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The paper reports on auto fluorescence phenomena of inter-vertebral human discs. It systematically investigates the auto fluorescence effects of ex vivo disc specimen and reports on surgical cases to demonstrate the potential value of the new method. The paper offers biologic explanations of the phenomenon and discusses the potential value of the UV auto fluorescence technique as a diagnostic tool. Intra- and postoperative observations are made by a surgical microscope with an integrated UV light source. Quantitative measurements were carried out using a photon counter and a spectrometer ex vivo. The auto fluorescence phenomenon allows the differentiation of traumatized and degenerated disc tissue intraoperatively in some cases, it allows the differentiation of bony and collagen endplate in cervical disc surgery. The source of the auto fluorescent light emission are amino acids of the collagen molecules. The proteoglycan components and the liquid components of the disc do not show relevant auto fluorescence. Emission wavelength of disc material is equivalent to color perception. It differs due to different collagen composition of the intervertebral disc components from yellow-green to blue-green and can be visualized in situ by naked eye.UV-auto fluorescence of inter-vertebral discs is a new clinical tool that has the potential to differentiate disc material from the anatomical surrounding, to distinguish between different fractions of the disc and to give information on the quality and status of the disc material. Since the technology has just emerged, it needs further investigations to quantify the clinical observations reported in this paper.

Venous aneurysms so-called isolated cerebral varix, are known as a related pathology in arteriovenous malformations (AVM) due to the arterial pressure on venous drainage16. They are also observed in combination with developmental venous anomalies (DVA)2,4,8,15. However, isolated varix is a rare entity1,7,11,13. They appear in most cases without neurological deficits. Some of the cases mimic a meningioma due to their manifestation in CT and MR imaging and their axial cortical localization. The case presented here is a isolated varix of a cortical vein located rostral to the motor strip. The patient was operated on successfully. The MRI and the histology of the case are presented.

Intraoperative neurophysiological mapping and monitoring of eloquent brain areas can be combined with image-guided localisation to enhance the safety and efficacy of surgical procedures in the motor cortex. We designed a new type of cortical electrode which can be repeatedly placed on the cortical surface and allows accurate and reproducible stimulation by means of a navigation pointer. The newly designed device consists of a monopolar electrode contact for direct cortical stimulation, housed in a holder which allows placement, easy removal, and precise repeated placement of a surgical navigation pointer. It can be used for navigation-guided, high-frequency anodal monopolar cortical stimulation (MCS) for the mapping of eloquent cortex, and for monitoring of motor pathways. While the cortex is stimulated, compound muscle action potentials (CMAP) are recorded from muscles of the contralateral extremities and are assessed both qualitatively and quantitatively. When the device is used in combination with intraoperative navigation, the stimulation sites may optionally be registered or displayed on the system monitor. This allows repeated pinpointing and obviates the need for strip or grid electrodes in the operative field; although such electrodes may be useful for continuous monitoring, they often are in the surgeon's way. In addition, the primary and supplementary motor cortex can be mapped by determining the location of the sites of stimulation on surface-projected images of the cerebral cortex.

This report describes three years of clinical experience with a new set of devices aimed at improving functional MRI of speech areas. They provide a valuable tool for pre-operative definition of hemispheric localization and spatial extension of these areas, especially in left-handed persons. The fibre-optic device described here transmits stimuli for cognitive tasks to patients undergoing MR investigations. Cognitive tasks elicit a defined brain activity lasting for several minutes. The resultant metabolic changes are detectable by functional MRI. The software (FIT ware) applied to process raw data allows semi-automated segmentation of the brain so as to obtain 3D images. Furthermore it allows the superposition of functional data. The effectiveness of the equipment was assessed on the basis of data from 140 fMRI studies. Intra-operative verification in eight patients with tumours located in the speech areas showed that the new set-up identified the speech-dominant side in each case and located speech areas in accordance with electrophysiological procedures.

Background: The 60 year old women with no prior history of arrhythmia or other cardiac symptoms was operated on for a cervical disc herniation at the level C7/D1. The C8 nerve root was visualized via a posterior approach. Findings: Removal of the sequestrum and irritation of the anterior root with surgical instruments triggered cardiac arrest. Interpretation: We offer the opinion that irritation of the anterior root led to diminished activity of the supraspinal sympathetic control system and consecutive hyper-activation of the parasympathetic system.

When there is significant loss of spinal dura mater, dural substitution with synthetic or allogenic materials is essential. In the case of laminectomy, mechanical protection and reformation of the dorsal spinal canal may be useful. This is a report on a patient with total dura loss through tumour atrophy of the dura and laminae. In order to reconstruct the dorsal face of the spinal canal a polylactide sheet was cut and shaped to fit the physiological contour. A bovine dura substitute was firmly attached and sutured to the inner surface of the polylactide shield. The implant was wedged in between the pedicles and the facet joints and resulted in a water-tight dura substitute maintaining the shape of the spinal canal and protecting it against mechanical forces and intradural scar formation.

¶ Intra-operative neurophysiological techniques allow reliable identification of the sensorimotor region and make their anatomical and functional preservation feasible. Monopolar cortical stimulation has recently been described as a new mapping technique. In the present study this method was compared to the “traditional” technique of bipolar stimulation. Functional mapping of the motor cortex was performed in 35 patients during surgery in the central region. The central sulcus (CS) was identified by somatosensory evoked potential (SEP) phase reversal. Cortical motor mapping was first performed by monopolar anodal stimulation with a train of 500 Hz (7–10 pulses) followed by bipolar stimulation (pulses at 60 Hz with max. 4 sec train duration). Surgery was performed under general anaesthesia without muscle relaxants. Of 280 motor responses elicited by bipolar cortical stimulation, 54.28% [152] were located in the primary motor cortex (PMC), 37.85% [106] outside the motor strip in the secondary motor cortex (SMC), and 8% [22] posterior to the CS. Of 175 motor responses elicited by monopolar cortical stimulation, 68.57% [120] were located in the SMC, 23.42% [41] in the SMC and 8% [14] posterior to the CS. Contrary to the general clinical view, there is considerable overlapping of primary motor units over a cortical area much broader than the “classical” narrow motor strip along the CS. Bipolar cortical stimulation is more sensitive than monopolar for mapping motor function in the premotor frontal cortex. Both methods are equally sensitive for mapping the primary motor cortex.

regimens had not yet been implemented, he was treated with a short, fully supervised, regimen of 600 mg rifampicin and 400 mg ofloxacin daily for 28 days. Clinical improvement was observed during and after the treatment. 1 year later, however, he relapsed with new lepromatous lesions, and died several months later from cardiovascular disease. M leprae (strain 92008) recovered from a skin biopsy specimen taken after the relapse was inoculated into mice footpads for standard drug-susceptibility testing. 1 Results showed resistance to dapsone, rifampicin, and ofloxacin (table). To search for gene mutations involved in rifampicin and ofloxacin resistance, DNA was extracted from the skin biopsy and, as a control, from a reference skin biopsy specimen containing an M leprae strain (90002) susceptible to the three drugs. Each extract was submitted to two different PCRs. The first amplified the rpoβ gene encoding the β subunit of RNA polymerase, restricted to the region involved in rifampicin-resistance, 4 and the second amplified the gyrA gene encoding the A subunit of DNA gyrase, restricted to the region involved in fluoroquinoloneresistance.