Percutaneous Vertebroplasty: Preliminary Experiences with Rotational Acquisitions and 3D Reconstructions for Therapy Control

Percutaneous vertebroplasty (PVP) is carried out under fluoroscopic control in most centers. The exclusion of implant leakage and the assessment of implant distribution might be difficult to assess based on two-dimensional radiographic projection images only. We evaluated the feasibility of performing a follow-up examination after PVP with rotational acquisitions and volumetric reconstructions in the angio suite. Twenty consecutive patients underwent standard PVP procedures under fluoroscopic control. Immediate postprocedure evaluation of the implant distribution in the angio suite (BV 3000; Philips, The Netherlands) was performed using rotational acquisitions (typical parameters for the image acquisition included a 17-cm field-of-view, 200 acquired images for a total angular range of 180°). Postprocessing of acquired volumetric datasets included multiplanar reconstruction (MPR), maximum intensity projection (MIP), and volume rendering technique (VRT) images that were displayed as two-dimensional slabs or as entire three-dimensional volumes. Image evaluation included lesion and implant assessment with special attention given to implant leakage. Findings from rotational acquisitions were compared to findings from postinterventional CT. The time to perform and to postprocess the rotational acquisitions was in all cases less then 10 min. Assessment of implant distribution after PVP using rotational image acquisition methods and volumetric reconstructions was possible in all patients. Cement distribution and potential leakage sites were visualized best on MIP images presented as slabs. From a total of 33 detected leakages with CT, 30 could be correctly detected by rotational image acquisition. Rotational image acquisitions and volumetric reconstruction methods provided a fast method to control radiographically the result of PVP in our case

High-resolution 3D X-ray imaging of intracranial nitinol stents

Introduction To assess an optimized 3D imaging protocol for intracranial nitinol stents in 3D C-arm flat detector imaging. For this purpose, an image quality simulation and an in vitro study was carried out. Methods Nitinol stents of various brands were placed inside an anthropomorphic head phantom, using iodine contrast. Experiments with objects were preceded by image quality and dose simulations. We varied X-ray imaging parameters in a commercially interventional X-ray system to set 3D image quality in the contrast–noise–sharpness space. Beam quality was varied to evaluate contrast of the stents while keeping absorbed dose below recommended values. Two detector formats were used, paired with an appropriate pixel size and X-ray focus size. Zoomed reconstructions were carried out and snapshot images acquired. High contrast spatial resolution was assessed with a CT phantom. Results We found an optimal protocol for imaging intracranial nitinol stents. Contrast resolution was optimized for nickel–titanium-containing stents. A high spatial resolution larger than 2.1 lp/mm allows struts to be visualized. We obtained images of stents of various brands and a representative set of images is shown. Independent of the make, struts can be imaged with virtually continuous strokes. Measured absorbed doses are shown to be lower than 50 mGy Computed Tomography Dose Index (CTDI). Conclusion By balancing the modulation transfer of the imaging components and tuning the high-contrast imaging capabilities, we have shown that thin nitinol stent wires can be reconstructed with high contrast-to-noise ratio and good detail, while keeping radiation doses within recommended values. Experimental results compare well with imaging simulations

Fused magnetic resonance angiography and 2D fluoroscopic visualization for endovascular intracranial neuronavigation Technical note

Advanced transluminal neurovascular navigation is an indispensable image-guided method that allows for real-time navigation of endovascular material in critical neurovascular settings. Thus far, it has been primarily based on 2D and 3D angiography, burdening the patient with a relatively high level of iodinated contrast. However, in the patients with renal insufficiency, this method is no longer tolerable due to the contrast load. The authors present a novel image guidance technique based on periprocedural fluoroscopic images fused with a preinterventionally acquired MRI data set. The technique is illustrated in a case in which the fused image combination was used for endovascular treatment of a giant cerebral aneurysm. (http://thejns.org/doi/abs/10.3171/2012.11.JNS111355

Silhouette fusion of vascular and anatomical volume data

In this paper we present a novel method for the combined hybrid visualization of the cerebral blood vessels, segmented from a 3D rotational angiography dataset, and datasets containing the soft tissue anatomy, such as CT or MR. This visualization method is targeted at the use in interventional treatment of vascular pathologies and endovascular treatment of the neoplastic tissue. Our method distinguishes itself since it offers the possibility to provide the clinician with a maximum amount of contextual information about the spatial relationship and topology of both datasets, without compromising the ease of use and interpretation. Further it is discussed how an interactive visualization can be implemented on off-the-shelf graphics hardware, and it is indicated which clinical benefits can be achieved. © 2006 IEEE.IEEE international symposium on biomedical imaging : from nano to macro, ISBI-2006, pp. 121-124, April 6-9, 2006, Arlington, Virginia, USAstatus: publishe

Determining tissue surrounding an object being inserted into a patient

It is described a method for determining and assessing the tissue surrounding an object being inserted into a patient. The method comprises acquiring a first dataset representing a first 3D image of the patient, acquiring a second dataset representing a second 3D image of the blood vessel structure of the patient and acquiring a third dataset representing a 2D image of the patient including the object. The method further comprises recognizing the object within the 2D image, registering two of the three datasets with each other, whereby the object is back-projected in the blood vessel structure, in order to generate a first combined dataset, and registering the first combined dataset with the remaining dataset in order to generate a second combined dataset representing a further image surrounding the object. The method allows for combining diagnostic scanning such as CT, 3D RA and real-time 2D fluoroscopy. Thereby, it is possible to generate an image perpendicular to a catheter tip representing the object being inserted into the patient. Since the 3D-RA displays the lumen and the diagnostic scanning displays soft-tissue, it is possible to assess the tissue at the catheter tip position.</p

Utility of VasoCT in the treatment of intracranial aneurysm with flow-diverter stents

Object. The small size and tortuous anatomy of intracranial arteries require that flow-diverter stents in the intracranial vasculature have a low profile, high flexibility, and excellent trackability. However, these features limit the degree of radiopacity that can be incorporated into the stents. Visualization of these stents and the degree of stent deployment using conventional radiographic techniques is suboptimal. To overcome this drawback, the authors used a new combined angiography/CT suite that uses flat-panel detector technology for higher resolution angiography

Utility of VasoCT in the treatment of intracranial aneurysm with flow-diverter stents Clinical article

Object. The small size and tortuous anatomy of intracranial arteries require that flow-diverter stents in the intracranial vasculature have a low profile, high flexibility, and excellent trackability. However, these features limit the degree of radiopacity that can be incorporated into the stents. Visualization of these stents and the degree of stent deployment using conventional radiographic techniques is suboptimal. To overcome this drawback, the authors used a new combined angiography/CT suite that uses flat-panel detector technology for higher resolution angiography