Optimal cerebral perfusion pressure in aneurysmal subarachnoid hemorrhage and its relation to perfusion deficits on CT-perfusion.

Preservation of optimal cerebral perfusion is a crucial part of the acute management after aneurysmal subarachnoid hemorrhage (aSAH). A few studies indicated possible benefits of maintaining a cerebral perfusion pressure (CPP) near the calculated optimal CPP (CPPopt), representing an individually optimal condition at which cerebral autoregulation functions at its best. This retrospective observational monocenter study was conducted to investigate, whether "suboptimal" perfusion with actual CPP deviating from CPPopt correlates with perfusion deficits detected by CT-perfusion (CTP). A consecutive cohort of aSAH-patients was reviewed and patients with available parameters for CPPopt-calculation, who simultaneously received CTP, were analyzed. By plotting the pressure reactivity index (PRx) versus CPP, CPP correlating the lowest PRx value was identified as CPPopt. Perfusion deficits on CTP were documented. In 86 out of 324 patients, the inclusion criteria were met. Perfusion deficits were detected in 47% (40/86) of patients. In 43% of patients, CPP was lower than CPPopt, which correlated with detected perfusion deficits (r = 0.23, p = 0.03). Perfusion deficits were found in 62% of patients with CPPCPPopt (OR 3, p = 0.01). These findings support the hypothesis, that a deviation of CPP from CPPopt is an indicator of suboptimal cerebral perfusion.

Personalized prognosis stratification of newly diagnosed glioblastoma applying a statistical decision tree model.

PURPOSE: Glioblastoma (GBM) is the most frequent glioma in adults with a high treatment resistance resulting into limited survival. The individual prognosis varies depending on individual prognostic factors, that must be considered while counseling patients with newly diagnosed GBM. The aim of this study was to elaborate a risk stratification algorithm based on reliable prognostic factors to facilitate a personalized prognosis estimation early on after diagnosis. METHODS: A consecutive patient cohort with confirmed GBM treated between 2010 and 2021 was retrospectively analyzed. Clinical, radiological, and molecular parameters were assessed and included in the analysis. Overall survival (OS) was the primary outcome parameter. After identifying the strongest prognostic factors, a risk stratification algorithm was elaborated with estimated odds of survival. RESULTS: A total of 462 GBM patients were analyzed. The strongest prognostic factors were Charlson Comorbidity Index (CCI), extent of tumor resection, and adjuvant treatment. Patients with CCI ≤ 1 receiving tumor resection had the highest survival odds (88% for 10 months). On the contrary, patients with CCI > 3 receiving no adjuvant treatment had the lowest survival odds (0% for 10 months). The 10-months survival rate in patients with CCI > 3 receiving adjuvant treatment was 56% for patients younger than 70 years and 22% for patients older than 70 years. CONCLUSION: A risk stratification algorithm based on significant prognostic factors allowed a personalized early prognosis estimation at the time of GBM diagnosis, that can contribute to a more personalized patient counseling.

Radiofrequency thermocoagulation under neuromonitoring guidance and general anesthesia for treatment of refractory trigeminal neuralgia.

OBJECTIVE: Radiofrequency thermocoagulation (RFT) for refractory trigeminal neuralgia is usually performed in awake patients to localize the involved trigeminal branches. It is often a painful experience. Here, we present RFT under neuromonitoring guidance and general anesthesia. METHOD: Stimulation of trigeminal branches at the foramen ovale with the tip of the RFT cannula is performed under short general anesthesia. Antidromic sensory-evoked potentials (aSEP) are recorded from the 3 trigeminal branches. The cannula is repositioned until the desired branch can be stimulated and lesioned. CONCLUSION: aSEP enable accurate localization of involved trigeminal branches during RFT and allow performing the procedure under general anesthesia.

Differentiation of multiple brain metastases and glioblastoma with multiple foci using MRI criteria.

OBJECTIVE: Glioblastoma with multiple foci (mGBM) and multiple brain metastases share several common features on magnetic resonance imaging (MRI). A reliable preoperative diagnosis would be of clinical relevance. The aim of this study was to explore the differences and similarities between mGBM and multiple brain metastases on MRI. METHODS: We performed a retrospective analysis of 50 patients with mGBM and compared them with a cohort of 50 patients with multiple brain metastases (2-10 lesions) histologically confirmed and treated at our department between 2015 and 2020. The following imaging characteristics were analyzed: lesion location, distribution, morphology, (T2-/FLAIR-weighted) connections between the lesions, patterns of contrast agent uptake, apparent diffusion coefficient (ADC)-values within the lesion, the surrounding T2-hyperintensity, and edema distribution. RESULTS: A total of 210 brain metastases and 181 mGBM lesions were analyzed. An infratentorial localization was found significantly more often in patients with multiple brain metastases compared to mGBM patients (28 vs. 1.5%, p < 0.001). A T2-connection between the lesions was detected in 63% of mGBM lesions compared to 1% of brain metastases. Cortical edema was only present in mGBM. Perifocal edema with larger areas of diffusion restriction was detected in 31% of mGBM patients, but not in patients with metastases. CONCLUSION: We identified a set of imaging features which improve preoperative diagnosis. The presence of T2-weighted imaging hyperintensity connection between the lesions and cortical edema with varying ADC-values was typical for mGBM.

Positioning of epidural electrode for motor cortex stimulation in general anesthesia based on intraoperative electrophysiological monitoring to treat refractory trigeminal neuropathic pain.

BACKGROUND: Motor cortex stimulation (MCS) represents a treatment option for refractory trigeminal neuralgia (TGN). Usually, patients need to be awake during surgery to confirm a correct position of the epidural electrode above the motor cortex, reducing patient's comfort. METHOD: Epidural cortical mapping (ECM) and motor evoked potentials (MEPs) were intraoperatively performed for correct localization of motor cortex under general anesthesia that provided comparable results to test stimulation after letting the patient to be awake during the operation. CONCLUSION: Intraoperative ECM and MEPs facilitate a confirmation of correct MCS-electrode position above the motor cortex allowing the MCS-procedure to be performed under general anesthesia.

Interaction of Optimal Cerebral Perfusion Pressure with Early Brain Injury and its Impact on Ischemic Complications and Outcome Following Aneurysmal Subarachnoid Hemorrhage.

BACKGROUND: Cerebral autoregulation is impaired early on after aneurysmal subarachnoid hemorrhage (aSAH). The study objective was to explore the pressure reactivity index (PRx) and cerebral perfusion pressure (CPP) in the earliest phase after aneurysm rupture and to address the question of whether an optimal CPP (CPPopt)-targeted management is associated with less severe early brain injury (EBI). METHODS: Patients with aSAH admitted between 2012 and 2020 were retrospectively included in this observational cohort study. The PRx was calculated as a correlation coefficient between intracranial pressure and mean arterial pressure. By plotting the PRx versus CPP, CPP correlating the lowest PRx value was identified as CPPopt. EBI was assessed by applying the Subarachnoid Hemorrhage Early Brain Edema Score (SEBES) on day 3 after ictus. An SEBES ≥ 3 was considered severe EBI. RESULTS: In 90 of 324 consecutive patients with aSAH, intracranial pressure monitoring was performed ≥ 7 days, allowing for PRx calculation and CPPopt determination. Severe EBI was associated with larger mean deviation of CPP from CPPopt 72 h after ictus (r = 0.22, p = 0.03). Progressive edema requiring decompressive hemicraniectomy was associated with larger deviation of CPP from CPPopt on day 2 (r = 0.23, p = 0.02). The higher the difference of CPP from CPPopt on day 3 the higher the mortality rate (r = 0.31, p = 0.04). CONCLUSIONS: Patients with CPP near to the calculated CPPopt in the early phase after aSAH experienced less severe EBI, less frequently received decompressive hemicraniectomy, and exhibited a lower mortality rate. A prospective evaluation of CPPopt-guided management starting in the first days after ictus is needed to confirm the clinical validity of this concept.

Effectiveness of Lumbar Cerebrospinal Fluid Drain Among Patients With Aneurysmal Subarachnoid Hemorrhage: A Randomized Clinical Trial.

Importance: After aneurysmal subarachnoid hemorrhage, the use of lumbar drains has been suggested to decrease the incidence of delayed cerebral ischemia and improve long-term outcome. Objective: To determine the effectiveness of early lumbar cerebrospinal fluid drainage added to standard of care in patients after aneurysmal subarachnoid hemorrhage. Design, Setting, and Participants: The EARLYDRAIN trial was a pragmatic, multicenter, parallel-group, open-label randomized clinical trial with blinded end point evaluation conducted at 19 centers in Germany, Switzerland, and Canada. The first patient entered January 31, 2011, and the last on January 24, 2016, after 307 randomizations. Follow-up was completed July 2016. Query and retrieval of data on missing items in the case report forms was completed in September 2020. A total of 20 randomizations were invalid, the main reason being lack of informed consent. No participants meeting all inclusion and exclusion criteria were excluded from the intention-to-treat analysis. Exclusion of patients was only performed in per-protocol sensitivity analysis. A total of 287 adult patients with acute aneurysmal subarachnoid hemorrhage of all clinical grades were analyzable. Aneurysm treatment with clipping or coiling was performed within 48 hours. Intervention: A total of 144 patients were randomized to receive an additional lumbar drain after aneurysm treatment and 143 patients to standard of care only. Early lumbar drainage with 5 mL per hour was started within 72 hours of the subarachnoid hemorrhage. Main Outcomes and Measures: Primary outcome was the rate of unfavorable outcome, defined as modified Rankin Scale score of 3 to 6 (range, 0 to 6), obtained by masked assessors 6 months after hemorrhage. Results: Of 287 included patients, 197 (68.6%) were female, and the median (IQR) age was 55 (48-63) years. Lumbar drainage started at a median (IQR) of day 2 (1-2) after aneurysmal subarachnoid hemorrhage. At 6 months, 47 patients (32.6%) in the lumbar drain group and 64 patients (44.8%) in the standard of care group had an unfavorable neurological outcome (risk ratio, 0.73; 95% CI, 0.52 to 0.98; absolute risk difference, -0.12; 95% CI, -0.23 to -0.01; P = .04). Patients treated with a lumbar drain had fewer secondary infarctions at discharge (41 patients [28.5%] vs 57 patients [39.9%]; risk ratio, 0.71; 95% CI, 0.49 to 0.99; absolute risk difference, -0.11; 95% CI, -0.22 to 0; P = .04). Conclusion and Relevance: In this trial, prophylactic lumbar drainage after aneurysmal subarachnoid hemorrhage lessened the burden of secondary infarction and decreased the rate of unfavorable outcome at 6 months. These findings support the use of lumbar drains after aneurysmal subarachnoid hemorrhage. Trial Registration: ClinicalTrials.gov Identifier: NCT01258257.

Optimizing the structure of interdisciplinary tumor boards for effective cancer care.

Introduction: Multi-professional interdisciplinary tumor boards (ITB) are essential institutions to discuss all newly diagnosed, relapsed or complex cancer patients in a team of specialists to find an optimal cancer care plan for each individual patient with regard to national and international clinical practice guidelines, patient´s preference and comorbidities. In a high-volume cancer center, entity-specific ITBs take place at least once a week discussing a large number of patients. To a high level of expertise and dedication, this also requires an enormous amount of time for physicians, cancer specialists and administrative support colleagues, especially for radiologists, pathologists, medical oncologists and radiation oncologists, who must attend all cancer-specific boards according to certification requirements. Methods: In this 15-month prospective German single-center analysis, we examined the established structures of 12 different cancer-specific ITBs at the certified Oncology Center and demonstrate tools helping to optimize processes before, during and after the boards for optimal, time-saving procedures. Results: By changing pathways, introducing revised registration protocols and new digital supports we could show that the workload of preparation by radiologists and pathologists could be reduced significantly by 22.9% (p=<0.0001) and 52.7% (p=<0.0001), respectively. Furthermore, two questions were added to all registration forms about the patient´s need for specialized palliative care support that should lead to more awareness and early integration of specialized help. Discussion: There are several ways to reduce the workload of all ITB team members while maintaining high quality recommendations and adherence to national and international guidelines.

Fight INflammation to Improve outcome after aneurysmal Subarachnoid HEmorRhage (FINISHER) trial: Study protocol for a randomized controlled trial.

RATIONALE: Aneurysmal subarachnoid hemorrhage (SAH) has high morbidity and mortality. While the primary injury results from the initial bleeding cannot currently be influenced, secondary injury through vasospasm and delayed cerebral ischemia worsens outcome and might be a target for interventions to improve outcome. To date, beside the aneurysm treatment to prevent re-bleeding and the administration of oral nimodipine, there is no therapy available, so novel treatment concepts are needed. Evidence suggests that inflammation contributes to delayed cerebral ischemia and poor outcome in SAH. Some studies suggest a beneficial effect of anti-inflammatory glucocorticoids, but there are no data from randomized controlled trials examining the efficacy of glucocorticoids. Therefore, current guidelines do not recommend the use of glucocorticoids in SAH. AIM: The Fight INflammation to Improve outcome after aneurysmal Subarachnoid HEmorRhage (FINISHER) trial aims to determine whether dexamethasone improves outcome in a clinically relevant endpoint in SAH patients. METHODS AND DESIGN: FINISHER is a multicenter, prospective, randomized, double-blinded, placebo-controlled clinical phase III trial which is testing the outcome and safety of anti-inflammatory treatment with dexamethasone in SAH patients. SAMPLE SIZE ESTIMATES: In all, 334 patients will be randomized to either dexamethasone or placebo within 48 h after SAH. The dexamethasone dose is 8 mg tds for days 1-7 and then 8 mg od for days 8-21. STUDY OUTCOME: The primary outcome is the modified Rankin Scale (mRS) at 6 months, which is dichotomized to favorable (mRS 0-3) versus unfavorable (mRS 4-6). DISCUSSION: The results of this study will provide the first phase III evidence as to whether dexamethasone improves outcome in SAH.

Prognostic differences and implications on treatment strategies between butterfly glioblastoma and glioblastoma with unilateral corpus callosum infiltration.

Approximately 25% of glioblastomas show at diagnosis a corpus callosum infiltration, which is associated with poor prognosis. The extent of corpus callosum involvement, however, ranges from partial unilateral to complete bilateral infiltration. The role of surgery in glioblastoma with corpus callosum involvement is controversial. In this study, we aimed to examine prognostic differences between glioblastoma with unilateral and glioblastoma with bilateral corpus callosum infiltration, and to evaluate possible treatment strategy implications. Patients with newly diagnosed glioblastoma from 2010 to 2019 were included. Corpus callosum infiltration was assessed in contrast-enhanced T1-weighted preoperative magnetic resonance imaging. Extent of resection, adjuvant treatments and overall survival were evaluated. Corpus callosum involvement was found in 96 (26.4%) out of 363 patients with newly diagnosed glioblastoma. Bilateral corpus callosum infiltration was found in 27 out of 96 patients (28%), and 69 patients had unilateral corpus callosum infiltration. Glioblastoma with corpus callosum affection had significantly lower median overall survival compared to glioblastoma without corpus callosum involvement (9 vs. 11 months, p = 0.02). A subgroup analysis of glioblastoma with unilateral corpus callosum infiltration revealed a significant difference in median overall survival dependent on extent of resection (6.5 without gross total resection vs. 11 months with gross total resection, Log-rank test p = 0.02). Our data confirms a shorter overall survival in glioblastoma subpopulation with corpus callosum involvement, especially for glioblastoma with bilateral corpus callosum infiltration. However, patients with partial corpus callosum infiltration undergoing gross total resection exhibited a significant survival benefit compared to their counterparts without gross total resection. Whenever reasonably achievable gross total resection should be considered as an integral part of the treatment strategy in glioblastoma with partial corpus callosum infiltration.

The value of comorbidities and illness severity scores as prognostic tools for early outcome estimation in patients with aneurysmal subarachnoid hemorrhage.

Aneurysmal subarachnoid hemorrhage (aSAH) is a severe cerebrovascular disease not only causing brain injury but also frequently inducing a significant systemic reaction affecting multiple organ systems. In addition to hemorrhage severity, comorbidities and acute extracerebral organ dysfunction may impact the prognosis after aSAH as well. The study objective was to assess the value of illness severity scores for early outcome estimation after aSAH. A retrospective analysis of consecutive aSAH patients treated from 2012 to 2020 was performed. Comorbidities were evaluated applying the Charlson comorbidity index (CCI) and the American Society of Anesthesiologists (ASA) classification. Organ dysfunction was assessed by calculating the simplified acute physiology score (SAPS II) 24 h after admission. Modified Rankin scale (mRS) at 3 months was documented. The outcome discrimination power was evaluated. A total of 315 patients were analyzed. Significant comorbidities (CCI > 3) and physical performance impairment (ASA > 3) were found in 15% and 12% of all patients, respectively. The best outcome discrimination power showed SAPS II (AUC 0.76), whereas ASA (AUC 0.65) and CCI (AUC 0.64) exhibited lower discrimination power. A SAPS II cutoff of 40 could reliably discriminate patients with good (mRS ≤ 3) from those with poor outcome (p < 0.0001). Calculation of SAPS II allowed a comprehensive depiction of acute organ dysfunctions and facilitated a reliable early prognosis estimation in our study. In direct comparison to CCI and ASA, SAPS II demonstrated the highest discrimination power and deserves a consideration as a prognostic tool after aSAH.

Regorafenib for recurrent high-grade glioma: a unicentric retrospective analysis of feasibility, efficacy, and toxicity.

We describe here 11 consecutive patients with recurrence of high-grade glioma treated with regorafenib at our university medical center. The majority of patients had MGMT promoter methylation (9/11 cases). Regorafenib was given as 2nd line systemic treatment in 6/11 patients and 3rd or higher line treatment in 5/11 patients. The median number of applied cycles was 2 with dosage reductions in 5/11. Response to treatment was observed in 4/11 (PR in 1/11, and SD in 3/11). Median overall survival for the cohort was 16.1 months, median progression-free survival 9.0 months, and median time to treatment failure 3.3 months. Side effects of any CTCAE grade were noted in all patients, hereby 6/11 with CTCAE °III-IV reactions. High-grade side effects were of dermatologic, cardiovascular, and hematologic nature. A mean treatment delay of 57.5 days (range 23-119) was noted between tumor board recommendation and treatment initiation due to the application process for off-label use in this indication. In conclusion, treatment with regorafenib in relapsed high-grade glioma is a feasible treatment option but has to be considered carefully due to the significant side effect profile.

Infratentorial ganglioglioma mimicking a cerebellar metastasis.

We report a case of an infratentorial ganglioglioma in a 56-year-old male, who underwent magnetic resonance imaging (MRI) during the diagnostic workup for a suspected lung cancer. The MRI scan revealed a space-occupying lesion of the left lobulus semilunaris superior cerebelli, which was assumed being a metastasis. The asymptomatic lesion was resected to establish the diagnosis. Histologic and immunohistochemical studies showed a ganglioglioma with World Health Organization grade I characteristics. Although ganglioglioma typically exhibits a supratentorial predilection, it should be included in the differential diagnosis of lesions occurring in the cerebellum.

The Impact of Endovascular Rescue Therapy on the Clinical and Radiological Outcome After Aneurysmal Subarachnoid Hemorrhage: A Safe and Effective Treatment Option for Hemodynamically Relevant Vasospasm?

Objective: Cerebral vasospasm (CVS) represents one of the multiple contributors to delayed cerebral ischemia (DCI) in patients with aneurysmal subarachnoid hemorrhage (aSAH). Especially the management of CVS, refractory to medical treatment, is a challenging task during the acute phase after aSAH. Endovascular rescue therapies (ERT), such as medical and mechanical dilation, are possible treatment options on an individual basis. However, data about the influence on the patients' functional outcomes are limited. This study aims to assess the impact of ERT on the long-term functional outcome in aSAH-patients with refractory CVS. Methods: We performed a retrospective analysis of aSAH patients treated between 2012 and 2018. CVS was considered refractory, if it persisted despite oral/intravenous nimodipine application and induced hypertension. The decision to perform ETR was made on an individual basis, according to the detection of "tissue at risk" on computed tomography perfusion (CTP) scans and CVS on computed tomography angiography (CTA) or digital subtraction angiography (DSA). The functional outcome was assessed according to the modified Rankin scale (mRS) 3 months after the ictus, whereas an mRS ≤ 2 was considered as a good outcome. Results: A total of 268 patients were included. Out of these, 205 patients (76.5%) were treated without ERT (group 1) and 63 patients (23.5%) with ERT (group 2). In 20 patients (31.8%) balloon dilatation was performed, in 23 patients (36.5%) intra-arterial nimodipine injection alone, and in 20 patients (31.8%) both procedures were combined. Considering only the patient group with DCI, the patients who were treated with ERT had a significantly better outcome compared to the patients without ERT (Mann-Whitney test, p = 0.02). Conclusion: Endovascular rescue therapies resulted in a significantly better functional outcome in patients with DCI compared to the patient group treated without ETR. CTP and CTA-based identification of "tissue at risk" might be a reliable tool for patient selection for performing ERT.

Defining the impact of adjuvant treatment on the prognosis of patients with inoperable glioblastoma undergoing biopsy only: does the survival benefit outweigh the treatment effort?

Patients with inoperable glioblastoma (GBM) usually experience worse prognosis compared to those in whom gross total resection (GTR) is achievable. Considering the treatment duration and its side effects identification of patients with survival benefit from treatment is essential to guarantee the best achievable quality of life. The aim of this study was to evaluate the survival benefit from radio-chemotherapy and to identify clinical, molecular, and imaging parameters associated with better outcome in patients with biopsied GBMs. Consecutive patients with inoperable GBM who underwent tumor biopsy at our department from 2005 to 2019 were retrospectively analyzed. All patients had histologically confirmed GBM and were followed up until death. The overall survival (OS) was calculated from date of diagnosis to date of death. Clinical, radiological, and molecular predictors of OS were evaluated. A total of 95 patients with biopsied primary GBM were enrolled in the study. The mean age was 64.3 ± 13.2 years; 56.8% (54/95) were male, and 43.2% (41/95) female. Median OS in the entire cohort was 5.5 months. After stratification for adjuvant treatment, a higher median OS was found in the group with adjuvant treatment (7 months, range 2-88) compared to the group without treatment (1 month, range 1-5) log-rank test, p < 0.0001. Patients with inoperable GBM undergoing biopsy indeed experience a very limited OS. Adjuvant treatment is associated with significantly longer OS compared to patients not receiving treatment and should be considered, especially in younger patients with good clinical condition at presentation.

In Vivo Vasospasm Induction by Ultrasound Application in the Chicken Chorioallantoic Membrane Model.

Cerebral vasospasm is a highly investigated phenomenon in neurovascular research. Experimental vasospasm models are irreplaceable for the evaluation of new antivasospastic drugs. In this study, we assessed the reliability of in vivo vasospasm induction by ultrasound application in the chicken chorioallantoic membrane (CAM) model. After incubation of fertilized chicken eggs for four days, a fenestration was performed to enable examination of the CAM vessels. On the thirteenth day, continuous-wave ultrasound (3 MHz, 1 W/cm2) was applied on the CAM vessels for 60 s. The ultrasound effect on the vessels was recorded by life imaging (5-MP HD-microscope camera, Leica®). The induced vessel diameter changes were evaluated in a defined time interval of 20 min using a Fiji macro. The vessel diameter before and after sonication was measured and the relative diameter reduction was determined. A first reduction of vessel diameter was observed after three minutes with an average vessel-diameter decrease to 77%. The maximum reduction in vessel diameter was reached eight minutes after sonication with an average vessel diameter decrease to 57% (mean relative diameter reduction of 43%, range 44-61%), ANOVA, p = 0.0002. The vasospasm persisted for all 20 recorded minutes post induction. Vasospasm can be reliably induced by short application of 3 MHz-ultrasound to the CAM vessels. This might be a suitable in vivo model for the evaluation of drug effects on vasospasm in an experimental setting as intermediary in the transition process from in vitro to in vivo assessment using animal models.

Ultrasound-Induced Release of Nimodipine from Drug-Loaded Block Copolymer Micelles: In Vivo Analysis.

Nimodipine prevents cerebral vasospasm and improves functional outcome after aneurysmal subarachnoid hemorrhage (aSAH). The beneficial effect is limited by low oral bioavailability of nimodipine, which resulted in an increasing use of nanocarriers with sustained intrathecal drug release in order to overcome this limitation. However, this approach facilitates only a continuous and not an on-demand nimodipine release during the peak time of vasospasm development. In this study, we aimed to assess the concept of controlled drug release from nimodipine-loaded copolymers by ultrasound application in the chicken chorioallantoic membrane (CAM) model. Nimodipine-loaded copolymers were produced with the direct dissolution method. Vasospasm of the CAM vessels was induced by means of ultrasound (Physiomed, continuous wave, 3 MHz, 1.0 W/cm2). The ultrasound-mediated nimodipine release (Physiomed, continuous wave, 1 MHz, 1.7 W/cm2) and its effect on the CAM vessels were evaluated. Measurements of vessel diameter before and after ultrasound-induced nimodipine release were performed using ImageJ. The CAM model could be successfully carried out in all 25 eggs. After vasospasm induction and before drug release, the mean vessel diameter was at 57% (range 44-61%) compared to the baseline diameter (set at 100%). After ultrasound-induced drug release, the mean vessel diameter of spastic vessels increased again to 89% (range 83-91%) of their baseline diameter, which was significant (p = 0.0002). We were able to provide a proof of concept for in vivo vasospasm induction by ultrasound application in the CAM model and subsequent resolution by ultrasound-mediated nimodipine release from nanocarriers. This concept merits further evaluation in a rat SAH model.

Radiation Exposure in the Acute Phase after Aneurysmal Subarachnoid Hemorrhage in the Era of CT Perfusion.

PURPOSE: Aneurysmal subarachnoid hemorrhage (aSAH) is associated with a high risk of developing multiple complications requiring further diagnostics including imaging associated with radiation exposure (RE). Since aSAH often affects younger patients, the obtained cumulative RE may have serious long-term health consequences. The aim of this study was to calculate the cumulative RE in the acute phase after aSAH and to identify contributors to RE. Additionally, we investigated whether there is a correlation of RE with outcome. METHODS: A retrospective analysis of patients with aSAH treated at our department from 2012 to 2018 was performed. The radiation dose of every single cranial radiological examination was calculated for every patient. The outcome was assessed according to the modified Rankin scale (mRS) 3 months after ictus. Factors associated with high RE were evaluated and the correlation of RE with outcome was assessed. RESULTS: In 268 included consecutive patients, the mean cumulative RE per patient was 39.95 mSv, ranging from 2 to 265.5 mSv. A higher RE correlated with delayed cerebral ischemia (r = 0.52, p < 0.0001), delayed infarction (r = 0.25, p < 0.0001), delayed ischemic neurological deficits (r = 0.29, p < 0.0001) and transcranial Doppler (TCD)-vasospasm (r = 0.34, p < 0.0001). Independent predictors of outcome were age (p = 0.0001), World Federation of Neurosurgical Societies (WFNS) grade (p < 0.0001) and delayed infarction (p = 0.0004), while RE did not correlate with outcome. CONCLUSION: There is a considerable imaging-related RE in aSAH patients. A meticulous decision-making process and imaging protocols with lower RE for the deployment of CT-based and fluoroscopy-based imaging is indicated in order to minimize the risk for radiation-mediated heath consequences in this patient population.

Frameless x-ray-based lead re-implantation after partial hardware removal of deep brain stimulation system with preservation of intracerebral trajectories.

BACKGROUND: Deep brain stimulation (DBS) is an established treatment for patients with medical refractory movement disorders with continuously increasing use also in other neurological and psychiatric diseases. Early and late complications can lead to revision surgeries with partial or complete DBS-system removal. In this study, we aimed to report on our experience with a frameless x-ray-based lead re-implantation technique after partial hardware removal or dysfunction of DBS-system, allowing the preservation of intracerebral trajectories. METHODS: We describe a surgical procedure with complete implant removal due to infection except for the intracranial part of the electrode and with non-stereotactic electrode re-implantation. A retrospective analysis of a patient series treated using this technique was performed and the surgical outcome was evaluated including radiological and clinical parameters. RESULTS: A total of 8 DBS-patients with lead re-implantation using the frameless x-ray-based method were enrolled in the study. A revision of 14 leads was performed, whereof a successful lead re-implantation could be achieved without any problems in 10 leads (71%). In two patients (one patient with dystonia and one patient with tremor), the procedure was not successful, so we placed both leads frame-based stereotactically. CONCLUSIONS: The described x-ray-based technique allows a reliable frameless electrode re-implantation after infection and electrode dysfunction and might represent an efficient alternative to frame-based procedures for lead revision making the preservation of intracerebral trajectories possible.