High-quality 3D Reconstruction Research Articles

Three-dimensional renal CT angiography for guiding segmental renal artery clamping during laparoscopic partial nephrectomy

To evaluate the effectiveness of three-dimensional (3D) renal computed tomography angiography (CTA) in guiding segmental renal artery clamping during laparoscopic partial nephrectomy (LPN). Forty-three patients with renal tumours undergoing renal CTA before LPN were retrospectively enrolled in this study. 3D arteriogram reconstructed images were created to identify the renal tumour-supplying arteries. The number and location of these targeted vessels were annotated on 3D images preoperatively and compared with the clamped vessels during LPN. The consistency between target vessels annotated at CTA and clamped arteries at LPN was compared both using a patient-based analysis and vessel-based analysis. The χ(2) test was applied to analyse the influence of tumour size, location, and growth pattern on the number of clamped segmental renal branches. On patient-based analysis, the number of targeted vessels was consistent with the clamped vessels during LPN in 33 of 43 patients. On vessel-based analysis, 56 of 65 target vessels annotated at CTA were clamped during LPN. More segmental renal branches (p=0.04) were clamped in patients with tumours of larger size. Tumour location and growth pattern had no association with the number of clamped segmental branches during LPN. High-quality CTA images and 3D reconstruction images can detect detailed information of tumour-supplying arteries to renal tumours. 3D renal CTA is an effective way to guide segmental renal artery clamping during LPN.

3D passive integral imaging using compressive sensing

Passive 3D sensing using integral imaging techniques has been well studied in the literature. It has been shown that a scene can be reconstructed at various depths using several 2D elemental images. This provides the ability to reconstruct objects in the presence of occlusions, and passively estimate their 3D profile. However, high resolution 2D elemental images are required for high quality 3D reconstruction. Compressive Sensing (CS) provides a way to dramatically reduce the amount of data that needs to be collected to form the elemental images, which in turn can reduce the storage and bandwidth requirements. In this paper, we explore the effects of CS in acquisition of the elemental images, and ultimately on passive 3D scene reconstruction and object recognition. Our experiments show that the performance of passive 3D sensing systems remains robust even when elemental images are recovered from very few compressive measurements.

Touchless gesture user interface for interactive image visualization in urological surgery

In the operating room (OR) a touchless interface is an ideal solution since it does not demand any physical contact and still can provide the necessary control features in a cleansed and sterilized environment. Using open-source software libraries and image processing techniques, we implemented a hand tracking and gesture recognition system based on the Kinect device that enables surgeon to successfully touchlessly navigate through the image in the intraoperative setting through a personal computer. We used the InVesalius software, which provides high-quality 3D reconstruction of medical images. Computed tomography data were intraoperatively fruitfully accessed through a simple and cheap solution in 4 tumor enucleations in 3 male patients in whom elective nephron-sparing surgeries were performed for small non-exophitic tumors. Mean tumor length was 2.7 cm (2.1, 2.7, 2.9 and 3.1 cm), and real-time ultrasound was not necessary for intraoperative identification in 3 of 4 endorenal tumors. All pathological reports revealed renal cell carcinoma, Fuhrman grade I, and negative inked surgical margins. No intra- or postoperative complication was reported. For the first time in the literature, a touchless user interface solution applying the Kinect device showed to be very efficient and enabled a low-cost and accurate control of the software InVesalius intraoperative, just using hand gestures. It can be used with any mouse-controlled software, opening an avenue for potential applications in many other areas, such as data visualization, augmented reality, accessibility, and robotics. The further validation and advancement of this technology are underway.

1515 TOUCHLESS GESTURE USER INTERFACE FOR INTERACTIVE IMAGE VISUALIZATION IN UROLOGICAL SURGERY

You have accessJournal of UrologyTechnology & Instruments: Surgical Education & Skills Assessment/Ureteroscopy II1 Apr 20121515 TOUCHLESS GESTURE USER INTERFACE FOR INTERACTIVE IMAGE VISUALIZATION IN UROLOGICAL SURGERY Guilherme Ruppert, Leonardo Reis, Paulo Amorim, Tiago Moraes, and Jorge Silva Guilherme RuppertGuilherme Ruppert Campinas, Brazil More articles by this author , Leonardo ReisLeonardo Reis Campinas, Brazil More articles by this author , Paulo AmorimPaulo Amorim Campinas, Brazil More articles by this author , Tiago MoraesTiago Moraes Campinas, Brazil More articles by this author , and Jorge SilvaJorge Silva Campinas, Brazil More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.1282AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES In the operating room a touchless interface is an ideal solution since it does not demand any physical contact and still can provide the necessary control features in a cleansed and sterilized environment. METHODS Using open-source software libraries and image processing techniques, we implemented a hand tracking and gesture recognition system based on the Kinect device that enables surgeon to successfully navigate through the image in the intraoperative setting. We used the InVesalius software, which provides high-quality 3D reconstruction of medical images. The hand of the user is tracked and the corresponding position is used to move the mouse pointer and button clicks events are also virtually generated. RESULTS Nephron-sparing surgery can be facilitated by using intra-operative hand gestures to provide touchless control of 3D medical imaging software. Computed tomography data from patients with renal masses were fruitfully accessed during surgery through a simple and cheap solution. The model was easily transferred to a personal computer, allowing the surgeon to touchlessly navigate through the 3D images in the intraoperative setting. We have utilized the proposed solution in 3 tumor enucleations in 2 male patients in whom elective nephron sparing surgery was performed for small non-exophitic tumors. Mean tumor length was 2.7 cm (2.1, 2.9 and 3.1 cm) and real-time ultrasound was not necessary in 2 tumors. All surgeries were guided by image review through gesture interface during the procedure, allowing anatomical support based on the 3D imaging previously obtained by CT scan. All pathological reports revealed renal cell carcinoma, Furhman grade I, and negative inked surgical margins. CONCLUSIONS The solution was successfully used intraoperative and can be used with any mouse-controlled software. This is an important step in bringing technology to the operating room to assist the surgeon directly, opening an avenue for potential applications in many other areas, such as: data visualization, augmented reality, accessibility and robotics. © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4SApril 2012Page: e613-e614 Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.MetricsAuthor Information Guilherme Ruppert Campinas, Brazil More articles by this author Leonardo Reis Campinas, Brazil More articles by this author Paulo Amorim Campinas, Brazil More articles by this author Tiago Moraes Campinas, Brazil More articles by this author Jorge Silva Campinas, Brazil More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Fijación vertebral posterior guiada por neuronavegación: Experiencia en 121 casos

The authors present the results of a series of 121 cases of posterior vertebral fixation carried out from Sept 2008 to Sept 2010 using Flouro 2D-TC assisted Vector Vision o Kolibri navigator. ( Brain LAB, Feldkirchen, Germany). The sample included 68 males and 53 females. Age range was 24-75 with an average of 50.35., all with indication for instrumentation by different pathologies. Patients presenting vertebral lesions of varying ethiology and lesion level with vertebral posterior fixation indication were included in the study. All underwent a CT before surgery, according to navigation protocol, and the images obtained were merged in the navigator with those obtained in the operating room with a Flouro 2D, which allowed a high quality 3D reconstruction to be performed and thus the capacity to navigate in a real-virtual manner. To evaluate the results of the implant a post-op CT was performed and the position of the implant was defined according to the Heary scale. The calabration time of the material was also evaluated, number of shots with the Flouro-2D, and for clinical evaluation VAS scales were employed, Oswestry and JOA (L), as well as the degree of satisfaction and acceptance of the procedure. A total of 580 screws were implanted, distributed in 62 cervicals of which 24 were in C1-C2, 38 dorsals, 370 lumbar and 110 sacral. Open surgery was performed in 42 cases, MIS in 28 and percutaneous in 51. The presision of the implant was 98.45% with a global deviation of 1.55%, that according to the Heary scale was distributed in grade ll: 2 (1 cervical, 1 lumbar) grade lll: 4 (1 cervical, 2 dorsal, 1 lumbar), grade IV: 3 (1 cervical, 2 lumbar). General average time of calibration per procedure was 2 min. 49 seconds and the mean flouroscopic exposure was one shot at cervical and dorsal and two shots at lumbar level. The clinical evaluation at one month of 121 patients was 8.6/3.0 in the VAS, 68.0% / 23.0% in Oswestry and 6.4/13.1 in JOA (L), with those parameters remaining stable at 3 months in 100 and at 6 months in 87 patients respectively, and the degree of satisfaction between being completely and very satisfied with the procedure was 94.9%, and those who would submit to another treatment was more than 94%. Navigation with Flouro-2D-CT is a high precision technique that reduces complications of varying severity according to the level operated well as number of reinterventions, radiation exposure and surgical time.

3D Microstructural characterization of a solid oxide fuel cell anode reconstructed by focused ion beam tomography

The three-dimensional microstructure of an SOFC anode has been characterized using a focused ion beam-scanning electron microscope. The sample preparation and the experimental milling and imaging parameters have been optimized in order to obtain a high-quality 3D reconstruction. Volume fractions and the volumetric connectivity of the individual phases, specific surface and interface areas and the three-phase boundary length have been estimated. Effective thermal, electronic and ionic conductivities of the sample as well as the tortuosity of the solid phases have been evaluated by solving the diffusive transport equation with an implicit 3D finite difference method.

Clinical Feasibility of a Fully Automated 3D Reconstruction of Rotational Coronary X-Ray Angiograms

Although fixed view x-ray angiography remains the primary technique for anatomic imaging of coronary artery disease, the known shortcomings of 2D projection imaging may limit accurate 3D vessel and lesion definition and characterization. A recently developed method to create 3D images of the coronary arteries uses x-ray projection images acquired during a 180 degrees C-arm rotation and continuous contrast injection followed by ECG-gated iterative reconstruction. This method shows promise for providing high-quality 3D reconstructions of the coronary arteries with no user interaction but requires clinical evaluation. The reconstruction strategy was evaluated by comparing the reconstructed 3D volumetric images with the 2D angiographic projection images from the same 23 patients to ascertain overall image quality, lesion visibility, and a comparison of 3D quantitative coronary analysis with 2D quantitative coronary analysis. The majority of the resulting 3D volume images were rated as having high image quality (66%) and provided the physician with additional clinical information such as complete visualization of bifurcations and unobtainable views of the coronary tree. True-positive lesion detection rates were high (90 to 100%), whereas false-positive detection rates were low (0 to 8.1%). Finally, 3D quantitative coronary analysis showed significant similarity with 2D quantitative coronary analysis in terms of lumen diameters and provided vessel segment length free from the errors of foreshortening. Fully automated reconstruction of rotational coronary x-ray angiograms is feasible, produces 3D volumetric images that overcome some of the limitations of standard 2D angiography, and is ready for further implementation and study in the clinical environment.

Adaptive colour classification for structured light systems

The authors present an adaptive colour classification method as well as specialised low-level image processing algorithms. With this approach the authors achieve high-quality 3D reconstructions with a single-shot structured light system without the need of dark laboratory environments. The main focus of the presented work lies in the enhancement of the robustness with respect to environment illumination, colour cross-talk, reflectance characteristics of the scanned face etc. For this purpose the colour classification is made adaptive to the characteristics of the captured image to compensate for such distortions. Further improvements are concerned with enhancing the quality of the resulting 3D models. Therefore the authors replace the typical general-purpose image preprocessing with specialised low-level algorithms performing on raw photo sensor data. The presented system is suitable for generating high-speed scans of moving objects because it relies only on one captured image. Furthermore, due to the adaptive nature of the used colour classifier, it generates high-quality 3D models even under perturbing light conditions.

Dedicated multi-detector CT of the esophagus: spectrum of diseases

Multi-detector computed tomography (CT) offers new opportunities in the imaging of the gastrointestinal tract. Its ability to cover a large volume in a very short scan time, and in a single breath hold with thin collimation and isotropic voxels, allows the imaging of the entire esophagus with high-quality multiplanar reformation and 3D reconstruction. Proper distention of the esophagus and stomach (by oral administration of effervescent granules and water) and optimally timed administration of intravenous contrast material are required to detect and characterize disease. In contrast to endoscopy and double-contrast studies of the upper GI tract, CT provides information about both the esophageal wall and the extramural extent of disease. Preoperative staging of esophageal carcinoma appears to be the main indication for MDCT. In addition, MDCT allows detection of other esophageal malignancies, such as lymphoma and benign esophageal tumors, such as leiomyma. A diagnosis of rupture or fistula of the esophagus can be firmly established using MDCT. Furthermore, miscellaneous esophageal conditions, such as achalasia, esophagitis, diverticula, and varices, are incidental findings and can also be visualized with hydro-multi-detector CT. Multi-detector CT is a valuable tool for the evaluation of esophageal wall disease and serves as an adjunct to endoscopy.

Detection and characterization of benign focal liver lesions with multislice CT

MDCT is a rapidly evolving technique that significantly improves CT imaging for several indications including depiction of focal benign lesions. Imaging mainly profits from improved longitudinal spatial resolution allowing high-quality non-axial reformations and 3D reconstructions and CT angiography as well as rapid accurate multiphase imaging with short breath-holding periods. This review provides an overview of the current status of MDCT with respect to liver imaging and the implications for characterizing benign focal liver lesions. MDCT currently allows the acquisition of thin slices in daily routine diagnostics providing an improved detection rate of small liver lesions. Whereas large benign focal liver lesions exhibit typical patterns of morphology, attenuation and perfusion, which also may be assessed with single-slice scanners, small lesions remain challenging even with MDCT, since the specific criteria for confident diagnosis become more ambiguous. Here, MR imaging provides more detailed information about tissue components and the availability of liver-specific contrast agents, adding further impact to this technique. With respect to dose considerations, the number of necessary multiphase scans as well as the application of very thin collimation should be strictly checked for each patient undergoing MDCT based on the individual clinical situation and question.

A High-Accuracy Passive 3D Measurement System Using Phase-Based Image Matching

This paper presents a high-accuracy 3D (three-dimen-sional) measurement system using multi-camera passive stereo vision to reconstruct 3D surfaces of free form objects. The proposed system is based on an efficient stereo correspondence technique, which consists of (i) coarse-to-fine correspondence search, and (ii) outlier detection and correction, both employing phase-based image matching. The proposed sub-pixel correspondence search technique contributes to dense reconstruction of arbitrary-shaped 3D surfaces with high accuracy. The outlier detection and correction technique contributes to high reliability of reconstructed 3D points. Through a set of experiments, we show that the proposed system measures 3D surfaces of objects with sub-mm accuracy. Also, we demonstrate high-quality dense 3D reconstruction of a human face as a typical example of free form objects. The result suggests a potential possibility of our approach to be used in many computer vision applications.

Evaluation of normal and abnormal fetal heart anatomy using 3D echocardiography

We applied 3D echocardiography to the diagnosis or exclusion of congenital heart disease (CHD) using rate gating with Doppler. Gated 3D volume data sets enabled diagnostically acceptable visualization of all cardiac structures in 16 of 29 fetuses without CHD and in 7 of 22 fetuses with CHD, and significant elements of anatomy in the remainder. In fetuses without CHD a dynamic 3D perspective of valve morphology and ventricular wall motion of the four‐ and five‐chamber view projection was available in 19/29 cases. A high quality 3D reconstruction of the site and spatial orientation of VSD could be obtained in 9/13 patients with CHD. The 2D imaging remained the principal diagnostic modality in all cases with additonal structural detail obtained by 3D imaging in only two fetuses with CHD. The 3D imaging of the fetal heart is feasible and may provide additional information of clinical value in a small number of cases with CHD when compared with 2D imaging.

Helical CT with multiplanar and three-dimensional reconstruction of nonneoplastic abnormalities of the trachea.

Helical CT is being increasingly used for the evaluation of suspected tracheal diseases. Although nonneoplastic and noninfectious diseases of the trachea are rare, their appearance on CT images may be highly suggestive of the diagnosis. High quality multiplanar and 3D reconstructions including 3D surface-shaded display and virtual bronchoscopy are helpful to characterize tracheal abnormalities and to demonstrate the location and extent of the diseases.