The Pioneering and Unknown Stereotactic Approach of Roeder and Orthner from Göttingen. Part II: Long-Term Outcome and Postmortem Analysis of Bilateral Pallidotomy in the Pre-Levodopa Era.

Before the advent of levodopa, pallidotomy was initially the most effective treatment for Parkinson disease, but it was soon superseded by thalamotomy. It is widely unknown that, similar to Leksell, 2 neurologists from Göttingen, Orthner and Roeder, perpetuated pallidotomy against the mainstream of their time. Postmortem studies demonstrated that true posterior and ventral pallidoansotomy sparing the overwhelming mass of the pallidum was accomplished. This was due to a unique and individually tailored stereotactic technique even allowing bilateral staged pallidotomies. In 1962, the long-term effects (3-year follow-up on average) of the first 18 out of 36 patients with staged bilateral pallidotomies were reported in great detail. Meticulous descriptions of each case indicate long-term improvements in parkinsonian rigidity and associated pain, as well as posture, gait, and akinesia (e.g., improved repetitive movements and arm swinging). Alleviation of tremor was found to require larger lesions than needed for suppression of rigidity. No improvement in speech, drooling, or seborrhea was observed. By 1962, the team had operated 13 patients with postencephalitic oculogyric crises with remarkable results (mean follow-up: 5 years). They also described alleviation of nonparkinsonian hyperkinetic disorders (e.g., hemiballism and chorea) with pallidotomy. The reported rates for surgical mortality and other complications had been remarkably low, even if compared to those reported after the revival of pallidotomy by Laitinen in the post-levodopa era. This applies also to bilateral pallidotomy performed with a positive risk-benefit ratio that has remained unparalleled to date. The intricate history of pallidotomy for movement disorders is incomplete without an appreciation of the achievements of the Göttingen group.

Neurosurgery in India: an overview.

This overview of neurosurgery in India during the last six decades gives a holistic perspective of the phenomenal advances made. Neurosurgical education, the change in clinical spectrum of diseases and their presentation, evolution of various subspecialties and societies, the state of research, the issues peculiar to India, including the urban-rural health divide, the increasing role of information and communication technology in neurosurgery, and the gradual but definite global recognition of Indian neurosurgery will be addressed.

The peripeduncular nucleus: a novel target for deep brain stimulation?

The pedunculopontine nucleus, a promising new target for deep brain stimulation in Parkinson's disease, straddles the pontomesencephalic junction--unfamiliar territory to most functional neurosurgeons. This contribution reviews the anatomy of the pedunculopontine and peripeduncular nuclei. Given the reported findings of Mazzone et al. in NeuroReport, the authors postulate that the peripeduncular nucleus might be of previously unexpected clinical relevance.

Visualization of thalamic nuclei on high resolution, multi-averaged T1 and T2 maps acquired at 1.5 T.

The ability to differentiate noninvasively between the primary nuclear divisions of the thalamus has immediate clinical applicability for surgical planning and guidance of functional stereotactic procedures. Comparison of prior qualitative magnetic resonance imaging (MRI) studies carried out at field strengths of 1.5 and 4 Tesla have revealed contrast within the thalamus that varies with field strength, suggesting possible differences in the inherent T1 and T2 relaxation times of the constituent nuclei. We investigate this hypothesis through acquisition of high-resolution, multi-averaged deep-brain T1 and T2 maps of a healthy volunteer. Fourteen nuclei were identified using their center-of-mass coordinates (in Talairach space) and average T1 and T2 values obtained from regions of interest placed within each. Results from this analysis revealed significant differences in T1 and T2 between the nuclei with a T1 range from 700 to 1,400 ms and a T2 range from 89 to 122 ms, allowing visual discrimination between the major nuclei groups. Furthermore, the high-resolution images showed distinct borders of T1 and T2 hypointensity surrounding each nucleus, revealing structure not reported previously. These results confirm our hypothesis and demonstrate the potential high-resolution quantitative imaging for nucleus visualization and surgical planning.

Deep brain stimulation for movement disorders.

Movement disorders remain the primary indication for the use of intracranial neurostimulation techniques. This review will discuss the history of this technology as well as the mechanisms of action, current clinical indications, and future prospects for the treatment of movement disorders.

[Stereotaxic treatment in Parkinson's disease]. / Le traitement stéréotaxique de la maladie de Parkinson.

For the stereotactic treatment of Parkinson's disease, the target is usually located in the thalamus; this point is related to nearby structures (third ventricle). Then the position is controlled by electrophysiological recordings. The lesion of the target results in permanent suppression of the contralateral tremor and/or rigidity but it changes neither the course of the disease nor the akinesia. Owing to the risk of dysarthria with bilateral procedures, the main indication for surgery is parkinsonism with unilateral tremor or rigidity. Particularly interesting for the future are the possibilities of stimulation through implanted chronic electrodes.

The future role of neurosurgery in medicine.

Illustrated by several examples from the past it is demonstrated how difficult it is to predict future developments in neurosurgery. Several determinants can be recognized as exerting a positive or a negative influence in this respect. Careful observation of unexpected events and consequent consideration in combination with a spiritual independency, are aspects which will contribute in a positive way. The reverse will unavoidably lead to abolition of new ideas and concepts. Authority in a personal as well as in an impersonal way, may act as a negative determinant. This aspect is illustrated by some examples regarding the phenomenon of the "medical mandarin" as a personal authority, and the irrational adherence to paradigms as an impersonal one. Based upon recent experiments new ways for neurosurgical activities are indicated, concerning 1st transplantation of fetal central nervous tissue and of adrenal medullary tissue, and 2nd deep long-term stimulation of the beta endorphin-serotonin system for the control of chronic pain.