Brain Midline Shift Measurement and Its Automation: A Review of Techniques and Algorithms

RapidpulseTM cyclic aspiration system for acute ischemic stroke due to large vessel occlusions

BACKGROUND

The best strategy to achieve optimal reperfusion outcomes during mechanical thrombectomy remains to be defined. The RapidPulseTM Cyclic Aspiration System is a novel technology, delivering high-frequency pulsed vacuum forces to increase the efficiency of aspiration thrombectomy.

METHODS

Prospective, multicenter, open-label, core lab-adjudicated, two-arm study comparing safety and efficacy of a feasibility version of the RapidPulseTM system compared with contemporary controls. Primary endpoint was the rate of mTICI ≥ 2c after first-pass effect (FPE). Additional efficacy endpoints were the rates of mTICI ≥ 2b after first pass (modified FPE (mFPE)), last pass with study device defined as frontline technical success, and after all passes including rescue therapy. The primary safety endpoints included symptomatic ICH (sICH) within 24 h post-procedure.

RESULTS

Between February 2022 to December 2022, 80 subjects were consented and enrolled in the study (n = 40 treatment arm, n = 40 control arm). In the intent to treat (ITT) population, mean age was 67.8 ± 11.5 years; 19 (47.5%) were male. Median NIHSS score was 16 (IQR: 13-22). Median ASPECTS score was 9 (IQR: 8-10). The rate of mTICI ≥ 2c after first pass was 53.9% in ITT population (60.0% in per-protocol population) versus 38.5% in the corresponding control population. Functional independence (mRS 0-2) at 90 days was achieved in 61.1% (22/36) in the RapidPulseTM arm and 52.8% (19/36) in the control arm. In the RapidPulseTM arm, no sICH within 24 h and no device-related morbidity or mortality occurred.

CONCLUSION

Preliminary data suggests RapidPulseTM Aspiration System is highly effective and safe for recanalization of large vessel occlusions.

Clinical applications of ultrasound in neurosurgery and neurocritical care: A narrative review

Ultrasonography (USG) has become an invaluable tool in the assessment of neurocritical patients in the operating theaters and critical care units. Due to its easy availability, reliability, safety, and repeatability, neuro-intensivists and neuro-anesthesiologists utilize USG to make a diagnosis, assess prognosis, and decide upon treatment. In neurocritical care units, USG has myriad indications for use, both systemic and neurologic. The neurological indications include the assessment of stroke, vasospasm, traumatic brain injury, brain death, acute brain damage, optic nerve sheath diameter, and pupillary reflexes to name a few. The systemic indications range from assessment of cardio-pulmonary function and intravascular volume status to detection of deep venous thromboses, vocal cord assessment in intubated patients, placement of central venous catheters, and percutaneous tracheostomy. In this narrative review, we iterate the clinical applications of USG in neuroanesthesia and neurocritical care, which we penned after searching relevant databases in PubMed, Medline, Ovid, and Google Scholar by using terms such as ‘applications of transcranial Doppler’, ‘optic nerve sheath diameter’, ‘USG applications in the critical care unit’, and so on. Our search database includes several research papers, neurocritical care books, review articles, and scientific databases. This article reviews various applications of USG in neuroanesthesia, neurosurgery, and neurocritical care.

Non-colloid-cyst primary brain tumors: A systematic review of unexpected fatality

OBJECTIVE

Primary brain tumors have the potential to present a substantial health hazard, ultimately resulting in unforeseen fatalities. Despite the enhanced comprehension of many diseases, the precise prediction of disease progression continues to pose a significant challenge. The objective of this study is to investigate cases of unexpected mortality resulting from primary brain tumors and analyze the variables that contribute to such occurrences.

METHODS

This systematic review explores research on individuals diagnosed with primary brain tumors who experienced unexpected deaths. It uses PRISMA standards and searches PubMed, Google Scholar, and Scopus. Variables considered include age, gender, symptoms, tumor type, WHO grade, postmortem findings, time of death - time taken from first medical presentation or hospital admission to death, comorbidity, and risk factors.

RESULTS

This study examined 46 studies to analyze patient-level data from 76 individuals with unexpected deaths attributed to intracranial lesions, deliberately excluding colloid cysts. The cohort's age distribution showed an average age of 37 years, with no significant gender preference. Headache was the most common initial symptom. Astrocytomas, meningiomas, and glioblastoma were the most common lesions, while the frontal lobe, temporal lobe, and cerebellum were common locations. Meningiomas and astrocytomas showed faster deaths within the first hour of hospital admission.

CONCLUSION

The etiology of unforeseen fatalities resulting from cerebral tumors elucidates an intricate and varied phenomenon. Although unexpected deaths account for a very tiny proportion of total fatalities, it is probable that their actual occurrence is underestimated as a result of underreporting and misdiagnosis.

Key CT markers for predicting haemorrhagic transformation after ischaemic stroke: a prospective cohort study in China

OBJECTIVES

Limited studies have systematically addressed the CT markers of predicting haemorrhagic transformation (HT). We aimed to (1) investigate the predictive ability of the imaging factors on multimodal CT for HT and (2) identify the key CT markers that can accurately predict HT while maintaining easy and rapid assessment in the early stage of stroke.

DESIGN AND SETTING

This was a prospective cohort study conducted in a tertiary hospital in Southwest China.

PARTICIPANTS

Patients with ischaemic stroke admitted within 24 hours after onset were included.

OUTCOME MEASURES

The primary outcome was measured as the overall HT. The secondary outcomes were the presence of parenchymal haematoma, symptomatic HT and spontaneous HT.

RESULTS

A total of 763 patients were included. The early hypodensity >1/3 of the middle cerebral artery (MCA) territory, Alberta Stroke Programme Early CT Score≤7, midline shift, hyperdense middle cerebral artery sign (HMCAS), poor collateral circulation, infarct core and penumbra was independently associated with the increased risk of HT (all p < 0.05). The sensitivity of midline shift for predicting HT was only 3.5%, whereas its specificity was 99.8%. The combination of the early hypodensity >1/3 of the MCA territory, midline shift and HMCAS showed a good predictive performance for HT (area under the curve 0.80, 95% CI 0.75 to 0.84).

CONCLUSIONS

Seven imaging factors on multimodal CT were independently associated with HT. The high specificity of midline shift suggests the need to consider it as an imaging indicator when assessing the risk of HT. The early hypodensity >1/3 of the MCA territory, midline shift and HMCAS was identified as the key CT markers for the early prediction of HT. The coexistence of the three key factors might be a valuable index for identifying individuals at high bleeding risk and guiding further treatments.

Factors for predicting recurrence after burr hole drainage for chronic subdural hematoma: a retrospective study

Chronic subdural hematoma (SDH) is a common disease in the neurosurgical field, and hematoma drainage through burr hole trephination has been widely considered the optimal treatment for SDH. Despite numerous investigations aimed at predicting recurrence rates and associated factors, studies have demonstrated inconsistent results. In this study, we aimed to comprehensively determine the predictive factors of chronic SDH recurrence in surgically treated patients. We retrospectively evaluated 578 consecutive patients who underwent single burr hole surgery for chronic SDH at our institute between January 2008 and December 2021. Various clinical and radiological factors in patients with and without recurrence were compared using univariate and multivariate logistic regression analyses. A total of 438 patients (531 hemispheres) were analyzed. Fifty-four (10.17%) of the 531 hemispheres had recurrence of chronic SDH within 6 months. Male sex (adjusted odds ratio (aOR) = 3.48; 95% confidence interval (CI), 1.42-8.49), bilateral hematomas (aOR = 2.14; 95% CI, 1.05-4.35), laminar hematoma type (aOR = 2.87; 95% CI, 1.23-6.71), > 30-cm3 volume of postoperative residual hematoma (aOR = 2.99; 95% CI, 1.01-8.83), and preoperative blood glucose level of ≥ 150 mg/dL (aOR = 2.11; 95% CI, 1.10-4.05) were identified as independent factors associated with recurrence in multivariate logistic regression analysis. The present study revealed that male patients and those who had bilateral hematomas, laminar hematoma type, a large volume of hematoma after surgery, and a high preoperative blood glucose level had a higher probability of experiencing recurrent chronic SDH. We recommend close monitoring of patients 6 months postoperatively to detect subsequent chronic SDH recurrence.

Relay learning: a physically secure framework for clinical multi-site deep learning

Big data serves as the cornerstone for constructing real-world deep learning systems across various domains. In medicine and healthcare, a single clinical site lacks sufficient data, thus necessitating the involvement of multiple sites. Unfortunately, concerns regarding data security and privacy hinder the sharing and reuse of data across sites. Existing approaches to multi-site clinical learning heavily depend on the security of the network firewall and system implementation. To address this issue, we propose Relay Learning, a secure deep-learning framework that physically isolates clinical data from external intruders while still leveraging the benefits of multi-site big data. We demonstrate the efficacy of Relay Learning in three medical tasks of different diseases and anatomical structures, including structure segmentation of retina fundus, mediastinum tumors diagnosis, and brain midline localization. We evaluate Relay Learning by comparing its performance to alternative solutions through multi-site validation and external validation. Incorporating a total of 41,038 medical images from 21 medical hosts, including 7 external hosts, with non-uniform distributions, we observe significant performance improvements with Relay Learning across all three tasks. Specifically, it achieves an average performance increase of 44.4%, 24.2%, and 36.7% for retinal fundus segmentation, mediastinum tumor diagnosis, and brain midline localization, respectively. Remarkably, Relay Learning even outperforms central learning on external test sets. In the meanwhile, Relay Learning keeps data sovereignty locally without cross-site network connections. We anticipate that Relay Learning will revolutionize clinical multi-site collaboration and reshape the landscape of healthcare in the future.

Net benefit of diagnostic tests for multistate diseases: an indicator variables approach

A limitation of the common measures of diagnostic test performance, such as sensitivity and specificity, is that they do not consider the relative importance of false negative and false positive test results, which are likely to have different clinical consequences. Therefore, the use of classification or prediction measures alone to compare diagnostic tests or biomarkers can be inconclusive for clinicians. Comparing tests on net benefit can be more conclusive because clinical consequences of misdiagnoses are considered. The literature suggested evaluating the binary diagnostic tests based on net benefit, but did not consider diagnostic tests that classify more than two disease states, e.g., stroke subtype (large-artery atherosclerosis, cardioembolism, small-vessel occlusion, stroke of other determined etiology, stroke of undetermined etiology), skin lesion subtype, breast cancer subtypes (benign, mass, calcification, architectural distortion, etc.), METAVIR liver fibrosis state (F0- F4), histopathological classification of cervical intraepithelial neoplasia (CIN), prostate Gleason grade, brain injury (intracranial hemorrhage, mass effect, midline shift, cranial fracture) . Other diseases have more than two stages, such as Alzheimer's disease (dementia due to Alzheimer's disease, mild cognitive disability (MCI) due to Alzheimer's disease, and preclinical presymptomatics due to Alzheimer's disease). In diseases with more than two states, the benefits and risks may vary between states. This paper extends the net-benefit approach of evaluating binary diagnostic tests to multi-state clinical conditions to rule-in or rule-out a clinical condition based on adverse consequences of work-up delay (due to false negative test result) and unnecessary workup (due to false positive test result). We demonstrate our approach with numerical examples and real data.

Standardized measurement of mid-surface shift of brain based on deep Hough transform

The measurement of mid-surface shift (MSS), the geometric displacement between the actual mid-surface and the ideal midsagittal plane (iMSP), is of great significance for accurate diagnosis, treatment and prognosis of patients with intracranial hemorrhage (ICH). Most previous studies are subject to inherent inaccuracy on account of calculating midline shift (MLS) based on 2D slices and ignoring pathological conditions. In this study, we propose a novel standardized measurement model to quantify the distance and the overall volume of mid-surface shift (MSS-D, MSS-V). Our work has four highlights. First, we develop an end-to-end network architecture with multiple sub-tasks including the actual mid-surface segmentation, hematoma segmentation and iMSP detection, which significantly improves the efficiency and accuracy of MSS measurement by taking advantage of the common properties among tasks. Second, an efficient iMSP detection scheme is proposed based on the differentiable deep Hough transform (DHT), which converts and simplifies the plane detection problem in the image space into a keypoint detection problem in the Hough space. Third, we devise a sparse DHT strategy and a weighted least square (WLS) method to increase the sparsity of features, improving inference speed and greatly reducing computation cost. Fourth, we design a joint loss function to comprehensively consider the correlation of features between multi-tasks and multi-domains. Extensive validation on our large in-house dataset (519 patients) and the public CQ500 dataset (491 patients), demonstrates the superiority of our method over the state-of-the-art methods.

Functional Outcomes and Mortality in Patients With Intracerebral Hemorrhage After Intensive Medical and Surgical Support

BACKGROUND AND OBJECTIVES

Despite decades of increasingly sophisticated neurocritical care, patient outcomes after spontaneous intracerebral hemorrhage (ICH) remain dismal. Whether this reflects therapeutic nihilism or the effects of the primary injury has been questioned. In this contemporary cohort, we determined the 30- and 90-day mortality, cause-specific mortality, functional outcome, and the effect of surgical intervention in a culture of aggressive medical and surgical support.

METHODS

This was a retrospective cohort study of consecutive adult patients with spontaneous ICH admitted to a tertiary neurocritical care unit. Patients with secondary ICH and those subject to limitation of care before 72 hours were excluded. For each ICH score, mortality at 30- and 90-days, and the modified Rankin Scale (mRS) within 1-year were examined. The effect of craniotomy/craniectomy ± hematoma evacuation on the outcome of supratentorial ICH was determined using propensity score matching. Median patient follow-up after discharge was 2.2 (interquartile range [IQR] 0.4-4.4) years.

RESULTS

Among 319 patients with spontaneous ICH (median age was 69 [IQR 60-77] years, 60% male), 30- and 90-day mortality were 16% and 22%, respectively, and unfavorable functional outcome (mRS score 4-6) was 50% at a median 3.1 months after ICH. Admission predictors of mortality mirrored those of the original ICH score. Unfavorable outcomes for ICH scores 3 and 4 were 73% and 86%, respectively. The most common adjudicated primary causes of mortality were direct effect or progression of ICH (54%), refractory cerebral edema (21%), and medical complications (11%). In matched analyses, lifesaving surgery for supratentorial ICH did not significantly alter mortality or unfavorable functional outcome in patients overall. In subgroup analyses restricted to (1) surgery with hematoma evacuation and (2) ICH score 3 and 4 patients, the odds of 30-day mortality were reduced by 71% (odds ratio [OR] 0.29, 95% CI 0.09-0.9, p = 0.032) and 80% (OR 0.2, 95% CI 0.04-0.91, p = 0.038), respectively, but no difference was observed for 90-day mortality or unfavorable functional outcome.

DISCUSSION

This study demonstrates that poor outcomes after ICH prevail despite aggressive treatment. Unfavorable outcomes appear related to direct effects of the primary injury and not to premature care limitations. Lifesaving surgery for supratentorial lesions delayed mortality but did not alter functional outcomes.

AI-Based Decision Support System for Traumatic Brain Injury: A Survey

Traumatic brain injury (TBI) is one of the major causes of disability and mortality worldwide. Rapid and precise clinical assessment and decision-making are essential to improve the outcome and the resulting complications. Due to the size and complexity of the data analyzed in TBI cases, computer-aided data processing, analysis, and decision support systems could play an important role. However, developing such systems is challenging due to the heterogeneity of symptoms, varying data quality caused by different spatio-temporal resolutions, and the inherent noise associated with image and signal acquisition. The purpose of this article is to review current advances in developing artificial intelligence-based decision support systems for the diagnosis, severity assessment, and long-term prognosis of TBI complications.

Evaluation of extent vs velocity of cortical venous filing in stroke outcome after endovascular thrombectomy

PURPOSE

Abnormal venous drainage may affect the prognosis of patients undergoing endovascular reperfusion therapy (ERT). Herein, time-resolved dynamic computed tomography arteriography (dCTA) was applied to evaluate the relationship between the velocity and extent of cortical venous filling (CVF), collateral status and outcomes.

METHODS

Thirty-five consecutive patients with acute anterior circulation occlusion who underwent ERT within 24 h of onset and successfully recanalized were enrolled. All patients underwent dCTA before ERT. Slow first or end of CVF was considered to occur when the time point of CVF appearance or disappearance on the affected side occurred after than that on the healthy side, whereas an equal CVF, a CVF reduced by ≤ 50%, or by > 50% on the affected side, were considered good, intermediate, and poor CVF extent, respectively.

RESULTS

Slow first CVF (29 patients, 82.8%), slow end of CVF (29, 85.7%), and intermediate extent of CVF (7, 20.0%) were not associated with collateral status or outcomes. Poor extent of CVF (6, 17.1%) was associated with poor collateral status, higher proportion of midline shift, larger final infarct volume, higher modified Rankin Scale (mRS) score at discharge, and higher proportion of in-hospital mortality. All patients with transtentorial herniation had poor extent of CVF, and those with poor CVF extent had an mRS score ≥ 3 at discharge.

CONCLUSION

Poor CVF extent, as assessed by dCTA, is a more accurate and specific marker than slow CVF to identify patients at high risk for poor outcomes after ERT.

Neuromonitoring in Critically Ill Patients

OBJECTIVES

Critically ill patients are at high risk of acute brain injury. Bedside multimodality neuromonitoring techniques can provide a direct assessment of physiologic interactions between systemic derangements and intracranial processes and offer the potential for early detection of neurologic deterioration before clinically manifest signs occur. Neuromonitoring provides measurable parameters of new or evolving brain injury that can be used as a target for investigating various therapeutic interventions, monitoring treatment responses, and testing clinical paradigms that could reduce secondary brain injury and improve clinical outcomes. Further investigations may also reveal neuromonitoring markers that can assist in neuroprognostication. We provide an up-to-date summary of clinical applications, risks, benefits, and challenges of various invasive and noninvasive neuromonitoring modalities.

DATA SOURCES

English articles were retrieved using pertinent search terms related to invasive and noninvasive neuromonitoring techniques in PubMed and CINAHL.

STUDY SELECTION

Original research, review articles, commentaries, and guidelines.

DATA EXTRACTION

Syntheses of data retrieved from relevant publications are summarized into a narrative review.

DATA SYNTHESIS

A cascade of cerebral and systemic pathophysiological processes can compound neuronal damage in critically ill patients. Numerous neuromonitoring modalities and their clinical applications have been investigated in critically ill patients that monitor a range of neurologic physiologic processes, including clinical neurologic assessments, electrophysiology tests, cerebral blood flow, substrate delivery, substrate utilization, and cellular metabolism. Most studies in neuromonitoring have focused on traumatic brain injury, with a paucity of data on other clinical types of acute brain injury. We provide a concise summary of the most commonly used invasive and noninvasive neuromonitoring techniques, their associated risks, their bedside clinical application, and the implications of common findings to guide evaluation and management of critically ill patients.

CONCLUSIONS

Neuromonitoring techniques provide an essential tool to facilitate early detection and treatment of acute brain injury in critical care. Awareness of the nuances of their use and clinical applications can empower the intensive care team with tools to potentially reduce the burden of neurologic morbidity in critically ill patients.

Novel CT-based parameters assessing relative cross-sectional area to guide surgical management and predict clinical outcomes in patients with acute subdural hematoma

INTRODUCTION

Acute subdural hematoma (aSDH) is one of the most devastating entities secondary to traumatic brain injury (TBI). Even though radiological computed tomography (CT) findings, such as hematoma thickness (HT), midline shift (MLS), and MLS/HT ratio, have an important prognostic role, they suffer from important drawbacks. We hypothesized that relative cross-sectional area (rCSA) of specific brain regions would provide valuable information about brain compression and swelling, thus being a key determining factor governing the clinical course.

METHODS

We performed an 8-year retrospective analysis of patients with moderate to severe TBI with surgically evacuated, isolated, unilateral aSDH. We investigated the influence of aSDH rCSA and ipsilateral hemisphere rCSA along the supratentorial region on the subsequent operative technique employed for aSDH evacuation and patient's clinical outcomes (early death and Glasgow Outcome Scale [GOS] at discharge and after 1-year follow-up). Different conventional radiological variables were also assessed.

RESULTS

The study included 39 patients. Lower HT, MLS, hematoma volume, and aSDH rCSA showed a significant association with decompressive craniectomy (DC) procedure. Conversely, higher ipsilateral hemisphere rCSA along the dorso-ventral axis and, specifically, ipsilateral hemisphere rCSA at the high convexity level were predictors for DC. CT segmentation analysis exhibited a modest relationship with early death, which was limited to the basal supratentorial subregion, but could not predict long-term outcome.

CONCLUSION

rCSA is an objectifiable and reliable radiologic parameter available on admission CT that might provide valuable information to optimize surgical treatment.

Multiparametric Quantitative Imaging Biomarkers for Phenotype Classification: A Framework for Development and Validation

This manuscript is the third in a five-part series related to statistical assessment methodology for technical performance of multi-parametric quantitative imaging biomarkers (mp-QIBs). We outline approaches and statistical methodologies for developing and evaluating a phenotype classification model from a set of multiparametric QIBs. We then describe validation studies of the classifier for precision, diagnostic accuracy, and interchangeability with a comparator classifier. We follow with an end-to-end real-world example of development and validation of a classifier for atherosclerotic plaque phenotypes. We consider diagnostic accuracy and interchangeability to be clinically meaningful claims for a phenotype classification model informed by mp-QIB inputs, aiming to provide tools to demonstrate agreement between imaging-derived characteristics and clinically established phenotypes. Understanding that we are working in an evolving field, we close our manuscript with an acknowledgement of existing challenges and a discussion of where additional work is needed. In particular, we discuss the challenges involved with technical performance and analytical validation of mp-QIBs. We intend for this manuscript to further advance the robust and promising science of multiparametric biomarker development.

Good outcome associated with blood-brain barrier disruption and lower blood pressure after endovascular therapy

OBJECTIVES

To evaluate the association between post-endovascular thrombectomy (EVT) blood-brain barrier (BBB) disruption on MRI or CT and average systolic blood pressure (SBP) with favorable 90-day functional outcome. Observational studies have found elevated SBP associated with worse outcomes post-EVT, while recent randomized trials found no difference in targeted BP reduction. There may be a subgroup of patients who benefit from targeted BP reduction post-EVT.

METHODS

This is a single-center study of 1) anterior large vessel occlusion stroke patients treated with EVT from 2015 to 2021, 2) achieved mTICI grade 2b or 3. Hyperintense acute reperfusion marker (HARM), hemorrhagic transformation (HT), and midline shift at 3 h post-EVT and 24 h imaging were assessed independently by multiple raters. Binary logistic regression models were used to determine the association of post-EVT SBP with outcomes. BBB disruption was defined as HT or HARM on 3h post-EVT imaging.

RESULTS

Of 103 patients, those with SBP 100-129 versus SBP 130-160 found no significant difference in favorable 90-day outcome (64% vs. 46%, OR 2.11, 95% CI 0.78-5.76, p=0.143). However, among 71 patients with BBB disruption, a significant difference in favorable outcome of 64% in SBP 100-129 vs. 39% in SBP 130-160 group (OR 5.93, 95% CI 1.50-23.45, p=0.011) was found. There was no difference in symptomatic ICH, 90-day mortality, midline shift (≥5 mm), and hemicraniectomy, between BP or BBB groups.

CONCLUSIONS

BBB disruption on 3h post-EVT imaging and lower SBP was associated with favorable outcome. This imaging finding may guide targeted BP therapy and suggests need for a randomized control trial.

Poor Internal Jugular Venous Outflow Is Associated with Poor Cortical Venous Outflow and Outcomes after Successful Endovascular Reperfusion Therapy

Many patients show poor outcomes following endovascular reperfusion therapy (ERT), and poor cortical venous outflow is a risk factor for these poor outcomes. We investigated the association between the outflow of the internal jugular vein (IJV) and baseline cortical venous outflow and the outcomes after ERT. We retrospectively enrolled 78 patients diagnosed with an acute anterior circulation stroke and successful ERT. Poor IJV outflow on the affected side was defined as stenosis ≥50% or occlusion of ipsilateral IJV, and poor outflow of bilateral IJVs was defined as stenosis ≥50% or occlusion of both IJVs. Poor cortical venous outflow was defined as a cortical vein opacification score (COVES) of 0 on admission. Multivariate analysis showed that poor outflow of IJV on the affected side was an independent predictor for hemorrhagic transformation. The poor outflow of bilateral IJVs was an independent risk factor for poor clinical outcomes. These patients also had numerical trends of a higher incidence of symptomatic intracranial hemorrhage, midline shift >10 mm, and in-hospital mortality; however, statistical significance was not observed. Additionally, poor IJV outflow was an independent determinant of poor cortical venous outflow. For acute large vessel occlusion patients, poor IJV outflow is associated with poor baseline cortical venous outflow and outcomes after successful ERT.

Effects of Hyperferritinemia on Functional Outcome in Acute Ischemic Stroke Patients with Admission Hyperglycemia

INTRODUCTION

Hyperferritinemia, presented as elevated serum ferritin level, is an indicator of high iron status which plays roles in secondary brain injury after acute ischemic stroke (AIS). However, the effects of hyperferritinemia and poor outcomes remain uncertain. Additionally, admission hyperglycemia quite frequently accompanies AIS patients, which is associated with unfavorable outcome. Thus, we aimed to investigate the effects of hyperferritinemia on 3-month and 1-year functional outcomes in AIS patients and especially those with admission hyperglycemia.

METHODS

AIS patients within 24 h of onset were enrolled at West China Hospital from October 2016 to December 2019. Serum ferritin and blood glucose levels were tested on admission. Poor functional outcome at 3 months and 1 year was defined as modified Rankin Scale score ≥3. Multivariable analysis was used to investigate the associations between hyperferritinemia and 3-month and 1-year outcomes. Subgroup analysis was performed in patients with and without hyperglycemia.

RESULTS

Of 723 patients (mean age 68.11 years, 60.6% males) finally included, 347 (48.0%) had hyperferritinemia. The incidence of poor outcome was 45.2% at 3 months and 41.2% at 1 year. Patients with hyperferritinemia had a higher frequency of poor 3-month outcome (51.8% vs. 39.2%, p = 0.001) and poor 1-year outcome (46.8% vs. 36.1%, p = 0.004). In all AIS patients, hyperferritinemia was not independently associated with poor functional outcome at 3 months or 1 year after adjusting for confounders (all p > 0.05). In AIS patients with hyperglycemia, hyperferritinemia was an independent factor correlated with poor 3-month outcome (OR = 1.711, 95% CI 1.093-2.681, p = 0.019) but not with poor 1-year outcome (p > 0.05).

CONCLUSIONS

High iron status, presented as hyperferritinemia, is associated with poor 3-month functional outcome in AIS patients with hyperglycemia. Evaluating serum ferritin level may be conducive to assess the risk of short-term poor outcome in AIS patients with hyperglycemia. Further studies will be required to confirm our findings.

Radiologic Evaluation Criteria for Chronic Subdural Hematomas: Recommendations for Clinical Trials

Embolization of the middle meningeal artery has gained substantial interest as a therapy for chronic subdural hematomas. For the results of the currently running chronic subdural hematoma trials to inform clinical practice, sufficient accuracy and matching definitions are necessary. We summarized the current practice in chronic subdural hematoma evaluation and derived suggestions on reporting standards using the {Nested} Knowledge AutoLit living review platform. On the basis of the most commonly reported data elements, we suggested a set of standardized image-based study end points for chronic subdural hematoma evaluation for future trials. The measurement methods and reporting standards as proposed in this article have been derived from published best practices and are endorsed by the European Society of Minimally Invasive Neurological Therapy's research committee. The standardization of radiologic outcome measures and measurement techniques in chronic subdural hematoma embolization trials would increase the impact and implication of each trial as well as facilitate data pooling for increased statistical power and, therefore, translation to clinical practice.

Subgaleal Effusion and Brain Midline Shift After Cranioplasty: A Retrospective Study Between Polyetheretherketone Cranioplasty and Titanium Cranioplasty After Decompressive Craniectomy

Cranioplasty with polyetheretherketone (PEEK) has recently shown better cerebral protection performance, improved brain function, and aesthetic contour compared with titanium mesh. However, whether patients undergoing PEEK cranioplasty tend to develop subgaleal effusions remains elusive. This retrospective study included patients who underwent cranioplasty with PEEK implants or titanium mesh after decompressive craniectomy between July 2017 and July 2020. Patient information, including general information, location, size of the defect, subgaleal depth, and brain midline shift was collected and statistically analyzed. There were 130 cases of cranioplasty, including 35 with PEEK implants and 95 with a titanium mesh. Patients who underwent cranioplasty with a PEEK implant had a higher subgaleal effusion rate than those who underwent cranioplasty with titanium mesh (85.71% vs. 53.68%, P < 0.001), while a midline shift >5 mm was more frequently observed in the PEEK group than in the titanium group (20% vs. 6.3%, P = 0.021). The PEEK material was the only factor associated with subgaleal effusion after cranioplasty (OR 5.589, P = 0.002). Logistic regression analysis further showed that age was a protective factor against midline shift in the PEEK cranioplasty group (OR 0.837, P = 0.029). Patients who underwent cranioplasty with PEEK implants were more likely to develop severe subgaleal effusion and significant brain midline shifts than those with titanium mesh implants.

Association Between Post-procedure Cerebral Blood Flow Velocity and Severity of Brain Edema in Acute Ischemic Stroke With Early Endovascular Therapy

Objectives

We aimed to investigate the association between post-procedure cerebral blood flow velocity (CBFV) and severity of brain edema in patients with acute ischemic stroke (AIS) who received early endovascular therapy (EVT).

Methods

We retrospectively included patients with AIS who received EVT within 24 h of onset between February 2016 and November 2021. Post-procedure CBFV of the middle cerebral artery was measured in the affected and the contralateral hemispheres using transcranial Doppler ultrasound. The severity of brain edema was measured using the three-level cerebral edema grading from the Safe Implementation of Thrombolysis in Stroke-Monitoring Study, with grades 2–3 indicating severe brain edema. The Association between CBFV parameters and severity of brain edema was analyzed.

Results

A total of 101 patients (mean age 64.2 years, 65.3% male) were included, of whom 56.3% (57/101) suffered brain edema [grade 1, 23 (22.8%); grade 2, 10 (9.9%); and grade 3, 24 (23.8%)]. Compared to patients with non-severe brain edema, patients with severe brain edema had lower affected/contralateral ratios of systolic CBFV (median 1 vs. 1.2, P = 0.020) and mean CBFV (median 0.9 vs. 1.3, P = 0.029). Multivariate logistic regression showed that severe brain edema was independently associated with affected/contralateral ratios of systolic CBFV [odds ratio (OR) = 0.289, 95% confidence interval (CI): 0.069–0.861, P = 0.028] and mean CBFV (OR = 0.278, 95% CI: 0.084–0.914, P = 0.035) after adjusting for potential confounders.

Conclusion

Post-procedure affected/contralateral ratio of CBFV may be a promising predictor of brain edema severity in patients with AIS who received early EVT.

Midline Brain Shift After Hemispheric Surgery: Natural History, Clinical Significance, and Association With Cerebrospinal Fluid Diversion

BACKGROUND

Hemispherectomy and its modern variants are effective surgical treatments for medically intractable unihemispheric epilepsy. Although some complications such as posthemispherectomy hydrocephalus are well documented, midline brain shift (MLBS) after hemispheric surgery has only been described anecdotally and never formally studied.

OBJECTIVE

To assess the natural history and clinical relevance of MLBS and determine whether cerebrospinal fluid (CSF) shunting of the ipsilateral surgical cavity exacerbates MLBS posthemispheric surgery.

METHODS

A retrospective review of consecutive pediatric patients who underwent hemispheric surgery for intractable epilepsy and at least 6 months of follow-up at UCLA between 1994 and 2018 was performed. Patients were grouped by MLBS severity, shunt placement, valve type, and valve opening pressure (VOP). MLBS was evaluated using the paired samples t-test and analysis of covariance adjusting for follow-up time and baseline postoperative MLBS.

RESULTS

Seventy patients were analyzed, of which 23 (33%) required CSF shunt placement in the ipsilateral surgical cavity for posthemispherectomy hydrocephalus. MLBS increased between first and last follow-up for nonshunted (5.3 ± 4.9-9.7 ± 6.6 mm, P < .001) and shunted (6.6 ± 3.5-16.3 ± 9.4 mm, P < .001) patients. MLBS progression was greater in shunted patients (P = .001). Shunts with higher VOPs did not increase MLBS relative to nonshunted patients (P = .834), whereas MLBS increased with lower VOPs (P = .001). Severe MLBS was associated with debilitating headaches (P = .048).

CONCLUSION

Patients undergoing hemispheric surgery often develop postoperative MLBS, ie, exacerbated by CSF shunting of the ipsilateral surgical cavity, specifically when using lower VOP settings. MLBS exacerbation may be related to overshunting. Severe MLBS is associated with debilitating headaches.

Quantification of Tissue Compression Identifies High-Grade Glioma Patients with Reduced Survival

The compression of peritumoral healthy tissue in brain tumor patients is considered a major cause of the life-threatening neurologic symptoms. Although significant deformations caused by the tumor growth can be observed radiologically, the quantification of minor tissue deformations have not been widely investigated. In this study, we propose a method to quantify subtle peritumoral deformations. A total of 127 MRI longitudinal studies from 23 patients with high-grade glioma were included. We estimate longitudinal displacement fields based on a symmetric normalization algorithm and we propose four biomarkers. We assess the interpatient and intrapatient association between proposed biomarkers and the survival based on Cox analyses, and the potential of the biomarkers to stratify patients according to their survival based on Kaplan−Meier analysis. Biomarkers show a significant intrapatient association with survival (p < 0.05); however, only compression biomarkers show the ability to stratify patients between those with higher and lower overall survival (AUC = 0.83, HR = 6.30, p < 0.05 for CompCH). The compression biomarkers present three times higher Hazard Ratios than those representing only displacement. Our study provides a robust and automated method for quantifying and delineating compression in the peritumoral area. Based on the proposed methodology, we found an association between lower compression in the peritumoral area and good prognosis in high-grade glial tumors.

A Robust, Fully Automatic Detection Method and Calculation Technique of Midline Shift in Intracranial Hemorrhage and Its Clinical Application

A midline shift (MLS) is an important clinical indicator for intracranial hemorrhage. In this study, we proposed a robust, fully automatic neural network-based model for the detection of MLS and compared it with MLSs drawn by clinicians; we also evaluated the clinical applications of the fully automatic model. We recruited 300 consecutive non-contrast CT scans consisting of 7269 slices in this study. Six different types of hemorrhage were included. The automatic detection of MLS was based on modified Keypoint R-CNN with keypoint detection followed by training on the ResNet-FPN-50 backbone. The results were further compared with manually drawn outcomes and manually defined keypoint calculations. Clinical parameters, including Glasgow coma scale (GCS), Glasgow outcome scale (GOS), and 30-day mortality, were also analyzed. The mean absolute error for the automatic detection of an MLS was 0.936 mm compared with the ground truth. The interclass correlation was 0.9899 between the automatic method and MLS drawn by different clinicians. There was high sensitivity and specificity in the detection of MLS at 2 mm (91.7%, 80%) and 5 mm (87.5%, 96.7%) and MLSs greater than 10 mm (85.7%, 97.7%). MLS showed a significant association with initial poor GCS and GCS on day 7 and was inversely correlated with poor 30-day GOS (p < 0.001). In conclusion, automatic detection and calculation of MLS can provide an accurate, robust method for MLS measurement that is clinically comparable to the manually drawn method.

Bedside detection of intracranial midline shift using portable magnetic resonance imaging

Neuroimaging is crucial for assessing mass effect in brain-injured patients. Transport to an imaging suite, however, is challenging for critically ill patients. We evaluated the use of a low magnetic field, portable MRI (pMRI) for assessing midline shift (MLS). In this observational study, 0.064 T pMRI exams were performed on stroke patients admitted to the neuroscience intensive care unit at Yale New Haven Hospital. Dichotomous (present or absent) and continuous MLS measurements were obtained on pMRI exams and locally available and accessible standard-of-care imaging exams (CT or MRI). We evaluated the agreement between pMRI and standard-of-care measurements. Additionally, we assessed the relationship between pMRI-based MLS and functional outcome (modified Rankin Scale). A total of 102 patients were included in the final study (48 ischemic stroke; 54 intracranial hemorrhage). There was significant concordance between pMRI and standard-of-care measurements (dichotomous, κ = 0.87; continuous, ICC = 0.94). Low-field pMRI identified MLS with a sensitivity of 0.93 and specificity of 0.96. Moreover, pMRI MLS assessments predicted poor clinical outcome at discharge (dichotomous: adjusted OR 7.98, 95% CI 2.07–40.04, p = 0.005; continuous: adjusted OR 1.59, 95% CI 1.11–2.49, p = 0.021). Low-field pMRI may serve as a valuable bedside tool for detecting mass effect.

Midline Shift in Chronic Subdural Hematoma : Interrater Reliability of Different Measuring Methods and Implications for Standardized Rating in Embolization Trials

OBJECTIVE

Evaluation of chronic subdural hematoma (cSDH) treatment success relies on radiologic measures, in particular hematoma volume, width and midline shift (MLS). Nevertheless, there are no validated standards for MLS measurement in cSDH. Aim of this study was to identify the most reliable measurement location and technique for MLS.

METHODS

Admission CT scans of 57 patients with unilateral cSDH were retrospectively analyzed. Axial slices were evaluated by 4 raters with MLS measurement in 4 locations, foramen of Monro (FM), thalamus (Th), mid-septum pellucidum (SP), maximum overall MLS (max) with 2 different techniques: displacement perpendicular to anatomical (ideal) midline (MLS-M), and displacement relative to the tabula interna in relation to the width of the intracranial space (MLS-T). Intraclass correlation coefficients (ICC) were calculated to assess interrater reliability and agreement of MLS‑M and MLS‑T measurement techniques. Measurements of cSDH volume and width were conducted for further data alignment.

RESULTS

The ICCs between readers were excellent (> 0.9) for all MLS‑M locations and for MLS-T_Th and ML-T_FM. The ICC was higher for MLS‑M than for MLS‑T in all locations. MLS-M_max showed the highest correlation coefficient of 0.78 with cSDH volume. Variance of MLS-M_max was explained in 64% of cases (adj. R squared) by cSDH volume based on a simple linear regression model. An increase of 10 ml cSDH volume resulted in an average increase of 0.8 mm MLS-M_max.

CONCLUSION

The MLS measurement in cSDH patients should be standardized, and due to its high interrater reliability, the MLS‑M technique should be preferred.

Radiological Evaluation Criteria for Chronic Subdural Hematomas : Review of the Literature

BACKGROUND

The methodology of measuring chronic subdural hematoma (cSDH) extent and its effect on intracranial structures is relevant for patient classification and outcome measurements and affects the external validity of cSDH studies. With embolization of the middle meningeal artery (MMA) as a possible treatment of cSDHs, the topic has gained substantial interest. We sought to summarize the heterogeneity of radiologic measurements, specifically in the evaluation of cSDHs based on literature review.

METHODS

In this review, we identified and described the most common radiological methodologies for measurements of cSDH thickness, cSDH volume and of midline shift.

CONCLUSION

There are numerous published methods on how to evaluate cSDH thickness, cSDH volume and midline shift but no common standard. The definition of measurement methods and reporting standards for MMA embolization in cSDH patients and their validation needs to be addressed.

Testing a convolutional neural network-based hippocampal segmentation method in a stroke population

As stroke mortality rates decrease, there has been a surge of effort to study poststroke dementia (PSD) to improve long-term quality of life for stroke survivors. Hippocampal volume may be an important neuroimaging biomarker in poststroke dementia, as it has been associated with many other forms of dementia. However, studying hippocampal volume using MRI requires hippocampal segmentation. Advances in automated segmentation methods have allowed for studying the hippocampus on a large scale, which is important for robust results in the heterogeneous stroke population. However, most of these automated methods use a single atlas-based approach and may fail in the presence of severe structural abnormalities common in stroke. Hippodeep, a new convolutional neural network-based hippocampal segmentation method, does not rely solely on a single atlas-based approach and thus may be better suited for stroke populations. Here, we compared quality control and the accuracy of segmentations generated by Hippodeep and two well-accepted hippocampal segmentation methods on stroke MRIs (FreeSurfer 6.0 whole hippocampus and FreeSurfer 6.0 sum of hippocampal subfields). Quality control was performed using a stringent protocol for visual inspection of the segmentations, and accuracy was measured as volumetric correlation with manual segmentations. Hippodeep performed significantly better than both FreeSurfer methods in terms of quality control. All three automated segmentation methods had good correlation with manual segmentations and no one method was significantly more correlated than the others. Overall, this study suggests that both Hippodeep and FreeSurfer may be useful for hippocampal segmentation in stroke rehabilitation research, but Hippodeep may be more robust to stroke lesion anatomy.

Automated detection of 3D midline shift in spontaneous supratentorial intracerebral haemorrhage with non-contrast computed tomography using deep convolutional neural networks

Deep learning (DL)-based convolutional neural networks facilitate more accurate detection and rapid analysis of MLS. Our objective was to assess the feasibility of applying a DL-based convolutional neural network to non-contrast computed tomography (CT) for automated 2D/3D brain midline shift measurement and outcome prediction after spontaneous intracerebral haemorrhage. In this retrospective study, 140 consecutive patients were referred for CT assessment of sICH from January 2014 to April 2019. The level of consciousness of patients was evaluated using the Glasgow Coma Scale (GCS) score, and the Glasgow Outcome Scale (GOS) score was calculated to classify the outcome. The distance of midline shift (MLS-D) and volume of midline shift (MLS-V) were automatically measured via DL methods. Patients were divided into three groups based on GCS scores: mild degree (GCS score: 13-15), moderate degree (GCS score: 9-12), and severe degree (GCS score: 3-8). Spearman's correlation analysis revealed statistically significant (P<0.01) positive correlation between GCS and MLS-D (r=0.709) and MLS-V (r=0.754). The AUC of MLS-V was slightly larger than that of MLS-D (0.831 vs 0.799, P=0.318) in the midline shifting group. The AUC of MLS-V was significantly larger than that of MLS-D (0.854 vs 0.736, P=0.03) in patients with severe degree GCS scores. The DL-based measurements of both MLS-D and MLS-V enable the assessment of consciousness and the prediction of the outcome of sICH. Compared to MLS-D, MLS-V measurement can better indicate mass effect and predict outcomes, particularly in severe cases.

Association Between Preoperative Midline Shift Growing Rate and Outcomes of Decompressive Craniectomy in Patients with Malignant Middle Cerebral Artery Infarction

BACKGROUND

Whether preoperative midline shift and its growing rate are associated with outcomes of decompressive craniectomy in patients with malignant middle cerebral artery infarction is unknown.

METHODS

We retrospectively included patients: 1) who underwent decompressive craniectomy for malignant middle cerebral artery infarction in West China Hospital from August 2010 to December 2, 2018) who had at least two brain computed tomography scans before decompressive craniectomy. Midline shift was measured on the first and last preoperative computed tomography scans. Midline shift growing rate was calculated by dividing Δmidline shift value using Δ time. The primary outcome was inadequate decompression of the mass effect. Secondary outcomes were 3 month death and unfavorable outcomes.

RESULTS

Sixty-one patients (mean age 53.7 years, 57.4% (35/61) male) were included. Median time from onset to decompressive craniectomy was 51.8 h (interquartile range: 39.7-77.8). Rates of inadequate decompression, 3 month death, 3 month modified Rankin Scale 5-6 and 4-6 were 50.8% (31/61), 50.9% (29/57), 64.9% (37/57) and 84.2% (48/57), respectively. The inadequate decompression group had a higher midline shift growing rate than the adequate decompression group (median: 2.7 mm/8 h vs. 1.4 mm/8 h, P=0.041). No intergroup difference of 3 month outcomes was found in terms of preoperative midline shift growing rate.

CONCLUSION

Higher preoperative midline shift growing rate was associated with inadequate decompression of decompressive craniectomy in patients with malignant middle cerebral artery infarction.

Automated Detection and Screening of Traumatic Brain Injury (TBI) Using Computed Tomography Images: A Comprehensive Review and Future Perspectives

Traumatic brain injury (TBI) occurs due to the disruption in the normal functioning of the brain by sudden external forces. The primary and secondary injuries due to TBI include intracranial hematoma (ICH), raised intracranial pressure (ICP), and midline shift (MLS), which can result in significant lifetime disabilities and death. Hence, early diagnosis of TBI is crucial to improve patient outcome. Computed tomography (CT) is the preferred modality of choice to assess the severity of TBI. However, manual visualization and inspection of hematoma and its complications from CT scans is a highly operator-dependent and time-consuming task, which can lead to an inappropriate or delayed prognosis. The development of computer aided diagnosis (CAD) systems could be helpful for accurate, early management of TBI. In this paper, a systematic review of prevailing CAD systems for the detection of hematoma, raised ICP, and MLS in non-contrast axial CT brain images is presented. We also suggest future research to enhance the performance of CAD for early and accurate TBI diagnosis.

CT Findings and Histological Evaluation of Red Foxes (Vulpes vulpes) with Chronic Head Trauma Injury: A Retrospective Study

Large numbers of wild animals are injured every year in road traffic accidents. Scant data are available for rescued wild carnivores, in particular for red foxes. Cases of foxes with head trauma were retrospectively considered for inclusion in this study. Clinical examination, modified Glasgow coma scale (MGCS), computed tomography (CT) examination, therapy, outcome, and post mortem findings of the brain were investigated. In all foxes, cranial vaults lesion occurred in single (67%) or multiple sites (33%). Midline shift and hydrocephalus were observed in this population. The mean survival was 290 (±176) days. In our study, we performed CT scans on average 260 days after fox rescue, and we speculate that persisting clinical signs could be attributed to TBI. In our study, only two foxes were alive at the time of writing. Other foxes were euthanized due to the severity of the clinical signs. CT scans help diagnose chronic lesions and their effect on prognostic judgment for animals released to wildlife environments.

Exploration of Multiparameter Hematoma 3D Image Analysis for Predicting Outcome After Intracerebral Hemorrhage

BACKGROUND

Rapid diagnosis and proper management of intracerebral hemorrhage (ICH) play a crucial role in the outcome. Prediction of the outcome with a high degree of accuracy based on admission data including imaging information can potentially influence clinical decision-making practice.

METHODS

We conducted a retrospective multicenter study of consecutive ICH patients admitted between 2012-2017. Medical history, admission data, and initial head computed tomography (CT) scan were collected. CT scans were semiautomatically segmented for hematoma volume, hematoma density histograms, and sphericity index (SI). Discharge unfavorable outcomes were defined as death or severe disability (modified Rankin Scores 4-6). We compared (1) hematoma volume alone; (2) multiparameter imaging data including hematoma volume, location, density heterogeneity, SI, and midline shift; and (3) multiparameter imaging data with clinical information available on admission for ICH outcome prediction. Multivariate analysis and predictive modeling were used to determine the significance of hematoma characteristics on the outcome.

RESULTS

We included 430 subjects in this analysis. Models using automated hematoma segmentation showed incremental predictive accuracies for in-hospital mortality using hematoma volume only: area under the curve (AUC): 0.85 [0.76-0.93], multiparameter imaging data (hematoma volume, location, CT density, SI, and midline shift): AUC: 0.91 [0.86-0.97], and multiparameter imaging data plus clinical information on admission (Glasgow Coma Scale (GCS) score and age): AUC: 0.94 [0.89-0.99]. Similarly, severe disability predictive accuracy varied from AUC: 0.84 [0.76-0.93] for volume-only model to AUC: 0.88 [0.80-0.95] for imaging data models and AUC: 0.92 [0.86-0.98] for imaging plus clinical predictors.

CONCLUSIONS

Multiparameter models combining imaging and admission clinical data show high accuracy for predicting discharge unfavorable outcome after ICH.

Quantitative analysis of brain herniation from non-contrast CT images using deep learning

BACKGROUND

Brain herniation is one of the fatal outcomes of increased intracranial pressure (ICP). It is caused due to the presence of hematoma or tumor mass in the brain. Ideal midline (iML) divides the healthy brain into two (right and left) nearly equal hemispheres. In the presence of hematoma, the midline tends to shift from its original position to the contralateral side of the mass and thus develops a deformed midline (dML).

NEW METHOD

In this study, a convolutional neural network (CNN) was used to predict the deformed left and right hemispheres. The proposed algorithm was validated with non-contrast computed tomography (NCCT) of (n = 45) subjects with two types of brain hemorrhages - epidural hemorrhage (EDH): (n = 5) and intra-parenchymal hemorrhage (IPH): (n = 40)).

RESULTS

The method demonstrated excellent potential in automatically predicting MLS with the average errors of 1.29 mm by location, 66.4 mm² by 2D area, and 253.73 mm³ by 3D volume. Estimated MLS could be well correlated with other clinical markers including hematoma volume - R² = 0.86 (EDH); 0.48 (IPH) and a Radiologist-defined severity score (RSS) - R² = 0.62 (EDH); 0.57 (IPH). RSS was found to be even better correlated (R² = 0.98 (EDH); 0.70 (IPH)), hence better predictable by a joint correlation between hematoma volume, midline pixel- or voxel-shift, and minimum distance of (ideal or deformed) midline from the hematoma (boundary or centroid).

CONCLUSION

All these predictors were computed automatically, which highlighted the excellent clinical potential of the proposed automated method in midline shift (MLS) estimation and severity prediction in hematoma decision support systems.

A nomogram for estimating intracranial pressure using acute subdural hematoma thickness and midline shift

Although criteria for surgical treatment of acute subdural hematoma (SDH) have been proposed, interaction exists between SDH, midline shift (MLS), and intracranial pressure (ICP). Based on our half sphere finite-element model (FEM) of the supratentorial brain parenchyma, tools for ICP estimation using SDH thickness (SDHx) and MLS were developed. We performed 60 single load step, structural static analyses, simulating a left-sided SDH compressing the cerebral hemispheres. The Young's modulus was taken as 10,000 Pa. The ICP loads ranged from 10 to 80 mmHg with Poisson's ratios between 0.25 and 0.49. The SDHx and the MLS results were stored in a lookup table. An ICP estimation equation was derived from these data and then was converted into a nomogram. Numerical convergence was achieved in 49 model analyses. Their SDHx ranged from 0.79 to 28.3 mm, and the MLS ranged from 1.5 to 16.9 mm. The estimation formula was log(ICP) = 0.614-0.520 log(SDHx) + 1.584 log(MLS). Good correlations were observed between invasive ICP measurements and those estimated from preoperative SDHx and MLS data on images using our model. These tools can be used to estimate ICP noninvasively, providing additional information for selecting the treatment strategy in patients with SDH.

Effect of Recanalization on Cerebral Edema, Long-Term Outcome, and Quality of Life in Patients with Large Hemispheric Infarctions

OBJECTIVES

Space-occupying cerebral edema is the main cause of mortality and poor functional outcome in patients with large cerebral artery occlusion (LVO). We aimed to determine whether recanalization of LVO would augment cerebral edema volume and the impact on functional outcome and quality of life (QoL).

MATERIALS AND METHODS

Prospectively, 43 patients with large middle cerebral artery territory infarction or NIHSS ≥ 12 on admission were enrolled. The degree of recanalization (partial and complete versus no recanalization) was assessed by computed tomography (CT)-angiography or Duplex ultrasound more than 24 h after symptom onset. Cerebral edema volume was measured on follow up CTs by computer-based planimetry. Mortality, functional outcome (by modified Ranking Scale (mRS) and Barthel Index (BI)) were assessed at discharge and 12 months, and QoL (by SF-36 and EQ-5D-3L) at 12 months.

RESULTS

Mean cerebral edema volume was 333±141 ml without recanalization (n=13, group 1) and 276±140 ml with partial or complete recanalization (n=30, group 2, p= 0.23). There were no significant differences in mortality at discharge (38% versus 23%), at 12 months (58% versus 48%), in functional outcome at discharge (mRS 0-3: 0% both; mRS 4-5: 62% versus 77%) and at 12 months (mRS 0-3: 0% versus 11%; mRS 4-5: 42% versus 41%). The BI improved significantly from discharge to 12 months only in group 2 (p=0.001). Mean physical component score in SF-36 was 25.6±6.4, psychological component score was 41.9±14.1. In the EQ-5D-3L, most patients reported problems with activities of daily living, reduced mobility, and selfcare.

CONCLUSIONS

Recanalization of a large cerebral artery occlusion in the anterior circulation territories is not associated with amplification of post-ischemic cerebral edema but may be correlated with better long-term functional outcome. QoL was low and mainly dependent on physical disability. The association between recanalization, collateral status and development of cerebral edema after LVO and the effect on functional outcome and quality of life should be explored in a larger patient population.

Brain and behaviour in post-acute stroke: Reduction in seeking and posterior cingulate neuronal variability

INTRODUCTION

Stroke is a complex event on both behavioral and neuronal grounds. Recent investigations evidence the central role of subcortical damage on the post-stroke brain and behavior reorganization. We have conducted an exploratory study combining anatomical lesion analysis, functional analysis of resting state fMRI, and behavioral assessment with focus on exploration as represented by SEEKING.

METHOD

24 stroke inpatients were studied immediately after their clinical stabilization post-stroke; neuronal variability in fMRI along with behavioral outcomes were assessed. These outcomes were compared with a control group of 22 healthy subjects.

RESULTS

First, we observed predominant subcortical lesions in our sample with all stroke patients showing subcortical lesions and only some exhibiting additional cortical lesions. Second, we observed significantly reduced neuronal variability in the posterior cingulate cortex (PCC) that did not show any structural damage. Third, our stroke subjects showed reduced SEEKING which was related to reduced PCC neuronal variability in an abnormal way (compared to healthy subjects). This last outcome was assessed by considering the subset of 11 stroke subjects for which fMRI and behavioral outcomes were jointly measured.

CONCLUSIONS

Taken together, our findings suggest that damage in subcortical regions may play a central role in abnormalities in both cortical activity (PCC) and associated behavior of post-stroke reorganization. Accounting for these aspects may have significant implications to optimize multidisciplinary rehabilitation processes, particularly during the early steps of recovery, reducing the impact of stroke on the patient and caregiver quality of life.

Early cranioplasty associated with a lower rate of post-traumatic hydrocephalus after decompressive craniectomy for traumatic brain injury

BACKGROUND

Post-traumatic hydrocephalus (PTH) is one of the primary complications during the course of traumatic brain injury (TBI). The aim of this study was to define factors associated with the development of PTH in patients who underwent unilateral decompressive craniectomy (DC) for TBI.

METHODS

A total of 126 patients, who met the inclusion criteria of the study, were divided into two groups: patients with PTH (n = 25) and patients without PTH (n = 101). Their demographic, clinical, radiological, operative, and postoperative factors, which may be associated with the development of PTH, were compared.

RESULTS

Multivariate logistic regression analysis revealed that cranioplasty performed later than 2 months following DC was significantly associated with the requirement for ventriculoperitoneal shunting due to PTH (p < 0.001). Also, a significant unfavorable outcome rate was observed in patients with PTH at 1-year follow-up according to the Glasgow Outcome Scale-Extended (p = 0.047).

CONCLUSIONS

Our results show that early cranioplasty within 2 months after DC was associated with a lower rate of PTH development after TBI.

Neural Stem Cell Extracellular Vesicles Disrupt Midline Shift Predictive Outcomes in Porcine Ischemic Stroke Model

Magnetic resonance imaging (MRI) is a clinically relevant non-invasive imaging tool commonly utilized to assess stroke progression in real time. This study investigated the utility of MRI as a predictive measure of clinical and functional outcomes when a stroke intervention is withheld or provided, in order to identify biomarkers for stroke functional outcome under these conditions. Fifteen MRI and ninety functional parameters were measured in a middle cerebral artery occlusion (MCAO) porcine ischemic stroke model. Multiparametric analysis of correlations between MRI measurements and functional outcome was conducted. Acute axial and coronal midline shift (MLS) at 24 h post-stroke were associated with decreased survival and recovery measured by modified Rankin scale (mRS) and were significantly correlated with 52 measured acute (day 1 post) and chronic (day 84 post) gait and behavior impairments in non-treated stroked animals. These results suggest that MLS may be an important non-invasive biomarker that can be used to predict patient outcomes and prognosis as well as guide therapeutic intervention and rehabilitation in non-treated animals and potentially human patients that do not receive interventional treatments. Neural stem cell–derived extracellular vesicle (NSC EV) was a disruptive therapy because NSC EV administration post-stroke disrupted MLS correlations observed in non-treated stroked animals. MLS was not associated with survival and functional outcomes in NSC EV–treated animals. In contrast to untreated animals, NSC EVs improved stroked animal outcomes regardless of MLS severity.

Midline Shift vs. Mid-Surface Shift: Correlation with Outcome of Traumatic Brain Injuries

Traumatic brain injury (TBI) is a major health and socioeconomic problem globally that is associated with a high level of mortality. Early and accurate diagnosis and prognosis of TBI is important in patient management and preventing any secondary injuries. Computer tomography (CT) imaging assists physicians in diagnosing injury and guiding treatment. One of the clinical parameters extracted from CT images is midline shift, a measure of linear displacement in brain structure, which is correlated with TBI patient outcomes. However, only a tiny fraction of the overall tissue displacement is quantified through this parameter. In this paper, a novel measurement of overall mid-surface shift is proposed that quantifies the total volume of brain tissue shifted across the midline. When compared to traditional midline shift, mid-surface shift has a stronger correlation with TBI patient outcomes.

Automatic Quantification of Computed Tomography Features in Acute Traumatic Brain Injury

Traumatic brain injury is a complex and diverse medical condition with a high frequency of intracranial abnormalities. These can typically be visualized on a computed tomography (CT) scan, which provides important information for further patient management, such as the need for operative intervention. In order to quantify the extent of acute intracranial lesions and associated secondary injuries, such as midline shift and cisternal compression, visual assessment of CT images has limitations, including observer variability and lack of quantitative interpretation. Automated image analysis can quantify the extent of intracranial abnormalities and provide added value in routine clinical practice. In this article, we present icobrain, a fully automated method that reliably computes acute intracranial lesions volume based on deep learning, cistern volume, and midline shift on the noncontrast CT image of a patient. The accuracy of our method is evaluated on a subset of the multi-center data set from the CENTER-TBI (Collaborative European Neurotrauma Effectiveness Research in Traumatic Brain Injury) study for which expert annotations were used as a reference. Median volume differences between expert assessments and icobrain are 0.07 mL for acute intracranial lesions and -0.01 mL for cistern segmentation. Correlation between expert assessments and icobrain is 0.91 for volume of acute intracranial lesions and 0.94 for volume of the cisterns. For midline shift computations, median error is -0.22 mm, with a correlation of 0.93 with expert assessments.

Brain ultrasonography: methodology, basic and advanced principles and clinical applications. A narrative review

Brain ultrasonography can be used to evaluate cerebral anatomy and pathology, as well as cerebral circulation through analysis of blood flow velocities. Transcranial colour-coded duplex sonography is a generally safe, repeatable, non-invasive, bedside technique that has a strong potential in neurocritical care patients in many clinical scenarios, including traumatic brain injury, aneurysmal subarachnoid haemorrhage, hydrocephalus, and the diagnosis of cerebral circulatory arrest. Furthermore, the clinical applications of this technique may extend to different settings, including the general intensive care unit and the emergency department. Its increasing use reflects a growing interest in non-invasive cerebral and systemic assessment. The aim of this manuscript is to provide an overview of the basic and advanced principles underlying brain ultrasonography, and to review the different techniques and different clinical applications of this approach in the monitoring and treatment of critically ill patients.