Sinus track

Other important components of the initial evaluation include a medical evaluation including both a medical history and physical examination. This can identify medical consequences of substance abuse, such as liver impairment from chronic alcohol abuse or sinus complications from cocaine use, as well as reveal needle tracks from a variety of self-injection sites that might not be readily apparent to casual observation. 

To confirm the stereotaxic orientation of sections in the brain used for this atlas, reference needle tracks were made perpendicular to the horizontal and coronal planes. For brains sectioned in the coronal plane, vertical needle insertions were made at 2.0 mm intervals through the brain, except for the penetrations at 0.7 mm anterior to the interaural line, which was chosen to avoid rupture of a venous sinus. Ten such needle tracks appear on coronal plates of this atlas. Three horizontal needle insertions perpendicular to the coronal plane were made from the posterior of the brain at 1.0, 3.0, and 5.0 mm above the interaural line and approximately 1.0 mm lateral to the midline. The reference tracks from the horizontal needles appear as small holes in coronal sections. 

Image-Guided Sinus Surgery Using a Navigational System 163 Comparison of Tracking Systems 166... 

Fig. 3.4 VDD mode. Sensing occurs in both the atrium and the ventricle but pacing only occurs in the ventricle. Atrial events may be tracked and followed by ventricular-paced events (PV). When there is a sinus pause or a PVC not followed by a P wave, the next event will be a ventricular-paced event rather than an atrial-paced event in DDD mode. The AV and PV intervals can be programmed separately in some pulse generators.

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