The inferior parietal lobule (IPL) of the monkey is the homologous region to the supramarginal and angular gyri in man, subserving language and related cortical functions. We have examined specific zones of the IPL by injecting eight monkeys with retrogradely transported HRP, and located the positive cells in the thalamic sections with the assistance of an X-Y plotter and reference to the atlas of Olszewski ('52). Projections to the IPL were found in the following thalamic nuclei: Anterior (Anterior Medial, Anterior Ventral) ; Lateral (Ventral Anterior, Ventral Anterior magnocellularis, Ventral Lateral caudalis, Pulvinar oralis, medialis, lateralis and inferior, Lateral Posterior and Lateral Dorsal) ; Medial (Medialis Dorsalis densocellularis, parvocellularis, and multiformis) ; Midline and Intralaminar (Centralis densocellularis, Centralis lateralis, Centralis inferior, Centralis superior lateralis, Subfascicularis parvocellularis, Paracentralis and Parafascicularis) ; and Posterior (Limitans, Suprageniculatus and Geniculatus Medialis magnocellularis) .A major projection to the superior portion of the IPL was from the anterior nuclei and Paracentralis of the intralaminar group. Ventralis Lateralis and oral Pulvinar projected primarily to the anterior-inferior portion of the IPL, whereas Lateral Posterior projected most strongly to the anterior and superior portion. The major projection of the lateral Pulvinar was to the mid-superior portion of the IPL and to area 19. The projections of the inferior Pulvinar were heaviest to area 19, but there was some overlap in the mid-superior portion of the IPL with the medial and lateral Pulvinar. The major projection from the posterior thalamic nuclear complex was to the mid-IPL. The heterogeneous input from the thalamus to the IPL was not anticipated on the basis of prior anterograde or retrograde degeneration studies, and suggests that classical subdivisions of specific and associational thalamic nuclei should be revised with the axonal transport methods of study.Cerebral hemisphere connection studies have demonstrated convergence of input to certain zones in the frontal, parietal, temporal and occipital cortex (Pandya and Kuypers, '69; Jones and Powell, '70). These zones lie outside the primary receptive areas and are associative in nature. We have studied in the rhesus monkey the anatomical relationships of the clinically important representative of associational cortex, the inferior parietal lobule (IPL). This region has been designated area 7 by Brodmann ('09) and P F and PG by von Bonin and Bailey ('47). IPL lesions in humans can produce serious deficits in language, calculation, right-left and spatial orientation, figure construction, awareness of body parts and sensory stimuli, tasks involving sensory discrimination and the ability to recognize self impairment (Critchley, '53; Geschwind, '65).Microelectrode recording studies in the monkey have shown visual, auditory and sensory convergence to area 7 neurons (Hyvarinen and Poranen, '74). The subcortical rela...
Posttraumatic spasticity severely impedes rehabilitation potential and nursing care. Treatment of severe spasticity has included medical therapy, spinal cord ablative procedures, anterior and posterior root lesions and peripheral denervations, and tendon releases. Open rhizotomy and percutaneous radiofrequency rhizotomy have achieved good results. We prospectively studied 25 patients with severe spasticity to assess the efficacy of percutaneous radiofrequency rhizotomy. All or most of the prospectively identified goals were accomplished in 24 of the 25 patients, with improvement persisting during an average follow-up period of 12 months. The improvement due to decreased tone was much greater than the improvement due to increased range of motion.
Interhemispheric subdural hematomas are rare. Bilateral interhemispheric subdural hematomas in a patient with a ventriculoperitoneal shunt for hydrocephalus were diagnosed by computerized tomographic (CT) scan after mild head trauma. The value of CT scanning, the clinical presentation and treatment, and a review of the literature are presented.
We report two patients who underwent orbital exploration yielding the diagnosis of sclerosing orbital pseudotumor. The presenting symptoms were exophthalmos, visual loss, abnormal ocular mobility, and ocular pain. Computed tomographic (CT) scans showed masses in the orbital apex. Steroids were ineffective. Orbital pseudotumor is a heterogeneous diagnostic category of lymphoid infiltrations of the orbit with a wide spectrum of pathological conditions and intraorbital locations. The clinical presentation typically includes the sudden onset of pain, diplopia, lid edema, and exophthalmos. Visual loss is uncommon. Most cases resolve spontaneously or respond to steroid treatment. Although fibrosis may be a prominent histological finding, the literature contains little information concerning its significance. We discuss the evidence for considering the sclerosing pseudotumors to be a significant variant with unique clinical behavior. Although features suggestive of pseudotumor were present in our case, the presence of visual loss and an apical mass shown on the CT scan led to the presumptive diagnosis of tumor and exploratory operation. Neurosurgeons should be aware of this entity as a cause of visual loss and orbital mass. Proper suspicion may in some cases permit transorbital biopsy and avoid craniotomy, inasmuch as operation is of no therapeutic benefit in this disease.
After radiotherapy, 20 patients, 18 with documented progression of malignant glioma and 2 with Grade II astrocytoma, received a total of 52 courses of intracarotid 1,3-bis-(2-chloroethyl)-1-nitrosourea (BCNU) at a dose of 150 mg/m2 dissolved in 5% dextrose in water. The patients were treated at 6-week intervals for a maximum of five courses of chemotherapy per patient. Response to treatment was analyzed on computed tomographic scans by measuring the volume of the enhancing tumor and any central low density. From these data, tumor doubling times ranging from 110 to 968 days were obtained. An 11 to 60% reduction in enhancing tumor volume was noted in 8 patients, 2 of whom had a greater than 50% decrease in tumor volume. One patient had no change in tumor volume 110 weeks after the initiation of BCNU chemotherapy. Four patients had tumor in more than one vascular territory; tumor growth was arrested in the perfused territory, but continued in the nonperfused area. In 1 of the 4 patients, tumor also grew along a shunt catheter tract and spread over the surface of the ipsilateral hemisphere. One patient developed clinically asymptomatic leukoencephalopathy after five courses of BCNU. Two patients had postradiation leukoencephalopathy before BCNU treatment. Seventeen patients had peritumoral low density with mass effect after BCNU; thus, the true incidence of BCNU-related leukoencephalopathy could not be determined. All patients experienced transient unilateral orbital pain during the infusion and scleral erythema that lasted for several hours afterward. Loss of vision was noted in 2 patients, although it seemed to be related to the therapy in only 1 patient.(ABSTRACT TRUNCATED AT 250 WORDS)
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