The image guided radio therapy (IGRT) Imaging System based on cone-beam computer tomography (CBCT) can reach the goal of improving the accuracy of the radiotherapy. However, because the clinical registration between CBCT images and Planning CT images is carried out manually, it inevitably reduces radiation positioning accuracy to some extent. To tackle the problem, we proposed a new feature vector selection method for the CBCT image elastic registration in the framework of hierarchical attribute matching mechanism for elastic registration (HAMMER) algorithm. We analyzed the characteristics of HAMMER algorithm and used Canny operator which has a better edge detection and positioning performance to replace the noise-sensitive gradient amplitude. Therefore, we used a new attribute vector, which consisted of the intensity, Laplacian of the Gaussian and Canny operator, to ex tract the image feature points in CBCT and planning CT images. We also presented an adaptive feature-point selection method and the choice criteria of attribute vector weights. Experimental results showed that the new feature vector effectively avoided the noise interference resulted from scattering lines in CBCT images to improve registration accuracy, and it also decreased the required feature point numbers and reduced the computation redundancy, so that it provided a new approach for the clinical elastic registration of CBCT and Planning CT rapidly and accurately.
Algorithms ; Cone-Beam Computed Tomography ; Humans ; Radiotherapy ; methods ; Radiotherapy Planning, Computer-Assisted

BACKGROUND:Previous studies from Shaanxi Institute of Ophthalmology have shown that ostrich cornea has the advantages to be developed into the alternatives of human corneal material.
OBJECTIVE:To determine the potential toxic effects of ostrich corneal stromal scaffold on cel s.
METHODS:Cel culture methods were used to culture L-929 cel s in the extracts of ostrich acel ular corneal
stroma which was dried and dehydrated. 3-(4,5)-Dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazoliumromide assay was used to evaluate the growth and proliferation of cel s after cultured for 1, 2 and 3 days.
RESULTS AND CONCLUSION:After the cel s were cultured in the extracts of ostrich acel ular corneal stroma subjected to dryness and dehydration for 1, 3 and 5 days, and the toxicity level of cultured cel s was graded as level 1. The cytotoxicity test was conducted according to the“National Standard of the People's Republic of China GB/T16886.5-2003”. After cultured in the extracts of ostrich acel ular corneal stroma, a smal number of cel s were round in shape and loosely adherent without intracytoplasmic granules, and cel lysis could be observed
occasional y. The results of 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazoliumromide assay showed that
the ostrich acel ular corneal stromal scaffold which was dried and dehydrated had level 1 of cytotoxicity and could be considered as a qualified material.

Objective Using Eclipse and Pinnacle3 V 7.4f treatment planning sytems (TPS) for dose calculation of the CT images of simulation phantom,patients and homogeneous organization phantom,to compare the differences between the two TPS for the calculation of non-uniform organizations.Methods For the CT images of simulation phantom,patients and homogeneous organization phantom,the calculating results between the two TPS were compared,including the common used clinical indexes of V20 and V30 of the lung,D95 of the planning target volume,the doses of the ISO and eight points of interest inside ISO slice.Resuits For simulation phantom and patients,although the calculating differences of the isocenter doses between the two TPS were small,the differences of other indicators were large.For example,when using secondary collimator irradiation,the maximal D95 difference of planning target volume reached 10.17%for patients and 4.64%for simulation phantom.When using muhileaf collimator irradiation,the maximal D95 difference reached 10.74%for patients and 5.66%for simulation phantom.Sometimes the dose differences of points 1-4 at the edge of planning target volume were more than 10%.In addition,the V30 differences of the lung were large too.But for the homogeneous organization phantom,the calculating differences were small.Conclusions The calculating differences between the two TPS are less for simulation phantom than for patients,and more for simulation phantom and patients than for homogeneous organization phantom.

Objective To assess the feasibility for the automated treatment planning verification system Mobius3D (M3D) to perform an independent 3D dose calculation in intensity-modulated radiotherapy (IMRT) for cervical cancer.Methods Twenty patients with cervical cancer were randomly selected.With treatment planning systems (Pinnacle,Version 9.2;Eclipse,Version 13.5),all IMRT plans were divided into 7 fields to meet the dosimetric goals.The optimized plans were exported to the M3D server.The percentage differences in the volume of region of interest (ROI) and the dose calculation of target volume and organ at risk (OAR) were evaluated for the two treatment planning systems,and theγ passing rate was used to assess the accuracy of M3D calculation.Results The difference in the volume of ROI for Pinnacle 9.2 to M3D was less than that for Eclipse 13.5 to M3D,with maximum differences of 0.22％±0.69％ and 3.5％±1.89％ for Pinnacle 9.2 and Eclipse 13.5,respectively.The differences in the dose calculation of target volume and OAR for the two treatment planning systems to M3D were within ± 1％.After recalculating by M3D,the dose difference between Pinnacle 9.2 and M3D was smaller than that between Eclipse 13.5 and M3D,but the mean differences were all within ±3％.The γ passing rates for target volume and OAR were more than 95％ on average.Conclusions The method of utilizing the automated treatment planning verification system to validate the accuracy of plans is convenient.It can be used as a secondary check tool to improve accuracy in IMRT dose calculation.

ObjectiveTo study the efficacy of using multileaf collimators with different position and different degree in the treatment of nasopharyngeal carcinoma (NPC) using intensity-modulated radiotherapy techniques.Methods Ten patients withNPC were administered andanalyzed.Thepenumbra characteristics, dose of target, and radiation conformal indexes (CI) of mode T1 and mode T2 were measured and compared using dose volume histogram generated by Varian Eclipse three-dimensional planning computer system. Mode T1 :The angles of seven coplanar beams were 0°, 52°, 106°, 160°, 212°, 258°and 308°,respectively. There were no restriction on the position and degree of multileaf collimators. Parameters were set and optimized. Mode T2 :The beam angles and the parameters were as same as mode T1. According to the actual situations, the position and the degree of the multileaf collimators were changed. Then thedose optimization was performed. Results Target dose coverage in both mode T1 and T2 could be clinically accepted, and the CI were 0. 82 and 0. 83(t = -0. 25, P =0. 815). The maximum dose reductions in the lens, eyes, optic nerves and corneas were 28. 7% (t = 4. 80, P = 0. 000), 2. 7% (t = 2. 99, P = 0. 021),1.4%(t= 1.05,P=0.032), and 30.5% (t=2.99,P=0. 020), respectively. However, the mean dose and V35 of the parotid were increased by 0. 6% (t = - 2. 82, P = 0. 043) and 9.9% (t = - 2. 05, P =0. 038). ConclusionsOpimization of multileaf collimators can reduce the scattering and leaking rays. Compared with mode T1 ,controlling the position and degree of multileaf collimators could reduce the radiation dose to the eyes and optic-nerves, especially to the lens.

OBJECTIVE: To summarize clinical experience of application of argon knife under electronic bronchoscope in the management of pediatric glottic and subglottic diseases. METHOD: Reports in the literature were reviewed. Outcome and prognosis of 4 cases with pediatric glottic and subglottic diseases managed with argon beam coagulator technique in Shanghai children's Medical Center since 2011 were retrospectively analyzed. RESULT: Granulation tissue hyperplasia in 3 cases with subglottic lesions did not recur after surgery. Scarring or stenosis were not found in the airway. Intubation of the trachea and tube of tracheotomy was pulled out successfully in all cases, restoring normal breathing. No lesion recurrence was found in 1 case with squamous cell moderate atypical hyperplasia one month after the surgery. CONCLUSION Electronic bronchoscope has advantages of clear image, fine and soft lens body, optional bending, angle conversion, accurate positioning. And the argon knife with small head diameter can pass the pediatric supraglottic. It can be manipulated precisely with short operation time and no damage to surrounding normal tissues. Its worth in popularization and application of management for with glottic and subglottie disease in pediatric patients.
Adolescent ; Argon ; therapeutic use ; Bronchoscopes ; Child ; China ; Cicatrix ; Humans ; Hyperplasia ; Intubation, Intratracheal ; methods ; Laryngeal Diseases ; surgery ; Lasers, Gas ; therapeutic use ; Neoplasm Recurrence, Local ; Prognosis ; Retrospective Studies ; Tracheotomy ; instrumentation

A complex disease is rarely a consequence of abnormality in a single gene. It is known that many drugs exhibit a therapeutic effect by acting on multiple targets, produce synergies to intervene the occurrence and development of diseases. Unlike the traditional methods which act on single molecule or pathway, this disease-drug target network constructed with high throughput data vividly showed the complex relationship between drugs, their targets and diseases. However, the networks are usually extremely complex. In order to reduce the complexity, it is necessary to deconstruct the network and identify module structures. In this study, framework of module analysis was summarized from four aspects: module concept, structure and identification methods, importance of disease-drug module identification, and its application. Module-based analysis provides a new perspective for deciphering the drug intervention mechanisms for complex diseases, and provides new ideas and pathways to reveal the mechanisms of multi-target and multi-component drugs.
Drug Delivery Systems ; Drugs, Chinese Herbal ; administration & dosage ; chemistry ; Gene Regulatory Networks ; drug effects ; Humans ; Molecular Targeted Therapy

Objective To evaluate the position deviation of multi-leaf collimator (MLC) in volumetric modulated arc therapy for nasopharyngeal carcinoma and to verify a method of detecting the leaf position accuracy.Methods Thirty-two volumetric modulated arc plans of nasopharyngeal carcinoma were randomly selected.A clockwise arc with a gantry range of 181° to 179° and a counterclockwise arc with a gantry range of 179° to 181° were uscd for each plan.Each arc contained two leaf groups,groups A and B.By using the Argus software,the actual MLC leaf positions were extracted from the Dynalog files in the Varian Trilogy accelerator.The planed MLC leaf positions were compared with the actual positions,and the differences were calculated between them.Results The proportions of the leaf position errors within ± 2,± 1.5,± 1 and ± 0.5 mm were 99.99％,99.90％,99.07％ and 93.98％,respectively.The proportions of the leaf position errors within ± 1 mm were 98.08％,100％,98.97％ and 99.01％ for the first therapeutic arc (ARC1),second therapeutic arc (ARC2),A and B groups,respectively.The leaf position errors range of ARC1 and ARC2 were-2.95 to 2.99 and-0.22 to 0.23 mm (t =2.35,P ＜ 0.01).The leaf position errors range of leaf bank A and leaf bank B were-2.95 to 2.68 and-2.92 to 2.99 mm(P ＞ 0.05).Conclusions During the volumetric modulated arc radiotherapy,the leaf positions deviation are in control.The Dynalog files can be used as an effective way to analysis the leafposition errors.

ObjectiveTo investigate the dosimetric difference in the application of RapidArc using 6 and 15 MV X-rays for radiotherapy of multiple hepatic malignancy.MethodsA total of 12 cases with multiple hepatic tumors ( primary 5 cases and secondary 7 cases) were selected.All patients underwent the three dimensional CT simulation in free breathing.For each patient,RapidArc plans with single or two 358° arcs using 6 or 15 MV X-rays were designed respectively,the prescription dose was 2Gy per fraction × 25 fractions.The dosimetric differences were compared among RapidArc plans.ResultsAll of RapidArc plans could meet the clinicalrequirement.There were no significant differences in the conformity index ( CI ),homogeneity index ( HI),the maximum dose and the minimum dose of PTV among RapidArc plans ( P ＞ 0.05).All the CI could get to 0.91 and HI could get to 0.88.In the RapidArc plans with two 358° arcs,the Vs,V10,V15 of normal liver were higher than with single arc,while V20,V25,V30,V35,V40 were lower than with single arc.There were no significant differences in the different radiation dose of normal liver,stomach,duodenum and spinal cord among different plans ( P ＞0.05 ).The monitor units of RapidArc plans using 6 MV X-rays increased 12％ compared to 15 MV averagely.CondusionThe 6 MV X-ray would be selected chiefly in the radiotherapy of multiple haptic tumor using RapidArc with whole arc(s).

Background Ostrich acellular corneal stroma possesses a similar constitution to human corneal stroma,so it is expected to become one of ideal biological corneal carriers.Objective This study was to investigate the immunogenicity of acellular stroma carrier of ostrich cornea and offer the information for the development of industrialization and clinical use of acellular stroma carrier of ostrich cornea.Methods Twenty fresh ostrich eyeballs and 20 porcine eyeballs were collected.Acellular corneal stroma carriers of ostriches and pigs were prepared using low temperature freezing joint enzyme digestion method and desiccant dehydration method and sterilized by cobalt-60 irradiation.The corneal stroma carriers were preserved using drying and dehydration method.Forty-five male BALB/c mice were randomly divided into the sham operation group,ostrich acellular corneal stroma group and porcine acellular corneal stroma group.Acellular corneal stroma carriers of ostriches and pigs(wet weight after rewatering was 10 mg/piece) were subcutaneously implanted to the back of BALB/c mice,respectively.Wound healing and inflammatory response on the operative site were observed,and phenotype and activating rate of CD4+,CD8+ and CD25+in peripheral blood of mice were dynamically detected 7,14 and 28 days after ectopically implantation of heterogeneous corneal stroma by immunofluorescence labeling and flow cytometry analysis.Results No swelling and exudation were seen in the skin of operative site of the mice with a good healing of wound after surgery.There were no significant differences in the activating rates of CD4+,CD8+ and CD25+ cells in the peripheral blood of mice among the sham operation group,the porcine acellular corneal stroma group and ostrich acellular corneal stroma group in the three time points after surgery(CD4+:F=0.74,P=0.50;F=0.39,P=0.05;F=3.46,P=0.58.CD8+:F=1.75,P=0.21 ;F=1.14,P=0.35;F=0.78,P=0.48.CD25+:F=0.52,P=0.61 ;F=3.53,P=0.62;F=2.42,P=0.13).Conclusions The ostrich acellular heterogeneous corneal stroma carrier possesses low immunogenicity.It is inferred that ostrich acellular corneal stroma carrier can be used in heterogeneous corneal transplantation.