Early infarction detected by diffusion-weighted imaging in patients with subarachnoid hemorrhage

A nomogram for predicting prognostic risk factors in individuals with poor grade aneurysmal subarachnoid hemorrhage: a retrospective study

Poor-grade aneurysmal subarachnoid hemorrhage (PGASAH) is associated with high mortality and morbidity despite advanced treatments. Accurate prediction of prognosis remains a clinical challenge. This study aimed to identify independent risk factors and develop a predictive nomogram for unfavorable outcomes in PGASAH patients. This retrospective study included 348 PGASAH patients treated between 2003 and 2016. Univariate and multivariate logistic regression analyses were performed to evaluate the association of premorbid conditions, admission aSAH clinical parameters, admission laboratory parameters, and clinical complications with unfavorable outcomes, defined as mRS > 2 at 6 months. Independent predictors were identified, and a nomogram was constructed to assess predictive accuracy and clinical utility. The median age of PGASAH patients was 55.1 years, 64.9% were females. Independent predictors of unfavorable outcomes (mRS > 2) at 6 months included age > 55 years (aOR = 2.44), cardiac valve disease (aOR = 6.50), dilated pupils at admission (aOR = 2.64), early infarction (aOR = 5.56), and delayed cerebral ischemia (aOR = 5.09). The nomogram demonstrated good predictive performance with an AUC of 0.807. Decision curve analysis affirmed its clinical applicability. The intuitive nomogram helps physicians predict PGASAH prognosis at discharge, improving long-term management, optimizing resource allocation, and enhancing patient and family awareness and psychological preparedness. External validation is required for broader clinical use.

High Plasma D-Dimer Levels Correlate with Ictal Infarction and Poor Outcomes in Spontaneous Subarachnoid Hemorrhage

BACKGROUND

Early brain injury is the leading cause of poor outcomes in spontaneous subarachnoid hemorrhage (sSAH). Plasma D-dimer levels and acute cerebral ischemia have been highlighted as relevant findings in early brain injury; however, their correlation has not been substantially investigated.

METHODS

This retrospective, single-center cohort study was conducted at a tertiary emergency medical center from January 2004 to June 2022. Consecutive patients with sSAH who presented within 12 hours of ictus and underwent magnetic resonance imaging within 3 days were included. We assessed the correlation of plasma D-dimer levels with acute ischemic lesions detected on the diffusion-weighted imageing and the clinical characteristics.

RESULTS

Among 402 eligible patients (mean age, 63.5 years; 62.7% women; median time from onset to arrival, 45.5 minutes), 140 (34.8%) had acute ischemic lesions. Higher plasma D-dimer levels linearly correlated with worse neurological grades, more severe SAH on initial computed tomography, acute ischemic lesions, and poor outcomes, except for patients with neurogenic stunned myocardium. In the multivariate analysis, acute ischemic lesions were significantly associated with worse neurological grades, higher plasma D-dimer levels, bilateral loss of light reaction, and advanced age. The receiver operating characteristic curve analysis showed D-dimer levels as excellent predictors for acute ischemic lesions (area under the curve, 0.897; cut-off value, 5.7 μg/mL; P<0.0001) and unfavorable outcomes (area under the curve, 0.786; cut-off value, 4.0 μg/mL; P<0.0001).

CONCLUSIONS

High plasma D-dimer levels correlated with the appearance of acute ischemic lesions on diffusion-weighted imaging and were dose-dependently associated with worse neurological grades, more severe hemorrhage, and worse outcomes.

Systematic Review and Meta-Analysis of the Association Between Appearance of Lesions on Diffusion-Weighted Imaging and Poor Outcomes Among Patients with Intracerebral Hemorrhage

OBJECTIVE

Some patients with intracerebral hemorrhage show lesions on diffusion-weighted magnetic resonance imaging, and such lesions have been associated with a greater risk of worse prognosis. Here we meta-analyzed the available evidence for such an association.

METHODS

Studies that reported the presence or absence of lesions on diffusion-weighted imaging (DWI) after intracerebral hemorrhage as well as clinical or radiological outcomes were systematically reviewed and meta-analyzed. Clinical outcome was defined as a score of modified Rankin scale (mRS) at admission to 90 days.

RESULTS

Ten studies involving 3575 patients were included in the meta-analysis, and the incidence of DWI lesions ranged from 11.1% to 49.6%. Lesions were associated with a significantly higher risk of poor outcome (mRS scores 3-6) across 6 studies (odds ratio: 2.91; 95% confidence interval: 1.62-5.23; P < 0.001). In subgroup analysis, mRS scores 4-6 were associated with the presence of lesions on DWI (odds ratio: 2.18; 95% confidence interval: 1.31-3.60; P = 0.003). We observed similar results using 3 different definitions of lesions on DWI. Some studies have reported that recurrence of intracerebral hemorrhage was also related with DWI lesions. But there was controversy on the relationship between mortality, ischemic stroke, and hematoma volume and DWI lesions.

CONCLUSIONS

Lesions on DWI after intracerebral hemorrhage were associated with a higher risk of poor outcome, but large longitudinal studies are needed to verify this association.

Factors Associated with Early and Late Seizure Related to Aneurysmal Subarachnoid Hemorrhage

Post-stroke epilepsy may occur after aneurysmal subarachnoid hemorrhage (aSAH). Both early and late seizures could cause severe neurocognitive deficits if administration of appropriate antiseizure medication is delayed. Therefore, it is important to elucidate the risk factors for early and late seizures, which could be shared with medical teams to promptly manage seizures. There are aspects of both hemorrhage and ischemia in aSAH, and thus, numerous risk factors are considered for early and late seizures. We examined factors associated with aSAH-related early and late seizures. Among 297 patients who had aSAH and underwent direct or endovascular surgery, 25 had early seizures and 20 had late seizures. Patients who did not experience any seizures in at least 2-years of follow-up (n = 81) were used as the control group. Early seizures were associated with older age and acute severe nonneurological infection, whereas late seizures were associated with intraparenchymal lesion volume >10 mL and shunt placement. In patients with late seizures, consistency was frequently observed between electroencephalogram and the presence of intraparenchymal lesions. The frontopolar electrode on electroencephalogram was highly sensitive to abnormality in early seizures. Early seizures were induced by the patient's systemic factors, which may lower the threshold for cortical excitability. Patients with intraparenchymal lesions who undergo shunt placement should be carefully followed up for late seizures.

Clinical Significance of the CSF Pulsation Flow Sign in the Foramen of Monro on FLAIR in Patients with Aneurysmal SAH -Preliminary Report

It is known that the cerebrospinal fluid (CSF) pulsation flow sign in the lateral ventricles directly above the foramen of Monro (CPF-M) on axial fluid attenuated inversion recovery (FLAIR) is a normal physiological finding as an artifact of FLAIR. In this study, whether CPF-M can be used as a neuroradiological finding related to pathological conditions in patients with acute aneurysmal subarachnoid hemorrhage (aSAH) was investigated. CPF-M-related clinical features were retrospectively evaluated in 147 aSAH patients who underwent adequate serial MRI examinations without massive intraventricular hemorrhage (IVH) of the lateral ventricle within 48 h of ictus. The frequency of the CPF-M in the control group was 32% (57/178), 33% (40/123), and 38% (45/117) for the normal control, chronic cerebral infarction, and deep white matter lesion (WML) groups, respectively. In aSAH patients, the overall prevalence of the CPF-M was 57% (84/147), significantly higher than in the three control groups. Multivariate analysis showed that age <70 years, lower IVH Hijdra score of the fourth ventricle, absence of T₁-FLAIR mismatch, deep WMLs, old infarction, diffuse brain swelling, symptomatic delayed cerebral ischemia (DCI), shunt-dependent chronic hydrocephalus (SDCH), and favorable outcome were significantly associated with the CPF-M. Although limited to SAH patients without massive IVH of the lateral ventricles, one can conclude that, in acute aSAH, the presence of CPF-M on admission MRI suggests that the circulatory dynamics of the CSF from the basal cistern to the ventricles are approximately normal. Thus, this finding may appear to offer an indicator of a good outcome without DCI and SDCH.

The Acute Phase of Experimental Subarachnoid Hemorrhage: Intracranial Pressure Dynamics and Their Effect on Cerebral Blood Flow and Autoregulation

Clinical presentation and neurological outcome in subarachnoid hemorrhage (SAH) is highly variable. Aneurysmal SAH (aSAH) is hallmarked by sudden increase of intracranial pressure (ICP) and acute hypoperfusion contributing to early brain injury (EBI) and worse outcome, while milder or non-aneurysmal SAH with comparable amount of blood are associated with better neurological outcome, possibly due to less dramatic changes in ICP. Acute pressure dynamics may therefore be an important pathophysiological aspect determining neurological complications and outcome. We investigated the influence of ICP variability on acute changes after SAH by modulating injection velocity and composition in an experimental model of SAH. Five hundred microliters of arterial blood (AB) or normal saline (NS) were injected intracisternally over 1 (AB₁, NS₁), 10 (AB_10, NS₁₀), or 30 min (AB₃₀) with monitoring for 6 h (n = 68). Rapid blood injection resulted in highest ICP peaks (AB₁ median 142.7 mmHg [1.Q 116.7-3.Q 230.6], AB₃₀ 33.42 mmHg [18.8-38.3], p < 0.001) and most severe hypoperfusion (AB₁ 16.6% [11.3-30.6], AB₃₀ 44.2% [34.8-59.8]; p < 0.05). However, after 30 min, all blood groups showed comparable ICP elevation and prolonged hypoperfusion. Cerebral autoregulation was disrupted initially due to the immediate ICP increase in all groups except NS₁₀; only AB₁, however, resulted in sustained impairment of autoregulation, as well as early neuronal cell loss. Rapidity and composition of hemorrhage resulted in characteristic hyperacute hemodynamic changes, with comparable hypoperfusion despite different ICP ranges. Only rapid ICP increase was associated with pronounced and early, but sustained disruption of cerebral autoregulation, possibly contributing to EBI.

Effect of Early Brain Infarction After Subarachnoid Hemorrhage: A Systematic Review and Meta-Analysis

OBJECTIVE

Aneurysmal subarachnoid hemorrhage (aSAH) is an acute cerebrovascular event that leads to devastating consequences. Early brain infarction (EBI) develops very early, within the first 72 hours after bleeding, and may have a significant impact on long-term outcomes. The incidence and impact of EBI in the prognosis of aSAH remain uncertain. We performed a systematic review and meta-analysis to evaluate the incidence of EBI in patients with aSAH and determine its effect on mortality and functional outcomes.

METHODS

We performed a systematic review and meta-analysis. Inclusion criteria were 1) studies that evaluated aSAH within 72 hours after bleeding; 2) performed a brain imaging study up to 72 hours of hemorrhage; 3) used computed tomography or magnetic resonance imaging; and 4) included a description of the findings of the brain imaging study (whether or not an infarct was present).

RESULTS

Ten studies that met the criteria were included. The incidence of EBI was 17%. The risk ratio for 3-month mortality was 2.18 (95% confidence interval 1.48-3.30). The overall risk ratio for poor outcome was 2.26 (95% confidence interval 1.75-2.93).

CONCLUSIONS

EBI plays an important role in the outcome of patients with aSAH. Its significant impact could represent a new therapeutic frontier for improving outcomes of these patients.

Retrospective review of previous minor leak before major subarachnoid hemorrhage diagnosed by MRI as a predictor of occurrence of symptomatic delayed cerebral ischemia

OBJECTIVE

This study attempted to determine whether a previous minor leak correlated with the occurrence of symptomatic delayed cerebral ischemia (sDCI).

METHODS

The authors retrospectively evaluated sDCI-related clinical features and findings from MRI, including T1-weighted imaging (T1WI)–FLAIR mismatch at the time of admission, in 151 patients admitted with subarachnoid hemorrhage (SAH) within 48 hours of ictus.

RESULTS

The overall incidence of sDCI was 23% (35 of 151 patients). In all subjects, multivariate analysis revealed that World Federation of Neurosurgical Societies Grades II–V, age 70 years or older, presence of rebleeding after admission, a previous minor leak before the major SAH attack as diagnosed by T1WI-FLAIR mismatch, acute infarction on diffusion-weighted imaging, and CT SAH score were significantly associated with occurrence of sDCI. In patients with no previous minor leak before major SAH as diagnosed by T1WI-FLAIR mismatch, the incidence of sDCI was only 7% (7 of 97 patients).

CONCLUSIONS

A previous minor leak before major SAH as diagnosed by T1WI-FLAIR mismatch represents an important sDCI-related factor. When the analysis was restricted to patients with true acute SAH without a previous minor leak diagnosed by T1WI-FLAIR mismatch, the incidence of sDCI was extremely low.

MRI Detection of Cerebral Infarction in Subarachnoid Hemorrhage

OBJECTIVE

To investigate magnetic resonance imaging (MRI) detection of cerebral infarction (CI) in patients presenting with subarachnoid hemorrhage (SAH).

BACKGROUND

CI is a well-known complication of SAH that is typically detected on computed tomography (CT). MRI has improved sensitivity for acute CI over CT, particularly with multiple, small, or asymptomatic lesions.

METHODS

With IRB approval, 400 consecutive SAH patients admitted to our institution from August 2006 to March 2011 were retrospectively reviewed. Traumatic SAH and secondary SAH were excluded. Data were collected on demographics, cause of SAH, Hunt Hess and World Federation of Neurosurgical Societies grades, and neuroimaging results. MRIs were categorized by CI pattern as single cortical (SC), single deep (SD), multiple cortical (MC), multiple deep (MD), and multiple cortical and deep (MCD).

RESULTS

Among 123 (30.8 %) SAH patients who underwent MRIs during their hospitalization, 64 (52 %) demonstrated acute CI. The mean time from hospital admission to MRI was 5.7 days (range 0-29 days). Among the 64 patients with MRI infarcts, MRI CI pattern was as follows: MC in 20 (31 %), MCD in 18 (28 %), SC in 16 (25 %), SD in 3 (5 %), MD in 2 (3 %), and 5 (8 %) did not have images available for review. Most infarcts detected on MRI (39/64 or 61 %) were not visible on CT.

CONCLUSIONS

The use of MRI increases the detection of CI in SAH. Unlike CT studies, MRI-detected CI in SAH tends to involve multiple vascular territories. Studies that rely on CT may underestimate the burden of CI after SAH.

Efficacy and Safety of Treatment of Ruptured Intracranial Aneurysms

OBJECTIVE

To compare the treatment results of ruptured aneurysms treated endovascularly with aneurysms treated with microsurgical clipping.

METHODS

This prospective multicenter study recorded and analyzed 661 cases of ruptured intracranial aneurysms with consecutive subarachnoid hemorrhage treated between 1997 and 2014 at 2 large medical centers. Endovascular treatment was performed in 271 cases, and microsurgical treatment was performed in 390 cases. The treatment modality was chosen by neuroradiologists and vascular neurosurgeons and was classified by predetermined decision criteria.

RESULTS

Symptomatic ischemic stroke occurred in 46 patients (17.0%) in the endovascular group versus 26 patients (6.7%) in the microsurgery group (odds ratio [OR] = 2.86; 95% confidence interval [CI], 1.72-4.76; P < 0.0001). There was a significantly better occlusion rate (OR = 11.48; 95% CI, 5.10-25.83; P < 0.0001) in the microsurgery group compared with the endovascular group. The rebleeding rate was significantly lower in the microsurgery group (OR = 14.90; 95% CI, 1.90-117.13; P = 0.00085). No patient required retreatment in the microsurgery group, whereas 23 patients required retreatment in the endovascular group (P < 0.0001). There was no significant difference regarding the low direct mortality rate of coil embolization versus microsurgical clipping (P = 0.21).

CONCLUSIONS

Microsurgical clipping shows a lower rate of treatment-associated complications and a higher occlusion rate of ruptured intracranial aneurysms than coil embolization. The individual evaluation and decision process for choice of treatment modality in this study is very effective.

Cerebral Infarction After Aneurysmal Subarachnoid Hemorrhage

Predictors for cerebral infarction, an important cause of poor outcome after aneurysmal subarachnoid hemorrhage (SAH), were examined. This study used data from the Prospective Registry of Subarachnoid Aneurysms Treatment (PRESAT) cohort, which included 579 patients whose ruptured aneurysms were treated with either clipping or coiling within 12 days of onset. Patient, clinical, radiographic, and treatment variables associated with cerebral infarction were determined. Ruptured aneurysms were clipped in 282 patients and coiled in 297 patients. Cerebral infarction occurred in 162 patients (28.0 %): 101 patients by cerebral vasospasm, 34 patients by clipping, and 33 patients by coiling. Univariate analyses showed that significant factors associated with cerebral infarction development were Fisher computed tomography (CT) group 3 on admission, premature aneurysm rupture during clipping procedure, cerebrospinal fluid drainage, symptomatic vasospasm, endovascular treatment for vasospasm, and shunt-dependent hydrocephalus. Multivariable logistic regression analyses showed that cerebral infarction was significantly associated with Fisher CT group 3 on admission, larger aneurysm dome size, ruptured posterior circulation aneurysms, premature aneurysm rupture during clipping procedure, symptomatic vasospasm, and infection, while endovascular treatment for vasospasm significantly decreased the development of cerebral infarction. The most important potentially treatable factor associated with cerebral infarction was symptomatic vasospasm.

Neuroradiologic Diagnosis of Minor Leak prior to Major SAH: Diagnosis by T1-FLAIR Mismatch

BACKGROUND AND PURPOSE

In major SAH, the only method to diagnose a preceding minor leak is to ascertain the presence of a warning headache by interview; however, poor clinical condition and recall bias can cause inaccuracy. We devised a neuroradiologic method to diagnose previous minor leak in patients with SAH and attempted to determine whether warning (sentinel) headaches were associated with minor leaks before major SAH.

MATERIALS AND METHODS

We retrospectively evaluated 127 patients who were admitted with SAH within 48 hours of ictus. Previous minor leak before major SAH was defined as T1WI-detected clearly bright hyperintense subarachnoid blood accompanied by SAH blood on FLAIR images that was distributed over a larger area than bright hyperintense subarachnoid blood on T1WI (T1-FLAIR mismatch).

RESULTS

The incidence of warning headache before SAH was 11.0% (14 of 127 patients, determined by interview). The incidence of T1-FLAIR mismatch (neuroradiologic diagnosis of minor leak before major SAH) was 33.9% (43 of 127 patients). Of the 14 patients with warning headache, 13 had a minor leak diagnosed by T1-FLAIR mismatch at the time of admission. Variables identified by multivariate analysis as significantly associated with minor leak diagnosed by T1-FLAIR mismatch included 80 years of age or older, rebleeding after admission, intracerebral hemorrhage on CT, and mRS scores of 3-6.

CONCLUSIONS

We conclude that warning headaches diagnosed by interview are not a product of recall bias but are the result of actual leaks from aneurysms.

Redefining secondary injury after subarachnoid hemorrhage in light of multimodal advanced neuroimaging, intracranial and transcranial neuromonitoring: beyond vasospasm

The classic idea that arterial narrowing, called vasospasm (VSP), represents the hallmark of secondary injury after subarachnoid hemorrhage, has been challenged. The more complex and pleiotropic pathophysiological repercussions from the irruption of arterial blood into the subarachnoid layers go beyond the ascribed VSP. Putting adjectives in front of this term, such as "symptomatic," "microdialytic," or "angiographic" VSP, is misleading. Delayed cerebral ischemia (DCI) is a better term but remains restrictive to severe hypoperfusive injury and neglects oligemia, edema, and metabolic nonischemic injuries. In recognition of these issues, the international conference on VSP integrated "neurovascular events" into its name ( www.vasospasm2013.com ) and a multidisciplinary research group was formed in 2010 to study subgroups of DCI/VSP and their respective significance.In three parts, this tiered article provides a broader definitional envelope for DCI and secondary neurovascular insults after SAH, with a rubric for each subtype of delayed neuronal dysfunction. First, it pinpoints the need for nosologic precision and covers current terminological inconsistency. Then, it highlights the input of neuroimaging and neuromonitoring in defining secondary injurious processes. Finally, a new categorization of deteriorating patients is proposed, going beyond a hierarchical or dichotomized definition of VSP/DCI, and common data elements are suggested for future trials.

Aneurysmal subarachnoid haemorrhage from a neuroimaging perspective

Neuroimaging is a key element in the management of patients suffering from subarachnoid haemorrhage (SAH). In this article, we review the current literature to provide a summary of the existing neuroimaging methods available in clinical practice. Noncontrast computed tomography is highly sensitive in detecting subarachnoid blood, especially within 6 hours of haemorrhage. However, lumbar puncture should follow a negative noncontrast computed tomography scan in patients with symptoms suspicious of SAH. Computed tomography angiography is slowly replacing digital subtraction angiography as the first-line technique for the diagnosis and treatment planning of cerebral aneurysms, but digital subtraction angiography is still required in patients with diffuse SAH and negative initial computed tomography angiography. Delayed cerebral ischaemia is a common and serious complication after SAH. The modern concept of delayed cerebral ischaemia monitoring is shifting from modalities that measure vessel diameter to techniques focusing on brain perfusion. Lastly, evolving modalities applied to assess cerebral physiological, functional and cognitive sequelae after SAH, such as functional magnetic resonance imaging or positron emission tomography, are discussed. These new techniques may have the advantage over structural modalities due to their ability to assess brain physiology and function in real time. However, their use remains mainly experimental and the literature supporting their practice is still scarce.