Advances in Stereotactic and Functional Neurosurgery 6

Local interstitial radiation therapy of intrinsic and inaccessible brain tumors is confronted with two major problems: 1. The tolerance of normal brain tissue, which is usually involved in local tumor irradiation, i.e. perifocal white matter edema and demyelinating effects, is crucial. 2. Data on radiation effects of implanted radioactive sources on neoplastic tissue, i.e. data on the radiosensitivity and on the biology of tumors, are still widely unavailable. In clinical practice the dose with which to achieve a given volume of tumor necrosis is roughly estimated. This report deals with the experimental findings of Iodine-125 and Iridium-I92 permanent implants in healthy and neoplastic brain tissue. Our own experimental findings are correlated with experimental data on Yttnul11-l)O irradiation from the literature. The study is directed to collect data on the tolerance non-tumoral brain tissue and to attempt to establish a dose-response relationship. Morphologic Changes in the Dog Brain Following Interstitial Iodine-125 Irradiation Iodine-I25 seeds (manufactured by 3 M Company, St. Paul, M. N.) with an activity of 3.55 mCi were permanently implanted under stereotactic conditions into the subcortical white matter of the gyrus coronalis of the left hemisphere in 6 beagle dogs. One animal with a non-radioactive seed implanted under similar operative conditions served as a control. The animals were allowed to survive 25, 46, 71, 94, 248, 368 days, respectively, after the implantation. The control animal survived 46 days. A detailed description of the experimental procedure is given elsewhere 16. 17.

Section I. Epilepsy.- 1. Diagnosis.- A. Introduction.- Progress in Diagnosis in View of Surgical Treatment of the Epileptic Patient.- B. Reports.- Localizing Value of the Clinical Manifestations of the Partial Seizures.- Automatic Analysis of Electrocerebral Activity.- Changes of Energy Metabolism and Regional Cerebral Blood Flow Studied by Positron Emission Tomography in the Interictal Phase of Partial Epilepsy.- C. Communications.- Eye Movements and Occipital Seizures in Man.- The Epileptic Seizure with Origin in Frontal Lobe: A Complex Problem for Surgery.- Techniques for the Analysis of Spike Trains in the Human Central Nervous System.- Shape Factor Intensity (SFI) Analysis of EEG of Patients Treated Surgically for Epilepsy.- Stability of Interictal Spike Rate as an Index of Local Epileptogenicity. A Study Based on Computer Analysis.- Computerized Analytic Study of Stability of Interictal Spike Rate.- Chronic Burr-Hole ECoG and SEEG in the Assessment of Surgical Treatment for Epilepsy.- Tridimensional Biomagnetic Localization of Epileptic Foci.- Stereotactic Methodology in Epileptic Patients with Hemispheric Astrocytoma.- Depth Recording and Neuropathological Aspects in Symptomatic Tumoral and Non Tumoral Epilepsy.- Positron Emission Tomographie Studies in Focal Epilepsy.- Influence of Pregnane Derivates on Metabolism of the Brain and Epileptic Activity in Man.- Correlations Between rCBF and Computerized EEG in Temporal Lobe Epilepsy.- Study of the Role of Defence Mechanisms in Patients with Epilepsy to the Purpose of Neurosurgical Treatment and Rehabilitation.- 2. Surgical Treatment.- A. Introduction.- Indications, Advantages and Limits of the Different Rationales of Surgical Treatment of Epilepsy.- B. Communications.- Temporal Lobectomy for Epilepsy in the Patients with Ipsilateral Extratemporal Brain Lesion.- Surgical Management of Partial Epilepsies: A Critical Evaluation of Electrical, CT Scan, and Pharmacological Studies of the Milan Series.- Excision of Two and Three Independent and Separate Ipsilateral Potentially Epileptogenic Cortical Areas.- Additional New Approach in Treatment of Temporal Lobe Epilepsy.- Caudate Nucleus Stimulation Düring Epilepsy Treatment.- The Reduction of Seizures in Cerebral Palsy and Epileptic Patients Using Chronic Cerebellar Stimulation.- Section II. Cerebral Tumours.- Introductory Lecture.- Morphologie Evaluation of Stereotactic Brain Tumour Biopsies.- 1. Stereotactic Biopsy.- Some Correlations Between Histological and CT Aspects of Cerebral Gliomas Contributing to the Choice of Significant Trajectories for Stereotactic Biopsies.- Stereotactic Sampling Biopsies in a Series of 268 Consecutive Cases—Validity and Technical Aspects.- The Reliability of Stereotactic Biopsy.- Intra-Encephalic Stereotactic Biopsies (309 Patients/318 Biopsies).- Diagnostic Accuracy and Multimodal Approach in Stereotactic Biopsies of Deep Brain Tumours.- Stereotactic Biopsy of Brainstem Tumors.- Stereotactic Biopsy of Intracranial Processes.- A Global 3-D Image of the Blood Vessels, Tumour and Simulated Electrode.- Computer Assisted Stereotactic Biopsies Utilizing CT and Digitized Arteriographic Data.- Stereo-EEG Contribution to the Three-Dimensional Definition of the Hemispheric Astrocytomas.- Depth-EEG in Stereotactic Biopsy.- A Simple Method for the Growth of Cell Cultures from Small Biopsies of Brain Tumours Taken Düring CT-directed Stereotactic Procedures.- Tissue Mechanical Resistance Measurements and Records in Stereotactic Biopsy Procedures.- Preliminary Experiences with Intraoperative Ultrasonography in Cerebral Tumour Biopsy.- CT Assisted Stereotactic Biopsy of Deep Cerebral Lesions and the Results.- Observations with the Utilization of the Brown-Roberts-Wells Stereotactic System in the Management of Intracranial Mass Lesions.- CAT Scan-directed Stereotactic Brain Biopsy: With Template Produced by Computer Graphics.- 2. Stereotactic Focal Irradiation.- I. Effects on Tumour and Brain.- Experimental Data on Early and Late Morphologie Effects of Permanently Implanted Gamma and Beta Sources (Iridium-192, Iodine-125 and Yttrium-90) in the Brain.- Morphology of Intracranial Tumours and Adjacent Brain Structures Foliowing Interstitial Iodine-125 Radiotherapy.- Radiolesion versus Recurrence: Bioptic Data in 39 Gliomas After Interstitial, or Combined Interstitial and External Radiation Treatment.- Response of Human Malignant Gliomas and CNS Tissue to 125I Brachytherapy: A Study of Seven Autopsy Cases.- Radiation Damage to Normal Canine Brain Induced by Radiation from Interstitially-Implanted 125I Sources.- An Animal Tumor Model for the Study of the Radiation Biology of 125I Interstitial Brachytherapy.- Pathological Findings in Acoustic Neurinoma After Stereotactic Irradiation.- II. Clinical Results.- Indication and Results of Stereotactic Curietherapy with Iridium-192 and Iodine-125 for Non-resectable Tumours of the Hypothalamic Region.- Colloidal Rhenium-186 in Endocavitary Beta Irradiation of Cystic Craniopharyngiomas and Active Glioma Cysts. Long Term Results, Side Effects and Clinical Dosimetry.- Results of Stereotactic Intracavitary Irradiation of Cystic Craniopharyngiomas. Comparison of the Effects of Yttrium-90 and Rhenium-186.- Combined Interstitial and External Irradiation of Gliomas.- Interstitial and Combined Interstitial and External Irridiation of Supratentorial Gliomas. Results in 61 Cases Treated 1973-1981.- Brachytherapy with Removable Iodine- 125 Sources for the Treatment of Recurrent Malignant Brain Tumours.- Long-term Results of Stereotactic Interstitial Curietherapy.- Stereotactic Radiosurgery in Acoustic Neurinoma.- III. Technical Aspects.- Preoperative Computer Determination of Interstitial Iridium-192 Source Placement into CNS Tumour Volumes.- Hyperselective Encephalic Irradiation with Linear Accelerator.- Concluding Remarks of the Moderator.- Progress and Problems in Tumour Stereotaxis.- Section III. Pain.- Introductory Lecture.- The Suggested Mechanisms of Chronic Pain and the Rationale of Neurosurgical Treatment.- I. Pelvic Cancer Pain (Somatogenic Pain).- Pros and Cons of Different Approaches to the Management of Pelvic Cancer Pain.- Personal Experience with Intrathecal Morphine in the Management of Pain from Pelvic Cancer.- The Role of Cervical Percutaneous Antero-lateral Cordotomy in Malignant Low-back Pain.- Stereotactic High Cervical Extralemniscal Myelotomy for Pelvic Cancer Pain.- Rostrai Stereotactic Mesencephalotomy in Treatment of Cancer Pain; a Survey of 40 Treated Patients.- II. Plexus Avulsion Pain (Neurogenic Pain).- High Frequency Coagulation of Dorsal Root Entry Zone in Patients with Deafferentation Pain.- Epidural versus Thalamic Stimulation for the Management of Brachial Plexus Lesion Pain.- III. Other Topics on Pain.- One Possible Mechanism of Central Pain. Autokindling Phenomenon on the Phantom Limb or Sensory Loss Oriented Patients.- Tic Douloureux Treated by the Injection of Glycerol into the Retrogasserian Subarachnoid Space. Longterm Results.- Neurophysiological and Ultrastructural Study of the So-called Microcompression of the Gasserian Ganglion in the Treatment of Trigeminal Neuralgia.- Longterm Results of Stimulation via an Implanted Gasserian Electrode for Atypical Trigeminal Pain.- Radiofrequency Electrical Stimulation of the Gasserian Ganglion in Patients with Atypical Trigeminal Pain. Methods of Percutaneous Temporary Test-stimulation and Permanent Implantation of Stimulation Devices.- Results to Explain the Mechanism of Certain Chronic Pain Syndrome with the Method of Evoked Sensory Potentials and Power Spectra Density Analysis.- Deep Brain Stimulation in Chronic Pain Syndromes.- Preliminary Results of Specific Thalamic Stimulation for Deafferentation Pain.- Effect of Electrical Stimulation of Periaqueductal Gray and Septal Area on Beta-Endorphin Plasma Levels in a Model of Deafferentation Pain. Experimental Study in Rats.- Chronic VPM Thalamic Stimulation in Facial Anaesthesia Dolorosa Following Trigeminal Surgery.- Recent Progress in the Treatment of Trigeminal Neuralgia: Glycerol into the Trigeminal Cistern and Percutaneous Gasserian Compression by Means of Fogarty’s Catheter.- Controlled Radiofrequency Thermocoagulation of Trigeminal Ganglion in the Treatment of Trigeminal Neuralgia, Hemifacial Spasm, and Facial Neuralgia.- Percutaneous Thermolesion of the Glossopharyngeal Nerve: Results and Anatomo-physiological Considerations.- Percutaneously Implantable Chronic Electrode for Radiofrequency Stimulation of the Gasserian Ganglion. A Perspective in the Management of Trigeminal Pain.- The Use of Highly Detailed Three Dimensional Neuroanatomical Images in the Placing of Cerebral Stimulating Electrodes for Pain.- Section IV. Miscellaneous.- Quantification of Thalamic EEG by the Shape-factor Intensity (SFI) Method.- Deep Brain Stimulations in Cases of Prolonged Post-traumatic Unconsciousness.- Selective Posterior Rootlet Section in the Treatment of Spastic Disorders of Infantile Cerebral Palsy: Immediate and Late Results.- Clinical and Electrocardiographic Improvement of Ischaemic Heart Disease After Spinal Cord Stimulation.- Third Ventricular Width and Thalamo-capsular Laterality.- Stereotactic Cryosurgery in a CT Scanner.- A New Stereotactic Instrument Which Can be Used in Conjunction With Open Surgery.- A Portable Computerized Tomographie Method for Tumour Biopsy.- Clinical Application of an Original Stereotactic Apparatus.- Advanced Intraoperative Imaging for Stereotaxis. The Surgical CT Scanner.- Functional Stereotactic Surgery Utilizing CT Data and Computer Generated Stereotactic Atlas.