Patent ID: 8747419
Filing Date: 2014-06-10
Classification: A61B

Abstract:
1. A trajectory guide apparatus, comprising: a base, configured to be able to be capable of being affixed substantially in a burr hole in a skull in a human or animal subject, the base including a socket configured to be located in the burr hole when the base is affixed to the skull of the subject; a spherical or other ball, configured to be located in and pivotable with respect to the socket and to be located substantially in the burr hole when the base is affixed to the subject, such that a central pivot point of the ball is located below a surface of the skull when the base is affixed to the skull of the subject, the ball including therethrough a pivotably adjustable instrument guide ball passage providing an adjustable instrument trajectory defined longitudinally by the ball passage; an engageable ball retainer, configured to be located substantially within the burr hole when engagably coupled to the base that is located substantially within the burr hole, the retainer configured to secure the ball to inhibit pivoting of the ball to hold the instrument trajectory substantially constant; an elongate guide stem, including a proximal end and a distal end and a bore therebetween, wherein the distal end of the guide stem is configured to engageably concentrically align the bore with the ball passage, such that the guide stem extends longitudinally outward from and supported by the ball; wherein the guide stem includes sections capable of being user-separated from each other when an instrument is in the bore and the ball passage such that the instrument remains within the ball passage without being constrained by the bore after the user-separation of the guide stem sections; a first set of one or more fiducial markers, disposed in and commonly defining a unique first plane extending orthogonal to the trajectory; wherein the first set of one or more fiducial markers defines a centroid at a location in the first plane that is in a specified or determinable relationship to a location where the first plane is intersected by the trajectory; and a second set of one or more fiducial markers, disposed in and commonly defining a unique second plane extending orthogonal to the trajectory and spaced apart from the first plane; wherein the first and second sets of fiducial markers respectively include spaced-apart rings that are each concentric to the trajectory.