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In recent years, artificial intelligence (AI) has developed rapidly in the field of medical imaging. However, the collaborations among hospitals, research institutes and enterprises are insufficient at the present, and there are various issues in technological transformation and value landing of products in this area. To solve the core problems in the developmental path of medical imaging AI, the Chinese Innovative Alliance of Industry, Education, Research and Application of Artificial Intelligence for Medical Imaging compiled the . This article introduces the current status of collaboration, the clinical demands for medical imaging AI technique, and the key points in AI technology transformation: robustness, usability and security. We are facing challenges of lacking industry standards, data desensitization standard, assessment system, as well as corresponding regulations and policies to realize the application values of AI products in medical imaging. Further development of AI in medical imaging requires breakthroughs of the core algorithm, deep involvement of doctors, input from capitals, patience from societies, and most importantly, the resolutions from government for multiple difficulties in links of landing the technology.
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<p><b>OBJECTIVE</b>To investigate the blood supply of primary lung cancer (PLC) using CT angiography for bronchial artery (BA) and pulmonary artery (PA).</p><p><b>METHODS</b>Thin-section enhanced multi-layer spiral CT (MSCT) were carried out in 147 primary lung cancer patients and 46 healthy subjects as control. Three-dimensional images of bronchial artery and pulmonary artery were obtained using volume render (VR) and multi-planar reconstruction (MPR) or maximum intensity projection (MIP) at the workstation, and their morphological findings and relationship with the mass were assessed.</p><p><b>RESULTS</b>136 primary lung cancer patients and 32 healthy controls were evaluated for at least one bronchial artery displayed clearly in VR. The detective rate of the bronchial artery was 92.5% and 69.6%, respectively. The bronchial artery caliber and the total section area of lesion side in lung cancer patients were significantly larger than that on the contralateral side and that of the control (P < 0.05). Bronchial artery on the lesion side in lung cancer was dilated and tortuous, directly penetrating into the mass with reticularly anastomosed branches. In the PLC patients, all PA were shown clearly with normal morphological image though crossing over the masses in 54 patients; In 25 PLC patients, the PA being essentially intact, was pushed around and surrounded the mass, giving the "hold ball" sign; In 40 other PLC patients, PA being also intact, the mass surrounded and buried the PA from the outside, crushing the PA flat resulting in an eccentric or centrifugal shrinkage, forming the "dead branch" sign; In the rest 28 patients, the PA was surrounded and even compressed, forming the "residual root" sign.</p><p><b>CONCLUSION</b>Primary lung cancer patient shows dilated bronchial arteries and increased bronchial artery blood flow, whereas pulmonary arteries just pass through the mass or are compressed by the mass. It is further demonstrated that the bronchial artery, instead of the pulmonary artery, is the main vessel of blood supply to the primary lung cancer as shown by MSCT angiography of bronchial artery and pulmonary artery.</p>
Subject(s)
Female , Humans , Male , Middle Aged , Adenocarcinoma , Diagnostic Imaging , Angiography , Methods , Bronchial Arteries , Diagnostic Imaging , Carcinoma, Squamous Cell , Diagnostic Imaging , Lung Neoplasms , Diagnostic Imaging , Pulmonary Artery , Diagnostic Imaging , Tomography, Spiral Computed , MethodsABSTRACT
Objective:To optimize the injection protocol of contrast medium for contrast-enhanced MRA (CEMRA) of pulmonary artery and to evaluate the diagnostic value of CEMRA and pulmonary perfusion imaging (PPI) in an experimental model of acute pulmonary embolism. Methods:CEMRA and PPI were performed in 6 normal pigs with different doses of gadolinium contrast agent (5ml, 10ml, 15ml, 20ml and 25ml) at an injection rate of 3ml/s, and 3 pulmonary embolism models were injected with 20 ml contrast agent at 3 ml/s. DSA was also performed for comparison. Results:The signal intensities and the signal to noise ratios of the pulmonary arteries kept increasing with the dose increase of the contrast agent, but the best angio-pulmonary contrast dose was 10-15ml (0.25-0.375mmol/kg), while the optimal dose for PPI was 15-20ml (0.375-0.5mmol/kg). Although CEMRA demonstrated less obstructed pulmonary arteries than DSA (5/10 vs 8/10)did, it detected all obstructions when combined with PPI. The pulmonary infarction zones showed wedge-shaped perfusion defects on the PPI images, with the signal intensities lower than those of the normal areas (137.86±45.32 vs 330.14±46.52, P<0.001). Conclusion:It is suggested that the optimal dose of the contrast agent is 0.25mmol/kg to 0.375mmol/kg for CEMRA, and 0.375mmol/kg to 0.5mmol/kg for lung perfusion. CEMRA combined with PPI may be better than DSA in demonstrating pulmonary embolism.
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Objective:To optimize the injection protocol of contrast medium for contrast-enhanced MRA (CEMRA) of pulmonary artery and to evaluate the diagnostic value of CEMRA and pulmonary perfusion imaging (PPI) in an experimental model of acute pulmonary embolism. Methods:CEMRA and PPI were performed in 6 normal pigs with different doses of gadolinium contrast agent (5ml, 10ml, 15ml, 20ml and 25ml) at an injection rate of 3ml/s, and 3 pulmonary embolism models were injected with 20 ml contrast agent at 3 ml/s. DSA was also performed for comparison. Results:The signal intensities and the signal to noise ratios of the pulmonary arteries kept increasing with the dose increase of the contrast agent, but the best angio-pulmonary contrast dose was 10-15ml (0.25-0.375mmol/kg), while the optimal dose for PPI was 15-20ml (0.375-0.5mmol/kg). Although CEMRA demonstrated less obstructed pulmonary arteries than DSA (5/10 vs 8/10)did, it detected all obstructions when combined with PPI. The pulmonary infarction zones showed wedge-shaped perfusion defects on the PPI images, with the signal intensities lower than those of the normal areas (137.86±45.32 vs 330.14±46.52, P<0.001). Conclusion:It is suggested that the optimal dose of the contrast agent is 0.25mmol/kg to 0.375mmol/kg for CEMRA, and 0.375mmol/kg to 0.5mmol/kg for lung perfusion. CEMRA combined with PPI may be better than DSA in demonstrating pulmonary embolism.
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Objective To investigate the value of functional MRI in the diagnosis and differential diagnosis of breast diseases.Methods Sixty-five patients with 68 lesions were enrolled in this study. Conventional T_1 WI and T_2 WI scan,dynamic contrast enhanced MRI,diffusion weighted imaging and ~1H single voxel MR spectroscopy were performed consequently.All lesions were verified by pathology,including 4 cases of breast adenosis,22 fibroadenomas,2 chronic inflammations,3 cysts,33 infitrating ductal carcinomas,1 intraductal carcinoma and 3 cystosarcoma phyllodes tumors.Morphological features,maximum enhancement ratio,time-intensity curve,apparent diffusion coefficient and Choline peak were analyzed. Results The detection rates of T_1 WI and T_2 WI were 14.7%(n=10)and 51.5%(n=35).The sensitivity,specificity,accuracy of dynamic contrast.enhanced MRI for the malignant tumor were 94.6%, 71.4% and 76.5% respectively.Retrospective study showed that diffusion weighted imaging,with the b value from 800 s/mm~2 to 1000 s/mm~2,could be used to differentiate various types of breast lesions.~1H signal voxel spectroscopy had a sensitivity of 51.4%,specificity of 82.6%,and accuracy of 67.6% for the malignent.The sensitivity,specificity and accuracy could reach 97.3%,90.0% and 92.6% respectively by combining conventional scan,dynamic contrast enhanced MRI and MR spectroscopy.Conclusion Functional MRI,with high sensitivity,specificity and accuracy,can be used widely in the diagnosis of malignant breast lesions.
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Objective To assess the clinical application of contrast-enhanced MR angiography using three-dimensional(3D)time-resolved imaging of contrast kinetics(CE-MRA 3D-TRICKS).Methods TRICKS is a high temporal resolution(2—6s)MR angiographic technique using a short TR(2.8— 4.0 ms)and TE(0.9—1.3 ms),partial echo sampling and the central part of the k-space being updated more frequently than the peripheral part of the k-space.Pre-contrast mask 3D images are first acquired and 15--20 sequential 3D images following bolus injection of Gd-DTPA are then acquired.Results Thirty patients underwent contrast-enhanced MR angiography using TRICKS.Twelve vertebral arteries were well displayed on TRICKS.Seven of them showed normal,bilateral vertebral artery stenosis was shown in 1 case, and unilateral vertebral artery stenosis was shown in 4 wth aecompaning ipsilateral carotid artery bifurcation stenosis in one case.Bilateral renal artery showed normal in 4 cases,and the artery in transplanted kidney showed normal in one case and stenosis in another case.The cerebral artery showed normal in 2 cases, sagittal sinus thrombosis was detected in one case and intracranial arteriovenous malformation in one case. Pulmonary artery displayed normal in 3 cases,pulmonary artery thrombosis was seen in one case and pulmonary sequestration's abnormal feeding artery and draining vein was revealed in one case.The feeding artery in left lower limb fibrolipoma was showed in one case.The radial-ulnar artery artificial fistula stenosis was seen in one case,and left antebrachium hemangioma was showed in one case.Conclusion TRICKS can clearly delineate the whole body vascular system and can reveal any vascular abnormality.It is convenient and with high successful rate,which make it the first method of choice in displaying vascular abnormality.