Objective
To clarify the thin-layer 16-slice spiral CT features of coal worker’s pneumoconiosis and the superior distribution of comorbidities in their staging and lobes and lung field anatomy.
Methods
Sixty-six patients with coal worker's pneumoconiosis diagnosed by the pneumoconiosis diagnosis and identification group from October 2014 to March 2015 were enrolled. All patients underwent 16-slice spiral CT and thin-layer CT reconstruction with a thickness of 1.5 mm. The thin-slice CT signs and comorbidities of coal workers’ pneumoconiosis were observed, and the superior distribution of CT signs in patients at different stage and different lobes and lung field anatomy were evaluated.
Results
There were 16 cases of irregular small nodules in the lungs, 22 cases of large shadow fusion, 18 cases of intraocular shadow calcification, 41 cases of emphysema, 21 cases of pulmonary bullae, 21 cases of pulmonary hypertension, and 31 cases of enlarged lymph nodes in the mediastinum and calcified. The above signs were mostly distributed in stage Ⅲ pneumoconiosis (P<0.05). There were 32 cases of regular small nodules, which were mostly distributed in stage Ⅰ pneumoconiosis. In the 16 cases of irregular small nodules, the advantage was distributed in the middle and outer lobes of the double lungs. In the 22 cases of large shadow fusion, the advantage was distributed in the upper and lower lobe of the lungs. In the 16 cases of tuberculosis, the advantage was distributed in the upper lobe of the lungs. In the 21 cases of bullous bullae, the advantage was distributed in the upper lobe of the two lungs, mostly in the right upper lung.
Conclusion
The thin 16-slice spiral CT signs of coal worker’s pneumoconiosis can reflect the pathological changes, and have a certain correlation with the stage of pneumoconiosis, and have obvious characteristics in the anatomical distribution of lung and lung fields.
【Abstract】ObjectiveBy using multidetectorrow spiral CT (MDCT), to investigate the CT imaging features of inflammatory diseases in retroperitoneal space with correlation of radiological anatomy.MethodsThe clinical and laboratory dada of 30 patients with proven inflammatory diseases of retroperitoneal space were collected. All patients underwent MDCT plain scanning and portal venous acquisition. CT imaging data generated at portal venous phase were processed with coronal, sagittal and oblique multiplanar reformation (MPR) technique.ResultsAcute pancreatitis and various types of renal infection were the two main sources of retroperitoneal inflammation. Depending on the specific anatomic locations, retroperitoneal inflammation of different subspaces demonstrated characteristic imaging features. Spreading of inflammatory process across subspaces was also quite common.ConclusionMDCT is the imaging method of choice to depict comprehensively and clearly the inflammatory diseases of various retroperitoneal spaces.
Objective To assess value and limitations of non-invasive methods in assessing liver fibrosis．Methods By summarized current situation and advancement of serum fibrotic markers, ultrasound, CT and MRI in assessing liver fibrosis, we investigated their value and limitations. Results In addition to diagnosis, non-invasive methods of assessing liver fibrosis assess severity of liver fibrosis. For liver fibrosis, however, non-invasive methods can not monitor effectively reaction to therapy and progression. Conclusion Non-invasive methods play important roles in diagnosis and assessing severity of liver fibrosis, and reduce the need of liver biopsy.
ObjectiveTo explore the clinical value of dual-source CT perfusion imaging (CTPI) in the assessment of cerebral hemodynamic changes in patients with internal carotid atherosclerosis.
MethodsThirty patients diagnosed to have internal carotid atherosclerosis by CT angiography examination with various degrees of stenosis or occlusion were treated between January 2012 and May 2013. Whole brain perfusion imaging was performed on all the patients. We rebuilt the CTPI figure parameters respectively, including cerebral blood volume (CBV), blood flow (CBF), mean transit time (MTT) and time to peak (TTP) to assess brain tissue perfusion.
ResultsIn the 30 patients with internal carotid atherosclerosis, 8 had mild stenosis lumen, 12 moderate stenosis, 7 severe stenosis and 3 had occlusion. In mild stenosis cases, TTP of stenosis-side vessels was higher than those of coutralateral side (P<0.05), and there were no significant differences in other perfusion parameters between bilateral vessels among mild stenosis cases (P>0.05). MTT and TTP of stenosis-side vessels were higher than those of contralateral side in moderate stenosis cases (P<0.05). In severe stenosis or obstruction cases, MTT and TTP of stenosis-side vessels were higher than those of contralateral side, while CBF and CBV of stenosis-side vessels were lower than contralateral side (P<0.05). Twenty-two in the 30 cases had perfusion abnormalities, and there was a significant difference between the stenosis side cerebral perfusion and the healthy side mirror area (P<0.05).
ConclusionCTPI can reflect brain tissue perfusion early and comprehensively, and fully reflect internal carotid atherosclerosis caused by severe stenosis or occlusion of cerebral hemodynamic changes, which provides important information for clinical treatment and helps clinicians to formulate individualized treatment plan.
Objective To investigate multi-slice spiral CT (MSCT) and MRI features of stasis cirrhosis and the diagnostic value of MSCT and MRI. Methods MSCT and MRI findings of 35 patients with stasis cirrhosis were studied. The size of liver and spleen, the diameter of hepatic vein (HV), enhancement pattern of liver parenchyma, contrast medium reflux in inferior vena cava (IVC) and (or) HV, ascites, number of varices and correlated abnormalities were reviewed. Results The volume index of liver and spleen of 35 patients was 4434.95 cm3 and 621.92 cm3 respectively. The mean diameter of HV of 27 patients (77.1%) was 3.61 cm and HV of other 8 patients (22.9%) were too small to show. Number of patients showed waves of borderline, inhomogeneous pattern of parenchymal contrast enhancement, contrast medium reflux in IVC and (or) HV, varices and ascites was 5 (14.3%), 29 (82.9%), 20 (57.1%), 16 (45.7%), and 6 (17.1%), respectively. Correlated abnormalities included cardiac enlargement 〔4 cases (11.4%)〕, pericardium thickening 〔11 cases (31.4%)〕, and pericardial effusion 〔2 cases (5.7%)〕. Conclusions Stasis cirrhosis mainly demonstrate liver enlargement, inhomogeneous pattern of parenchymal contrast enhancement, contrast medium reflux in IVC and (or) HV, and slight portal hypertension. MSCT and MRI play invaluable roles in diagnosis, differential diagnosis and etiological diagnosis of stasis cirrhosis.
ObjectiveTo analyze the CT features of parotid tuberculosis, in order to increase the cognition and diagnostic level of the disease.
MethodsNine cases of parotid tuberculosis confirmed by pathology and laboratory examinations between August 2009 and December 2012 were collected retrospectively, and we analyzed their CT features which were then compared with pathological findings.
ResultsAll the 9 cases involved unilateral parotid, among which 7 were on the left side and 2 on the right side. Eight cases were parotid lymph node tuberculosis located in parotid superficial lobe, including 3 cases of single lesion and 5 cases of multiple lesions. There were 30 lesions in total with diameters ranging from 0.5 cm to 4.5 cm, presenting slightly lower density on CT scan. Twenty-five lesions were moderate homogeneous enhancement; four lesions were ring-like enhancement; and one lesion was lace-like enhancement. Six cases of parotid lymph node tuberculosis had thickened platysma, and subcutaneous fat and skin were at different levels. Six cases in the group were accompanied with enlargement of cervical lymph nodes. One case of parotid gland essence tuberculosis involved its superficial and deep lobe diffusely presenting heterogeneous slightly low density, in which we could see some patchy low density and nodular calcification. All the parotid gland essence presented diffuse enhancement with irregular liquefactive necrosis, mildly swelling of adjacent platysma and fat, without enlargement of cervical lymph node.
ConclusionCT signs of parotid tuberculosis are closely related to its pathologic changes. For the lesions in unilateral parotid superficial lobe, we should consider the diagnosis of parotid lymph node tuberculosis with the signs of homogeneous enhancement, thickness of close platysma, subcutaneous fat and skin, and enlargement of cervical lymph node.
Objective To discuss the value of 64-slice spiral CT （MSCT） in diagnosis of gastric stromal tumor （GST）. Methods Thirty-two patients proved GST by surgery and pathology from May 2010 to August 2011 in West China Hospital, Sichuan University were classified by Fletcher malignancy degree classification，the CT features including the location，size，boundary，shape，density，growth pattern，metastases，and enhancement and its relationships to GST malignancy degree were analyzed retrospectively. Results All 32 cases were single lesion，the accuracy of CT in localization was 100%. Nine cases were intra-luminal，10 were extra-luminal，and 13 were both intra- and extra-luminal growth. Nine cases were in low degree group，with diameter＜5cm，round or oval in shape，clear border, homogenous density and enhancement （7/9）；Twenty-three cases were in high degree group，with diameter ≥5cm in 19 cases，irregular in shape and indistinct bourdry （18/23），heterogeneous density （20/23） with necrosis，ulcer was seen in 6 cases. Three cases in high malignance degree group showed pancreas and spleen involvements，2 cases of left diaphragm involvement，1 of omentum metastasis，2 of liver metastases，and 1 of lymph node metastasis. Conclusions MSCT is the optimal method to exam GST，there is correlation between the CT features and malignancy degree，MSCT is helpful for analyzing malignancy degree preoperation.
ObjectiveTo analyze the influencing factors for image quality of 18F-deoxyglucose (FDG) positron emission tomography (PET)/CT systemic tumor imaging and explore the method of control in order to improve the PET/CT image quality.
MethodsRetrospective analysis of image data from March to June 2011 collected from 1 000 18F-FDG whole body tumor imaging patients was carried out. We separated standard films from non-standard films according to PET/CT image quality criteria. Related factors for non-standard films were analyzed to explore the entire process quality control.
ResultsThere were 158 cases of standard films (15.80%), and 842 of non-standard films (84.20%). Artifact was a major factor for non-standard films (93.00%, 783/842) followed by patients’ injection information recording error (2.49%, 21/842), the instrument factor (1.90%, 16/842), incomplete scanning (0.95%, 8/842), muscle and soft tissue uptake (0.83%, 7/842), radionuclide contamination (0.59%, 5/842), and drug injection (0.24%, 2/842). The waste film rate was 5.80% (58/1 000), and the redoing rate was 2.20% (22/1 000).
ConclusionComplex and diverse factors affect PET/CT image quality throughout the entire process, but most of them can be controlled if doctors, nurses and technicians coordinate and cooperate with each other. The rigorous routine quality control of equipment and maintenance, patients’ full preparation, appropriate position and scan field, proper parameter settings, and post-processing technology are important factors affecting the image quality.
Precise segmentation of lung field is a crucial step in chest radiographic computer-aided diagnosis system. With the development of deep learning, fully convolutional network based models for lung field segmentation have achieved great effect but are poor at accurate identification of the boundary and preserving lung field consistency. To solve this problem, this paper proposed a lung segmentation algorithm based on non-local attention and multi-task learning. Firstly, an encoder-decoder convolutional network based on residual connection was used to extract multi-scale context and predict the boundary of lung. Secondly, a non-local attention mechanism to capture the long-range dependencies between pixels in the boundary regions and global context was proposed to enrich feature of inconsistent region. Thirdly, a multi-task learning to predict lung field based on the enriched feature was conducted. Finally, experiments to evaluate this algorithm were performed on JSRT and Montgomery dataset. The maximum improvement of Dice coefficient and accuracy were 1.99% and 2.27%, respectively, comparing with other representative algorithms. Results show that by enhancing the attention of boundary, this algorithm can improve the accuracy and reduce false segmentation.
ObjectiveTo investigate the value of rectumaerated MSCT examination in diagnosis of mesorectal infiltration of rectal cancer and lymph node metastasis staging. MethodsFrom January 2010 to July 2010, the data of 68 patients with rectal cancer confirmed by pathology were analyzed in the First Affiliated Hospital of Liaoning Medical University. All the patients underwent rectumaerated MSCT preoperatively and postoperative pathology was taken as the gold standard for evaluation of the accuracy, sensitivity, specificity, positive or negative predictive values of MSCT in diagnosis of mesorectal infiltration and lymph node metastasis.ResultsIn rectum-aerated MSCT scanning, rectum and sigmoid colon was fully expanded, perirectal fat space was clear between perirectal fat space and relatively high density rectal wall and very low density enteric cavity. For mesorectal infiltration of degree Ⅰ, Ⅱ, and Ⅲ, the accuracies were 92.6%（63/68）, 91.1%(62/68), and 95.6%(65/68), respectively; sensitivities were 91.2%(31/34), 85.0%(17/20), and 92.9%(13/14), respectively; specificities were 94.1%(32/34), 93.8%(45/48), and 96.3%(52/54), respectively; positive predictive values were 93.9%(31/33), 85.0%(17/20), and 86.7%(13/15), respectively; negative predictive values were 91.4%(32/35), 93.8%(45/48), and 98.1%(52/53), respectively. For lymph node metastasis in N0, N1, and N2, the accuracies were 92.6%(63/68）,85.3%(58/68）, and 92.6%(63/68）, respectively; sensitivities were 86.2%(25/29), 90.0%(27/30), and 66.7%(6/9), respectively; specificities were 97.4%(38/39), 81.6%(31/38), and 96.6%(57/59), respectively; positive predictive values were 96.2%(25/26), 79.4%(27/34), and 75.0%(6/8), respectively; negative predictive values were 90.5%(38/42), 92.1%(35/38), and 95.0%(57/60), respectively. ConclusionsRectumaerated MSCT scaning can clearly show the depth of rectal carcinoma infiltration in the mesorectum, and N staging of mesorectal lymph node metastasis of MSCT has a higher consistency with that of pathological staging. Rectumaerated MSCT scanning is an important referenced method for clinical preoperative staging and individualized chemotherapy regimen.
