Microendoscopes for imaging of the pancreas

Patients diagnosed with pancreatic cancer have a 5-year survival rate of only 3%. Endoscopic imaging of the pancreas is limited by the small size of the pancreatic duct, which has an average size of 3 mm. To improve imaging capabilities for the pancreatic duct, two small catheter-based imaging systems have been developed that will fit through the therapeutic channel of a clinical endoscope and into the pancreatic duct. One is a miniature endoscope designed to provide macro-imaging of tissue with both white light reflectance and fluorescence imaging modes. The 1.75 mm diameter catheter consists of separate illumination and imaging channels. At a nominal focal distance of 10 mm, the field of view of the system is ∼ 10 mm, and the corresponding in-plane resolution is 60 μm. To complement the broadfield view of the tissue, a confocal microendoscope with 2 μm lateral resolution over a field of view of 450 μm and 25 μm axial resolution has been developed. With an outer diameter of 3 mm, the catheter in this system will also fit through the therapeutic channel and into the pancreatic duct. Images of tissue with both the miniature endoscope and confocal microendoscope are presented.