[Interdisciplinary neurovascular networks: state of the art]. / Interdisziplinäre neurovaskuläre Netzwerke: eine Standortbestimmung.

BACKGROUND: In order to treat the complete spectrum of neurovascular diseases at a high level of quality, which goes beyond the purely acute treatment of stroke, the German Stroke Society (DSG) together with the German Societies for Neurosurgery and Neuroradiology developed a certification procedure for neurovascular networks (NVN). Structurally, a NVN consists of a coordinating center with at least three neurovascular network partners with a certified stroke unit. From 2018 to 2020 a total of 15 NVN have so far been audited and certified according to this new standard. OBJECTIVE: How efficient are the NVN? Are high standards maintained? MATERIAL AND METHODS: The reports of the audits were analyzed. The data were taken from the period 2017-2019. RESULTS: The 15 NVN treated a total of 86,510 stroke patients in the years examined and were networked with a total of 107 partner clinics, which were situated an average of 25 km from the coordinating center and transferred a total of 2726 patients. The coordinating centers performed 2463 thrombectomies and treated 2383 patients with nontraumatic intracerebral bleeding. In 712 patients with acute aneurysmatic subarachnoid hemorrhages endovascular treatment was carried out and clipping in 401. The audit was successful in the majority of the NVN. CONCLUSION: The certification process of NVN has been successfully established and the audits proved to be a useful instrument for quality control and improvement. The 15 NVN are highly efficient and treat more than one quarter of stroke patients in German stroke units.

Factors associated with non-participation and dropout among cancer patients in a cluster-randomised controlled trial.

We investigated the impact of demographic and disease related factors on non-participation and dropout in a cluster-randomised behavioural trial in cancer patients with measurements taken between hospitalisation and 6 months thereafter. The percentages of non-participation and dropout were documented at each time point. Factors considered to be potentially related with non-participation and dropout were as follows: age, sex, marital status, education, income, employment status, tumour site and stage of disease. Of 1,338 eligible patients, 24% declined participation at baseline. Non-participation was higher in older patients (Odds Ratio [OR] 2.1, CI: 0.6-0.9) and those with advanced disease (OR 2.0, CI: 0.1-1.3). Dropout by 6 months was 25%. Dropout was more frequent with increased age (OR 2.8, CI: 0.8-1.2), advanced disease (OR 3.0, CI: 1.0-1.2), being married (OR 2.4, CI 0.7-1.1) and less frequent with university education (OR 0.4, CI -1.3 to -0.8) and middle income (OR 0.4, CI -0.9 to -0.7). When planning clinical trials, it is important to be aware of patient groups at high risk of non-participation or dropout, for example older patients or those with advanced disease. Trial designs should consider their special needs to increase their rate of participation.

Late-onset hydrocephalus in a child with Joubert syndrome: a case report.

INTRODUCTION: The ciliopathy "Joubert syndrome" was first described in 1969 by Dr. Marie Joubert and most subtypes follow an autosomal recessive inheritance. The complex disorder shows typical clinical features, such as hyperventilation, abnormal eye movements, and retardation. A pathognomonic midbrain-hindbrain malformation, the molar tooth sign, can be found on magnetic resonance imaging of the brainstem. There are a little more than 200 reports of Joubert syndrome in the literature. CASE PRESENTATION: We report a case of a 9-year-old boy who developed a progressive hydrocephalus starting from the age of 4. He underwent VP shunt placement at 8 years, which relieved hydrocephalus-related clinical symptoms and put development of the macrocephalus to a halt. CONCLUSION: Neonatal hydrocephalus due to the altered anatomy of the posterior fossa has been reported earlier, but to our knowledge, this is the first case of a delayed onset of hydrocephalus in a patient with Joubert syndrome.

Adult long-term outcome of patients after congenital hydrocephalus shunt therapy.

INTRODUCTION: Even though shunt surgery has been an established and widely accepted treatment for congenital hydrocephalus for five decades, long-term follow-up and functional outcome data is rare. PATIENTS AND METHODS: Sixty-nine patients were examined after congenital hydrocephalus had been treated between 1971 and 1987 at the Department of Pediatric Surgery (University of Leipzig) within the first 12 months of life. Median age of patients was 32 years (range 25-42 years). Patients agreed to undergo a contemporary hydrocephalus assessment. RESULTS: Seven patients (10.1%) became shunt-independent before adulthood. By the age of 20, 82% of the patients had needed at least one shunt revision, 100% by the age of 30. 21.7% of the primary valves (Spitz-Holter) remained intact without revision until today up to 35 years (mean functional intactness 23 years). Shunt infections occurred in 4.3% of primary implantations. 48% of the patients had a good functional outcome (mRS = 0-1). 40.9% of the patients attended regular school. In summary, 75% patients work on a daily basis. 44.6% live an independent life, 35.4% rely on parental supervision, and 20% depend on professional care institutions. CONCLUSION: Compared to the pre-shunt era, surgery within the first year of life is advantageous regarding visual function, educational progress, and social results. The outcome achieved throughout childhood remains stable during adult life as long as catastrophic events of shunt malfunction can be prevented. Epilepsy, motor deficits, acute shunt dysfunction, and problems of social integration as well as aging parental caregivers seem to be prominent factors of morbidity in adulthood.

[Deep brain stimulation using simultaneous stereotactic electrode placement: an alternative to conventional functional stereotaxy?]. / Tiefe Hirnstimulation mittels simultaner stereotaktischer Elektrodenplatzierung : Eine Alternative zur konventionellen funktionellen Stereotaxie?

BACKGROUND: Deep brain stimulation (DBS) has become a reliable method in the treatment of movement disorders, e.g. idiopathic Parkinson's disease (IPD) and is technically based on stereotaxy. The Starfix® platform is a new type of stereotactic frame that allows an individualized and patient-optimized therapeutic regimen in IPD. OBJECTIVES: The aim of this study was to retrospectively compare the outcomes of IPD patients who underwent surgery with the use of conventional stereotactic frames (31 patients) to those who underwent implantation of DBS with the use of Starfix® frames (29 patients). MATERIAL AND METHODS: Surgery time, the unified Parkinson's disease rating scale III (UPDRS/III) score, L-dopa and L-dopa equivalent doses (LED) were compared prior to surgery as well as 4 weeks, 12 weeks, 6 months and 1 year postoperatively. RESULTS: The IPD-related symptoms improved significantly in both groups with respect to the UPDRS III score (conventional 69.6% vs. 72.4% Starfix®). After surgery significant reductions of L-dopa and LED were seen in both groups. Inherent advantages of the Starfix® platform included simultaneous positioning of the stimulating electrodes and a significant reduction in surgical time. CONCLUSION: In summary, both stereotactic procedures are reliable and safe procedures for the placement of stimulating electrodes as well as the stimulation effect achieved. The logistical uncoupling of presurgical planning from surgical therapy emphasizes the benefits of the individualized stereotactic procedure.

Updated physiology and pathophysiology of CSF circulation--the pulsatile vector theory.

INTRODUCTION: Hydrocephalus is still a not well-understood diagnostic and a therapeutic dilemma because of the lack of sufficient and comprehensive model of cerebrospinal fluid circulation and pathological alterations. CONCLUSIONS: Based on current studies, reviews, and knowledge of cerebrospinal fluid dynamics, brain water dynamics, intracranial pressure, and cerebral perfusion physiology, a new concept is deducted that can describe normal and pathological changes of cerebrospinal fluid circulation and pathophysiology of idiopathic intracranial hypertension.

Acute two-compartment low pressure hydrocephalus--a case report.

A case of an 8-year-old-boy with shunt-dependent occlusive hydrocephalus after resection of a cerebellar medulloblastoma is presented, who experienced repeated episodes of severe neurologic deterioration with signs and symptoms of raised intracranial pressure after spinal tapping. However, intracranial pressure was recorded within low ranges, only up to the opening pressure of the implanted adjustable shunt valve. Multiple shunt revisions were performed, until the condition was recognized as acute normal pressure hydrocephalus. Either enforced recumbency and downadjustment of the valve system to 0 cm H(2)O alone or external ventricular drainage seems to be successful to resolve the critical condition, depending on severity of the symptoms. The case illustrates that acute pathologic enlargement of the ventricular system is not always associated with increased intracranial pressure, even when typical signs and symptoms are present. The very rare entity of acute normal pressure hydrocephalus by two separated compartments is postulated based on the pulsatile vector force theory of brain water circulation.

The use of 5-aminolevulinic acid fluorescence guidance in resection of pediatric brain tumors.

INTRODUCTION: Whereas in the adult population 5-Aminolevulinic acid (5-ALA) fluorescence guidance has been widely accepted for improving the extent of tumor resection, the application in children remains an off-label use. Even though most pediatric study protocols require a complete resection for improving outcome parameters, only few pediatric patients have been operated with fluorescence guidance, and it remains questionable, whether and which pediatric tumors show useful fluorescence. We present casuistic reports of application of 5-ALA in children collected from three different neurosurgical departments. PATIENTS AND METHODS: In children with suspected malignant intracerebral tumor or recurrence, individual informed consent was obtained in each case from the parents. 5-ALA was administered according to the adult protocol, with 20 mg/kg, 2 h before induction of anesthesia. We retrospectively analyzed 18 patients (13 male, 5 female; age 3-18 years), using the intraoperative neurosurgical protocol, the postoperative MRI results, and the follow-up clinical examinations. RESULTS: The use of 5-ALA fluorescence guidance proved to be safe in our group of pediatric patients. Fluorescence guidance was most useful for recurrent glioblastoma resection. Medulloblastoma tissue displayed fluorescence only inconsistently, and most pilocytic astrocytoma remained without staining. Ganglioglioma showed partial staining in the central tumor areas, without allowing the use for circumferent resection. CONCLUSION: The off-label use of 5-ALA fluorescence guidance in pediatric patients appears to be most useful in recurrent high-grade gliomas. Fluorescence accumulation in other pediatric brain tumor entities is not predictable and should be evaluated in future clinical studies before being integrated into the current treatment protocols.

Effectiveness of bevacizumab for radiation-induced cerebral necrosis in children.

INTRODUCTION: Bevacizumab has been reported to effectively reduce cerebral edema caused by radiation therapy. However, only limited data with a short follow-up in tumor patients are available so far. PATIENTS AND METHODS: Two children suffering from hemorrhage from arteriovenous malformation (AVM) have been treated with stereotactic radiotherapy and developed radiation-induced cerebral edema with deteriorating neurological status despite maximized steroid therapy. Bevacizumab administration at 5 mg/kg body weight was initiated every 2 weeks. RESULTS: Bevacizumab treatment rapidly ameliorated the neurological deficits, malignant edema and prevented catastrophic complications. Corticoid therapy could be reduced and discontinued. However, after 18 months, both patients showed identical or worse neurological status than before bevacizumab therapy. AVM radiation therapy had been successful to completely obliterate AVMs. DISCUSSION: In our limited experience, bevacizumab may be an effective and safe option for rescue therapy for malignant cerebral edema on the basis of radiation-induced necrosis especially in patients who experience rapid deterioration despite corticoid therapy and/or intolerable steroid side effects. Despite the fact that functional improvement could not be achieved in long-term outcome patients significantly stabilized and improved during periods of acute deterioration. In order to determine the long-term effectiveness of bevacizumab further investigation in placebo-controlled studies with a higher number of patients are required.

[The 'Surgical Deck': a new generation of integrated operational rooms for ENT]. / Das "Surgical Deck": Eine neue OP-Generation für die HNO-Chirurgie.

BACKGROUND: Existing operating room concepts do not meet modern technological opportunities anymore. The "Surgical Deck" is supposed to represent a prototype for a new operating room generation. The objective of the project is to achieve a better integration of functions and to develop an innovative concept for a highly developed surgical workstation. MATERIAL AND METHODS: 3 working areas are defined: Surgical, Airway and Technical Cockpit. The evaluation was conducted on 284 surgeries carried out from 01.08. 2011 to 31.01. 2012. The evaluation team consisted of 6 surgeons, 3 surgery nurses, 3 anesthesiologists and 4 anesthesia nurses. Within a detailed analysis, the data of 50 FESS surgeries were compared to those of a control group. RESULTS: Within the FESS group, the average slot time was reduced by 13%. 88.2% of those questioned assessed ergonomics as being better than in the conventional OR. 71.5% stated that the Surgical Deck provided an added value with regard to the surgical procedure. 91.3% confirmed that the system control required additional training. 79.3% described the cost-benefit-ratio as appropriate. For 96% of the surgeries, respondents said that they were feeling adequately supported by the technology. CONCLUSION: The results show a clear advantage of the system architecture. The Surgical Deck may present a solid foundation with regard to the transfer of the system into the clinical practice. This is relevant for new assistance functions such as process control software or navigation-based collision warning systems. It is to be expected that the project will significantly contribute to further develop the future surgical workstation and its standardization.

Effect of leukotriene inhibitors on evolution of experimental brain contusions.

AIMS: Leukotriene levels increase in cerebrospinal fluid (CSF) following controlled cortical impact (CCI) injury in rats. We investigated the impact of two different leukotriene inhibitors in the CCI model on CSF leukotriene levels, brain water content (BWC), brain swelling (BS) contusion size and cellular response. METHODS: 134 male Sprague Dawley rats were investigated at 4, 24 and 72 h after CCI for CSF leukotriene levels and BWC/BS, lesion size in T2-weighted magnetic resonance imaging and immunohistochemistry. Animals received vehicle, MK-886, an inhibitor of 5-lipoxygenase activating protein, or Boscari(®) , a mixture of boswellic acids, acting as competitive nonredox 5-lipoxygenase inhibitors before trauma and then every 8 h until sacrifice. RESULTS: The intracranial pressure (ICP) was unaffected by treatment. Boscari treatment reduced CSF leukotriene C4 increase by -45% at 4 h (P < 0.03) and increase of BWC and BS by 49% (P < 0.05) and -58% at 24 h. Treatment with both substances showed a reduction of lesion volume at 72 h by -21% (P < 0.01) in T(2) -weighted magnetic resonance imaging, which was reflected in a smaller lesion area determined from a NeuN labelled section (-17% to -20%, P < 0.05). Triple immunofluorescence and Fluoro-Jade B staining showed rarefaction of neurones, glia and vasculature in the contusion core, whereas in the pericontusional zone astro- and microglia were upregulated in the presence of dying neurones. Treatment resulted in an improved survival of NeuN labelled neurones in the pericontusional cortex (+15% to +20%, P < 0.05). CONCLUSIONS: Leukotriene inhibition should be further investigated as therapeutic option to counteract secondary growth of traumatic brain contusions and to possibly improve pericontusional neuronal survival.

Comparing brain tissue oxygen measurements and derived autoregulation parameters from different probes (Licox vs. Raumedic).

We investigated two commercially available probes for measurement of the partial pressure of brain tissue oxygen (PbrO2) and calculation of the index of brain tissue oxygen pressure reactivity (ORx) in 7 patients after aneurysmal subarachnoid hemorrhage (SAH). Simultaneous monitoring of PbrO2 using the Licox(®) probe and the multiparameter Raumedic probe (Neurovent PTO(®)), measuring PbrO2, intracranial pressure (ICP) and brain temperature (Neurovent PTO) was performed for a median of 9 days (range 7-17 days). Both probes provided stable monitoring throughout the desired period. Mean PbrO2 from Licox and Neurovent PTO was 16.1 ± 9.0 mmHg and 17.5 ± 11.9 mmHg respectively. Mean ORx was 0.35 ± 0.44 and 0.31 ± 0.43 respectively. There was a difference in the measurement of PbrO2 of -2.73 ± 10.1 mmHg (Licox - Raumedic). The difference in the two values for the calculated ORx was far smaller (0.03 ± 0.31; Licox - Raumedic) and the correlation coefficient higher than for both values of PbrO2 (0.76 for ORx vs. 0.56 for PbrO2). The calculation of the autoregulation parameter ORx seemed more independent of the measurement process than the measurement of PbrO2 itself and signifies the potential clinical importance of this parameter.

[Clinical experience with navigation functions for temporal bone surgery : interim result after 40 patients]. / Klinischer Einsatz von Navigationsfunktionen in der Felsenbeinchirurgie : Zwischenbilanz nach 40 Patienten.

PROBLEM: Although robust algorithms for registration and segmentation are available, the majority of surgical approaches to the temporal bone are nowadays made without navigation assistance. Beside instrument navigation (IN), functions such as distance control (DC) and navigated control (NC) can be used. This study analyzes the application of these navigation functionalities in lateral skull base and middle ear surgery. PATIENTS AND METHODS: A total of 41 patients with an indication of temporal bone approaches were included. The navigation was realized with an optoelectric navigation system with both non-invasive and invasive markers. Parameters such as surgical time, Level of Quality (LoQ) index, and Change of Surgical Strategy (COS) index were evaluated. RESULTS: In 14.6% of patients, the conventional mode of IN was used. In 70.7% of cases, the function DC was also used. In another 14.6% of cases, the function NC was used to control the speed of the drill. The facial nerve was the dominant segmented risk structure for active navigation. The time for setup was on average 7.78 min. The LoQ index score was on average 66 points. In 17% of the patients, surgeons evaluated the assistance mode as "necessary for the surgery". No technical-related complications were recorded. CONCLUSION: This study proves the usability of navigation technology for temporal bone surgery in clinical routine. DC and NC are two additional features for higher acceptance of navigation in microscopic surgery.

[The first clinical use of an Dynamic Registration Tool for Navigation in FESS]. / Der erste klinische Einsatz einer dynamischen (Nach-) Registrierung für die Navigation in der FESS.

BACKGROUND: The effective register accuracy in an situs issues a challenge to the employment of instrument navigation in the ENT Surgery. The idea of the initially determined process Dynamic Registration Supply (DRS) is to improve the register accuracy by the automatic, and interoperability of the register. MATERIALS AND METHODS: The aim was to determine clinical use of DRS. Opto-electrical system Navigation Panel Unit, vs. 4.0.0 with the functionality DRS was used. Experiments were carried out on 95 patients who had so called FESS. The data of a control group were available to researchers. The measuring log includes among other things following parameters: retooling time, cutting-suture time, frequency of use of the navigated pointer, frequency of additional registration. RESULTS: At least once during the procedure DRS has been activated in 85 of 95 interventions (89.5). The time required increased by 15% accumulated 189 s per intervention. The most frequently used additional registration was in the region of sphenoid sinus. The surgeons underlined that out of 95 surveys in 75 cases the DRS rendered the instrument navigation more precise, while 1% of 93 cases considered this function as unwanted. CONCLUSION: The first clinical study for use of an automatic algorithm for recognition and reduction of faulty registration of a CT, navigation was successful. The findings suggest that by using automatic intraoperative registration DRS consisting inaccuracy can be reduced. In practice this means an efficient quality improvement of the Navigation.

[Clinical experiences with an automatic collision warning system: instrument navigation in endoscopic transnasal surgery]. / Klinische Erfahrungen mit einem Kollisionswarnsystem: Instrumentennavigation in der endo- und transnasalen Chirurgie.

PROBLEM: The goal of this work is the extension of instrument navigation with a collision warning function. With the help of an additional distance display and warning system the performance of surgical navigation systems should be improved. MATERIAL AND METHODS: The collision warning system (DCS) is an extension of an optoelectric navigation system (NPU, Karl Storz GmbH&Co.KG, Tuttlingen, Germany). The measurement of situation awareness was performed on phantom models of functional endoscopic surgery of the paranasal sinuses (FESS; Phacon, Leipzig). Altogether 450 measurement pairs for the analysis of surgical accuracy to the risk structure (frontal skull base, lamina papyracea, internal carotid artery) were available. To examine the influence on the clinical process, a prospective analysis of intraoperative complications was carried out. Of the 104 FESS patients, two groups, one of 56 patients with only navigation (NAV) and one of 48 patients (NAV+DCS), were examined. Efficiency was evaluated on the basis of times for system preparation and intraoperative application. RESULTS: A significant increase in the assumed and actual distance values between instrument tip and risk structure using the collision warning system was seen at 76%. The complication rate was more favorable for the NAV+DCS group. The time needed for preparation of the navigation system with the application of the collision warning system increased on average by 48%, or 1.2 min. However, the relation between preparation time and utilization time was approximately the same at 53.5% in the NAV group and 57.4% in the NAV+DCS group. CONCLUSIONS: This work supports the clinical use and efficiency of a collision warning system as an addition to well-known instrument navigation in endo- and transnasal surgery. The segmenting algorithm is suitable for clinical requirements.

[Influence of an auto-motorised optical navigation camera to the surgical workflow in ENT surgery]. / Die Auswirkungen einer robotergeführten Navigationskamera in der HNO-Chirurgie.

BACKGROUND: With the application of optical navigation systems an interruption of the line of sight (LOS) between navigation camera and the patient/instrument can occur. The goal of this work is the clinical evaluation of a newly developed system for automatic adjusting of an optical navigation camera (Navigation Camera Assistant, NCA). NCA is a miniature robot, which is able to position the navigation camera autonomously in 2 levels. MATERIAL AND METHODS: The influence of the NCA was examined on 128 patients: 55 procedures at the paranasal sinuses and 9 procedures at the temporal bone with the NCA were evaluated and compared with available workflow data of adequate surgeries without NCA. An optical navigation system of the 3 (rd) generation was used. The following parameters were recorded: Preparation time of the system, time of using the system, LOS-interruptions. RESULTS: The LOS-interruption decreased in the group of FESS with application of the NCA by 92%, in the group tympanic cavity by 85%. The number of corrective motions of the navigation camera was increased with application of the NCA in the group FESS by 73%, in the group tympanic cavity by 89%. The usage time of navigation increased with the application of the NCA in the group of FESS by 36%, in the group tympanic cavity by 16%. CONCLUSIONS: With a motorized navigation camera can be the interruption rate of LOS significantly improved at frontal and lateral skull base. The technical expenditure for installation of the NCA robot is little even during, for this reason there is the potential that this module can be established for the clinical practice.

Coincidence of immune thrombocytopenia, intracranial hemorrhage and graft-versus-host disease in an 11-year-old girl.

Primary immune thrombocytopenia (ITP) in children is usually self-limiting and harmless but can, rarely, result in life-threatening complications. The case of an 11-year-old girl with ITP is presented who developed recurrent intracranial hemorrhages followed by cerebral infarctions. The clinical course was complicated by a graft-versus-host disease involving several organs. Treatment was performed according to the current international consensus report of 2010 with glucocorticoids, immunoglobulin G, anti-D-immunoglobulin and additionally embolisation of the splenic artery. The girl survived. Reliable predictors, preventive measures for life-threatening complications in ITP and more information about the effectiveness and side-effects of the recommended treatment are urgently needed.

[Conception, realization and analysis of a modern operating theatre workplace for ENT surgery]. / Konzeption, Realisierung und Analyse einer neuartigen OP-Konzeption für die HNO-Chirurgie.

BACKGROUND: The requirements of ENT (ear, nose and throat) surgery, i. e. operating theatre, have changed dramatically in recent years, e. g. by high definition video endoscopy, navigation, neuromonitoring, intraoperative imaging, navigated and navigation-controlled instruments and intraoperative imaging and video documentation. For this reason a specialized operating theatre is necessary for ENT. The aim of this work was to compare this operating theatre with the previous standard. MATERIAL AND METHODS: The scientific basis of this work represents a surgical workflow analysis. Over 200 completely documented operations in conventional operating theatres were available for comparison. In addition the log files of the medical technical devices, software analysis modules of the clinical documentation and ergonomics questionnaires (NASA TLX standard) were available. In the period from 1(st) June 2009 to 31(st) September 2009 a total of 139 standard procedures (9 different ENT surgeons) were analyzed in the new ly integrated operating theatre system "Surgical Deck1-ENT". RESULTS: In the newly developed operating theatre system four work areas are specified: preparation area, technical cockpit, surgical cockpit and anesthesia cockpit. The medical technical components are permanently installed. The surgical cockpit incorporates five permanently arranged monitors, two main screens, two navigation screens and a surgical dashboard. A suitable high definition video routing system is installed and procedure-specific light profiles are developed. Documentation is automatically carried out in the picture archive and communication system (PACS). The comparison to the conventional operating theatre system the slot time was reduced from 73.8 min to 65.6 min (-11%), the preoperative time was reduced on average by 31% (8 min) per case and the documentation time was decreased on average by 6 min (67%). The interaction steps of the surgeon with the system were reduced by 70% (from 17 to 5 steps). No significant differences in complications could be observed. In the total evaluation of all 16 questions on the ergonomics there was a significant improvement of the workplace layout. DISCUSSION: The presented operation unit can significantly improve safety and efficiency as well as the ergonomics for ENT surgery and related procedures.