Comparison Of Radiographic Techniques In Diagnosis Of Pneumoconiosis And Research On Optimization Of Whole Lung Lavage Applied To Pneumoconiosis

OBJECTIVE:1. To evaluate the applicability of direct digital radiography (DDR) images in identification of pneumoconiosis, we compared the shape/size and profusion of small opacities between film screen radiograph (FSR) and DDR technique.2. To find out DDR image processing preferences suitable for technical quality requirement for diagonosis of pneumoconiosis.METHODS:1. By measuring optical density of DDR printed film and readers’assessing of film quality, we tried to find out more suitable image processing preferences to reach the film quality requirement for pneumoconiosis diagnosis.2. We enrolled 204 pneumoconioses patients and 31 dust workers during the course of the study with FSR and DDR images obtained from all participants. Five readers interpreted 29 FSRs and 29 DDRs all from earliest enrolled 29 study subjects twice, respectively. Agreement and kappa analysis was done in order to assess inter-reader and intra- reader agreement.3. Five readers’panel readed FSR and DDR separately, and small opacity shape/size, profusion by zone, overall profusion, large opacity and severity stage were recorded.. The kappa analysis was made. RESULTS:1. Among the image processing parameters, contrast adjust (CA) and brightness adjust (BA) charged for gray adjust, when they were set at 116% and 164%, the image gray is the most suitable for pneumoconiosis diagnosis requirement. And the film optical density reached that requirement. As a suggestion for other index, noise reduction = 0; edge = 4; tissue equalization in over-penetrated area = 6%, strength = 13%, uner-penetrated area = 20%, strength = 49%. In that condition, image resolusion was good, lung texture reached outer of lung field and lung texture behind heart and liver could discern on DDR film.2. Five readers all had rather good intra-reader agreement (90%) on overall profusion and severity stages, with average kappa 0.82 of FSR and 0.70 of DDR. And they got similar agreement with that of FSR. Inter-reader analysis showed that the median kappa on overall profusion was 0.81 of FSR and 0.66 of DDR. Kappa values on severity stage were 0.79 and 0.80, respectively.3. The inter-modality agreement of small opacities by zone was good with a weighted kappa = 0.77. The agreement was high in the upper zones (κ=0.82), intermediate in the middle zones (κ=0.75) and low in the lower zones (κ=0.68). The identification of small opacities was close (93.2% FSR and 90.0% DDR).CONCLUSIONS:1. The image processing preferences played an important role in DDR image technical quality.2. Inter-reader and intra-reader agreement on FSRwas similar with on DDR.3. DDR images had superior quality to FSR, and were equivalent to the recognition or classification of small parenchymal lung opacities. OBJECTIVE: To observe and evaluate the application of pressure ventilation, adrenaline and pressure on saline on whole lung lavage (MWLL) in reducing hypoxemia during whole lung lavage and prompting water absorption in lung. METHODS: We enrolled 155 patients during the study that would undergo whole lung lavage. All the objects were randomly divided into five groups: pressure ventilation (PV) group, Ad group, PV+ Ad group, pressure bag (PB) group and saline group. 5 patients were excluded during the study for reasons no concerned with this research. The final numbers in groups above were 28, 31, 29, 30 and 32. Oxygen saturation, chest X-ray, clinical symptoms, lung functions were examined before and after MWLL.RESULT:1. No significantly differences in clinic symptoms among five groups before and after MWLL, P > 0.05.2. The Ad group got 6.3% increase on FVC and 10.9% on FEF25% after MWLL, P < 0.05. The saline group changed with decreasing 5.7% on FVC, increasing 10.9% and 12.0% on FEV1.0 and FEF25%, P < 0.05.3. The prevalence rate of SpO2?<?94% in PV group, Ad group, PV+ Ad group, PB group and saline group were 0, 4.8%, 0, 3.3% and 12.5%, P < 0.01.4. The residual fluid remained in lung during MWLL in all five groups were similar (P > 0.05). The optical density D-value between two lung fields on chest x-ray obtained within 3 hours after MWLL was lowest in PV+Ad÷group (0.152), then the PV group (0.194), compared with saline group (0.241) the differences were significantly (both P value less than 0.05). The OD D-value difference between Ad group and the saline group was minor (P>0.05).CONCLUSION:Pressure ventilation, adrenelin, and pressure on saline combined with MWLL were benefit to the transportation and absorption of residual fluid in lung and decreased the occurrences of hypoxemia.