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Until this day, the drainage of cerebrospinal fluid, as necessary in case of an acute increased intracranial pressure, is conducted manually by adjusting the hydrostatic height of an external drainage bag. The associated problems with the manual open-loop control strategy are an increasing pressure error over time periods involving no correction and the inherent risk of an overdrainage, which may occur, for example, after changes of the patient’s upper body inclination angle. In this paper, an automatic control strategy is suggested to alleviate these problems thereby increasing the patient’s safety and the overall quality of the therapy. The automatic controller presented in this paper is designed for our newly developed intelligent external ventricular drainage system. The proposed controller has to guarantee robustness and performance in face of uncertain patient intracranial dynamics and nonlinearities associated with the actuator. The controller is thus designed to guarantee robust performance using a mixed uncertainty modeling approach and extended by a self-scheduling approach to compensate for input nonlinearities. Controller performance is validated in nonlinear simulations, an experimental test setup, and animal experiments, involving pigs with an artificially induced hydrocephalus. [ABSTRACT FROM AUTHOR]

In humans, intracranial pressure (ICP) is not only influenced by pathology, but also by orientation in space and body movements. Therefore, it is proposed to measure ICP dynamics and body acceleration simultaneously. An algorithm for acceleration analysis was developed to monitor orientation in space and allow more accurate examination of ICP dynamics during quiet periods. [ABSTRACT FROM PUBLISHER]

In adults, atlas burst fractures (Jefferson fractures) are not uncommon. In the pediatric population, they are extremely rare, and only few cases have been reported so far. They all showed a highly consistent clinical presentation with rare neurological deficits as well as recovery with full function without any surgical intervention. We describe a case of a Jefferson fracture in a 7.5-year-old-boy after falling onto the top of his head, presenting solely with slight neck pain. The initial radiological characteristics are presented on magnetic resonance imaging (MRI) and computer tomography (CT); the bony bridging and fusion of the fracture sites are demonstrated on CT during the course of the healing. The patient was placed in a rigid cervical collar, and his physical examination results remained normal according to age. Complete fusion of both fracture sites was seen on the third follow-up 6.5 months after presentation. In this rare case of a Jefferson fracture in a child monitored by radiological imaging techniques, important aspects of conservatively treated atlas burst fractures are illustrated. It underlines their benign character and favorable outcome with full functional recovery without any surgical intervention. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Objective: Shunting of the lateral ventricle and the posterior fossa cyst is the advocated surgical therapy for children with Dandy-Walker malformation (DWM) and associated aqueductal obstruction. The high rate of complications of combined shunting stimulated the authors to search for an alternative surgical solution. Clinical Presentation/Intervention: After transtentorial endoscopic ventriculocystostomy, a cystoventricular catheter, connected to a peritoneal shunt, was placed in a neonate with DWM and associated aqueductal obstruction. Immediately prior to ventriculocystostomy, the presence of a blocked third ventricular outflow was reconfirmed by contrast medium injection. Neuronavigation was required to define the surgical path from the lateral ventricle through the tentorium and the overlying small rim of brain parenchyma into the posterior fossa cyst. The postoperative clinical course was uneventful with radiologically proven reduction of the size of the ventricular system and the cyst. Conclusion: Cystoventriculoperitoneal shunt placement after transtentorial endoscopic ventriculostomy is a surgical alternative in very young children with DWM and associated aqueductal obstruction. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Spinal cord blood flow and the induction of heme oxygenase-1 (HO-1), an indicator of oxidative stress, were studied in the spinal cords of adult wild-type and transgenic mice overexpressing the antioxidant copper, zinc superoxide dismutase (CuZn SOD) after intrathecal administration of the potent vasoactive peptide endothelin-1 (ET-1). Gelfoam, saturated with ET-1 (40, 80, or 400 μmol/L), was positioned in the intrathecal space at the midthoracic level in anesthetized animals. Blood flow was continuously monitored by laser Doppler for 10 min after the intrathecal application of ET-1. There was a significant reduction in spinal cord blood flow to approximately 40% of control values by 10 min after the intrathecal application of the peptide in both wild-type and transgenic mice. Moreover, SB209670, a nonselective endothelin receptor antagonist, blocked this reduction in flow. Each animal was euthanized 24 h after the intrathecal administration of ET-1, and the spinal cord was prepared for quantitative immunocytochemistry. HO-1 was primarily induced in astrocytes near the dorsal surface of the spinal cord in wild-type mice. This induction was attenuated in both wild-type, treated with SB209670, and untreated transgenic mice. Together, these findings suggest that ET-1 mediates oxidative stress in the spinal cord through the modulation of spinal cord blood flow. [Copyright &y& Elsevier]

Induction of heme oxygenase-1 (HO-1) in the spinal cord was studied in adult wildtype and transgenic mice overexpressing the antioxidant copper, zinc superoxide dismutase (CuZn SOD) 24 h after intrathecal infusion of heterologous lysed blood. Double immunolabeling techniques were used to determine the extent to which HO-1 was induced in astrocytes and microglia/macrophages. HO-1 was induced in both astrocytes and microglia/macrophages in the dorsal horns near the site of infusion of lysed blood in all mice. However, the number of HO-1 labeled cells was significantly less in the transgenic as compared to the wildtype animals. Together, these findings suggest that lysed blood preferentially induces HO-1 in glia and macrophages through the generation of oxidative stress. [Copyright &y& Elsevier]

Examines the vascular responses to spinal cord injury (SCI). Information on the blood supply to the spinal cord; Experimental models of SCI; Inflammation; Presence of metalloproteinases in SCI.

Various studies have identified prognostic factors for a favorable outcome of endovascular treatment in posterior circulation. We evaluated various machine learning algorithms in their ability to classify between patients with favorable (defined as 0–2 points on the modified Rankin scale [mRS]), unfavorable (mRS 3–6), poor (mRS 5–6), and nonpoor (mRS 0–4) outcomes at dismissal.We retrospectively analyzed data from 415 patients that were treated between 2018 and 2021 from the multicentric DGNR registry. Five models (random forest, support vector machine, k-nearest neighbor, neural network [NN], and generalized linear model [GLM]) were trained with clinical input variables and evaluated with a test dataset of 82 patients. The model with the highest accuracy on the training dataset was defined as the best model.A total of 132 patients showed poor and 162 patients showed favorable outcome. All baseline variables except sex were highly significantly different between patients with favorable and unfavorable outcomes. The variables NIHSS, the presence of wake-up stroke, the administration of IV-thrombolysis and mRS pretreatment were significantly different between patients with poor and nonpoor outcomes. The best-performing NN achieved a sensitivity of 0.56, a specificity of 0.86 and an area under the curve (AUC) of 0.77 on the test dataset in the classification analysis between favorable and unfavorable outcomes. The best-performing GLM achieved a sensitivity of 0.65, a specificity of 0.91 and an AUC of 0.81 in the classification analysis between poor and nonpoor outcomes.Short-term favorable and poor outcomes in patients with acute ischemic stroke of the posterior circulation can be predicted prior to thrombectomy with moderate sensitivity and high specificity with machine learning models. [ABSTRACT FROM AUTHOR]