B-type ultrasound images have important applications in medical diagnosis. However, the widely spread intensity inhomogeneity, low-scale contrast, constructed defect, noise and blurred edges all make it difficult to implement automatic segmentation of lesion in the images. Based on region level set method, a subordinate degree region level set model was proposed, in which subordinate degree probability of each pixel was defined to reflect the pixel subjection grade to target and background respectively. Pixels were classified to either target or background by calculation of their subordinate degree probabilities, and edge contour was obtained by region level set iterations. In this paper, lesion segmentation is regarded as local segmentation of specific area, and the calculation is restrained to the local sphere abide by the contour, which greatly reduce the calculation complexity. Experiments on B-type ultrasound images showed improved results of the proposed method compared to those of some popular level set methods.
ObjectiveTo explore the effectiveness of clinical pathway (CP) in patients underwent laparoscopic cholecystectomy (LC). MethodsA retrospective, case-matched, and clinical controlled study was applied. We selected patients with acute calculous cholecystitis (ACC) who were hospitalized in 363 Hospital and underwent LC between September 2012 and August 2013, and divided them into two groups (non-CP vs. CP:2 to 1) according to sex, age (±5), nation and complications. The indicators including length of stay (LOS), antibiotic usage and per-average hospital expenses were compared between groups. Data were analyzed using SPSS 13.0 software. ResultsA total of 1 044 patients were included, of which 348 were assigned to CP management (CP group), while the other 696 patients were 2 to 1 matched with those in the CP group. Compared to the non-CP group, the pre-operation LOS and total LOS in the CP group were shortened by 1.23 days and 2.08 days, respectively (P < 0.05); the per-average hospital expenses and per-average expenses of drugs in the CP group were decreased by ￥604.7 yuan and ￥287.5 yuan, respectively (P < 0.05); and the rate of antibiotic and non-restricted antibiotic usage in the CP group were dropped by 4.4% and 7.0%, respectively (P < 0.05). There was no significant difference between the groups in efficiency, hospital-related infection rate, the incidence of adverse events, the restricted and special antibiotic usage rate (P > 0.05). The variation coefficient of patients included in the CP group was 15.8%, and the time which did not meet the admission requirement of CP was the main reason for this variation (27, 49.1%). ConclusionClinical pathway could shorten the LOS and cut down the total hospital expenses. However, multidisciplinary cooperation is still needed, and we should optimize the CP processes continuously and enhance the flexibility of CP, so as to improve the quality of medical service.