Feasibility of Air Transport Simulation Training: A Case Series.

Limited clinical site availability and an increased need for clinical training experiences often make it difficult for prehospital health care providers to complete new and annual training requirements. Medical simulation provides an alternative learning environment that provides trainees the opportunity to acquire and perfect new clinical skills without compromising patient care. The following is a detailed description of an air medical transport simulation of a neonate with hypoxic ischemic encephalopathy requiring transport to a higher level of care. Patient parameters were altered during flight to simulate potential complications unique to air medical transport. Use of this training strategy is particularly beneficial for low-volume, high-risk patients, and these lessons can be applied across all age patient groups, making the experience broadly applicable.

Enhanced visibility of colonic neoplasms using formulaic ratio imaging of native fluorescence.

BACKGROUND AND OBJECTIVES: Colonoscopy is the preferred method for colon cancer screening, but can miss polyps and flat neoplasms with low color contrast. The objective was to develop a new autofluorescence method that improves image contrast of colonic neoplasms. STUDY DESIGN/MATERIALS AND METHODS: We selected the three strongest native fluorescence signals and developed a novel method where fluorescence images are processed in a ratiometric formula to represent the likely cellular and structural changes associated with neoplasia. Native fluorescence images of fresh surgical specimens of the colon containing normal mucosa, polypoid and flat adenomas as well as adenocarcinoma were recorded using a prototype multi-spectral imager. Sixteen patients, with a mean age of 62 years (range 28-81) undergoing elective resection for colonic neoplasms were enrolled. High contrast images were seen with fluorescence from tryptophan (Tryp), flavin adenine dinucleotide (FAD) and collagen. RESULTS: When the image intensity of Tryp was divided pixel by pixel, by the intensities of FAD and collagen, the resulting formulaic ratio (FR) images were of exceptionally high contrast. The FR images of adenomas and adenocarcinomas had increased Weber contrast. CONCLUSIONS: FR imaging is a novel imaging process that represents the likely metabolic and structural changes in colonic neoplasia that produces images with remarkably high contrast.

Ratio images and ultraviolet C excitation in autofluorescence imaging of neoplasms of the human colon.

The accepted screening technique for colon cancer is white light endoscopy. While most abnormal growths (lesions) are detected by this method, a significant number are missed during colonoscopy, potentially resulting in advanced disease. Missed lesions are often flat and inconspicuous in color. A prototype ultraviolet spectral imager measuring autofluorescence (AF) and reflectance has been developed and applied in a study of 21 fresh human colon surgical specimens. Six excitation wavelengths from 280 to 440 nm and formulaic ratio imaging were utilized to increase lesion contrast and cause neoplasms to appear bright compared to normal tissue. It was found that in the subset of lesions which were most difficult to visualize in standard color photographs [low contrast lesions, (LCLs)] a ratio image (F340/F440) of AF images excited at 340 and 440 nm produced extraordinary images and was effective in about 70% of these difficult cases. Contrast may be due to increased levels of reduced nicotinamide adenine dinucleotide, increased hemoglobin absorption, and reduced signal from submucosal collagen. A second successful ratio image (R480/R555) combined two reflectance images to produce exceptional images especially in particular LCLs where F340/F440 was ineffective. The newly discovered ratio images can potentially improve detection rate in screening with a novel AF colonoscope.