The invention relates in general to joining of electrical conductors and more specifically to devices and methods for connecting medical wires.
Medical wires, also sometimes referred to as biomedical wires and leads, provide electrical paths between different locations within a host. Medical wires are typically very thin, insulated wires formed of materials that are compatible with biological substances and which can be implanted into a host to provide electrical connections between medical devices, connectors, electrodes and other wires. Techniques include implanting medical devices such as, for example, sensors and stimulators into living tissue. These medical devices are often connected to an electrode through a medical wire that allows electrical energy to travel between the implanted medical device and the electrode. Such an arrangement is useful in situations where the medical device can not be implanted at the sensing or stimulation target area of the tissue due to size or other limitations. Other medical techniques also require the use of insulated electrical conductors such as medical wires and surgical wires to mechanically and electrically connect devices, connectors and other wires.
Conventional techniques for connecting medical wires are significantly limited. For example, wire connection techniques that include welding are less than optimum due to the limited types of materials that can be welded and convenience issues. All implanted materials must provide long-term compatibility with the host such that tissue inflammation, cellular alteration, and other adverse reactions are avoided or minimized. In addition, the materials should not be susceptible to damage or deterioration due to chemicals, electrolytes and other substances present in the host. Many biologically compatible materials can not be welded to other biologically compatible materials. For example, titanium and titanium alloys can not be welded to platinum, iridium or alloys of platinum and iridium. In addition, the use of welding equipment is often inconvenient and impractical. Welding at a surgery location, for example, can not be easily facilitated.
Other techniques for connecting medical wires include crimping connectors to the medical wire or device. Such connectors may include metal sleeves or tubes that are crimped around the conductor of a medical wire. Many conventional crimping techniques, however, are limited in that the insulation on the medical wire must be stripped before crimping. The insulation is difficult to remove. Further, insulation particles may irritate healing tissue and cause other adverse effects if the wire is stripped at the surgical site. Most methods of removing insulation cause changes in the chemical composition of the insulation resulting in the creation of pyrogens or toxic byproducts. Other crimping techniques are further limited by the awkward crimping tools that are difficult to use with the small and delicate medical wires, connectors and devices that require precision assembly to form a reliable and sturdy connection.
Accordingly, there is need for device and a method for easily, efficiently, and conveniently connecting medical wires that result in reliable electrical connections.