A chronic window imaging device for the investigation of in vivo peripheral nerves

Chronic imaging of the peripheral nervous system with contemporary techniques requires repetitive surgical procedures to reopen an area of interest in order to see underlying biological processes over time. The recurrence of surgical openings on an animal increases trauma, stress, and risk of infection. Such effects can greatly lessen the physiological relevance of any data recorded in this manner. In order to bypass repetitive surgery, a Peripheral Nerve Window (PNW) device has been created for chronic in vivo imaging purposes. Intravital imaging window devices have been used previously to image parts of the rodent model such as the brain, spinal cord, and mammary tissue, but currently have not been used in the peripheral nervous system because of lack of bone anchoring and access to deep nerve tissue. We demonstrate a novel surgical technique in a rat which transposes the sciatic nerve above the surrounding muscle tissue allowing the PNW access to an 8mm section of the nerve. Subsequent days of observation revealed increased vasculature development primarily around the nerve, showing that this preparation can be used to image nerve tissue and surrounding vasculature for up to one week post-implantation.