ABSTRACT
The study was taken to assess the feasibility of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) mapping using different b-values for magnetic resonance-guided focused ultrasound (MRgFUS) treatment of uterine fibroid and adenomyoma. The contrast-enhanced T1-weighted image (cT1WI) as well as DWIs and ADC maps of different b-values (i.e. 200, 600 and 800 s/mm2) were obtained from nine fibroid and five adenomyoma patients, immediately after, and 12 months after MRgFUS treatment. The image contrast score, non-perfused volume (NPV) and NPV ratio obtained were compared to determine the feasibility of DWI and ADC mapping for MRgFUS treatment outcome evaluation. Our finding showed thatimmediately after MRgFUS treatment, the DWI acquired using 200 s/mm2 b-value gave the highest image contrast score among all other b-values. The NPV calculated from DWI of 200 s/mm2 showed the best correlation (R2 = 0.938) with post-contrast NPV. At 12 months follow-up, there was no specific b-value considered as significantly superior to others in terms of image contrast. However, the NPVs and NPV ratios obtained from all DWIs and ADC maps of different b-values were in good agreement with the post-contrast NPV and NPV ratio. We observed that the DWI, particularly obtained with a low b-value (i.e. 200 s/mm2), is feasible for delineation and quantitative volumetric evaluation of the ablated region immediately after the MRgFUS treatment. At 12 months follow-up, both DWIs and ADC maps are feasible for NPV and NPV ratio calculation.
ABSTRACT
In the current study, we report a new technique to place a tunnelled peripherally inserted central catheter (PICC) at the upper arm of patient under real-time ultrasound-guided venipuncture using disposal equipment provided within a standard PICC set. The tunnelling of the PICC required an extra time of 5 minutes but was well tolerated by all patients involved in the study. The tunnelled PICC was applied on 50 patients and the infection rate as well its catheter dwell time were compared to another 50 patients with conventional PICC. The rate of patients who developed infection decreased from 34% for conventional PICC to 16% in tunnelled PICC patients. The central line-associated blood stream infections rate was also decreased from 4.4 per 1000 catheter-days for conventional PICC to 1.3 per 1000 catheter-days for tunnelled PICC. The mean time to infection development for tunnelled PICC (24 days) was longer than those observed with conventional PICC (19 days). Tunnelled PICC has also increased the mean catheter dwell time from 27 days (for conventional PICC) to 47 days. Tunnelling a PICC has the potential to reduce the infection rate while increase the catheter dwell time.