Biodistribution and estimation of radiation-absorbed doses in humans for 13N-ammonia PET/CT / 中国医学影像技术

Objective To evaluate the biodistribution and radiation-absorbed doses of main organs in healthy people with 13 N-ammonia.Methods Five healthy volunteers underwent whole-body PET and CT scans after injection of 666-814 MBq of 13 N-ammonia.The serial dynamic emission images of each healthy volunteer were acquired.ROI were drawn manually based on the transverse CT images and transferred to the corresponding PET slices.Radiation-absorbed doses were calculated using the medical internal radiation dosimetry (MIRD) method.Results The highest concentrations of 13 N-ammonia were found in the heart,liver and kidneys,followed by pancreas,brain,spleen and stomach.The organ of highest absorbed dose was heart with (7.14±3.63) × 10-3 mGy/MBq.The whole-body absorbed dose was (2.11±0.44) × 10 3 mGy/MBq.The whole-body effective dose was (6.58± 1.23) × 10-3 mSv/MBq.Conclusion As one of the most important myocardial perfusion tracers,the whole-body 13 N-NH3 · H2 O PET appears to be safe for humans.

Study of sharing platform of web-based enhanced extracorporeal counterpulsation hemodynamic waveform data / 生物医学工程学杂志

Enhanced extracorporeal counterpulsation (EECP) information consists of both text and hemodynamic waveform data. At present EECP text information has been successfully managed through Web browser, while the management and sharing of hemodynamic waveform data through Internet has not been solved yet. In order to manage EECP information completely, based on the in-depth analysis of EECP hemodynamic waveform file of digital imaging and communications in medicine (DICOM) format and its disadvantages in Internet sharing, we proposed the use of the extensible markup language (XML), which is currently the Internet popular data exchange standard, as the storage specification for the sharing of EECP waveform data. Then we designed a web-based sharing system of EECP hemodynamic waveform data via ASP. NET 2.0 platform. Meanwhile, we specifically introduced the four main system function modules and their implement methods, including DICOM to XML conversion module, EECP waveform data management module, retrieval and display of EECP waveform module and the security mechanism of the system.

The compression and storage of enhanced external counterpulsation waveform based on DICOM standard / 生物医学工程学杂志

The development of external counterpulsation (ECP) local area network system and extensible markup language (XML)-based remote ECP medical information system conformable to digital imaging and communications in medicine (DICOM) standard has been improving the digital interchangeablity and sharability of ECP data. However, the therapy process of ECP is a continuous and longtime supervision which builds a mass of waveform data. In order to reduce the storage space and improve the transmission efficiency, the waveform data with the normative format of ECP data files have to be compressed. In this article, we introduced the compression arithmetic of template matching and improved quick fitting of linear approximation distance thresholding (LADT) in combimation with the characters of enhanced external counterpulsation (EECP) waveform signal. The DICOM standard is used as the storage and transmission standard to make our system compatible with hospital information system. According to the rules of transfer syntaxes, we defined private transfer syntax for one-dimensional compressed waveform data and stored EECP data into a DICOM file. Testing result indicates that the compressed and normative data can be correctly transmitted and displayed between EECP workstations in our EECP laboratory.