Abstract: Methods for prenatal screening for trisomy 21 employ examination of the fronto-maxillary facial (FMF) angle of a fetus. The methods may comprise obtaining a two or three dimensional image of a fetal face, measuring the FMFbone angle and/or FMFskin angle on the image, and comparing the measured FMFbone angle and/or FMFskin angle with an FMFbone angle and/or FMFskin angle characteristic of chromosomally normal fetuses. A measured FMFbone angle and/or FMFskin angle greater than the FMFbone angle and/or FMFskin angle characteristic of chromosomally normal fetuses provides an indication of an increased likelihood of the occurrence of trisomy 21 in the fetus.

Abstract: Methods for prenatal screening for trisomy 21 employ examination of the fronto-maxillary facial (FMF) angle of a fetus. In one embodiment, the methods comprise obtaining a two or three dimensional image of a fetal face, measuring the FMFbone angle on the image, and comparing the measured FMFbone angle with an FMFbone angle characteristic of chromosomally normal fetuses, wherein a measured FMFbone angle greater than the FMFbone angle characteristic of chromosomally normal fetuses provides an indication of an increased likelihood of the occurrence of trisomy 21 in the fetus.

Abstract: A needle guide system comprises a base adapted for non-pivotal connection to an imaging device, an arm pivotally connected to the base, and a needle guide pivotally connected to the arm at a point distal from the arm-base connection. The needle guide is adapted to receive at least one needle. The length of the arm extending between the base and the needle guide is adjustable. Methods for positioning a needle relative to an imaging device employ the needle guide system.

Abstract: A needle guide system comprises a base adapted for non-pivotal connection to an imaging device, an arm pivotally connected to the base, and a needle guide pivotally connected to the arm at a point distal from the arm-base connection. The needle guide is adapted to receive at least one needle. The length of the arm extending between the base and the needle guide is adjustable. Methods for positioning a needle relative to an imaging device employ the needle guide system.

Abstract: A shoulder is connected to a transducer housing in substantial alignment with the plane of an ultrasound beam provided at one end of the housing. An ascending link is pivotally connected to the shoulder, a descending link is pivotally connected to the ascending link and a needle mount is pivotally connected to the descending link. The ascending link, descending link and needle mount are movable in substantial alignment with the plane of the ultrasound beam. The needle guide may be generally cylindrical and a disposable needle-receiving sleeve may be inserted into a guideway formed in the needle mount. Alternatively, the needle mount may be a disposable cube-like structure readily attachable to and detachable from the descending link. In the latter form, the needle mount is provided with a guideway slot defined by relatively spaced apart end walls of the mount which are generally equal in height to the width of the guideway defined by the space therebetween.