High Resolution Light Imaging System for Teeth and Tissues

Abstract

Small lesions in tissues are difficult to detect by X-ray techniques. Several other techniques such as ultrasound, thermography, and light imaging systems have been investigated in attempts to increase the detection of these small lesions. It is difficult to detect whether lesions are benign or cancerous using thermography, ultrasound cannot detect small lesions, but is the best available method to distinguish between cysts and cancerous lesions. Previously described light imaging systems can detect cancerous lesions, but only if they are large and near the surface. To increase the capability of light imaging systems to detect small lesions deep inside in a medium, we have developed a new laser-based imaging system. We have found that with this system lesions as small as 1 mm2 could be detected even in thick media such as excised breast tissue, anesthetized mice, and extracted whole teeth. We have observed cysts and cancerous lesions in breast tissues ¾ of an inch thick, and small anatomical details such as sections of the spine in mice. One of the main advantages of this technique is that it is totally harmless to tissues and teeth because of its low laser power (8 mWt), allowing it to be used as often as necessary during any clinical procedure. Investigations also show that the resolution of our present system could be further improved to about 0.1 mm2 by incorporating new semiconductor detector devices, which could also be used to adapt this technique for full clinical operation.