Abstract: A minimally invasive method of placing a delivery device substantially adjacent to vascular tissue and a device for use with such a method are disclosed. The delivery device may be a flexible biological construct with a flexible tethering means. The delivery device may be percutaneously inserted near vascular tissue such as, for example, peritoneal tissue. When the delivery device has been inserted, the tether may be used to pull the delivery device toward the vascular tissue and secure the device thereto. Contact between the front surface of the delivery device and the vascular tissue may be maintained by making and keeping the tether substantially taut. The delivery device may serve accomplish sustained delivery of active agents.

Abstract: A non-linear guidance method for radiation detection is described herein wherein a heuristic non-linear radiation detection method is utilized is for the location of sentinel nodes for staging cancer. The method of radiation detection described herein includes the steps of: Generating radiation decay rate counts wherein the counts are a sum of detected radiation decay events over a time interval; loading the counts into an array; summing selected elements of the array to generate a total count and a plurality of candidate counts; comparing the total count to one of the candidate counts to determine whether the one of the candidate counts is statistically different from the total count; using the statistically different one of the candidate counts as an output count rate; and generating an output signal using the output count rate to determine the characteristics of the output signal.