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Helena Knotkova1,2, Ricardo Cruciani1–3, Volker M Tronnier4, Dirk Rasche41Department of Pain Medicine and Palliative Care, Research Division, Institute for Non-invasive Brain Stimulation, Beth Israel Medical Center, New York, NY, USA; 2Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA; 3Department of Anesthesiology, Albert Einstein College of Medicine, Bronx, NY, USA; 4Department of Neurosurgery, University of Lübeck, GermanyAbstract: Phantom-limb pain (PLP) belongs among difficult-to-treat chronic pain syndromes. Treatment options for PLP are to a large degree implicated by the level of understanding the mechanisms and nature of PLP. Research and clinical findings acknowledge the neuropathic nature of PLP and also suggest that both peripheral as well as central mechanisms, including neuroplastic changes in central nervous system, can contribute to PLP. Neuroimaging studies in PLP have indicated a relation between PLP and the neuroplastic changes. Further, it has been shown that the pathological neuroplastic changes could be reverted, and there is a parallel between an improvement (reversal) of the neuroplastic changes in PLP and pain relief. These findings facilitated explorations of novel neuromodulatory treatment strategies, adding to the variety of treatment approaches in PLP. Overall, available treatment options in PLP include pharmacological treatment, supportive non-pharmacological non-invasive strategies (eg, neuromodulation using transcranial magnetic stimulation, visual feedback therapy, or motor imagery; peripheral transcutaneous electrical nerve stimulation, physical therapy, reflexology, or various psychotherapeutic approaches), and invasive treatment strategies (eg, surgical destructive procedures, nerve blocks, or invasive neuromodulation using deep brain stimulation, motor cortex stimulation, or spinal cord stimulation). Venues of further development in PLP management include a technological and methodological improvement of existing treatment methods, an implementation of new techniques and products, and a development of new treatment approaches.Keywords: phantom-limb pain (PLP), neuropathic pain, non-invasive treatment, invasive treatment, neuromodulation

Objectives: Reliable imaging of eloquent tumour-adjacent brain areas is necessary for planning function-preserving neurosurgery. This study evaluates the potential diagnostic benefits of presurgical functional magnetic resonance imaging (fMRI) in comparison to a detailed analysis of morphological MRI data.Methods: Standardised preoperative functional and structural neuroimaging was performed on 77 patients with rolandic mass lesions at 1.5 Tesla. The central region of both hemispheres was allocated using six morphological and three functional landmarks.Results: fMRI enabled localisation of the motor hand area in 76/77 patients, which was significantly superior to analysis of structural MRI (confident localisation of motor hand area in 66/77 patients; p < 0.002). FMRI provided additional diagnostic information in 96% (tongue representation) and 97% (foot representation) of patients. FMRI-based presurgical risk assessment correlated in 88% with a positive postoperative clinical outcome.Conclusion: Routine presurgical FMRI allows for superior assessment of the spatial relationship between brain tumour and motor cortex compared with a very detailed analysis of structural 3D MRI, thus significantly facilitating the preoperative risk-benefit assessment and function-preserving surgery. The additional imaging time seems justified. FMRI has the potential to reduce postoperative morbidity and therefore hospitalisation time. [ABSTRACT FROM AUTHOR]

Surgical procedures for treating neuropathic pain, including trigeminal neuralgia (TGN), are categorized into three groups: decompression, ablation, and neuromodulation. Microvascular decompression is the only causal therapy for TGN, applicable favorably in cases of classical TGN due to a vascular nerve conflict. Ablative procedures include both percutaneous and radiosurgical methods, which are mainly used for idiopathic trigeminal neuralgia. For irreversible neuropathies of the trigeminal nerve, the algorithm for other neuropathic pain conditions should be considered, along with the potential use of neuromodulatory techniques. When selecting a therapy, diagnosis, medication side effects, individual patient risks, and treatment outcomes must all be taken into account (current S1 guideline from the German Society of Neurology)., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Background: Volatile anesthetics have shown neuroprotective effects in preclinical studies, but clinical data on their use after aneurysmal subarachnoid hemorrhage (aSAH) are limited. This study aimed to analyze whether the use of volatile anesthetics for neurocritical care sedation affects the incidence of delayed cerebral ischemia (DCI), cerebral vasospasm (CVS), DCI-related infarction, or functional outcome., Methods: Data were retrospectively collected for ventilated aSAH patients (2016-2022), who received sedation for at least 180 hours. For comparative analysis, patients were assigned to a control and a study group according to the sedation used (intravenous vs. volatile sedation). Logistic regression analysis was performed to identify independent predictors of DCI, CVS, DCI-related infarction, and functional outcome., Results: Ninety-nine patients with a median age of 58 years (interquartile range: 52-65 years) were included. Forty-seven patients (47%) received intravenous sedation, while 52 patients (53%) received (additional) volatile sedation with isoflurane (n = 30, 58%) or sevoflurane (n = 22, 42%) for a median duration of 169 hours (range: 5-298 hours). There were no significant differences between the 2 groups regarding the occurrence of DCI, angiographic CVS, DCI-related infarction, or functional outcome. In a multivariable logistic regression analysis, the use of volatile anesthetics had no impact on the incidence of DCI-related infarction or the patients' functional outcome., Conclusions: Volatile sedation in aSAH patients is not associated with the incidence of DCI, CVS, DCI-related infarction, or functional outcome. Although we could not demonstrate neuroprotective effects of volatile anesthetics, our results suggest that volatile sedation after aSAH has no negative effect on the patient's outcome., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Objective: Prone positioning (PP) is an established treatment modality for respiratory failure. After aneurysmal subarachnoid hemorrhage (aSAH), PP is rarely performed considering the risk of intracranial hypertension. The aim of this study was to analyze the effects of PP on intracranial pressure (ICP), cerebral perfusion pressure (CPP) and cerebral oxygenation following aSAH., Patients and Methods: Demographic and clinical data of aSAH patients admitted over a 6-year period and treated with PP due to respiratory insufficiency were retrospectively analyzed. ICP, CPP, brain tissue oxygenation (pBrO2), respiratory parameters and ventilator settings were analyzed before and during PP., Results: Thirty patients receiving invasive multimodal neuromonitoring were included. Overall, 97 PP sessions were performed. Mean arterial oxygenation and pBrO2 increased significantly during PP. We found a significant increase in median ICP compared to the baseline level in supine position. No significant changes in CPP were observed. Five PP sessions had to be terminated early due to medically refractory ICP-crisis. The affected patients were younger (p = 0.02) with significantly higher baseline ICP values (p = 0.009). Baseline ICP correlates significantly (p < 0.001) with ICP 1 h (R: 0.57) and 4 h (R: 0.55) after onset of PP., Conclusion: PP in aSAH patients with respiratory insufficiency is an effective therapeutic option improving arterial and global cerebral oxygenation without compromising CPP. The significant increase in ICP was moderate in most sessions. However, as some patients experience intolerable ICP crises during PP, continuous ICP-Monitoring is considered mandatory. Patients with elevated baseline ICP and reduced intracranial compliance should not be considered for PP., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Objective: Volatile sedation after aneurysmal subarachnoid hemorrhage (aSAH) promises several advantages, but there are still concerns regarding intracranial hypertension due to vasodilatory effects. We prospectively analyzed cerebral parameters during the switch from intravenous to volatile sedation with isoflurane in patients with poor-grade (World Federation of Neurosurgical Societies grade 4-5) aSAH., Methods: Eleven patients were included in this prospective observational study. Between day 3 and 5 after admission, intravenous sedation was switched to isoflurane using the Sedaconda Anesthetic Conserving Device (Sedana Medical, Danderyd, Sweden). Intracranial pressure (ICP), cerebral perfusion pressure (CPP), brain tissue oxygenation (PBrO 2 ), cerebral mean flow velocities (MFVs; transcranial Doppler ultrasound) and regional cerebral oxygen saturation (rSO 2 , near-infrared spectroscopy monitoring), as well as cardiopulmonary parameters were assessed before and after the sedation switch (-12 to +12 hours). Additionally, perfusion computed tomography data during intravenous and volatile sedation were analyzed retrospectively for changes in cerebral blood flow., Results: There were no significant changes in mean ICP, CPP, and PBrO 2 after the sedation switch to isoflurane. Mean rSO 2 showed a non-significant trend towards higher values, and mean MFV in the middle cerebral arteries increased significantly after the initiation of volatile sedation. Isoflurane sedation resulted in a significantly increased norepinephrine administration. Despite an increase in mean inspiratory pressure, we observed a significant increase in mean partial arterial pressure of carbon dioxide., Conclusions: Isoflurane sedation does not compromise ICP or cerebral oxygenation in poor-grade aSAH patients, but the significant depression of CPP could limit the use of volatiles in case of hemodynamic instability or high vasopressor demand., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Intra-arterial nimodipine (IAN) injections are performed in refractory delayed cerebral ischemia (DCI) related to cerebral vasospasm (CVS) after spontaneous subarachnoid hemorrhage (sSAH), but the clinical benefits are inconclusive and angiographic treatment failure is observed. We analyzed angiographic IAN response in a detailed vessel-specific manner and examined the impact of poor angiographic response on the further clinical course., Methods: Clinical data were retrospectively assessed in patients with spontaneous subarachnoid hemorrhage with symptomatic CVS receiving IAN bolus treatment. Clinical and angiographic predictors for poor angiographic response, DCI-related infarction, and unfavorable outcome were analyzed., Results: Eighty-nine patients were included and 356 treated vessel segments, mainly located in the anterior circulation (93%), were analyzed. Angiographic response was good in 77% of the treated segments. Older age, poor World Federation of Neurosurgical Societies (WFNS) grade 4-5 and early onset of CVS were independently associated with poor angiographic response. The factors short-segment, distal, and bilateral CVS as well as treatment of multiple vessel segments, WFNS grade 4-5, and early onset of CVS were significantly associated with an increased risk of DCI-related infarction. Clinical outcome was significantly influenced by poor WFNS grade and early onset of CVS, whereas poor angiographic response was not related to DCI-related infarction or unfavorable outcome., Conclusions: The risk of angiographic treatment failure is significantly increased in older patients and those with poor WFNS grade as in cases of early-onset CVS. Although the extent of angiographic CVS significantly affected the development of DCI-related infarction, poor angiographic response had no impact on cerebral infarction and clinical outcome., (Copyright © 2022 Elsevier Inc. All rights reserved.)