Virtual Scopy with Multidetector CT

Abstract

Virtual scopy is a computerized, non-invasive technique used in simulating views provided by a fiber optic endoscope. Multidetector CT (MDCT) enhances the technique of Virtual scopy, by its z-axis resolution, faster data acquisition and improved 3D-image quality. The common application included Virtual Colonoscopy, Bronchoscopy, Gastroscopy, Angioscopy, Labyrinthoscopy, Thoracoscopy and Stentoscopy. Of the 45 Virtual scopies referred to Radiology Department at INHS Asvini, the single largest application was Virtual Angioscopy followed by Stentoscopy and the smallest was evaluation of larynx, labyrinth, colon and mediastinum accounting for 3 each. Endoscopy data and histopathological diagnosis was available in 17 patients, who underwent Virtual studies of larynx, airway, stomach, mediastinum and colon. MJAFI 2006; 62 : 60-63Key Word : Virtual Endoscopy, Virtual scopy, Internal Volume Rendering injector and CARE Bolus software. In most cases, a detector configuration of 4 x 1 mm, a table feed of 5 mm/rotation at 140 mAs, 120 kV and a gantry rotation time of 500 msec was used, resulting in a slice thickness of 0.5 mm. Processing of Image DataImages from all 45 cases were first interpreted using cine viewing of axial images and secondary MPRs on the main console. Subsequently, volume rendering, 3D scopic views and fly-throughs were generated on a dedicated Leonardo workstation. Virtual scopy images were generated using volume and surface rendering. Four distinct data parameters, i.e. window width, level, opacity and brightness were interactively adjusted, influencing the images generated.For Virtual Colonoscopy, a colon model was created with segmentation of the colon. Guided navigation using a centerline simulated a flight path of the entire colon. With real-time volume rendering at more than 10 frames/sec, interactive navigation of the endoscopic views analysed the colonic lumen. 2-D views corresponding to the navigation viewpoint were available for verification purposes. By turning, zooming, and rotating during the "fly-through" examination of the endoscopic views, the structures were more closely examined. ResultsOf the 45 Virtual scopies performed, the single largest application was Virtual Angioscopy followed by Stentoscopy. The smallest sub-groups were evaluation of larynx, labyrinth, colon and mediastinum accounting for 3 patients each. Endoscopy data and histopathological diagnosis was available in 17 patients, who underwent virtual studies of larynx, airway, stomach, mediastinum and colon. Of the 17 cases, the CT scopy diagnosis matched with Endoscopic/

Contribution of Virtual Anatomic Models to Medical Education

“…Virtual colonoscopy, bronchoscopy, gastroscopy, angioscopy, laparoscopy, thoratoscopy and stethoscopy applications can be carried out in this way (Indrajit et al, 2006 In ultrasound--controlled biopsy for liver, simulator based on virtual reality provides a feedback related with a realistic vision and contact (Ni et al, 2011;Villard et al, 2011). These simulations plays an important role in obtaining 3D images necessary in making practice in the order that should also be followed in biopsy of prostate (Deguchi et al, 2006).…”

“…By means of virtual observation, the anatomic structures of internal organs in body cavity can be evaluated non--invasively via computer and simulation of a fiber optic endoscopy can be performed. Virtual colonoscopy, bronchoscopy, gastroscopy, angioscopy, laparoscopy, thoratoscopy and stethoscopy applications can be carried out in this way (Indrajit et al, 2006). Computer--aided design methods for pediatric surgery and retractable coronoid surgery instruments, named as pylorohooks and evaluated as virtual reality model for laparoscopic pyloromyotomy, were developed as modern bioengineering instruments (Decou et al, 2002).…”