Prosthetic vascular graft rupture caused by claw-type rib fixation strut: a case report.

A 66-year-old-man who had undergone partial aortic arch and descending aortic graft replacement for a dissecting aortic aneurysm presented to our hospital with pain and beating swelling of his left back shoulder. Enhanced computed tomography and aortic angiography revealed graft rupture caused by one of the claws of a rib fixation strut. Furthermore, another claw had invaded a lung. We performed emergency thoracic endovascular aortic repair, and removed all of the struts 3 weeks later. Claw-type rib fixation struts have the potential to injure other organs, including prosthetic grafts. Careful follow-up is mandatory after implantation of this type of strut.

Value of diffusion tensor imaging in differentiating malignant from benign parotid gland tumors.

PURPOSE: To evaluate whether diffusion tensor imaging (DTI) can be used to differentiate malignant parotid gland tumors from the benign ones. MATERIALS AND METHODS: The study population comprised 59 parotid gland tumors (24 Warthin's tumors, 19 pleomorphic adenomas, seven other benign tumors, and nine malignant tumors). Single-shot echo-planar DTI was performed with motion-probing gradients along 30 noncollinear directions (b=1000s/mm2) at 3.0T. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values for benign and malignant tumors were compared using the Mann-Whitney U test. Receiver-operating characteristic (ROC) curve analysis was performed to assess the ability of the ADC and FA values to differentiate malignant tumors from the benign ones. RESULTS: ADC values showed no significant difference between malignant (0.93±0.21×10-3mm2/s) and benign tumors (1.19±0.50×10-3mm2/s) (p=0.225). FA values of malignant tumors were significantly higher than those of benign tumors (0.26±0.06 vs. 0.17±0.05, p<0.001). The area under the ROC curve of FA was significantly greater than that under the curve of ADC (0.884 vs. 0.628, p=0.010). CONCLUSIONS: DTI, particularly FA, can help differentiate malignant parotid gland tumors from the benign ones.

Histogram Analysis of Apparent Diffusion Coefficient in Differentiating Pancreatic Adenocarcinoma and Neuroendocrine Tumor.

The aim of this study was to investigate whether histogram analysis in diffusion-weighted (DW) magnetic resonance imaging (MRI) can help differentiate pancreatic adenocarcinomas from neuroendocrine tumors.Sixty-four patients with histologically confirmed 53 pancreatic adenocarcinomas or 19 neuroendocrine tumors underwent DW MRI. We evaluated the pixel distribution histogram parameters (mean, skewness, kurtosis, and entropy) of the apparent diffusion coefficient (ADC) values derived from b-values of 0 and 200 (ADC200), 0 and 400 (ADC400), or 0 and 800 (ADC800) s/mm(2). Histogram parameters were compared between pancreatic adenocarcinomas and neuroendocrine tumors, and the diagnostic performance was evaluated by using receiver operating characteristic (ROC) analysis.The mean ADC200 and ADC400 were significantly higher in neuroendocrine tumors than in pancreatic adenocarcinomas (P = 0.001 and P = 0.019, respectively). Pancreatic adenocarcinomas showed significantly higher skewness and kurtosis on ADC400 (P = 0.007 and P = 0.001, respectively) and ADC800 (P = 0.001 and P = 0.001, respectively). With all b-value combinations, the entropy of ADC values was significantly higher in pancreatic adenocarcinomas (P < 0.001 for ADC200; P = 0.001 for ADC400; P < 0.001 for ADC800), and showed the highest area under the ROC curve for diagnosing adenocarcinomas (0.77 for ADC200, 0.76 for ADC400, and 0.78 for ADC800).ADC histogram analysis of DW MRI can help differentiate pancreatic adenocarcinomas from neuroendocrine tumors.

External-beam radiation therapy for age-related macular degeneration: two years' follow-up results at a total dose of 20 Gy in 10 fractions.

PURPOSE: The efficacy of external-beam radiation therapy (RT) was evaluated in the treatment of eyes with subfoveal or juxtafoveal choroidal neovascularization in age-related macular degeneration (ARMD). MATERIALS AND METHODS: Twenty-one eyes of 18 patients with occult or mixed-type ARMD received a total dose of 20 Gy of 6 MV X-rays in 10 fractions. The follow-up time was 24 months. Fifteen non-treated eyes of 13 patients who had been followed served as a control. RESULTS: In the RT group, visual acuity was improved in three eyes, maintained in 14 eyes, and worsened in four eyes. In the control group, it was not improved in any eyes, was maintained in six eyes, and worsened in nine eyes. The improved or maintained rate in visual acuity was 81% in the RT group and 40% in the control group (p=0.0342). In the RT group, fundoscopic and angiographic findings were improved in five eyes, unchanged in seven eyes, and worsened in nine eyes, while they were not improved in any eyes, unchanged in two eyes, and worsened in 13 eyes in the control group(p=0.0342). CONCLUSION: RT at a total dose of 20 Gy in 10 fractions is effective for ARMD for at least two years. RT may be effective treatment for occult or mixed-type ARMD compared with the classic type.