The Effects of Different Adaptive Statistical Iterative Reconstruction-V and Convolution Kernel Parameters on Auto-Segmentation Stability in CT Images / 中国医疗器械杂志

Objective The study aims to investigate the effects of different adaptive statistical iterative reconstruction-V（ ASiR-V） and convolution kernel parameters on stability of CT auto-segmentation which is based on deep learning. Method Twenty patients who have received pelvic radiotherapy were selected and different reconstruction parameters were used to establish CT images dataset. Then structures including three soft tissue organs (bladder, bowelbag, small intestine) and five bone organs (left and right femoral head, left and right femur, pelvic) were segmented automatically by deep learning neural network. Performance was evaluated by dice similarity coefficient（ DSC） and Hausdorff distance, using filter back projection(FBP) as the reference. Results Auto-segmentation of deep learning is greatly affected by ASIR-V, but less affected by convolution kernel, especially in soft tissues. Conclusion The stability of auto-segmentation is affected by parameter selection of reconstruction algorithm. In practical application, it is necessary to find a balance between image quality and segmentation quality, or improve segmentation network to enhance the stability of auto-segmentation.

Feasibility of Evaluating Result of Auto-segmentation of Target Volumes in Radiotherapy with Medical Consideration Index / 中国医疗器械杂志

OBJECTIVE@#To explore the feasibility of using the bidirectional local distance based medical similarity index (MSI) to evaluate automatic segmentation on medical images.@*METHODS@#Taking the intermediate risk clinical target volume for nasopharyngeal carcinoma manually segmented by an experience radiation oncologist as region of interest, using Atlas-based and deep-learning-based methods to obtain automatic segmentation respectively, and calculated multiple MSI and Dice similarity coefficient (DSC) between manual segmentation and automatic segmentation. Then the difference between MSI and DSC was comparatively analyzed.@*RESULTS@#DSC values for Atlas-based and deep-learning-based automatic segmentation were 0.73 and 0.84 respectively. MSI values for them varied between 0.29~0.78 and 0.44~0.91 under different inside-outside-level.@*CONCLUSIONS@#It is feasible to use MSI to evaluate the results of automatic segmentation. By setting the penalty coefficient, it can reflect phenomena such as under-delineation and over-delineation, and improve the sensitivity of medical image contour similarity evaluation.

Application and Development Trend of Medical Image Automatic Segmentation Technology in Radiation Therapy / 中国医疗器械杂志

The development of medical image segmentation technology has been briefly reviewed. The applications of auto-segmentation of organs at risk and target volumes based on Atlas and deep learning in the field of radiotherapy have been introduced in detail, respectively. Then the development direction and product model for general automatic sketching tools or systems based on solid clinical data are discussed.

Using stacked neural network to improve the auto-segmentation accuracy of Graves' ophthalmopathy target volumes for radiotherapy / 生物医学工程学杂志

Compared with the previous automatic segmentation neural network for the target area which considered the target area as an independent area, a stacked neural network which uses the position and shape information of the organs around the target area to regulate the shape and position of the target area through the superposition of multiple networks and fusion of spatial position information to improve the segmentation accuracy on medical images was proposed in this paper. Taking the Graves' ophthalmopathy disease as an example, the left and right radiotherapy target areas were segmented by the stacked neural network based on the fully convolutional neural network. The volume Dice similarity coefficient (DSC) and bidirectional Hausdorff distance (HD) were calculated based on the target area manually drawn by the doctor. Compared with the full convolutional neural network, the stacked neural network segmentation results can increase the volume DSC on the left and right sides by 1.7% and 3.4% respectively, while the two-way HD on the left and right sides decrease by 0.6. The results show that the stacked neural network improves the degree of coincidence between the automatic segmentation result and the doctor's delineation of the target area, while reducing the segmentation error of small areas. The stacked neural network can effectively improve the accuracy of the automatic delineation of the radiotherapy target area of Graves' ophthalmopathy.

Efficacy of repair of bilateral complete cleft lip and nasal deformity by 3dMD face system / 中华医学美学美容杂志

Objective To assess the effectiveness of the Mulliken's method in bilateral complete cleft lip patients with 3dMD system and anthropometric landmarks.Methods Thirty-one infants with bilateral complete cleft lip received treatment in Hospital of Stomatology,Wuhan University between January 2014 and December 2016.Patients underwent primary cheiloplasty and nasoplasty by the same senior surgeon.Periodic review was taken to measure and record the 7 items in the nasolabial area with three-dimensional (3D) images.Results The labial and nasal deformities were restored after primary surgery.The upper lip and nose were corrected and obtained the symmetric shape.The columella was elongated to acquire favorable nasal tip.The arc of nasal fornix was upward.The ridge of the white lipwas continuous and integrated with full vermilion tubercle.Total length of upper lip (Sn-Sto),thickness of the vermilion tubercle (Ls-Sto),protrusion of the nasal tip (Nh) and columellar height (Ch) were markedly improved and there were no significant difference between the observation group and the control group.The significant differences between two groups occurred in values of the nostril width (Nw),which was greater than control group and white lip height (Sn-Ls) and lower than that of control group.Conclusions Mulliken's method during the primary cheiloplasty of the bilateral complete cleft lip shows better results in correction the nasal deformity and the ideal effects are achieved during follow-up.

Clinical treatment of nostril stenosis deformities secondary to bilateral cleft lip nasal correction / 中华医学美学美容杂志

Objective This article reported a patient with severe bilateral nostril stenosis secondary to bilateral cleft lip nasal deformity correction surgery.Methods The surgical procedure included columellar flap and local soft tissue flap was transferred to nasal inside,columellar was narrowed,reconstruction of nasal dome,increased nostrils height and nasal vestibular mucosa area.Results Effective improvement of nasal profile and reduction of ventilation features obstacles was observed.Nasal retainer was used for half a year postoperatively.After two years' follow-up,it showed good results.Conclusions This article is to introduce the therapeutic process and detailed literature review of clinical study of nostril stenosis abnormalities.

Application of septoplasty and primary cheiloplasty for complete unilateral cleft lip / 中华整形外科杂志

Objective@#To explore the application of septoplasty and cheiloplasty in complete unilateral cleft lip repairment, and evaluate the effect on nasal shape correction.@*Methods@#Twenty-four infants with complete unilateral cleft lip were divided into two groups: the correction group and the control group. Both groups underwent cheiloplasty by Mohler′s technique, septoplasty was performed in the correction group during the primary cheiloplasty. Six-month follow-up was taken to evaluate the nasal shape with the three dimensional images. Independent-samples t Test was performed using SPSS 21.0, to compare the nasal morphology between two groups.@*Results@#All patients healed in the first stage, and were followed for 6 months after operations. There were no complication, including nasal septum perforation, occurred in either group.There were statistically significant differences in nasal parameters between the correction group and controls (P<0.05). The columellar width, nostril width on the affected side, and columella deviation of the correction group were smaller, than those of controls. The nose tip height, columellar height and nostril height on the affected side of the correction group were greater than those of the control group.@*Conclusions@#Septoplasty associated with the primary cheiloplasty in complete unilateral cleft lip repairment, shows better results in the elongation of the nasal columella, and the correction of septum deviation, and provides a stable nasal structure.

Application of team approach and key techniques of cleft lip and palate / 华西口腔医学杂志

The development of an expert consensus based on specific domestic situations will provide practical guidance to the efforts aiming at improving cleft care in China. The team approach of twenty-one cleft centers were pooled together, covering pre-surgical orthopedics, primary surgical repair, orthodontic treatment, alveolar bone graft, secondary deformity correction, palatal fistulae repair, the diagnosis and treatment of velopharyngeal incompetence, speech therapy, otitis media management, and skeletal deformity correction. Agreement was achieved among the authors concerning the application of critical surgical and non-surgical techniques. The ambition of this consensus is to introduce more clinicians to the revolution of sequential treatment of clefts, and form the basis for a more comprehensive cleft care manual in the future.

A comparative study on MRI appearance and pathological grading for pancreatic neuroendocrine tumors / 中华内分泌外科杂志

Objective To explore the value of conventional and functional MRI image parameter in preoperative grade of pancreatic neuroendocrine tumours (pNET).Methods Data of 35 cases of pNET were retrospectively analyzed,including tumor size,intensity of T1WI's and T2WI's signal,enhancement feature,and apparent diffusion coefficients (ADC)value.All kinds of tumors were classified into G1 to G3 according to WHO's classification in 2010.Results There were 40 pNETs (mean size(4.2±2.9)cm) among the 35 patients (20 male,and 15 female).By WHO's tumor grading,the number of patients from G1 to G3 was 18(45％),12(30％),and 10(25 ％),respectively.A higher grade was associated with larger tumor size (P＜0.05).Intensity of T1WI and T2WI signal has no significance for predicting tumor grade.Enhancement feature had statistical significance on tumor's grade (P＜0.05).ADC value decreased with the increase of tumor's grade,(2.23±0.80) × 10-3,(1.80±0.73) × 10-3,(0.92±0.24) ×10-3 mm2/s respectively for tumors from grade G1 to G3.Conclusion Enhancement features of MRI image and ADC value are conducive to preoperative grading of pNET.

Imaging features of oblique vaginal septum syndrome and its diagnostic value / 实用放射学杂志

Objective To investigate the imaging findings of oblique vaginal septum syndrome and its diagnostic value.Methods Clinical and radiographic data of 13 patients with oblique vaginal septum syndrome were analyzed retrospectively and relevant literatures were reviewed.All 13 patients underwent ultrasonography examination preoperatively,and 8 of them underwent MRI examination,and 3 patients underwent CT examination as well.The position of the oblique septum,the size of the cavity in the rear of oblique septum, the positional relationship between the cavity in the rear of oblique septum and the cervix,and the concomitant changes of the uterine appendages and urinary system were analyzed.Results The ultrasonography and MRI examinations all manifested as uterus didelphys,cervix duplex,double vagina and obstructed hemivagina,and oblique septum originated from the middle of cervix duplex and attached to one side of the vaginal wall,shielding the ipsilateral cervix;oblique vaginal septum was on the right side in 4 cases and on the left side in 9 cases;the average volume of the cavity in the rear of oblique septum in 6 cases of type Ⅰ was 255 mL,and the average volume in 6 cases of type Ⅱ was 74 mL,and the volume in 1 case of type Ⅲ was 56 mL;2 cases were combined with ipsilateral hematosalpinx and 1 case was combined with a chocolate cyst of ipsilateral ovary;12 cases were accompanied with ipsilateral renal agenesis and 1 case was accompanied with ipsilateral renal hypoplasia.CT examinations of 3 cases all presented as uterus didelphys,a cystic hypodensity lesion under unilateral cervix and ipsilateral renal agenesis.Conclusion Imaging findings of oblique vaginal septum syndrome are quite characteristic. Ultrasonography,CT and MRI examinations have certain value for accurate diagnosis of the disease.

Sodium pyruvate protect occipital cortex of rats with repetitive and severe neonatal hypoglycemia detected by high resolution 1H nuclear magnetic resonance spectroscopy / 中华围产医学杂志

Objectives To investigate the occipital cortex metabolite alterations in repetitive and severe neonatal hypoglycemia rats treated with sodium pyruvate and to reveal the protective role of sodium pyruvate using high resolution 1H nuclear magnetic resonance spectroscopy.Methods Thirty-six 2-dayold Sprague-Dawley rats were randomly divided into hypoglycemia group and pyruvate group with 18 rats in each group.Rats in both groups received intraperitoneal injections of insulin (40 U/kg body weight) at 2,4 and 6 days of age to induce severe hypoglycemia (blood glucose value ≤ 1.4 mmol/L).In the hypoglycemia group,2.5 hours after insulin injection,intraperitoneal injection of 50％ glucose (2 ml/kg) was administered to terminate hypoglycemia,while in the pyruvate group,50％ glucose (2 ml/kg) and sodium pyruvate solution 2.5 ml/kg (500 mg/kg) were injected.Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay was used to observe the status of injured neurons in six neonatal rats,and metabolite changes in occipital cortex of the other 12 rats were detected by 1H nuclear magnetic resonance spectroscopy.The difference between the two groups was compared by independent-samples t test.Results Neonatal rats of both groups reached severe hypoglycemia level 2.5 hours after insulin injection.Compared with hypoglycemia group,pyruvate group had fewer injured neurons (45±5 vs 113 ± 12,t=0.782,P=0.013) and lower injured index in the occipital cortex (0.15 ± 0.03 vs 0.36 ± 0.06,t=l.143,P=0.020).Pyruvate group showed significant decreases in the concentration of taurine [(13.31 ± 2.06) vs (18.44 ± 3.86) mol/kg,t=8.231],glutamine[(1.50 ± 0.24) vs (2.02 ± 0.40) mol/kg,t=3.137],glutamate[(7.04 ± 0.95) vs (9.40 ± 1.73) mol/kg,t=6.449],aspartate[(1.51 ± 0.28) vs (2.15 ± 0.58) mol/kg,t=2.561] and creatine [(6.37±0.99) vs (8.46± 1.77) mol/kg,t =4.226] in the occipital cortex (all P'＜0.017).Conclusions Simultaneous use of glucose and sodium pyruvate to terminate hypoglycemia in repetitive and severe neonatal hypoglycemia rats can effectively alleviate severe hypoglycemia-induced occipital lobe damage via regulating excitatory amino acid neurotransmitters,energy metabolism and other metabolic pathways.

Script-based automated placement of gantry angles for tangential beams of breast cancer / 中华放射医学与防护杂志

Objective To reduce the dose to organ at risk ( OAR) by script-based optimizing the gantry angles of tangential beams for forward-planned intensity-modulated breast radiotherapy ( fIMRT ) plans. Methods A total of 46 patients with breast cancer (26 in left and 20 in right) after conservative surgery who were treated with manually planned fIMRT were retrospectively re-planned using a script to place the tangential beams automatically. The script program was developed using Pinnacle3 scripting language as imbedded in the Pinnacle3 treatment planning system, and the Python scripting language. Dosimetric indices, including V20 of the ipsilateral lung, D1 of the contralateral breast and V10 of the heart were extracted by the script for plans of different gantry angles. Then the optimal tangential angles were selected by a penalty function. Results For the 26 left breast cancer cases, V20 of the ipsilateral lung for manual and script were (18.2 ±3.4)% and (18.1 ±3.4)%, respectively(P>0.05), while D1 of the contra-lateral breast(249. 2 ± 88. 4) cGy and (230. 4 ± 80. 2) cGy, respectively( t=2. 27, P<0. 05), V10 of the heart (13. 7 ± 5. 7)% and (13. 1 ± 5. 7)%(t=2. 82, P<0. 05). The V20 of the ipsilateral lung of the 20 right breast cancer cases were (19. 8 ± 3. 8)% and (19. 8 ± 3. 9)%, respectively(P>0. 05). The script plans achieved better V10 of the heart[(298. 0 ± 239. 7) cGy] than the manual plans[(340. 0 ± 286. 2) cGy] (t =2. 53, P <0. 05). Conclusions Compared with the manualmethod, the script can assess of the impact of tangential beam angles on the OAR dose, patient-specifically and quantitatively, hence make better trade-offs and improve the plan quality.

Script-based automated placement of gantry angles for tangential beams of breast cancer / 中华放射医学与防护杂志

Objective To reduce the dose to organ at risk ( OAR) by script-based optimizing the gantry angles of tangential beams for forward-planned intensity-modulated breast radiotherapy ( fIMRT ) plans. Methods A total of 46 patients with breast cancer (26 in left and 20 in right) after conservative surgery who were treated with manually planned fIMRT were retrospectively re-planned using a script to place the tangential beams automatically. The script program was developed using Pinnacle3 scripting language as imbedded in the Pinnacle3 treatment planning system, and the Python scripting language. Dosimetric indices, including V20 of the ipsilateral lung, D1 of the contralateral breast and V10 of the heart were extracted by the script for plans of different gantry angles. Then the optimal tangential angles were selected by a penalty function. Results For the 26 left breast cancer cases, V20 of the ipsilateral lung for manual and script were (18.2 ±3.4)% and (18.1 ±3.4)%, respectively(P>0.05), while D1 of the contra-lateral breast(249. 2 ± 88. 4) cGy and (230. 4 ± 80. 2) cGy, respectively( t=2. 27, P<0. 05), V10 of the heart (13. 7 ± 5. 7)% and (13. 1 ± 5. 7)%(t=2. 82, P<0. 05). The V20 of the ipsilateral lung of the 20 right breast cancer cases were (19. 8 ± 3. 8)% and (19. 8 ± 3. 9)%, respectively(P>0. 05). The script plans achieved better V10 of the heart[(298. 0 ± 239. 7) cGy] than the manual plans[(340. 0 ± 286. 2) cGy] (t =2. 53, P <0. 05). Conclusions Compared with the manualmethod, the script can assess of the impact of tangential beam angles on the OAR dose, patient-specifically and quantitatively, hence make better trade-offs and improve the plan quality.

Imaging features of oblique vaginal septum syndrome and its diagnostic value / 实用放射学杂志

Objective To investigate the imaging findings of oblique vaginal septum syndrome and its diagnostic value.Methods Clinical and radiographic data of 13 patients with oblique vaginal septum syndrome were analyzed retrospectively and relevant literatures were reviewed.All 13 patients underwent ultrasonography examination preoperatively,and 8 of them underwent MRI examination,and 3 patients underwent CT examination as well.The position of the oblique septum,the size of the cavity in the rear of oblique septum, the positional relationship between the cavity in the rear of oblique septum and the cervix,and the concomitant changes of the uterine appendages and urinary system were analyzed.Results The ultrasonography and MRI examinations all manifested as uterus didelphys,cervix duplex,double vagina and obstructed hemivagina,and oblique septum originated from the middle of cervix duplex and attached to one side of the vaginal wall,shielding the ipsilateral cervix;oblique vaginal septum was on the right side in 4 cases and on the left side in 9 cases;the average volume of the cavity in the rear of oblique septum in 6 cases of type Ⅰ was 255 mL,and the average volume in 6 cases of type Ⅱ was 74 mL,and the volume in 1 case of type Ⅲ was 56 mL;2 cases were combined with ipsilateral hematosalpinx and 1 case was combined with a chocolate cyst of ipsilateral ovary;12 cases were accompanied with ipsilateral renal agenesis and 1 case was accompanied with ipsilateral renal hypoplasia.CT examinations of 3 cases all presented as uterus didelphys,a cystic hypodensity lesion under unilateral cervix and ipsilateral renal agenesis.Conclusion Imaging findings of oblique vaginal septum syndrome are quite characteristic. Ultrasonography,CT and MRI examinations have certain value for accurate diagnosis of the disease.

From microdosimetry to nanodosimetry--the link between radiobiology and radiation physics / 生物医学工程学杂志

The link between micro- and macro-parameters for radiation interactions that take place in living biological systems is described in this paper. Meanwhile recent progress and development in microdosimetry and nanodosimetry are introduced, including the methods to measure and calculate these micro- or nano-parameters. The relationship between radiobiology and physical quantities in microdosimetry and nanodosimetry was presented. Both the current problems on their applications in radiation protection and radiotherapy and the future development direction are proposed.

The specification of parameters driven by measurement data in the construction of virtual sources in Monte Carlo simulation / 生物医学工程学杂志

Dose calculation algorithms based on the Monte Carlo (MC) method are widely regarded as the most accurate tool available in radiotherapy. The MC simulation in radiotherapy has been split into two parts, the radiation source simulation and patient simulation. In this research, a virtual source for simulating the linear accelerator head was constructed with measurement-driven models. The dependence between the calculation accuracy and the specification of various parameters was studied by comparison between the measurement data and calculation results. It has been shown that the dose profile obtained by MC simulation can be consistent with measurement data, suggesting that the compound effect of primary photons and secondary photons are considered with appropriate parameter specification. The requirement of modeling for MC simulation can be met in clinical conditions.

Optimization of the craniospinal radiation technique by synthesizing multiple advanced radiation techniques / 生物医学工程学杂志

Craniospinal radiation is one of essential components in the treatment flow for a number of central nervous system malignancies. Meticulous attention to technique and dosimetry is required to produce optimum tumor control. In this paper, an optimized treatment regimen was proposed based on multiple techniques. The CT images for a 17-year-old male patient in need of craniospinal radiation were acquired for 3D conformal treatment planning. The split-beam technique, the extended penumbra fields matching technique, and the multiple leaf collimator segments and extended SSD technique were synthesized in the treatment regimen so as to work out an optimized treatment plan. The added few segments improved the dose homogeneity in spinal cord. The maximal point dose was decreased from 124% to 108% of the prescribed dose in it. Comparative study on the anthropomorphic phantom showed that the data collected by thermoluminescent detectors and the data obtained by calculation were basically coincident. These results suggest that the proposed technique be clinically acceptable.

Dosimetric analysis on the region of perpendicular electron-photon matching fields / 生物医学工程学杂志

Hot spots and cold spots always appear in the matched region of electron-photon fields. The degree of this kind of dose heterogeneity depends on the physical characteristic of a treatment unit and the energy of electrons. In this paper, a set of dosimetric parameters have been measured on electron rays and x rays for the Elekta Precise treatment unit and the Elekta Synergy treatment unit, respectively. The hot spots and cold spots in the region of perpendicular electron-photon matching fields have been analysed quantitatively. The method to extend penumbra for photon beam profiles was proposed for improving the dose uniformity in the matched regions. And the dose profiles in the matched regions for different treatment units were compared. The results showed that there were stronger hot spots and cold spots for treatment unit with smaller penumbra for photon beams either under the condition of unmodified photon beam profile or the condition of modified photon beam profile.