Objective To study the effect of iterative algorithm (iDose algorithm) on image quality and radiation dose in paranasal sinus MSCT.Methods A proper cadaveric head based on the average CNR (contrast noise ratio) of paranasal sinus images in 53 patients was applied.The cadaveric head was scanned with different parameters of kV and effective mAs.The images were reconstructed with filtered back projection and iterative algorithm (iDose 1-7) respectively.The subjective and objective evaluations were performed for all the images and the optimal parameter combination was found out.Results The CNR of coronal images was slightly higher than that of axial images (t =-6.86,P ＜0.05).The image CNR of protocol (120 kV,100 mAs/slice and iDose5) was close to that of conventional protocol.The protocol of 100 kV,60 mAs/slice and iDose4 offered the images adaptable for diagnosis of inflammation.The protocol of 100 kV,80 mAs/slice and iDose4 offered the images adaptable for diagnosis of inflammation and fracture,and the radiation dose were reduced by 82％ and 75％,respectively.Conclusions Using the iDose algorithm could help to offer diagnostic images for inflammation and fracture and reduce the radiation dose in the paranasal sinus MSCT.

Objective The objective of this article was to compare patients' dose with electrocardiographic gated mA modulation (ECG) and ECG＆CAREDose 4D mode during coronary MSCT angiography.Methods The research was based on phantom experiment and computer simulation to get the mean value of peak skin dose data and effective dose data respectively and to analyze deterministic and stochastic radiation risk.Results The peak skin dose using ECG mode alone and using ECG＆CAREDose 4D mode with the same image noise level was (87.4±0.9) and (45.9 ± 1.2) mGy respectively.Effective dose was 17 and 10 mSy for ECG mode and ECG＆CAREDose 4D mode respectively.Comparing with ECG mode alone, ECG＆CAREDose 4D mode reduced organ dose of gonad, red marrow, lung, stomach, breast and thyroid by 40.0%, 36.7%, 39.3%, 37.7%, 38.8% and 38.9%, respectively. Conclusion Results showed that ECG ＆ CAREDose 4D mode can reduce radiation dose effectively comparing using ECG mode alone, and that ECG ＆ CAREDose 4D mode should be widely applied ehnically with appropriate initial settings.

The paper is aimed to provide a novel index, named as multidimensional spatial triangular area, for the evaluation of the release-absorption correlation of multiple component traditional Chinese medicines (TCMs). The applicability of the method was demonstrated by the example data. The method and standard practice for evaluation of the release-absorption correlation for western medicines with single compound could not be applied to TCMs with multiple components. The release percentage or absorption percentage of the multiple components for TCMs at the sampling time was a point in the multidimensional space. The area of the triangle formed byt the sequential three points rrepresented the changing characteristics of the components' release and absorption kinetics. The side lengths of the triangle could be calculated from the spatial distances between each two of the sequential three points. Then the triangle area could be obtained by the side lengths. The in vitro release-in vivo absorption correlation of the multiple components could be represented by the correlation between the integrating values of the release triangle areas and that of the absorption triangle areas. The results of the examples indicated that the multidimensional spatial triangular area method could treat the multiple components in a holistic way, in line with the holism the hi he TCMs. Therefore, the multidimensional spatial triangular area method provided new methodology for the release-absorption correlation of the TCMs with multiple components.

Objective To study the impact on the radiation dose,organ doses of eye lens and thyroid and image quality with different scanning modes in head and neck CT scan.Methods The simulation phantom of head and neck was scanned by using fixed scanning condition (120 kV and 200 mAs),as well as the combinations of automatic tube current modulation (CARE Dose 4D),automatic tube voltage modulation technique (CARE kV) and partial angle scanning mode (X-CARE) respectively.Six kinds of scanning modes were adopted,including 120 kV +200 mAs,120 kV + 200 mAs + X-CARE,CARE Dose 4D + 120 kV,CARE Dose 4D + 120 kV + X-CARE,CARE Dose 4D + CARE kV,CARE Dose 4D + CARE kV + X-CARE.Two thermolumineseece dosimeters (TLDs) were exposed at the skin surface positions of eye lens and thyroid,and the values measured with two TLDs were averaged.The CT dose index volume (CTDIvol) and dose length product (DLP) for every scan were recorded,and the contrast to noise ratio (CNR) in eye lens section and thyroid section were measured.Results The crgan doses of lens and thyroid were 19.8 and 26 mGy at 120 kV and 200 mAs,as well as 13.3 and 22.2 mGv at X-CARE mode.Compared with the manual selection of 120 kV,the combination of CARE kV and CARE Dose 4D made the values of CTDIvol drop from 13.1 to 10.1 mGy,the doses of eye lens and thyroid from 16.6 and 20.8 mGy to 23.7 and 19.9 mGy respectively,while the image quality reducedsignificantly.Compared with CARE Dose 4D + 120 kV,the organ doses of eye lens and thyroid were reduced from 20.8 and 23.7 mGy to 9.6 and 15.1 mGy for with additional X-CARE,while CTDIvol dropped from 13.1 to 9.3 mGy.When the combination of CARE Dose 4D + CARE kV + X-CARE was used,CTDIvol and organ doses were reduced to a minimum,when the CNRs of head and neck were also minimized.Conclusions The scanning mode CARE Dose 4D + 120 kV + X-CARE for head and CARE Dose 4D + CARE kV for neck can effectively reduce the radiation dose while keeping good image quality.When requirements for image quality are not high,CARE Dose 4D + CARE kV + X-CARE mode can be selected to reduce the radiation dose significantly.

Objective To explore the influence on image quality and the reduction of radiation dose to eye lens when using bismuth shielding in sinus MDCT.Methods The standard water phantom was scanned using clinical scanning protocols of sinus in 16-MDCT,and the images were acquired with none,1 layer,2 layers and 3 layers of bismuth shielding severally.Using the above protocol,the cadaveric head was scanned with no shield,1,2 and 3 layers of bismuth shielding material covered on both eyes,and the organ dose to eye lens in each scanning was measured with thermoluminescence dosimeter (TLD).The sponge with the thick of 0.5,1.0,1.5,2.0 cm was placed between the shielding material and the surface of subjects separately and the radiation doses to eye lens was measured with sinus scanning conditions in the same way.The CT values of phantom with the distances of 2.0,4.0,6.0 and 8.0 cm to shield material were measured.The influence of bismuth artifacts on anatomic structures was evaluated as well.Results The organ doses to the eye lens in the sinus clinical CT were 20.0 mGy.Doses decreased significantly to 13.7,10.9 and 9.4 mGy separately when using 3 types of bismuth shielding thickness.With different thicknesses of shielding material,the greater the shield gap,the smaller the degree of reduction of organ dose,but the increasment of CT value was significantly reduced.Using 1-layer shield no gap and 2-layer shield with 1.5 cm gap in sinus MDCT,the radiation doses were reduced to 13.7 and 13.1 mGy with the reduction rates of 31.5％ and 34.5％ respectively.Conclusion The reasonable bismuth shielding can effectively reduce the radiation dose to eye lens in sinus CT on the premise of ensuring image-diagnostic quality.

Objective To explore the effects on image quality and dose reduction to the lens when using bismuth shielding in head and neck MSCT.Methods The standard phantom and the cadaveric head with none,1,2 and 3 layers of bismuth shielding were scanned with protocols of brain,temporal bone and paranasal sinuses using a 16-MDCT scanner.The organ dose to the lens in each scanning was measured with thermoluminescence dosimeters(TLD).The above scanning with sinus protocol was repeated with a sponge with thickness of 5,10,15 and 20 mm placed between the shielding and phantom/head.The CT attenuation of phantom with the distance of 2,4,6 and 8 cm to shielding were measured.The image quality was subjectively evaluated by 2 physicians.Results The organ doses of the lens with protocols of brain,temporal bone and sinuses were 24.31,27.60 and 20.01 mGy,respectively.The doses were decreased significantly when using bismuth shielding.With the increase of the shield gap,the degree of dose reduction was reduced,but the increasing degree of CT attenuation significantly reduced.Using 2-layer and 3-layer bismuth shield in brain and temporal bone CT scan,the radiation doses were reduced by 47.1％ and 59.1％,respectively while maintaining the diagnostic image quality.Using 1-layer shield without gap and 2-layer shield with 1.5 cm gap in sinus CT,the radiation doses were reduced by 31.5％ and 34.5％,respectively.Conclusions Reasonable usage of bismuth shielding can effectively reduce the radiation dose to the lens of eye in head and neck MSCT.

Objective To investigate the diagnosis and treatment characteristics of pure red cell aplasia (PRCA)caused by human parvovirus (HPV)B19 infection after renal transplantation.Methods Two cases with PRCA caused by HPV B19-induced after renal transplantation,who were treated in the Department of Organ Transplantation,Nanfang Hospital,Southern Medical University,were summarized.Combined with literature review,the clinical characteristics,diagnostic method,course of treatment and prognosis of such disease were investigated.Results Two renal transplant recipients developed severe anemia early after transplantation with progressive deterioration and failed transfusion therapy.Other causes of anemia were ruled out and two patients were diagnosed as PRCA caused by HPV B19 infection according to bone marrow aspiration and biopsy as well as HPV DNA detection by fluorescent polymerase chain reaction (PCR).The symptoms of anemia were improved significantly after adjustment of immunosuppressive treatment protocol and intravenous immunoglobulin (IVIG).Conclusions For patients with unexplained and progressed anemia early after renal transplantation,especially those complicated with reticulocyte deficiency,the possibility of PRCA caused by HPV B19 infection shall be considered.The results of bone marrow aspiration and fluorescent PCR are the main bases for diagnosing PRCA.Immunosuppressive agents reduction and application of IVIG are the major treatment measures.Most of patients have great prognosis after treatment,but this disease is likely to recur.

Objective:To explore the effect of damage control surgery on polytraumatism with severe oral maxillo-facial trauma.Methods: We retrospectively analyzed 32 cases of polytraumatism with severe oral maxillo-facial trauma treated by damage control surgery.Results: The principles of damage control surgery were successfully applied to the treatment.Of the 32 cases,31 survived,with their polytraumatism sequentially managed,and only 1 died.Conclusion: Damage control surgery helps to raise the success rate in the treatment of polytraumatism with severe oral maxillo-facial trauma.

Objective Parotidectomy and superficial parotidectomy are traditional surgical treatment to the malignant parotid gland tumour although they have many defects.The aim of this study was to analyze the feasibility of individualized treatment to patient according to tumor`s size and TNM stage. Methods Thirty three patients with low grade malignant parotid gland tumours from Dec 2005 to Dec 2010 were recruited in the present study.All the patients received the territorial surgical resection firstly.Then, 9 cases re-ceived the expanded territorial surgical resection (1 case had recurrent probability, accepted adjuvant radiotherapy).Sixteen cases un-derwent parotidectomy with complete tumor resection ( 2 case had envelope invasion, accepted adjuvant radiotherapy) .Eight cases ac-cepted adjuvant radiotherapy(4 cases on T1 and T2 stage preserved facial nerve although the nerves adhering to tumors, and other 4 ca-ses on T4a stage accepted facial nerve excision ) . Results Follow up ranged from 3.5 to 8.5 years and no recurrences were docu-mented.9 patients who accepted territorial surgical resection showed fine facial symmetry.8 cases of them without adjuvant radiotherapy had good salivary secretion.Nine cases of other 24 patients showed temporary facial nerve injury and recovered within 1 to 4 months. Four cases with facial nerve excision showed permanental facial paralysis. Conclusion To protect the function of parotid gland to the greatest extent, the small low grade malignant parotid gland tumors without facial nerve invasion could have territorial surgical resection. Combined territorial surgical resection with postoperative adjuvant radiation therapy is useful to avoid the tumors recurrence and en-croachment of facial nerve to protect the facial nerve function.

Objective Carotid body tumor is closely related to carotid artery .How to deal with carotid artery is the guaranty of successful surgery .The aim of this study was to summary the experience of keeping carotid artery continuity in the treatment of 15 carotid body tumor cases . Methods Clinical data of 15 cases with 17 carotid body tumors , in which 2 patients had bilateral tumors , were collected.The 17 carotid body tumors were classified as Shamblin I (6 cases),Ⅱ(6 cases) andⅢ(5 cases).Fifteen tumors were dissected simplely.Among these 15 tumors, three of Shamblin Ⅱand two of Shamblin Ⅲunderwent repair of the break of carotid artery.The rest two of Shamblin Ⅲunderwent tumor and external carotid artery excision and internal carotid artery repairment .Matas pressing test of carotid artery or carotid artery balloon occlusion test was not performed in any patient . Results All 17 tumors were successfully excised .None of the 17 tumors underwent anastomosis or reconstruction of internal carotid artery or arteria carotis com -mun.The continuity of carotid artery or internal carotid artery was kept in all the patients after tumor excision .Hoarseness and bucking induced by the injury of vagus nerve occurred in 13 cases, and bucking recovery in all the cases after 2 years follow up, and only one case remained mild hoarseness .Hypoglossal nerve injury occurred in 4 cases with tongue deviation , and the symptom recovery after 6 months follow up.No one had recurrent by the follow-up period ranging from 1 to 9 years. Conclusion Most carotid body tumors could be completely resected by tumor dissection method with the accurate treatment , thereby the continuity of carotid artery could be kept.The Matas pressing test of carotid artery or carotid artery balloon occlusion test is not necessarily to every patient .