ABSTRACT
Objective To prepare a novel loaded NdFeB and Fe3O4 liquid-solid phase inversion poly (polylactic-co-glycolic acid,PLGA) in situ implant (PLGA 60％ NdFeB-20％ Fe3O4) for ultrasound-guided intratumoral injection,and to investigate its intensity of magnetism and therapeutic efficiency of nude mice bearing MDA-MB-231 breast cancer.Methods PLGA-60 ％ NdFeB-20 ％ Fe3O4 in situ implant was prepared.The microstructure of PLGA-60 ％ NdFeB-20 ％ Fe3O4 was tested with scanning electron microscope (SEM).Magnetometer was used to qualify the intensity of magnetism.For the in vitro assay,60 μl solid PLGA-60％ NdFeB-20％ Fe3O4 implant was put in the center of the electromagnetic induction heating coil.Infrared thermal video of the tubes was simultaneously recorded.The size of 2 cm × 2 cm× 2 cm fresh ex vivo bovine liver was prepared,and then 60 μl PLGA-60％ NdFeB-20％ Fe3O4 was injected into it.Similarly,ex vivo bovine liver was heated by the above intermittent time for 1,2,3,4 minutes,respectively,and the ablation volume was calculated.Finally,nude mice were equally divided into treatment group and control group.Mice in treatment group were discontinuously heated for 3 min after being injected with the above mentioned implant,while CEUS was performed before and after heating to observe the blood perfusion in the tumor.One nude mouse was executed on the next day in each group,then pathological sections and HE staining of tumor tissue were taken,whereas the growth of the remaining nude mice were observed daily.Results SEM showed the implant with rough and porous surface.The magnetism increased with the volume of material.The tube and bovine liver experiments showed that the PLGA-60 ％ NdFeB-20％ Fe3O4 generated heat efficiently.The bovine liver ablation experiment showed that the range of ablation of 60 μl PLGA-60 ％ NdFeB-20％ Fe3O4 implant reached (2.34±0.25)cm3 after 3 min heating.In vivo experiments showed that the tumor tissue began to form a scab on the 2nd day,and the scab began to desquamate on the 20th day.CEUS showed the original predominant enhancement disappeared significantly after the treatment.HE staining proved that cancer cells had coagulative necrosis,whereas tumors in control group became bigger.Conclusion PLGA-60％ NdFeB-20％ Fe3O4 in situ implant can produce obvious thermal effect under high frequency alternating magnetic field,therefore can be effectively ablated with nude mice MDA-MB-231 breast cancer during time interval heating.
ABSTRACT
This article briefly summarized conventional k-space technique, partial k-space sampling and key hole technique, then introduced the latest applications during these years.
Subject(s)
Magnetic Resonance ImagingABSTRACT
Through integration of medical imaging resources of 12 community hospitals in the region, a community hospital diagnostic image center was established in 6th hospital. This paper describes the design of the structure and mode of data storage of regional PACS system and the establishment of a database of medical imaging, through which the medical imaging diagnostic level in the community was improved significantly. Through the application of regional PACS system, medical resource was saved and patient treatment facilitated.
Subject(s)
Computer Communication Networks , Information Storage and Retrieval , Methods , Radiology Information Systems , Software DesignABSTRACT
This paper reviews the basic principles and calculation methods of MR specific absorption rate, discusses the clinical application of MR specific absorption rate.
Subject(s)
Humans , Magnetic Resonance Imaging , Radio WavesABSTRACT
This paper introduces general architecture of wireless sensor networks architecture and application in healthcare, discusses the application direction which is urgent need to expand in medical field.
Subject(s)
Telemedicine , Methods , Wireless TechnologyABSTRACT
In this paper, ACR single image method and NEMA dual-image method were measured SNR using two types of phased-array coils. The correlation equation of the two methods was obtained and substitutability of two methods was analyzed. The results showed that the two methods are replaceable in the evaluation of coils, but the later method gets higher SNR than the first method because structure noise is eliminated.
Subject(s)
Algorithms , Magnetic Resonance Imaging , Methods , Signal-To-Noise RatioABSTRACT
Calculation methods of coil sensitivity in parallel MRI were elaborated, compared and analyzed.
Subject(s)
Algorithms , Magnetic Resonance Imaging , MethodsABSTRACT
This paper introduces a new application of PACS in our hospital. Through the integration of PACS, HIS and RIS, digital transformation is made in every step. The functional modules of Body Parts Examined in DICOM is set and good link between PACS and DR is made. So the equipment can retrieval the inspection area automatically and make adjustment on the parameters correspondingly. It makes the workflow optimized and improves the efficiency greatly.
Subject(s)
Electronic Data Processing , Methods , Radiology Information SystemsABSTRACT
In this paper, signal-to-noise ratio (SNR) and signal different-to-noise ratio (SDNR) methods were used to compare image quality using two different radiofrequency coils. The two coil types included an eight-element phased-array coil and a quadrature birdcage head coil with endcap and the comparison studies performed on a uniform cylindrical phantom and volunteer respectively. The results showed phased-array coil have advantages and proved effectiveness of the method in the evaluation and selection of coils.
Subject(s)
Adult , Humans , Male , Cerebral Angiography , Methods , Magnetic Resonance Angiography , Methods , Signal-To-Noise RatioABSTRACT
In this paper, an overview is given on the optimization methods of designing RF coil array. Advantages and disadvantages are also discussed.