Noncontact remote dimensional measurements in difficult to access areas are an important part of nondestructive remote visual evaluation in many industrial fields. Endoscopes are the major devices that are used for this purpose. It is impossible, however, to measure the actual size of the imaged objects using an endoscope that is not equipped with additional features, as the instrument magnifies object details depending on its distance from the endoscope tip, and this distance is unknown, and is constantly changing during the examination. This measurement situation changed, in 1996, when Olympus Industrial introduced a two objective measuring endoscope that produced an optical stereopair that could be used to determine distance via the triangulation method used in classical two-camera photogrammetry. The diameter of the outer shaft of this endoscope is 4.4mm, and the device is widely used in the industrial field. The medical community, however, has not embraced this device, most likely for two reasons: (i) a reduced angle of view (700) compared to the larger angle of view (more than1100) used in endoscopic visual examination;and (ii) the high cost involved in the measurement process. Diagnostic endoscopy is typically qualitative. The physicians make conclusions from observation of the tissue colors and abnormalities. High quality color reproduction devices with a wide field of view are in use. As medical diagnostics progresses, however, there are more requests for quantative measurements during endoscopy. The development of an endoscopic supportive tool with measurement capabilities, that will not interrupt the endoscopic procedure, but can rapidly provide quantative support to the diagnosis, would be valuable to medical practitioners. This tool would best be delivered through the instrumental channel of the endoscope, as are other supportive tools. The diameter of the instrumental channel is restricted, however, and a two lens probe, such as the Olympus probe, will not fit in the channel. Intelligent Optical Systems (IOS) is collaborating with the UCLA Medical Center and School of Engineering to develop technologies specifically focused on the fabrication of novel unique surgical tools and MEMS devices to enhance endoscope measurement capabilities. IOS has developed and proven a method of producing a stereopair using a single lens with an optically transparent tilting plate in front of the lens. UCLA researchers have fabricated and demonstrated the operability of a MEMS device incorporating an optically transparent plate. In this project, the IOS-UCLA team proposes to develop a single lens endoscopic measuring probe no more than 2.5mm in diameter. In Phase I, the team will fabricate and demonstrate a measuring endoscope probe prototype 5.5mm in diameter, based on an already fabricated tilting plate;develop measurement algorithms and software, and modify the MEMS fabrication flow process to downsize the device to the 2.5mm dimension. A precommercial prototype of the measuring endoscopic probe, ready for FDA approval, will be presented at the end of Phase II.
Requirements for quantifying the size of lesions, polyps, and other pathological parts of tissue during endoscopy diagnostics, are growing. Reliable, low cost, high accuracy tools to support endoscopy procedures with quantative data, however, do not exist. IOS, in collaboration with UCLA researchers, proposes to develop a measuring endoscopic probe, a tool that can be inserted into the instrumental channel of the endoscope, and will provide dimensional measurements of biological objects during endoscopic procedures. This novel tool will help to reduce the number of uncertainties that still exist in endoscopy diagnosis.
