A vaso-occlusive implant has a primary helical-coil shape that defines a
primary axis and a three-dimensional secondary shape. The secondary shape
includes a substantially helical section and a second section having a
plurality of non-overlapping loops or loop sections. Each loop defines a
plane that is oriented at an angle from about 30-150 degrees relative to
a plane defined by an immediately preceding or immediately succeeding
loop along the primary axis. The coil sections or loops can be generally
circular loops or other smooth shapes.