Association of clinical outcome and imaging endpoints in extensive ischemic stroke-comparing measures of cerebral edema.

OBJECTIVES: Ischemic edema is associated with worse clinical outcomes, especially in large infarcts. Computed tomography (CT)-based densitometry allows direct quantification of absolute edema volume (EV), which challenges indirect biomarkers like midline shift (MLS). We compared EV and MLS as imaging biomarkers of ischemic edema and predictors of malignant infarction (MI) and very poor clinical outcome (VPCO) in early follow-up CT of patients with large infarcts. MATERIALS AND METHODS: Patients with anterior circulation stroke, large vessel occlusion, and Alberta Stroke Program Early CT Score (ASPECTS) ≤ 5 were included. VPCO was defined as modified Rankin scale (mRS) ≥ 5 at discharge. MLS and EV were quantified at admission and in follow-up CT 24 h after admission. Correlation was analyzed between MLS, EV, and total infarct volume (TIV). Multivariable logistic regression and receiver operating characteristics curve analyses were performed to compare MLS and EV as predictors of MI and VPCO. RESULTS: Seventy patients (median TIV 110 mL) were analyzed. EV showed strong correlation to TIV (r = 0.91, p < 0.001) and good diagnostic accuracy to classify MI (EV AUC 0.74 [95%CI 0.61-0.88] vs. MLS AUC 0.82 [95%CI 0.71-0.94]; p = 0.48) and VPCO (EV AUC 0.72 [95%CI 0.60-0.84] vs. MLS AUC 0.69 [95%CI 0.57-0.81]; p = 0.5) with no significant difference compared to MLS, which did not correlate with TIV < 110 mL (r = 0.17, p = 0.33). CONCLUSION: EV might serve as an imaging biomarker of ischemic edema in future studies, as it is applicable to infarcts of all volumes and predicts MI and VPCO in patients with large infarcts with the same accuracy as MLS. CLINICAL RELEVANCE STATEMENT: Utilization of edema volume instead of midline shift as an edema parameter would allow differentiation of patients with large and small infarcts based on the extent of edema, with possible advantages in the prediction of treatment effects, complications, and outcome. KEY POINTS: • CT densitometry-based absolute edema volume challenges midline shift as current gold standard measure of ischemic edema. • Edema volume predicts malignant infarction and poor clinical outcome in patients with large infarcts with similar accuracy compared to MLS irrespective of the lesion extent. • Edema volume might serve as a reliable quantitative imaging biomarker of ischemic edema in acute stroke triage independent of lesion size.

Association of Dynamic Trajectories of Time-Series Data and Life-Threatening Mass Effect in Large Middle Cerebral Artery Stroke.

BACKGROUND: Life-threatening, space-occupying mass effect due to cerebral edema and/or hemorrhagic transformation is an early complication of patients with middle cerebral artery stroke. Little is known about longitudinal trajectories of laboratory and vital signs leading up to radiographic and clinical deterioration related to this mass effect. METHODS: We curated a retrospective data set of 635 patients with large middle cerebral artery stroke totaling 95,463 data points for 10 longitudinal covariates and 40 time-independent covariates. We assessed trajectories of the 10 longitudinal variables during the 72 h preceding three outcomes representative of life-threatening mass effect: midline shift ≥ 5 mm, pineal gland shift (PGS) > 4 mm, and decompressive hemicraniectomy (DHC). We used a "backward-looking" trajectory approach. Patients were aligned based on outcome occurrence time and the trajectory of each variable was assessed before that outcome by accounting for cases and noncases, adjusting for confounders. We evaluated longitudinal trajectories with Cox proportional time-dependent regression. RESULTS: Of 635 patients, 49.0% were female, and the mean age was 69 years. Thirty five percent of patients had midline shift ≥ 5 mm, 24.3% of patients had PGS > 4 mm, and 10.7% of patients underwent DHC. Backward-looking trajectories showed mild increases in white blood cell count (10-11 K/UL within 72 h), temperature (up to half a degree within 24 h), and sodium levels (1-3 mEq/L within 24 h) before the three outcomes of interest. We also observed a decrease in heart rate (75-65 beats per minute) 24 h before DHC. We found a significant association between increased white blood cell count with PGS > 4 mm (hazard ratio 1.05, p value 0.007). CONCLUSIONS: Longitudinal profiling adjusted for confounders demonstrated that white blood cell count, temperature, and sodium levels appear to increase before radiographic and clinical indicators of space-occupying mass effect. These findings will inform the development of multivariable dynamic risk models to aid prediction of life-threatening, space-occupying mass effect.

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.

Impact of initial midline shift in glioblastoma on survival.

The impact of midline shift (MLS) on long-term survival and progression in glioblastoma (GBM) is unknown. The objective of this study was to analyze the influence of mass effect on survival and progression with consideration of the patient demographics, tumor morphology, operative techniques, molecular pathology, and postoperative treatment. One hundred ninety-eight patients with GBM were analyzed retrospectively. Both MLS groups (< or ≥ 10 mm) were compared with regard to survival, progression-free survival (PFS), and postoperative course of Karnofsky Performance Status (KPS). A two-sided Fisher exact test showed no statistically significant differences in the confounders between the low- and high-MLS groups. The median survival was 18.0 months (95% confidence interval (CI) = 15.3-20.7) in the low-MLS group (n = 173) and 9.0 months (95% CI = 4.8-13.2) in the high-MLS group (n = 25) (p = 0.045). In the high-MLS group, 59.1% (13/22) with an initially high MLS had a KPS of less than 70% after 3 months, whereas 20.5% of the low-MLS group had a KPS of less than 70% (p < 0.001). Binary logistic regression analysis including the O-6-methylguanine-DNA methyltransferase (MGMT) status, extent of resection, baseline KPS, and MIB-I index showed low MLS as the only predictor for survival at 12 months (p = 0.046, odds ratio (OR) = 2.70, 95% CI = 1.0-7.2). Median PFS was 6.0 months in the high-MLS group and 9.0 months in the low-MLS group (log-rank test; p = 0.08). An initial midline shift of 10 mm or greater seems to be an imaging characteristic that independently predicts the survival in glioblastoma.

Drain type after burr-hole drainage of chronic subdural hematoma in geriatric patients: a subanalysis of the cSDH-Drain randomized controlled trial.

OBJECTIVE: Chronic subdural hematoma (cSDH) occurs more frequently in elderly patients, while older patient age is associated with worse postoperative outcome following burr-hole drainage (BHD) of cSDH. The cSDH-Drain trial showed comparable recurrence rates after BHD and placement of either a subperiosteal drain (SPD) or subdural drain (SDD). Additionally, an SPD showed a significantly lower rate of infections as well as iatrogenic parenchymal injuries through drain misplacement. This post hoc analysis aims to compare recurrence rates and clinical outcomes following BHD of cSDH and the placement of SPDs or SDDs in elderly patients. METHODS: The study included 104 patients (47.3%) 80 years of age and older from the 220 patients recruited in the preceding cSDH-Drain trial. SPDs and SDDs were compared with regard to recurrence rate, morbidity, mortality, and clinical outcome. A post hoc analysis using logistic regression, comparing the outcome measurements for patients < 80 and ≥ 80 years old in a univariate analysis and stratified for drain type, was further completed. RESULTS: Patients ≥ 80 years of age treated with an SDD showed higher recurrence rates (12.8%) compared with those treated with an SPD (8.2%), without a significant difference (p = 0.46). Significantly higher drain misplacement rates were observed for patients older than 80 years and treated with an SDD compared with an SPD (0% vs 20%, p = 0.01). Comparing patients older than 80 years to younger patients, significantly higher overall mortality (15.4% vs 5.2%, p = 0.012), 30-day mortality (3.8% vs 0%, p = 0.033), and surgical mortality (2.9% vs 1.7%, p = 0.034) rates were observed. Clinical outcome at the 12-month follow-up was significantly worse for patients ≥ 80 years old, and logistic regression showed a significant association of age with outcome, while drain type had no association with outcome. CONCLUSIONS: The initial findings of the cSDH-Drain trial and the findings of this subanalysis suggest that SPD may be warranted in elderly patients. As opposed to drain type, patient age (> 80 years) was significantly associated with worse outcome, as well as higher morbidity and mortality rates.

Drains result in greater reduction of subdural width and midline shift in burr hole evacuation of chronic subdural haematoma.

BACKGROUND: Drain insertion following chronic subdural haematoma (CSDH) evacuation reduces recurrence and improves outcomes. The mechanism of this improvement is uncertain. We assessed whether drains result in improved postoperative imaging, and which radiological factors are associated with recurrence and functional outcome. METHODS: A multi-centre, prospective cohort study of CSDH patients was performed between May 2013 and January 2014. Patients aged > 16 years undergoing burr hole evacuation of primary CSDH with pre- and postoperative imaging were included in this subgroup analysis. Baseline and clinical details were collected. Pre- and postoperative maximal subdural width and midline shift (MLS) along with clot density were recorded. Primary outcomes comprised mRS at discharge and symptomatic recurrence requiring re-drainage. Comparisons were made using multiple logistic regression. RESULTS: Three hundred nineteen patients were identified for inclusion. Two hundred seventy-two of 319 (85%) patients underwent drain insertion at the time of surgery versus 45/319 (14%) who did not. Twenty-nine of 272 patients who underwent drain insertion experienced recurrence (10.9%) versus 9 of 45 patients without drain insertion (20.5%; p = 0.07). Overall change in median subdural width was significantly greater in the drain versus 'no drain' groups (11 mm versus 6 mm, p < 0.01). Overall change in median midline shift (MLS) was also significantly greater in the drain group (4 mm versus 3 mm, p < 0.01). On multivariate analysis, change in maximal width and MLS were significant predictors of recurrence, although only the former remained a significant predictor for functional outcome. CONCLUSIONS: The use of subdural drains results in significantly improved postoperative imaging in burr hole evacuation of CSDH, thus providing radiological corroboration for their recommended use.

Risk factors associated with the progression of extra-axial hematoma in the original frontotemporoparietal site after contralateral decompressive surgery in traumatic brain injury patients.

PURPOSE: To introduced our experience with progressive extra-axial hematoma (EAH) in the original frontotemporoparietal (FTP) site after contralateral decompressive surgery (CDS) in traumatic brain injury patients and discuss the risk factors associated with this dangerous situation. METHODS: This retrospective study was conducted on 941 patients with moderate or severe TBI treated in Daping Hospital, Army Medical University, Chongqing, China in a period over 5 years (2013-2017). Only patients with bilateral lesion, the contralateral side being the dominant lesion, and decompressive surgery on the contralateral side conducted firstly were included. Patients were exclude if (1) they underwent bilateral decompression or neurosurgery at the original location firstly; (2) although surgery was performed first on the contralateral side, surgery was done again at the contralateral side due to re-bleeding or complications; (3) patients younger than 18 years or older than 80 years; and (4) patients with other significant organ injury or severe disorder or those with abnormal coagulation profiles. Clinical and radiographic variables reviewed were demographic data, trauma mechanisms, neurological condition assessed by Glasgow coma scale (GCS) score at admission, pupil size and reactivity, use of mannitol, time interval from trauma to surgery, Rotterdam CT classification, type and volume of EAH, presence of a skull fracture overlying the EAH, status of basal cistern, size of midline shift, associated brain lesions and types, etc. Patients were followed-up for at least 6 months and the outcome was graded by Glasgow outcome scale (GOS) score as favorable (scores of 4-5) and unfavorable (scores of 1-3). Student's t-test was adopted for quantitative variables while Pearson Chi-squared test or Fisher's exact test for categorical variables. Multivariate logistic regression analysis was also applied to estimate the significance of risk factors. RESULTS: Initially 186 patients (19.8%) with original impact locations at the FTP site and underwent surgery were selected. Among them, 66 met the inclusion and exclusion criteria. But only 50 patients were included because the data of the other 16 patients were incomplete. Progressive EAH developed at the original FTP site in 11 patients after the treatment of, with an incidence of 22%. Therefore the other 39 patients were classified as the control group. Multivariate logistic regression analysis showed that both the volume of the original hematoma and the absence of an apparent midline shift were significant predictors of hematoma progression after decompressive surgery. Patients with fracture at the original impact site had a higher incidence of progressive EAH after CDS, however this factor was not an important predictor in the multivariate model. We also found that patients with progressive EAH had a similar favorable outcome with control group. CONCLUSION: Progressive EAH is correlated with several variables, such as hematoma volumes ≥10 mL at the original impact location and the absence of an apparent midline shift (<5 mm). Although progressive EAH is devastating, timely diagnosis with computed tomography scans and immediate evacuation of the progressive hematoma can yield a favorable result.

Transcranial Doppler and Optic Nerve Sonography.

Transcranial Doppler is a bedside procedure that measures linear cerebral blood flow velocity (CBFV) and the pulsatility index through the intracranial circulation. Transcranial color-coded duplex Doppler (TCCD) provides both CBFV and B-mode functions. In this review they are both referred to as brain ultrasound TCCD. Brain ultrasound can be applied in various environments, including out-of-hospital, emergency room, surgery, intensive care, and ward settings. The most common neurologic disease processes evaluated with TCCD are subarachnoid hemorrhage, traumatic brain injury, and ischemic and hemorrhagic stroke. However, TCCD also is used outside the neuroenvironment for diseases such as sickle cell anemia or for cerebral hemodynamic assessment during the cardiovascular perioperative period. In these applications, TCCD can be used for the detection of cerebral vessel occlusion, estimation of cerebrovascular reactivity, right-to-left cardiac shunts, noninvasive estimation of cerebral perfusion and intracranial pressure, optic nerve sheath diameter, midline shift, hydrocephalus, and the presence of foreign objects. Finally, TCCD has a high accuracy in confirming total cerebral circulatory arrest and has been used as an ancillary test to support clinical diagnosis of brain death. Other indications for TCCD include assessment of collateral blood flow and embolization during carotid endarterectomy, assessment of patterns and extent of collateral circulation in severe stenosis or occlusion, assessment of patent foramen ovale/paradoxical embolism, assessment of arteriovenous malformations and studying their supply arteries and flow patterns, assessment of noncardiac right-to-left shunts, assessment of severe stenosis in the arteries of the circle of Willis, and assessment of vertebral artery dissection.

Correlation of Objective Pupillometry to Midline Shift in Acute Stroke Patients.

BACKGROUND: Pupillary dysfunction is recognized as a sign of acute neurological deterioration due to worsening mass effect in patients with hemispheric strokes. Recent neuroimaging studies suggest that horizontal displacement of brain structures may be more important than vertical displacement in explaining these pupillary findings. Pupillometers allow objective and standardized evaluation of the pupillary light reflex. We hypothesized that pupillary data (Neurological Pupil index [NPi] and constriction velocity [CV]) obtained with a hand-held pupilometer, correlate with horizontal intracranial midline shift in patients with ischemic and hemorrhagic strokes. METHODS: The ENDPANIC registry is a prospective database of pupillometer readings in neurological patients. There were 134 patients in the database with an acute ischemic stroke or intracerebral hemorrhage who had at least 2 neurologic imaging studies (CT or MRI) and pupillometer assessments performed within 6 hours of the imaging. Horizontal shift of the septum pellucidum (SPS) was measured in 293 images. We computed the correlation between SPS and the following pupillary variables: size, NPi, CV (left, right, and left-right difference), followed by a regression model to control for confounders. RESULTS: There were 94 patients (70.1%) with an ischemic stroke and 40 patients (29.9%) had an intracerebral hemorrhage. After controlling for age, race, and gender, there was a significant correlation between the SPS and NPi (left [P < .001], right [P < .001]), CV (left [P < .005], right [P < .001]) pupillary asymmetry (absolute difference between right and left; P < .05), but not between SPS and pupillary size (left or right). There was a significant correlation between the NPi and CV for the right pupil when there was a right-to-left SPS (P < .001 and P < .05, respectively), but none between the NPi and CV for the left pupil and left-to-right SPS. CONCLUSIONS: In patients with ischemic and hemorrhagic strokes, there is a significant correlation between SPS and the NPi, CV and pupillary asymmetry, but not with pupillary size.

Decompressive craniectomy for intracerebral haematoma: the influence of additional haematoma evacuation.

Intracerebral haemorrhage (ICH) may lead to intractable elevation of intracranial pressure (ICP), which may lead to decompressive craniectomy (DC). In this setting, surgical evacuation of ICH is controversially discussed. We therefore analysed radiological and clinical parameters to investigate the influence of additional haematoma evacuation to DC in patients with ICH. Forty-four patients suffering from spontaneous, hypertensive ICH between August 2007 and February 2016 underwent DC with and without ICH evacuation at the author's institution. Patients were stratified into two groups (DC without ICH evacuation versus DC with ICH evacuation). Patient characteristics, clinical and radiological findings were assessed and retrospectively analysed. Fifteen (34%) patients underwent DC with additional ICH evacuation and 29 (66%) underwent DC without ICH evacuation. Mean ICH volume was 60 ± 38 ml with no significant difference between both groups (p = 0.8). Midline shift (MLS) reduction after DC did not significantly differ between both groups (p = 0.4). Overall, 13 patients (30%) achieved a favourable outcome. DC can be performed in cases of spontaneous supratentorial ICH and pathological elevated ICP despite best medical treatment. However, additional ICH evacuation does not seem to be beneficial according to the present study and may therefore be omitted.

Prognostic significance of hematoma thickness to midline shift ratio in patients with acute intracranial subdural hematoma: a retrospective study.

Acute intracranial subdural hematoma (ASDH) is commonly associated with a grave prognosis citing a high incidence of morbidity and mortality. The parameters to decide on surgical evacuation of the hematoma are sometimes controversial. In this study, we theorized that the ratio between maximal hematoma thickness and midline shift would be varied by associated intrinsic brain pathology emanating from the trauma and would thus objectively evaluates the prognosis in ASDH. The records of patients diagnosed with ASDH who were submitted to surgical evacuation through a craniotomy were revised. Data collected included basic demographic data, preoperative general and neurological examinations, and radiological findings. The maximal thickness of the hematoma (H) on the preoperative CT brain was divided by the midline shift at the same level (MS) formulating the H/MS ratio. Postoperative data obtained included Glasgow Coma Scale (GCS), Glasgow Outcome Scale (GOS), and follow-up period. Sixty-seven eligible patients were included in the study, of which 53 (79.1%) patients were males. Mean age was 34 years. The H/MS ratio ranged from 0.69 to 1.8 with a mean of 0.93. Age above 50 years (P = 0.0218), admission GCS of less than 6 (0.0482), and H/MS ratio of 0.79 or less (P = 0.00435) were negative prognostic factors and correlated with a low postoperative GCS and GOS. H/MS ratio is a useful prognostic tool in patients diagnosed with ASDH and can be added to the armamentarium of data to improve the management decision in this cohort of patients.

Case report on the spontaneous resolution of a traumatic intracranial acute subdural haematoma: evaluation of the guidelines.

Rapid spontaneous resolution of traumatic acute subdural haematomas (ASDH) can occur but is rare. We present an 88-year-old female who presents with a large left acute subdural haematoma (ASDH) measuring 18 mm in thickness with midline shift of 10.7 mm. We managed her conservatively based upon good consciousness level and absent neurological deficits. Repeat computed tomography (CT) the following day demonstrated near complete resolution of the ASDH and midline shift regression; a further CT confirmed resolution. Most patients with large ASDH require surgical evacuation; however, in rare cases, they can resolve spontaneously with extreme rapidity. Conservative management can be a valid option in carefully selected cases.

Defining the Optimal Midline Shift Threshold to Predict Poor Outcome in Patients with Supratentorial Spontaneous Intracerebral Hemorrhage.

BACKGROUND: Midline shift (MLS) has been associated with unfavorable outcome in patients with intracerebral hemorrhage (ICH). However, the optimal criteria to define the MLS measurements that indicate future outcome in ICH patients are absent, and the quantitative threshold of MLS that differentiates favorable and poor clinical outcome should be further explored. METHODS: We enrolled patients with ICH who underwent admission computed tomography (CT) within 6 h after onset of symptoms. We assessed MLS at several locations, including the pineal gland, septum pellucidum, and cerebral falx. MLS(max) was defined as the maximum midline shift among these locations. Functional outcomes were assessed with the Modified Rankin Scale (mRS) at 3 months. We performed multivariate logistic regression analysis to investigate the MLS locations for predicting poor outcome. ROC curve analysis was used to establish whether MLS values were predictive of 90-day poor outcome. RESULTS: In 199 patients with ICH, 78 (39.2%) patients had poor functional outcome at 3-month follow-up. Pineal gland shift, septum pellucidum shift, cerebral falx shift, and MLS(max) all showed a significant difference between poor outcome and favorable outcome (p < 0.001). After adjustment for age, baseline Glasgow Coma Scale score, ICH location, time to initial CT, baseline ICH volume, and intraventricular hemorrhage, the MLS(max) was independently associated with poor outcome (p = 0.032). MLS(max) > 4 mm (our proposed optimal threshold) was more likely to have poorer outcomes than those without (p < 0.001). CONCLUSIONS: MLS(max) can be a good independent predictor of clinical outcome, and MLS(max) > 4 mm is an optimal threshold associated with poor outcome in patients with ICH.

Midline Shift is Unrelated to Subjective Pupillary Reactivity Assessment on Admission in Moderate and Severe Traumatic Brain Injury.

BACKGROUND: This study aims to determine the relationship between pupillary reactivity, midline shift and basal cistern effacement on brain computed tomography (CT) in moderate-to-severe traumatic brain injury (TBI). All are important diagnostic and prognostic measures, but their relationship is unclear. METHODS: A total of 204 patients with moderate-to-severe TBI, documented pupillary reactivity, and archived neuroimaging were included. Extent of midline shift and basal cistern effacement were extracted from admission brain CT. Mean midline shift was calculated for each ordinal category of pupillary reactivity and basal cistern effacement. Sequential Chi-square analysis was used to calculate a threshold midline shift for pupillary abnormalities and basal cistern effacement. Univariable and multiple logistic regression analyses were performed. RESULTS: Pupils were bilaterally reactive in 163 patients, unilaterally reactive in 24, and bilaterally unreactive in 17, with mean midline shift (mm) of 1.96, 3.75, and 2.56, respectively (p = 0.14). Basal cisterns were normal in 118 patients, compressed in 45, and absent in 41, with mean midline shift (mm) of 0.64, 2.97, and 5.93, respectively (p < 0.001). Sequential Chi-square analysis identified a threshold for abnormal pupils at a midline shift of 7-7.25 mm (p = 0.032), compressed basal cisterns at 2 mm (p < 0.001), and completely effaced basal cisterns at 7.5 mm (p < 0.001). Logistic regression revealed no association between midline shift and pupillary reactivity. With effaced basal cisterns, the odds ratio for normal pupils was 0.22 (95% CI 0.08-0.56; p = 0.0016) and for at least one unreactive pupil was 0.061 (95% CI 0.012-0.24; p < 0.001). Basal cistern effacement strongly predicted midline shift (OR 1.27; 95% CI 1.17-1.40; p < 0.001). CONCLUSIONS: Basal cistern effacement alone is associated with pupillary reactivity and is closely associated with midline shift. It may represent a uniquely useful neuroimaging marker to guide intervention in traumatic brain injury.

The consequence of spatial visual processing dysfunction caused by traumatic brain injury (TBI).

OBJECTIVE: A bi-modal visual processing model is supported by research to affect dysfunction following a traumatic brain injury (TBI). TBI causes dysfunction of visual processing affecting binocularity, spatial orientation, posture and balance. Research demonstrates that prescription of prisms influence the plasticity between spatial visual processing and motor-sensory systems improving visual processing and reducing symptoms following a TBI. RATIONALE: The rationale demonstrates that visual processing underlies the functional aspects of binocularity, balance and posture. The bi-modal visual process maintains plasticity for efficiency. Compromise causes Post Trauma Vision Syndrome (PTVS) and Visual Midline Shift Syndrome (VMSS). Rehabilitation through use of lenses, prisms and sectoral occlusion has inter-professional implications in rehabilitation affecting the plasticity of the bi-modal visual process, thereby improving binocularity, spatial orientation, posture and balance Main outcomes: This review provides an opportunity to create a new perspective of the consequences of TBI on visual processing and the symptoms that are often caused by trauma. It also serves to provide a perspective of visual processing dysfunction that has potential for developing new approaches of rehabilitation. CONCLUSIONS: Understanding vision as a bi-modal process facilitates a new perspective of visual processing and the potentials for rehabilitation following a concussion, brain injury or other neurological events.

Collagenase-Induced Rat Intra-Striatal Hemorrhage Mimicking Severe Human Intra-Striatal Hemorrhage.

Basal ganglia hemorrhage accounts for approximately 50% of all hemorrhagic strokes. A good rat model that produces severe intrastriatal hemorrhage (ISH) mimicking human severe ISH is lacking. The present study compared the intra-striatal injection of 0.2 U with that of 0.6 U of collagenase in inducing severe ISH in rats. Three-Tesla (3T) magnetic resonance imaging (MRI) was used to evaluate brain injuries in terms of hematoma size (volume), midline shift (MLS), and brain edema. This evaluation was further substantiated by determination of behavior and neurologic functions and mortality over 56 h. The 0.2 U collagenase caused hematoma volume increases for 10.3 to 30.1 mm³, while the 0.6 U caused 36.4 to 114.8 mm³, at post-ISH 1 h to 56 h. The 0.6 U collagenase significantly increased MLS to 1.5-3.0 times greater than the 0.2 U did at all post-intracerebral hemorrhage (ICH) time points. The MLS increased dependently with hematoma expansion with high correlation coefficients, yet no mortality occurred. These two dosages, nevertheless, caused the same pattern and severity in relative apparent diffusion coefficient (rADC) changes for three regions of interest (ROIs). Both ISH models induced consistent behavior deficits. The larger dosage produced severe brain injuries as well as neurological deficits, more closely mimicking severe human ISH. Hematoma volume and MLS can be the most useful parameters for evaluating the ISH severity in the present experimental model. The larger dosage, therefore, would be useful for investigating the pathophysiology of the severer ISH in the striatum. This may be applied for evaluating potential therapeutic strategies and outcomes in the future.

RETROSPECTIVE STUDY EVALUATING ASSOCIATIONS BETWEEN MIDLINE BRAIN SHIFT ON MAGNETIC RESONANCE IMAGING AND SURVIVAL IN DOGS DIAGNOSED WITH MENINGOENCEPHALITIS OF UNKNOWN ETIOLOGY.

Difficulty has been encountered when trying to identify ante mortem prognostic indicators for dogs with meningoencephalitis of unknown etiology (MUE). Identifying MRI imaging parameters associated with prognosis may impact treatment decision-making for clinician and owner. Our hypotheses for this retrospective cohort study are that dogs diagnosed with MUE that had midline shift on brain MRI would have a poorer survival compared to dogs without midline shift; and that younger age, lower weight, and low cerebrospinal fluid (CSF) cell count would be correlated with improved survival. Medical records were reviewed from two institutions. Inclusion criteria included: clinical signs referable to intracranial disease, brain MRI at presentation, abnormal CSF analysis, and negative infectious disease testing. Magnetic resonance imaging scans were evaluated for midline shift using the T2-weighted transverse image at the interthalamic adhesion and at the site of maximal deviation. Fifty-two dogs met the inclusion criteria. Median midline deviation was 0.12 cm. Median survival for dogs with no shift was 906 days and with shift was 84 days. Survival was not significantly different between groups (P = 0.11). This remained true when correcting for age (P = 0.22) and CSF TNCC (total nucleated cell count) (P = 0.12). Age at the time of diagnosis (P = 0.02) and CSF TNCC (P = 0.03) were significantly associated with survival. Cerebrospinal fluid protein value (P = 0.84) and weight (P = 0.82) were not significantly associated with survival. In this study of 52 dogs with MUE, MRI evidence of midline brain shift between 0.04 and 0.3 cm at the level of the interthalamic adhesion was not associated with shorter survival.

Postural stability in patients with chronic subdural hematoma.

BACKGROUND: Gait disturbances and falls are common in patients with chronic subdural hematoma (cSDH). Postural stability is mainly visually assessed and has not been described using an objective and quantitative measurement tool. The objective of this prospective study was to evaluate postural stability in cSDH patients by measuring trunk sway during stance and gait compared to healthy elderly (HE). It was also to evaluate the relationships among postural stability and age, hematoma size, brain midline shift and hematoma location. METHODS: Using a gyroscopic method, trunk sway was measured in 22 cSDH patients preoperatively, 5 postoperatively and 58 HE during seven standing and walking tasks. Trunk sway amplitude and velocity in the anterior-posterior and medial-lateral directions were assessed. RESULTS: Postural stability was reduced in the cSDH group compared to HE for all standing tasks. During gait, the sway angle was increased while velocity was decreased in the cSDH group. Only 18 % of the patients could perform all tasks without losing their balance. Postoperatively, postural stability was normalized in the medial-lateral direction during standing. There were no correlations among age, hematoma size, brain midline shift or location of the hematoma and trunk sway. CONCLUSIONS: The majority of cSDH patients had reduced postural stability that was partly reversed soon after surgery. It was not correlated to hematoma characteristics, indicating that an increased risk to fall is present regardless of hematoma size and midline shift. This must be accounted for when handling these patients and measures taken to prevent further fall accidents during hospital stays.

Decompressive Craniectomy in Patients with Traumatic Brain Injury: Are the Usual Indications Congruent with Those Evaluated in Clinical Trials?

BACKGROUND: In patients with traumatic brain injury (TBI), multicenter randomized controlled trials have assessed decompressive craniectomy (DC) exclusively as treatment for refractory elevation of intracranial pressure (ICP). DC reliably lowers ICP but does not necessarily improve outcomes. However, some patients undergo DC as treatment for impending or established transtentorial herniation, irrespective of ICP. METHODS: We performed a population-based cohort study assessing consecutive patients with moderate-severe TBI. Indications for DC were compared with enrollment criteria for the DECRA and RESCUE-ICP trials. RESULTS: Of 644 consecutive patients, 51 (8 %) were treated with DC. All patients undergoing DC had compressed basal cisterns, 82 % had at least temporary preoperative loss of ≥1 pupillary light reflex (PLR), and 80 % had >5 mm of midline shift. Most DC procedures (67 %) were "primary," having been performed concomitantly with evacuation of a space-occupying lesion. ICP measurements influenced the decision to perform DC in 18 % of patients. Only 10 and 16 % of patients, respectively, would have been eligible for the DECRA and RESCUE-ICP trials. DC improved basal cistern compression in 76 %, and midline shift in 94 % of patients. Among patients with ≥1 absent PLR at admission, DC was associated with lower mortality (46 vs. 68 %, p = 0.03), especially when the admission Marshall CT score was 3-4 (p = 0.0005). No patients treated with DC progressed to brain death. Variables predictive of poor outcome following DC included loss of PLR(s), poor motor score, midline shift ≥11 mm, and development of perioperative cerebral infarcts. CONCLUSIONS: DC is most often performed for clinical and radiographic evidence of herniation, rather than for refractory ICP elevation. Results of previously completed randomized trials do not directly apply to a large proportion of patients undergoing DC in practice.

Ipsilateral Sinus Hypoplasia and Poor Leptomeningeal Collaterals as Midline Shift Predictors.

BACKGROUND: We explore the role of dural sinus morphology, leptomeningeal collaterals, and clot localization in the development of malignant brain edema in acute ischemic stroke in anterior circulation. METHODS: This is a single-center retrospective study of consecutive stroke patients with acute occlusion (middle cerebral artery M1 ± intracranial internal carotid artery) treated with intravenous thrombolysis (from November 2009 to November 2014). Admission computed tomography angiography data were evaluated for hypoplasia of dural sinuses, leptomeningeal collaterals, and clot location. Primary outcome was midline shift (<5 mm versus ≥5 mm) on follow-up computed tomography. Secondary outcomes were infarct volume and modified Rankin Scale score of 2 or lower at 90 days. Multivariate logistic regression was used. RESULTS: Of 86 patients (49 females), 36 (42%) had poor collaterals, 26 (30%) had ipsilesional sinus hypoplasia, and 38 (44%) had proximal clots. A midline shift of 5 mm or higher was diagnosed in 14 patients (16%). Infarct volume was larger in the group with midline shift (median: 318 mL [interquartile range {IQR} = 260-350]) than in the group without midline shift (median: 44 mL [IQR = 28-60]) (P = .007). In multivariate analysis, poor leptomeningeal collaterals (odds ratio [OR] = .11, 95% confidence interval [CI] = .03-.44, P = .002 for good collaterals) and ipsilesional sinus hypoplasia (OR = 6.43, 95% CI = 1.5-46.1, P = .008) were independently associated with a midline shift of 5 mm or higher. CONCLUSION: Patients with poor leptomeningeal collaterals and ipsilesional hypoplasia of dural sinuses are more likely to develop midline shift.