Risk factors of recurrence in chronic subdural hematoma and a proposed extended classification of internal architecture as a predictor of recurrence.

Chronic subdural hematomas (cSDHs) constitute one of the most prevalent intracranial disease entities requiring surgical treatment. Although mostly taking a benign course, recurrence after treatment is common and associated with additional morbidity and costs. Aim of this study was to develop hematoma-specific characteristics associated with risk of recurrence. All consecutive patients treated for cSDH in a single university hospital between 2015 and 2019 were retrospectively considered for inclusion. Size, volume, and midline shift were noted alongside relevant patient-specific factors. We applied an extended morphological classification system based on internal architecture in CT imaging consisting of eight hematoma subtypes. A logistic regression model was used to assess the classification's performance on predicting hematoma recurrence. Recurrence was observed in 122 (32.0%) of 381 included patients. Apart from postoperative depressed brain volume (OR 1.005; 95% CI 1.000 to 1.010; p = 0.048), neither demographic nor factors related to patient comorbidity affected recurrence. The extended hematoma classification was identified as a significant predictor of recurrence (OR 1.518; 95% CI 1.275 to 1.808; p < 0.001). The highest recurrence rates were observed in hematomas of the homogenous (isodense: 41.4%; hypodense: 45.0%) and sedimented (50.0%) types. Our results support that internal architecture subtypes might represent stages in the natural history of chronic subdural hematoma. Detection and treatment at a later stage of spontaneous repair can result in a reduced risk of recurrence. Based on their high risk of recurrence, we advocate follow-up after treatment of sedimented and homogenous hematomas.

18F-FET-PET-guided gross total resection improves overall survival in patients with WHO grade III/IV glioma: moving towards a multimodal imaging-guided resection.

PURPOSE: PET using radiolabeled amino acid [18F]-fluoro-ethyl-L-tyrosine (FET-PET) is a well-established imaging modality for glioma diagnostics. The biological tumor volume (BTV) as depicted by FET-PET often differs in volume and location from tumor volume of contrast enhancement (CE) in MRI. Our aim was to investigate whether a gross total resection of BTVs defined as < 1 cm3 of residual BTV (PET GTR) correlates with better oncological outcome. METHODS: We retrospectively analyzed imaging and survival data from patients with primary and recurrent WHO grade III or IV gliomas who underwent FET-PET before surgical resection. Tumor overlap between FET-PET and CE was evaluated. Completeness of FET-PET resection (PET GTR) was calculated after superimposition and semi-automated segmentation of pre-operative FET-PET and postoperative MRI imaging. Survival analysis was performed using the Kaplan-Meier method and the log-rank test. RESULTS: From 30 included patients, PET GTR was achieved in 20 patients. Patients with PET GTR showed improved median OS with 19.3 compared to 13.7 months for patients with residual FET uptake (p = 0.007; HR 0.3; 95% CI 0.12-0.76). This finding remained as independent prognostic factor after performing multivariate analysis (HR 0.19, 95% CI 0.06-0.62, p = 0.006). Other survival influencing factors such as age, IDH-mutation, MGMT promotor status, and adjuvant treatment modalities were equally distributed between both groups. CONCLUSION: Our results suggest that PET GTR improves the OS in patients with WHO grade III or IV gliomas. A multimodal imaging approach including FET-PET for surgical planning in newly diagnosed and recurrent tumors may improve the oncological outcome in glioma patients.

Surgical nuances and placement of subgaleal drains for supratentorial procedures-a prospective analysis of efficacy and outcome in 150 craniotomies.

BACKGROUND: For supratentorial craniotomy, surgical access, and closure technique, including placement of subgaleal drains, may vary considerably. The influence of surgical nuances on postoperative complications such as cerebrospinal fluid leakage or impaired wound healing overall remains largely unclear. With this study, we are reporting our experiences and the impact of our clinical routines on outcome in a prospectively collected data set. METHOD: We prospectively observed 150 consecutive patients undergoing supratentorial craniotomy and recorded technical variables (type/length of incision, size of craniotomy, technique of dural and skin closure, type of dressing, and placement of subgaleal drains). Outcome variables (subgaleal hematoma/CSF collection, periorbital edema, impairment of wound healing, infection, and need for operative revision) were recorded at time of discharge and at late follow-up. RESULTS: Early subgaleal fluid collection was observed in 36.7% (2.8% at the late follow-up), and impaired wound healing was recorded in 3.3% of all cases, with an overall need for operative revision of 6.7%. Neither usage of dural sealants, lack of watertight dural closure, and presence of subgaleal drains, nor type of skin closure or dressing influenced outcome. Curved incisions, larger craniotomy, and tumor size, however, were associated with an increase in early CSF or hematoma collection (p < 0.0001, p = 0.001, p < 0.01 resp.), and larger craniotomy size was associated with longer persistence of subgaleal fluid collections (p < 0.05). CONCLUSIONS: Based on our setting, individual surgical nuances such as the type of dural closure and the use of subgaleal drains resulted in a comparable complication rate and outcome. Subgaleal fluid collections were frequently observed after supratentorial procedures, irrespective of the closing technique employed, and resolve spontaneously in the majority of cases without significant sequelae. Our results are limited due to the observational nature in our single-center study and need to be validated by supportive prospective randomized design.

Imaging of Ventriculoperitoneal Shunt Complications: Comparison of Whole Body Low-Dose Computed Tomography and Radiographic Shunt Series.

OBJECTIVE: To determine diagnostic value and radiation exposure of low-dose computed tomography (LD-CT) compared to radiographic shunt series (SS) for the detection of ventriculoperitoneal (VP) shunt complications. METHODS: Fourteen VP shunts were implanted in 7 swine cadavers. Mechanical complications were induced in 50% of VP shunts. Low-dose CT (80 kVp, 10 mAs, Pitch = 1.5) and SS were acquired. Dose area product (DAP) and effective doses for SS and LD-CT were collected. Scoring of diagnostic confidence and blinded readings of SS and CT data were performed. RESULTS: The sensitivity of LD-CT was high (0.97; 95% confidence interval, 0.91-1.00) with excellent interobserver agreement (κ = 0.88). Similarly, the sensitivity of SS was high (0.82; 95% confidence interval, 0.68-0.95) with good interobserver agreement (κ = 0.68). In contrast, LD-CT was associated with significantly higher diagnostic confidence (4.64 ± 0.41 vs 2.71 ± 0.73; P < 0.01) and significantly lower radiation exposure (effective dose: 0.26 mSv vs 1.06 mSv; DAP: 265.4 µGym vs 724.8 µGym; P < 0.001). CONCLUSIONS: For the assessment of suspected VP shunt complications, LD-CT provides excellent sensitivity and higher diagnostic confidence with lower radiation exposure compared with SS.

Evaluation of whole body Ultralow-Dose CT for the assessment of ventriculoperitoneal shunt complications: an experimental ex-vivo study in a swine model.

OBJECTIVE: To evaluate the suitability of whole body Ultralow-dose CT (ULD-CT) as a diagnostic tool for the evaluation of ventriculoperitoneal shunt (VP-shunt) complications with special regards to radiation dose and image quality. METHODS: Fourteen VP-shunts were implanted in 7 swine cadavers (weight: 55-70 kg). Twenty-two mechanical complications (extracranial and extraperitoneal malpositioning, breakages, disconnections) were induced in nine VP-shunts. Ten ULD-CT scans with different parameters (tube voltage: 80, 100, 120 kV; tube current: 20 or 50 mAs; Pitch (P): 1 or 1.5) were acquired; the combination of 120 kV and 50 mAs was omitted. Radiation dose estimation, blinded readings, and quantitative and qualitative assessment of the CT-data were performed. RESULTS: Effective radiation doses varied between 0.44 ± 0.06 and 2.55 ± 0.35 mSv. ULD-CT protocols provided a mean sensitivity (i.e., correctly detected shunt complications) of 98.2 %. Unnoticed or incorrectly identified complications did not exceed one complication (4.5 %) in any ULD-CT protocol. Diagnostic confidence was sufficient for all ULD-CT protocols except for protocols with 80 kV and 20 mAs. CONCLUSIONS: ULD-CT allows accurate detection of VP-shunt complications at radiation doses similar or lower than reported for a radiographic shunt series. At the tested radiation dose levels, ULD-CT thus provides an alternative to a radiographic shunt series. KEY POINTS: • Ultralow-dose CT accurately detects Ventriculoperitoneal Shunt complications. • Radiation dosage is similar or lower than reported for a radiographic shunt series. • Ultralow-dose CT potentially shortens the diagnostic process when shunt complications are suspected.

Development and first results of a national databank on care and treatment outcome after traumatic brain injury.

PURPOSE: In absence of comprehensive data collection on traumatic brain injury (TBI), the German Society for Neurosurgery (DGNC) and the German Society for Trauma Surgery (DGU) developed a TBI databank for German-speaking countries. METHODS: From 2016 to 2020, the TBI databank DGNC/DGU was implemented as a module of the TraumaRegister (TR) DGU and tested in a 15-month pilot phase. Since its official launch in 2021, patients from the TR-DGU (intermediate or intensive care unit admission via shock room) with TBI (AIS head ≥ 1) can be enrolled. A data set of > 300 clinical, imaging, and laboratory variables, harmonized with other international TBI data collection structures is documented, and the treatment outcome is evaluated after 6- and 12 months. RESULTS: For this analysis, 318 patients in the TBI databank could be included (median age 58 years; 71% men). Falls were the most common cause of injury (55%), and antithrombotic medication was frequent (28%). Severe or moderate TBI were only present in 55% of patients, while 45% suffered a mild injury. Nevertheless, intracranial pathologies were present in 95% of brain imaging with traumatic subarachnoid hemorrhages (76%) being the most common. Intracranial surgeries were performed in 42% of cases. In-hospital mortality after TBI was 21% and surviving patients could be discharged after a median hospital stay of 11 days. At the 6-and 12 months follow-up, a favorable outcome was achieved by 70% and 90% of the participating TBI patients, respectively. Compared to a European cohort of 2138 TBI patients treated in the ICU between 2014 and 2017, patients in the TBI databank were already older, frailer, fell more commonly at home. CONCLUSION: Within five years, the TBI databank DGNC/DGU of the TR-DGU could be established and is since then prospectively enrolling TBI patients in German-speaking countries. With its large and harmonized data set and a 12-month follow-up, the TBI databank is a unique project in Europe, already allowing comparisons to other data collection structures and indicating a demographic change towards older and frailer TBI patients in Germany.

Chronic Subdural Hematoma.

BACKGROUND: Chronic subdural hematoma (cSDH) is typically a disease that affects the elderly. Neurosurgical evacuation is generally indicated for hematomas that are wider than the thickness of the skull. The available guidelines do not address the common clinical issue of the proper management of antithrombotic drugs that the patient has been taking up to the time of diagnosis of the cSDH. Whether antithrombotic treatment should be stopped or continued depends on whether the concern about spontaneous or postoperative intracranial bleeding, and a presumably higher rate of progression or recurrence, with continued medication outweighs the concern about a possibly higher rate of thrombotic complications if it is stopped. METHODS: In this article, we review publications from January 2015 to October 2020 addressing the issue of the management of antithrombotics in patients with cSDH that were retrieved by a selective search in the Pubmed and EMBASE databases, and we present the findings of a cohort study of 395 patients who underwent surgery for cSDH consecutively between October 2014 and December 2019. RESULTS: The findings published in the literature are difficult to summarize concisely because of the heterogeneity of study designs. Among the seven studies in which a group of patients on antithrombotics was compared with a control group, four revealed significant differences with respect to the risk of thromboembolic complications depending on previous antithrombotic use and the duration of discontinuation, while three others did not. In our own cohort, discontinuation of antithrombotics (including both plasmatic and antiplatelet drugs) was associated with thrombotic complications in 9.1% of patients. CONCLUSION: These findings imply that the management of antithrombotics should be dealt with critically on an individual basis. In patients with cSDH who are at elevated risk, an early restart of antithrombotic treatment or even an operation under continued antithrombotic therapy should be considered.

MRI appearance of chronic subdural hematoma.

Objective: We aimed to describe the magnetic resonance imaging (MRI) characteristics of chronic subdural hematoma (cSDH) and to ascribe MRI patterns. Methods: A total of 20 patients having 27 subdural hematomas underwent contrast-enhanced (CE) MRI of the brain at our institution between April 2019 and May 2021. The images were independently evaluated by two experienced neuroradiologists with regard to imaging characteristics on T1w, T2w, T2*-GRE, FLAIR, diffusion-weighted magnetic resonance imaging (DWI), and CE images. Results: The signal characteristics of cSDH on T1- and T2-weighted images were rather heterogeneous. The majority of hematomas (74%) had internal septations. Surprisingly, contrast enhancement along the outer membrane adjacent to the cranium was noticed in all hematomas. There was also contrast enhancement along the inner membrane adjacent to the brain in more than one-third of the hematomas (37%). In approximately two-thirds of the cSDH (62%), there was a mass-like enhancement of the hematoma. Most hematomas (89%) were partially hypointense on T2*-GRE and/or susceptibility-weighted imaging (SWI). Restricted diffusion was detected in approximately one-third of the hematomas (33%). Conclusion: Consistent contrast enhancement along the outer membrane, triangular-shaped contrast enhancement at the borders of the cSDH, and infrequent enhancement of the inner membrane may help to distinguish cSDH from other entities such as empyema and tumors. Mass-like enhancement may refer to non-solid hematomas and could be an indicator for hematoma growth and a possible surrogate for successful endovascular embolization. Restricted diffusion in a subdural mass is not specific for empyema but may also be found in cSDH.

Seizure after surgical treatment of chronic subdural hematoma-Associated factors and effect on outcome.

Introduction: Chronic subdural hematoma (cSDH) is becoming more prevalent due to population aging and the increasing use of antithrombotic drugs. Postoperative seizure in cSDH have a negative effect on outcome, and there currently no consensus regarding prophylactic anti-epileptic drug (AED) treatment. The objective of this study was to evaluate predisposing and triggering factors associated with postoperative epileptic seizure in patients with cSDH. Methods: All patients, who were surgically treated for cSDH in a single tertiary care center between 2015 and 2019, were considered for inclusion. Relevant patient- and hematoma-specific characteristics were retrospectively extracted from hospital records. Paroxysmal events categorized by the treating physician as suspected postoperative seizures were noted. The clinical outcome was extracted from the last available follow-up visit and classified according to the Glasgow outcome scale (GOS). Results: Of the included 349 patients, 54 (15.5%) developed suspected postoperative epileptic complications in the form of early seizure (≤ 7 days) in 11 patients (3.2%) and late seizure (>7 days) in 43 patients (12.3%). In the logistic regression analysis, solely depressed brain volume (supratentorial volume (ml) not filled with re-expanded brain) was independently associated with postoperative seizure (odds ratio [OR] 1.006, 95% CI: 1.001-1.011; p = 0.034). The occurrence of postoperative seizure (OR 6.210, 95% CI: 2.704-14.258; p < 0.001) and preoperative Markwalder grading (OR 2.919, 95% CI: 1.538-5.543; p = 0.001) were independently associated with unfavorable (GOS1-3) outcome. Conclusion: Larger postoperative depressed brain volume was the only factor independently associated with suspected postoperative seizure, and it could help identify a subgroup of patients with higher susceptibility to epileptic events. Based on our data, no formal recommendation can be made regarding the prophylactic use of anti-epileptic drugs. Nevertheless, the relative safety of new generation AEDs and the detrimental effect of postoperative seizure on outcome may justify its use in a selected patient population.

Elevated concentrations of macrophage migration inhibitory factor in serum and cerebral microdialysate are associated with delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage.

Objective: Inflammation is increasingly recognized to be involved in the pathophysiology of aneurysmal subarachnoid hemorrhage (aSAH) and may increase the susceptibility to delayed cerebral ischemia (DCI). Macrophage migration inhibitory factor (MIF) has been shown to be elevated in serum and cerebrospinal fluid (CSF) after aSAH. Here, we determined MIF levels in serum, CSF and cerebral microdialysate (MD) at different time-points after aSAH and evaluated their clinical implications. Methods: MIF levels were measured in serum, CSF and MD obtained from 30 aSAH patients during early (EPd1-4), critical (CPd5-15) and late (LPd16-21) phase after hemorrhage. For subgroup analyses, patients were stratified based on demographic and clinical data. Results: MIF levels in serum increased during CPd5-15 and decreased again during LPd16-21, while CSF levels showed little changes over time. MD levels peaked during EPd1-4, decreased during CPd5-15 and increased again during LPd16-21. Subgroup analyses revealed significantly higher serum levels in patients with aneurysms located in the anterior vs. posterior circulation during CPd5-15 (17.3 [15.1-21.1] vs. 10.0 [8.4-11.5] ng/ml, p = 0.009) and in patients with DCI vs. no DCI during CPd5-15 (17.9 [15.1-22.7] vs. 11.9 [8.9-15.9] ng/ml, p = 0.026) and LPd16-21 (17.4 [11.7-27.9] vs. 11.3 [9.2-12.2] ng/ml, p = 0.021). In addition, MIF levels in MD during CPd5-15 were significantly higher in patients with DCI vs. no DCI (3.6 [1.8-10.7] vs. 0.2 [0.1-0.7] ng/ml, p = 0.026), while CSF levels during the whole observation period were similar in all subgroups. Conclusion: Our findings in a small cohort of aSAH patients provide preliminary data on systemic, global cerebral and local cerebral MIF levels after aSAH and their clinical implications. Clinical trial registration: ClinicalTrials.gov, identifier: NCT02142166.

A Retrospective Analysis of Randomized Controlled Trials on Traumatic Brain Injury: Evaluation of CONSORT Item Adherence.

Traumatic brain injury (TBI) contributes to death and disability, resulting in an enormous individual and socio-economic challenges. Despite huge efforts, there are still controversies on treatment strategies and early outcome estimation. We evaluate current randomized controlled trials (RCTs) on TBI according to their fulfillment of the CONSORT (Consolidated Statement of Reporting Trials) statement's criteria as a marker of transparency and the quality of study planning and realization. A PubMed search for RCTs on TBI (January 2014-December 2019) was carried out. After screening of the abstracts (n = 1.926), the suitable full text manuscripts (n = 72) were assessed for the fulfillment of the CONSORT criteria. The mean ratio of consort statement fulfillment was 59% (±13%), 31% of the included studies (n = 22) complied with less than 50% of the CONSORT criteria. Citation frequency was moderately related to ratio of CONSORT item fulfillment (r = 0.4877; p < 0.0001) and citation frequency per year (r = 0.5249; p < 0.0001). The ratio of CONSORT criteria fulfillment was associated with the impact factor of the publishing journal (r = 0.6428; p < 0.0001). Essential data for study interpretation, such as sample size determination (item 7a), participant flow (item 13a) as well as losses and exclusions (item 13b), were only reported in 53%, 60% and 63%, respectively. Reporting and methodological aspects in RCTs on TBI still may be improved. Thus, the interpretation of study results may be hampered due to methodological weaknesses.

An altered posterior question-mark incision is associated with a reduced infection rate of cranioplasty after decompressive hemicraniectomy.

OBJECTIVE: Performing a cranioplasty (CP) after decompressive craniotomy is a straightforward neurosurgical procedure, but it remains associated with a high complication rate. Surgical site infection (SSI), aseptic bone resorption (aBR), and need for a secondary CP are the most common complications. This observational study aimed to identify modifiable risk factors to prevent CP failure. METHODS: A retrospective analysis was performed of all patients who underwent CP following decompressive hemicraniectomy (DHC) between 2010 and 2018 at a single institution. Predictors of SSI, aBR, and need for allograft CP were evaluated in a univariate analysis and multivariate logistic regression model. RESULTS: One hundred eighty-six patients treated with CP after DHC were included. The diagnoses leading to a DHC were as follows: stroke (83 patients, 44.6%), traumatic brain injury (55 patients, 29.6%), subarachnoid hemorrhage (33 patients, 17.7%), and intracerebral hemorrhage (15 patients, 8.1%). Post-CP SSI occurred in 25 patients (13.4%), whereas aBR occurred in 32 cases (17.2%). An altered posterior question-mark incision, ending behind the ear, was associated with a significantly lower infection rate and CP failure, compared to the classic question-mark incision (6.3% vs 18.4%; p = 0.021). The only significant predictor of aBR was patient age, in which those developing resorption were on average 16 years younger than those without aBR (p < 0.001). CONCLUSIONS: The primary goal of this retrospective cohort analysis was to identify adjustable risk factors to prevent post-CP complications. In this analysis, a posterior question-mark incision proved beneficial regarding infection and CP failure. The authors believe that these findings are caused by the better vascularized skin flap due to preservation of the superficial temporal artery and partial preservation of the occipital artery. In this trial, the posterior question-mark incision was identified as an easily and costless adaptable technique to reduce CP failure rates.

High-Pitch Low-Dose Whole-Body Computed Tomography for the Assessment of Ventriculoperitoneal Shunts in a Pediatric Patient Model: An Experimental Ex Vivo Study in Rabbits.

OBJECTIVE: The aim of this study was to assess the diagnostic value of whole-body low-dose (LD) computed tomography (CT) for the detection of ventriculoperitoneal (VP) shunt complications in pediatric patients compared with radiographic shunt series (SS) in an ex vivo rabbit animal model. METHODS: In the first step, 2 optimized LD-CT imaging protocols, with high pitch (pitch, 3.2), low tube voltages (70 kVp and 80 kVp), and using both filtered back projection and iterative reconstruction, were assessed on a 16-cm solid polymethylmethacrylate phantom regarding signal-to-noise ratio and radiation dose. Taking both radiation dose and signal-to-noise ratio into account, the LD-CT protocol (80 kVp; 4 mA; pitch, 3.2) was identified as most appropriate and therefore applied in this study.After identification of appropriate LD-CT protocol, 12 VP shunts were implanted in 6 rabbit cadavers (mean weight, 5.1 kg). Twenty-four mechanical complications (extracranial and extraperitoneal malpositioning, breakages, and disconnections) were induced in half of the VP shunts. Low-dose CT and conventional SS were acquired in standard fashion. Dose-area products (DAPs) for SS and LD-CT were collected; effective radiation doses for both SS and LD-CT were estimated using CT-Expo (v. 2.3.1.) and age-specific effective dose (ED) estimates. Qualitative scoring of diagnostic confidence on a 5-point Likert scale (1, very low diagnostic confidence; 5, excellent diagnostic confidence) and blinded readings of both SS and LD-CTs were performed. RESULTS: Among the 24 VP shunt complications, LD-CT yielded excellent sensitivity and specificity for the detection of VP shunt complications (sensitivity, 0.98; specificity, 1; 95% confidence interval, 0.92-1) with excellent interobserver agreement (κ = 0.90). Shunt series yielded good sensitivity and specificity (sensitivity, 0.75; specificity, 1; 95% confidence interval, 0.58-0.92) with moderate interobserver agreement (κ = 0.56). No false-positive findings were registered. Compared with SS, LD-CT yielded significantly lower ED and DAPs (ED, 0.039 vs 0.062 mSv; DAP, 20.5 vs 26.3; P < 0.05). CONCLUSIONS: In this experimental ex vivo pediatric patient model, LD-CT yields excellent sensitivity for the detection of VP shunt complications at higher diagnostic confidence and lower radiation exposure compared with SS.