Endoscopic imaging

Theory and Equipment. Many diseases of the human body can be identified by visual appearance. Tumors in the upper gastrointestinal (GI) tract, for example, possess a characteristic salmon pink color (3). The presence of such a color can be an indication of disease. Endoscopy is the medical imaging tool used to detect such colors in the inside of hoUow internal organs such as the rectum, urethra, urinary bladder, stomach, colon, etc. An endoscope is the instmment used to perform endoscopy. Endoscopic imaging involves the production of a tme color picture of the inside of the human body using lenses and either hoUow pipes, a fiber optic bundle, or a smaU CCD camera. AU three use a large field-of-view, sometimes referred to as a fish eye, lens to aUow a 180° field of view. 

Each of the endoscopic imaging procedures is relatively risk free and painless when performed by competent and weU-trained individuals using a local anesthetic. Eetoscopy has the highest risk. There is a 10% increased probabiUty of premature deUvery and 10% higher fetal loss rate. 

FIGURE 5.10 (a) Prototype CARS endoscope image of 0.75-(xmpolystyrene beads embedded in agarose gel spin-coated on a coverslip (Ar = 2845 cm ). The image dimension is 29 (xm x 29 Xm (128 x 128 pixels). The pump and Stokes powers at the sample were 80 mW each, with a pixel dwell time of 1 ms. (b) CARS intensity profile along the white line in (a). The CARS contrast decreased when the system was tuned off the resonance maximum. 

Fig. 16.5. a Advanced gastric cancer. Wall stratification has been totally destroyed and the extramural margin is irregular, b Endoscopic image of the same case as shown in Fig. 16.5a. c Endoscopic ultrasound image of an advanced gastric cancer. Focal wall thickening without wall stratification is observed... 

KothapaUi, S.-R., et al. Endoscopic imaging of Cerenkov luminescence. Biomedical Optics Express 3(6), 1215-1225 (2012)... 

The current opinion is that the technology available is able to produce high quality virtual endoscopic images. Although axial and multiplanar (MPR) views are usually adequate for detecting a vascular disorder, virtual angioscopic views better define anatomic details, or this technique could be simply an alternative method for data presentation as 3D volumetric data sets continue to increase in size (Carrascosa et al. 2005 Glockner 2003). 

Pozzi Mucelli et al. (1997), who first tried to generate virtual endoscopic images of the tympanic... 

Rubin GD, Beaulieu CF, Argiro V, Ringl H, Norbash AM, Feller JF, Dake MD, Jeffrey RB, Napel S (1996) Perspective volume rendering of CT and MR images applications for endoscopic imaging. Radiology 199 321-330... 

Using both surface and volume rendering algorithms, virtual endoscopic images resembling con-... 

Most esophageal tumors are diagnosed by endoscopy, with thoraco-abdominal axial CT used to stage tumor spread acquisition of 3D data set permits acquisition of three-dimensional modeling, virtual endoscopic images, and conventional axial CT information within a single examination. 

The simulation of a fiber optic perspective can be obtained trough dedicated software that reconstructs CT and MR images in three dimensions by creating surface or volume-rendered endoscopic images (Rubin et al. 1996). 

Fig. 13.3a,b. Inverted diverticulum pseudopolypoid shape on virtual endoscopic images. On 2D images, these lesions contain some air, residual stool, or fat attenuation because of a central umbilication in the inverted part of the diverticulum or due to an inclusion of perisigmoidal fat. (Used with permission of Lefere et al. 2003)... 

Fig. 31.1a-f. (continued) CTC showing pedunculated adenomatous polypoid lesion. c,d Three-dimensional threshold-rendered endoluminal CT colonograph and corresponding conventional endoscopic image showing the precise correlation between radiological and endoscopical aspect of the lesion... 

Detection of Gastrointestinal Disease in Endoscope Imaging System... 

Nishioka N S (1998) Experience with a real-time video processor for enhancing endoscopic image contrast. Gastrointestinal Endoscopy 148(1)... 

Endoscopic imaging is an invaluable diagnostic tool allowing minimally invasive access to tissues deep within the body. It has played a key role in screening colon cancer and is credited with preventing deaths through the detection and removal of precancerous polyps. Because of limited depth of penetration associated with most... 

---