth separators were inserted, and to confirm the possibility of the transmission route from the medulla oblongata to the hypothalamus. METHODS: Two types of alternative orthodontic tooth separators (brass contact gauge and floss) were inserted into the right upper premolars of 10 healthy volunteers. Brain functional T2*-weighted images and anatomical T1-weighted images were taken. RESULTS: The blood oxygenation level dependent (BOLD) signals following insertion of a brass contact gauge and floss significantly increased in the somatosensory association cortex and hypothalamic area. CONCLUSION Our findings suggest the possibility of a transmission route from the medulla oblongata to the hypothalamus.
Brain Mapping ; methods ; Healthy Volunteers ; Humans ; Hypothalamus ; diagnostic imaging ; Magnetic Resonance Imaging ; methods ; Medulla Oblongata ; diagnostic imaging ; Tooth Movement Techniques ; instrumentation

OBJECTIVES: To develop a measurement software of lung compression degree to calculate the lung compression ratio in pneumothorax patients accurately and quickly, and then provide an objective assessment of damage degree in forensic clinical identification. METHODS: A volume calculation software was established according to the working principle of the CT instrument. CT data of 15 pneumothorax patients were selected as research objects. The lung compression ratio of pneumothorax patient was calculated by the lung compression volume calculation software of the CT instrument. Meanwhile, the lung compression ratio was also calculated by the developed volume calculation software. The lung compression ratio and operation time calculated by the two methods were analyzed statistically. Scatter plot graphs were draw based on related data, and the developed volume calculation software was verified. RESULTS: The difference between the lung compression ratios calculated by the two methods was not statistically significant, but showed a linear correlation （P<0.05）. The operation time of the developed volume calculation software was obviously shorter. CONCLUSIONS The volume calculation software developed in this study can calculate the lung compression degree of pneumothorax more conveniently and rapidly with easy accessibility, which shows an application value in the forensic practice.
Forensic Medicine/instrumentation* ; Humans ; Image Processing, Computer-Assisted/methods* ; Lung/diagnostic imaging* ; Pneumothorax ; Software ; Tomography, X-Ray Computed

OBJECTIVETo investigate the preoperative assessment value of spectral CT quantitative parameters in lymph node metastasis of gastric cancer.

METHODSFrom December 2013 to June 2015, clinical and image data of 86 patients with gastric cancer confirmed by gastroscope pathology undergoing preoperative enhanced CT were prospectively collected. Enhanced CT included nonenhanced CT of conventional 120 kVp mode, arterial phase (AP) and venous phase (VP) with GSI mode on Discover GSI CT scanner. The raw data were transferred to ADW4.6 workstation to reconstruct the monochromatic images at 70 keV and iodine-based images in AP and VP with 1.25 mm thickness. The short diameter, long diameter, ratio of short to long diameter, CT attenuation and iodine value of lymph nodes in each phase were measured and recorded. Pathology results were used as golden standard. The spectral CT quantitative parameters of positive and negative lymph nodes were compared by t test and the sensitivity and specificity analyses were performed by ROC curves. This clinical study registration number 81271573.

RESULTSAmong these 86 gastric cancer patients (53 male and 33 female), tumors of 28 cases were in upper part, of 12 cases in middle part, of 27 cases in distal part and of 19 cases involved two parts. Thirty-five cases were differentiated type and 51 cases were undifferentiated type. A total of 1 072 lymph nodes were found in operation, of which 412 nodes were positive and 660 were negative. Among 552 lymph nodes found in CT images, 338 nodes were positive and 214 were negative. Compared to negative lymph nodes, short diameter [(9.52±3.58) mm vs. (6.48±2.94) mm, t=4.639, P=0.000], ratio of short to long diameter (0.82±0.14 vs. 0.61±0.08, t=13.514, P=0.000), CT attenuation in precontrast [(20.44±6.77) Hu vs. (16.06±7.14) Hu, t=3.154, P=0.002], CT attenuation in AP[(61.71±11.78) Hu vs. (40.11±10.18) Hu, t=9.588, P=0.000], CT attenuation in VP[(71.34±13.03) Hu vs. (53.81±11.39) Hu, t=7.888, P=0.000], iodine value in AP [(16.17±4.22) 100 μg/cmvs. (8.03±3.10) 100 μg/cm, t=9.781, P=0.000], the iodine value in VP [(20.13±6.04) 100 μg/cmvs. (11.58±4.13) 100 μg/cm, t=10.147, P=0.000] of positive lymph nodes were greater. The long diameter was not significantly different between positive and negative lymph nodes [(11.71±5.63) mm vs. (10.64±3.20) mm, t=1.380, P=0.169]. The area under ROC curve of short diameter, ratio of short to long diameter, CT attenuation in precontrast, AP and VP, iodine value in AP and VP of lymph nodes was 0.600, 0.880, 0.648, 0.832, 0.755, 0.864, 0.835, respectively. Taking the ratio of short to long diameter over 0.72 as diagnosis standard, the sensitivity was 75.6% and the specificity was 93.5%. Taking the CT number in AP over 49.75 Hu, the sensitivity was 66.9% and the specificity was 88.8%. Taking the CT number in VP over 59.80 Hu, the sensitivity was 69.9% and the specificity was 77.6%. Taking the iodine value in AP over 9.65 (100 μg/cm), the sensitivity was 80.4% and the specificity was 82.2%. Taking the iodine value in VP over 15.65 (100 μg/cm), the sensitivity was 69.9% and the specificity was 86.9%. Combinong the ratio of short to long diameter with the iodine value in AP, the sensitivity was 95.2% and the specificity was 76.9%.

CONCLUSIONSThe ratio of short to long diameter, the iodine value and CT attenuation in AP and VP of lymph nodes in spectral CT are important criteria to evaluate the metastasis of gastric cancer. Combining the ratio of short to long diameter with the iodine value in AP can obviously improve the sensitivity.

Female ; Gastroscopy ; Humans ; Iodine Radioisotopes ; Lymph Nodes ; diagnostic imaging ; pathology ; Lymphatic Metastasis ; diagnostic imaging ; Male ; ROC Curve ; Sensitivity and Specificity ; Stomach Neoplasms ; diagnostic imaging ; Tomography, X-Ray Computed ; instrumentation ; methods

OBJECTIVETo assess the clinical value of the diagnostic laparoscopy in choosing treatment strategies for patients with gastric cancer.

METHODSRetrospective analysis was performed on clinical and pathological data collected from 2 023 patients undergoing gastric cancer surgery in the Zhongshan Hospital of Fudan University from 2009 to 2014. All the patients were diagnosed as gastric cancer by endoscopic biopsy and staged by imaging examination before surgery. During the diagnostic laparoscopy procedure, a small periumbilical incision was made and a pneumoperitoneum with COunder 10-15 mmHg was established through a port. A 10 mm trocar was put in, and the camera was inserted. Two 5 mm trocars were put in two ports which located in midclavicular line two fingers under the left and right costal margin and then the instruments were inserted. A thorough inspection included ascites, the abdominal cavity, liver, diaphragm, spleen, greater omentum, colon, small intestine, mesentery, adnexa (female) and pelvic floor. If the tumor located at the posterior part of the stomach, the gastrocolic ligament was opened in order to look for carcinomatosis in the omental bursa. The accuracy rate of diagnostic laparoscopy in diagnosing adjacent organ invasion and intra-abdominal metastasis was calculated, and the rate of adjusting treatment plans after diagnostic laparoscopy was also calculated.

RESULTSThere were 52.7%(1 067/2 023) of patients underwent diagnostic laparoscopy. The accuracy rate of diagnostic laparoscopy in evaluating adjacent organ invasion and intra-abdominal metastasis were 98.3%(1 049/1 067) and 98.1%(1 047/1 067) respectively. Besides, 14 patients with stage T4b and 32 with intra-abdominal metastasis, which were missed by imaging examination, were diagnosed by diagnostic laparoscopy. The treatment plans of 9.3% (99/1 067) of patients were changed after diagnostic laparoscopy, and 65 (6.1%) cases of non-therapeutic laparotomy were avoided. However, 18 cases of adjacent organ invasion and 20 cases of intra-abdominal metastasis were still missed by diagnostic laparoscopy, and 12 cases received non-therapeutic laparotomy.

CONCLUSIONDiagnostic laparoscopy has considerable value in assessing adjacent organ invasion and intra-abdominal metastasis and has great clinical significance in making precise treatment plans.

Abdominal Neoplasms ; diagnostic imaging ; secondary ; Digestive System ; pathology ; Digestive System Surgical Procedures ; methods ; Female ; Humans ; Laparoscopes ; Laparoscopy ; instrumentation ; methods ; statistics & numerical data ; Laparotomy ; statistics & numerical data ; Male ; Neoplasm Invasiveness ; diagnostic imaging ; Patient Care Planning ; statistics & numerical data ; Retrospective Studies ; Stomach Neoplasms ; diagnostic imaging ; surgery ; Surgical Instruments ; Unnecessary Procedures ; statistics & numerical data

Endoscopy plays an important role in the diagnosis and treatment of postoperative complications of gastric cancer. Endoscopic intervention can avoid the second operation and has attracted wide attention. Early gastric anastomotic bleeding after gastrectomy is the most common. With the development of technology, emergency endoscopy and endoscopic hemostasis provide a new treatment approach. According to the specific circumstances, endoscopists can choose metal clamp to stop bleeding, electrocoagulation hemostasis, local injection of epinephrine or sclerotherapy agents, and spraying specific hemostatic agents. Anastomotic fistula is a serious postoperative complication. In addition to endoscopically placing the small intestine nutrition tube for early enteral nutrition support treatment, endoscopic treatment, including stent, metal clip, OTSC, and Over-stitch suture system, can be chosen to close fistula. For anastomotic obstruction or stricture, endoscopic balloon or probe expansion and stent placement can be chosen. For esophageal anastomotic intractable obstruction after gastroesophageal surgery, radial incision of obstruction by the hook knife or IT knife, a new method named ERI, is a good choice. Bile leakage caused by bile duct injury can be treated by placing the stent or nasal bile duct. In addition, endoscopic methods are widely used as follows: abdominal abscess can be treated by the direct intervention under endoscopy; adhesive ileus can be treated by placing the catheter under the guidance of endoscopy to attract pressure; alkaline reflux gastritis can be rapidly diagnosed by endoscopy; gastric outlet obstruction mainly caused by cancer recurrence can be relieved by metal stent placement and the combination of endoscopy and X-ray can increase success rate; pyloric dysfunction and spasm caused by the vagus nerve injury during proximal gastrectomy can be treated by endoscopic pyloromyotomy, a new method named G-POEM, and the short-term outcomes are significant. Endoscopic submucosal dissection (ESD) allows complete resection of residual gastric precancerous lesions, however it should be performed by the experienced endoscopists.
Anastomosis, Surgical ; adverse effects ; Bile Ducts ; injuries ; Constriction, Pathologic ; etiology ; therapy ; Digestive System Fistula ; etiology ; therapy ; Duodenogastric Reflux ; diagnostic imaging ; etiology ; Endoscopy, Gastrointestinal ; methods ; Enteral Nutrition ; instrumentation ; methods ; Female ; Gastrectomy ; adverse effects ; Gastric Outlet Obstruction ; surgery ; Gastritis ; diagnosis ; Gastrointestinal Hemorrhage ; etiology ; therapy ; Hemostasis, Endoscopic ; methods ; Hemostatics ; administration & dosage ; therapeutic use ; Humans ; Male ; Neoplasm Recurrence, Local ; surgery ; Postoperative Complications ; diagnosis ; therapy ; Precancerous Conditions ; surgery ; Pylorus ; innervation ; physiopathology ; surgery ; Stents ; Stomach Neoplasms ; complications ; surgery ; Treatment Outcome ; Vagus Nerve Injuries ; etiology ; surgery

Rectal cancer is one of the common cancers which poses a threat to the health of mankind. In recent years. Multi-modality treatment strategies for locally advanced rectal cancer improve the treatment efficiency. Accurate prediction of the treatment response after the neoadjuvant chemoradiotherapy (CRT) can guide more suitable treatment strategy. MERCURY study proved the prognostic value of post-CRT standard morphologic MRI(T2-weighted) assessment of tumor regression grade(TRG), and MRI assessment of circumferential resection margin can guide the definitive surgery. Compared with standard morphologic MRI (T2-weighted), functional MRI, including diffusion weighted imaging (DWI) and dynamic contrast enhanced (DCE) MRI, has shown more promising results for the prediction of therapeutic response in rectal cancer. The addition of diffusion-weighted images to T2-weighted images improves the accuracy of restaging examinations for determination of complete pathologic responders. DCE can reflect the tumor micro-vascular environment, and the change of perfusion in response to treatment. These images have the potential to improve the accuracy of therapeutic response in rectal cancer.
Chemoradiotherapy ; statistics & numerical data ; Contrast Media ; Diffusion Magnetic Resonance Imaging ; statistics & numerical data ; Humans ; Magnetic Resonance Imaging ; methods ; statistics & numerical data ; Margins of Excision ; Neoadjuvant Therapy ; statistics & numerical data ; Neoplasm Staging ; instrumentation ; methods ; statistics & numerical data ; Prognosis ; Rectal Neoplasms ; blood supply ; diagnostic imaging ; pathology

To evaluate the efficacy and safety of drug-eluding beads transarterial chemoembolization (DEB-TACE) in treatment of unrecectable hepatocellular carcinoma (HCC).The clinical data of 42 consecutive HCC patients undergoing TACE were retrospectively analyzed, including 20 cases received conventional TACE (cTACE group) and 22 cases received TACE with epirubicine-loaded microspheres (CalliSpheres) (DEB-TACE group). MRI scans were performed 1 week before and 1, 3 and 6 months after initial therapy. The response to treatment, disease recurrence, complications and adverse effects were documented and compared between two groups.There were no significant differences in 1-month, 3-month and 6-month objective response rate (CR+PR) and disease control rate (CR+PR+SD), disease recurrence, complications and adverse effects of interventional therapy between cTACE group and DEB-TACE group. Additionally, there were no significant differences about locoregional biliary injuries, intrahepatic biloma, and newly detected intra- or extrahepatic HCC on MRI between cTACE group and DEB-TACE group.There were no statistically significant differences between cTACE group and DEB-TACE group with regard to the short-term response, disease recurrence, complications and side effects. Hepatic-locoregional complications may be more frequent in DEB-TACE group than those in cTACE group.
Carcinoma, Hepatocellular ; diagnostic imaging ; therapy ; Chemoembolization, Therapeutic ; adverse effects ; instrumentation ; methods ; Comparative Effectiveness Research ; Drug Delivery Systems ; instrumentation ; methods ; Epirubicin ; administration & dosage ; therapeutic use ; Humans ; Liver Neoplasms ; Magnetic Resonance Imaging ; Microspheres ; Neoplasm Recurrence, Local ; Retrospective Studies ; Treatment Outcome

The advent of three-dimensional printing (3DP) technology has enabled the creation of a tangible and complex 3D object that goes beyond a simple 3D-shaded visualization on a flat monitor. Since the early 2000s, 3DP machines have been used only in hard tissue applications. Recently developed multi-materials for 3DP have been used extensively for a variety of medical applications, such as personalized surgical planning and guidance, customized implants, biomedical research, and preclinical education. In this review article, we discuss the 3D reconstruction process, touching on medical imaging, and various 3DP systems applicable to medicine. In addition, the 3DP medical applications using multi-materials are introduced, as well as our recent results.
Biomedical Research ; Computer-Aided Design ; Diagnostic Imaging/*instrumentation/*methods ; Humans ; Precision Medicine ; *Printing, Three-Dimensional ; Prostheses and Implants