Invasiveness invitro versus clinical evolution of primary and secondary brain-tumors.

Cells of 56 primary cell cultures derived from primary and secondary brain tumours were confronted in vitro with host tissue, embryonic chick heart fragments (PHF). The evolution of the confrontation was followed for one week. Histological analysis of the confrontations demonstrated two different patterns. (i) Survival of host tissue and tumour derived cells without invasion of the last ones into the host. (ii) Invasion of tumour derived cells into the host tissue followed by replacement of the chick heart tissue. Invasion into the host tissue was observed only in the confrontations with primary cell cultures originating from malignant and metastatic tumours. The invasive characters in vitro of primary cell cultures correlated with the malignancy of the tumour in vivo.

An MR protocol for presurgical evaluation of patients with complex partial seizures of temporal lobe origin.

PURPOSE: To find an optimal diagnostic protocol for the presurgical MR evaluation of patients with temporal lobe epilepsy. METHODS: MR imaging in 14 healthy subjects and 25 consecutive patients with temporal lobe epilepsy was performed in paracoronal sections perpendicular to the hippocampi with T1-weighted inversion recovery and T2 weighting. Volume measurements of the hippocampus/amygdala complex were performed and a multiecho sequence yielded T2-calculated images. RESULTS: Hippocampal disease was seen in 22 of 25 temporal lobe epilepsy patients on paracoronal T1-weighted inversion recovery images. Four had bilateral abnormalities. Characteristic for hippocampal disease were features such as volume loss, decreased signal, and loss of internal morphology. Only 17 of 25 patients demonstrated hippocampal pathology on T2-weighted images, and in one patient this was bilateral. Patients with only minimal structural loss on T1-weighted inversion recovery had normal T2-weighted images. T2 calculation was no more sensitive than visual assessment on the T2-weighted images. Volume measurements were normal in one patient and misleading in two patients. Lateralization, as compared with clinical and electroencephalographic findings, was most confidently done with paracoronal T1-weighted inversion recovery images and volume measurements. CONCLUSIONS: An optimum MR protocol for temporal lobe epilepsy patients is proposed. Its essential feature is that the hippocampus be evaluated by paracoronal T1-weighted inversion recovery images and volume measurements. T2-weighted imaging can be omitted.

Invasiveness of primary and secondary brain tumors in vitro correlated with clinical results.

One hundred fifty-one tumor fragments were collected in the neurosurgical operating amphitheater immediately after removal. Small tumor fragments were transferred into culture flasks and cultured until a confluent monolayer was formed by the outgrowing cells. Flaps of these cell monolayers were mechanically scraped from the culture flasks and confronted with embryonic chick heart tissue in vitro. The evolution of the confrontations was followed for a week. Histological analysis of the confrontations demonstrated three different morphological patterns of interaction between the heart tissue and the tumor-derived cells: 1) progressive engulfment of the tumor-derived cells by the heart tissue (Type I), 2) survival of both the heart tissue and the tumor-derived cells (Type II), and 3) progressive replacement of the heart tissue by tumor-derived cells (Type III). The replacement of the heart tissue by tumor-derived cells was only observed in cells originating from malignant tumors that were invasive and metastatic in vivo. Thus, invasiveness in confrontation culture is correlated with malignancy in vivo.

Invasion of human brain tumors in vitro: relationship to clinical evolution.

Embryonic chick heart fragments were confronted in vitro with cells from 26 freshly resected human brain tumors. The tumor-derived cells were scored according to their survival and invasiveness. Four different responses were observed: disintegration of the tumor-derived cells (Type I); survival of cells without progressive engulfing or invasion of the heart fragment (Type II); initial encircling of the heart fragment followed by invasion (Type III); and massive invasion on initial contact (Type IV). Pattern Type III or IV was seen in 11 of 14 preparations derived from malignant tumors, and pattern Type I or II was seen in seven of 10 preparations derived from benign tumors. These results suggested that "classical malignancy," based upon the histological classification and the degree of spread in vivo, correlated with invasiveness in vitro.

Transesophageal echocardiography: a simple method for monitoring the patency of ventriculoatrial shunts. Technical note.

A new method for evaluating the patency of a ventriculoatrial shunt is described, and early experience with it is reported. Transesophageal echocardiography can demonstrate a cerebrospinal fluid leak in the right atrium through the atrial tip of a shunting device. This capability was an incidental discovery, and since then the accuracy of the technique in evaluating the patency of a ventriculoatrial shunt has been prospectively studied in 20 observations of 16 patients. The method proved to be accurate in 90% to 100% of cases. It is concluded that transesophageal echocardiography offers a rapid and accurate assessment of ventriculoatrial shunt function, is well tolerated, and is easy to perform.

Spinal cord stimulation in chronic pain: evaluation of results, complications, and technical considerations in sixty-nine patients.

Sixty-nine patients undergoing spinal cord stimulation (SCS) were studied for a period of up to 8 years. Indications, implantation techniques, and stimulation systems are presented in this article. Pain-suppressor effects of SCS are reviewed, assessing the clinical efficacy over time as well as complications with the stimulation device. Immediately following implantation, inadequate pain relief was noted in 20% of the patients. Decrease of the efficacy of pain alleviation occurs during the first 3 years after implantation. Most failures are noted in patients presenting with failed back surgery. This study also demonstrates that SCS systems should offer the capability of both monopolar and bipolar stimulation modes by the use of multipolar electrodes.

Spinal cord stimulation in chronic pain therapy.

Spinal cord stimulation was undertaken in 45 patients referred to the University Hospital in Ghent. Failed back surgery was the major indication for implantation. Raynaud's phenomenon, causalgia, polyneuropathy, phantom limb pain, and diverse causes were the other indications. Before neurosurgical implantation of the system, a percutaneous epidural trial procedure was performed. The efficacy of the implanted stimulation system was estimated by considering the use of medication and the patients' personal appreciation of the obtained pain relief. Thirty-five patients experienced very good pain relief. Only two patients needed further narcotic analgesics. Eight patients stopped using the stimulation system. To ensure good results, strict selection criteria and many surgical reinterventions seemed to be necessary. Although spinal cord stimulation is a nonablative technique, many complications may occur.

Megadolichobasilar anomaly, basilar impression and occipito-vertebral anastomosis.

The authors describe a case of a megadolichobasilar anomaly associated with basilar impression, bilateral megadolichocarotid arteries and an occipito-vertebral anastomosis. The concurrence of these anomalies lends support to the hypothesis that congenital factors play a part in the origin of the megadolichobasilar anomaly.

Spinal epidural hematoma without lesion of the spine. Report of 4 cases.

The authors report 4 cases of spinal epidural hematoma without a lesion of the spine. The medical literature relating to this subject is reviewed with special reference to the pathophysiology of the bleeding. There are arguments in favor of the venous origin as well the arterial origin of the bleeding. As far as recovery following surgical treatment is concerned, the history of our cases confirms the opinion that the prognosis depends on two factors: the delay between onset of symptoms and operation and the severity of the neurological deficit.

Brain abscess after esophageal dilatation for stenosis.

The case is presented of a 28-year-old female with a brain abscess after esophageal dilatation for stricture, secondary to an acute necrotizing esophagitis. Other causes of brain abscess were excluded. To our knowledge this is the first documented case of brain abscess after dilatation for esophageal stricture in adult life. Some reports in the pediatric literature have been published previously.

Aneurysmal bone cysts in the cranial vault and base of skull.

Three cases of aneurysmal bone cyst of the skull are reported. The localization in the base of the skull (two cases) is extremely rare and simulates a space-occupying intracerebral lesion. The clinical and microscopic findings, and their significance for the differential diagnosis from malignant brain tumors, are described.

Intramedullary spread of a cerebral oligodendroglioma.

A case of intramedullary spinal metastasis of a cerebral oligodendroglioma is presented. This exceptional presentation, as well as the routes of dissemination, are discussed by review of the literature.

Invasiveness in in vitro and clinical evaluation of meningiomas.

Fragments of freshly isolated human meningiomas were cultured in vitro to form cell monolayers. These monolayers were confronted with embryonic chick heart fragments in vitro for 1, 2, 4, and 7 days. Microscopically, three different histological patterns were observed. Type I included necrotized meningial cells; type II presented surviving meningial cells; type III included meningial cells that had invaded the host tissue. The clinical analysis included the histopathological diagnosis, the macroscopic situation at surgical intervention, and the follow-up with or without recurrence. Correlation between these clinical parameters and the in vitro results demonstrated that type III confrontations correlated with macroscopic infiltration in the brain parenchyma and tumor recurrence. Invasiveness in vitro was seen in two anaplastic and two transitional meningiomas.

A multipurpose cerebral endoscope and reflections on technique and instrumentation in endoscopic neurosurgery.

We discuss our experiences concerning our cerebral endoscope with reflections on various techniques used since 1986. During this time we have had experience with four prototypes. This minimal invasive procedure has been successful to a certain extent both in paediatric and adult patients, stereotactically and by freehand method or both. Further modification for flexibility and manipulation of the optic element is under development.

Endoscopic diagnosis and treatment of para- and intra-ventricular cystic lesions.

Different cystic lesions can be located in or around the ventricular system, eventually causing hydrocephalus. Twenty-one patients are described where endoscopic intervention, mainly large fenestration towards the ventricular cavity, has been performed. This treatment can sometimes replace open surgery or extracranial shunting. Most rewarding are the arachnoid and ependymal intra- and paraventricular cysts. With careful and adequate endoscopic technique this procedure is safe and much less invasive than other methods described.

Epilepsy surgery in Belgium, the Flemish experience.

Between January 1992 and June 1995, 160 patients were presurgically evaluated for medically refractory epilepsy by the Epilepsy Monitoring and Surgery Team at the University Hospital of Gent. All these patients underwent a comprehensive presurgical evaluation, including extensive neurological history and examination, video-EEG monitoring of interictal EEG and habitual seizures, CT and optimum MR. In a large subgroup of these patients a comprehensive neuro-psychological examination and interictal 18FDG-PET were performed. After the non-invasive phase of the presurgical evaluation, a bilateral carotid angiography and intracarotid amytal procedure was planned in 27 patients to establish hemispheric language dominance and bilateral memory function. After proper selection, 14 patients underwent invasive video-EEG monitoring with intracranial implantation of parenchymal and/or subdural electrodes to further document the area of seizure onset. From the initial group of 160 potential surgical candidates, 40 patients (20 M, 20 F) with mean age of 31 years (range: 2 months-55 years) and mean duration of uncontrolled seizures of 16 years (range: 2 months-47 years) eventually underwent a surgical procedure. 30/40 patients were on high dose antiepileptic polytherapy. Optimum MR detected structural abnormalities, confined to a limited brain area, in 39 patients. These abnormalities were of space-occupying nature in 21 cases; an atrophic lesion was suspected in 17 patients. Structural abnormalities were most frequently located in the temporal lobe (n = 26) and the frontal lobe (n = 7). Video-EEG monitoring documented complex partial seizures in 32 patients with occasional secondary generalisation in 14. In most of these patients, seizures could be subclassified as being of temporal lobe origin based on clinical and EEG criteria. Two patients had only simple partial seizures. One patient with Sturge-Weber syndrome and a strictly unilateral angioma had hemiconvulsions. A mentally retarded patient with Lennox-Gastaut syndrome had different types of seizures. After non-invasive and invasive exploration, the area of seizure onset could be determined in all patients. Standard or modified temporal lobectomy +/- hippocampectomy were the most commonly performed procedures (n = 26). In 5 patients complete lesionectomies were performed for epileptogenic structural lesions in and outside the temporal lobe. In 2 patients only partial lesionectomies were possible; in 5 patients only biopsies could be performed. Anterior 2/3 callosotomy and hemispherectomy were each performed in one patient. Postsurgical seizure control, after average follow-up of 20 months (range: 6-40 months), was excellent in 27 patients who became seizure-free. In these patients antiepileptic therapy was tapered 2 years after surgery. An additional 4 patients continue to experience non-disabling simple partial seizures only. Patients in whom only biopsies or partial lesionectomies were performed have poor seizure control. Three patients died as a result of the intrinsic malignancy of their space-occupying lesion. Two patients who are seizure free experienced a moderate postoperative hemiparesis with subtotal recovery. Overall quality of life was substantially improved both in patients who became entirely seizure free or who experienced a very significant reduction in seizure frequency. Presurgical evaluation and epilepsy surgery are a labour intensive but rewarding therapeutic alternative for patients with medically refractory epilepsy. Besides providing therapeutic efficacy, comprehensive presurgical evaluation and epilepsy surgery allow for fruitful clinical neurological research.

Clinical trial of piracetam in disorders of consciousness due to head injury.

The authors first remind some toxicological and some pharmacological properties of piracetam (Nootropil), then present the results of a test giving evidence of the presence of this drug in the cerebrospinal fluid after intravenous administration to man. In a double blind study, the activity of piracetam is tested on 31 patients suffering from coma after head injury. Only 27 patients without intracranial space occupying lesions are taken into account. Methods and results are described. Piracetam, although showing no activity on mortality, improves the level of consciousness.

[The serial CSF lactate and pyruvate levels as a guide to prognosis after severe head injury (author's transl)]. / La détermination du lactate et du pyruvate dans le LCR comme moyen de pronostic en cas de traumatismes cranio-cérébraux graves.

We have studied the lactate-level in the CSF of 40 patients with a severe head injury. After a first group of 20 patients we concluded that those levels were usefull for predicting the outcome of those patients. After receiving new informations about the normal metabolism of lactate in the CSF of man and animals, we became more suspicious. Therefore we have studied a new group of 20 patients. The levels of lactate, pyruvate, pH, pC02 and p02 were checked both in the CSF and in the blood for a longer period. An own coma-scale was used. The results are discussed.