Various Intragastric Balloons Under Clinical Investigation

Obesity is a chronic disease with an exponentially increasing incidence rate, and its negative effects are well documented in numerous studies. As a result, the importance of bariatric therapy cannot be overemphasized, and many bariatric treatment methods with varying mechanisms have been developed. Of the available treatment methods, intragastric balloons, introduced in the 1980s, have been shown to be a safe and effective treatment modality; various intragastric balloon products have been developed and are currently being widely used in clinical settings. However, the disadvantages of intragastric balloons, such as unclear long-term weight loss benefits and complications experienced during insertion and removal, preclude their wider use. In this review, we discuss different intragastric balloon products, focusing on those under clinical investigation, and suggest future research directions

Clinical Efficacy of Near-Infrared Reflectance Imaging and Optical Coherence Tomography in Identifying Ocular Manifestations of Neurofibromatosis Type 1 in Korean Children

Purpose The aim of this study was to investigate the clinical efficacy of near-infrared reflectance (NIR) imaging and optical coherence tomography (OCT) in identifying ocular manifestations of neurofibromatosis type 1 (NF1) in Korean children. Methods This retrospective chart review study included five Korean children with NF1 aged under 18 years who had undergone ophthalmic procedures, including slit-lamp examinations, NIR imaging, and OCT scanning. Results Multiple patchy bright lesions were observed on NIR imaging in all eyes (10 eyes in five patients). Further NIR imaging and OCT scans showed that these lesions, confined to the choroid, were choroidal nodules. Lisch nodules, contrastingly, were found in only four of 10 eyes by slit-lamp examinations on the same day as the NIR imaging. One of those four eyes had only one Lisch nodule, which did not meet the NF1 diagnostic criteria. Conclusion NIR imaging enabled the detection of choroidal nodules in Korean children with NF1. Moreover, for Korean children with NF1, choroidal nodules were earlier-detected ocular manifestations relative to Lisch nodules. NIR imaging, along with OCT, is a useful protocol for localizing NF1 nodules in children

Amplify-and-Forward Distributed Beamforming with Local CSI in the Presence of Interferences

This paper introduces an optimum amplify-and-forward (AF) distributed beamforming (DBF) in the presence of cochannel interference (CCI) when only local channel-state information (CSI) is available at each relay. It is shown that the proposed DBF closely achieves the performance obtained with global CSI when interference power toward relays is small or there are a large number of interferers but greatly reduces the complexity and overhead. The proposed DBF provides significant improvements over the conventional DBF designed without considering CCI at the cost of slightly increased complexity and overhead and achieves the capacity scaling of 1/2log⁡K through K relays, where 1/2log⁡K corresponds to the maximal capacity scaling when there is no CCI

Mesenteric extraskeletal osteosarcoma with telangiectatic features: a case report

<p>Abstract</p> <p>Background</p> <p>Extraskeletal osteosarcoma is a rare malignant mesenchymal tumor, with a predominant occurrence in the extremities. Only two cases of mesenteric extraskeletal osteosarcoma have been documented. We describe an unusual case of extraskeletal osteosarcoma with telangiectatic features occurring in the mesentery.</p> <p>Case presentation</p> <p>A 67-year-old male presented with blood-tinged stool of 1-month's duration. On colonoscopy, a solid mass was detected protruding from the colon wall. Computed tomography showed a 15 × 9.7 cm heterogeneously enhancing mass, with mottled calcification and a cystic portion, occupying the left upper quadrant of the abdominal cavity. Curative resection of the tumor was performed, and the excised tumor was composed of large multilocular cysts containing old hematomas and necrotic debris. The histology revealed an osteosarcoma showing osteoid formation and blood-filled spaces lined with atypical cells. Despite postoperative chemotherapy, he developed a recurrent peritoneal mass and multiple lung metastases 3 months postoperatively.</p> <p>Conclusion</p> <p>Given the rarity of cases of mesenteric extraskeletal osteosarcoma, its biologic behavior at this location remains to be determined. However, extraskeletal osteosarcoma with telangiectatic features is an uncommon entity to be recognized because of the possible fatal outcome related to the tumors.</p

Effectiveness of Doppler Image of the Vertebral Artery as an Anatomical Landmark for Identification of Ultrasound-Guided Target Level in Cervical Spine

Study DesignA prospective sonographic study.PurposeTo verify the effectiveness of simultaneous application of two landmarks, Doppler image of the vertebral artery and shape of the transverse tubercle of the seventh cervical (C7) vertebra.Overview of LiteratureCounting upwards from the C7 vertebra which only has a posterior tubercle of the transverse process is a commonly used method for ultrasound-guided cervical nerve root block. However, each transverse process has a different shape.MethodsSonograms of 20 volunteers were examined. At first, we identified the C7 transverse process based on the presence of the vertebral artery without the anterior tubercle. The C5 and C6 transverse processes were identified based on the presence of anterior tubercle without the vertebral artery. Subsequently, we placed needles on the C5, C6, and C7 transverse processes and the location and direction of needles were confirmed by fluoroscopy.ResultsIn the 120 segments, 93.3% of needles were placed correctly as desired; 97.5% of needles were placed on the 5C transverse process; 97.5% of needles were placed on the C6 transverse process; and 85.0% of needles were placed on the C7 transverse process, respectively. Both sides showed the same accuracy of 93.3%.ConclusionsSimultaneous application of Doppler image of the vertebral artery and shape of the C7 transverse tubercle showed 93.3% accuracy in identifying the target cervical level. Therefore, Doppler image of the vertebral artery can be considered to be a useful landmark for ultrasound-guided cervical nerve root block

Improved Correction of Atmospheric Pressure Data Obtained by Smartphones through Machine Learning

A correction method using machine learning aims to improve the conventional linear regression (LR) based method for correction of atmospheric pressure data obtained by smartphones. The method proposed in this study conducts clustering and regression analysis with time domain classification. Data obtained in Gyeonggi-do, one of the most populous provinces in South Korea surrounding Seoul with the size of 10,000 km2, from July 2014 through December 2014, using smartphones were classified with respect to time of day (daytime or nighttime) as well as day of the week (weekday or weekend) and the user’s mobility, prior to the expectation-maximization (EM) clustering. Subsequently, the results were analyzed for comparison by applying machine learning methods such as multilayer perceptron (MLP) and support vector regression (SVR). The results showed a mean absolute error (MAE) 26% lower on average when regression analysis was performed through EM clustering compared to that obtained without EM clustering. For machine learning methods, the MAE for SVR was around 31% lower for LR and about 19% lower for MLP. It is concluded that pressure data from smartphones are as good as the ones from national automatic weather station (AWS) network