[Anesthesiological management in endovascular stroke treatment]. / Anästhesiologisches Management bei endovaskulärer Schlaganfalltherapie.

Early recanalization of the closed cerebral arteries after acute ischemic stroke (AIS) is the only treatment to minimize long-term disability and to reduce the associated morbidity and mortality. For a long time the only proven causal treatment of AIS was intravenous thrombolysis; however, after the publication of a series of randomized prospective studies concerning endovascular mechanical thrombectomy using stent retriever systems after AIS, new guidelines were published. It was found that endovascular treatment (EVT) dramatically improves the outcome of eligible patients. The stent retriever enables high recanalization rates by clot removal from the cerebral arterial system by means of aspiration of the thrombus via the catheter and/or by entrapping it with a stent system. The management of anesthesia during the procedure is indispensable to prevent hypoxia and hemodynamic instability; however, which form of anesthesia (i.e. general anesthesia vs. conscious sedation) is advantageous for the patient during EVT is controversially discussed. In the first studies using retrospective data conscious sedation resulted in a better outcome compared to general anesthesia following EVT; however, in prospective studies this finding could not be confirmed. To obtain optimal neurological results after AIS and EVT with general anesthesia, it is of tremendous importance not to delay the EVT due to the anesthesiology procedure. Furthermore, hypotension, hypovolemia and hypocapnia should also be strictly avoided. Finally, the optimal anesthesiological approach should be guided by the current clinical state and pre-existing comorbidities of the patient.

Is there a correlation between hippocampus and amygdala volume and olfactory function in healthy subjects?

Both amygdala (AG) and hippocampus (HC) are integral parts of the olfactory system. The present study, including a large number of healthy subjects, was performed to compare HC and AG volumes, measured by manual tracing, in relation to specific olfactory functions, including odor threshold, discrimination, identification, and odor memory tasks. It also aimed to provide age-related normative data about the volume of the HC and AG. A total of 117 healthy volunteers participated (age range 19-77 years, mean age 37 years; 62 women, 55 men). Using the "Sniffin' Sticks", subjects received lateralized tests for odor threshold, and odor discrimination. In addition, an odor memory and an odor identification task were performed bilaterally. A Mini-Mental-State test excluded dementia. MR scans were performed using a 1.5 T scanner for later manual volumetric measurements. Volumetric measurements exhibited a good reproducibility. The average volume for the right HC was 3.29 cm(3) (SD 0.47), for the left HC it was 3.15 cm(3) (SD 0.47). The average right AG had a volume of 1.60 cm(3) (SD 0.31), left 1.59 cm(3) (SD 0.3). Increasing age was accompanied by a decrease of HC and AG volumes, which were much more pronounced for the right compared to the left side. Only the volume of the right HC showed a small but significant correlation with odor threshold (r(117)=0.21; p=0.02). Importantly, this correlation was not mediated by age as indicated by the significant partial correlation when controlling for age (r(114)=0.18; p=0.049). In conclusion, the present data obtained in a relatively large group of subjects demonstrates a small correlation between the volume of the HC, as an integral part of the olfactory system, and smell function. In addition, these data can be used as the basis for normative values of HC and AG volumes, separately for men, women and different age groups. This is of potential interest in diseases with acute or chronic impairment of olfactory function, in metabolic or neurodegenerative diseases or in disorders with damage of areas involved in adult neurogenesis.

Correlation between olfactory bulb volume and olfactory function in children and adolescents.

The olfactory bulb (OB) is considered to be the most important relay station in odor processing. The present study aimed to investigate the volumetric development of the human bulb and the olfactory function during childhood and youth. Furthermore, the present study aimed to investigate a possible correlation between OB volume and specific olfactory functions including odor threshold, odor discrimination and odor identification. A total of 87 subjects (46 boys, 41 girls), aged 1-17 years (mean age 8 years), participated in this study. None of them reported olfactory dysfunction or had signs of a dysfunctional sense of smell. Whenever possible, participants received a volumetric scan of the brain and lateralized olfactory tests. Volumetric measurements of the right and left OB were taken by manual segmentation of the coronal slices through the OB. Significant correlations between OB volumes and olfactory function were observed. Both, OB volumes and olfactory function increased with age, although the correlation between structure and function was not mediated by the subjects' age. In conclusion, for the first time, the present study showed a correlation between OB volume and olfactory functions in children.

Expanding the clinical and neuroradiological phenotype of 6q27 microdeletion: olfactory bulb aplasia and anosmia.

Subtelomeric deletions of chromosome 6q may result in a syndrome with brain malformations, comprising hydrocephalus and hypoplasia of the corpus callosum. Aplasia of the olfactory bulbs (OB) or anosmia has not been described in this syndrome. We describe a 3-year-old girl and a 25-year-old man with subtelomere 6q deletions. Both patients had aplastic OB and hydrocephalus. Subtelomeric 6q deletions might be underdiagnosed as anosmia can be the only symptom.

Olfactory bulb ventricles as a frequent finding in magnetic resonance imaging studies of the olfactory system.

UNLABELLED: Background. In some species an embryologic cavity inside the olfactory bulb (OB) persists and is called olfactory bulb ventricle (OBV). It is generally assumed that OBVs in humans are solitary findings representing remnants of embryologic structures that were not fully regressed, although the incidence of OBVs was never examined. Using magnetic resonance imaging (MRI), the present study aimed to study the incidence of OBVs in healthy human subjects. Material and methods. A total of 122 individuals participated. Volumes of the right and left OB were determined using MRI scans and a standardized protocol for OB analysis. For comparison, OBs of 42 cadavers were collected and sectioned. Results. The main finding of this study was the high incidence of OBV-like structures in our study group. Seventy-two out of 122 (59%) participants yielded signs for an OBV whereas three out of 42 postmortem OBs contained histologically detectable OBV. DISCUSSION: This stands in disagreement with the previous assumption of complete obliteration at the time of birth. This discrepancy may be explained by the fact that our present findings are based on modern MRI techniques with much higher resolution than 10 or 20 years ago. Another possible explanation for the discrepancy between studies based on MRI and histopathology might relate to postmortem resorption of cerebrospinal fluid from OBVs. Especially with a long postmortem interval OBVs may collapse and may no longer appear as an open cavity.

Correlation between olfactory bulb volume and olfactory function.

The olfactory bulb (OB) is considered to be the most important relay station in odor processing. Involving 125 randomly selected subjects (58 men, 67 women; age range: 19 to 79 years), the present study aimed to investigate a possible correlation between OB volume and specific olfactory functions including odor threshold, odor discrimination, and odor identification. The history of all participants was taken in great detail to exclude possible causes of smell dysfunction. All participants received an otolaryngological investigation including a volumetric scan of the brain (MRI), lateralized olfactory tests and a screen for cognitive impairment. Volumetric measurements of the right and left OB were performed by manual segmentation of the coronal slices through the OB. Significant correlations between OB volumes in relation to olfactory function were observed, independent of the subjects' age. Additionally, OB volumes decreased with age. In agreement with previous research the present study confirmed the correlation between OB volume and specific olfactory functions. Furthermore, the correlation between OB volume and olfactory function was not mediated by the subjects' age. In conclusion, the present data obtained from a relatively large group of subjects forms the basis for age-related normative values of OB volumes.

Trigeminal activation using chemical, electrical, and mechanical stimuli.

Tactile, proprioceptive, and nociceptive information, including also chemosensory functions are expressed in the trigeminal nerve sensory response. To study differences in the processing of different stimulus qualities, we performed a study based on functional magnetic resonance imaging. The first trigeminal branch (ophthalmic nerve) was activated by (a) intranasal chemical stimulation with gaseous CO2 which produces stinging and burning sensations, but is virtually odorless, (b) painful, but not nociceptive specific cutaneous electrical stimulation, and (c) cutaneous mechanical stimulation using air puffs. Eighteen healthy subjects participated (eight men, 10 women, mean age 31 years). Painful stimuli produced patterns of activation similar to what has been reported for other noxious stimuli, namely activation in the primary and secondary somatosensory cortices, anterior cingulate cortex, insular cortex, and thalamus. In addition, analyses indicated intensity-related activation in the prefrontal cortex which was specifically involved in the evaluation of stimulus intensity. Importantly, the results also indicated similarities between activation patterns after intranasal chemosensory trigeminal stimulation and patterns usually found following intranasal odorous stimulation, indicating the intimate connection between these two systems in the processing of sensory information.

Prevention and control of hypertension and diabetes in an underserved population through community outreach and disease management: a plan of action.

Hypertension and diabetes are overrepresented in the African-American population and can be particularly devastating in this population. These diseases share genetic predisposition, medical risk factors, and environmental influences as etiologic factors, and they may be interrelated, at least in part, by obesity and accompanying hyperinsulinemia. Noncompliance with treatment plans is a significant barrier to health improvement in both diseases, but increased attention to patient involvement in care is a potential solution to this long-standing problem. The Baltimore Alliance for the Prevention and Control of Hypertension and Diabetes was established in January 1998 to promote care to the underserved community of West Baltimore, Maryland, and to improve outcomes of hypertension and diabetes. Based at the University of Maryland School of Medicine, the Baltimore Alliance comprises a community health worker program, a church-based education and screening effort, managed care and pharmaceutical company (Hoechst Marion Roussel) partners, a health policy and services research group, and inpatient/outpatient clinical care sites in the health system. Mobilization, cultural relevance, and partnership are employed to ensure that the Alliance's goals of increased patient enrollment and retention in treatment programs will be achieved. Thereby, improved outcomes--clinical, humanistic, and economic--will result. Novel as well as classic approaches to patient education, compliance, and goal achievement are being pursued. Complete expert systems for hypertension and diabetes disease management are being created and will be implemented in the near future. Baseline practices and current outcomes are being identified to act as historical controls. The organization and administration of the Alliance will serve as a prototype that others may follow.

Neuroleptic malignant syndrome. Patient with unique clinical and physiologic features.

Lethargy, marked muscle weakness and rigidity, a maximal temperature of 40 degrees C, and a maximal creatine kinase value of 17,240 IU/liter developed in a 36-year-old woman following treatment with several neuroleptics. Initial treatment with dantrolene was unsuccessful. The patient's condition improved gradually over a 10-day period with no specific therapy. Muscle biopsy revealed a contracture pattern diagnostic of malignant hyperthermia susceptibility, as well as abnormal sensitivity to fluphenazine. This report may be the first description of a patient with neuroleptic malignant syndrome in whom muscle biopsy response similar to that seen in malignant hyperthermia occurred and documents that dantrolene is not uniformly successful therapy for this syndrome.

The effect of antidepressant drugs on regional cerebral glucose utilization in the rat.

The 2-deoxyglucose (2-DG) technique is a potentially powerful method for assessing the effect of centrally acting drugs on local neuronal function in the brain. Since little is established on the effect of antidepressant drugs on local functional activity throughout the brain, we have employed this technique to study the effects of desmethylimipramine (DMI), a tricyclic antidepressant, and assessing the effect of centrally acting drugs on local neuronal function in the brain. Since little is established on the effect of antidepressant drugs on local functional activity throughout the brain, we have employed this technique to study the effects of desmethylimipramine (DMI), a tricyclic antidepressant, and assessing the effect of centrally acting drugs on local neuronal function in the brain. Since little is established on the effect of antidepressant drugs on local functional activity throughout the brain, we have employed this technique to study the effects of desmethylimipramine (DMI), a tricyclic antidepressant, and phenelzine, a monoamine oxidase inhibitor used clinically as an antidepressant, on local glucose utilization. The drugs were administered either as an acute dose, or repeatedly for 7 days, or chronically for 28 days. The local metabolic rate of glucose was determined in 30 regions of rat brain. Acute DMI increased glucose utilization in 11 regions whereas, in contrast, chronic DMI decreased glucose utilization in 7 regions of rat brain. Many of the areas affected are those of the telencephalon and diencephalon that receive prominent noradrenergic innervation. This is consistent with the notion that acute DMI treatment leads to enhanced and chronic DMI treatment leads to reduced noradrenergic functioning in the CNS. In contrast to these effects with DMI, phenelzine had little effects on glucose utilization either after acute or chronic dosing.

Levels of gamma-aminobutyric acid in cerebrospinal fluid in various neurologic disorders.

Levels of gamma-aminobutyric acid (GABA) in CSF were measured by the ion exchange-fluorometric method in 136 patients who underwent evaluation for neurologic disorders. In 19 patients with no organic neurologic or mental disorders who acted as normal controls, the mean (+/-SD) GABA level in CSF was 239 +/- 76 picomoles/mL. Patients with acute hypoxic encephalopathy showed a mean GABA level in CSF higher than that of the controls, a difference that was statistically significant. In all the other disorders studied, the mean GABA level in CSF was either equal to or lower than that found in the controls. Statistically significant reductions of the GABA level in CSF were seen in patients with Huntington's disease, dementias, cerebellar cortical atrophy, multiple sclerosis, epilepsy, and Parkinson's disease.

Gamma-aminobutyric acid in peripheral tissue, with emphasis on the endocrine pancreas: presence in two species and reduction by streptozotocin.

A screen of selected periphral organs of the rat found that gamma-aminobutyric acid (GABA) is generally present outside the central nervous system, and, of those organs examined, GABA was present at the highest concentration in the pancreas (approximately 40 pmol/mg wet wt). Furthermore, this putative inhibitory neurotransmitter was found to be present at even higher levels in islets of Langerhans tissue isolated from rat pancreas (190 pmol/mg). Administration of streptozotocin, a selective beta-cell toxin, decreased pancreatic GABA levels significantly, but had no or only small effects on the GABA content of other organs. Normal teleost (catfish) Brockmann body contains about the same level of GABA as normal rat islet tissue.

[Mandibular osteosynthesis according to the Michelet technic. II. Presentation of new material. Results]. / Ostéosynthèses mandibulaires selon la technique de Michelet. II. Présentation d'un nouveau matériel. Résultats

The purpose of this communication is: - To report the conclusions of a critical study realized in collaboration with a group of engineers and concerning some presently obtainable osteosynthesis materials. - To ascertain mechanical characteristics required by screws and plates used for this type of surgery. - To relate a 4 years experience concerning 130 osteosynthesis (32 performed with a new material worked out according to biomechanical data).