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1.
Acta Neurochir (Wien) ; 166(1): 278, 2024 Jun 29.
Article in English | MEDLINE | ID: mdl-38949680

ABSTRACT

BACKGROUND: Transcranial Doppler (TCD) is a technique to assess blood flow velocity in the cerebral arteries. TCD is frequently used to monitor aneurysmal subarachnoid hemorrhage (aSAH) patients. This study compares TCD-criteria for vasospasm and its association with Delayed Cerebral Ischemia (DCI). An overall score based on flow velocities of various intracranial arteries was developed and evaluated. METHODS: A retrospective diagnostic accuracy study was conducted between 1998 and 2017 with 621 patients included. Mean flow velocity (MFV) of the cerebral artery was measured between 2-5 days and between 6-9 days after ictus. Cutoff values from the literature, new cutoff values, and a new composite score (Combined Severity Score) were used to predict DCI. Sensitivity, specificity, and area under the curve (AUC) were determined, and logistic regression analysis was performed. RESULTS: The Combined Severity Score showed an AUC 0.64 (95%CI 0.56-.71) at days 2-5, with sensitivity 0.53 and specificity 0.74. The Combined Severity Score had an adjusted Odds Ratio of 3.41 (95CI 1.86-6.32) for DCI. MCA-measurements yielded the highest AUC to detect DCI at day 2-5: AUC 0.65 (95%CI 0.58-0.73). Optimal cutoff MFV of 83 cm/s for MCA resulted in sensitivity 0.73 and specificity 0.50 at days 2-5. CONCLUSION: TCD-monitoring of aSAH patients may be a valuable strategy for DCI risk stratification. Lower cutoff values can be used in the early phase after the ictus (day 2-5) than are commonly used now. The Combined Severity Score incorporating all major cerebral arteries may provide a meaningful contribution to interpreting TCD measurements.


Subject(s)
Brain Ischemia , Subarachnoid Hemorrhage , Ultrasonography, Doppler, Transcranial , Humans , Subarachnoid Hemorrhage/diagnostic imaging , Subarachnoid Hemorrhage/complications , Ultrasonography, Doppler, Transcranial/methods , Female , Male , Middle Aged , Retrospective Studies , Brain Ischemia/diagnostic imaging , Brain Ischemia/etiology , Aged , Adult , Blood Flow Velocity/physiology , Predictive Value of Tests , Cerebrovascular Circulation/physiology , Vasospasm, Intracranial/diagnostic imaging , Vasospasm, Intracranial/etiology , Sensitivity and Specificity
2.
World Neurosurg ; 178: e202-e212, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37454906

ABSTRACT

OBJECTIVE: Near-infrared spectroscopy (NIRS) is a noninvasive tool to monitor cerebral regional oxygen saturation. Impairment of microvascular circulation with subsequent cerebral hypoxia during delayed cerebral ischemia (DCI) is associated with poor functional outcome after subarachnoid hemorrhage (SAH). Therefore, NIRS could be useful to predict the risk for DCI and functional outcome. However, only limited data are available on NIRS regional cerebral tissue oxygen saturation (rSO2) distribution in SAH. The aim of this study was to compare the distribution of NIRS rSO2 values in patients with nontraumatic SAH with the occurrence of DCI and functional outcome at 2 months. In addition, the predictive value of NIRS rSO2 was compared with the previously validated SAFIRE grade (derived from Size of the aneurysm, Age, FIsher grade, World Federation of Neurosurgical Societies after REsuscitation). METHODS: In this study, the rSO2 distribution of patients with and without DCI after SAH was compared. The optimal cutoff points to predict DCI and outcome were assessed, and its predictive value was compared with the SAFIRE grade. RESULTS: Of 41 patients, 12 developed DCI, and 9 had unfavorable outcome at 60 days. Prediction of DCI with NIRS had an area under the curve of 0.77 (95% confidence interval 0.62-0.92; P = 0.0028) with an optimal cutoff point of 65% (sensitivity 1.00; specificity 0.45). Prediction of favorable outcome with NIRS had an area under the curve of 0.86 (95% confidence interval 0.74-0.98; P = 0.0003) with an optimal cutoff point of 63% (sensitivity 1.00; specificity 0.63). Regression analysis showed that NIRS rSO2 score is complementary to the SAFIRE grade. CONCLUSIONS: NIRS rSO2 monitoring in patients with SAH may improve prediction of DCI and clinical outcome after SAH.

3.
Front Bioeng Biotechnol ; 10: 1031600, 2022.
Article in English | MEDLINE | ID: mdl-36507259

ABSTRACT

This study aims to validate a numerical model developed for assessing personalized circle of Willis (CoW) hemodynamics under pathological conditions. Based on 66 computed tomography angiography images, investigations were obtained from 43 acute aneurysmal subarachnoid hemorrhage (aSAH) patients from a local neurovascular center. The mean flow velocity of each artery in the CoW measured using transcranial Doppler (TCD) and simulated by the numerical model was obtained for comparison. The intraclass correlation coefficient (ICC) over all cerebral arteries for TCD and the numerical model was 0.88 (N = 561; 95% CI 0.84-0.90). In a subgroup of patients who had developed delayed cerebral ischemia (DCI), the ICC had decreased to 0.72 but remained constant with respect to changes in blood pressure, Fisher grade, and location of ruptured aneurysm. Our numerical model showed good agreement with TCD in assessing the flow velocity in the CoW of patients with aSAH. In conclusion, the proposed model can satisfactorily reproduce the cerebral hemodynamics under aSAH conditions by personalizing the numerical model with TCD measurements. Clinical trial registration: [http://www.trialregister.nl/], identifier [NL8114].

4.
Eur J Neurol ; 29(2): 620-625, 2022 02.
Article in English | MEDLINE | ID: mdl-34644440

ABSTRACT

BACKGROUND AND PURPOSE: Delayed cerebral ischaemia (DCI) is a severe complication of aneurysmal subarachnoid hemorrhage that can significantly impact clinical outcome. Cerebral vasospasm is part of the pathophysiology of DCI and therefore a computed tomography angiography (CTA) Vasospasm Score was developed and an exploration was carried out of whether this score predicts DCI and subsequent poor outcome after aneurysmal subarachnoid hemorrhage. METHODS: The CTA Vasospasm Score sums the degree of angiographic cerebral vasospasm of 17 intradural arterial segments. The score ranges from 0 to 34 with a higher score reflecting more severe vasospasm. Outcome measures were cerebral infarction due to DCI (CI-DCI), radiological and clinical DCI, and unfavorable functional outcome defined as a modified Rankin Scale >2 at 6 months. Receiver operating characteristic analyses were used to assess predictive value and to determine optimal cut-off scores. Inter-rater reliability was evaluated by Cohen's kappa coefficient. RESULTS: This study included 59 patients. CI-DCI occurred in eight patients (14%), DCI in 14 patients (24%) and unfavorable outcome in 12 patients (20%). Median CTA Vasospasm Scores were higher in patients with (CI-)DCI and poor outcome. Receiver operating characteristic analysis revealed the highest area under the curve on day 5: CI-DCI 0.89 (95% confidence interval [CI] 0.79-0.99), DCI 0.68 (95% CI 0.50-0.87) and functional outcome 0.74 (95% CI 0.57-0.91). Cohen's kappa between the two raters was moderate to substantial (0.57-0.63). CONCLUSIONS: This study demonstrates that the CTA Vasospasm Score on day 5 can reliably identify patients with a high risk of developing (CI-)DCI and unfavorable outcome.


Subject(s)
Brain Ischemia , Subarachnoid Hemorrhage , Brain Ischemia/complications , Brain Ischemia/diagnostic imaging , Cerebral Infarction/complications , Computed Tomography Angiography , Humans , Reproducibility of Results , Subarachnoid Hemorrhage/complications , Subarachnoid Hemorrhage/diagnostic imaging
5.
Crit Care Explor ; 1(1): e0001, 2019 Jan.
Article in English | MEDLINE | ID: mdl-32166226

ABSTRACT

Cerebral vasospasm in the first 2 weeks after aneurysmal subarachnoid hemorrhage is recognized as a major predictor of delayed cerebral ischemia. The routine screening for cerebral vasospasm with either transcranial Doppler or CT angiography has been advocated, although its diagnostic value has not yet been determined. Our study investigated the diagnostic accuracy of detecting vasospasm by transcranial Doppler and CT angiography for the prediction of delayed cerebral ischemia and functional outcome. Additionally, agreement between transcranial Doppler and CT angiography was determined. DESIGN: Prospective diagnostic accuracy study. SETTINGS: Neurocritical care unit and neurosurgical ward at a tertiary academic medical center. PATIENTS: Between 2013 and 2016, 59 consenting patients were included. INTERVENTION: Patients undergo both transcranial Doppler and CT angiography for detection of cerebral vasospasm on days 5 and 10 after aneurysmal subarachnoid hemorrhage. Delayed cerebral ischemia was defined as secondary neurologic deterioration, not explained otherwise. Unfavorable outcome was defined modified Rankin Scale > 2 at 6 months. MEASUREMENTS AND MAIN RESULTS: On transcranial Doppler, cerebral vasospasm was observed in 26 patients (45%). On CT angiography, vasospasm was observed in 54 patients (95%). The agreement between transcranial Doppler and CT angiography was 0.47. Delayed cerebral ischemia occurred in 16 patients (27%); unfavorable outcome in 12 patients (20%). Transcranial Doppler predicted delayed cerebral ischemia with a sensitivity of 0.44 (day 5) and 0.50 (day 10), with a specificity of 0.67 (day 5) and 0.57 (day 10). CT angiography predicted delayed cerebral ischemia with a sensitivity of 0.81 (day 5 and 10) and with a specificity of 0.070 (day 5) and 0.00 (day 10). The highest accuracy for predicting unfavorable outcome was on day 5 (0.61 for transcranial Doppler vs 0.27 for CT angiography). CONCLUSION: The diagnostic accuracy of both CT angiography and transcranial Doppler for detection of cerebral vasospasm as well as prediction of delayed cerebral ischemia and functional outcome is limited. The agreement between CT angiography and transcranial Doppler is low.

7.
Regul Toxicol Pharmacol ; 62(2): 292-301, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22051156

ABSTRACT

Quantitative assessment of behavioural patterns is frequently used in rodent toxicity studies, however only limited approaches are available for monkeys. Often qualitative behavioural scoring using functional observation batteries (FOBs) is performed, with difficulties like poor reproducibility or lack of sensitivity. In this study, we investigated whether quantitative behavioural monitoring can be applied to group-housed cynomolgus monkeys. Video-tracking EthoVision® XT system and special analysis software were used to evaluate diazepam (i.v. 1mg/kg) related behavioural changes in group-housed animals. Recordings were made predose and at the anticipated time of maximum drug exposure (T(max)). General parameters such as distance travelled and velocity did not reveal the known sedative effects of diazepam. However, inspection of the automatically generated track images indicated that diazepam-treated animals had more a meandering movement pattern suggesting that diazepam induced a loss of balance which was regained by corrective movements. Therefore, parameters revealing specific aspects of the meandering movement pattern such as velocity profiles and turn angles have been analyzed and revealed an increase in the curvature and in the number of directional changes of the movement path.


Subject(s)
Behavior, Animal/drug effects , Diazepam/toxicity , Animals , Female , Macaca fascicularis , Male , Motor Activity/drug effects
8.
Curr Pharm Des ; 17(27): 2940-7, 2011.
Article in English | MEDLINE | ID: mdl-21834764

ABSTRACT

Tuberculosis (TB) with central nervous system (CNS) manifestation is a form of TB with a high mortality and morbidity. Tuberculous meningitis (TM) is the most common form of CNS-TB. Although diagnosis of CNS-TB can be challenging, early treatment of CNS-TB is related to a better outcome. If CNS-TB is suspected, even though the clinical picture is not specific, it should be immediately treated. For the treatment of CNS-TB, knowledge of the penetration across the blood-brain barrier of the various antituberculosis agents used in TB treatment is important. These will be described here in order to serve as a guide in choosing a treatment for CNS-TB. Corticosteroids have an evidence-based value in the treatment of TM and so are recommended. As for thalidomide use in CNS-TB, sound evidence is still lacking. We will also include a description of the adverse neurotoxic effects of the various other agents including their psychiatric, ototoxic and ophthalmic adverse effects.


Subject(s)
Antitubercular Agents/therapeutic use , Blood-Brain Barrier/metabolism , Tuberculosis, Central Nervous System/drug therapy , Animals , Antitubercular Agents/adverse effects , Antitubercular Agents/pharmacokinetics , Evidence-Based Medicine , Glucocorticoids/therapeutic use , Humans , Neurotoxicity Syndromes/etiology , Tissue Distribution , Treatment Outcome , Tuberculosis, Central Nervous System/diagnosis , Tuberculosis, Central Nervous System/physiopathology , Tuberculosis, Meningeal/diagnosis , Tuberculosis, Meningeal/drug therapy , Tuberculosis, Meningeal/physiopathology
9.
Clin Biomech (Bristol, Avon) ; 22(6): 674-80, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17418922

ABSTRACT

BACKGROUND: Anterior cruciate ligament (ACL) deficiency can be a major problem for athletes and subsequent reconstruction of the ACL may be indicated if a conservative regimen has failed. After ACL reconstruction signs of abnormality in the use of the leg remain for a long time. It is expected that the landing after a single-leg hop for distance (horizontal hop) might give insight in the differences in kinematics and kinetics between uninjured legs and ACL-reconstructed legs. Before the ACL-reconstructed leg can be compared with the contralateral leg, knowledge of differences between legs of uninjured subjects is needed. METHODS: Kinematic and kinetic variables of both legs were measured with an optoelectronic system and a force plate and calculated by inverse dynamics. The dominant leg (the leg with biggest horizontal hop distance) and the contralateral leg of nine uninjured subjects were compared. FINDINGS: No significant differences were found in most of the kinematic and kinetic variables between dominant leg and contralateral leg of uninjured subjects. Only hop distance and hip extension angles differed significantly. INTERPRETATION: This study suggests that there are no important differences between dominant leg and contralateral leg in healthy subjects. As a consequence, the uninvolved leg of ACL-reconstructed patients can be used as a reference. The observed variables of this study can be used as a reference of normal values and normal differences between legs in healthy subjects.


Subject(s)
Leg/physiology , Adult , Ankle Joint/physiology , Anterior Cruciate Ligament Injuries , Biomechanical Phenomena , Female , Hip Joint , Humans , Knee Injuries/physiopathology , Knee Joint/physiology , Male , Reference Values , Rupture
10.
J Neurophysiol ; 98(1): 196-204, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17460100

ABSTRACT

Autoinhibitory serotonin 1A receptors (5-HT(1A)) in dorsal raphé nucleus (DRN) have been implicated in chronic depression and in actions of selective serotonin reuptake inhibitors (SSRI). Due to experimental limitations, it was never studied at single-cell level whether changes in 5-HT(1A) receptor functionality occur in depression and during SSRI treatment. Here we address this question in a social stress paradigm in rats that mimics anhedonia, a core symptom of depression. We used whole cell patch-clamp recordings of 5-HT- and baclophen-induced G-protein-coupled inwardly rectifying potassium (GIRK) currents as a measure of 5-HT(1A)- and GABA(B) receptor functionality. 5-HT(1A)- and GABA(B) receptor-mediated GIRK-currents were not affected in socially stressed rats, suggesting that there was no abnormal (auto)inhibition in the DRN on social stress. However, chronic fluoxetine treatment of socially stressed rats restored anticipatory behavior and reduced the responsiveness of 5-HT(1A) receptor-mediated GIRK currents. Because GABA(B) receptor-induced GIRK responses were also suppressed, fluoxetine does not appear to desensitize 5-HT(1A) receptors but rather one of the downstream components shared with GABA(B) receptors. This fluoxetine effect on GIRK currents was also present in healthy animals and was independent of the animal's "depressed" state. Thus our data show that symptoms of depression after social stress are not paralleled by changes in 5-HT(1A) receptor signaling in DRN neurons, but SSRI treatment can alleviate these behavioral symptoms while acting strongly on the 5-HT(1A) receptor signaling pathway.


Subject(s)
Fluoxetine/therapeutic use , G Protein-Coupled Inwardly-Rectifying Potassium Channels/physiology , Raphe Nuclei/drug effects , Receptor, Serotonin, 5-HT1A/physiology , Receptors, GABA-B/physiology , Selective Serotonin Reuptake Inhibitors/therapeutic use , Stress, Physiological/drug therapy , Analysis of Variance , Animals , Baclofen/pharmacology , Behavior, Animal , Dose-Response Relationship, Drug , Drug Interactions , GABA Agonists/pharmacology , In Vitro Techniques , Male , Membrane Potentials/drug effects , Membrane Potentials/physiology , Membrane Potentials/radiation effects , Neurons/drug effects , Neurons/physiology , Patch-Clamp Techniques , Raphe Nuclei/physiopathology , Rats , Rats, Wistar , Serotonin/pharmacology
11.
Contact Dermatitis ; 51(3): 131-4, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15479201

ABSTRACT

Wet work is the main cause of occupational contact dermatitis in the cleaning industry. Dermatologists and occupational physicians need to base their primary and secondary prevention for workers in the cleaning industry on the characteristics of wet work exposures. We quantified the burden of wet work in professional office cleaning activities with a continuous standardized observation by trained observers of 41 office cleaners. Duration and frequency of wet work exposure and of different cleaning activities were assessed. Wet work made up 50% of such cleaning work. Within a typical 3-hr shift, a mean frequency of 68 episodes of wet work was observed, which classifies office cleaning as wet work. Skin exposure to irritants was markedly different among cleaners who did the same cleaning activities. Reduction in skin irritation can be achieved by training the workers. Because this group of workers, who have a low level of education, has a high risk of developing irritant hand dermatitis, a special effort on training and instruction should be made. A reduction of exposure can be achieved by: using gloves more often; using gloves for a shorter period of time; using gloves while doing activities that otherwise cause the skin to be in contact with water and cleaning substances and washing hands with water only, reserving soap for when the hands are visibly dirty.


Subject(s)
Dermatitis, Occupational/etiology , Detergents/adverse effects , Hand Dermatoses/etiology , Occupational Exposure/adverse effects , Dermatitis, Irritant/etiology , Dermatitis, Occupational/prevention & control , Female , Germany , Gloves, Protective , Hand Dermatoses/prevention & control , Humans , Occupational Exposure/prevention & control , Time Factors , Workload
12.
Contact Dermatitis ; 51(3): 135-40, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15479202

ABSTRACT

Nursing has been identified as a wet-work occupation, with a high prevalence of occupational irritant contact dermatitis. Reduction of exposure to skin irritants contributes to the prevention of occupational skin disease in nurses. The role of the use of soap and water, hand alcohol and gloves in prevention programmes is discussed. 2 additional measures for reducing exposure to skin irritants are postulated: use of hand alcohol instead of soap and water in disinfection procedures when the hands are not visibly dirty; use of gloves in wet activities such as patient washing to prevent the hands from becoming wet and visibly dirty. We investigated the effectiveness of these recommendations in a model. Mean daily wet-work exposure during nursing work was modelled: regular model. We also modelled exposure to skin irritants in combination with the implementation of these recommendations: prevention model. The hands of healthy volunteers were exposed to the regular or the prevention model over 3 weeks for 5 days a week. The change in transepidermal water loss (TEWL) on the back of the hands was measured after 3 weeks of exposure to these wet-work simulations. An increase in TEWL occurred with the regular model, while mean TEWL decreased in the prevention model. Skin irritation from occlusion by gloves appeared to be more pronounced in the regular model compared to the prevention model. The results of this study justify the conclusion that in nursing work, hand alcohol is the preferred disinfectant. Although the prevention model implies increased occlusive exposure, this has no additional irritant effect, probably because of the absence of soap exposure.


Subject(s)
Disinfectants/therapeutic use , Ethanol/therapeutic use , Gloves, Protective/statistics & numerical data , Hand Disinfection , Irritants/adverse effects , Nursing Staff/standards , Adult , Dermatitis, Occupational/etiology , Dermatitis, Occupational/prevention & control , Female , Hand Dermatoses/etiology , Hand Dermatoses/prevention & control , Hand Disinfection/methods , Hospital Units/standards , Humans , Male , Models, Biological , Netherlands , Occupational Exposure/adverse effects , Reference Values , Surveys and Questionnaires , Time Factors , Water Loss, Insensible/drug effects , Workload
13.
Behav Brain Res ; 117(1-2): 137-46, 2000 Dec 20.
Article in English | MEDLINE | ID: mdl-11099767

ABSTRACT

In contrast to the well-documented acute effects on behavioural sensitivity, chronic effects that persist for weeks or even months after the cessation of the stressor received relatively little attention. This study aimed at the long-term effects of a severe stressor, i.e. social defeat followed by individual housing. Defeated and subsequently individually housed animals displayed impaired social memory, decreased social interaction and diminished anticipation for a sucrose solution for up until a period of 3 months after defeat. Remarkably, social housing counteracted the defeat-induced effects. The impaired capability to anticipate for a reward was discussed in relation to anhedonia, an important symptom of human depression. Moreover, the disturbed memory, the chronic nature of the effects, and the therapeutic effects of social housing, suggest that the defeat model may serve as a potential model for human psychopathology.


Subject(s)
Depression , Social Behavior , Social Isolation , Socialization , Analysis of Variance , Animals , Appetitive Behavior , Conditioning, Classical , Disease Models, Animal , Male , Rats , Rats, Wistar , Reinforcement, Psychology
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