Direct subthalamic nucleus stimulation influences speech and voice quality in Parkinson's disease patients.

BACKGROUND: DBS of the subthalamic nucleus (STN) considerably ameliorates cardinal motor symptoms in PD. Reported STN-DBS effects on secondary dysarthric (speech) and dysphonic symptoms (voice), as originating from vocal tract motor dysfunctions, are however inconsistent with rather deleterious outcomes based on post-surgical assessments. OBJECTIVE: To parametrically and intra-operatively investigate the effects of deep brain stimulation (DBS) on perceptual and acoustic speech and voice quality in Parkinson's disease (PD) patients. METHODS: We performed an assessment of instantaneous intra-operative speech and voice quality changes in PD patients (n = 38) elicited by direct STN stimulations with variations of central stimulation features (depth, laterality, and intensity), separately for each hemisphere. RESULTS: First, perceptual assessments across several raters revealed that certain speech and voice symptoms could be improved with STN-DBS, but this seems largely restricted to right STN-DBS. Second, computer-based acoustic analyses of speech and voice features revealed that both left and right STN-DBS could improve dysarthric speech symptoms, but only right STN-DBS can considerably improve dysphonic symptoms, with left STN-DBS being restricted to only affect voice intensity features. Third, several subareas according to stimulation depth and laterality could be identified in the motoric STN proper and close to the associative STN with optimal (and partly suboptimal) stimulation outcomes. Fourth, low-to-medium stimulation intensities showed the most optimal and balanced effects compared to high intensities. CONCLUSIONS: STN-DBS can considerably improve both speech and voice quality based on a carefully arranged stimulation regimen along central stimulation features.

Intraoperative radiotherapy after resection of brain metastases located in the posterior fossa. Analysis of postoperative morbidity and mortality in a single center cohort.

INTRODUCTION: In order to improve surgical outcome and accelerate the adjuvant oncologic therapy, intraoperative Radiotherapy (IORT) has become a treatment option in oncologic surgery for various diseases including glioma and brain metastasis (BM). BMs are often located in the cranial posterior fossa (PF) requiring specific surgical considerations due to its complex anatomy. Up until now, data on IORT for BMs is limited and detailed description in the use of IORT for lesions in the PF is lacking. Our aim is to provide more insight into this emerging treatment strategy. METHODS: We performed a retrospective analysis of patients receiving surgery for BMs and undergoing IORT at our institution. Each patient was discussed at the interdisciplinary tumor board decision before the intervention. Patient characteristics, functional status (Karnofsky Performance Score, KPS) before and after surgery, disease (recursive partitioning analysis, lesion size) and operative parameters were analyzed. Adverse events (AE) were recorded up until 30 days after the intervention and rated according to the Clavien Dindo Rating scale. RESULTS: Nine patients (5 female) were included. None underwent prior radiotherapy (RT). Mean age was 66 ± 11 years. Preoperative median KPS was 80%. Mean BM diameter was 3.2 ± 0.9 cm. There was no statistically significant deterioration of the functional status after the intervention. Two patients experienced AEs with both of them needing revision surgery. CONCLUSION: Surgery for BMs with IORT in the PF seems safe and feasible. Further studies are needed to evaluate the influence of IORT on long-term outcome after BM surgery.

Management of perimesencephalic nonaneurysmal subarachnoid hemorrhage: a national survey.

Perimesencephalic nonaneurysmal subarachnoid hemorrhage (NASAH) is a rare type of subarachnoid hemorrhage (SAH), usually associated with minor complications compared to aneurysmal SAH. Up to date, data is scarce and consensus on therapeutic management and follow-up diagnostics of NASAH is often missing. This survey aims to evaluate the clinical management among neurosurgical departments in Germany. 135 neurosurgical departments in Germany received a hardcopy questionnaire. Encompassing three case vignettes with minor, moderate and severe NASAH on CT-scans and questions including the in-hospital treatment with initial observation, blood pressure (BP) management, cerebral vasospasm (CV) prophylaxis and the need for digital subtraction angiography (DSA). 80 departments (59.2%) answered the questionnaire. Whereof, centers with a higher caseload state an elevated complication rate (Chi2 < 0.001). Initial observation on the intensive care unit is performed in 51.3%; 47.5%, 70.0% in minor, moderate and severe NASAH, respectively. Invasive BP monitoring is performed more often in severe NASAH (52.5%, 55.0%, 71.3% minor, moderate, severe). CV prophylaxis and transcranial doppler ultrasound (TCD) are performed in 41.3%, 45.0%, 63.8% in minor, moderate and severe NASAH, respectively. Indication for a second DSA is set in the majority of centers, whereas after two negative ones, a third DSA is less often indicated (2nd: 66.2%, 72.5%, 86.2%; 3rd: 3.8%, 3.8%, 13.8% minor, moderate, severe). This study confirms the influence of bleeding severity on treatment and follow-up of NASAH patients. Additionally, the existing inconsistency of treatment pathways throughout Germany is highlighted. Therefore, we suggest to conceive new treatment guidelines including this finding.

sPinal coRd stimulatiOn coMpared with lumbar InStrumEntation for low back pain after previous lumbar decompression (PROMISE): a prospective multicentre RCT.

INTRODUCTION: Persistent spine pain syndrome type 2 (PSPS2) represents a significant burden to the individual and society. Treatment options include revision surgery, stabilisation surgery of the spine, neuromodulation, analgesics and cognitive behavioural therapy. Nevertheless, structured treatment algorithms are missing as high-level evidence on the various treatments is sparse. The aim of this study is to compare higher frequency neuromodulation with instrumentation surgery in patients suffering from PSPS2. METHODS AND ANALYSIS: The sPinal coRd stimulatiOn coMpared with lumbar InStrumEntation for low back pain after previous lumbar decompression (PROMISE) trial is a prospective randomised rater blinded multicentre study. Patients suffering from PSPS2 with a functional burden of Oswestry Disability Index (ODI) >20 points are randomised to treatment via spinal cord stimulation or spinal instrumentation. Primary outcome is back-related functional outcome according to the ODI 12 months after treatment. Secondary outcomes include pain perception (visual analogue scale), Short Form-36, EuroQOL5D, the amount of analgesics, the length of periprocedural hospitalisation and adverse events. Follow-up visits are planned at 3 and 12 months after treatment. Patients with previous lumbar instrumentation, symptomatic spinal stenosis, radiographical apparent spinal instability or severe psychiatric or systemic comorbidities are excluded from the study. In order to detect a significant difference of ≥10 points (ODI) with a power of 80%, n=72 patients need to be included. The recruitment period will be 24 months with a subsequent 12 months follow-up. The beginning of enrolment is planned for October 2022. ETHICS AND DISSEMINATION: The PROMISE trial is the first randomised rater blinded multicentre study comparing the functional effectiveness of spinal instrumentation versus neuromodulation in patients with PSPS2 in order to achieve high-level evidence for these commonly used treatment options in this severely disabling condition. Patient recruitment will be performed at regular outpatient clinic visits. No further (print, social media) publicity is planned. The study is approved by the local ethics committee (LMU Munich, Germany) and will be conducted according to the Declaration of Helsinki. TRIAL REGISTRATION NUMBER: NCT05466110.

The transnasal endoscopic approach for resection of clival tumors: a single-center experience.

Clival tumors present challenging entities regarding their treatment options. Due to their proximity to critical neurovascular structures, the operative goal of gross total tumor resection is rendered more difficult by a high risk of neurological deficits. Retrospective cohort study of patients treated for clival neoplasms through a transnasal endoscopic approach between 2009 and 2020. Assessment of preoperative clinical status, length of operation, number of approaches, pre- and postoperative radiotherapy, and the clinical outcome. Presentation and clinical correlation with our new classification. In total, 59 transnasal endoscopic operations were performed on 42 patients over 12 years. Most lesions were clival chordomas; 63% of the lesions did not reach the brainstem. Cranial nerve impairment was present in 67% of the patients, and 75% of the patients with cranial nerve palsy improved after surgical treatment. Interrater reliability for our proposed tumor extension classification showed a substantial agreement (Cohen's κ = 0.766). The transnasal approach was sufficient to achieve a complete tumor resection in 74% of the patients. Clival tumors exhibit heterogeneous characteristics. Depending on clival tumor extension, the transnasal endoscopic approach can present a safe surgical technique for upper and middle clival tumor resection, with a low risk of perioperative complications and a high rate of postoperative improvement.

Hydrocephalus, cerebral vasospasm, and delayed cerebral ischemia following non-aneurysmatic spontaneous subarachnoid hemorrhages: an underestimated problem.

Non-aneurysmal subarachnoid hemorrhage (NASAH) is rare and mostly benign. However, complications such as cerebral vasospasm (CV), delayed cerebral ischemia (DCI), or post-hemorrhagic hydrocephalus (HC) may worsen the prognosis. The aim of this study was to evaluate the rate of these complications comparing perimesencephalic (PM) and non-perimesencephalic (NPM) SAH. Monocentric, retrospective analysis of patients diagnosed with NASAH from 01/2010 to 01/2021. Diagnosis was set only if vascular pathologies were excluded in at least one digital subtraction angiography, and NASAH was confirmed by cranial computed tomography (cCT) or lumbar puncture (LP). One hundred patients (62 female) with a mean age of 54.9 years (27-84) were identified. Seventy-three percent had a World Federation of Neurological Surgeons (WFNS) grading scale score I, while 9% were WFNS score IV or V at the time of admission. SAH was diagnosed by cCT in 86%, in 14% by lumbar puncture. Twenty-five percent necessitated short-term CSF diversion by extraventricular drainage or lumbar drainage, whereof 7 suffered from long-term HC treated with ventriculoperitoneal shunting (VPS). One patient without a short-term CSF drainage developed long-term HC. Ten percent developed CV, four of whom received intraarterial spasmolysis. Radiological DCI was diagnosed in 2%; none of these correlated with CV. Despite a mortality of 3% occurring solely in NPM SAH, the analyzed complication rate was comparable in both groups. We observed post-hemorrhagic complications in 35% of cases during the first 3 weeks after bleeding, predominantly in patients with NPM SAH. For this reason, close observation and cranial imaging within this time may be indicated not to overlook these complications.

Implementation of a three-dimensional (3D) robotic digital microscope (AEOS) in spinal procedures.

Three-dimensional exoscopes have been designed to overcome certain insufficiencies of operative microscopes. We aimed to explore the clinical use in various spinal surgeries. We performed surgery on patients with different spine entities in a neurosurgical department according to the current standard operating procedures over a 4-week period of time. The microsurgical part has been performed with Aesculap AEOS 3D microscope. Three neurosurgeons with different degree of surgical expertise completed a questionnaire with 43 items based on intraoperative handling and feasibility after the procedures. We collected and analyzed data from seventeen patients (35% male/65% female) with a median age of 70 years [CI 47-86] and median BMI of 25.8 kg/m2 [range 21-33]. We included a variety of spinal pathologies (10 degenerative, 4 tumor and 3 infectious cases) with different level of complexity. Regarding setup conflicts we observed issues with adjustment of the monitor position or while using additional equipment (e.g. fluoroscopy in fusion surgery) (p = 0.007/p = 0.001). However image resolution and sharpness as well as 3D-depth perception were completely satisfactory for all surgeons in all procedures. The utilization of the exoscopic arm was easy for 76.5% of the surgeons, and all of them declared a significant improvement of the surgical corridor. The 3D-exoscope implementation appears to achieve very satisfactory results in spinal procedures especially with minimally invasive approaches.

The Relation of Patient Expectations, Satisfaction, and Outcome in Surgery of the Cervical Spine: A Prospective Study.

STUDY DESIGN: We performed a prospective nonblinded single center observational study. OBJECTIVE: To investigate the relationship between expectations, outcome, and satisfaction with the outcome in patients undergoing cervical spine stabilization surgery. SUMMARY OF BACKGROUND DATA: In modern healthcare, patient-reported outcome measures and patient satisfaction have become an important aspect of quality control. Therefore, outcome benchmarks for specific diseases are highly desired. Numerous studies have investigated patient-reported outcome measures and what constitutes satisfaction in degenerative lumbar spine disease. In cervical spine surgery, it is less clear what drives the postoperative symptom burden and patient satisfaction and how this depends on the primary diagnosis and other patient factors. METHODS: This was a prospective, single center, observational study on patients undergoing cervical spine stabilization surgery for degenerative disease, trauma, infection, or tumor. Using the visual analogue scale for neck and arm pain, the neck disability index (NDI), the modified Japanese Orthopedic Association Score (mJOA) and patient-reported satisfaction, patient status and expectations before surgery, at discharge, 6 and 12 months after surgery were evaluated. RESULTS: One hundred five patients were included. Score-based outcome correlated well with satisfaction at 6 and 12 months. Except for low NDI expectations (≥15 points) that correlated with dissatisfaction, expectations in no other score were correlated with satisfaction. Expectations did influence the outcome in some subgroups and meeting expectations resulted in higher rates of satisfaction. Pain reduction plays an important role for satisfaction, independently from the predominant symptom or pathology. CONCLUSION: Satisfaction correlates well with outcome. Meeting expectations did influence satisfaction with the outcome. The NDI seems to be a valuable preoperative screening tool for poor satisfaction at 12 months. In degenerative pathology, pain is the predominant variable influencing satisfaction independently from the predominant symptom (including myelopathy). LEVEL OF EVIDENCE: 5.

Resection of supratentorial brain metastases with intraoperative radiotherapy. Is it safe? Analysis and experiences of a single center cohort.

Introduction: Intraoperative Radiotherapy (ioRT) is an emerging treatment option in oncologic surgery for various diseases including intraaxial brain lesions to improve surgical outcome and accelerate the adjuvant oncologic therapy. Despite its use in glioma surgery, the application and data regarding ioRT in the treatment of brain metastases (BMs) is sparse. Here were report the largest series of supratentorial BMs treated with resection and ioRT according to functional outcome and adverse events. Methods: We performed a retrospective chart review analysis of patients undergoing surgery for BMs following an interdisciplinary tumor board decision in every case with ioRT at our institution. Patient properties, functional status (Karnofsky Performance Score/KPS) before and after surgery as well as oncologic (disease, recursive partitioning analysis, lesion size) and operative parameters were analyzed until hospital discharge. Adverse events (AE) were recorded until 30 days after surgery and rated according to the Clavien Dindo Grading (CDG) scale. Results: 70 patients (40 female) with various oncologic diseases were identified and analyzed. Six underwent prior RT. Mean age was 66 ± 11 years. Preoperative median KPS was 80% with a mean BM volume of 3.2 ± 1.2 cm3. Nine patients (13%) experienced in total 14 AEs, including 2 cases (3%) of postoperative death (CDG5) and 2 with new postoperative epilepsy necessitating additional pharmacotreatment (CDG2). Five patients suffered from new neurologic deficit (CDG1) not needing further surgical or medical treatment. After surgery, the neurological status in 7 patients (10%) deteriorated while it improved in 21 cases (30%). Patients experiencing AEs had longer hospitalization and poorer postoperative KPS mdn. 90 vs. 80%. There was no statistically significant deterioration of the functional status during the immediate postoperative course in the whole patient cohort. Conclusion: Surgery for supratentorial BMs with ioRT seems safe and feasible. Further studies on the benefit regarding oncologic outcome need to be performed.

Surgical Treatment of Intraorbital Lesions.

BACKGROUND: Resection of pure intraorbital tumors is challenging owing to the nearness of the optic apparatus. The objective of this article was to report our experience with different intraorbital tumors and discuss classic approaches and obstacles. METHODS: A retrospective case series of patients who underwent surgery for intraorbital tumors at a tertiary neurosurgical center between June 2007 and January 2020 was performed. RESULTS: The study included 34 patients (median age 58 years; range, 18-87 years; 55.9% [19/34] female, 44.1% [15/34] male). Preoperative proptosis was observed in 67.6% (23/34); visual impairment, in 52.9% (18/34); diplopia, in 41.2% (14/34); and ptosis, in 38.3% (13/34). Intraconal tumors were found in 58.8% (20/34). The most common lesions were cavernous hemangiomas in 26.5% (9/34) and metastases in 14.7% (5/34). Gross total resection rate was 73.5% (25/34). Planned biopsy was performed in 14.7% (5/34). Median follow-up time was 15.5 months (interquartile range: 0-113 months). Surgical approaches included supraorbital approach (23.5% [8/34]), pterional approach (52.9% [18/34]), lateral orbitotomy (14.7% [5/34]), transnasal approach (5.9% [2/34]), and combined transnasal approach/lateral orbitotomy (2.9% [1/34]). Excluding planned biopsies, gross total resection was achieved in 80.0% (12/15) with pterional approach, 100% (7/7) with supraorbital approach, 80.0% (4/5) with lateral orbitotomy, and 100% (1/1) with transnasal approach/lateral orbitotomy. Complication rate requiring surgical intervention was 11.8% (4/34). CONCLUSIONS: Considering the low operative morbidity and satisfactory functional outcome, gross total resection of intraorbital lesions is feasible. We support use of classic transcranial and transorbital approaches. More invasive and complicated approaches were not needed in our series.

Intraoperative Neurophysiologic Assessment in Deep Brain Stimulation Surgery and its Impact on Lead Placement.

OBJECTIVES: While the efficacy of deep brain stimulation (DBS) to treat various neurological disorders is undisputed, the surgical methods differ widely and the importance of intraoperative microelectrode recording (MER) or macrostimulation (MS) remains controversially debated. The objective of this study is to evaluate the impact of MER and MS on intraoperative lead placement. PATIENTS AND METHODS: We included 101 patients who underwent awake bilateral implantation of electrodes in the subthalamic nucleus with MER and MS for Parkinson's disease from 2009 to 2017 in a retrospective observational study. We analyzed intraoperative motor outcomes between anatomically planned stimulation point (PSP) and definite stimulation point (DSP), lead adjustments and Unified Parkinson's Disease Rating Scale Item III (UPDRS-III), levodopa equivalent daily dose (LEDD), and adverse events (AE) after 6 months. RESULTS: We adjusted 65/202 leads in 47/101 patients. In adjusted leads, MS results improved significantly when comparing PSP and DSP (p < 0.001), resulting in a number needed to treat of 9.6. After DBS, UPDRS-III and LEDD improved significantly after 6 months in adjusted and nonadjusted patients (p < 0.001). In 87% of leads, the active contact at 6 months still covered the optimal stimulation point during surgery. In total, 15 AE occurred. CONCLUSION: MER and MS have a relevant impact on the intraoperative decision of final lead placement and prevent from a substantial rate of poor stimulation outcome. The optimal stimulation points during surgery and chronic stimulation strongly overlap. Follow-up UPDRS-III results, LEDD reductions, and DBS-related AE correspond well to previously published data.

How to avoid pneumocephalus in deep brain stimulation surgery? Analysis of potential risk factors in a series of 100 consecutive patients.

BACKGROUND: Accuracy of lead placement is the key to success in deep brain stimulation (DBS). Precise anatomic stereotactic planning usually is based on stable perioperative anatomy. Pneumocephalus due to intraoperative CSF loss is a common procedure-related phenomenon which could lead to brain shift and targeting inaccuracy. The aim of this study was to evaluate potential risk factors of pneumocephalus in DBS surgery. METHODS: We performed a retrospective single-center analysis in patients undergoing bilateral DBS. We quantified the amount of pneumocephalus by postoperative CT scans and corrected the data for accompanying brain atrophy by an MRI-based score. Automated computerized segmentation algorithms from a dedicated software were used. As potential risk factors, we evaluated the impact of trephination size, the number of electrode tracks, length of surgery, intraoperative blood pressure, and brain atrophy. RESULTS: We included 100 consecutive patients that underwent awake DBS with intraoperative neurophysiological testing. Systolic and mean arterial blood pressure showed a substantial impact with an inverse correlation, indicating that lower blood pressure is associated with higher volume of pneumocephalus. Furthermore, the length of surgery was clearly correlated to pneumocephalus. CONCLUSION: Our analysis identifies intraoperative systolic and mean arterial blood pressure as important risk factors for pneumocephalus in awake stereotactic surgery.

Intraventricular neuroepithelial tumors: surgical outcome, technical considerations and review of literature.

BACKGROUND: Intraventricular neuroepithelial tumors (IVT) are rare lesions and comprise different pathological entities such as ependymomas, subependymomas and central neurocytomas. The treatment of choice is neurosurgical resection, which can be challenging due to their intraventricular location. Different surgical approaches to the ventricles are described. Here we report a large series of IVTs, its postoperative outcome at a single tertiary center and discuss suitable surgical approaches. METHODS: We performed a retrospective chart review at a single tertiary neurosurgical center between 03/2009-05/2019. We included patients that underwent resection of an IVT emphasizing on surgical approach, extent of resection, clinical outcome and postoperative complications. RESULTS: Forty five IVTs were resected from 03/2009 to 05/2019, 13 ependymomas, 21 subependymomas, 10 central neurocytomas and one glioependymal cyst. Median age was 52,5 years with 55.6% (25) male and 44.4% (20) female patients. Gross total resection was achieved in 93.3% (42/45). 84.6% (11/13) of ependymomas, 100% (12/21) of subependymomas, 90% (9/10) of central neurocytomas and one glioependymal cyst were completely removed. Postoperative rate of new neurological deficits was 26.6% (12/45). Postoperative new permanent cranial nerve deficits occurred in one case with 4th ventricle subependymoma and one in 4th ventricle ependymoma. Postoperative KPSS was 90% (IR 80-100). 31.1% of the patients improved in KPSS, 48.9% remained unchanged and 20% declined. Postoperative adverse events rate was 20.0%. Surgery-related mortality was 2.2%. The rate of shunt/cisternostomy-dependent hydrocephalus was 13.3% (6/45). 15.4% of resected ependymomas underwent adjuvant radiotherapy. Mean follow-up was 26,9 (±30.1) months. CONCLUSION: Our surgical findings emphasize satisfactory complete resection throughout all entities. Surgical treatment can remain feasible, if institutional experience is given. Satisfying long-term survival and cure is possible by complete removal. Gross total resection should always be performed under function-remaining aspects due to mostly benign or slow growing nature of IVTs. Further data is needed to evaluate standard of care and alternative therapy options in rare cases of tumor recurrence or in case of patient collective not suitable for operative resection.

Midline Meningiomas of the Anterior Skull Base: Surgical Outcomes and a Decision-Making Algorithm for Classic Skull Base Approaches.

(1) Background: Midline meningiomas such as olfactory groove (OGMs), planum sphenoidale (PSMs), or tuberculum sellae meningiomas (TSMs) are challenging, and determining the appropriate approach is important. We propose a decision algorithm for choosing suitable transcranial approaches. (2) Methods: A retrospective chart review between 06/2007 and 01/2020. Clinical outcomes, radiographic findings, and postoperative complication rates were analyzed with respect to operative approaches. (3) Results: We included 88 patients in the analysis. Of these, 18.2% (16/88) underwent an interhemispheric approach, 72.7% (64/88) underwent a pterional/frontolateral/supraorbital approach, 2.3% (2/88) underwent a unilateral subfrontal approach, and 6.8% (6/88) underwent a bifrontal approach. All OGMs underwent median approaches, along with one PSM. All of the other PSMs and TSMs were resected via lateral approaches. The preoperative tumor volume was ∅20.2 ± 27.1 cm3. Median approaches had significantly higher tumor volume but also higher rates of Simpson I resection (75.0% vs. 34.4%). An improvement of visual deficits was observed in 34.1% (30/88). The adverse event rate was 17.0%. Median follow-up was 15.5 months (range 0-112 months). (4) Conclusions: Median approaches provides satisfying results for OGMs, lateral approaches enable sufficient exposure of the visual apparatus for PSMs and TSMs. In proposing a simple decision-making algorithm, the authors found that satisfactory outcomes can be achieved for midline meningiomas.

Early reduced dopaminergic tone mediated by D3 receptor and dopamine transporter in absence epileptogenesis.

OBJECTIVE: In Genetic Absence Epilepsy Rats From Strasbourg (GAERSs), epileptogenesis takes place during brain maturation and correlates with increased mRNA expression of D3 dopamine receptors (D3R). Whether these alterations are the consequence of seizure repetition or contribute to the development of epilepsy remains to be clarified. Here, we addressed the involvement of the dopaminergic system in epilepsy onset in GAERSs. METHODS: Experiments were performed using rats at different stages of brain maturation from three strains according to their increasing propensity to develop absence seizures: nonepileptic control rats (NECs), Wistar Hannover rats, and GAERSs. Changes in dopaminergic neurotransmission were investigated using different behavioral and neurochemical approaches: autoradiography of D3R and dopamine transporter, single photon emission computed tomographic imaging, acute and chronic drug effects on seizure recordings (dopaminergic agonists and antagonists), quinpirole-induced yawns and dopamine synaptosomal uptake, microdialysis, brain tissue monoamines, and brain-derived neurotrophic factor quantification. RESULTS: Autoradiography revealed an increased expression of D3R in 14-day-old GAERSs, before absence seizure onset, that persists in adulthood, as compared to age-matched NECs. This was confirmed by increased yawns, a marker of D3R activity, and increased seizures when animals were injected with quinpirole at low doses to activate D3R. We also observed a concomitant increase in the expression and activity of the dopamine transporter in GAERSs before seizure onset, consistent with both lowered dopamine basal level and increased phasic responses. SIGNIFICANCE: Our data show that the dopaminergic system is persistently altered in GAERSs, which may contribute not only to behavioral comorbidities but also as an etiopathogenic factor in the development of epilepsy. The data suggest that an imbalanced dopaminergic tone may contribute to absence epilepsy development and seizure onset, as its reversion by a chronic treatment with a dopamine stabilizer significantly suppressed epileptogenesis. Our data suggest a potential new target for antiepileptic therapies and/or improvement of quality of life of epileptic patients.

Introduction of a self-holding retractor for optimized abdominal visualization in ventriculoperitoneal shunt surgery: first experiences at a single center.

OBJECTIVE: Ventriculoperitoneal shunt implantation is a common procedure in general neurosurgery. The patient population is often fragile, ranging from elderly to pediatric patients, and avoidance of perioperative complication is of utmost importance. Abdominal catheter dislocation has been found to be a common cause for early shunt dysfunction and needs to be avoided by optimal visualization of the abdominal catheter insertion zone. Here, we introduce a self-holding wound retractor system Alexis® and demonstrate its use for abdominal shunt surgery in a series of patients. METHODS: We explain the use of the Alexis® self-holding wound retractor during open ventriculoperitoneal shunt surgery in a series of 16 patients operated at our institution. RESULTS: The self-holding retractor consists of two polymer rings connected by a polymer membrane. The deep ring is easily placed on the internal fascia of the straight muscle and circular retraction is achieved by twisting the upper ring. Free hand working can then be performed by a single surgeon with good abdominal exposure. No case of abdominal dislocation or infection occurred in our series, although no properly powered statistical analysis can be performed regarding the sample size. CONCLUSION: We demonstrate the Alexis® Wound Retractor, which is an easy tool for optimal visualization of the abdominal catheter insertion zone. We believe it can facilitate surgical practice of shunt surgery, especially in obese patients.

Incidence, depth, and severity of surgical site infections after neurosurgical interventions.

BACKGROUND: Today, there are only few reports on the incidence of surgical site infections (SSIs) in neurosurgery. The objective of this work was to determine the rate of SSI at a tertiary neurosurgical department for benchmarking purpose. METHODS: Data of consecutive patients undergoing neurosurgical treatment between January 2013 and December 2016 were prospectively entered into a registry. SSIs were diagnosed according to the 2017 Centers for Disease Control and Prevention criteria, with severity graded according to the Clavien-Dindo grade (CDG). We analyzed type and length of surgery (LOS), time to SSI, responsible microorganisms, and its association with the functional status (Karnofsky Performance Status = KPS). RESULTS: Of n = 5463 procedures, a SSI occurred in n = 106 (1.94%). The highest rates of SSI occurred after vascular (3.4%) and cerebrospinal fluid (CSF) diversion procedures (3%), as well as after procedures performed to treat a previous complication (2.9%). There was no difference in LOS across procedures with and without SSI. The median time between the index procedure and SSI was 15.5 days. SSIs were most frequently diagnosed after hospital discharge (55%). The most common microorganisms were coagulase-negative staphylococci, Staphylococcus aureus, and Escherichia coli. In 62.3% of cases, SSI required invasive treatment (surgical revision). Patients with SSI in the in- and out-patient setting (SSI occurring after hospital discharge) presented both with a median KPS of 80. CONCLUSIONS: The current report provides an overview on SSI in a contemporary, unselected, large series of patients undergoing modern neurosurgical care for benchmarking purposes. The overall rate of SSI was about 2%, but subpopulations with higher risks were identified where additional measures could be taken to prevent SSI and monitor patients at risk more closely for SSI.

Long-term Outcome for Open and Endoscopically Resected Sinonasal Tumors.

OBJECTIVE: Endoscopic resection of sinonasal cancer has become an alternative to open craniofacial surgery and leads to safe and satisfying results in emerging numbers. Randomized study data comparing outcomes between approaches are missing. Hence, it remains unclear which subgroups of patients might profit most from each technique. We aimed to identify such patient and tumor characteristics and gather information for future prospective study design. STUDY DESIGN: Case series with chart review. SETTING: Tertiary academic center. SUBJECTS AND METHODS: This study is based on a retrospective chart review of 225 patients undergoing open craniofacial or endoscopic resection for sinonasal malignancy between 1993 and 2015 at Munich University Hospital. Statistical analyses include t test, chi-square, Kaplan-Meier charts, and univariate and multivariate analyses. RESULTS: The sample size was similar between the endoscopic and open surgery groups. Tumors were significantly larger in patients who underwent open craniofacial resection. The risk of notable bleeding ( P = .041) was lower and hospital stay shorter ( P = .001) for endoscopic interventions of all tumor stages. Rates of overall ( P = .024) and disease-specific ( P = .036) survival were significantly improved for endoscopic cases; improved recurrence-free survival rates did not achieve statistical significance ( P = .357). For cases matched for tumor size, this improvement was confirmed for T3 tumors ( P = .038). Regional and distant metastatic tumor spread generally worsened survival in both surgical subgroups. Multivariate Cox regression analysis revealed independent prognosticators for overall survival. CONCLUSION: Endoscopic tumor resection remains a suitable option for distinct indications and showed improved outcome in intermediate-stage tumors in our collective. Further randomized studies acknowledging the here-identified factors are needed to improve future therapy guidelines and patient care.

Better Hemodynamics and Less Antihypertensive Medication: Comparison of Scalp Block and Local Infiltration Anesthesia for Skull-Pin Placement in Awake Deep Brain Stimulation Surgery.

OBJECTIVE: In deep brain stimulation (DBS) surgery, acute high blood pressure (BP) is a risk factor for intracranial hemorrhage. To minimize pain and hypertensive conditions, sufficient local anesthesia is mandatory. We evaluated whether local instillation of anesthetics (LA) or a scalp block (SB) is superior concerning intraoperative hemodynamics and analgesia. METHODS: We retrospectively analyzed intraoperative cardiovascular parameters and perioperative medication in 47 patients (LA = 29, SB = 18) undergoing DBS surgery. Primary study end points were intraoperative systolic BP and heart rate. Secondary end points were use of intraoperative antihypertensives and perioperative analgesics. RESULTS: Patients who had SB showed lower mean systolic BP and heart rate compared with patients who had LA. Patients who had LA required more antihypertensive medication to stabilize BP. BP was higher, particularly during the first 90 minutes of surgery, in patients who had LA. Thereafter, more antihypertensives were necessary to achieve sufficient BP control in the LA group. The dose of analgesics did not differ significantly between both groups during and after surgery. CONCLUSIONS: Our data suggest that SB might be superior to LA for DBS surgery with respect to BP control and hemodynamics. The need for analgesics does not differ substantially between both anesthetic treatment options.