Abstract. Computed tomography (CT)-guided lung biopsy is a well-established diagnostic method for pulmonary lesions. However, the use of this technique often results in pneumothorax development. The aim of the present study was to evaluate the association between biopsy needle angle and pneumothorax development associated with computed tomography-guided lung biopsy. We retrospectively analyzed the results of CT-guided lung biopsies for 325 cases to investigate physical risk factors for pneumothorax development. Biopsy needle angle and patient positioning were included in the analysis. Pneumothorax occurred in 160 of 325 procedures (49.2%). Discontinuation of the procedure as a result of pneumothorax occurred in 18 of 160 procedures (11.2%). Upper lung lobe pneumothorax occurred in 40.8% (58/142), middle lobe in 17.6% (25/142), and lower lobe pneumothorax occurred in 41.5% (59/142) of these procedures. Discontinuation of the procedure occurred in 2.5% of the upper lobe (4/160), 0.6% of the middle lobe (1/160), and 8.1% of the lower lobe (13/160) biopsies. Mild pneumothorax occurred in 59.4% (95/160), moderate in 25.0% (40/160), and severe in 7.5% (12/160) of the affected cases, and biopsy was discontinued in 11.2% (18/160) of the affected cases. When the needle angle was <90˚, 40.3% (131/325) of the patients experienced no pneumothorax development, 40.0% (130/325) developed pneumothorax, and 4.3% (14/325) of the procedures were discontinued. The results showed that use of CT-guided lung biopsy can reduce the rate of pneumothorax development that occurs when other procedures are used. The access route is simple and easy to puncture, and proper use of breath holding reduces diaphragmatic movement.

ObjectiveSimilar to perfusion studies after acute ischemic stroke, measuring cerebral blood volume (CBV) via C-arm computed tomography before and after therapeutic interventions may help gauge subsequent revascularization. We tested serial dilutions of intra-arterial injectable contrast medium (CM) to determine the optimal CM concentration for quantifying parenchymal blood volume by flat-panel detector imaging (FD-PBV).MethodsCM was diluted via saline power injector, instituting time delays for FD-PBV studies. A red/green/blue (RGB) color scale was employed to quantify/compare FD-PBV and magnetic resonance-derived CBV (MRCBV).ResultsContrast values of right and left common carotid arteries did not differ significantly at CM dilutions of ≥20%. RGB analysis of FD-PBV imaging (relative to MR-CVB), showed CM dilution altered the colors (by 16%), increasing red and decreasing blue ratios.ConclusionDiluting CM to 20% resulted in no laterality differential of FD-PBV imaging, with left/right quantitative ratios approaching 1.1 (optimal for clinical use).

For stent-assisted coil embolization, quantitative assessment of conebeam CT showed that 10 second/1 × 1 was equivalent to 20 second/2 × 2 for imaging deployed intracranial stents. Furthermore, the 10-second/1 × 1 settings resulted in a much smaller DAP.

Purpose Flat panel detector (FD)-equipped angiography machines are increasingly used for neuro-angiographic imaging. During intracranial stent-assisted coil embolization procedures, it is very important to clearly and quickly visualize stent shape after deployment in the vessel. It is necessary to quickly visualize stents by cone-beam computed tomography (CBCT). The aim of this study was to compare CBCTs at 10 and 20 s, and to confirm that this method is useful for neuro-endovascular treatment procedures. Materials and methods We treated 30 patients with wide-necked intracranial aneurysms with a flexible, self-expanding neurovascular stent and subsequent aneurysm embolization with platinum micro-coils. We performed the CBCT after stent deployment. We compared the 10 s and 20 s CBCTs, using the full width one-half maximum (FWHM) visualization. Results Accurate stent placement with subsequent coil occlusion of the aneurysms was feasible in all patients. Stent struts were clearly visualized on both 10 s and 20 s CBCTs. Importantly, 10 s CBCT can reduce the radiation dose by about 42%, compared with 20 s CBCT. Performing 10 s CBCT with a 14% dilution of the contrast medium may significantly improve image acquisition during stent-assisted coil embolization. Conclusions Reduced-dose, 10 s CBCT can visualize stents in clinical cases, while significantly reducing radiation exposure.

We compared the accuracy in evaluating an unrapture aneurysm between NV and 3D-DSA. In vitro, we evaluated the accuracy in calculating the volume of the Aneurysm model. We compared the diameter of the first coil and estimated the diameter of the Aneurysm. The Aneurysm size calculated by NV resembled the first coil more than the size measured by 3D-DSA. In clinical cases, the measurement of NV is objective; the measurement of 3D-DSA, however, is subjective by person. NV has an automatic measurement that is useful for clinical cases.