Early Experiences with Ultrasonic Irradiation of the Pallidofugal and Nigral Complexes in Hyperkinetic and Hypertonic Disorders

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I. THE PROBLEM AND EARLY APPROACHES

In 1939 a series of surgical investigations directed at the basal ganglia in an effort to alleviate the hyperkinetic and hypertonic features of parkinsonism, chorea, athetosis and dystonia was initiated by the senior author39,40 of the present paper. Taken singly and in combination, the structures interrupted or extirpated in the pre-World War II series of 16 patients subjected to such operations included the caudate head, the ansa lenticularis, the anterior limb of the internal capsule, the oral third of the globus pallidus and the oral third of the putamen.41,42

Article Information

Division of Neurosurgery, State University of Iowa, Iowa City, Iowa.

Biophysical Research Laboratory, University of Illinois, Urbana, Illinois.

© AANS, except where prohibited by US copyright law.

Headings

Figures

  • View in gallery

    Stage 1 of operation. Patient's head secured by four pinions “seated” in small superficial cranial burr holes at frontal and occipitoparietal sites. Adjustments on each post (P1–P4) supporting the pinions can be set by micrometer readings. This permits tridimensional spatial repositioning of each pinion for duplicating the position of the patient's skull with respect to the head holder. Note pointer (Ph) carried by positioning system(s) mounted on head-holder stereotactic apparatus. A ventricular cannula, the tip of which rests in the anterior horn of the uppermost lateral ventricle, is visible.

  • View in gallery

    Stage 1 of operation. First lateral radio-opaque ventriculogram showing coordinate lines relating roentgen-ray beam position to stereotactic apparatus and head position as projected on the film. The shadow of the pointer, carried by the head-holder positioning system, appears on the film. Its tip serves as an initial “bench mark” used for evaluating the longitudinal and vertical coordinates (with respect to the head holder) of the reference position in the patient's brain. The intercommissural line has been drawn between the positions of perpendicular projection of the anterior and posterior commissures. The longitudinal and vertical projections of the reference point (in this case, a “central” position in the ansal region) are computed. The position of perpendicular projection of the pointer tip's shadow is now revised to make it coincide with the reference point. The pointer is stereotactically moved to the new position and the roentgenogram is repeated.

  • View in gallery

    Stage 1 of operation. First anteroposterior radio-opaque ventriculogram, showing coordinate line relating roentgen-ray beam position to stereotactic apparatus and head position as projected on the film. The shadow of the pointer, carried by the head-holder positioning system, appears on the film. Its tip serves as an initial “bench mark” used for evaluating the lateral coordinate (with respect to the head holder) of the reference position (midline of the third ventricle) in the patient's brain. Computations are similar to those indicated for Fig. 2 and after the pointer is moved to the new position a second roentgenogram is taken.

  • View in gallery

    Stage 2 of operation. The hopper, partly filled with degassed physiological saline solution, is in place. The dura mater and muscle flap (dark shadow) can be seen at the depth of the hopper. (The coils within the hopper provide a continuous flow of water for the purpose of thermo-regulation of the saline solution at near body temperature.) The multibeam ultrasound transducer is being lowered into position to place its common focus in the desired site of the target structure. In this position, the lenses of the irradiator are immersed in the saline solution. (Only three of the four sound sources can be seen in this view.)

  • View in gallery

    Approximate site (illustrated by black spindle) in the superior medial neighborhood of the substantia nigra at which the first ultrasonic exposure in each of the five “nigral” irradiations was made. Irradiation here was promptly followed by reduction (or in some cases abolition) of tremor and by decreased rigidity. Additional exposures were placed in neighboring sites in coronal planes l½ to 2 mm. anterior and posterior to the first site and in some cases more than one exposure was placed in the same coronal plane. Other sites, at which lesions were placed in the border zone and within the substantia nigra, are illustrated semidiagrammatically by the white spindles of the figure. However, the configuration illustrated does not correspond to the array of exposures produced in any patient since the brain section of the figure does not lie in a coronal plane and so consequently the long axes of neighboring sites of exposure could not lie in the plane of this section. It should not be assumed that a complete set of four lesions, in the form of the array schematically illustrated here, was produced in all coronal planes in which lesions were placed.

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