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Objective To evaluate the value of iterative modal reconstruction (IMR) for reducing radiation dose and controlling image quality in cardiac CT. Methods Ten pigs were included. All pigs were scanned on a 256?slice prospectively ECG?gated cardiac CT utilizing routine dose (group A) and tube current reduced by 30%(group B), 50%(group C) and 70%(group D), respectively. Filtered back projection (FBP), hybrid iterative reconstruction (iDose4) and IMR were used for all data, respectively. Image noise and contrast?to?noise ratio (CNR) of ascending aortic root were measured, while overall image quality and coronary artery image quality was rated (five point scale). All results reconstructed by FBP, iDose 4 and IMR were compared. Objective measurements were compared with one?way analysis of variance, and subjective assessments were compared with Kruskal?Wallis H test andχ2 test. Results Compared with that of FBP and iDose4, image noise of IMR was(15.1 ± 6.1),(18.8 ± 5.5),(22.1 ± 4.8)and(33.0 ± 4.0)HU, respectively in group A, B, C and D with significant reduction (F=82.77, 90.71, 96.59, 95.51 respectively, all P0.05) in the diagnosis rates of proximal coronary arteries compared with that using FBP and iDose4, while group C (100%, 40/40) and group D(92%, 37/40) had significantly increased diagnosis rates (χ2=20.05, 45.72, both P<0.01). The diagnosis rates of distal coronary arteries of IMR reconstruction which were 100%(50/50), 98%(49/50), 90%(45/50), 78%(39/50), respectively in groups A, B, C, D had significant increase compared with that of FBP and iDose4 reconstruction (χ2=7.39, 16.75, 34.62, 81.33, all P<0.05). Conclusions IMR can significantly reduce image noise, improve CNR and image quality compared with iDose4. Application of IMR can reduce radiation dose but without compromising image quality.
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Objective To explore the feasibility of using digital imaging processing (DIP)to extract EUS image parameters for the differential diagnosis of autoimmune pancreatitis (AIP)and chronic pancreati-tis (CP).Methods A total of 81 patients with AIP and 100 patients with CP diagnosed from May 2005 to January 2013 were recruited to this study.A total of 105 parameters of 9 categories were extracted from the region of interest by using computer-based techniques.Then the distance between class algorithm and se-quential forward selection (SFS)algorithm were used for a better combination of features.A support vector machine (SVM)predictive model was built,trained,and validated.Results Overall,25 parameters of 5 categories were selected as a better combination of features when the incidence of accurate category was max (90.08%).A total of 181 sample sets were randomly divided into a training set and a testing set by using two different algorithms and 200 random tests were performed.The average accuracy,sensitivity,specificity, the positive and negative predictive values of AIP based on the half-and-half method were (86.04 ± 3.15)%,(83.66 ±6.57)%,(88.54 ±4.37)%,(85.96 ±4.44)% and (87.12 ±4.39)%,respective-ly.Conclusion Computer-aided diagnosis of EUS images is objective and non-invasive,which can improve the accuracy in differentiating AIP from CP.This technology provides a new valuable diagnostic tool for the clinical determination of AIP.
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Objective To extract the texture features of endoscopic ultrasonography (EUS) by digital imaging processing(DIP) and pattern recognition,and then to investigate its value for differential diagnosis between pancreatic cancer and chronic pancreatitis.Methods Two hundred and two patients with pathologicaly confirmed pancreatic malignancy,who underwent EUS from Feb 2005 to Mar 2011,and 104 patients with chronic pancreatitis (including 34 cases of autoimmune pancreatitis),who underwent EUS from May 2002 to Aug 2011,were randomly recruited in this study.The optimal texture features of EUS images in this study were selected by the sequence forward search (SFS) algorithm.With the optimal feature combination,cases were automatically divided into pancreatic cancer and chronic pancreatitis based on the findings of support vector machine (SVM),which were compared with the real results.the sensitivity,specificity,accuracy,positive predictive value and negative predictive value were calculated.Results Nine categories and 105 texture features were extracted based on all EUS images,and 13 features were chosen as optimal combination.Images of 306 cases were randomly divided into training set ( 153 cases,101 cases of cancer,52 cases of chronic pancreatitis) and testing set ( 153 cases,101 cases of cancer,52 cases of chronic pancreatitis).The classifier was trained with the training set and tested with testing set.We proceeded 200 times randomly.the average accuracy,sensitivity,specificity,positive predictive value and negative predictive value were ( 86.08 ± 0.14) ％,(79.47 ± 0.32) ％,( 89.71 ± 0.18 ) ％,( 81.21 ± 0.26 ) ％,( 88.93 ± 0.14 ) ％,respectively.Conclusion Differential diagnosis of pancreatic cancer from chronic pancreatitis by Computer-assisted EUS image analysis,highly accurate,convenient,non-invasive and less costly,is a novel and valuable method of early diagnosis.
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Objective To investigate the methods for localization of the lung segments on three-dimentional (3D) pulmonary perfusion SPECT/CT imaging.Methods Twelve healthy adults were recruited into this study.Lung segments were defined based on the anatomical criteria of CT on transaxial, sagittal and coronal images, including apical, posterior, anterior segments in right upper lobe ( RUL), lateral, medial segments in right middle lobe ( RML), superior, anterior basal, lateral basal, posterior basal segments in right lower lobe (RLL); apical posterior, anterior, superior lingual, inferior lingual segments of left upper lobe ( LUL), superior, medioanterior basal, lateral basal, posterior basal segments of left lower lobe (LLL).Results (1) Eleven typical sections were selected on transaxial SPECT pulmonary perfusion imaging:sternoclavicular joint, supra-arch vessels, aortic arch, azygous arch, right upper lobar bronchus, left upper lobar bronchus, middle lobar or lingual bronchus, basal trunk of bronchus, lower lobar vein, superior and inferior basal vein and basal vein.(2) Twelve typical sections were defined on sagittal imaging:left hilum, bifurcation of left principal bronchus, septa of left pulmonary artery, cardiac apex, the first and second sections left to cardiac apex; right hilum, bifurcation of intermite bronchus, interlobar artery, bifurcation of interlobar artery, the second and third sections right to right atrium.(3) Seven typical sections were defined on coronal imaging:sternoclavicular joint, ascending aorta, bifurcation of pulmonary artery, bifurcation of trachea, intermite bronchus, basal vein and thoracic aorta.Conclusion The developed method was able to localize lung segments on pulmonary perfusion SPECT imaging.
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Objective To process the image of endoscopic uhrasonography(EUS)by digital imaging processing(DIP)and pattem recognition,and to evaluate its efficacy in diagnosis of pancreatic adenocarcinoma.Methods Two hundreds and sixteen patients,who underwent EUS between Feb 2005 and Feb 2007,were randomly recruited to the study.The cohort jncluded 153 cases of pancreatic cancer,which were confirmed by cytological findings after fine-needle aspiration,and 63 cases of non-pancreatic cancer(normal pancreas and chronic panereatitis).The texture features of the EUS image were selected and extracted,and cases were automatically divided into cancer and non-cancer based on findings of support vector machine (SVM).Sensitivity,specificity and accuracy of the technique were calculated.Results From each region of interest(ROI),a total of69 texture features vest in 9 sets were extracted,and 25 features with most set interval were taken as initial.The images of 216 cases were divided randomly into training set(108 eases,76 cancer and 32 non cancer)and testing set(108 cases,77 cancer and 31 non cancer).After 50 times of random tests,the average accuracy,sensitivity and specificity of the diagnosis of pancreatic cancer were (97.98±1.237)%,(94.32±0.0354)%,and(99.45±0.0102)%respectively.Conclusion DIP,combined with computer aided EUS imaging,is an accurate and noninvasive technique in diagnosis of pancreatic cancer.which warrants novel and further researches.
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Objective To evaluate the diagnostic significance of full-field digital mammography (FFDM)for atypieal breast cancer findings.Methods Seven hundred-eighteen cases with breast cancer were examined using FFDM and atypical mammographic findings were found in 134 cases.Craniocaudal (CC)view and mediolateral oblique(MLO)view were conducted for each patient.Mediolateral view or spot view Was achieved if necessary.Preoperative localization Was conducted for the patients with nonpalpable breast cancer8.Results (1)The masses with well.circumscribed margin on mammography were more common in infiltrating duetal carcinoma(22/106),mucinous carcinoma(8/10),medullary carcinoma (5/6),and increased with age and reduction of the mass density.(2)Long spieulation,architectural distortion,patchy high density were mainly found in infiltrating ductal carcinoma and 30-40(24 cases),41-50(34 cases)years old patients.Long speculation wag mainly found in 30-40 years old patients (10/30).(3)Hish homogenous density and subcutaneous edema in the entire breast and mass-like area were most ffequendy found in infiltrating ductal carcinoma at 30-40(2 cases)and 41-50(5 cases)years old.High density and subcutaneous edema were only found in dense breast(8 cases).Conclusion The atypical findings of breast cancer in foil-field digital mammography are associated with the pathological type of cancer.patient age and the gland density of the breast.
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Objective: To evaluate the electron beam computed tomography(EBCT) three-dimensional reconstruction in the diagnosis of bowel obstruction.Methods: Seventy-eight patients suspected of bowel obstruction underwent EBCT with two-phase enhancement scanning and 32 of them were re-established by corona-MPR and sagittal-MPR.All the EBCT results were analyzed and compared with the clinical findings.Results: Seventy-three of the cases were diagnosed as bowel obstruction by EBCT,which were all confirmed by surgery or follow-up,with an accuracy rate of 100% for location diagnosis and 86.3% for etiology.Conclusion: EBCT 3D-reconstruction has great advantages in determining the location,etiology and blood-supply of bowel obstruction.
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Objective To evaluate the value of three-dimensional contrast-enhanced angiography (3D CE MRA) and MRI in the diagnosis and delineation of cerebral arteriovenous malformation(AVM). Methods Twenty-two cases of cerebral AVM examined by MRI and 3D CE,MRA.DSA was performed in 17 cases.A three-dimensional fast low angle shot (3D FLASH) was used for 3D CE MRA with Gd-DTPA dosage of 0.2 mmol per kilogram for body weight.The source images were subtracted from mask images and transferred to computer workstation using three-dimensional reconstruction.Results Among 22 cases, 19 showed typical AVM“flow void”signal on MR images.3D CE MRA clearly displayed the nidus,feeding artery and draining vein.All of the foci were above the cerebellum tentorium.13 located within one lobe, 3 exceeded one lobe and 3 situated in the deep of cerebrum.Feeding arteries were derived from single artery in 9 cases,and mixed supply in 10 cases.Draining veins diverted to sagittal sinus and/or sigmoid sinus in 6,deep cerebral veins in 8 and mixed in 5.In the 14 cases examined by both DSA and 3D CE MRA,3D CE MRA was superior to DSA in three-dimensional demonstration of the nidus,but inferior to DSA in demonstration of some details.3D CE MRA depicted 78.4% feeding arteries and 84.0% draining veins in addition,tiny pathologic blood vessels smaller than 1 centimeter were detected by DSA,but could not be found by 3D CE MRA and were only shown as hemorrhage lesions on MR images in 3 cases.Conclusion As a non-invasive technique,3D CE MRA combined with MRI is accurate in diagnosis and localization of cerebral AVM,and should be used as the first choice for those clinically suspected of AVM.But DSA remains needed for demonstration of details and tiny AVM.
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Objective To assess the clinical value of three dimensional dynamic contrast enhanced MR angiography (3D DCE MRA) in the detection for intracranial aneurysm. Methods 3D DCE MRA was performed in 54 patients highly suspected with intracranial aneurysms. Then conventional digital subtraction angiography (DSA) and feasible endovascular treatment were performed simultaneously. A three dimensional fast imaging with steady state precession (3D FISP) was used for 3D DCE MRA(Gd DTPA dose, 0.2 mmol per kilogram for body weight; acquisition time, 10 seconds). The source images were subtracted from mask images and transferred to computer workstation. All images were subsequently post processed using three dimensional reconstruction. 3D DCE MRA images and DSA images were compared for demonstration of the aneurysm, its neck, and relationship with parent artery, and the usefulness for endovascular treatment was evaluated. Results There were 39 cases with 45 intracranial aneurysms. The sensitivity, specificity, and accuracy of 3D DCE MRA were 96%, 73%, and 90%, respectively. Aneurysm and its neck depiction at 3D DCE MRA was significantly better than that at DSA, especially for aneurysms adjacent to the cavernous sinus and near the PICA of vertebral artery. 3D DCE MRA could guide neurosurgeons to the desired DSA projection, and helped them make plan for interventional or surgical treatment in advance. But the diagnosis should be very carefully made for small aneurysms located in the periphery and the arterial bifurcation. Conclusion 3D DCE MRA is a fast, noninvasive and efficient technique for diagnosing intracranial aneurysms. Its three dimensional information is helpful for DSA demonstration and treatment planning. Any uncertain diagnosis requires DSA confirmation.
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We have recently seen an increasing number of patients with osteoporosis of the type that occurs as a chronic illness in the elderly, and particularly in elderly female patients. It is important not only to treat pain but to follow-up with treatments to prevent further bone mass loss. To measure bone mass in patients with osteoporosis, we employed Digital Imaging Processing (DIP). In this study, the authors examined changes in the bone mass of patients in long-term therapy with Keishi-ka-Jutsubu-to and Gosha-Jinki-Gan. As a comparative-control group, or non-treatment group, we selected 11 patients who had been diagnosed as having osteporosis in an outpatient clinic, and whose bone mass had been measured with DIP. These patients discontinued treatment, but returned to the outpatient clinic six months to one year later. The average duration of non-treatment in the control group was 9.8 months. Metacarpal index (MCI) and metacarpal bone mineral density (m-BMD) at the first visit were 0.40±0.07 and 2.22±0.38, but 10 months later they were 0.36±0.05 and 1.97±0.38, which represents a significant decrease.<br>In 20 cases given Keishi-ka-Jutsubu-to, the initial bone mass data were: MCI, 0.39±0.08; m-BMD, 2.07±0.32. Measurements performed after three, six, and nine months of treatment showed no difference or increase from the initial values.<br>In 12 cases given Gosha-Jinki-Gan, the initial data were: MCI, 0.40±0.07; m-BMD, 2.06±0.27. Measurements performed after three, six and nine months of treatment showed no difference from the initial values.<br>The severity of pain was equally reduced by treatment with Kampo formulation or NSAIDs (non-steroidal anti-inflammatory drugs) by four weeks, but after eight weeks low back pain in patients treated with the Kampo formulation was significantly reduced compared with low back pain in the group treated with NSAIDs.
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Objective To summarize the quality control method of the SOLO CR system running in high efficient-reliable-stablestatus and to obtain the high quality digital imaging.Methods In order to keep the system operating normally,we make the detail plan ofquality control in combination with practical status such as working status and frequency of use,and implement properly maintenance andrepairing for 3 AGFA ADC SOLO CR.Results To ensure the 3 CR system operating normally and steadily,and achieve good results asexpected in 2 years.Conclusion The suitable and effective quality control is necessary.It provides the reliable ensuring for outputting high quality digital imaging.