31 research outputs found
Computational Model for Human 3D Shape Perception From a Single Specular Image
In natural conditions the human visual system can estimate the 3D shape of specular objects even from a single image. Although previous studies suggested that the orientation field plays a key role for 3D shape perception from specular reflections, its computational plausibility, and possible mechanisms have not been investigated. In this study, to complement the orientation field information, we first add prior knowledge that objects are illuminated from above and utilize the vertical polarity of the intensity gradient. Then we construct an algorithm that incorporates these two image cues to estimate 3D shapes from a single specular image. We evaluated the algorithm with glossy and mirrored surfaces and found that 3D shapes can be recovered with a high correlation coefficient of around 0.8 with true surface shapes. Moreover, under a specific condition, the algorithm's errors resembled those made by human observers. These findings show that the combination of the orientation field and the vertical polarity of the intensity gradient is computationally sufficient and probably reproduces essential representations used in human shape perception from specular reflections
Clinical significance in the number of involved lymph nodes in patients that underwent surgery for pathological stage III-N2 non-small cell lung cancer
<p>Abstract</p> <p>Purpose</p> <p>This study investigated whether the number of involved lymph nodes is associated with the prognosis in patients that underwent surgery for pathological stage (p-stage) III/N2 NSCLC.</p> <p>Subjects</p> <p>This study evaluated 121 patients with p-stage III/N2 NSCLC.</p> <p>Results</p> <p>The histological types included 65 adenocarcinomas, 39 squamous cell carcinomas and 17 others. The average number of dissected lymph nodes was 23.8 (range: 6-55). The average number of involved lymph nodes was 5.9 (range: 1-23). The 5-year survival rate of the patients was 51.0% for single lymph node positive, 58.9% for 2 lymph nodes positive, 34.2% for 3 lymph nodes positive, and 30.0% for 4 lymph nodes positive, and 20.4% for more than 5 lymph nodes positive. The patients with either single or 2 lymph nodes positive had a significantly more favorable prognosis than the patients with more than 5 lymph nodes positive. A multivariate analysis revealed that the number of involved lymph nodes was a significant independent prognostic factor.</p> <p>Conclusion</p> <p>Surgery appears to be preferable as a one arm of multimodality therapy in p-stage III/N2 patients with single or 2 involved lymph nodes. The optimal incorporation of surgery into the multimodality approach therefore requires further clinical investigation.</p
What factors predict recurrence of a spontaneous pneumothorax?
Abstract Background The purpose of this retrospective study was to identify the risk factors for postoperative recurrence for the patients with a spontaneous pneumothorax (SP). A total of 214 patients were studied over a period of five years. Of these patients, 189 (88.3%) and 25 (11.7%) underwent video assisted thoracoscopic surgery (VATS) and an open approach for treatment, respectively. There were 35 (16.4%) postoperative recurrences. Methods The data on patient characteristics, surgical details, and perioperative outcomes were analyzed. We compared the clinicopathological characteristics between recurrent and non-recurrent cases, and used logistic regression models to predict the risk factors for postoperative recurrence. Results The differences in the age, gender, lesion site, location, ipsilateral SP (ISP), and contralateral SP (CSP) did not reach statistical significance between the two groups. However, the incidence of recurrence was higher in the subjects without any smoking history, and who had comorbidities, and a history of surgery for ISP. Concerning intraoperative factors, there were no significant differences with regard to the approach, buttress stapling, covering, surgeon, or length of the operation. The postoperative recurrence rate was higher in the patients who had been hand-stitched compared to those who had undergone instrument-based repair for blebs. There were no significant differences in the perioperative outcomes. The logistic regression models indicated that non smokers, those with comorbidities, and those who had previously undergone surgery for ISP had a higher rate of postoperative recurrence. Conclusions We conclude that a history of no smoking, the existence of comorbidities, previous surgery for ISP, and hand stitching increase the risk of postoperative recurrence. Therefore, surgeons must be aware of these risk factors, and more carefully monitor such patients for recurrence.</p
Discriminative features of thin-slice computed tomography for peripheral intrapulmonary lymph nodes
The use of computed tomography (CT) scans has increased the opportunities to detect small nodular shadows in peripheral lung fields. Intrapulmonary lymph nodes (IPLNs) are sometimes identified among these nodular shadows, and a differential diagnosis is often difficult. However, few descriptions of the CT findings of IPLNs, with regard to their potential for the differential diagnosis of lung cancer, have been published. From 2006 through 2011, 606 patients underwent thoracic surgery for pulmonary nodules. Nine patients (1.5%) had pathologically diagnosed IPLNs. We retrospectively reviewed the clinicopathological features and thin-section CT findings of the patients with IPLNs. We also compared these IPLN patients with 17 patients having small-sized lung cancer. In six cases, the nodules were round, and linear density extending from the IPLNs was visualized in seven nodules. The nodules in IPLNs were located in the lower lobe, and the nodule borders were clearer than those of lung cancers. Six out of nine nodules were round, and linear densities were more easily visualized for the IPLNs. Medical specialists need to be familiar with the discriminative features of thin-slice CT for IPLNs not only to avoid performing unnecessary operations, but also to prevent the mis-staging of lung cancer
Discriminative features of thin-slice computed tomography for peripheral intrapulmonary lymph nodes
SummaryBackgroundThe use of computed tomography (CT) scans has increased the opportunities to detect small nodular shadows in peripheral lung fields. Intrapulmonary lymph nodes (IPLNs) are sometimes identified among these nodular shadows, and a differential diagnosis is often difficult. However, few descriptions of the CT findings of IPLNs, with regard to their potential for the differential diagnosis of lung cancer, have been published.MethodsFrom 2006 through 2011, 606 patients underwent thoracic surgery for pulmonary nodules. Nine patients (1.5%) had pathologically diagnosed IPLNs. We retrospectively reviewed the clinicopathological features and thin-section CT findings of the patients with IPLNs. We also compared these IPLN patients with 17 patients having small-sized lung cancer.ResultsIn six cases, the nodules were round, and linear density extending from the IPLNs was visualized in seven nodules. The nodules in IPLNs were located in the lower lobe, and the nodule borders were clearer than those of lung cancers. Six out of nine nodules were round, and linear densities were more easily visualized for the IPLNs.ConclusionMedical specialists need to be familiar with the discriminative features of thin-slice CT for IPLNs not only to avoid performing unnecessary operations, but also to prevent the mis-staging of lung cancer
Results of surgical resection for patients with thymoma according to World Health Organization histology and Masaoka staging
Thymomas are relatively rare tumors. In this study, we investigated the clinical features of patients who underwent surgical resection for thymoma. This study clinicopathologically evaluated 54 consecutive patients who underwent a surgical resection of thymoma in our department between 1994 and 2006. A complete resection was performed in 52 patients, while two patients underwent an incomplete resection due to pleural dissemination. Combined resection with adjacent organs was performed for the lung (n = 6), pericardium (n = 5), and large vessels (brachiocephalic vein in three, superior vena cava in two). The concomitant autoimmune diseases were observed in 20 patients (37%), and they included myasthenia gravis in 17 patients, macroglobulinemia in one, pemphigus vulgaris in one, and stiff person syndrome in one patient. The histologic types of the World Health Organization classification diagnosed as type A in four patients, type AB in 14, type B1 in eight, type B2 in 15, and type B3 in 11. There were 27, 17, eight, and two patients with Masaoka stages I, II, III, and IV, respectively. Four patients died, and the causes of death included recurrence of thymoma in two, gastric carcinoma in one, and respiratory failure due to myasthenia gravis in one patient. The overall survival rate at 10 years was 94.6% in patients with stages I and II disease and 77.1% in patients with stages III and IV disease. Long-term survival can be expected not only for patients at early stages, as well as for patients with stages III and IV disease if surgical resection is completed macroscopically
Discrepancy between the Clinical Image and Pathological Findings of Non-Small Cell Lung Cancer Harboring an Epidermal Growth Factor Receptor Gene Mutation That Was Surgically Resected after Gefitinib Treatment
We herein describe a discrepancy between the clinical image and pathological findings in a non-small cell lung cancer patient with an epidermal growth factor receptor (EGFR) mutation who underwent surgical resection after gefitinib treatment. The patient was a 66-year-old female with c-stage IIIA lung adenocarcinoma harboring an EGFR gene mutation; she was surgically treated after receiving gefitinib. The pathological examination revealed adenocarcinoma, and the pathologically therapeutic effect was considered to be slight or of no response. EGFR T790M mutation and MET amplification were not present. The pathologically therapeutic effect is generally well correlated with the response rate after induction therapy. In this case, there was a discrepancy between the clinical image and pathological findings. Our findings, therefore, raise questions about the role of surgery after EGFR-tyrosine kinase inhibitor treatment
Results of surgical resection for patients with thymoma according to World Health Organization histology and Masaoka staging
Objectives: Thymomas are relatively rare tumors. In this study, we investigated the clinical features of patients who underwent surgical resection for thymoma.
Patients and methods: This study clinicopathologically evaluated 54 consecutive patients who underwent a surgical resection of thymoma in our department between 1994 and 2006.
Results: A complete resection was performed in 52 patients, while two patients underwent an incomplete resection due to pleural dissemination. Combined resection with adjacent organs was performed for the lung (n=6), pericardium (n=5), and large vessels (brachiocephalic vein in three, superior vena cava in two). The concomitant autoimmune diseases were observed in 20 patients (37%), and they included myasthenia gravis in 17 patients, macroglobulinemia in one, pemphigus vulgaris in one, and stiff person syndrome in one patient. The histologic types of the World Health Organization classification diagnosed as type A in four patients, type AB in 14, type B1 in eight, type B2 in 15, and type B3 in 11. There were 27, 17, eight, and two patients with Masaoka stages I, II, III, and IV, respectively. Four patients died, and the causes of death included recurrence of thymoma in two, gastric carcinoma in one, and respiratory failure due to myasthenia gravis in one patient. The overall survival rate at 10 years was 94.6% in patients with stages I and II disease and 77.1% in patients with stages III and IV disease.
Conclusions: Long-term survival can be expected not only for patients at early stages, as well as for patients with stages III and IV disease if surgical resection is completed macroscopically