A 2.4GHz Low Power ASK Transmitter for Wireless Capsule Endoscope Applications

A 2.4GHz ASK transmitter suitable for a low power wireless capsule endoscope system is presented. A mixer-based frequency up-conversion transmitter architecture is employed to achieve a high data rate. A pseudodifferential stacked class-A power amplifier using the current reuse technique is proposed to save power. The transmitter mainly includes two parts： a 20MHz ASK modulator based on a constant amplitude phase lock loop （PLL） and a direct up-conversion RF circuit. This design, implemented in a TSMC 0.25μm CMOS process, achieves a - 23. 217dBm output power with a data rate of 1Mbps and dissipates 3.17mA of current with a single 2.5V power supply.

A novel intelligent chromo capsule endoscope for the diagnosis of neoplastic lesions in the gastrointestinal tract

Background:Chromoendoscopy has not been fully integrated into capsule endoscopy.This study aimded to develop and validate a novel intelligent chromo capsule endoscope(ICCE).Methods:The ICCE has two modes:a white-light imaging(WLI)mode and an intelligent chromo imaging(ICI)mode.The performance of the ICCE in observing colors,animal tissues,and early gastrointestinal(GI)neoplastic lesions in humans was evaluated.Images captured by the ICCE were analysed using variance of Laplacian(VoL)values or image contrast evaluation.Results:For color observation,conventional narrow-band imaging endoscopes and the ICI mode of the ICCE have similar spectral distributions.Compared with the WLI mode,the ICI mode had significantly higher VoL values for animal tissues(2.15461.044 vs 3.80061.491,P=0.003),gastric precancerous lesions and early gastric cancers(2.24260.162 vs 6.64260.919,P<0.001),and colon tumors(3.89661.430 vs 11.88267.663,P<0.001),and significantly higher contrast for differentiating tumor and non-tumor areas(0.06960.046 vs 0.14460.076,P=0.005).More importantly,the sensitivity,specificity,and accuracy of the ICI mode for early GI tumors were 95.83%,91.67%,and 94.64%,respectively,which were significantly higher than the values of the WLI mode(78.33%[P<0.001],77.08%[P=0.01],and 77.98%[P<0.001],respectively).Conclusions:We successfully integrated ICI into the capsule endoscope.The ICCE is an innovative and useful tool for differential diagnosis based on contrast-enhanced images and thus has great potential as a superior diagnostic tool for early GI tumor detection.

Development of a Wireless Capsule Endoscope System Based on Field Programmable Gate Array

A new modular and programmable wireless capsule endoscope is presented in this paper. The capsule system consumes low power and has small physical size. A new image compression algorithm is presented in this paper to reduce power consumption and silicon area. The compression algorithm includes color space transform, uniform quantization, sub-sampling, differential pulse code modulation (DPCM) and Golomb-Rice code. The algorithm is tested in a field programmable gate array (FPGA) development board, and the final result achieves 80% compression rate at 40 dB peak signal to noise ratio (PSNR). The algorithm has high image compression efficiency and low power consumption, compared to other existing works. The system is composed of the following three parts: image capsule endoscope, portable wireless receiver and host computer software. The software and hardware design of the three parts are disscussed in details. © 2017, Shanghai Jiaotong University and Springer-Verlag Berlin Heidelberg.

Optimized Identification with Severity Factors of Gastric Cancer for Internet of Medical Things

The Internet of Medical Things (IoMT) emerges with the visionof the Wireless Body Sensor Network (WBSN) to improve the health monitoringsystems and has an enormous impact on the healthcare system forrecognizing the levels of risk/severity factors (premature diagnosis, treatment,and supervision of chronic disease i.e., cancer) via wearable/electronic healthsensor i.e., wireless endoscopic capsule. However, AI-assisted endoscopy playsa very significant role in the detection of gastric cancer. Convolutional NeuralNetwork (CNN) has been widely used to diagnose gastric cancer based onvarious feature extraction models, consequently, limiting the identificationand categorization performance in terms of cancerous stages and gradesassociated with each type of gastric cancer. This paper proposed an optimizedAI-based approach to diagnose and assess the risk factor of gastric cancerbased on its type, stage, and grade in the endoscopic images for smarthealthcare applications. The proposed method is categorized into five phasessuch as image pre-processing, Four-Dimensional (4D) image conversion,image segmentation, K-Nearest Neighbour (K-NN) classification, and multigradingand staging of image intensities. Moreover, the performance of theproposed method has experimented on two different datasets consisting ofcolor and black and white endoscopic images. The simulation results verifiedthat the proposed approach is capable of perceiving gastric cancer with 88.09%sensitivity, 95.77% specificity, and 96.55% overall accuracy respectively.

Two cameras detect more lesions in the small-bowel than one

AIM:To explore the feasibility of dual camera capsule (DCC)small-bowel(SB)imaging and to examine if two cameras complement each other to detect more SB lesions.METHODS:Forty-one eligible,consecutive patients underwent DCC SB imaging.Two experienced investigators examined the videos and compared the total number of detected lesions to the number of lesions detected by each camera separately.Examination tolerability was assessed using a questionnaire.RESULTS:One patient was excluded.DCC cameras detected 68 positive findings(POS)in 20(50%)cases.Fifty of them were detected by the"yellow"camera,48 by the"green"and 28 by both cameras;44%(n=22)of the"yellow"camera’s POS were not detected by the"green"camera and 42%(n=20)of the"green" camera’s POS were not detected by the"yellow"camera.In two cases,only one camera detected significant findings.All participants had 216 findings of unknown significance(FUS).The"yellow","green"and both cameras detected 171,161,and 116 FUS,respectively;32%(n=55)of the"yellow"camera’s FUS were not detected by the"green"camera and 28%(n=45)of the"green"camera’s FUS were not detected by the "yellow"camera.There were no complications related to the examination,and 97.6%of the patients would repeat the examination,if necessary.CONCLUSION:DCC SB examination is feasible and well tolerated.The two cameras complement each other to detect more SB lesions.

Smart Image Sensor with Integrated Low Complexity Image Processing for Wireless Endoscope Capsules

A smart image sensor was developed which integrates a digital pixel image sensor array with an image processor, designed for wireless endoscope capsules. The camera-on-a-chip architecture and its on-chip functionality facilitate the design of the packaging and power consumption of the integrated capsule. The power reduction techniques were carried out at both the architectural and circuit level. Gray coding and power gating in the sensor array to eliminate almost 50% of the switch activity on the data bus and more than 99% of the power dissipation in each pixel at a transmitting rate of 2 frames per second. Filtering and compression in the processor reduces the data transmission by more than 2/3. A parallel fully pipelined architecture with a dedicated clock management scheme was implemented in the JPEG-LS engine to reduce the power consumption by 15.7%. The smart sensor has been implemented in 0.18 μm CMOS technology.

A simple and inexpensive enteric-coated capsule for delivery of acid-labile macromolecules to the small intestine

Understanding the ecology of the gastrointestinal tract and the impact of the contents on the host mucosa is emerging as an important area for defining both wellness and susceptibility to disease. Targeted delivery of drugs to treat specific small intestinal disorders such as small bowel bacterial overgrowth and targeting molecules to interrogate or to deliver vaccines to the remote regions of the small intestine has proven difficult. There is an unmet need for methodologies to release probes/drugs to remote regions of the gastrointestinal tract in furthering our understanding of gut health and pathogenesis. In order to address this concern, we need to know how the regional delivery of a surrogate labeled test compound is handled and in turn, if delivered locally as a liquid or powder, the dynamics of its subsequent handling and metabolism. In the studies we report on in this paper, we chose ^13 C sodium acetate（^13C-acetate）, which is a stable isotope probe that once absorbed in the small intestine can be readily measured non-invasively by collection and analysis of ^13CO2 in the breath. This would provide information of gastric emptying rates and an indication of the site of release and absorptive capacity. In a series of in vitro and in vivo pig experiments, we assessed the enteric-protective properties of a commercially available polymer EUDRAGIT L100-55 on gelatin capsules and also on DRcaps. Test results demonstrated that DRcaps coated with EUDRAGIT L100-55 possessed enhanced enteric-protective properties, particularly in vivo. These studies add to the body of knowledge regarding gastric emptying in pigs and also begin the process of gathering specifications for the design of a simple and cost-effective enteric-coated capsule for delivery of acid-labile macromolecules to the small intestine.

Magnetic Actuation Systems and Magnetic Robots for Gastrointestinal Examination and Treatment

Magnetic actuation technology(MAT)provides novel diagnostic tools for the early screening and treatment of digestive cancers,which have high morbidity and mortality rates worldwide.The application of magnetic actuation systems and magnetic robots in gastrointestinal(GI)diagnosis and treatment to provide a comprehensive reference manual for scholars in the field of MAT research are reviewed.It describes the basic principles of magnetic actuation and magnetic field safety,introduces the design,manufacturing,control,and performance parameters of magnetic actuation systems,as well as the applicability and limitations of each system for different parts of the GI tract.It analyzes the characteristics and advantages of different types and functions of magnetic robots,summarizes the challenges faced by MAT in clinical applications,and provides an outlook on the future prospects of the field.

Efficiency analysis and optimization of wireless power transfer system for freely moving biomedical implants

In the wireless power transfer system for freely moving biomedical implants,the receiving unit was generally inefficient for the reason that its design parameters including the receiving coil's dimension and receiving circuits' topology were always determined by experiments.In order to build the relationship between these parameters and the total transfer efficiency,this paper developed a novel efficiency model based on the impedance model of the coil and the circuit model of the receiving circuits.According to the design constraints,the optimal design parameters in the worst case were derived.The results indicate that the combination of the two-layered receiving coil and half-bridge rectifier has more advantages in size,efficiency and safety,which is preferred in the receiving unit.Additionally,when the load resistance increases,the optimal turn number of the receiving coil basically keeps constant and the corresponding transmitting current and total efficiency decrease.For 100 Ω load,the transmitting current and total efficiency in the worst case were measured to be 5.30 A and 1.45% respectively,which are much better than the published results.In general,our work provides an efficient method to determine the design parameters of the wireless power transfer system for freely moving biomedical implants.