Monitoring motor function during resection of tumours in the lower brain stem and fourth ventricle

Objectives Even in the days of modern microsurgery, the removal of a brain stem lesion remains a surgical challenge. Especially when operating on children, the prognosis is directly related to the radicality of the resection; however, a radical resection is often associated with surgical morbidity. Intraoperative neuromonitoring could help to minimise the surgical morbidity, but few studies have been performed to clarify the value of this monitoring. We investigated a prospective series of 21 patients with lesions involving the brain stem for the prognostic value and benefits of neuromonitoring.Methods We performed intraoperative neuromonitoring of cranial nerve function by electromyography (EMG) and motor evoked potential (MEP). The results were correlated with postoperative neurological deficits.Conclusions There is a good correlation between intraoperative neurophysiological events and postoperative neurological deficits in patients with lesions of the brain stem. In general, transient, prolonged, spontaneous activity in EMG is associated with a transient paresis of the respective muscle, whereas a permanent spontaneous activity is associated with a permanent deficit. Intraoperative neuromonitoring reliably predicts postoperative neurological function in patients with tumours of the lower brain stem and fourth ventricle. This neuromonitoring guides the neurosurgeon in the operation and may decrease surgical morbidity. We recommend using monitoring of MEP and EMG of the lower cranial nerves in surgery on all patients with lesions involving the lower brain stem and fourth ventricle.     

Current determinants of 30-day and 3-month mortality in over 2000 aortic valve replacements: Impact of routine laboratory parameters.

OBJECTIVE: Haematological and biochemical measurements are performed routinely before surgery to exclude organ malfunction and blood cell and coagulation abnormalities. We aimed to test routinely obtained laboratory data as factors predicting operative risk. METHODS: Between 1996 and 2003, 2198 patients underwent aortic valve replacement (AVR) (908 of them with concomitant CABG) in our institute. The mean age of the study population was 69+/-11 years (range 13-91, 43% female). Clinical and laboratory parameters based on the consolidated data mart set were evaluated by multiple logistic regression analysis. RESULTS: The overall operative mortality (within 30 days) was 3.8% and the mortality after 3 months was 5.9%. In addition to clinical characteristics, the following laboratory values were identified as independent predictors of 30-day mortality: fasting blood glucose, antithrombine III, partial thromboplastine time and creatinine kinase. As independent predictors of 3-month mortality, the following laboratory values were indentified: fasting blood glucose, serum creatinine, antithrombine III, partial thromboplastine time, lactate dehydrogenase, sodium concentration and serum proteins. The discriminative power of the models increased if laboratory parameters were included in addition to preoperative clinical characteristics (from 0.75 to 0.79 and from 0.75 to 0.78 for 30-day and 3-month mortality, respectively). The discriminative power using the logistic EuroScore was lower (0.71 and 0.7, for 30-day and 3-month mortality, respectively). CONCLUSIONS: Laboratory parameters as objective markers for organ function and nutritional status are useful data for the prediction of 30-day and 3-month mortality after aortic valve replacement. Using modern methods of information technology, these valuable data which are stored electronically in most hospitals, can be used efficiently for research and quality control.     

Differential modification of muscarinic cholinergic receptors in the hippocampus of patients with Alzheimer''s disease: an autoradiographic study

We have used quantitative light microscopic autoradiographic techniques to analyze changes in muscarinic cholinergic receptors in the hippocampus in Alzheimer type dementia (ATD). The density and distribution of muscarinic cholinergic receptors has been correlated with the density of neurons, neuritic plaques and neurofibrillary tangles in the CA1 subfield of the hippocampus of control and ATD patients. The number of pyramidal cells per mm² in the CA1 sector was significantly decreased in ATD cases as compared to controls, although there were large variations among cases. The most marked reductions in cell counts were observed in patients with a history of profound dementia. The densities of muscarinic receptors, as well as the proportions of M₁ and M₂ subtypes, in the CA1 sector and dentate gyrus were not significantly different between ATD and old non-demented patients. Neuritic plaques, even in high numbers, did not affect the density of muscarinic receptors; moreover, the densities of receptors over the neuritic plaques did not differ from the surrounding neuropil. However, in some ATD cases there was a marked decrease in the concentration of these receptors in the CA1 sector and subiculum, with no change in the proportions of muscarinic receptor subtypes. These patients exhibited frequent extracellular remnants of neurofibrillary tangles (ghost tangles), but scarce neuritic plaques, and were those showing severe losses of pyramidal cells. There was a significant positive correlation between the total concentration of muscarinic receptors in the CA1 and the density of pyramidal cells, suggesting that decreases in receptor concentration result from a severe neuronal loss. We observed that the ratio of muscarinic receptors per pyramidal cell was significantly increased in ATD patients. This might indicate a possible upregulatory mechanism for muscarinic receptors in the population of remaining neurons in ATD. However, decreases of receptor numbers following severe neuronal fall out suggest that compensatory mechanisms are no longer possible in such cases. The question is raised whether these differences between cases reflect different diseases or different stages of the same disease.     

Chemical aspects of self-etching enamel-dentin adhesives: a systematic review.

OBJECTIVES: The paper gives an overview on the components and the polymer chemical aspects of currently used self-etching enamel-dentin primers/adhesives. In addition, the contribution of new adhesives monomers and cross-linkers exhibiting enhanced hydrolytic stability than methacrylates to improve the performance of single-bottle adhesives is discussed. SOURCES: Information from original scientific papers or reviews about enamel-dentin adhesives, the patent literature concerning dental adhesives and manufacturer information of commercial self-etching adhesives were included in this review. DATA: The most efficient self-etching enamel-dentin adhesives are based on strongly acidic adhesive monomers, containing dihydrogenphosphate, phosphonic acids or carboxylic acid groups. Serious problems of single-bottle water-based, strongly acidic self-etching enamel-dentin adhesives arise both from the hydrolytic instability of the methacrylate monomers used and the side reaction of the applied initiator components. CONCLUSIONS: The stability of the self-etching enamel-dentin adhesives can be improved by using new acrylic ether phosphonic acids or mono- or difunctional acrylamides, while more stable and compatible components have to be developed in the future.     

Rotatory palmar subluxation of the lunate in post-traumatic ulnar carpal translocation

Post-traumatic ulnar carpal translocation is a rare, severe ligamentous injury to the wrist. Radiologic findings include widening of the radiocarpal joint space at the radial styloid process and ulnar displacement of the carpus. Less than 50% of the lunate articulates with the radius in the neutral position; the lunate is tilted dorsally with palmar subluxation due to a ruptured radioscapholunate (RSL) ligament. This malposition should be called rotatory palmar subluxation of the lunate (RPSL), by analogy to rotatory subluxation of the scaphoid (RSS). In contrast to dorsiflexed intercalated segment instability (DISI), in RPSL the RSL ligament is ruptured and, in the majority of cases, the scapholunate ligament remains intact. A prompt diagnosis should lead to successful treatment.     

Development of a short version of the Apathy Evaluation Scale specifically adapted for demented nursing home residents.

OBJECTIVE: Apathy is among the most frequent neuropsychiatric symptoms in dementia, particularly Alzheimer disease. The Apathy Evaluation Scale (AES) has been widely employed for assessing apathy in different patient groups. To further facilitate the usage of the AES, an abbreviated version was constructed. METHOD: On basis of a sample of 356 nursing home residents, a cross-validation procedure was carried out to develop a brief version of the AES. According to a thorough clinical examination, 85% of the residents were demented, 8% presented with mild cognitive impairment, whereas 7% did not present any cognitive deficits. After subdividing the patient group into two matched samples, the first subsample was used to identify problematic items due to defined psychometric and content-related criteria. The original 18-item scale was thus reduced to 10 items. Psychometric properties of the shortened version were subsequently reassessed in the second subsample. RESULTS: The short version demonstrated favorable psychometric properties that could be confirmed by cross-validation with the second sample. Correlations with the original full-length version were high (r = 0.97 for both subsamples); the shortened scale yielded no substantial losses regarding internal consistency or construct validity (correlations with the respective subscales of the Neuropsychiatric Inventory). CONCLUSION: The frequency of apathetic symptoms in the nursing home residents included confirms the clinical importance of apathy for understanding dementia. Given this specific patient population, setting, and mode of data collection, the short-version AES seems to be a valuable and time-efficient instrument for assessing apathy.     

Epilepsie im Kindesalter: Wann kann die antiepileptische Therapie abgesetzt werden?

Zusammenfassung Der richtige Zeitpunkt für das Absetzen der Antiepileptika (AE) im Kindesalter ist unbekannt. Anl?sslich ihrer Jahrestagung haben die Mitglieder des K?nigsteiner Arbeitskreises (KA) eigene und publizierte Absetzstrategien diskutiert. Da Studien zu diesem Thema rar und widersprüchlich sind, wurde beschlossen, die Diskussionsergebnisse im Sinne einer Meinungs?u?erung zu publizieren. Bei Neugeborenen besteht übereinstimmung, AE innerhalb von 2 bis 12 Wochen nach dem letzten Anfall abzusetzen. Bei BNS-Epilepsie wird Vigabatrin nach 6 bis 12 und Sultiam nach 6 bis 36 Monaten abgesetzt. Nach erfolgreicher Steroidtherapie setzt die Mehrheit des KA die AE-Therapie für zwei Jahre fort. Für die Rolando-Epilepsie sind 1 bis 3 Jahre Anfallsfreiheit ausreichend, auch wenn fokale Spike-Waves persistieren. Im Falle einer symptomatisch fokalen Epilepsie ist die Grunderkrankung mitentscheidend für das Absetzen. Die Behandlung der Absencen-Epilepsie kann nach zwei Jahren beendet werden, w?hrend bei myoklonisch- astatischer Epilepsie meist eine 2- bis 5-j?hrige Anfallsfreiheit vorausgesetzt wird. Konsens besteht darüber, dass die Juvenile- Myoklonus-Epilepsie ein sehr hohes Rückfallrisiko birgt. Dennoch ziehen einzelne neurop?diatrische Mitglieder einen Absetzversuch nach 2- bis 3-j?hriger Anfallsfreiheit in Betracht. Die überwiegende Mehrheit des KA führt aber bei gesicherter Diagnose keinen Absetzversuch durch. Bezüglich der Absetzgeschwindigkeit wird ein langsames (3 bis 12 Monate) Ausschleichen favorisiert. Nur zwei Mitglieder praktizieren ein rascheres Absetzen (<3 Monaten). Das EEG spielt für die Entscheidung eine untergeordnete Rolle und bleibt auf bestimmte Epilepsieformen (z. B. Absencen-Epilepsie) beschr?nkt. Das vorliegende Papier gibt die Meinung des KA wieder und eignet sich nicht im Sinne einer Leitlinie. Für die Entscheidung AE abzusetzen, ist immer eine individuelle Abw?gung von Grunderkrankung, Epilepsieform und psychosozialen Umst?nde erforderlich.      

Current practice patterns in pancreatic surgery: Results of a multi-institutional analysis of seven large surgical departments in germany with 1454 pancreatic head resections, 1999 to 2004 (german advanced surgical treatment study group)

Despite decreasing mortality rates, morbidity is still high after pancreatic head resection. Comparative data in the United States and Europe show a relationship between hospital volume and mortality. Treatment strategies vary frequently, partially because of the lack of evidence-based data. We performed a multi-institutional analysis in Germany evaluating current numbers, indications, techniques, and complication rates of pancreatic head resection. Questionnaires were completed by seven high-volume surgical departments regarding quantitative and qualitative aspects of pancreatic head resections in the period from 1999 to 2004 (five prospective and two retrospective institutional databases). A total of 1454 pancreatic head resections (944 for malignancy) were reported. Mean annual hospital volume ranged from 14 to 52 (10 to 43 in malignancy). Mortality was between 1.1% and 4.8%, morbidity was between 24% and 46%, and pancreatic leakage was between 9% and 20%. In malignant disease, all centers perform standard lymphadenectomy and regard arterial infiltration as a contraindication for resection. However, the rate of portal vein resection varied from 0% to 28%. No consensus is seen on the type of surgery for malignancy and chronic pancreatitis. After resection for pancreatic cancer less than one fourth of the patients receive adjuvant therapy. The results of our analysis in Germany confirm that pancreatic head resection can be performed with low mortality in specialized units. Variations in indications, operative technique, and perioperative care may demonstrate the lack of evidence-based data and/or personal and institutional experience. The low number of patients receiving adjuvant therapy after resection of pancreatic cancer suggests that more efforts must be made to establish novel adjuvant therapies under randomized study conditions. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation).