Reduction of Midline Shift Following Decompressive Hemicraniectomy for Malignant Middle Cerebral Artery Infarction

Clinical implications of cerebral venous outflow pattern in malignant middle cerebral artery infarction

BACKGROUND

Malignant middle cerebral artery (MCA) infarction is one of the most devastating strokes. However, the role of the cerebral venous outflow pattern in malignant MCA infarction is not well established. We investigated the association between the transverse sinus (TS) shape and functional outcomes in patients with malignant MCA infarction.

METHODS

This retrospective cohort study included patients with malignant MCA infarction. Baseline characteristics, clinical variables, and cerebral venous outflow patterns (TS shape) were obtained. Incomplete TS shapes are referred to as unilateral TS hypoplasia, TS aplasia, or TS occlusion. We analyzed the effect of an incomplete TS shape on functional outcomes after malignant MCA infarction. The main outcome assessed was the change in ordinal shifts within the modified Rankin Scale score, indicating a deterioration in the outcome at three months.

RESULTS

Among 71 patients with malignant MCA infarction, incomplete TS shapes were observed in 33 (46.5 %). There were no significant differences in the baseline characteristics, vascular risk factors, or factors associated with malignant MCA infarction. Patients with incomplete TS shapes had a higher proportion of unfavorable functional outcomes (5.0 [4.0-5.0] vs. 5.0 [5.0-6.0], P < 0.001). Multivariable ordinal logistic regression analysis showed that patients with incomplete TS shapes (odds ratio = 6.30, 95 % confidence interval = 2.42-17.90, P < 0.001) had a substantial shift towards the unfavorable functional outcome at 3 months.

CONCLUSIONS

Among patients diagnosed with malignant MCA infarction, those with incomplete TS shapes had poorer functional outcomes and higher mortality rates. This underscores the significant clinical association between cerebrovenous patterns and functional outcomes.

Effects of cerebral venous outflow patterns on functional outcome in space-occupying cerebellar infarction

BACKGROUND

Space-occupying cerebellar infarction can be catastrophic, leading to brainstem compression, transtentorial herniation, and obstructive hydrocephalus. Herein, we investigated the association between the venous outflow pattern based on transverse sinus (TS) shape and the outcome of space-occupying cerebellar infarction.

METHODS

Patients with space-occupying cerebellar infarctions were enrolled, and data on baseline demographics, clinical factors, and venous outflow patterns, including the type of TS were collected. Low-functioning ipsilateral TS was defined as aplasia, occlusion, or hypoplasia on the side ipsilateral to the space-occupying cerebellar infarction. Conversely, properly functioning ipsilateral TS was defined as: 1) bilateral symmetric TS and 2) normal ipsilateral TS with aplasia, occlusion, or hypoplasia observed on the side contralateral to the space-occupying cerebellar infarction. The primary outcome was the attainment of a modified Rankin Scale (mRS) score of 0-2 at three months.

RESULTS

Among 42 patients, low-functioning ipsilateral TS was observed in 17 (40.5 %). Initial National Institutes of Health Stroke Scale score was significantly higher in patients with properly functioning ipsilateral TS (0.0 [0.0-1.0] vs. 2.0 [1.0-3.0], P=0.010). Moreover, the primary outcome was significantly more favorable in patients with low-functioning ipsilateral TS (1.0 [1.0-2.0] vs. 3.0 [1.0-3.0], P=0.016). Multivariable logistic regression analysis showed that patients with low-functioning ipsilateral TS (P=0.040) was associated with functional independence.

CONCLUSIONS

Patients with low-functioning ipsilateral TS exhibit more favorable outcomes than those with properly functioning ipsilateral TS in space-occupying cerebellar infarctions. The assessment of venous outflow functionality is a potential predictor of functional outcomes in space-occupying cerebellar infarctions.

Blood pressure variability and functional outcome after decompressive hemicraniectomy in malignant middle cerebral artery infarction

BACKGROUND AND PURPOSE

Malignant middle cerebral artery infarction (MMI) is a severe condition with a high mortality rate. While decompressive hemicraniectomy has been demonstrated to reduce mortality, there is limited knowledge regarding blood pressure (BP) management following the surgery. This study aimed to investigate whether early blood pressure variability after surgery is associated with functional outcomes.

METHODS

This study was a retrospective cohort analysis of patients with MMI who underwent decompressive hemicraniectomy. We calculated BP variability (BPV) by measuring BP hourly over a 72-h period following surgery. We investigated the association between BPV parameters and functional outcomes at 3-month. Additionally, we analyzed which specific time intervals within the 72 h post-surgery BPV were associated with functional outcomes.

RESULTS

A total of 110 patients were eligible for analysis. The mean age was 63.1 ± 13.1 years, and 57 (51.8%) were men. Among the systolic BPV parameters, the coefficient of variance showed a significant association with functional outcomes at 3-month (adjusted odds ratio [AOR]: 0.82, 95% CI: 0.69-0.95), and this association remained significant after adjusting for the antihypertensive agents use (AOR: 0.82, 95% CI: 0.70-0.95). In contrast, diastolic BPV parameters did not show a significant association with functional outcomes. Systolic BPV during the 0- to 24-h period of the 72-h observation was significantly associated with functional outcomes (AOR: 0.87, 95% CI: 0.76-0.98).

CONCLUSION

Our study identified a significant association between systolic BPV and 3-month functional outcomes in MMI patients who underwent decompressive hemicraniectomy. This association persisted regardless of the use of antihypertensive agents, particularly during the hyperacute phase within the first 24 h post-surgery.

Intracranial pressure trends and clinical outcomes after decompressive hemicraniectomy in malignant middle cerebral artery infarction

BACKGROUND

Malignant middle cerebral artery infarction (MMI) is associated with a high incidence of severe disability and mortality. Decompressive hemicraniectomy has become a recognized treatment that can improve the prognosis for patients if performed within a certain time window. Nevertheless, despite this intervention, a mortality rate of approximately 20-40% persists following the surgery. The trends and clinical implications of intracranial pressure (ICP) in these situations remain unclear. We aimed to investigate whether intracranial pressure (ICP) trends are associated with clinical outcomes in patients undergoing decompressive hemicraniectomy for MMI.

METHODS

This retrospective cohort study included consecutive patients with MMI who underwent decompressive craniectomy and received ICP monitoring after surgery. Using a linear mixed model, we categorized the patients into ICP increase and decrease groups based on the ICP values obtained over 192 h. We then compared the proportion of 3-month favorable outcomes (modified Rankin Scale of 0-4) and mortality rates between these groups.

RESULTS

Of 112 MMI patients who underwent decompressive hemicraniectomy, 66 (58.9%) received invasive ICP monitoring. ICP monitoring was performed for a median of 146.5 h (IQR 72.5-181.8). Among the 66 patients, 37 (56.1%) were in the ICP increase group, and 29 (43.9%) were in the ICP decrease group. During the monitoring period, the initial monitored ICP and peak ICP did not significantly differ between the ICP increase and decrease groups. However, the ICP trend was significantly different between the two groups (P < 0.001). In multivariable logistic regression analyses, the ICP increase group had a significantly lower proportion of 3-month favorable outcomes compared to the ICP decrease group (adjusted OR 0.11; 95% CI, 0.01-0.59; P = 0.019), and significantly higher mortality in the intensive care unit (adjusted OR 6.98; 95% CI, 1.37-54.6; P = 0.031).

CONCLUSIONS

In MMI patients, continuous ICP monitoring could be useful for detecting those with an increasing ICP trend that may be associated with unfavorable clinical outcomes.

Radiologic and Blood Markers Predicting Long-Term Neurologic Outcome Following Decompressive Craniectomy for Malignant Ischemic Stroke: A Preliminary Single-Center Study

BACKGROUND

 Malignant ischemic stroke (MIS) is defined by progressive cerebral edema leading to increased intracranial pressure (ICP), compression of neural structures, and, eventually, death. Decompressive craniectomy (DC) has been advocated as a lifesaving procedure in the management of patients with MIS. This study aims to identify pre- and postoperative predictive variables of neurologic outcomes in patients undergoing DC for MIS.

METHODS

 We conducted a retrospective study of patients undergoing DC in a single center from April 2016 to April 2020. Preoperative workup included baseline clinical status, laboratory data, and brain computed tomography (CT). The primary outcome was the 6-month modified Rankin score (mRS). The secondary outcome was the 30-day mortality.

RESULTS

 During data capture, a total of 58 patients fulfilled the criteria for MIS, of which 22 underwent DC for medically refractory increased ICP and were included in the present analysis. The overall median age was 58.5 years. An immediate (24 hour) postoperative extended Glasgow Outcome Scale (GOSE) score ≥5 was associated with a good 6-month mRS (1-3; p = 0.004). Similarly, low postoperative neutrophils (p = 0.002), low lymphocytes (p = 0.004), decreased neutrophil-to-lymphocyte ratio (NLR; p = 0.02), and decreased platelet-to-lymphocytes ratio (PLR; p = 0.03) were associated with good neurologic outcomes. Preoperative variables independently associated with worsened 6-month mRS were the following: increased age (odds ratio [OR]: 1.10; 95% confidence interval [CI]: 1.01-1.20; p = 0.02), increased National Institutes of Health Stroke Scale (NIHSS) score (OR: 7.8; 95% CI: 2.5-12.5; p = 0.035), Glasgow Coma Scale (GCS) score less than 8 at the time of neurosurgical referral (OR: 21.63; 95% CI: 1.42-328; p = 0.02), and increased partial thromboplastin time (PTT) before surgery (OR: 2.11; 95% CI: 1.11-4; p = 0.02). Decreased postoperative lymphocytes confirmed a protective role against worsened functional outcomes (OR: 0.01; 95% CI: 0.01-0.4; p = 0.02). Decreased postoperative lymphocyte count was associated with a protective role against increased mRS (OR: 0.01; 95% CI: 0.01-0.4; p = 0.02). The occurrence of hydrocephalus at the postoperative CT scan was associated with 30-day mortality (p = 0.005), while the persistence of postoperative compression of the ambient and crural cistern showed a trend towards higher mortality (p = 0.07).

CONCLUSIONS

 This study reports that patients undergoing DC for MIS showing decreased postoperative blood inflammatory markers achieved better 6-month neurologic outcomes than patients with increased inflammatory markers. Similarly, poor NIHSS score, poor GCS score, increased age, and larger PTT values at the time of surgery were independent predictors of poor outcomes. Moreover, the persistence of postoperative compression of basal cisterns and the occurrence of hydrocephalus are associated with 30-day mortality.

Optic nerve sheath diameter as a quantitative parameter associated with the outcome in patients with traumatic brain injury undergoing hematoma removal

PURPOSE

To determine the association between optic nerve sheath diameter (ONSD) and outcome in patients with traumatic brain injury (TBI) who undergo hematoma removal (HR).

METHODS

This study was a retrospective analysis of data from a single center between 2016 and 2021. Adult patients with TBI who underwent HR within 24 h after admission were included in this study. Preoperative and postoperative ONSD of the surgical side and the mean ONSD of both sides were measured for analysis. The primary outcome was mortality at 30 days. Receiver operating characteristic curve analysis was performed to calculate the area under the curve (AUC) and 95% confidence interval (CI) for 30 days mortality.

RESULTS

Sixty-one patients were enrolled in the study. Among them, 48 (78.7%) survived for 30 days after admission. The AUC and 95% CI of the postoperative mean ONSD on both sides and postoperative/preoperative mean of the ONSD ratio on both sides were 0.884 [0.734-0.955] and 0.875 [0.751-0.942], respectively. The postoperative mean of both ONSDs of 6.0 mm had high accuracy as a cut-off value with a sensitivity of 85%, specificity of 83%, positive likelihood ratio (LR) of 5.0, and negative LR- of 0.18.

CONCLUSION

This study demonstrated that postoperative ONSD and the postoperative/preoperative ONSD ratio were associated with postoperative outcome in patients with TBI who underwent HR.

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.

Magnetic Resonance Imaging in Neurocritically Ill Patients: Who Fails and How?

OBJECTIVES

Performing magnetic resonance imaging (MRI) in neurocritically ill patients is challenging because it often requires sedation and withholding care in the neurological intensive care unit. This study investigated the incidence of and reasons for failed or complicated MRI (MRI-FC) in such patients.

METHODS

A consecutive series of 218 neurocritically ill patients who underwent brain MRI were retrospectively evaluated. Failed or complicated MRI included failure to obtain all ordered sequences, unscheduled sedative administration, decrease in oxygen saturation to less than 90%, hypotension (≥40-mm Hg decrease and/or use of inotropic agents), and cardiac or respiratory arrest.

RESULTS

Failed or complicated MRI occurred in 66 patients (30.3%) and included failure to obtain MRI sequences (n = 13), unscheduled use of sedatives (n = 62), oxygen desaturation (n = 9), and hypotension (n = 6). Cardiac or respiratory arrest did not occur. Use of sedative agents while in intensive care (P < 0.01), high Acute Physiology and Chronic Health Evaluation II score (P = 0.031), and low Glasgow Coma Scale score on admission (P = 0.047) were associated with MRI-FC. Scan times were longer (P = 0.004) and Glasgow Coma Scale (P < 0.001) and Richmond Agitation Sedation Scale (P = 0.003) scores were lower (P = 0.004) after imaging in patients with MRI-FC. Previous use of sedative agents was independently associated with MRI-FC (adjusted odds ratio = 3.57, 95% confidence interval = 1.78 to 7.24, P < 0.001).

CONCLUSIONS

Failed or complicated MRI was common and was associated with the use of sedative agents, severity of illness, and lower level of consciousness. Studies to ensure effective and safe performance of MRI in neurocritically ill patients are needed.

Preoperative brain shift is a prognostic factor for survival in certain neurosurgical diseases other than severe head injury: a case series and literature review

Preoperative brain shift after severe brain injury is a prognostic factor for survival. The aim of this study was to determine whether preoperative brain shift in conditions other than severe head injury has significant prognostic value. We analyzed a radiological database of 800 consecutive patients, who underwent neurosurgical treatment. Brain shift was measured at two anatomical landmarks: Monro’s foramina (MF) and the corpus callosum (CC). Four hundred seventy-three patients were included. The disease exerting the highest mean brain shift was acute subdural hematoma (MF 11.6 mm, CC 12.4 mm), followed by intraparenchymal hematoma (MF 10.2 mm, CC 10.3 mm) and malignant ischemia (MF 10.4 mm, CC 10.5 mm). On univariate analysis, brain shift was a significant negative factor for survival in all diseases (p < 0.001). Analyzed individually by group, brain shift at both anatomical landmarks had a statistically significant effect on survival in malignant ischemia and at one anatomical landmark in chronic subdural and intraparenchymal hematomas. Multivariate analysis demonstrated that the only independent factor negatively impacting survival was brain shift at MF (OR = 0.89; 95% CI: 0.84–0.95) and CC (OR = 0.90; 95% CI: 0.85–0.96). Brain shift is a prognostic factor for survival in patients with expansive intracranial lesions in certain neurosurgical diseases. MF and CC are reliable anatomical landmarks and should be quoted routinely in radiological reports as well as in neurosurgical practice.

Hemicraniectomy for Dominant vs Nondominant Middle Cerebral Artery Infarction: A Systematic Review and Meta-Analysis

OBJECTIVES

Decompressive hemicraniectomy decreases mortality and severe disability from space-occupying middle cerebral artery infarction in selected patients. However, attitudes towards hemicraniectomy for dominant-hemispheric stroke have been hesitant. This systematic review and meta-analysis examines the association of stroke laterality with outcome after hemicraniectomy.

MATERIALS AND METHODS

We performed a systematic literature search up to 6th February 2020 to retrieve original articles about hemicraniectomy for space-occupying middle cerebral artery infarction that reported outcome in relation to laterality. The primary outcome was severe disability (modified Rankin Scale 4‒6 or 5‒6 or Glasgow Outcome Scale 1‒3) or death. A two-stage combined individual patient and aggregate data meta-analysis evaluated the association between dominant-lateralized stroke and (a) short-term (≤ 3 months) and (b) long-term (> 3 months) outcome. We performed sensitivity analyses excluding studies with sheer mortality outcome, second-look strokectomy, low quality, or small sample size, and comparing populations from North America/Europe vs Asia/South America.

RESULTS

The analysis included 51 studies (46 observational studies, one nonrandomized trial, and four randomized controlled trials) comprising 2361 patients. We found no association between dominant laterality and unfavorable short-term (OR 1.00, 95% CI 0.69‒1.45) or long-term (OR 1.01, 95% CI 0.76‒1.33) outcome. The results were unchanged in all sensitivity analyses. The grade of evidence was very low for short-term and low for long-term outcome.

CONCLUSIONS

This meta-analysis suggests that patients with dominant-hemispheric stroke have equal outcome after hemicraniectomy compared to patients with nondominant stroke. Despite the shortcomings of the available evidence, our results do not support withholding hemicraniectomy based on stroke laterality.

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.

High Chloride Burden and Clinical Outcomes in Critically Ill Patients With Large Hemispheric Infarction

Background: In general, disease severity has been found to be associated with abnormal chloride levels in critically ill patients, but hyperchloremia is associated with mixed results regarding patient-centered clinical outcomes. We aimed to investigate the impact of maximum serum chloride concentration on the clinical outcomes of critically ill patients with large hemispheric infarction (LHI).

Methods: We conducted a retrospective observational cohort study using prospective institutional neurocritical care registry data from 2013 to 2018. Patients with LHIs involving over two-thirds of middle cerebral artery territory, with or without infarction of other vascular territories, and a baseline National Institutes of Health Stroke Scale score of ≥13 were assessed. Those with a baseline creatinine clearance of <15 mL/min and required neurocritical care for <72 h were excluded. Primary outcome was in-hospital mortality. Secondary outcomes included 3-month mortality and acute kidney injury (AKI) occurrence. Outcomes were compared to different maximum serum chloride levels (5 mmol/L increases) during the entire hospitalization period using multivariable logistic regression analyses.

Results: Of 90 patients, 20 (22.2%) died in-hospital. Patients who died in-hospital had significantly higher maximum serum chloride levels than did those who survived up to hospital discharge (139.7 ± 8.1 vs. 119.1 ± 10.4 mmol/L; p < 0.001). After adjusting for age, sex, and Glasgow coma scale score, each 5-mmol/L increase in maximum serum chloride concentration was independently associated with an increased risk of in-hospital mortality (adjusted odds ratio (aOR), 4.34; 95% confidence interval [CI], 1.98–9.50; p < 0.001). Maximum serum chloride level was also an independent risk factor for 3-month mortality (aOR, 1.99 [per 5 mmol/L increase]; 95% CI, 1.42–2.79; p < 0.001) and AKI occurrence (aOR, 1.57 [per 5 mmol/L increase]; 95% CI, 1.18–2.08; p = 0.002).

Conclusions: High maximum serum chloride concentrations were associated with poor clinical outcomes in critically ill patients with LHI. This study highlights the importance of monitoring serum chloride levels and avoiding hyperchloremia in this patient population.

Improvement in Midline Shift Is a Positive Prognostic Predictor for Malignant Middle Cerebral Artery Infarction Patients Undergoing Decompressive Craniectomy

Objective: The aim of this retrospective study is to evaluate the risk factors of malignant middle cerebral artery infarction (MMCAI) patients and explore an applicable prognostic predictor for MMCAI patients undergoing decompressive craniectomy (DC). Methods: Clinical data from the period 2012-2017 were retrospectively evaluated. Forty-three consecutive MMCAI patients undergoing DC were enrolled in this study. The 30-day mortality was assessed, and age, location, hypertension, pupil dilation, onset to operation duration, midline shift, and Glasgow Coma Scale (GCS) score were identified by univariate analysis and binary logistic regression. Results: In this retrospective study for DC patients, the 30-day mortality was 44.2%. In the univariate analysis, advanced age (≥60 years), right hemispheric location, hypertension, pupil dilation, shorter onset to operation duration (<48 h), improved midline shift (t = 4.214, p < 0.01), and lower pre-operation GCS score were significant predictors of death within 30 days. In binary logistic regression analysis, age [odds ratio (OR) = 1.141, 95% CI 1.011-1.287], the improvement of the midline shift (OR = 0.764, 95% CI 0.59-0.988), and pupillary dilation (OR = 15.10, 95% CI 1.374-165.954) were independent influencing factors. For the receiver operating characteristic (ROC) analysis of the relationship between post-operation outcomes and midline shift improvement, the area under the curve (AUC) was 0.844, and the cutoff point of midline shift improvement was 0.83 cm. Conclusion: Improved midline shift was a significant predictor of 30-day mortality. The improved midline shift of >0.83 cm indicated survival at 30 days.

Limiting Brain Shift in Malignant Hemispheric Infarction by Decompressive Craniectomy

OBJECTIVE

Decompressive craniectomy (DC) improves functional outcomes in selected patients with malignant hemispheric infarction (MHI), but variability in the surgical technique and occasional complications may be limiting the effectiveness of this procedure. Our aim was to evaluate predefined perioperative CT measurements for association with post-DC midline brain shift in patients with MHI.

METHODS

At two medical centers we identified 87 consecutive patients with MHI and DC between January 2007 and December 2019. We used our previously tested methods to measure the craniectomy surface area, extent of transcalvarial brain herniation, thickness of tissues overlying the craniectomy, diameter of the cerebral ventricle atrium contralateral to the stroke, extension of infarction beyond the craniectomy edges, and the pre and post-DC midline brain shifts. To avoid potential confounding from medical treatments and additional surgical procedures, we excluded patients with the first CT delayed >30 hours post-DC, resection of infarcted brain, or insertion of an external ventricular drain during DC. The primary outcome in multiple linear regression analysis was the postoperative midline brain shift.

RESULTS

We analyzed 72 qualified patients. The average midline brain shift decreased from 8.7 mm pre-DC to 5.4 post-DC. The only factors significantly associated with post-DC midline brain shift at the p<0.01 level were preoperative midline shift (coefficient 0.32, standard error 0.10, p=0.002) and extent of transcalvarial brain herniation (coefficient -0.20, standard error 0.05, p <0.001).

CONCLUSIONS

In patients with MHI and DC, smaller post-DC midline shift is associated with smaller pre-DC midline brain shift and greater transcalvarial brain herniation. This knowledge may prove helpful in assessing DC candidacy and surgical success. Additional studies to enhance the surgical success of DC are warranted.

Thromboelastography for prediction of hemorrhagic transformation in patients with acute ischemic stroke

BACKGROUND

Thromboelastography (TEG) provides a rapid assessment of the hemostatic processes of a patient in emergency settings. There are limited data on TEG as a predictive tool for hemorrhagic transformation in patients with acute ischemic stroke. We investigated whether TEG values on admission could predict hemorrhagic transformation in patients with acute ischemic stroke.

METHODS

TEG was performed prospectively in 772 patients who satisfied the criteria of the critical pathway for acute stroke that have neurologic symptoms in 6 h at the emergency department between March and December 2018. After excluding 114 patients, 628 patients were evaluated, and finally, 205 patients with acute ischemic stroke were included. The primary outcome is hemorrhagic transformation, defined as the presence of blood in brain on follow-up imaging study and secondary outcome is neurological deterioration, defined as a 2-point increase on the National Institutes of Health Stroke Scale (NIHSS) within 72 h of stroke onset.

RESULTS

Of the 205 ischemic stroke patients (mean age 67 ± 13 years, 66.3% male), hemorrhagic transformation was identified in 28 (13.7%) patients, and neurological deterioration was occurred in 24 (11.7%), and both events in 9 (4.4%). The TEG value of R (reaction time) <5 min was significantly higher in patients with hemorrhagic transformation than in patients without hemorrhagic transformation (81.1% vs. 60.5%, p = 0.027), and based on multivariable analysis, this was an independent predictor of hemorrhagic transformation (odds ratio 3.215 [95% confidence interval: 1.153-8.969]).

CONCLUSIONS

In patients with acute ischemic stroke, TEG value of R < 5 min can identify patients who have an increased risk of hemorrhagic transformation during hospitalization.

Predictors of outcome in 1-month survivors of large middle cerebral artery infarcts treated by decompressive hemicraniectomy

BACKGROUND

Decompressive hemicraniectomy (DH) increases survival without severe dependency in patients with large middle cerebral artery (LMCA) infarcts. The objective was to identify predictors of 1-year outcome after DH for LMCA infarct.

METHODS

We conducted this study in consecutive patients who underwent DH for LMCA infarcts, in a tertiary stroke centre. Using multivariable logistic regression analyses, we evaluated predictors of (1) 30-day mortality and (2) poor outcome after 1 year (defined as a modified Rankin Scale score of 4-6) in 30-day survivors.

RESULTS

Of 212 patients (133 men, 63%; median age 51 years), 35 (16.5%) died within 30 days. Independent predictors of mortality were infarct volume before DH (OR 1.10 per 10 mL increase, 95% CI 1.04 to 1.16), delay between symptom onset and DH (OR 0.41, 95% CI 0.23 to 0.73 per 12 hours increase) and midline shift after DH (OR 2.59, 95% CI 1.09 to 6.14). The optimal infarct volume cut-off to predict death was 210 mL or more. Among the 177 survivors, 77 (43.5%) had a poor outcome at 1 year. Independent predictors of poor outcome were age (OR 1.08 per 1 year increase, 95% CI 1.03 to 1.12) and weekly alcohol consumption of 300 g or more (OR 5.30, 95% CI 2.20 to 12.76), but not infarct volume.

CONCLUSION

In patients with LMCA infarcts treated by DH, stroke characteristics (infarct volume before DH, midline shift after DH and early DH) predict 30-day mortality, while patients' characteristics (age and excessive alcohol intake) predict 1-year outcome survivors.

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.

A roadmap for promoting endogenous in situ tissue restoration using inductive bioscaffolds after acute brain injury

The regeneration of brain tissue remains one of the greatest unsolved challenges in medicine and by many is considered unfeasible. Indeed, the adult mammalian brain does not regenerate tissue, but there is ongoing endogenous neurogenesis, which is upregulated after injury and contributes to tissue repair. This endogenous repair response is a conditio sine que non for tissue regeneration. However, scarring around the lesion core and cavitation provide unfavorable conditions for tissue regeneration in the brain. Based on the success of using extracellular matrix (ECM)-based bioscaffolds in peripheral soft tissue regeneration, it is plausible that the provision of an inductive ECM-based hydrogel inside the volumetric tissue loss can attract neural cells and create a de novo viable tissue. Following perturbation theory of these successes in peripheral tissues, we here propose 9 perturbation parts (i.e. requirements) that can be solved independently to create an integrated series to build a functional and integrated de novo neural tissue. Necessities for tissue formation, anatomical and functional connectivity are further discussed to provide a new substrate to support the improvement of behavioral impairments after acute brain injury. We also consider potential parallel developments of this tissue engineering effort that can support therapeutic benefits in the absence of de novo tissue formation (e.g. structural support to veterate brain tissue). It is envisaged that eventually top-down inductive "natural" bioscaffolds composed of decellularized tissues (i.e. ECM) will be replaced by bottom-up synthetic designer hydrogels that will provide very defined structural and signaling properties, potentially even opening up opportunities we currently do not envisage using natural materials.

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

Midline shift (MLS) of the brain is an important feature that can be measured using various imaging modalities including X-ray, ultrasound, computed tomography, and magnetic resonance imaging. Shift of midline intracranial structures helps diagnosing intracranial lesions, especially traumatic brain injury, stroke, brain tumor, and abscess. Being a sign of increased intracranial pressure, MLS is also an indicator of reduced brain perfusion caused by an intracranial mass or mass effect. We review studies that used the MLS to predict outcomes of patients with intracranial mass. In some studies, the MLS was also correlated to clinical features. Automated MLS measurement algorithms have significant potentials for assisting human experts in evaluating brain images. In symmetry-based algorithms, the deformed midline is detected and its distance from the ideal midline taken as the MLS. In landmark-based ones, MLS was measured following identification of specific anatomical landmarks. To validate these algorithms, measurements using these algorithms were compared to MLS measurements made by human experts. In addition to measuring the MLS on a given imaging study, there were newer applications of MLS that included comparing multiple MLS measurement before and after treatment and developing additional features to indicate mass effect. Suggestions for future research are provided.

Decompressive hemicraniectomy for malignant middle cerebral artery infarction including patients with additional involvement of the anterior and/or posterior cerebral artery territory-outcome analysis and definition of prognostic factors

BACKGROUND

According to current evidence, adding decompressive craniectomy (DC) to best medical therapy reduces case fatality rate of malignant middle cerebral artery infarction by 50-75%. There is currently little information available regarding the outcome of subgroups, in particular of patients with extensive infarctions exceeding the territory of the middle cerebral artery.

METHODS

The records of 101 patients with large hemispheric infarctions undergoing DC were retrospectively reviewed. Twenty-seven patients had additional ACA and/or PCA infarcts. Sequential CTs were used for postoperative follow-up. Intracranial pressure (ICP) was monitored via a ventricular catheter in comatose patients. The main aim of treatment was to keep midline shift below 10 mm and ICP below 20 mmHg. If midline shift increased despite preceding DC, repeat surgery with removal of clearly necrotic tissue was considered. For the current analysis, Glasgow Coma Scale (GCS) at 14 days and modified Rankin Scale (mRS) at 3 months were used as outcome parameters. mRS 2 and 3 were defined as "moderate disability", mRS 4 as "severe disability", and mRS 5 and 6 as "poor outcome". These outcome parameters were correlated to age, gender, side, vascular territory, and time delay after stroke, GCS at the time of decompression, maximum ICP, maximum midline shift, and delay of maximum shift.

RESULTS

The median age of the 39 female and 62 male patients was 56 years (range, 5-79 years). Overall, 12 patients died in the acute stage (11.9%). Twenty-three (22.8%) patients recovered to moderate disability at 3 months (mRS ≤ 3), 45 (44.6%) to severe disability and 33 (32.6%) suffered a poor outcome (mRS 5 or 6). Twenty patients (19.8%) required additional necrosectomy due to secondary increasing midline shift and/or intracranial hypertension. Patients recovering to moderate disability at 3 months were in the median 10 years younger than patients with less favorable outcome (P < 0.001) and had a higher GCS prior to surgery (P < 0.001). Eleven of the 27 patients with infarctions exceeding the MCA territory needed secondary surgery, indicating a higher necrosectomy rate as for isolated MCA infarction. At 3 months, the distribution of the outcomes in terms of mRS was comparable between the patients suffering from extended infarctions and patients having isolated MCA stroke. Infarctions exceeding the territory of the middle cerebral artery were seen in 30% of the group recovering to moderate disability and thus as frequent as in the groups suffering a less favorable outcome.

CONCLUSIONS

Intensified postoperative management including possible secondary decompression with necrosectomy may further reduce case fatality rate of patients with large hemispheric infarction. Age above 60 years and severely reduced level of consciousness are the most significant factors heralding unfavorable recovery. Patients suffering infarctions exceeding the MCA territory have a comparable chance of favorable recovery as patients with isolated MCA infarction.

Long-term retention of ECM hydrogel after implantation into a sub-acute stroke cavity reduces lesion volume

Salvaging or functional replacement of damaged tissue caused by stroke in the brain remains a major therapeutic challenge. In situ gelation and retention of a hydrogel bioscaffold composed of 8mg/mL extracellular matrix (ECM) can induce a robust invasion of cells within 24h and potentially promote a structural remodeling to replace lost tissue. Herein, we demonstrate a long-term retention of ECM hydrogel within the lesion cavity. A decrease of approximately 32% of ECM volume is observed over 12weeks. Lesion volume, as measured by magnetic resonance imaging and histology, was reduced by 28%, but a battery of behavioral tests (bilateral asymmetry test; footfault; rotameter) did not reveal a therapeutic or detrimental effect of the hydrogel. Glial scarring and peri-infarct astrocytosis were equivalent between untreated and treated animals, potentially indicating that permeation into host tissue is required to exert therapeutic effects. These results reveal a marked difference of biodegradation of ECM hydrogel in the stroke-damaged brain compared to peripheral soft tissue repair. Further exploration of these structure-function relationships is required to achieve a structural remodeling of the implanted hydrogel, as seen in peripheral tissues, to replace lost tissue and promote behavioral recovery.

STATEMENT OF SIGNIFICANCE

In situ gelation of ECM is essential for its retention within a tissue cavity. The brain is a unique environment with restricted access that necessitates image-guided delivery through a thin needle to access tissue cavities caused by stroke, as well as other conditions, such as traumatic brain injury or glioma resection. Knowledge about a brain tissue response to implanted hydrogels remains limited, especially in terms of long-term effects and potential impact on behavioral function. We here address the long-term retention of hydrogel within the brain environment, its impact on behavioral function, as well as its ability to reduce further tissue deformation caused by stroke. This study highlights considerable differences in the brain's long-term response to an ECM hydrogel compared to peripheral soft tissue. It underlines the importance of understanding the effect of the structural presence of a hydrogel within a cavity upon host brain tissue and behavioral function. As demonstrated herein, ECM hydrogel can fill a cavity long-term to reduce further progression of the cavity, while potentially serving as a reservoir for local drug or cell delivery.

Multidisciplinary Approach to Decrease In-Hospital Delay for Stroke Thrombolysis

Background and Purpose

Decreasing the time delay for thrombolysis, including intravenous thrombolysis (IVT) with tissue plasminogen activator and intra-arterial thrombectomy (IAT), is critical for decreasing the morbidity and mortality of patients experiencing acute stroke. We aimed to decrease the in-hospital delay for both IVT and IAT through a multidisciplinary approach that is feasible 24 h/day.

Methods

We implemented the Stroke Alert Team (SAT) on May 2, 2016, which introduced hospital-initiated ambulance prenotification and reorganized in-hospital processes. We compared the patient characteristics, time for each step of the evaluation and thrombolysis, thrombolysis rate, and post-thrombolysis intracranial hemorrhage from January 2014 to August 2016.

Results

A total of 245 patients received thrombolysis (198 before SAT; 47 after SAT). The median door-to-CT, door-to-MRI, and door-to-laboratory times decreased to 13 min, 37.5 min, and 8 min, respectively, after SAT implementation (P<0.001). The median door-to-IVT time decreased from 46 min (interquartile range [IQR] 36–57 min) to 20.5 min (IQR 15.8–32.5 min; P<0.001). The median door-to-IAT time decreased from 156 min (IQR 124.5–212.5 min) to 86.5 min (IQR 67.5–102.3 min; P<0.001). The thrombolysis rate increased from 9.8% (198/2,012) to 15.8% (47/297; P=0.002), and the post-thrombolysis radiological intracranial hemorrhage rate decreased from 12.6% (25/198) to 2.1% (1/47; P=0.035).

Conclusions

SAT significantly decreased the in-hospital delay for thrombolysis, increased thrombolysis rate, and decreased post-thrombolysis intracranial hemorrhage. Time benefits of SAT were observed for both IVT and IAT and during office hours and after-hours.

Intracranial Pressure Soon After Hemicraniectomy in Malignant Middle Cerebral Artery Infarction

BACKGROUND

Decompressive hemicraniectomy reduces secondary brain injury related to brain edema and increased intracranial pressure (ICP) in patients with malignant middle cerebral artery infarction (MMI). However, a substantial proportion of patients still die despite hemicraniectomy due to refractory brain swelling.

OBJECTIVE

We aim to investigate whether ICP measured immediately after hemicraniectomy may indicate decompression effects and predict survival in patients with MMI.

METHODS

We included 25 patients with MMI who underwent ICP monitoring and brain computed tomography within the first hour of hemicraniectomy. Midline shifts were measured as radiological surrogates of decompression. The Glasgow Coma Scale and pupillary enlargements during the first day after hemicraniectomy were assessed as clinical surrogates of decompression. Long-term survival status at 6 months was used as the final outcome. We analyzed the relationships between early ICP and findings of midline shift, Glasgow Coma Scale, pupillary enlargement, and survival.

RESULTS

Initial ICP was correlated with mean ICP ( P < .001) and maximal ICP ( P < .001) during the first postoperative day. Intracranial pressure was associated with midline shifts ( P = .009), lower Glasgow Coma Scale scores ( P = .025), and the pupillary enlargement ( P = .015). Sixteen (64.0%) patients survived at 6 months. In a Cox proportional hazard model, elevated ICP was associated with mortality at 6 months (hazard ratio: 1.13; 95% confidence interval: 1.03-1.24; P = .008).

CONCLUSION

Increase in ICP soon after hemicraniectomy was associated with midline shift, poor neurological status, and mortality in patients with MMI. Measurements of ICP soon after hemicraniectomy may permit earlier interventions as well as more refined clinical assessments.