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K Mursch

Publications and source records attributed to K Mursch.

At least 19 recordsLinked to original sources
PubMed2006

Intra-operative diagnosis and image-guided management of an intracerebral haemorrhage occurring during ultrasound-guided biopsy.

Haemorrhagic complications occurring after burr-hole procedures are diagnosed only in symptomatic patients or when postoperative imaging is performed routinely. We report the development of an intracerebral haematoma which occurred during ultrasound-guided burr-hole biopsy. Real-time ultrasound through the same burr-hole enabled us to determine the dynamics of the bleeding and its terminal volume. The operation was finished without further complications and the patient did not experience an impairment of her neurological state. Intra-operative ultrasound is capable of detecting "invisible" complications during burr-hole procedures.

Biopsy, Needle↗
PubMed2005

Minimally invasive neurosurgery within a 0.5 tesla intraoperative magnetic resonance scanner using an off-line neuro-navigation system.

BACKGROUND AND PURPOSE: We evaluated an advanced concept for patient-based navigation during minimally invasive neurosurgical procedures. METHODS: An infrared-based, off-line neuro-navigation system (LOCALITE, Bonn, Germany) was applied during operations within a 0.5 T intraoperative MRI scanner (iMRI) (Signa SF, GE Medical Systems, Milwaukee, WI, USA) in addition to the conventional real-time system. The three-dimensional (3D) data set was acquired intraoperatively and up-dated when brain-shift was suspected. Twenty-three patients with subcortical lesions were operated upon with the aim to minimise the operative trauma. RESULTS: Small craniotomies (median diameter 30 mm, mean diameter 27 mm) could be placed exactly. In all cases, the primary goal of the operation (total resection or biopsy) was achieved in a straightforward procedure without permanent morbidity. The navigation system could be easily used without technical problems. In contrast to the real-time navigation mode of the MR system, the higher quality as well as the real-time display of the MR images reconstructed from the 3D reference data provided sufficient visual-manual coordination. CONCLUSION: The system combines the advantages of conventional neuro-navigation with the ability to adapt intraoperatively to the continuously changing anatomy. Thus, small and/or deep lesions can be operated upon in straightforward minimally invasive operations.

Adolescent↗
PubMed2005

Intrinsic brainstem tumours in adults: results of microneurosurgical treatment of 16 consecutive patients.

Intrinsic brainstem tumours in adults have a poor prognosis and surgical resection is rarely performed. Encouraged by successful operations on children performed in our department, we began a more aggressive strategy of open operations. Between 1986 and 1997, we operated upon 16 consecutive patients over 16 years of age (five female, 11 male, mean age 36.9 years) who were suffering from intrinsic tumours located in the pons and/or medulla oblongata. The extent of first open resection was 80 - 100% in two of the cases and more than 50% in nine cases. The mean survival time after the first occurrence of symptoms was 88.1 (median 34.5) months, and 39.9 (median 11) months after the first open operation. The rate of 5-year survival from the first occurrence of symptoms was 37.5% (25% after the first open surgical procedure). Thirteen out of 16 patients died within the follow-up period of at least 6.3 years, two of them within the immediate postoperative period. Eleven patients experienced a postoperative deterioration of symptoms from which only four recovered. Eight patients had from WHO grade II astrocytoma and a similar course as patients with higher-grade gliomas (n = 4). Our results indicate that open microneurosurgery for intrinsic brainstem tumours is of questionable benefit for the patient. Although surgery offers the advantages of reliable confirmation of histopathology and may be associated with prolonged survival, neurological deterioration was common and, unlike in paediatric patients, often irreversible.

Adolescent↗
PubMed2003

Internet-based interaction among brain tumour patients. Analysis of a medical mailing list.

Patients and their care providers are increasingly turning to the internet for information. Being faced with this information of very heterogeneous quality, the physician would do well to be informed about the common internet information sources. We investigated the e-mails of a mailing list (or "support group") serving about 380 brain tumour patients and their care providers. The mails were obtained from an archive and grouped according to their topic. Within 6 months, 3,272 e-mails were distributed to every group member. Alternative treatments were the most frequently discussed topics (15 %). These discussions dealt with serious new strategies as well as dubious drugs and methods. A critical attitude towards "quacks" was common, but not the rule. More than 10 % of the mails dealt with debates about therapeutic strategy and about symptoms. The individual course of the participants' illness was often reported very frankly. Emotional support between members played another great role in the support group. Criticism of physicians was rare compared to recommendations of specific therapists (3 % vs. 4 %) and included lack of empathy or sensibility and poor communication between physicians. The brain tumour mailing list is a communication medium for brain tumour patients and their care providers, which distributes and reproduces information of heterogeneous quality. The physician faced with this information should be unbiased but cautious.

Brain Neoplasms↗
PubMed2001

Differential response of mature TrkA/p75(NTR) expressing human and pig oligodendrocytes: aging, does it matter?

A differential morphological response of mature oligodendrocytes (OL) isolated from human and pig brains to the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) and to the nerve growth factor (NGF) was observed. In both cases, OL regenerate their processes; however, the rate and the extension of the process formation of human OL were behind that of pig OL. Presumably, the advanced age of the human tissue in these experiments might have contributed to this decrease in process formation, an effect that was already observed for rat OL [Yong et al. (1991) J Neurosci Res 29:87-99]. The less effectivity of NGF via TrkA, which was immunocytochemically shown in human OL, and of TPA via the protein kinase C (PKC) pathway, may have its common focus on the mitogen-activated protein kinase (MAPK) cascade. In this context, it was noted that only a few studies on aging of mature OL are available. It is conceivable that age-related changes in the properties of OL could be an important factor for their cellular responsiveness during longer lasting demyelinating diseases such as multiple sclerosis. Hence, this review would like to provide a basis for future investigations on the aging of mature OL. The data presently available suggest a preliminary classification of mature OL into three categories.

Aging↗
PubMed2001

Blood flow velocities in the basal vein after subarachnoid haemorrhage. A prospective study using transcranial duplex sonography.

BACKGROUND: Early recognition of emerging delayed neurological deficits (DND) in patients after subarachnoid haemorrhage (SAH) is not always possible by transcranial Doppler sonography. Aim of this study was to investigate a) whether determination of blood flow velocities in deep cerebral basal veins can predict DND in these patients b) the correlation of venous flow velocity to cerebral blood flow (CBF). METHODS: a) We prospectively investigated the mean flow velocity in the basal vein (VBVR), in the middle cerebral artery (VMCA) and in the extracranial internal carotid artery (VICA) in 66 patients after spontaneous SAH. Examinations were performed daily during the first 10 days, using transcranial duplex sonography. Thirty-seven patients had VMCA exceeding 120 cm/s. They were categorised in three groups: 1: no delayed neurological deficit; II: transient DND; III: permanent DND or death associated with vasospasm. b) In another group of 14 patients, interdiane variations in global cerebral blood flow (CBF) measured by the Kety-Schmidt-method were correlated with variations in VBVR, VMCA, and VICA. FINDINGS: a) In patients without deficit, VBVR was significantly elevated above normal values the first day (p < 0.05), and days 5 and 6 (p < 0.1) after VMCA exceeding 120 cm/s. In group III (permanent deficit), flow velocities in the BVR were significantly below normal on day 5 (p < 0.05) and 9 (p < 0.1). b) The correlation between changes in VBVR to changes in CBF (r = 0.78, p < 0.001) was closer than between changes in VMCA to the changes in CBF (r = 0.54, p < 0.05). INTERPRETATION: In case of elevated VMCA, patients with higher VBVR seem to have a better outcome. Changes in CBF correlate better with VBVR than with arterial flow velocities.

Adult↗
PubMed2001

Amygdala lesion in temporal lobe epilepsy subjects impairs associative learning of emotional facial expressions.

To investigate the role of unilateral amygdala lesions on processing emotions, 22 drug-resistant temporal lobe epilepsy (TLE) subjects (12 with left-sided and ten with right-sided focus) were tested, after anterior temporal lobectomy or selective amygdalo-hippocampectomy on two associative learning tasks containing emotional and neutral facial expressions, respectively. Volumetric lesion analysis was performed on the basis of 3-D MR images. No effects of lesion side were found in TLE subjects. Taken the extent of amygdala damage into account, an interaction effect could be shown between task (learning of neutral facial expressions versus emotional facial expressions) and group (subjects with little versus considerable amygdala damage), indicating worse performance of subjects with considerable amygdala damage in learning emotional facial expressions. Subjects with considerable amygdala damage were also significantly impaired in learning emotional facial expressions when compared with control subjects.

Adult↗
PubMed2001

Ultrasonography.

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Computer Systems↗
PubMed2000

Characterization of the contractile and relaxant action of the endothelin-1 precursor, big endothelin-1, in the isolated rat basilar artery.

The presence of functional endothelin converting enzyme (ECE) activity in basilar artery ring segments was investigated by measuring the contractile and relaxant effects of big endothelin (ET)-1. Under resting tension conditions cumulative application of big ET1-1 elicited a concentration-related contraction with the concentration-effect curve (CEC) shifted to the right against ET-1 by a factor of 31 and 29 in segments with the endothelium intact or mechanically removed, respectively. Preincubation with the ET(A) receptor antagonist, BQ123, induced an apparently parallel rightwards shift without affecting the maximum contraction. This shift was more pronounced for ET-1 than for big ET-1. With the putative ECE inhibitor phosphoramidon (10(-3) M) in the bath a small rightwards shift of the CEC for big ET-1 was observed in control segments and a more marked one in de-endothelialized segments. In segments precontracted with prostaglandin (PG) F(2alpha) big ET-1 induced a significant although transient relaxation whereas ET-1 did not. However, in the presence of BQ123 both ET-1 and big ET-1 elicited concentration-related relaxation with a significantly higher maximum effect obtained with big ET-1. The potency was 13 fold higher for ET-1, which is markedly less than that found for contraction. The results, therefore, suggest 1) the presence of functional ECE-activity in the rat basilar artery wall, and 2) differences in the functional ECE activity located in the endothelium and media.

Animals↗
PubMed2000

Peroperative cardiovascular stability during brainstem surgery. The use of high-dose methylprednisolone compared to dexamethasone. A retrospective analysis.

BACKGROUND: In neurosurgical procedures within brainstem structures, corticosteroids are routinely administered to prevent oedema and to reduce intraoperative trauma. After replacing the routine administration of dexamethasone (DX) by high-dose methylprednisolone (MP) during surgery for tumours within brainstem structures, a decreased incidence of intraoperative haemodynamic instability events was observed. To test this hypothesis, a retrospective analysis was performed. METHODS: Peroperative data of 62 surgical procedures of brainstem tumours were retrospectively analysed with respect to haemodynamic instability requiring changes in surgical strategy and/or emergence medication with vasoactive drugs. Severe changes in haemodynamic parameters were defined as a significant increase or decrease in heart rate and/or mean arterial blood pressure greater than 30% compared to baseline values. From 1988 to 1994, intravenous dexamethasone was given peroperatively in 33 patients. After a bolus of 1 mg kg(-1) body weight (BW) 30 min preoperatively, 0.2 mg kg(-1) were given every 4 h. From 1994 until now, methylprednisolone was administered instead of dexamethasone in 29 patients. After an initial bolus of 30 mg kg(-1) BW immediately before surgery, 5.4 mg kg(-1) h(-1) were given 23 h postoperatively. RESULTS: The results of this retrospective analysis suggest that the number of operations with episodes of bradycardia, arterial hypotension (P<0.05), tachycardia and arterial hypertension (P<0.005) was significantly decreased in the group of patients treated with high-dose methylprednisolone. CONCLUSION: The retrospective analysis of the clinical data showed that the routine use of high-dose methylprednisolone was associated with a decreased incidence of haemodynamic instability in a selected group of patients undergoing brainstem surgery. This finding has to be proven in prospective double-blind controlled studies.

Adolescent↗
PubMed2000

The influence of airway pressure changes on intracranial pressure (ICP) and the blood flow velocity in the middle cerebral artery (VMCA).

OBJECTIVE: Due to the exponential shape of the intracranial volume-pressure relation, simple measurement of epidural, parenchymal or intraventricular intracranial pressure (ICP) in traumatic brain injury (TBI) often fails to early recognize patients with a fulminant development of intracranial hypertension even during recently available methods of tissue PO2 and microdialysis measurements. One approach to this problem could be repetitive intracranial volume provocations to evaluate a trend of the intracranial elastance. Several previously published methods use invasive volume challenge through access to the cerebrospinal fluid (CSF). This pilot study describes changes in intracranial pressure due to variations of airway pressure with BIPAP ventilation maneuvers. PATIENTS AND METHODS: Ten patients with severe TBI were enrolled and completed the study. The inclusion was based on radiologic signs due to TBI in the first CT-scan and the clinical indication for insertion of an ICP monitoring device. Patients with elevated ICP above 20 mm Hg were excluded. The epidural ICP response together with haemodynamic parameters in relation to defined airway pressure changes (delta PAW) was detected. The influence of the duration of delta PAW was evaluated additionally. Data of central venous pressure (CVP), ICP, mean arterial pressure (MAP), cerebral perfusion pressure (CPP), airway pressure (PAW) and blood flow velocity of the middle cerebral artery (VMCA) were analyzed on the basis of differences between the maximum (inspiration) and minimum PAW values (expiration). RESULTS: Elevations of PAW in the range of 20 to 35 cm H2O resulted in changes of the ICPmean from 4.1 to 6.0 mm Hg (r = 0.9, p < 0.05). A correlation was estimated for the changes of systolic arterial pressure (Part) and CPPmean due to PAW variations which ranged between 4.5 and 11.6 mm Hg (r = 0.99, p < 0.05). Concerning the transcranial doppler measurements the data of changes of the blood flow velocity of the middle cerebral artery (VMCA) revealed a positive correlation to PAW with a r = 0.99, p < 0.05. CONCLUSIONS: Elevation of the venous outflow resistance and a transient increase in cardiac output have to be considered as mechanisms for transduction of transthoracic pressure changes to intracranial pressure variations. We conclude, that trends of changes in elastance can be derived from intermittent airway pressure variations. This can be useful in easy and on line dynamic monitoring of ICP in traumatic brain injury.

Air Pressure↗
PubMed2000

Effects of the sitting position on the distribution of blood volume in patients undergoing neurosurgical procedures.

The use of the sitting position in neurosurgery is often associated with decreased arterial pressure (MAP) and stroke volume index (SVI). A shift in blood from the intra- to the extrathoracic compartment may be responsible for this cardiovascular response. However, little is known of the amount of shift in blood volume after transfer from the supine to the sitting position. Therefore, we measured simultaneously changes in intrathoracic blood volume (ITBV) caused by a change in body position in anaesthetized patients. Measurements of cardiac index (CI), ITBV, pulmonary (PBV) and total circulating (TBVcirc) blood volumes were performed in the supine and sitting position. CI, ITBV, PBV and TBVcirc were measured using a thermodye dilution technique. Fluid input was restricted to 14 ml kg-1 before induction of anaesthesia. Change in body position caused a significant decrease in ITBV and was accompanied by a significant decrease in CI, SVI and MAP. Changes in ITBV correlated (r = 0.78) with changes in SVI. Thus a change in blood volume distribution between the intra- and extrathoracic compartment occurred after a change from the supine to the sitting position. Indicator dilution enables quantification of this shift and may be helpful in guiding fluid therapy in selected patients.

Adult↗
PubMed2000

Blood flow velocities in middle cerebral artery branches after subarachnoid hemorrhage.

In a prospective study, 55 patients were examined by transcranial duplex sonography (TCCS) after subarachnoid hemorrhage (SAH) to determine whether additional transcranial duplex examination on the middle cerebral artery M2 segments would aid in the examination of the MCA stem segment. The mean blood flow velocities and pulsatility index were correlated to the occurrence of delayed ischemic neurologic deficits (DIND). Out of 47 patients included, 21 did not experience any delayed deficit (group I), 15 did (group II), and in 11 the extent to which vasospasm contributed to a neurologic deficit was unclear (group III). The highest blood flow velocity and the greatest increase of mean blood flow velocity on 1 day were significantly higher in groups II and III both in M1 and in M2. In 10 patients in group II, where the onset day of DIND was known exactly, Doppler data indicating ischemia before or at the time of DIND were observed in nine. In eight patients, Doppler of the MCA stem alone would have provided enough information to recognize the risk of symptomatic vasospasm; in one patient, only the M2 Doppler gave an indication of ischemic complication. Transcranial duplex sonography may provide additional information to TCD by accurate delineation of M1/M2 vasospasm and therefore may help plan cerebral angiography and neurointerventional treatment.

Adult↗
PubMed1999

Venous intracranial haemodynamics in children undergoing operative treatment for the repair of craniosynostosis. A prospective study using transcranial colour-coded duplex sonography.

To evaluate intracranial venous haemodynamics in craniosynostosis noninvasively, we measured the blood flow velocities and pulsatility indices in the superior sagittal sinus (SSS) and the middle and the anterior cerebral artery during the perioperative course in 21 children undergoing repair of craniosynostosis involving the midline sutures, using transcranial colour-coded duplex sonography (TCCS). An age-matched group of 12 healthy children was examined in like manner for comparison. In the healthy group, the mean pulsatility index (PI) in the SSS was 0.22 and the mean resistance index (RI) 0.20. The mean preoperative PI and RI in the synostosis group were significantly higher [0.41 and 0.34, respectively (P<0.01)], but fell to 0.19 and 0.17 (P<0.01) in the postoperative course. Our results indicate that in craniosynostosis there is an altered venous haemodynamics in the SSS, which can be observed noninvasively by TCCS.

Blood Flow Velocity↗
PubMed1999

Elevated cerebral perfusion pressure and low colloid osmotic pressure as a risk factor for subdural space-occupying hygromas?

BACKGROUND: Space-occupying subdural hygromas are a late complication of severe traumatic brain injury (TBI) and may delay the patient's recovery. To evaluate the risk factors involved, we performed a semiretrospective, -prospective analysis of three groups of patients, which differed with regard to the techniques used in the management of their cerebral perfusion pressure (CPP) and colloid osmotic pressure (COP) to determine the occurrence of space-occupying subdural hygromas. PATIENTS AND METHODS: Between 1989 and 1997 we examined 696 patients after a severe TBI: Group 1. 1989-1994 mean CPP: 67 (elevated for therapeutic reasons by catecholamines, if necessary), mean COP: 19. Group 2. January 1995-October 1996, mean CPP: 77, mean COP: 20. Group 3. November 1996-December 1997, mean CPP: 79, mean COP: 23 (elevated for therapeutic reasons by infusions of colloids). The groups were comparable for other criteria. RESULTS: Compared to Group 1, Group 2, with a high CPP but lower COP, showed a significantly higher (p < 0.01; chi2-test with correction of Yates) percentage of posttraumatic subdural hygromas with space-occupying aspects, clinical signs of bradycardia, hypertension and impaired consciousness requiring surgery (Group 1: 1.75%; Group 2: 10.46%; Group 3: 0%). In Group 3 we saw no patient with a space-occupying hygroma. CONCLUSION: We conclude that iatrogenic elevated CPP, which has been reported to be helpful in preventing secondary ischemic damage after a severe TBI, may be harmful to a patient if the COP is not maintained within physiological ranges.

Adult↗
PubMed1999

Cisternal S100 protein and neuron-specific enolase are elevated and site-specific markers in intractable temporal lobe epilepsy.

In the brain, S100 protein and neuron-specific enolase (NSE) are mainly found in glial cells and neurons, respectively. We investigated concentrations of S100 protein and NSE in cisternal cerebrospinal fluid obtained during implantation of foramen ovale electrodes in eight patients with temporal lobe epilepsy (TLE). In addition, the meningeal markers cystatin-C and beta-trace as well as total protein were measured. Patients with trigeminal neuralgia (TN) undergoing glycerol rhizotomy served as controls. S100 protein and NSE levels ipsilateral to the site of seizure onset were significantly higher than in TN. Contralateral TLE values were also markedly but not significantly elevated. The meningeal markers cystatin-C and beta-trace protein as well as total protein did not differ in TLE and TN. We conclude that interictal temporal lobe dysfunction corresponds with neuronal and glial marker elevations in the extracellular space and that site-specific elevations may predict the site of seizure origin biochemically.

Adult↗