(18)F-FDG PET is considered to be useful for the diagnosis and evaluation of disease activity along with HRCT findings, and in monitoring response to chemotherapy in patients with PM.

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18 F-FDG PET is increasingly used for lung cancer; however, some insufficient results have been reported. The purpose of this study was to evaluate the efficacy of dual-time-point 18 F-FDG PET for staging lung cancer and for differentiating metastatic from nonmetastatic lung cancer lesions. Methods: One hundred fifty-five lung cancer patients with known or suspected mediastinal and hilar lymph node involvement or distant metastases underwent whole-body 18 F-FDG PET at 2 time points: scan 1 at 60 min (early imaging) and scan 2 at 180 min (delayed imaging) after 18 F-FDG injection. 18 F-FDG PET findings of nodal and distant metastases were evaluated using conventional imaging, clinical follow-up findings, and the results of autopsy or biopsy. Results: A total of 580 lesions (155 primary lesions, 315 metastatic lesions, and 110 nonmetastatic lesions) were used for analysis. A closer correlation between the primary lesions and metastases was observed for the retention index (RI) standardized uptake value (SUV) than for early and delayed SUV. There was no relationship between the RI SUV results of primary lesions and those of nonmetastatic lesions. The RI SUV of metastatic lesions was approximately 0.5-2 times the RI SUV of primary tumors. We found that the accuracy of 18 F-FDG PET was improved when RI SUV was used for detecting lymph node and distant metastases, because of the significant improvement in specificity relative to early and delayed SUV. Conclusion: RI SUV raised the accuracy for diagnosis of metastases and was superior to early and delayed imaging in terms of differentiating malignancy from nonmetastatic uptake.

BackgroundA low-profile visualized intraluminal support (LVIS) device may incompletely expand during stent deployment in tortuous vessels. However, the cause of incomplete expansion remains uninvestigated. We aimed to examine in vitro the factors causing incomplete expansion in LVIS deployment by using various vessel models.MethodsA linear model group was created by connecting linear silicone tubes (inner diameter 4 mm) at both sides of the LVIS deployment vessel (inner diameter 4 mm) with different curvature angles of 10–140° at 10° intervals. For comparison, proximal and distal bending model groups were created, both with 90° bending on the proximal/distal larger curvature side of the deployment vessel. A single operator macroscopically deployed an LVIS (4.5×32 mm) four times in each model and 56 times in each group.ResultsIn each model group the LVIS deployment vessel with a narrow curvature angle incompletely expanded. Incomplete expansion occurred significantly more frequently in the distal bending model group (34%, 19/56) compared with that in the linear model group (14.3%, 8/56; p<0.001), as well as in the proximal bending model group (59%, 33/56) compared with that in the distal bending model group (p<0.05). Compared with the linear model group, the proximal bending model group had a significantly reduced angle between the LVIS and the direction of the LVIS pushing force, but no significant change was found in the distal bending model group compared with that in the linear model group.ConclusionsFactors such as acute angle, distal bending, and proximal bending of the deployment vessel can cause incomplete LVIS expansion.

Objective: Vac-Lok cushions are widely used in the field of radiation therapy to fix a body in place. We introduced this device during neuroendovascular therapy and evaluated its utility in comparison with a conventional device. Methods:We conducted questionnaire surveys regarding post-procedural headache among patients and regarding advantages and disadvantages of the new fixation device among radiation technologists and neurosurgeons. We measured the contact pressures of volunteers' heads to compare stress on the head between the two devices.Results: Contact pressure significantly decreased using the new device. Furthermore, complaints regarding post-procedural headache sharply declined after introducing the new device. The new device also reduces respiratory motion artifacts and allows the head to be positioned at any angle we want. Conclusion:The Vac-Lok cushion is extremely useful for fixing the head in place during neuroendovascular therapy.