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Robert H. Pudenz and C. Hunter Shelden

support to the theory of transmission of lines and waves of force through the brain. According to this observer the head in motion resembles a bullet in flight since both have a line of force in their trajectory. When the forward motion of the head is suddenly arrested the line of force is immediately reversed and extends backward through the nervous tissue to a point opposite the site of impact. Presumably, waves of force spread outward from the main line of force. The lines and waves of force are modified by the angle of impact and by the deflection and diffusion

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Joseph C. Barnett and Arnold M. Meirowsky

, feeling that the important factor, as Schorstein stated, was the intracranial confinement of the hematoma; this being in contradistinction to the avulsive type of wound in which cerebral and meningeal bleeding readily escapes from the wound. Matson and Wolkin 3 observed that in instances in which the missile was found located near a cortical surface opposite or within the line of trajectory of the missile, there was likelihood of hematoma formation in the region of the missile. There were 15 instances of this particular situation encountered in the series. In 6 of

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William A. Stewart, William L. Stoops, Peter R. Pillone and Robert B. King

, 32, 33 indicate that the pattern of axonal trajectories emanating from nucleus caudalis differs from that of the more rostral components of the spinal trigeminal nuclear complex (nucleus interpolaris and nucleus oralis) and the main sensory nucleus. Furthermore, the soma of trigeminal fibers which project directly to the midbrain and thalamic centers associated with nociperception are contained only within nucleus caudalis. This report presents the findings of an electrophysiologic study devised to identify midbrain and thalamic loci activated by a trigeminal

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E. S. Flamm and J. M. Van Buren

after the lumbar subarachnoid injection of air with the head flexed to show the posterior commissure; 2. an erect antero-posterior view immediately after a second injection of air to show the midline of the 3rd ventricle; 3. a lateral hanging head film with the patient supine to show the anterior commissure (occasionally the posterior commissure is demonstrated on the same view). A centimeter rule on a plane at right angles to the x-ray trajectory at the mid-point of the skull allows correction of magnification. 10 Transfer of commissural landmarks on the lateral

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L. W. Organ, R. R. Tasker and N. F. Moody

about the thalamus 11.0 mm lateral to the midline (see ref. 7). The radiologically calculated probe trajectory is shown, with probe depth along the trajectory marked in centimeters. There is a good correspondance between structure and impedance within the region illustrated. The profile is flattened in the 1st cm because other penetrations passed through the same area of brain. A second oscilloscope, a Tektronix RM 561A, is used for a time-base display of V BC taken from the vertical signal output of the 564. This allows the operator to see the variation in

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Hazards of Stereotaxic Thalamectomy

Added Safety Factor in Corroborating X-Ray Target Localization with Neurophysiological Methods

J. Taren, G. Guiot, P. Derome and J. C. Trigo

results in paresthesias; inferiorly by the corpus Luysi, the destruction of which results in ballismus; and anteriorly by the anterior one-quarter of the posterior limb of the internal capsule containing frontothalamic and frontopontine fibers, which if compromised can result in mental changes. Fig. 1. A parasagittal section of human brain 14.5 mm from the midline; crossing the target center in the average case. Below is a drawing of this section with the superimposed outline of the third ventricle (each division of the grid is 1 mm). The usual trajectory is

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Takashi Iwabuchi and Jiro Suzuki

the right internal auditory canal was evident in the film. Roulette tomograms taken in the sagittal plane showed tumor outline 5 mm to the right of the center. In the contralateral 5 mm plane, the outline of the pons was visible, while the outline of the tumor was not seen. Comment In the usual tomogram, motion of the tube and film is linear or in an arc; this results in a blurred shadow and makes detailed demonstrations impossible. Several devices with long complexed trajectories or orbits have been created in an effort to eliminate this blurring shadow

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David Yashon, John A. Jane and Robert J. White

. Many patients were returned to a useful existence and even “walked” by physiatric methods. Eleven patients, eight of whom had had a laminectomy, died within post injury ranges of 5 days to 5 years. The presence or absence of spinal fluid blood, dynamic block, or dermatomal level of injury could not be correlated with survival even when divided into short-term or long-term categories. Trajectory and final position of metallic fragments or extent of bony fragmentation could not be correlated with survival. In a few instances, in spite of careful radiographic survey

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Donald P. Becker, Cavett M. Robert Jr. and John Seelig

used for stereotaxic radiofrequency lesion generation. Cerebral lesions with a significant impedance alteration along a trajectory can be precisely located and biopsied through the carrying probe. A specific impedance change was noted in five of five neoplastic and two of five non-neoplastic lesions studied. References 1. Becker , D. P. , and Nulsen , F. E. Control of lesion making in percutaneous cordotomy. J. Neurol. Neurosurg. Psychiat. , 1968 , 31 : 87 . Becker , D. P., and Nulsen , F. E. Control of lesion making in

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Paul J. Pitlyk, Sidney Tolchin and William Stewart

right angles to the missile trajectory and is responsible for the shatter effect (linear and diastatic fractures) frequently seen in the skull films of such victims. 6, 7 Missiles of lower velocity usually do not produce such fractures, yet a shock wave of lesser amplitude is still transmitted. This shock pattern is thought to proceed in a sine wave fashion producing cerebral edema in alternating degrees of intensity as it proceeds radially from the missile path. 10 Strung out along the narrow wound tract of pulped brain are the contaminants alluded to above