1. Free Osirix

Background: Although the utility of virtual bronchoscopy has been reported, the software for virtual bronchoscopy has not been popular because of the high cost. OsiriX is a reasonably priced software that is available to reconstruct virtual endoscopic images. Herein, we present the ability of OsiriX to enable virtual bronchoscopy.Methods: Computed tomography of the chest was performed using a 16-row multidetector.

Data in 2 mm slices from one lung were obtained from 10 patients with a lung nodule. Virtual bronchoscopic images were established by OsiriX version 5.5 (32-bit). To examine the ability to visualize small bronchi, we tried to visualize the distal bronchus if possible. We selected B 1a and B 10c for the right lung and B 1+2a and B 10c for the left lung.

In addition, to predict whether a pathologic diagnosis can successfully be made by transbronchial lung biopsy, we reconstructed virtual bronchoscopic images toward the lung nodule.Results: Bronchoscopic images were successfully reconstructed for all patients. The third to the seventh bronchi were visualized except in one patient whose right B 10 was occluded by a tumor. In all patients, the virtual bronchoscopic path reached the lung nodule, and 5 lung nodules were successfully diagnosed by transbronchial biopsy.Conclusions: OsiriX is practicable for virtual bronchoscopy at a low cost. Advances in computer technology have permitted development of virtual bronchoscopy or virtual reality images of the tracheobronchial tree using data sets derived from multidetector computed tomography (CT) of the chest. Its utility in bronchoscopic lung and lymph node biopsy has been previously reported.Software such as Bf-NAVI (Olympus, Tokyo, Japan) and LungPoint (Broncus, Mountain View, CA) are available to provide virtual bronchoscopic images.

The process of reconstructing virtual bronchoscopic images from CT data is automated; the process of finding an adequate path to a lesion is partially automated. Although these software programs are very useful, they are not widely used because of their high cost.OsiriX (OsiriX Foundation, Geneva, Switzerland) is an image-processing software dedicated to DICOM images produced by medical equipment such as CT scanners. OsiriX has been specifically designed for navigation and visualization of multimodality and multidimensional images, including virtual endoscopy. OsiriX is an open source software and only works on Mac OS (Apple, Cupertino, CA). A notable advantage of OsiriX is that the 32-bit version is free; OsiriX MD, the 64-bit version cleared by the Food and Drug Administration for primary diagnosis, costs only 599 US dollars. OsiriX has made virtual bronchoscopic images available at a low cost, which can help virtual bronchoscopy gain popularity.In this paper, we present the ability of OsiriX to reconstruct virtual bronchoscopic images.

PATIENTS AND METHODS SubjectsThe institutional review board approved the protocol, and written informed consent was obtained from all patients. We obtained approval from our institution to use patient medical records for our study and patient confidentiality was maintained.Subjects consisted of 10 patients with lung nodules, evenly split between the right and left lungs. Chest CT without contrast was performed using a 16-row multidetector scanner with 2 mm slices pitch without overlap from one lung. Virtual Bronchoscopic Lung Biopsy (VBLB)Bronchoscopy was not performed in 2 of 10 patients because the lesion was not bronchoscopically accessible. Three patients who underwent bronchoscopy did not undergo surgery because 2 patients were diagnosed with lung infection and the other patient was diagnosed with metastatic lung cancer.

In 5 of 10 patients, transbronchial lung biopsy followed by lung resection was performed.To predict whether the transbronchial lung biopsy resulted in the correct pathologic diagnosis, we reconstructed virtual bronchoscopic images toward the lung nodule. If the virtual bronchoscopic pathway reaches the lung nodule, we expect that transbronchial lung biopsy would result in an accurate diagnosis. DISCUSSIONIn previous reports, the usefulness of virtual bronchoscopic navigation has been described.

It can shorten the duration of bronchoscopic examination and improve the rate of accurate diagnosis.Software programs such as Bf-NAVI and LungPoint have been developed to easily reconstruct virtual bronchoscopic images; these programs can automatically extract the trachea and bronchi from CT images and reconstruct virtual bronchoscopic images. However, one limitation of the software is the prohibitive cost, which has limited its use. These programs cost at least 30,000 US dollars.

Free Osirix

In contrast, OsiriX 32-bit is a free software for Mac. Even the 64-bit version cleared by the Food and Drug Administration costs only 599 US dollars. Virtual bronchoscopic images can be reconstructed on a Mac platform at a low cost.We demonstrated that OsiriX has enough functionality to reconstruct virtual bronchoscopic images. Everhardt et al reported that LungPoint detects and visualizes 3 mm or larger airways. As shown in, we were able to visualize airways smaller than 2 mm. OsiriX has an additional advantage over Bf-NAVI and LungPoint.

Sometimes Bf-NAVI and LungPoint fail to detect and extract the trachea and bronchi from the CT data because of anatomic anomalies. As OsiriX does not use an extraction process, virtual bronchoscopic images can be obtained in all cases using OsiriX.In addition, OsiriX is not only useful for reconstructing virtual bronchoscopic images but it may also be useful for predicting whether transbronchial biopsy can be successful. If the path reaches the lung nodule, there is a high probability that transbronchial biopsy will be successful. We named this prediction process “virtual bronchoscopic lung biopsy.” Using VBLB, we can select patients for whom bronchoscopic biopsy can yield a diagnosis.

By identifying patients for whom bronchoscopic biopsy would have a low yield, other appropriate modalities such as CT-guided percutaneous biopsy and thoracoscopic biopsy can be selected.With OsiriX virtual bronchoscopy, although virtual bronchoscopic image reconstruction is automated, we have to manually reconstruct the VBLB pathway. However, the process is so easy that a VBLB pathway can be reconstructed in only 5 to 10 minutes. Most bronchoscopists can reconstruct virtual bronchoscopic images using OsiriX in a short period of time at a low cost.Recently, increasing medical costs pose an important problem in many countries.

Nevertheless, many new technologies have been developed and applied. Virtual bronchoscopy is a popular example in the field of respiratory medicine. Although virtual bronchoscopy has great potential for meaningful clinical application, it is difficult to implement because of the high price of commercial software.

However, OsiriX can efficiently reconstruct virtual bronchoscopic images at a low cost. With OsiriX, virtual bronchoscopy can become popular at a relatively low cost. OsiriX can contribute to the widespread adaptation of virtual bronchoscopy.

A multidimensional image navigation and display software was designed for display and interpretation of large sets of multidimensional and multimodality images such as combined PET-CT studies. The software is developed in Objective-C on a Macintosh platform under the MacOS X operating system using the GNUstep development environment. It also benefits from the extremely fast and optimized 3D graphic capabilities of the OpenGL graphic standard widely used for computer games optimized for taking advantage of any hardware graphic accelerator boards available. In the design of the software special attention was given to adapt the user interface to the specific and complex tasks of navigating through large sets of image data. An interactive jog-wheel device widely used in the video and movie industry was implemented to allow users to navigate in the different dimensions of an image set much faster than with a traditional mouse or on-screen cursors and sliders.

The program can easily be adapted for very specific tasks that require a limited number of functions, by adding and removing tools from the program’s toolbar and avoiding an overwhelming number of unnecessary tools and functions. The processing and image rendering tools of the software are based on the open-source libraries ITK and VTK. This ensures that all new developments in image processing that could emerge from other academic institutions using these libraries can be directly ported to the OsiriX program. OsiriX is provided free of charge under the GNU open-source licensing agreement at. THE RAPID EVOLUTION of digital imaging techniques and the increasing number of multidimensional and multimodality studies constitute a challenge for PACS workstations and image display programs.

With the improvement of spatial resolution of multi-detectors CT scanners and the emergence of multimodality exams like PET-CT or Cardiac-CT, traditional two-dimensional image viewers and image display programs are becoming unsuitable for interpretation of these large sets of images. For most tomographic imaging techniques such as magnetic resonance imaging (MRI) and CT, the traditional 2D acquisition technique of cross-sectional slices is evolving into 3D volume acquisitions with isotropic voxel sizes resulting in very large data sets. The conventional way of reviewing these images slice-by-slice is too cumbersome for interpreting the 800 to 1,000 slices that can be acquired with multi-detector CT scanners. These large sets of images require additional image processing and reformatting to make them suitable for efficient and rapid image navigation and image interpretation. In most cases this can only be achieved on high-end dedicated 3D workstations that can provide thick-slab maximum intensity projections (MIP), orthogonal and oblique multiplanar reformatting (MPR), and 3D volume and surface rendering. These recent changes in the acquisition modalities require radiologists to use expensive dedicated 3D processing workstations to properly interpret these exams.

Diagram showing the simple process used for image fusion. (1) The overlay image (PET image) is selected and (2) a color scale is applied.

(3) The image fusion is initiated by drag-and-drop of the PET window title bar over the CT window resulting in (4) a fused image set obtained by color blending of the two original sets. The image fusion is instantaneous and the user can continue to navigate through the whole set of fused images and apply any of the processing tools such as intensity and contrast adjustment, slice thickness adjustment, MIP and MPR. DISCUSSION AND CONCLUSIONSRadiology imaging modalities are evolving from conventional sets of 2D tomographic slices to 3D volumetric acquisition extending to a fourth or fifth dimension with temporal and functional data that can be acquired with ultrafast CT and MR scanners with combined PET/CT scanners. To allow radiologists and clinicians to conveniently and efficiently interpret these large exam sets, traditional image viewers have to be re-designed and tailored to a new paradigm of multidimensional image navigation visualization, and manipulation. By combining the performance of new hardware components and the wealth of existing open-source image processing and manipulation tools, it is now possible to develop a new generation of high-performance multidimensional image viewers for off-the-shelf personal computers. These advanced navigation and visualization tools were traditionally only accessible on expensive dedicated 3D workstations, thereby restricting their use to specialist radiologists.

With easier access to these multidimensional navigation and visualization tools in standard personal computers, they should soon become complementary tools for routine interpretation of complex diagnostic studies.One of the key features of the OsiriX software is its flexible user interface allowing users to customize the program by adding and removing tools and functions from the tool bar and menus of the program. This also allows the creation of “customized” versions of the program for specific groups of users. Users who are not computer experts can adopt simpler versions of the software containing only a limited number of essential tools.

Specialized versions of the program could be easily customized for specific medical specialties or for specific clinical applications without the need for any additional programming or software development.The multithreading ability of the software that allows OsiriX to take full advantage of multiprocessor computers ensures a scalability of performance that can be expected from future generation computers. The same software architecture will also allow a migration toward the emerging technology of Grid Computing. With Grid Computing technology, it is possible to significantly enhance image processing performance by using clusters of computers.

The grid technology is already used for large 3D virtual reality software applications to greatly accelerate the rendering time. In the computer animation movie industry, including PIXAR and other industry leaders, Grid Computing technology has taken a prominent role. Most of the rendering is performed based on clusters of computers.

Grid Computing is also used extensively in large multicentric bioinformatic projects for genome analysis., We anticipate that Grid Computing technology could significantly improve the performance of 3D medical imaging rendering techniques. The VTK library already supports Grid Computing rendering through the open-source and cross-platform standard Message Passing Interface (MPI).

Apple Computer recently announced a new technology, X-Grid, that will facilitate the management and configuration of large clusters of computers. With the X-Grid technology it will be easy to connect all computers of a radiology department to share complex processing and rendering tasks during processor idle time.

In large academic radiology departments it is common to have a relatively large number of computers that are only partially used and remain idle for significant amounts of time. The Grid Computing technology makes it possible to take advantage of idle computer time for performing computational intensive tasks needed for 3D rendering applications across the network. By adopting the X-Grid technology, OsiriX, which is already multithread compliant, could benefit from a significant improvement in performance if used in a network of multiple computers.OsiriX is distributed freely as open-source software under the GNU licensing scheme at the following Web site:.