Super U-Net: a modularized generalizable architecture.

Objective: To develop and validate a novel convolutional neural network (CNN) termed "Super U-Net" for medical image segmentation. Methods: Super U-Net integrates a dynamic receptive field module and a fusion upsampling module into the classical U-Net architecture. The model was developed and tested to segment retinal vessels, gastrointestinal (GI) polyps, skin lesions on several image types (i.e., fundus images, endoscopic images, dermoscopic images). We also trained and tested the traditional U-Net architecture, seven U-Net variants, and two non-U-Net segmentation architectures. K-fold cross-validation was used to evaluate performance. The performance metrics included Dice similarity coefficient (DSC), accuracy, positive predictive value (PPV), and sensitivity. Results: Super U-Net achieved average DSCs of 0.808±0.0210, 0.752±0.019, 0.804±0.239, and 0.877±0.135 for segmenting retinal vessels, pediatric retinal vessels, GI polyps, and skin lesions, respectively. The Super U-net consistently outperformed U-Net, seven U-Net variants, and two non-U-Net segmentation architectures (p < 0.05). Conclusion: Dynamic receptive fields and fusion upsampling can significantly improve image segmentation performance.

A rare presentation of panitumumab-involved interstitial lung disease: Spontaneous pneumomediastinum.

INTRODUCTION: Developments in targeted molecular therapies have considerably improved patient survival in cancer. Panitumumab is a monoclonal antibody against the epidermal growth factor receptor (EGFR). It is used to treat metastatic colorectal carcinoma. Although panitumumab is well tolerated in most patients, pulmonary toxicity, especially interstitial lung disease (ILD), is a life-threatening condition. The presentation of panitumumab-induced ILD with spontaneous pneumomediastinum and subcutaneous emphysema is rarely reported. CASE REPORT: We describe a 61-year-old male with metastatic colorectal carcinoma treated with FOLFIRI (folinic acid, 5-fluorouracil, irinotecan) and panitumumab. He presented to our hospital with a complaint of severe dyspnea. On the evaluation of dyspnea, the patient was diagnosed with ILD. MANAGEMENT AND OUTCOME: After exclusion of other common causes of pneumomediastinum and subcutaneous emphysema, panitumumab was attributed as a cause of ILD. Oxygen therapy via high flow nasal cannula and intravenous methylprednisolone regimen was started. After two weeks, the patient became asymptomatic with the radiologic amelioration. DISCUSSION: Panitumumab-induced ILD is associated with a poor prognosis and might occur randomly in one year after the drug administration. The possibility of the disease should be considered on every admission. Early recognition, discontinuation of causative medication, and immediate glucocorticoid therapy are essential to reduce mortality.

Evaluation of vertebral bone mineral density in scoliosis by using quantitative computed tomography.

PURPOSE: Scoliosis is described as a lateral curvature of the spine. We aimed to evaluate bone mineral density (BMD) in patients with scoliosis by using quantitative computed tomography (QCT) and compare the BMD of idiopathic and congenital scoliosis patients. MATERIAL AND METHODS: Forty-three patients aged 1 to 40 years with idiopathic, congenital, or neuromuscular scoliosis and 41 matched controls of the same sex and approximate age were included in the study. Measurements of BMD were performed by QCT analysis for each vertebral body from T12 to L5, and mean BMD was calculated for each case. RESULTS: Twenty-two of the patients with scoliosis were idiopathic, 15 were congenital, four were neuromuscular, and two were neurofibromatosis. The mean BMD values of patients with scoliosis were significantly lower compared with the control group (106.8 ± 33.4 mg/cm3 vs. 124.9 ± 29.1 mg/cm3, p = 0.009). No significant difference in BMD values was found between idiopathic and congenital scoliosis patients (p > 0.05). CONCLUSIONS: This study illustrated that the vertebral body BMD values of the patients with scoliosis were significantly lower than those seen in the control group.

Systematic Parameterization, Storage, and Representation of Volumetric DICOM Data.

Tomographic medical imaging systems produce hundreds to thousands of slices, enabling three-dimensional (3D) analysis. Radiologists process these images through various tools and techniques in order to generate 3D renderings for various applications, such as surgical planning, medical education, and volumetric measurements. To save and store these visualizations, current systems use snapshots or video exporting, which prevents further optimizations and requires the storage of significant additional data. The Grayscale Softcopy Presentation State extension of the Digital Imaging and Communications in Medicine (DICOM) standard resolves this issue for two-dimensional (2D) data by introducing an extensive set of parameters, namely 2D Presentation States (2DPR), that describe how an image should be displayed. 2DPR allows storing these parameters instead of storing parameter applied images, which cause unnecessary duplication of the image data. Since there is currently no corresponding extension for 3D data, in this study, a DICOM-compliant object called 3D presentation states (3DPR) is proposed for the parameterization and storage of 3D medical volumes. To accomplish this, the 3D medical visualization process is divided into four tasks, namely pre-processing, segmentation, post-processing, and rendering. The important parameters of each task are determined. Special focus is given to the compression of segmented data, parameterization of the rendering process, and DICOM-compliant implementation of the 3DPR object. The use of 3DPR was tested in a radiology department on three clinical cases, which require multiple segmentations and visualizations during the workflow of radiologists. The results show that 3DPR can effectively simplify the workload of physicians by directly regenerating 3D renderings without repeating intermediate tasks, increase efficiency by preserving all user interactions, and provide efficient storage as well as transfer of visualized data.

Evaluation of an unusual ossicle by multi-detector computed tomography: Oppenheimer's ossicle.

Variations and anomalies of the neural arch result from alterations in the ossification process. Absence of lumbar articular process is a rare anomaly which most commonly involves the inferior articular process of the L4 or L5 vertebrae. Non-union at the tip of the articular process is a more common variation, known as Oppenheimer's ossicle. In this case report, we present multi-detector computed tomography findings of Oppenheimer's ossicles in 2 separate cases.

Semi-automatic segmentation methods for 3-D visualization and analysis of the liver.

Pre-evaluation of donors prior to surgery of living donated liver transplantation is one of the challenging applications that computer aided systems are needed. The precise measurement of liver volume requires effective segmentation procedures, while three dimensional rendering of the segmented data provides demonstrative information to radiologists and surgeons before surgery. The Insight Toolkit provides effective algorithms for segmentation, which are also optimized for high computational performance and processing time. Furthermore, An ITK pipeline can be combined with a VTK pipeline, so that the result of segmentation can be represented directly in 3-D using VTK. Therefore, there is an on-going trend for developing ITK/VTK based systems. This study presents quantitative and qualitative performance evaluation of two effective ITK algorithms on segmentation of liver from CTA data sets.