Experimental Research Of Chemical-shift MR Imaging Monitor MR-guided Percutaneous Chemical Ablation For VX2

Objective:Liver cancer is very common and a significant cause of mortality and morbidity in china. Although, in many cases, surgical resection or transplantation offers the only chance for cure, most patients with HCC are not candidates for these treatments. Recently, several minimally invasive, nonsurgical local therapies have been described. These include embolization therapy, radiofrequency ablation, laser-induced thermotherapy, and chemical ablation with use of ethanol or acetic acid. When performed for small ( 3 cm) HCC, chemical ablation can achieve 5-year survival rates of 60%, equivalent to those of surgical resection. A recent randomized, controlled trial suggested that acetic acid ablation is more effective than ethanol ablation in patients with HCC smaller than 3 cm. But, the kidney toxicity of Acetic acid has restricted its application. ethanol ablation has been regarded highly by people ,got the universally accepted consistent curative effect.the side effect is more small relatively.Chemical ablation has most commonly been performed with use of either ultrasound or computed tomographic guidance. Unfortunately, these modalities do not allow for direct visualization of the chemical agents being injected. Instead, the volume to be injected is determined based on the morphology and size of the lesion.Methods:1 Tumor implantation of a solid vx2 tumor in the liver was carried out in New Zealand white rabbits. These rabbits was placed in a 10-cm birdcage transmit/receive coil on a 1.5-T MR imaging system. Transverse images of these rabbits were then acquired with use of a two-dimensional, SE T1WI,FSPGR T1WI,FRFSE T2WI, Confirm a tumour cultivating success. Puts 2 rabbits to death after scanning, is used for pathological examination. The spare VX2 tumors rabbits were performed with percutaneous chemical ablation.2 MRI-guided technology FRFSE is use as guarding a means. Carry out the fixing position and the puncture on a 1.5-T MR scanner. Control the direction and depth of puncture needle with MR scanner. demonstrates puncture needle point in lesion and performs PEI.3 Chemical-shift MR Imaging VX2 tumors were carried out in these rabbits. Chemical-shift MR imaging was performed in Phantom and VX2 tumors of rabbits during PEI with FRFSE T2WI on a 1.5-T MR scanner.Images of the phantom were generated with the spectrometer frequency centered on the acetate resonance determined to be shifted -240Hz (or -170 Hz)from the water resonance. The offset frequency of the chemical shift suppression pulse was set at 240 Hz.Result:1 Focal signal increases varies in T2-Weighted imaging after PEI at the site of injection. The study revealed there was significant positive in radiologic-pathologic correlation.2 Phantom data demonstrated focal increases in the observed signal in chemical-shift MR imaging that correlate well with the site of injection. The study in a hepatic VX2 tumor of rabbits revealed focal signal at the injection site. There is significant positive in the radiologic-pathologic correlation.3 Focal increases in the observed signal in chemical-shift MR imaging that correlate well with the site of injection. The study in hepatic VX2 tumors of rabbits revealed focal signal at the injection site. There is significant positive in the radiologic-pathologic correlation.4 Focal signal increases in chemical-shift MR imaging and varies in T2-Weighted imaging after PEI at the site of injection. The study revealed there were significant differences in lesion-to-liver contrast-to-noise ratios on chemical-shift MR imaging and T2-weighted imaging and both positive radiologic-pathologic correlation.Conclusions:1 Ethanol distribution may be preliminarily monitored with T2-weight imaging during PEI.2 Chemical-shift MR imaging may be used to Acetic Acid visualize distribution during percutaneous chemical ablation procedures3 chemical-shift MR imaging may be used to visualize ethanol distribution during PEI. 4 Ethanol distribution may be more accurately monitored with Chemical-shift MR imaging than with T2-weight imaging during PEI.