Single wavelength micro-endoscopy in non-surgical vascular lesion diagnosis & characterization.

Malignant and dysplastic epithelial lesions have often been reported to excite vascular responses by histopathological characterization. Little is reported concerning in vivo real-time imaging of vascular patterns and flow in health or disease but the development of miniature imaging instrumentation has now allowed such developments. We describe the application of a selective wavelength (540 nm) epi-illumination Hopkins pattern endoscopic imaging system to image vascular tissues and capillary blood flow in vivo. The contrast mechanism in such imaging was characterized, haemoglobin acting as a chromatic transmission filter despite endoscopy being a non-invasive and therefore principally reflection mode imaging system. In vivo adrenergic vascular responses, capillary flow rate variations over time and variations in normal capillary architecture around the oral cavity were recorded; demonstrating that simple imaging systems can be used for non-surgical diagnosis and characterization of vascular lesions, tumours and treatment responses.