Novel Cmos Image Sensor Technology Improves Diagnostic Accuracy and Enables Economic Viability of Disposable Medical Imaging Devices

Objective/Background
Image senor technologies such as charge-coupled devices (CCDs) image sensors have played a major role in digital medical imaging during past twenty years. With technological advancements such as backside illumination (BSI), CMOS image sensors began to take off in medical imaging applications. Novel CMOS-based image sensors offer enhanced image quality, low power consumption, improved system integration capability, and a small size.

Because CMOS sensor devices are built using traditional CMOS semiconductor manufacturing processes, they have significantly reduced the cost of camera modules for medical imaging devices, which are the key component of endoscopes. Further advancement of the complementary system that supports the CMOS sensors, such as lens, image-signal processing, and display, enhanced camera performance, resulting in broader adoption of CMOS image sensors in a wide range of medical endoscopy applications. The purpose of this study is to evaluate novel CMOS image sensor technologies that enable disposable medical endoscopic devices.

Description
OmniVision’s OV6930 is an ultra-compact CMOS image sensor designed specifically for use in medical devices. With a packaged footprint of only 1.8 x 1.8 mm, the OV6930 is an ideal solution for endoscopic applications that require a small profile, including bronchoscopy, colonoscopy, gastroscopy, OB-GYN and urology.

The OV6930 combines ultra-low power consumption with OmniVision’s best-in-class OmniPixel3-HS™ technology, enabling low-light performance of 3300 mV/lux-sec. It supports cabling up to 14 feet, allowing the camera head on the endoscope tip to be separated from handles and display panel.

Preliminary results
While colonoscopy is widely regarded in the medical community as the “gold standard” for the detection of abnormalities in the colon, which are precursors to almost all cases of colon cancer, previous research has revealed that 12-24 percent of polyps and a significant number of cancers can be missed during colonoscopy. This is especially so if polyps lie hidden behind folds in the colon wall.

Based on Omnivision’s novel CMOS image sensor technology, an FDA-cleared, disposable, catheter-based retroscope (providing a continuous backward-looking view) for use with a standard colonoscope (providing the usual forward view) was developed. Review of preliminary results in clinical studies using this Third Eye Retroscope™, demonstrate an extraordinary increase in accuracy of diagnosing adenomas, or pre-cancerous polyps, of 23.2 percent when used in conjunction with a traditional colonoscope.

Conclusions / future directions.
By providing excellent low-light sensitivity, superior image quality and performance in a very small form factor, the OV6930 allows for ultra-compact camera designs, making medical procedures, such as colonoscopies, minimally invasive for the patient. As a result, this technology could replace other image-capture systems, leading to the emergence of new disposable endoscope tips (camera modules), culminating in a new generation of disposable instruments.

Benefits of this new CMOS image sensor technology, especially BSI technology, includes improved image qualities and reduced manufacturing costs, making disposable endoscopes not only a trend, but a viable alternative compared to standard endoscopes. Clinical studies are warranted in order to further validate these results.