Structure of Neurosurgical Care in Germany in Comparison to Countries Organized in the European Association of Neurosurgical Societies: A Need to Reorganize Neurosurgical Training and Care in Germany.

BACKGROUND: Although the world is experiencing a deficit in the neurosurgical workforce, the number of neurosurgeons in Germany has increased within the last two decades. The aim of the present study was to assess the neurosurgical workforce in Germany, compare it to European countries, and assess structures in neurosurgical departments in Germany. METHODS: Data regarding the number of neurosurgeons in Germany as well as the number of departments, beds, cases, and neurosurgical procedures were gathered. A survey among German neurosurgical departments was performed to assess the structure of neurosurgical care. Furthermore, another survey among European countries was performed to acquire information regarding the number of surgeons and the regulation of training. RESULTS: From 2000 to 2019, the number of board-certified neurosurgeons in Germany increased by 151% from 973 to 2,446. During the same period, the German population increased by only 1% from 82.26 million to 83.17 million. Thus, the number of neurosurgeons per 100,000 inhabitants increased from 1.18 to 2.94. The increase of neurosurgeons is not paralleled by an increase in departments or an increase in neurosurgical procedures within the active neurosurgical departments. In comparison to the participating European countries, where the number of neurosurgeons per 100,000 inhabitants ranged from 0.45 to 2.94, with Germany shows the highest number. CONCLUSIONS: German institutions of medical administration urgently need to consider regulation of neurosurgical specialist training to prevent a further uncontrolled increase in neurosurgeons in a manner that is not adapted to the needs of neurosurgical care for the German population. Actions might include a regulation of entry to the training and of the number of training sites. Furthermore, an integration of non-physician assistant health care professionals and delegation of non-surgical workload from neurosurgeons is necessary. A further increase in neurosurgeons would be associated with a decrease in the surgical caseload per surgeons during training and after board certification, which might compromise the quality of neurosurgical care.

The effects of lumbar fusion and non-fusion surgery on the development of Modic changes.

BACKGROUND: The aim of this study was to investigate the influence of lumbar fusion and non-fusion surgery on the postoperative development of Modic changes (MCs). METHODS: A total of 270 patients who underwent lumbar fusion, microsequestrectomy, microdiscectomy, and microdecompression, and who were examined by pre- and postoperative magnetic resonance imaging during the period of January 2012 to December 2018, were included in this retrospective study. The incidence of new postoperative MCs and the change of volume of preexisting MCs after surgery were investigated. RESULTS: The total incidence of new MCs following lumbar surgical procedures was 36.3%. Lumbar fusion showed a tendency towards a lower postoperative incidence of new MCs than the other three lumbar surgical procedures. The first postoperative year seems to be the most active phase for the development of new MCs. The postoperative volumes of MCs in patients who underwent lumbar non-fusion procedures were significantly greater than those before surgery (P < 0.01). However, no significant difference was detected between pre- and postoperative volumes of MCs in patients with lumbar fusion (P > 0.05). CONCLUSION: Lumbar surgical procedures contribute to the development of new MCs, particularly non-fusion surgeries. However, further studies are needed to confirm the clinical relevance of these findings.

Serum Biomarkers for Risk Assessment of Intrahospital Transports in Mechanically Ventilated Neurosurgical Intensive Care Unit Patients.

OBJECTIVE: Intrahospital transports (IHTs) of neurosurgical intensive care unit (NICU) patients can be hazardous. Increasing intracranial pressure (ICP) and/or decreasing cerebral perfusion pressure (CPP) as well as cardiopulmonary alterations are common complications of an IHTs, which can lead to secondary brain injury. This study was performed to assess several serum biomarkers concerning their potential to improve safety of IHTs in mechanically ventilated NICU patients. METHODS: All IHTs of mechanically ventilated and sedated NICU patients from 03/2017 to 01/2018 were retrospectively analyzed. Intracranial pressure and CPP measurements were performed in all patients. Serum hemoglobin, hematocrit, and serum sodium were defined as serum biomarkers. Demographic data, computed tomography scan on admission, Simplified Acute Physiology Score and Acute Physiology and Chronic Health Evaluation II, modified Rankin Scale, indication and consequence of IHTs were analyzed. Alteration of ICP/CPP, hemodynamic and pulmonary events were defined as complications. The study population was stratified into patients with the occurrence of a complication and absence of a complication. RESULTS: We analyzed a total number of 184 IHTs in 70 NICU patients with an overall complication rate of 57.6%. Of all, 32.1% IHTs had no direct therapeutic consequence. In patients with higher hemoglobin values prior to IHT less complications occurred, concerning ICP (P = .001), CPP (P = .001), hemodynamic (P = .005), and pulmonary (P < .0001) events. In addition, complications concerning ICP (P = .001), CPP (P = .001), hemodynamic (P = .005), and pulmonary problems (P = .002) were significantly lower in patients with higher hematocrit values before IHT. CONCLUSION: Intrahospital transports of mechanically ventilated NICU patients carry a high risk of increased ICP and hemodynamic complications and should be performed restrictively. Higher values of hemoglobin and hematocrit prior to IHT were associated with less complications with regard to ICP, CPP as well as hemodynamic and pulmonary events and could be helpful to assess the potential risk of complications prior to IHTs.

Correlation of Modic Changes with Sagittal Lumbopelvic Parameters.

PURPOSE: The main aim of this retrospective study was to analyze lumbopelvic sagittal parameters among the three different types of Modic changes (MCs). Furthermore, correlations between the sizes of MCs and the number of involved lumbar levels with lumbopelvic parameters are investigated. METHODS: A total of 263 adult subjects with MCs at a single institution from September 2015 to October 2020 who underwent lumbar x-ray examinations and magnetic resonance imaging were included in this retrospective study. Types of MCs, sizes of MCs, lumbar levels involved by MCs as well as lumbopelvic sagittal parameters from each subject were evaluated by two authors. RESULTS: Lumbar lordosis (LL), sacral slope (SS), and pelvic incidence (PI) in subjects with MC grade 1 were significantly smaller than in those with MC grade 2 and grade 3 (p<0.05). Lumbopelvic sagittal parameters decreased significantly as the sizes aggravated (p<0.01). Triple lumbar levels with MCs showed a significant increase in PI-LL (p<0.05) and decrease in LL (p<0.01), SS (p<0.01), and PI (p<0.01) when compared to MCs at single and double lumbar levels. CONCLUSION: MC grade 1, severe MCs, and lumbar multi-segmental MCs were significantly linked to lumbar sagittal imbalance.

Troponin I as an early biomarker of cardiopulmonary parameters during the first 24 h of intensive care unit treatment in isolated traumatic brain injury patients.

OBJECTIVE: Cardiopulmonary (CP) complications are well-known phenomena after an isolated traumatic brain injury (iTBI) and they may be associated with an elevated serum troponin I (TnI) value. However, the influence of an elevated TnI level on CP parameters within the first 24 h after an iTBI is still unknown. The current study was conducted to assess the associations between the initial TnI value on admission and CP parameters during the first 24 h of intensive care unit (ICU) treatment in iTBI patients. PATIENTS AND METHODS: A total of 288 patients with iTBIs, who were admitted to our emergency department between January 2010 and November 2016 were retrospectively analyzed. Blood samples were taken on admission to determine TnI value. Each patient's demographic data, treatment regime, computed tomography results, and intra-hospital outcomes were evaluated, as well as several CP parameters, within the first 24 h of ICU treatment. The entire study population was stratified into patients with an initial TnI elevation (TnI positive) and without an initial TnI elevation (TnI negative). RESULTS: Increased TnI values on admission were found in 59 (20.5%) patients. There were significant correlations between an initially elevated TnI value and a lower Glasgow Coma Scale score (p = 0.003), higher head Abbreviated Injury Scale score (p<0.0001), and higher Acute Physiology and Chronic Health Evaluation II score (p = 0.005) on admission, as well as a lower Glasgow Outcome Scale score (p = 0.0002) and higher modified Rankin Scale score (p = 0.0001) at discharge. In addition, a significantly higher norepinephrine application rate (NAR) (p<0.0001) and inspiratory oxygen fraction (FiO2) (p = 0.028) were needed in the TnI positive group. CONCLUSION: Patients with elevated TnI values on admission require more circulation support (NAR and FiO2) within the first 24 h of ICU treatment after an iTBI. Therefore, the TnI may be a useful biomarker to improve ICU treatment of these patients.

Diffusion Tensor Imaging for Surgical Planning in Patients with Cervical Spondylotic Myelopathy.

BACKGROUND AND STUDY AIMS/OBJECTIVE: Despite its invasiveness, computed tomography myelography (CTM) is still considered an important supplement to conventional magnetic resonance imaging (MRI) for preoperative evaluation of multilevel cervical spondylotic myelopathy (CSM). We analyzed if diffusion tensor imaging (DTI) could be a less invasive alternative for this purpose. MATERIAL AND METHODS: In 20 patients with CSM and an indication for decompression of at least one level, CTM was performed preoperatively to determine the extent of spinal canal/cerebrospinal fluid (CSF) space and cord compression (Naganawa score) for a decision on the number of levels to be decompressed. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were correlated with these parameters and with MRI-based increased signal intensity (ISI). Receiver operating characteristic analysis was performed to determine the sensitivity to discriminate levels requiring decompression surgery. European Myelopathy Score (EMS) and neck/radicular visual analog scale (VAS-N/R) were used for clinical evaluation. RESULTS: According to preoperative CTM, 20 levels of maximum and 16 levels of relevant additional stenosis were defined and decompressed. Preoperative FA and particularly ADC showed a significant correlation with the CTM Naganawa score but also with the ISI grade. Furthermore, both FA and ADC facilitated a good discrimination between stenotic and nonstenotic levels with cutoff values < 0.49 for FA and > 1.15 × 10-9 m2/s for ADC. FA and especially ADC revealed a considerably higher sensitivity (79% and 82%, respectively) in discriminating levels requiring decompression surgery compared with ISI (55%). EMS and VAS-N/R were significantly improved at 14 months compared with preoperative values. CONCLUSION: DTI parameters are highly sensitive at distinguishing surgical from nonsurgical levels in CSM patients and might therefore represent a less invasive alternative to CTM for surgical planning.

Implementation of Transforaminal Endoscopic Lumbar Sequestrectomy in a German University Hospital Setting: A Long and Rocky Road.

OBJECTIVE: Microsurgical diskectomy/sequestrectomy is the standard procedure for the surgical treatment of lumbar disk herniations. The transforaminal endoscopic sequestrectomy technique is a minimally invasive alternative with potential advantages such as minimal blood loss and tissue damage, as well as early mobilization of the patient. We report the implementation of this technique in a German university hospital setting. METHODS: One single surgeon performed transforaminal endoscopic sequestrectomy from February 2013 to July 2016 for lumbar disk herniation in 44 patients. Demographic as well as perioperative, clinical, and radiologic data were analyzed from electronic records. Furthermore, we investigated complications, intraoperative change of the procedure to microsurgery, and reoperations. The postoperative course was analyzed using the Macnab criteria, supplemented by a questionnaire for follow-up. Pre- and postoperative magnetic resonance imaging volumetric analyses were performed to assess the radiologic efficacy of the technique. RESULTS: Our study population had a median age of 52 years. The median follow-up was 15 months, and the median length of hospital stay was 4 days. Median duration of surgery was 100 minutes with a median blood loss of 50 mL. Surgery was most commonly performed at the L4-L5 level (63%) and in caudally migrated disk herniations (44%). In six patients, surgery was performed for recurrent disk herniations. The procedure had to be changed to conventional microsurgery in four patients. We observed no major complications. Minor complications occurred in six patients, and in four patients a reoperation was performed. Furthermore, a significantly lower Oswestry Disability Index score (p = 0.03), a lower Short Form 8 Health Survey (SF-8) score (p = 0.001), a lower visual analog scale (VAS) lower back pain score (p = 0.03) and VAS leg pain score (p = 0.0008) at the 12-month follow-up were observed in comparison with the preoperative examination. In MRI volumetry, we detected a median postoperative volume reduction of the disk herniation of 57.1% (p = 0.02). CONCLUSIONS: The transforaminal endoscopic sequestrectomy can be safely implemented in a university hospital setting in selected patients with primary and recurrent lumbar disk herniations, and it leads to good clinical and radiologic results. However, learning curve, caseload, and residents' microsurgical training requirements clearly affect the implementation process.

Neurosurgery in East Africa: Foundations.

This article is the first in a series of 3 articles that seek to provide readers with an understanding of the development of neurosurgery in East Africa (Foundations), the challenges that arise in providing neurosurgical care in developing countries (Challenges), and an overview of traditional and novel approaches to overcoming these challenges to improve healthcare in the region (Innovations). We review the history and evolution of neurosurgery as a clinical specialty in East Africa. We also review Kenya, Uganda, and Tanzania in some detail and highlight contributions of individuals and local and regional organizations that helped to develop and shape neurosurgical care in East Africa. Neurosurgery has developed steadily as advanced techniques have been adopted by local surgeons who trained abroad, and foreign surgeons who have dedicated part of their careers in local hospitals. New medical schools and surgical training programs have been established through regional and international partnerships, and the era of regional specialty surgical training has just begun. As more surgical specialists complete training, a comprehensive estimation of disease burden facing the neurosurgical field is important. We present an overview with specific reference to neurotrauma and neural tube defects, both of which are of epidemiologic importance as they gain not only greater recognition, but increased diagnoses and demands for treatment. Neurosurgery in East Africa is poised to blossom as it seeks to address the growing needs of a growing subspecialty.

Neurosurgery in East Africa: Innovations.

In the last 10 years, considerable work has been done to promote and improve neurosurgical care in East Africa with the development of national training programs, expansion of hospitals and creation of new institutions, and the foundation of epidemiologic and cost-effectiveness research. Many of the results have been accomplished through collaboration with partners from abroad. This article is the third in a series of articles that seek to provide readers with an understanding of the development of neurosurgery in East Africa (Foundations), the challenges that arise in providing neurosurgical care in developing countries (Challenges), and an overview of traditional and novel approaches to overcoming these challenges to improve healthcare in the region (Innovations). In this article, we describe the ongoing programs active in East Africa and their current priorities, and we outline lessons learned and what is required to create self-sustained neurosurgical service.

The Growth of Neurosurgery in East Africa: Challenges.

As the second of 3 articles in this series, the aim of this article is to provide readers with an understanding of the development of neurosurgery in East Africa (foundations), the challenges that arise in providing neurosurgical care in developing countries (challenges), and an overview of traditional and novel approaches to overcoming these challenges and improving health care in the region (innovations). Recognizing the challenges that need to be addressed is the first step to implementing efficient and qualified surgery delivery systems in low- and middle-income countries. We reviewed the major challenges facing health care in East Africa and grouped them into 5 categories: 1) burden of surgical disease and workforce crisis; 2) global health view of surgery as "the neglected stepchild"; 3) need for recognizing the surgical system as an interdependent network and importance of organizational and equipment deficits; 4) lack of education in the community, failure of primary care systems, and net result of overwhelming tertiary care systems; 5) personal and professional burnout as well as brain drain of promising human resources from low- and middle-income countries in East Africa and similar regions across the world. Each major challenge was detailed and analyzed by authors who have worked or are currently working in the region, providing a personal perspective.

Microvasospasms After Experimental Subarachnoid Hemorrhage Do Not Depend on Endothelin A Receptors.

BACKGROUND AND PURPOSE: Perturbations in cerebral microcirculation (eg, microvasospasms) and reduced neurovascular communication determine outcome after subarachnoid hemorrhage (SAH). ET-1 (endothelin-1) and its receptors have been implicated in the pathophysiology of large artery spasms after SAH; however, their role in the development of microvascular dysfunction is currently unknown. Here, we investigated whether inhibiting ETA (endothelin A) receptors can reduce microvasospasms after experimentally induced SAH. METHODS: SAH was induced in male C57BL/6 mice by filament perforation of the middle cerebral artery. Three hours after SAH, a cranial window was prepared and the pial and parenchymal cerebral microcirculation was measured in vivo using two-photon microscopy before, during, and after administration of the ETA receptor inhibitor clazosentan. In separate experiments, the effect of clazosentan treatment on neurological outcome was measured 3 days after SAH. RESULTS: Clazosentan treatment had no effect on the number or severity of SAH-induced cerebral microvasospasms nor did it affect neurological outcome. CONCLUSIONS: Our results indicate that ETA receptors, which mediate large artery spasms after SAH, do not seem to play a role in the development of microarterial spasms, suggesting that posthemorrhagic spasms are mediated by distinct mechanisms in large and small cerebral vessels. Given that cerebral microvessel dysfunction is a key factor for outcome after SAH, further research into the mechanisms that underlie posthemorrhagic microvasospasms is urgently needed.

Cerebral Alterations Following Experimental Multiple Trauma and Hemorrhagic Shock.

Multiple trauma (MT) associated with hemorrhagic shock (HS) might lead to cerebral hypoperfusion and brain damage. We investigated cerebral alterations using a new porcine MT/HS model without traumatic brain injury (TBI) and assessed the neuroprotective properties of mild therapeutic hypothermia. Male pigs underwent standardized MT with HS (45% or 50% loss of blood volume) and resuscitation after 90/120 min (T90/T120). In additional groups (TH90/TH120) mild hypothermia (33°C) was induced following resuscitation. Normothermic or hypothermic sham animals served as controls. Intracranial pressure, cerebral perfusion pressure (CPP), and cerebral oxygenation (PtiO2) were recorded up to 48.5 h. Serum protein S-100B and neuron-specific enolase (NSE) were measured by ELISA. Cerebral inflammation was quantified on hematoxylin and eosin -stained brain slices; Iba1, S100, and inducible nitric oxide synthase (iNOS) expression was assessed using immunohistochemistry. Directly after MT/HS, CPP and PtiO2 were significantly lower in T90/T120 groups compared with sham. After resuscitation both parameters showed a gradual recovery. Serum protein S-100B and NSE increased temporarily as a result of MT/HS in T90 and T90/T120 groups, respectively. Cerebral inflammation was found in all groups. Iba1-staining showed significant microgliosis in T90 and T120 animals. iNOS-staining indicated a M1 polarization. Mild hypothermia reduced cerebral inflammation in the TH90 group, but resulted in increased iNOS activation. In this porcine long-term model, we did not find evidence of gross cerebral damage when resuscitation was initiated within 120 min after MT/HS without TBI. However, trauma-related microglia activation and M1 microglia polarization might be a consequence of temporary hypoxia/ischemia and further research is warranted to detail underlying mechanisms. Interestingly, mild hypothermia did not exhibit neuroprotective properties when initiated in a delayed fashion.

Ten-Step Minimally Invasive Spine Lumbar Decompression and Dural Repair Through Tubular Retractors.

BACKGROUND: Minimally invasive spine (MIS) surgery utilizing tubular retractors has become an increasingly popular approach for decompression in the lumbar spine. However, a better understanding of appropriate indications, efficacious surgical techniques, limitations, and complication management is required to effectively teach the procedure and to facilitate the learning curve. OBJECTIVE: To describe our experience and recommendations regarding tubular surgery for lumbar disc herniations, foraminal compression with unilateral radiculopathy, lumbar spinal stenosis, synovial cysts, and dural repair. METHODS: We reviewed our experience between 2008 and 2014 to develop a step-by-step description of the surgical techniques and complication management, including dural repair through tubes, for the 4 lumbar pathologies of highest frequency. We provide additional supplementary videos for dural tear repair, laminotomy for bilateral decompression, and synovial cyst resection. RESULTS: Our overview and complementary materials document the key technical details to maximize the success of the 4 MIS surgical techniques. The review of our experience in 331 patients reveals technical feasibility as well as satisfying clinical results, with no postoperative complications associated with cerebrospinal fluid leaks, 1 infection, and 17 instances (5.1%) of delayed fusion. CONCLUSION: MIS surgery through tubular retractors is a safe and effective alternative to traditional open or microsurgical techniques for the treatment of lumbar degenerative disease. Adherence to strict microsurgical techniques will allow the surgeon to effectively address bilateral pathology while preserving stability and minimizing complications.

Lumbar Spinal Stenosis Associated With Degenerative Lumbar Spondylolisthesis: A Systematic Review and Meta-analysis of Secondary Fusion Rates Following Open vs Minimally Invasive Decompression.

Background: Decompression without fusion is a treatment option in patients with lumbar spinal stenosis (LSS) associated with stable low-grade degenerative spondylolisthesis (DS). A minimally invasive unilateral laminotomy (MIL) for "over the top" decompression might be a less destabilizing alternative to traditional open laminectomy (OL). Objective: To review secondary fusion rates after open vs minimally invasive decompression surgery. Methods: We performed a literature search in Pubmed/MEDLINE using the keywords "lumbar spondylolisthesis" and "decompression surgery." All studies that separately reported the outcome of patients with LSS+DS that were treated by OL or MIL (transmuscular or subperiosteal route) were included in our systematic review and meta-analysis. The primary end point was secondary fusion rate. Secondary end points were total reoperation rate, postoperative progression of listhetic slip, and patient satisfaction. Results: We identified 37 studies (19 with OL, 18 with MIL), with a total of 1156 patients, that were published between 1983 and 2015. The studies' evidence was mostly level 3 or 4. Secondary fusion rates were 12.8% after OL and 3.3% after MIL; the total reoperation rates were 16.3% after OL and 5.8% after MIL. In the OL cohort, 72% of the studies reported a slip progression compared to 0% in the MIL cohort, respectively. After OL, satisfactory outcome was 62.7% compared to 76% after MIL. Conclusion: In patients with LSS and DS, minimally invasive decompression is associated with lower reoperation and fusion rates, less slip progression, and greater patient satisfaction than open surgery.

Application of a Compact High-Definition Exoscope for Illumination and Magnification in High-Precision Surgical Procedures.

BACKGROUND: The basic necessities for surgical procedures are illumination, exposure, and magnification. These have undergone transformation in par with technology. One of the recent developments is the compact magnifying exoscope system. In this report, we describe the application of this system for surgical operations and discuss its advantages and pitfalls. METHODS: We used the ViTOM exoscope mounted on the mechanical holding arm. The following surgical procedures were conducted: lumbar and cervical spinal canal decompression (n = 5); laminotomy and removal of lumbar migrated disk herniations (n = 4); anterior cervical diskectomy and fusion (n = 1); removal of intraneural schwannomas (n = 2); removal of an acute cerebellar hemorrhage (n = 1); removal of a parafalcine atypical cerebral hematoma caused by a dural arteriovenous fistula (n = 1); and microsutures and anastomoses of a nerve (n = 1), an artery (n = 1), and veins (n = 2). RESULTS: The exoscope offered excellent, magnified, and brilliantly illuminated high-definition images of the surgical field. All surgical operations were successfully completed. The main disadvantage was the adjustment and refocusing using the mechanical holding arm. The time required for the surgical operation under the exoscope was slightly longer than the times required for a similar procedure performed using an operating microscope. CONCLUSIONS: The magnifying exoscope is an effective and nonbulky tool for surgical procedures. In visualization around the corners, the exoscope has better potential than a microscope. With technical and technologic modifications, the exoscope might become the next generation in illumination, visualization, exposure, and magnification for high-precision surgical procedures.

Microsurgical unilateral laminotomy for decompression of lumbar spinal stenosis: long-term results and predictive factors.

BACKGROUND: The microsurgical unilateral laminotomy (MUL) technique for bilateral decompression of lumbar spinal stenosis (LSS) is a less destabilizing alternative to laminectomy and leads to good short-term outcomes. However, little is known about the long-term results including predictive factors. METHODS: Medical records of patients who underwent MUL for LSS decompression between 2005 and 2010 were reviewed, and a questionnaire was distributed to complement the long-term outcome data. The study population consisted of 176 patients including 17 patients with stable grade I spondylolisthesis. Complications and reoperations were meticulously analyzed. Clinical outcome was measured using a modified Prolo scale and was further dichotomized in good vs. poor outcome. Predictive factors were obtained from uni- and multivariate analyses. RESULTS: The median age of the cohort was 70.0 years and the follow-up 71.7 months. Complications occurred in 5.1 % of the patients. The overall reoperation rate was 17.0 %, including surgery, which was exclusively performed at other levels in 4.0 %. The reoperation rate for fusion was 4.5 %. Good neurogenic claudication outcome faded from 98.3 % at hospital discharge to 47.2 % at 6 years. Multivariate analysis identified previous lumbar operation as a potential independent predictor of a reoperation; potential independent predictors of poor long-term claudication outcome were older age, female gender, higher body mass index (BMI) and tobacco smoking. CONCLUSIONS: In our experience, the long-term reoperation rate after MUL for LSS is not negligible and higher in previously operated patients. It seems like the good initial clinical results after MUL may fade over time, and several patient-related predictive factors including potentially modifiable obesity and tobacco smoking seem to play an important role.

Nitric oxide inhalation reduces brain damage, prevents mortality, and improves neurological outcome after subarachnoid hemorrhage by resolving early pial microvasospasms.

Subarachnoid hemorrhage is a stroke subtype with particularly bad outcome. Recent findings suggest that constrictions of pial arterioles occurring early after hemorrhage may be responsible for cerebral ischemia and - subsequently - unfavorable outcome after subarachnoid hemorrhage. Since we recently hypothesized that the lack of nitric oxide may cause post-hemorrhagic microvasospasms, our aim was to investigate whether inhaled nitric oxide, a treatment paradigm selectively delivering nitric oxide to ischemic microvessels, is able to dilate post-hemorrhagic microvasospasms; thereby improving outcome after experimental subarachnoid hemorrhage. C57BL/6 mice were subjected to experimental SAH. Three hours after subarachnoid hemorrhage pial artery spasms were quantified by intravital microscopy, then mice received inhaled nitric oxide or vehicle. For induction of large artery spasms mice received an intracisternal injection of autologous blood. Inhaled nitric oxide significantly reduced number and severity of subarachnoid hemorrhage-induced post-hemorrhage microvasospasms while only having limited effect on large artery spasms. This resulted in less brain-edema-formation, less hippocampal neuronal loss, lack of mortality, and significantly improved neurological outcome after subarachnoid hemorrhage. This suggests that spasms of pial arterioles play a major role for the outcome after subarachnoid hemorrhage and that lack of nitric oxide is an important mechanism of post-hemorrhagic microvascular dysfunction. Reversing microvascular dysfunction by inhaled nitric oxide might be a promising treatment strategy for subarachnoid hemorrhage.

Microsurgical fenestration of idiopathic intramedullary cysts in adult patients.

PURPOSE: The aim of this study is to describe the findings in one of the largest series of microsurgically treated intramedullary cysts investigated by magnetic resonance imaging (MRI), focusing on the peri- and intraoperative setup including detailed neurological and radiological outcome analyses. METHODS: Retrospective analysis of patients with intramedullary cyst who had undergone microsurgical fenestration at our department between 2006 and 2011. Preoperative three-dimensional constructive interference of steady-state MRI was conducted to optimize surgical planning. Intraoperative electrophysiological monitoring included motor-evoked potentials, somatosensory-evoked potentials, and electromyogram. Clinical outcome as well as pre-, postoperative and long-term MRI scans were evaluated. RESULTS: Eight female patients (median age 58.0 years, range 32-72 years) with a median clinical follow-up of 48.0 months (range 2-69 months) were included. Seven cysts were located in the conus medullaris, one in the cervical spine. Overall, 25.0% (2/8) showed complete remission of preoperative symptoms, 62.5% (5/8) improved, and 12.5% (1/8) asymptomatic patients remained unchanged. Pain syndromes (4/4) as well as motor deficits (2/2) improved in all affected patients and bladder dysfunction (3/4) displayed a high tendency for improvement. Postoperative MRI scans showed permanently decreased cyst volumes by ~80%. CONCLUSION: Microsurgical fenestration of intramedullary cysts using preoperative high-resolution imaging and intraoperative electrophysiological monitoring is a safe and effective treatment option for symptomatic patients.

Aneurysmal subarachnoid hemorrhage in elderly patients: long-term outcome and prognostic factors in an interdisciplinary treatment approach.

The number of elderly patients with aneurysmal subarachnoid hemorrhage (SAH) is increasing with the aging of the population. However, management recommendations based on long-term outcome data and analyses of prognostic factors are scarce. Our study focused exclusively on elderly patients aged ≥ 60 years at the onset of SAH. Patients were selected from an in-house database and compared in cohorts of age 60-69, 70-79, and ≥ 80, regarding pre-existing medical conditions, treatment, clinical course including complications, and outcome. A multivariate analysis was conducted to identify prognostic factors for death and disability. A total of 256 patients (138 aged 60-69, 93 aged 70-79, 25 aged ≥ 80) with putative aneurysmal SAH who had been admitted to our hospital between January 1, 1996 and June 30, 2007 were extracted. The median follow-up of our total cohort was 35.5 months (range <1-154 months). Endovascular or conservative aneurysm treatment was applied more often with increasing age (p < 0.006). The 1-year survival rate was 78, 65, and 38 % in the three age groups, respectively (p = 0.0002); most of the patients died from the initial hemorrhage or from medical complications. Patients aged <70 with an initial World Federation of Neurosurgical Societies (WFNS) score of I-III showed the best clinical recovery. WFNS score, age, and clipping/coiling were extracted as prognostic factors from the Cox model. Elderly patients who get admitted with a good WFNS score (I-III) seem to benefit from aggressive treatment whereas caution seems to be warranted particularly in patients ≥ 70 years of age who get admitted in a WFNS score of IV and V because of their limited short- and long-term prognosis.

Impact of anesthesia on pathophysiology and mortality following subarachnoid hemorrhage in rats.

BACKGROUND: Anesthesia is indispensable for in vivo research but has the intrinsic potential to alter study results. The aim of the current study was to investigate the impact of three common anesthesia protocols on physiological parameters and outcome following the most common experimental model for subarachnoid hemorrhage (SAH), endovascular perforation. METHODS: Sprague-Dawley rats (n = 38) were randomly assigned to (1) chloral hydrate, (2) isoflurane or (3) midazolam/medetomidine/fentanyl (MMF) anesthesia. Arterial blood gases, intracranial pressure (ICP), mean arterial blood pressure (MAP), cerebral perfusion pressure (CPP), and regional cerebral blood flow (rCBF) were monitored before and for 3 hours after SAH. Brain water content, mortality and rate of secondary bleeding were also evaluated. RESULTS: Under baseline conditions isoflurane anesthesia resulted in deterioration of respiratory parameters (arterial pCO2 and pO2) and increased brain water content. After SAH, isoflurane and chloral hydrate were associated with reduced MAP, incomplete recovery of post-hemorrhagic rCBF (23 ± 13% and 87 ± 18% of baseline, respectively) and a high anesthesia-related mortality (17 and 50%, respectively). Anesthesia with MMF provided stable hemodynamics (MAP between 100-110 mmHg), high post-hemorrhagic rCBF values, and a high rate of re-bleedings (> 50%), a phenomenon often observed after SAH in humans. CONCLUSION: Based on these findings we recommend anesthesia with MMF for the endovascular perforation model of SAH.