Association of Fluid Balance and Hemoglobin Decline With Neurological Outcome After Aneurysmal Subarachnoid Hemorrhage.

OBJECTIVES: To explore the relationship between fluid balance and hemoglobin decline with secondary infarctions and neurologic outcome in aneurysmal subarachnoid hemorrhage (aSAH) patients. DESIGN: Secondary analysis of the Earlydrain trial, a prospective randomized controlled study investigating prophylactic lumbar drain use in aSAH patients. SETTING: Patients with aSAH treated in ICUs at 19 tertiary hospitals in Germany, Switzerland, and Canada. PATIENTS: From January 2011 to January 2016, 287 patients were enrolled in the Earlydrain trial. Only files with complete information on both daily hemoglobin and balance values were used, leaving 237 patients for analysis. INTERVENTIONS: Investigation of fluid balance management and hemoglobin levels during the initial 8 days post-aSAH to establish thresholds for unfavorable outcomes and assess their impact on secondary infarctions and 6-month neurologic outcome on the modified Rankin Scale (mRS). MEASUREMENTS AND MAIN RESULTS: Patients with unfavorable outcome after 6 months (mRS > 2) showed greater hemoglobin decline and increased cumulative fluid balance. A significant inverse relationship existed between fluid balance and hemoglobin decline. Thresholds for unfavorable outcome were 10.4 g/dL hemoglobin and 4894 mL cumulative fluid balance in the first 8 days. In multivariable analysis, fluid balance, but not fluid intake, remained significantly associated with unfavorable outcome, while the influence of hemoglobin lessened. Fluid balance but not hemoglobin related to secondary infarctions, with the effect being significant after inverse probability of treatment weighting. Transfusion was associated with unfavorable outcomes. CONCLUSIONS: Increased fluid balance influences hemoglobin decline through hemodilution. Fluid overload, rather than a slight decrease in hemoglobin levels, appears to be the primary factor contributing to poor outcomes in aSAH patients. The results suggest aiming for euvolemia and that a modest hemoglobin decline may be tolerated. It may be advisable to adopt a restrictive approach to transfusions, as they can potentially have a negative effect on outcome.

Predictive role of intracranial PD-L1 expression in a real-world cohort of NSCLC patients treated with immune checkpoint inhibition following brain metastasis resection.

BACKGROUND: Emerging evidence suggests that treatment of NSCLC brain metastases with immune checkpoint inhibitors (ICIs) is associated with response rates similar to those of extracranial disease. Programmed death-ligand 1 (PD-L1) tumor proportion score (TPS) serves as a predictive biomarker for ICI response. However, the predictive value of brain metastasis-specific (intracranial) PD-L1 TPS is not established. We investigated the role of intra- and extracranial PD-L1 TPS in NSCLC patients treated with ICI following brain metastasis resection. METHODS: Clinical data from NSCLC patients treated with ICI following brain metastasis resection (n = 64) were analyzed. PD-L1 TPS of brain metastases (n = 64) and available matched extracranial tumor tissue (n = 44) were assessed via immunohistochemistry. Statistical analyses included cut point estimation via maximally selected rank statistics, Kaplan-Meier estimates, and multivariable Cox regression analysis for intracranial progression-free survival (icPFS), extracranial progression-free survival (ecPFS), and overall survival (OS). RESULTS: PD-L1 expression was found in 54.7% of brain metastases and 68.2% of extracranial tumor tissues, with a median intra- and extracranial PD-L1 TPS of 7.5% (0 - 50%, IQR) and 15.0% (0 - 80%, IQR), respectively. In matched tissue samples, extracranial PD-L1 TPS was significantly higher than intracranial PD-L1 TPS (p = 0.013). Optimal cut points for intracranial and extracranial PD-L1 TPS varied according to outcome parameter assessed. Notably, patients with a high intracranial PD-L1 TPS (> 40%) exhibited significantly longer icPFS as compared to patients with a low intracranial PD-L1 TPS (≤ 40%). The cut point of 40% for intracranial PD-L1 TPS was independently associated with OS, icPFS and ecPFS in multivariable analyses. CONCLUSION: Our study highlights the potential role of intracranial PD-L1 TPS in NSCLC, which could be used to predict ICI response in cases where extracranial tissue is not available for PD-L1 assessment as well as to specifically predict intracranial response.

Analysis of Cerebral Spinal Fluid Drainage and Intracranial Pressure Peaks in Patients with Subarachnoid Hemorrhage.

BACKGROUND: After aneurysmal subarachnoid hemorrhage (aSAH), elevated intracranial pressure (ICP) due to disrupted cerebrospinal fluid (CSF) dynamics is a critical concern. An external ventricular drainage (EVD) is commonly employed for management; however, optimal strategies remain debated. The randomized controlled Earlydrain trial showed that an additional prophylactic lumbar drainage (LD) after aneurysm treatment improves neurological outcome. We performed a post hoc investigation on the impact of drainage volumes and critical ICP values on patient outcomes after aSAH. METHODS: Using raw patient data from Earlydrain, we analyzed CSF drainage amounts and ICP measurements in the first 8 days after aSAH. Outcomes were the occurrence of secondary infarctions and the score on the modified Rankin scale after 6 months, dichotomized in values of 0-2 as favorable and 3-6 as unfavorable. Repeated measurements were considered with generalized estimation equations. RESULTS: Earlydrain recruited 287 patients, of whom 221 received an EVD and 140 received an LD. Higher EVD volumes showed a trend to more secondary infarctions (p = 0.09), whereas higher LD volumes were associated with less secondary infarctions (p = 0.009). The mean total CSF drainage was 1052 ± 659 mL and did not differ concerning infarction and neurological outcome. Maximum ICP values were higher in patients with poor outcomes but not related to drainage volumes via EVD. After adjustment for aSAH severity and total CSF drainage, higher LD volume was linked to favorable outcome (per 100 mL: odds ratio 0.61 (95% confidence interval 0.39-0.95), p = 0.03), whereas higher EVD amounts were associated with unfavorable outcome (per 100 mL: odds ratio 1.63 (95% confidence interval 1.05-2.54), p = 0.03). CONCLUSIONS: Findings indicate that effects of CSF drainage via EVD and LD differ. Higher amounts and higher proportions of LD volumes were associated with better outcomes, suggesting a potential quantity-dependent protective effect. Optimizing LD volume and mitigating ICP spikes may be a strategy to improve patient outcomes after aSAH. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01258257.

Enhancing the prediction for shunt-dependent hydrocephalus after aneurysmal subarachnoid hemorrhage using a machine learning approach.

Early and reliable prediction of shunt-dependent hydrocephalus (SDHC) after aneurysmal subarachnoid hemorrhage (aSAH) may decrease the duration of in-hospital stay and reduce the risk of catheter-associated meningitis. Machine learning (ML) may improve predictions of SDHC in comparison to traditional non-ML methods. ML models were trained for CHESS and SDASH and two combined individual feature sets with clinical, radiographic, and laboratory variables. Seven different algorithms were used including three types of generalized linear models (GLM) as well as a tree boosting (CatBoost) algorithm, a Naive Bayes (NB) classifier, and a multilayer perceptron (MLP) artificial neural net. The discrimination of the area under the curve (AUC) was classified (0.7 ≤ AUC < 0.8, acceptable; 0.8 ≤ AUC < 0.9, excellent; AUC ≥ 0.9, outstanding). Of the 292 patients included with aSAH, 28.8% (n = 84) developed SDHC. Non-ML-based prediction of SDHC produced an acceptable performance with AUC values of 0.77 (CHESS) and 0.78 (SDASH). Using combined feature sets with more complex variables included than those incorporated in the scores, the ML models NB and MLP reached excellent performances, with an AUC of 0.80, respectively. After adding the amount of CSF drained within the first 14 days as a late feature to ML-based prediction, excellent performances were reached in the MLP (AUC 0.81), NB (AUC 0.80), and tree boosting model (AUC 0.81). ML models may enable clinicians to reliably predict the risk of SDHC after aSAH based exclusively on admission data. Future ML models may help optimize the management of SDHC in aSAH by avoiding delays in clinical decision-making.

Decompression with or without fusion in degenerative adjacent segment stenosis after lumbar fusions.

Adjacent segment stenosis can occur after lumbar fusion surgery, leading to significant discomfort and pain. If further surgeries are required, the choice of the operative technique is an individual decision. In patients without over instability, it is still uncertain whether patients with adjacent spinal stenosis should be treated like primary lumbar spinal stenosis via decompressive surgery alone or with decompression and fusion. This is a retrospective analysis with prospective collected data. We included patients with adjacent segment stenosis after lumbar fusion. Patients with spinal deformity and/or obvious instability and/or significant neuroforaminal stenosis were excluded. All patients were divided into two groups according to the surgical technique that has been used: (a) treated via microsurgical decompression (MDG), (b) decompression and fusion of the adjacent segment (FG). Treatment decision was at discretion of the surgeon. Primary outcome was the need for further lumbar surgery after 1 year. In addition, patient reported outcome was measured via numerical rating scale (NRS), SF-36, Oswestry disability Index (ODI), Pittsburgh Sleep Quality Index (PSQI), and General Depression Scale before and after 1 year after surgery. In a further follow-up, need for additional lumbar surgery was redetermined. Total study population was 37 patients with a median age of 72 years. A total of 86.1% of patients suffered from a proximal adjacent segment stenosis and most common level was L3/4 (51.4%). A total of 61.1% of included patients developed adjacent segment stenosis after fusion of one single lumbar segment. Eighteen patients were included in MDG and 19 patients in FG. Both groups benefited from surgical interventions and there was no significant difference concerning pain, pain associated disability, sleeping, life quality, and mood after 1 year or the need of follow-up surgeries 1 year after primary fusion (5 in MDG vs. 5 in FG, p = 0.92) and at the second follow-up with a median time after surgery of 30 months (6 in MDG vs. 7 in FG, p = 0.823). Duration of surgery and hospital stay was significant shorter in MDG. There was no difference concerning operative complications rate. Both groups improved significantly in pain associated disability index, pain in motion, and concerning the sleeping quality. The present study indicates that decompression may not be inferior to decompression and fusion in patients suffering from degenerative adjacent segment stenosis without obvious signs of instability, deformation, and neuroforaminal stenosis after lumbar fusion in short-term follow-up. Due to significant shorter time of surgery, a pure microsurgical decompression may be a sufficient alternative to a decompression and fusion, particular regarding old age of this patient cohort.

Bedside Technique for the Implantation of Licox Brain Tissue Oxygen Probes in Occipital Regions: A Technical Note.

BACKGROUND: Continuous bedside monitoring of brain tissue oxygen levels is a crucial component in the management of comatose patients suffering from acute brain injury on neurointensive care units. Ensuring sufficient brain oxygenation is recognized as an essential objective within neurocritical care, aimed at safeguarding patients from secondary ischemia. Hypoperfusion in occipital and the posterior watershed regions often remains undetected, as the placement of probes in these areas is challenging. A major concern is that patients would have to lie on the traditionally used implanted bolts due to the occipital entry point of the probes. Therefore, we present a novel technique compatible with magnetic resonance imaging that enables bedside placement of brain tissue oxygen probes without the use of a bolt in these areas. METHODS: We conducted bedside implantations of Licox brain tissue oxygenation probes through Frazier's point utilizing peripheral venous cannulas on burr holes eliminating the need for bolts. RESULTS: A novel approach was successfully established for the bedside implantation of a Licox brain tissue oxygenation probe for occipital regions. CONCLUSIONS: This technical note describes the feasibility of a novel, simple, and straightforward bedside technique for boltless implantation of Licox brain tissue oxygen probes leading to rigid fixation and compatibility with magnetic resonance imaging.

Early Complications and Outcome After Treatment of Ruptured Aneurysms in Patients with Subarachnoid Hemorrhage-A Post Hoc Analysis of the EARLYDRAIN Trial.

OBJECTIVE: Aneurysmal subarachnoid hemorrhage (aSAH) from a ruptured intracranial aneurysm is a severe, life-threatening condition, with high morbidity and mortality. The current treatment often involves surgical clipping or endovascular treatment within the first 24-48 hours. Although there is ample evidence of complications in treating unruptured aneurysms, similar data in patients with acutely ruptured aneurysms are limited. The recently completed EARLYDRAIN trial showed improved neurologic results from lumbar drainage after aneurysm treatment in patients with aSAH. Using this data set, we aim to study the frequency and effects of complications and identify associated risk factors. METHODS: A substudy was carried out of the prospective multicenter randomized controlled EARLYDRAIN trial. We analyzed treatment-associated complications (bleeding and/or infarctions) detected on computed tomography on day 1 after aneurysm occlusion. Outcomes were the occurrence of postprocedural complications, secondary infarctions in the acute phase, and the modified Rankin Scale score after 6 months. RESULTS: The EARLYDRAIN trial recruited 287 patients in 19 centers. Of these patients, 56 (19.5%) experienced a treatment complication. Twenty-five patients (8.7%) experienced postprocedural intracranial hemorrhage and 34 patients (11.8%) experienced a treatment-associated infarction. Patients with a complication showed more secondary infarctions (P = 0.049) and worse neurologic outcomes after 180 days (P = 0.025) compared with patients with no complication. Aneurysm location, rebleeding before the treatment, number of patients recruited per center, and the day of the treatment were independent risk factors for the occurrence of complications. CONCLUSIONS: The present study shows that patients with aSAH frequently experience intervention-associated complications associated with aneurysm occlusion required to prevent recurrent hemorrhage. Consequently, patients with aSAH with treatment-related complications more often experience a worse clinical course and poor outcome.

Robotic stereotactic radiosurgery for intracranial meningiomas in elderly patients: assessment of treatment efficacy and safety.

Purpose: Stereotactic radiosurgery (SRS) has been increasingly used to treat intracranial pathologies in elderly patients. The treatment efficiency of SRS has been demonstrated in meningiomas, with excellent local control. We aimed to analyze the safety of robotic SRS in elderly patients with meningiomas. Methods: We searched for patients with suspected WHO °I meningioma ≥ 60 years old, who underwent CyberKnife (CK) SRS from January 2011 to December 2021. Tumor localization was categorized using the "CLASS" algorithmic scale. Tumor response was evaluated using the Response Assessment in Neuro-Oncology (RANO) criteria for meningiomas. Adverse effects were graded using the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0 and a cox regression was performed to investigate possible predictors. Results: We identified 82 patients with 102 CK-treated lesions that matched the criteria for the first SRS. The median age was 70 [IQR 64-75] years, and 24.3% of the patients were aged > 75 years. Multiple lesions (up to six) were treated in 14.1% of the SRS-sessions. A previous surgery was performed in 57.3% of lesions, with a median time interval of 41 [IQR 10 - 58] months between the initial surgical procedure and the SRS treatment. In 47.9% of cases, CLASS 3 meningiomas at high-risk locations were irradiated. Single fraction radiosurgery was applied to 62.5% of the lesions, while in the remaining cases multi-session SRS with three to five fractions was used. During the median follow-up period of 15.9 months, lesion size progression was observed in 3 cases. Karnofsky Performance Status (KPS) declined by ≥ 20 points in four patients. Adverse effects occurred in 13 patients, while only four patients had CTCAE ≥2 toxicities. Hereby only one of these toxicities was persistent. The occurrence of complications was independent of age, planned target volume (PTV), high-risk localization, and surgery before SRS. Conclusion: The data indicates that SRS is a safe, efficient, and convenient treatment modality for elderly patients with meningioma, even at high-risk locations.

Influence of the sagittal spinal profile type on the long-term outcome of patients with symptomatic lumbar spinal stenosis after microsurgical decompression.

OBJECTIVE: Microsurgical decompression for patients with symptomatic lumbar spinal stenosis (LSS) has demonstrated long-term improvement concerning pain and function. Nonetheless, a considerable proportion of these patients do not experience satisfactory alleviation of symptoms. Previous studies have not found a direct influence of single sagittal parameters on patient outcomes. However, recent research indicates that a composite of parameters, presented in specific sagittal profile types (SPTs) that were defined by Roussouly and colleagues, may affect these outcomes. This study aims to investigate the impact of SPT on long-term outcomes of patients with LSS following microsurgical decompression. METHODS: This study is a prospective clinical observation. Patients with symptomatic LSS, who underwent microsurgical treatment and had long-term follow-up data for at least 36 months, were included. Patients with spinal deformity, fractures, or significant instability were excluded. Outcomes were measured using the numeric rating scale for pain, 36-Item Short Form Health Survey for quality of life, walking distance, Oswestry Disability Index, Roland-Morris Disability Questionnaire, and Odom's criteria. SPT was determined in blinded fashion by using preoperative long standing radiographs. RESULTS: The initial population of this observational study consisted of 128 patients, with long-term results available for 87 individuals, including 24 patients with SPT1, 20 with SPT2, 27 with SPT3, and 16 with SPT4. The average age was 70 years, with a slight male majority (56.3%) and a mean BMI of 27.9 kg/m2. After a median follow-up of 48 months, all groups showed significant improvement in walking distance, leg pain, and disability. Overall, 75% reported satisfaction with the surgery. However, patients with SPT1, which is characterized by low sacral slope and specific spinal curvatures, experienced significantly less improvement in back pain (p = 0.018) and related disability (p = 0.030), and lower satisfaction compared to other SPT groups (p = 0.008). CONCLUSIONS: The sagittal spinal type is influencing the long-term outcome of patients suffering from symptomatic LSS. Patients with a combination of a flat sacral slope and a low overall lumbar lordosis with a high lordosis in the lower lumbar spine (i.e., spinal SPT1) showed worse outcome concerning back pain and had decreased satisfaction with surgery than comparable subjects from other SPT groups. Consequently, the authors recommend the assessment of sagittal spinal types in patients diagnosed with symptomatic spinal stenosis prior to decompression surgery. Inclusion of SPT in the preoperative consultation process can provide valuable insights, potentially guiding practitioners to more tailored patient counseling.

Augmented 360° Three-Dimensional Virtual Reality for Enhanced Student Training and Education in Neurosurgery.

OBJECTIVE: This prospective study assesses the acceptance and usefulness of augmented 360° virtual reality (VR) videos for early student education and preparation in the field of neurosurgery. METHODS: Thirty-five third-year medical students participated. Augmented 360° VR videos depicting three neurosurgical procedures (lumbar discectomy, brain metastasis resection, clipping of an aneurysm) were presented during elective seminars. Multiple questionnaires were employed to evaluate conceptual and technical aspects of the videos. The analysis utilized ordinal logistic regression to identify crucial factors contributing to the learning experience of the videos. RESULTS: The videos were consistently rated as good to very good in quality, providing detailed demonstrations of intraoperative anatomy and surgical workflow. Students found the videos highly useful for their learning and preparation for surgical placements, and they strongly supported the establishment of a VR lounge for additional self-directed learning. Notably, 81% reported an increased interest in neurosurgery, and 47% acknowledged the potential influence of the videos on their future choice of specialization. Factors associated with a positive impact on students' interest and learning experience included high technical quality and comprehensive explanations of the surgical steps. CONCLUSIONS: This study demonstrated the high acceptance of augmented 360° VR videos as a valuable tool for early student education in neurosurgery. While hands-on training remains indispensable, these videos promote conceptual knowledge, ignite interest in neurosurgery, and provide a much-needed orientation within the operating room. The incorporation of detailed explanations throughout the surgeries with augmentation using superimposed elements, offers distinct advantages over simply observing live surgeries.

Study protocol for a prospective, randomized, multicenter trial to investigate the influence of peripheral nerve stimulation on patients with chronic sacroiliac joint syndrome (SILENCING).

BACKGROUND: The prevalence of sacroiliac joint pain (SIJP) is estimated to be 10-30% in patients with chronic low back pain. Numerous conservative and surgical treatment modalities for SIJP have been described with limited evidence regarding long-term pain relief. Spinal cord stimulation (SCS) is a well-established technique to treat patients with chronic low back pain. However, the effect on patients with SIJP is not consistent. Therefore, peripheral nerve stimulation (PNS) for chronic SIJP was implemented in experimental trials. Clinical data on PNS for SIJP is still lacking. The authors present a case series and a protocol for a prospective, multicenter study to determine the effect of PNS in patients with chronic intractable SIJP. METHOD: A multicenter, prospective randomized controlled trial was designed. Patients with chronic intractable SIJP will be recruited and randomized in a 4:3 ratio to either the peripheral nerve stimulation group or to the best medical treatment group. A total of 90 patients are planned to be enrolled (52 in the PNS group and 38 in the BMT group). Patients in the intervention group receive a percutaneous implantation of a unilateral or bilateral lead which is externalized for a trial phase for 3-14 days. After trial phase only patients with at least 50% reduction of pain receive an impulse generator for permanent stimulation. Regular visits for participants are planned on day 0, after 3 months (± 30 days), 6 months (± 30 days), and 12 months (± 60 days). The primary outcome measurements is the difference in Numeric Pain Rating Scale (NRS) between baseline and after 6 months. Secondary outcomes is improvement of pain associated disability (ODI) and improvement of health-related quality of life after 6 and 12 months. DISCUSSION: We have described the protocol for a prospective, multicenter, randomized trial evaluating the influence of PNS on patients with chronic sacroiliac joint syndrome. We believe that PNS on patients with chronic sacroiliac joint syndrome will show promising results regarding pain relief and quality of life in comparison to BMT after 12 months. The design of this trial promises high evidence in comparison to the data to date. TRIAL REGISTRATION: ClinicalTrials.gov, NCT05357300. Registered on April 26, 2022.

Preoperatively-determined Red Distribution Width (RDW) predicts prolonged length of stay after single-level spinal fusion in elderly patients.

Introduction: Elderly patients receiving lumbar fusion surgeries present with a higher risk profile, which necessitates a robust predictor of postoperative outcomes. The Red Distribution Width (RDW) is a preoperative routinely determined parameter that reflects the degree of heterogeneity of red blood cells. Thereby, RDW is associated with frailty in hospital-admitted patients. Research question: This study aims to elucidate the potential of RDW as a frailty biomarker predictive of prolonged hospital stays following elective mono-segmental fusion surgery in elderly patients. Material and methods: In this retrospective study, we included all patients with age over 75 years that were treated via lumbar single-level spinal fusion from 2015 to 2022 at our tertiary medical center. Prolonged length of stay (pLOS) was defined as a length ≥ the 3rd quartile of LOS of all included patients. Classical correlation analysis, Receiver-operating characteristic (ROC) and new machine learning algorithms) were used. Results: A total of 208 patients were included in the present study. The median age was 77 (IQR 75-80) years. The median LOS of the patients was 6 (IQR 5-8) days. The data shows a significant positive correlation between RDW and LOS. RDW is significantly enhanced in the pLOS group. New machine learning approaches with the imputation of multiple variables can enhance the performance to an AUC of 71%. Discussion and conclusion: RDW may serve as a predictor for a pLOS in elderly. These results are compelling because the determination of this frailty biomarker is routinely performed at hospital admission. An improved prognostication of LOS could enable healthcare systems to distribute constrained hospital resources efficiently, fostering evidence-based decision-making processes.

Oscillation analysis as a supporting element toward safe and reliable lumbar catheter intracranial pressure monitoring.

OBJECTIVE: Lumbar drainage of cerebrospinal fluid for treatment of refractory increased intracranial pressure (ICP) is associated with the risk of infratentorial herniation, but real-time biomarkers for signaling herniation at bedside are lacking. Here, the authors tested whether an alteration of pulsatile waveform conduction across the level of the foramen magnum could serve as an indicator of insufficient hydrostatic communication and impending herniation. METHODS: This prospective observational cohort study included patients with severe acute brain injury who underwent continuous external ventricular drain monitoring of ICP and lumbar drain pressure monitoring. Continuous recordings of ICP, lumbar pressure (LP), and arterial blood pressure (ABP) were screened throughout a recording period of 4-10 days. Pressure differences between ICP and LP > 5 mm Hg for 5 minutes were defined as a Δ-event, implicating nonsufficient hydrostatic communication. During this period, oscillation analysis of the ICP, LP, and ABP waveforms was performed by determining the eigenfrequencies (EFs) and their amplitudes (AEF) via Fourier transformation scripted in Python. RESULTS: Of 142 patients, 14 exhibited a Δ-event, with a median (range) ICP of 12.2 (10.7-18.8) mm Hg and LP of 5.6 (3.3-9.8) mm Hg during 2993 hours of recording time. The AEF ratio between ICP and LP (p < 0.01) and between ABP and LP (p = 0.032) increased significantly during Δ-events compared with the baseline values determined 3 hours prior to the event. The ratio between ICP and ABP remained unaffected. CONCLUSIONS: Oscillation behavior analysis of LP and ABP waveforms during controlled lumbar drainage may serve as a personalized, simple, and effective biomarker to signal impending infratentorial herniation in real time without the need for simultaneous ICP monitoring.

Outcome and management of decompressive hemicraniectomy in malignant hemispheric stroke following cardiothoracic surgery.

Management of malignant hemispheric stroke (MHS) after cardiothoracic surgery (CTS) remains difficult as decision-making needs to consider severe cardiovascular comorbidities and complex coagulation management. The results of previous randomized controlled trials on decompressive surgery for MHS cannot be generally translated to this patient population and the expected outcome might be substantially worse. Here, we analyzed mortality and functional outcome in patients undergoing decompressive hemicraniectomy (DC) for MHS following CTS and assessed the impact of perioperative coagulation management on postoperative hemorrhagic and cardiovascular complications. All patients that underwent DC for MHS resulting as a complication of CTS between June 2012 and November 2021 were included in this observational cohort study. Outcome was determined according to the modified Rankin Scale (mRS) score at 1 and 3-6 months. Clinical and demographic data, anticoagulation management and postoperative hemorrhagic and thromboembolic complications were assessed. In order to evaluate a predictive association between clinical and radiological parameters and the outcome, we used a multivariate logistic regression analysis. Twenty-nine patients undergoing DC for MHS after CTS with a female-to-male ratio of 1:1.9 and a median age of 60 (IQR 49-64) years were identified out of 123 patients undergoing DC for MHS. Twenty-four patients (83%) received pre- or intraoperative substitution. At 30 days, the in-hospital mortality rate and neurological outcome corresponded to 31% and a median mRS of 5 (5-6), which remained stable at 3-6 months [Mortality: 42%, median mRS: 5 (4-6)]. Postoperatively, 15/29 patients (52%) experienced new hemorrhagic lesions and Bayesian logistic regression predicting mortality (mRS = 6) after imputing missing data demonstrated a significantly increased risk for mortality with longer aPPT (OR = 13.94, p = .038) and new or progressive hemorrhagic lesions after DC (OR = 3.03, p = .19). Notably, all but one hemorrhagic lesion occurred before discontinued anticoagulation and/or platelet inhibition was re-initiated. Despite perioperative discontinuation of anticoagulation and/or platelet inhibition, no coagulation-associated cardiovascular complications were noted. In conclusion, Cardiothoracic surgery patients suffering MHS will likely experience severe neurological disability after DC, which should remain a central aspect during counselling and decision-making. The complex coagulation situation after CTS, however, should not per se rule out the option of performing life-saving surgical decompression.

Peripheral nerve stimulation for the treatment of chronic knee pain.

The average age of our population is increasing, resulting in a high incidence of chronic degenerative knee pathologies. Several treatment options, including surgical procedures are available to help mitigate these pathologies. However, the percentage of subjects with chronic post-surgical knee pain is still estimated at 16-20%. Neuromodulation techniques such as spinal cord stimulation and dorsal root ganglion stimulation (DRGS) are treatment options for subjects with chronic knee pain. The evidence for peripheral nerve stimulation (PNS) is minimal due to a limited number of neuromodulation systems capable of targeting the distal part of the lower limbs. This study aimed to investigate the safety and efficacy externally powered PNS systems for the treatment of chronic intractable knee pain targeting the saphenous nerve. Patients suffering from chronic intractable post-surgical knee pain received landmark-guided peripheral nerve stimulation of the branches of the saphenous nerve. All implants were performed with an externally powered PNS system to avoid lead migration as a result of cross-joint lead positions tunneling towards an Implantable Pulse Generator to the trunk. Data were collected retrospectively. Subject-reported outcome was measured via numerical rating scale values on a 10-point scale measuring pain intensity at rest and in motion. Additional data were collected for the subjects treated at the Charité location, including quality of life with the SF-36 form, quality of sleep with the Pittsburgh Sleep Quality Index and mood states with the short form of the General Depression Scale. Thirty-three patients received direct to permanent implant, landmark-guided peripheral nerve stimulation of the saphenous nerve branches. Six (18.2%) subjects reported non-sufficient initial benefit from the therapy and were explanted. Two subjects were explanted due to wound infections. The total study population reported included 25 patients. These subjects reported significant improvements related to pain, quality of life, mood quality, and quality of sleep. Additionally, subjects were able to reduce their opioid medication significantly after PNS therapy. Externally powered PNS at the saphenous nerve branches is a straightforward, selective and safe technique for patients with chronic knee pain. The landmark-guided implantation technique is less invasive than classical neuromodulation techniques such as spinal cord or DRGS and complication rates remain low. Short-term results are promising and show considerable reductions in pain scores and opioid intake. Long-term results are pending.

Biopsies of Caudal Brainstem Tumors in Pediatric Patients-A Single-Center Retrospective Case Series.

OBJECTIVE: The indication for performing biopsies in patients with diffuse lesions in the brain stem is controversial. The possible risks associated with the technically challenging interventions must be balanced against clarifying the diagnosis and the possible therapeutic options. We reviewed the feasibility, risk profile, and diagnostic yield of different biopsy techniques in a pediatric cohort. METHODS: We retrospectively included all patients aged <18 years who had undergone biopsy of the caudal brainstem region (pons, medulla oblongata) at our pediatric neurosurgical center from 2009 to 2022. RESULTS: We identified 27 children. Biopsies were performed using frameless stereotactic (Varioguide; n = 12), robotic-assisted (Autoguide; n = 4), endoscopic (n = 3), and open biopsy (n = 8) techniques. Intervention-related mortality was not observed. Three patients experienced a transient postoperative neurological deficit. No patient experienced intervention-related permanent morbidity. Biopsy yielded the histopathological diagnosis in all 27 cases. Molecular analysis was feasible for 97% of the cases. The most common diagnosis was H3K27M-mutated diffuse midline glioma (60%). Low-grade gliomas were identified in 14% of patients. Overall survival was 62.5% after 24 months of follow-up. CONCLUSIONS: Biopsies of the caudal brainstem in children were feasible and safe in the presented setup. The amount of tumor material acquired allowing for an integrated diagnosis and was obtained at reasonable risk. The selection of the surgical technique depends on the tumor location and growth pattern. We recommend the performance of brainstem tumor biopsies in children at specialized centers to better understand the biology and enable possible novel therapeutic options.

Macrovascular decompression of a dolichoectatic vertebral artery via Kawase approach in a patient suffering from trigeminal neuralgia - A case report.

Introduction: Secondary trigeminal neuralgia due to vertebrobasilar dolichoectasia is a rare entity. Surgical therapy via pterional craniotomy approach and anterior petrosectomy has already been described in literature. We present an 81-year female patient suffering from left sided trigeminal neuralgia due to vertebrobasilar dolichoectasia. Research question: We show in this case report a macrovascular decompression of a dolichoectatic vertebral artery via Kawase approach. Material and methods: Successful decompression under continuous intraoperative neuromonitoring via pure Kawase approach and ventro-lateral transposition of a dolichoectatic vertebral artery through a polyester-titanium sling was achieved. Results: Postoperative the patient described an immediate improvement of the trigeminal neuralgia symptoms. At the two-month postoperative follow-up the patient remained trigeminal neuralgia painless free and suffered from a regredient facial nerve palsy. Discussion and conclusion: We report for the first time a successful macrovascular decompression of a dolichoectatic vertebral artery via Kawase approach under continuous intraoperative neuromonitoring. In-contrast to traditional suboccipital retrosigmoidal approach our strategy obtains sufficient working space and angles. Thus, adequate transposition of the dolichoectatic vessel could be achieved.

Correlation of Tumor Pathology with Fluorescein Uptake and MRI Contrast-Enhancement in Stereotactic Biopsies.

The utilization of fluorescein-guided biopsies has recently been discussed to improve and expedite operative techniques in the detection of tumor-positive tissue, as well as to avoid making sampling errors. In this study, we aimed to report our experience with fluorescein-guided biopsies and elucidate distribution patterns in different histopathological diagnoses in order to develop strategies to increase the efficiency and accuracy of this technique. We report on 45 fluorescence-guided stereotactic biopsies in 44 patients (15 female, 29 male) at our institution from March 2016 to March 2021, including 25 frame-based stereotactic biopsies and 20 frameless image-guided biopsies using VarioGuide®. A total number of 347 biopsy samples with a median of 8 samples (range: 4-18) per patient were evaluated for intraoperative fluorescein uptake and correlated to definitive histopathology. The median age at surgery was 63 years (range: 18-87). Of the acquired specimens, 63% were fluorescein positive. Final histopathology included glioblastoma (n = 16), B-cell non-Hodgkin lymphoma (n = 10), astrocytoma, IDH-mutant WHO grade III (n = 6), astrocytoma, IDH-mutant WHO grade II (n = 1), oligodendroglioma, IDH-mutant and 1p/19q-codeleted WHO grade II (n = 2), reactive CNS tissue/inflammation (n = 4), post-transplantation lymphoproliferative disorder (PTLD; n = 2), ependymoma (n = 1), infection (toxoplasmosis; n = 1), multiple sclerosis (n = 1), and metastasis (n = 1). The sensitivity for high-grade gliomas was 85%, and the specificity was 70%. For contrast-enhancing lesions, the specificity of fluorescein was 84%. The number needed to sample for contrast-enhancing lesions was three, and the overall number needed to sample for final histopathological diagnosis was five. Interestingly, in the astrocytoma, IDH-mutant WHO grade III group, 22/46 (48%) demonstrated fluorescein uptake despite no evidence for gadolinium uptake, and 73% of these were tumor-positive. In our patient series, fluorescein-guided stereotactic biopsy increases the likelihood of definitive neuropathological diagnosis, and the number needed to sample can be reduced by 50% in contrast-enhancing lesions.

Navigation accuracy and assessability of carbon fiber-reinforced PEEK instrumentation with multimodal intraoperative imaging in spinal oncology.

Radiolucent carbon-fiber reinforced PEEK (CFRP) implants have helped improve oncological follow-up and radiation therapy. Here, we investigated the performance of 3D intraoperative imaging and navigation systems for instrumentation and precision assessment of CFRP pedicle screws across the thoraco-lumbar spine. Thirty-three patients with spinal tumors underwent navigated CFRP instrumentation with intraoperative CT (iCT), robotic cone-beam CT (rCBCT) or cone-beam CT (CBCT) imaging. Two different navigation systems were used for iCT-/rCBCT- and CBCT-based navigation. Demographic, clinical and outcome data was assessed. Four blinded observers rated image quality, assessability and accuracy of CFRP pedicle screws. Inter-observer reliability was determined with Fleiss` Kappa analysis. Between 2018 and 2021, 243 CFRP screws were implanted (iCT:93, rCBCT: 99, CBCT: 51), of which 13 were non-assessable (iCT: 1, rCBCT: 9, CBCT: 3; *p = 0.0475; iCT vs. rCBCT). Navigation accuracy was highest using iCT (74%), followed by rCBCT (69%) and CBCT (49%) (*p = 0.0064; iCT vs. CBCT and rCBCT vs. CBCT). All observers rated iCT image quality higher than rCBCT/CBCT image quality (*p < 0.01) but relevant pedicle breaches were reliably identified with substantial agreement between all observers regardless of the imaging modality. Navigation accuracy for CFRP pedicle screws was considerably lower than expected from reports on titanium implants and CT may be best for reliable assessment of CFRP materials.

Reduction in wound healing complications and infection rate by lumbar CSF drainage after decompressive hemicraniectomy.

OBJECTIVE: Wound healing disorders and surgical site infections are the most frequently encountered complications after decompressive hemicraniectomy (DHC). Subgaleal CSF accumulation causes additional tension of the scalp flap and increases the risk of wound dehiscence, CSF fistula, and infection. Lumbar CSF drainage might relieve subgaleal CSF accumulation and is often used when a CSF fistula through the surgical wound appears. The aim of this study was to investigate if early prophylactic lumbar drainage might reduce the rate of postoperative wound revisions and infections after DHC. METHODS: The authors retrospectively analyzed 104 consecutive patients who underwent DHC from January 2019 to May 2021. Before January 2020, patients did not receive lumbar drainage, whereas after January 2020, patients received lumbar drainage within 3 days after DHC for a median total of 4 (IQR 2-5) days if the first postoperative CT scan confirmed open basal cisterns. The primary endpoint was the rate of severe wound healing complications requiring surgical revision. Secondary endpoints were the rate of subgaleal CSF accumulations and hygromas as well as the rate of purulent wound infections and subdural empyema. RESULTS: A total of 31 patients died during the acute phase; 34 patients with and 39 patients without lumbar drainage were included for the analysis of endpoints. The predominant underlying pathology was malignant hemispheric stroke (58.8% vs 66.7%) followed by traumatic brain injury (20.6% vs 23.1%). The rate of surgical wound revisions was significantly lower in the lumbar drainage group (5 [14.7%] vs 14 [35.9%], p = 0.04). A stepwise linear regression analysis was used to identify potential covariates associated with wound healing disorder and reduced them to lumbar drainage and BMI. One patient was subject to paradoxical herniation. However, the patient's symptoms rapidly resolved after lumbar drainage was discontinued, and he survived with only moderate deficits related to the primary disease. There was no significant difference in the rate of radiological herniation signs. The median lengths of stay in the ICU were similar, with 12 (IQR 9-23) days in the drainage group compared with 13 (IQR 11-23) days in the control group (p = 0.21). CONCLUSIONS: In patients after DHC and open basal cisterns on postoperative CT, lumbar drainage appears to be safe and reduces the rate of surgical wound revisions and intracranial infection after DHC while the risk for provoking paradoxical herniation is low early after surgery.