[Nummular headache : Subcutaneous peripheral nerve field stimulation as an individual therapeutic attempt]. / Münzkopfschmerz : Subkutane periphere Nervenfeldstimulation als individueller Therapieversuch.

BACKGROUND: Subcutaneous peripheral nerve field stimulation (sPNFS) is an established procedure for the treatment of chronic localized neuropathic pain of peripheral origin. The treatment of nummular headache primarily focuses on conservative methods with limited prospects of success. The role of sPNFS in the treatment of nummular headache has not been investigated as yet. QUESTION: Is the sPNFS an option in the management of nummular headache? MATERIALS AND METHODS: In addition to a summary of established methods in the treatment of nummular headache, sPNFS as a possible form of therapy is discussed. RESULTS: A positive effect of sPNFS in terms of the treatment of nummular headache is shown. DISCUSSION: sPNFS stimulates free subcutaneous nerves and transmits a pleasant form of paraesthesia in the area of pain. If regular conservative therapy has already been exhausted, then sPNFS might be an effective new option in the treatment of nummular headache. sPNFS is a minimally invasive and low-risk procedure. However, the high treatment cost and restrictions regarding fitness to undergo MRI are points of criticism. Further studies are needed to define its potential and role in the treatment of nummular headache.

[Pain and poverty]. / Armut und Schmerz.

BACKGROUND: Poverty is an important problem in Germany. The health effects of poverty can lead to a higher risk of disease and the arising of chronic affections. On the other hand chronic illness may support the development and continuance of poverty. The context of chronic pain and poverty has not been analyzed so far. OBJECTIVES: We investigated the correlation between chronic pain and poverty. MATERIALS AND METHODS: In a prospective manner we interviewed 20 patients with pain syndromes during our consultation hour regarding their household income. Further, data from the German Federal Statistical Office were analyzed with respect to the correlation between the incidence of a chronic pain diagnosis and household income. RESULTS: At 1546 €, the average household income of the patients studied was below the poverty level. The analyzed data showed that women suffered from chronic pain more often than men did and also had a lower income. Another economic inequality was found between Eastern and Western Germany. There was a statistically significant correlation between income and the incidence of the diagnostic codes for chronic pain (R52.1, 2, 9) for men. CONCLUSION: Our investigation showed the correlation between chronic pain and poverty. A commitment and cooperation of German medical associations and federal politics is necessary to overcome this sociopolitical issue.

[Spinal cord stimulation for thalamic pain: Case report and review of the current literature]. / Hochzervikale Rückenmarkstimulation bei Thalamusschmerz : Fallbericht und Übersicht zur aktuellen Literatur.

BACKGROUND: Spinal cord stimulation (SCS) is an established procedure for treatment of chronic neuropathic pain of peripheral origin. The efficacy of SCS in case of central poststroke pain (CPSP), especially thalamic pain, has not been adequately proven. OBJECTIVES: The efficacy of SCS as an extracranial neurostimulation method for the management of central pain syndrome was investigated. MATERIALS AND METHODS: In this study, relevant pharmacological and nonpharmacological measures for central pain management were reviewed. A case of successful SCS for thalamic pain after ischemic insult is presented. Explanatory approaches of pathophysiological processes and a review of the current literature underline our results. RESULTS: In the case presented, SCS was found effective in the treatment of thalamic pain. CONCLUSION: The efficacy of SCS might be caused by segmental and supraspinal processes and collaboration of activating and inhibiting pathways. The integrity of the spinothalamic tract is mandatory. SCS is a treatment option for central pain syndrome, especially thalamic pain. Comparable studies confirm the potency of this technique. In contrast to other neuromodulation procedures spinal cord stimulation is less invasive, has a lower perioperative risk and is often less expensive. Further studies are needed to define its potential and role in the treatment of thalamic pain.

Operative treatment of subcortical metastatic tumours in the central region.

The operative treatment of subcortical metastatic tumours within the paracentral area is still under discussion. Against the background of possible new postoperative neurological deficits and of evolving new radio oncological techniques, the indication for surgery is limited only to a subgroup of patients. In this retrospective study we present the clinical results after operative treatment of metastases within the central and paracentral brain region, with an emphasis on the short-term and mid-term functional outcome. We report on 20 patients suffering from subcortical brain metastases within the primary sensorimotor area, with a median volume on MRI-scans of 8.18 cm³. Patients were admitted to our department with a progressive hemiparesis (n = 11), focal seizures (n = 6) or other unspecific symptoms (n = 3) like headache, nausea, and neuropsychological disturbances, respectively. After updated MRI- and fMRI-scanning, intensive electrophysiological testing including MEP-brain mapping and interdisciplinary tumour-board discussion of each case, those patients were evaluated for surgery. Early postoperative control was done by MRI within the first 48 h. Follow-up took place in our outpatient department, assessing clinical criteria two and 6 weeks postoperatively, followed by clinical control and MRI-scans every 3 months. In all patients, surgery was performed under general anaesthesia, cranial neuro navigation and intraoperative motor cortex stimulation. Surgery and the early postoperative course were uneventful in all cases. After a 6 months follow-up, two patients had died. The motor deficits improved in seven patients and remained unchanged in four cases. One patient suffered from a new persistent hemiparesis. A temporary paresis occurred in two cases. In five patients there was no motor deficit pre- and postoperatively. The Karnofsky Performance Status improved in ten patients 6 months after surgery. Quality of Life, measured by the FACT-Br score, improved in 12 patients and remained unchanged in one patient. With modern techniques like fMRI-guided cranial neuronavigation and intraoperative neuromonitoring including direct stimulation of the motor cortex, microsurgical resection of subcortical paracentral metastases is feasible with an acceptable risk of neurological deterioration. Even preexistent deficits can improve with positive influence on the quality of life for oncological patients, being disabled by the symptoms caused by the cerebral lesion.

[Symptomatic lumbar spinal stenosis: diagnostic evaluation and therapeutic strategies]. / Symptomatische lumbale Spinalkanalstenose : Diagnostik und Therapie.

Lumbar spinal stenosis is a common problem in daily routine practice. In the vast majority of cases stenosis is caused by degenerative changes of the lumbar spine with neurogenic claudication being the typical symptom. This is defined as sciatic pain and discomfort which deteriorates during walking and standing, leading to progressive neurological deficits. The diagnostic evaluation is based on the typical history of the patient and the clinical examination followed by magnetic resonance imaging (MRI) and flexion-extension X-ray films as the most sensitive diagnostic tool. When clinical symptoms are mild, conservative treatment might be an option but in severely disabled patients and/or in cases of relevant neurological deficits surgical decompression, in special cases combined with instrumentation should be favoured when clinical and radiological findings match. In these cases an improvement of the clinical symptoms can be achieved in up to 90% of the patients.

[Space-occupying tumor of the temporal region with facial nerve palsy, vestibular dysfunction and hearing loss]. / Raumforderung der Regio temporalis bei Fazialisparese, vestibulärem Ausfall und Hörminderung.

A 73-year-old female patient complained of right-sided facial pain, progressive loss of hearing, giddiness when changing position, a pre-auricular swelling and lack of facial expression. Clinically there was a right-sided indolent and immovable swelling approximately 7 cm in size and an incomplete ipsilateral acute peripheral facial paralysis. Magnetic resonance tomography revealed a space-occupying lesion approximately 75 mm in diameter right temporal and multilocular metastases in the pelvis, spinal column, clavicle and skull. Histology showed this to be a well to moderately differentiated adenocarcinoma with centers of positive immune response to GCDFP-24 (gross cystic disease fluid protein). The subsequent computed tomography of the thorax and mammography located the approximately 25 mm in size primary tumor in the left breast. After surgery and radiation therapy the TNM classification was a tubular adenocarcinoma of the left breast grade 2, T2N0M1 (OSS multiple osseous, BRA brain) stage IV.

[Spinal cord stimulation at the level of the conus medullaris : treatment option for therapy-resistant postoperative neuralgia of the pudendal nerve]. / "Spinal cord stimulation" in Höhe des Conus medullaris : Behandlungsoption bei therapierefraktärer postoperativer Neuralgie des N. pudendus.

Injuries of the pudendal nerve, due to a perineal tear during delivery for example, can cause significant and debilitating neurological deficits. Aconuresis and anal incontinence, as well as sensory loss of the outer genitals or even impotency in men are the well known consequences. In addition some patients suffer from a severe neuropathic pain syndrome which is resistant to conservative treatment options. Epidural spinal cord stimulation at the level of the terminal cone of the spinal cord may be a new and successful therapeutic concept in otherwise untreatable cases.

[Operative therapy of bacterial spondylodiscitis: a retrospective study]. / Operative Therapie der bakteriellen Spondylodiszitis: Eine retrospektive Untersuchung.

OBJECTIVE: Bacterial spondylodiscitis is a rare entity in spinal surgery. This study analyses the postoperative results of 53 patients, focusing on the history, the treatment, and the course of the disease. MATERIAL AND METHODS: This retrospective study is based on the patients' medical charts, including the laboratory and microbiological data. RESULTS: Twenty-nine patients suffered from different neurological deficits ranging from isolated mild hypaesthesia (n=1) to complete paraplegia (n=6). Depending on the affected area and the extension of the infection, surgery was done either as simple decompression in 16 cases or as decompression combined with a ventral or dorsoventral stabilization in 37 patients. Staphylococcus aureus was the most important triggering organism (n=23). After a median follow-up of 11.25 months, three patients had died, and 22 patients were still disabled because of persisting pain or neurological disturbances. CONCLUSION: Because of persistent neurological deficits and possible lethal complications, spondylodiscitis remains a severe problem. Management comprises targeted antibiotic therapy and surgery in selected cases.

High resolution susceptibility weighted MR-imaging of brain tumors during the application of a gaseous agent.

PURPOSE: To employ a high resolution blood oxygenation level dependent (BOLD) method called susceptibility weighted imaging (SWI) together with the breathing of carbogen to investigate the response of cerebral tumors to this breathing gas and to assess tumor anatomy at high resolution. METHODS: Five patients with cerebral tumors (four glioblastoma multiforme, one astrocytoma [WHO grade II]) were studied using a susceptibility weighted 3D gradient echo, first order velocity compensated sequence (TE = 45 ms, TR = 67 ms, alpha = 25 degrees , FOV = 256 x 192 x 64 mm(3), typical matrix = 512 x 192 x 64), on a 1.5 T MR scanner while they were breathing air and carbogen. Signal changes between the two breathing conditions were investigated. RESULTS: The glioblastomas showed strong but heterogeneous signal changes between carbogen and air breathing, with changes between + 22.4 +/- 4.9 % at the perimeter of the tumors and - 5.0 +/- 0.4 % in peritumoral areas that appeared hyperintense on T (2)-weighted images. The astrocytoma displayed a signal decrease during carbogen breathing (- 4.1 +/- 0.1 % to - 6.8 +/- 0.3 % in peritumoral areas that correspond to hyperintense regions on T (2)-weighted images, and - 3.1 +/- 0.1 % in the tumor-center). CONCLUSIONS: SWI provides high resolution images of cerebral anatomy and venous vascularization. Combined with hypercapnia it allows for regional assessment of tumor activity.

May 1999--16 year old male with an unexpected MRI finding.

Four years after resection of a supratentorial pilocytic astrocytoma this 16-year-old boy displayed widespread leptomeningeal seeding. Although the primary tumor lacked contrast enhancement, the multiple metastatic nodules were markedly contrast enhancing. Both the initial and disseminated tumor were consistent with a pilocytic astrocytoma. He was treated with vincristin and carboplatinum and the tumor was stable up to Dec. 1998. Dissemination of low-grade intracranial astrocytoma in children occurs in only 4%. It is not a sign of malignancy. The present case is similar to previously published cases. The prognosis of these patients might be quite favorable when treated with radiotherapy and/or chemotherapy.

Spheroid control of malignant glioma cell lines after fractionated irradiation: relation to the surviving fractions at 2 Gy and colony forming efficiencies in a soft agar clonogenic assay.

Spheroid control doses (SCD50) were determined for ten human glioma lines after fractionated irradiation under oxic conditions. In addition, SF2 values and colony forming efficiencies (CFE) were measured in a soft agarose clonogenic assay. A significant relationship existed between the SCD50 values and the SF2-CFE data pairs (p = 0.01) but the SCD50 values were higher than expected from the SF2 and CFE values. This comparison shows the influence of environmental factors (different in both model systems) on reproductive tumour cell death after irradiation.

Neuronavigation in surgery of intracranial and spinal tumors.

PURPOSE: To demonstrate the new possibilities and advantages of neuronavigation in the surgery of intracranial and spinal tumors, based on patient populations treated in our hospital. MATERIALS AND METHODS: An infrared navigation system with integrated microscope guidance was used for frameless intracranial neuronavigation. The biopsies of intracranial tumors were carried out using a frame-based stereotactic technique. Intracranial navigation was, in part, combined with the use of an intraoperative CT scanner and a three-dimensional ultrasound system for data acquisition, correction of brain shifts, and intraoperative quality control. The navigation was also supported by presurgical brain mapping with magnetic source imaging. Navigation in spinal surgery was exclusively performed using an infrared navigation system in combination with an intraoperative CT scanner. RESULTS: The stereotactic tumor biopsies (n = 57) were carried out with an accuracy of 91.4% as compared with the histological diagnosis. The work flow of stereotactic procedures could be increased by using the intraoperative CT scanner. Fifty-seven patients with intracranial tumors were treated with the aid of neuronavigation between July 1997 and December 1999. These patients showed an improvement from 80% to 86% on the Karnofsky index 8 weeks postoperatively. The majority of intracranial cases were primary brain tumors (n = 30) and metastases (n = 13) in functionally important areas of the brain. In four patients, a significant brain shift was observed during neuronavigation, and could be corrected by an image update using either the intraoperative CT scanner (n = 2) or the three-dimensional ultrasound system (n = 2). The presurgical brain mapping with magnetoencephalography was shown to be reliable in the sensory cortex (n = 25). Eleven patients with a thoracic or lumbar tumor were treated by open surgery or stabilization, using a combination of spinal neuronavigation and the intraoperative CT scanner. Two patients with spinal tumors underwent navigated biopsies. Neither of them showed a reduction in the clinical stage, but the Karnofsky index improved from 63% up to 72% 8 weeks postoperatively. CONCLUSION: Neuronavigation allows very precise intracranial and spinal surgery. The problem of brain shift during the navigation procedures has been solved by intraoperative image acquisition. The use of neuronavigation was shown to improve the postoperative quality of life of patients suffering from brain and spinal tumors.

Functional thrombin receptor PAR1 in primary cultures of human glioblastoma cells.

In this study we investigated primary cultures obtained from two glioblastomas surgically removed from a 64-year-old man and a 50-year-old woman, respectively. The presence of the tethered ligand thrombin receptor PAR1 (protease-activated receptor 1) in these cells was demonstrated at the level of receptor binding by using immunofluorescence studies with the monoclonal anti-PAR1 antibody Mab 31-2. Stimulation of human glioblastoma cells both with alpha-thrombin and the thrombin receptor activating peptide TRAP-6 resulted in a series of [Ca+]i spikes as shown by confocal laser fluorescence microscopy with fluo-3 as calcium sensitive fluorescence indicator. This effect was completely blocked with the thrombin receptor antagonist peptide T1. Our results demonstrate functional thrombin receptors (PAR1) in primary cultures of human glioblastomas for the first time.

Biomechanics of fixation systems to the cervical spine.

The biomechanical evaluation of a cervical spine implant must include flexural and torsional testing if it is used for stabilizing a traumatic unstable motion segment. A cadaveric model is presented that allows flexural and torsional testing of a cervical spine motion segment, measuring the tilting angle, the translation, and the torsional angle. After measuring the intact segments, in the first series, a so-called posterior instability was created and stabilized posteriorly with the hook-plate and sublaminar wiring; anteriorly with the H-plate; and with combinations of these implants. In a second series, their stabilizing effect after complete discoligamentous instability was tested. With isolated posterior instability, it was found that the flexural stability is preserved, whereas torsional stability is markedly reduced. In cases of isolated posterior instability, only hook plating alone or its combination with anterior H-plating seemed to bring about a higher torsional stability than the intact specimen. In cases of complete discoligamentous instability, only anterior H-plate and posterior hook plate procedures combined or the hook plate alone was able to guarantee both torsional and flexural stability higher than the intact spine. Exclusive posterior wiring without postoperative external immobilization in complete discoligamentous instability may result in permanent subluxation of the functional unit. Exclusive anterior H-plate fixation in complete discoligamentous instability requires additional external immobilization in the postoperative phase to prevent flexion and torsion.

Mononuclear infiltrates in human intracranial tumors as a prognostic factor. Influence of preoperative steroid treatment. I. Glioblastoma.

One hundred ninety-nine glioblastomas were investigated for the presence of mononuclear infiltrates in the light of preoperative steroid treatment and in regard to their prognostic influence. Preoperative steroid treatment does not seem to severely influence the frequency of lymphocytic infiltration in the doses routinely administered by us. The presence of infiltrates corresponds with a better prognosis for the disease, and with a mean postoperative survival time of 8.1 months as compared to 5.6 months in the group without infiltrates, irrespective of adjuvant treatment. As a prognostic factor, infiltrates may be of relevance for a statistical evaluation, but not a reliable indicator in the individual case.

Intraoperative computerized tomography for improved accuracy of spinal navigation in pedicle screw placement of the thoracic spine.

We report on our experiences with the use of intraoperative CT imaging in surgery of the thoracic spine and on our results of pedicle screw insertion using spinal navigation and implantable fiducial markers. For our operations we used the Tomoscan M-EG and the EasyGuideSpine (Philips Medical Systems). During the operation the patient was positioned on the mobile CT table. Following dorsal preparation, small titanium screws were implanted in the vertebrae so as to serve as fiducial markers. Image data were obtained by performing a spiral CT scan. Ventilation was suspended for the duration of the CT scan. Screw insertion as well as vertebral biopsies were performed using spinal navigation. Intraoperative CT scans were obtained to confirm the position of the implants and to assess the amount of bony decompression as well as the realignment. Since 1998, 112 patients with various disorders of the thoracic spine have been operated on using the described technique. 365 screws were inserted in the area of T1 to T12. There were 23 (6.3%) misplacements of pedicle screws. In 42 cases (11.5%) we observed a minimal lateral perforation (<2 mm) of the pedicle wall. No neurological, cardiovascular, or pulmonary injury occurred. Intraoperative CT imaging influenced surgical decisions as well as the final result of surgery. Despite the use of intraoperative imaging and accurate spinal navigation, pedicle screw placement in the thoracic spine remains extremely challenging.

Incorporation of intraoperative computerized tomography in a newly developed spinal navigation technique.

OBJECTIVE: We report on the first successful incorporation of intraoperative computerized tomography in spinal navigation procedures. MATERIALS AND METHODS: All operations were performed with the aid of a Tomoscan M mobile CT system (Philips Medical Systems, Eindhoven, The Netherlands). The system comprises a mobile gantry, a mobile patient examination table, and a mobile workstation. Three different navigation systems were used: the EasyGuide (Philips Medical Systems, Eindhoven, The Netherlands), the Surgical Tool Navigator (Zeiss, Oberkochen, Germany), and a prototype of an ultrasound navigation system developed by ourselves (IVS GbR, Chemnitz, Germany). All surgical operations were performed with the patient positioned on the mobile table of the CT system. Following dorsal preparation of the vertebral region, the surgeon implanted small titanium screws in the vertebrae to serve as fiducial markers. Image data acquisition and image-to-patient registration were performed after implantation of the marker screws. The pedicle screws were inserted using the navigation system, and the position of each implant was confirmed by intraoperative CT scans. RESULTS: To date, 35 patients with various spine disorders have been operated upon using the technique described, and 161 pedicle screws have been inserted. There were no misplacements of pedicle screws. In three (1. 9 %) cases we observed lateral perforation (maximum 2 mm) of the lateral pedicle wall. We achieved a registration error of 0.85 mm (RMSE) +/- 0.42 mm (SD). CONCLUSIONS: The combination of intraoperative computerized tomography and spinal navigation allows easy navigation with a high application accuracy of 0.8 mm +/- 0.4 mm (SD) at the target point (measured in experiments with a plastic spine model). The possibility of performing an intraoperative quality check on demand markedly improves the safety of these procedures.

[Prognostic factors in acute traumatic epi- and subdural hematoma]. / Prognostische Faktoren bei akuten traumatischen Epi- und Subduralhämatomen.

The results of a retrospective study on the outcome of 147 patients with acute traumatic epidural and subdural haematomas are presented. It is shown that several factors have a significant influence on the outcome of these patients (e.g. type of haematoma, injuries of other organ systems, and findings on admission. Our conclusions: 1. Epidural haematomas have a far better prognosis than subdural haematomas. 2. For both types of haematoma the initial findings and duration of coma seem to be the main predictors of outcome. 3. The patient's age does not significantly influence outcome. 4. As for subdural haematomas, concomitant brain injuries are of greater importance to the outcome than the effects of the haematoma itself.