Percutaneous Transhepatic Biopsy for Extrahepatic Lesions

Purpose The purpose was to assess the diagnostic accuracy and safety of percutaneous transhepatic biopsy for extrahepatic lesions. Materials and Methods Between January 2008 and December 2019, 26 patients (17 men and 9 women; median age, 60 years) underwent percutaneous transhepatic needle biopsy for extrahepatic lesions at our institution. Transhepatic biopsy was deemed appropriate compared with other biopsy routes or methods (i.e., endoscopic or surgical). The lesions were in the porta hepatis (n = 9), retroperitoneum (n = 6), right adrenal gland (n = 4), right kidney (n = 3), lesser omentum (n = 2), duodenum (n = 1), pleura (n = 1), and inferior vena cava (n = 1). The median maximal diameter of the lesions was 45.5 mm (range, 18–148 mm). Core-needle biopsy was performed in all patients. Eighteen-gauge and 21-G needles were used in 25 and one patient, respectively. Ultrasound was used for biopsy in 21 patients, and CT fluoroscopy was used in five patients. Postbiopsy tract embolization was performed in three patients. Technical success and diagnostic accuracy of the biopsy were evaluated. Complications were recorded using the systemic inflammation response (SIR) criteria. Results The pathological results of biopsy were carcinoma (n = 10), lymphoma (n = 9), and other diagnoses (n = 7). Technical success was obtained in all patients. The accurate diagnosis was achieved in 24 of the 26 patients (92.3%). A major complication, a bladder tamponade, was observed in one patient (3.8%) after biopsy of a right kidney lesion. A hematoma caused by iatrogenic renal injury likely obstructed the bladder outlet. Minor complications were observed in three patients (11.5%). Conclusions Percutaneous transhepatic biopsy for extrahepatic lesions is feasible with acceptable safety

Application of Terahertz Spectroscopy to Rubber Products: Evaluation of Vulcanization and Silica Macro Dispersion

Industrial applications of terahertz (THz) technology are becoming more widespread. In particular, novel evaluation methods for essential rubber products are being developed. THz absorbance spectra of various rubber polymers and reagents enable visualization of filler dispersions and vulcanization reactions. Here, improved visualization of the vulcanization reaction in thick rubber samples is discussed. Silica macro-dispersion is also analyzed because it is a general filler in automobile tires and has been difficult to evaluate with conventional techniques

Feasibility of thin-slice abdominal CT in overweight patients using a vendor neutral image-based denoising algorithm: Assessment of image noise, contrast, and quality.

The purpose of this study was to investigate whether the novel image-based noise reduction software (NRS) improves image quality, and to assess the feasibility of using this software in combination with hybrid iterative reconstruction (IR) in image quality on thin-slice abdominal CT. In this retrospective study, 54 patients who underwent dynamic liver CT between April and July 2017 and had a body mass index higher than 25 kg/m2 were included. Three image sets of each patient were reconstructed as follows: hybrid IR images with 1-mm slice thickness (group A), hybrid IR images with 5-mm slice thickness (group B), and hybrid IR images with 1-mm slice thickness denoised using NRS (group C). The mean image noise and contrast-to-noise ratio relative to the muscle of the aorta and liver were assessed. Subjective image quality was evaluated by two radiologists for sharpness, noise, contrast, and overall quality using 5-point scales. The mean image noise was significantly lower in group C than in group A (p < 0.01), but no significant difference was observed between groups B and C. The contrast-to-noise ratio was significantly higher in group C than in group A (p < 0.01 and p = 0.01, respectively). Subjective image quality was also significantly higher in group C than in group A (p < 0.01), in terms of noise and overall quality, but not in terms of sharpness and contrast (p = 0.65 and 0.07, respectively). The contrast of images in group C was greater than that in group A, but this difference was not significant. Compared with hybrid IR alone, the novel NRS combined with a hybrid IR could result in significant noise reduction without sacrificing image quality on CT. This combined approach will likely be particularly useful for thin-slice abdominal CT examinations of overweight patients