Peter B. Sporns

Computed Tomographic Blend Sign Is Associated With Computed Tomographic Angiography Spot Sign and Predicts Secondary Neurological Deterioration After Intracerebral Hemorrhage

Background and Purpose— Significant early hematoma growth in patients with intracerebral hemorrhage is an independent predictor of poor functional outcome. Recently, the novel blend sign (BS) has been introduced as a new imaging sign for predicting hematoma growth in noncontrast computed tomography. Another parameter predicting increasing hematoma size is the well-established spot sign (SS) visible in computed tomographic angiography. We, therefore, aimed to clarify the association between established SS and novel BS and their values predicting a secondary neurological deterioration. Methods— Retrospective study inclusion criteria were (1) spontaneous intracerebral hemorrhage confirmed on noncontrast computed tomography and (2) noncontrast computed tomography and computed tomographic angiography performed on admission within 6 hours after onset of symptoms. We defined a binary outcome (secondary neurological deterioration versus no secondary deterioration). As secondary neurological deterioration, we defined (1) early hemicraniectomy under standardized criteria or (2) secondary decrease of Glasgow Coma Scale of >3 points, both within the first 48 hours after symptom onset. Results— Of 182 patients with spontaneous intracerebral hemorrhage, 37 (20.3%) presented with BS and 39 (21.4%) with SS. Of the 81 patients with secondary deterioration, 31 (38.3%) had BS and SS on admission. Multivariable logistic regression analysis identified hematoma volume (odds ratio, 1.07 per mL; P⩽0.001), intraventricular hemorrhage (odds ratio, 3.08; P=0.008), and the presence of BS (odds ratio, 11.47; P⩽0.001) as independent predictors of neurological deterioration. Conclusions— The BS, which is obtainable in noncontrast computed tomography, shows a high correlation with the computed tomographic angiography SS and is a reliable predictor of secondary neurological deterioration after spontaneous intracerebral hemorrhage.

Ischemic Stroke: What Does the Histological Composition Tell Us About the Origin of the Thrombus?

Background and Purpose— The introduction of stent retrievers allows for a complete extraction and histological analysis of human thrombi. Ischemic stroke is a major health issue, and differentiation of underlying causes is highly relevant to prevent recurrent stroke. Therefore, histopathologic analysis of the embolic clots after removal may provide valuable information about underlying pathologies. This study analyzes histological clot composition and aims to identify specific patterns that might help to distinguish causes of ischemic stroke. Methods— Patients with occlusion of the carotid-T or middle cerebral artery who underwent thrombectomy at our university medical center between December 2013 and February 2016 were included. Samples were histologically analyzed (hematoxylin and eosin, Elastica van Gieson, and Prussian blue), additionally immunohistochemistry for CD3, CD20, and CD68/KiM1P was performed. These data, along with additional clinical and interventional parameters, were compared for different stroke subtypes, as defined by the TOAST (Trial of Org 10172 in Acute Stroke Treatment) classification. Results— One hundred eighty-seven patients were included, of these, in 77 patients, cardioembolic; in 46 patients, noncardioembolic; and in 64 patients, cryptogenic pathogenesis was determined. Cardioembolic thrombi had higher proportions of fibrin/platelets (P=0.027), less erythrocytes (P=0.005), and more leucocytes (P=0.026) than noncardioembolic thrombi. We observed a strong overlap of cryptogenic strokes and cardioembolic strokes concerning thrombus histology. The immunohistochemical parameters CD3, CD20, and CD68/KiM1P showed no statistically noticeable differences between stroke subtypes. Conclusions— Histological thrombus features vary significantly according to the underlying cause and may help to differentiate between cardioembolic and noncardioembolic stroke. In addition, our study supports the hypothesis that most cryptogenic strokes have a cardioembolic cause.

Comparison of Spot Sign, Blend Sign and Black Hole Sign for Outcome Prediction in Patients with Intracerebral Hemorrhage

Background and Purpose Blend sign (BS) and black hole sign (BHS) on non-contrast computed tomography (NCCT) and spot sign (SS) on CT-angiography (CTA) are indicators of early hematoma expansion in spontaneous intracerebral hemorrhage (ICH). However, their independent contributions to outcome have not been well explored. Methods In this retrospective study, inclusion criteria were: 1) spontaneous ICH and 2) NCCT and CTA performed on admission within 6 hours after onset of symptoms. Discharge outcome was dichotomized as good (modified Rankin Scale [mRS] 0-3) and poor (mRS 4-6) outcomes. The impacts of BHS, BS and SS on outcome were assessed in univariate and multivariable logistic regression models. Results Of 182 patients with spontaneous ICH, 26 (14.3%) presented with BHS, 37 (20.3%) with BS and 39 (21.4%) with SS. There was a substantial correlation between SS and BS (κ=0.701) and a moderate correlation between SS and BHS (κ=0.424). In univariable logistic regression, higher baseline hematoma volume (P<0.001), intraventricular hemorrhage (P=0.002) and the presence of BHS/BS/SS (all P<0.001) on admission CT scan were associated with poor outcome. Multivariable analysis identified intraventricular haemorrhage (odds ratio [OR] 2.22 per mL, P=0.022), baseline hematoma volume (OR 1.03 per mL, P<0.001) and SS on CTA (OR 11.43, P<0.001) as independent predictors of poor outcome, showing that SS compared to BS and BHS was more powerful to predict poor outcome. Conclusions The NCCT BHS and BS are correlated with the CTA SS and are reliable predictors of poor outcome in patients with ICH. Of the CT variables indicating early hematoma expansion, SS on CTA was the most reliable outcome predictor. However, given their correlation with SS on CTA, BS and BHS on NCCT can be useful for predicting outcome if CTA is not obtainable.

Computed Tomography Perfusion Improves Diagnostic Accuracy in Acute Posterior Circulation Stroke.

Background and Purpose: Computed tomography perfusion (CTP) has a high diagnostic value in the detection of acute ischemic stroke in the anterior circulation. However, the diagnostic value in suspected posterior circulation (PC) stroke is uncertain, and whole brain volume perfusion is not yet in widespread use. We therefore studied the additional value of whole brain volume perfusion to non-contrast CT (NCCT) and CT angiography source images (CTA-SI) for infarct detection in patients with suspected acute ischemic PC stroke. Methods: This is a retrospective review of patients with suspected stroke in the PC in a database of our stroke center (n = 3,011) who underwent NCCT, CTA and CTP within 9 h after stroke onset and CT or MRI on follow-up. Images were evaluated for signs and pc-ASPECTS locations of ischemia. Three imaging models - A (NCCT), B (NCCT + CTA-SI) and C (NCCT + CTA-SI + CTP) - were compared with regard to the misclassification rate relative to gold standard (infarction in follow-up imaging) using the McNemars test. Results: Of 3,011 stroke patients, 267 patients had a suspected stroke in the PC and 188 patients (70.4%) evidenced a PC infarct on follow-up imaging. The sensitivity of Model C (76.6%) was higher compared with that of Model A (21.3%) and Model B (43.6%). CTP detected significantly more ischemic lesions, especially in the cerebellum, posterior cerebral artery territory and thalami. Conclusions: Our findings in a large cohort of consecutive patients show that CTP detects significantly more ischemic strokes in the PC than CTA and NCCT alone.

CT versus MR Techniques in the Detection of Cervical Artery Dissection

Spontaneous cervical artery dissection (sCAD) is an important etiology of juvenile stroke. The gold standard for the diagnosis of sCAD is convential angiography. However, magnetic resonance imaging (MRI)/MR angiography (MRA) and computed tomography (CT)/CT angiography (CTA) are frequently used alternatives. New developments such as multislice CT/CTA have enabled routine acquisition of thinner sections with rapid imaging times. The goal of this study was to compare the capability of recent developed 128‐slice CT/CTA to MRI/MRA to detect radiologic features of sCAD.

Impact of the Implementation of Thrombectomy with Stent Retrievers on the Frequency of Hemicraniectomy in Patients with Acute Ischemic Stroke.

BackgroundThe increasing use of endovascular treatments has led to higher recanalization rates and better clinical outcomes compared with intravenous thrombolysis alone. Stent retrievers represent the latest development for recanalization of large vessel occlusions. Decompressive hemicraniectomy has proved beneficial in patients suffering from rising intracranial pressure after malignant stroke.Aims and/or HypothesisWe investigated the effect of the implementation of stent retriever treatment on the frequency of hemicraniectomy as a surrogate marker for infarct size and thus for poor neurological outcome.MethodsPatients with acute ischemic stroke were retrospectively studied. We compared the frequency of hemicraniectomy following proximal artery occlusion of the internal carotid artery and middle cerebral artery main stem in the years before (2009 and 2010) and after (2012 and 2013) introducing stent retrievers.ResultsOverall, 497 patients with proximal arterial occlusion were included in the study. Of 253 patients admitted in the years 2009 and 2010 44 (17.4 %) and of 244 patients admitted in 2012 and 2013, 20 (8.2 %) received a hemicraniectomy. This decrease in the proportion of hemicraniectomies was statistically significant (p < 0.01).ConclusionsThe findings in this study illustrate a significantly reduced rate of hemicraniectomies in patients with proximal artery occlusions after implementation of thrombectomy with stent retriever. Hereby, we could show a significant reduction of malignant infarctions after thrombectomy with stent retriever.

Simpson grade IV resections of skull base meningiomas: does the postoperative tumor volume impact progression?

Surgery for skull base meningiomas is frequently limited to subtotal resection (Simpson grade IV) to preserve critical anatomical structures and neurological function. On the other hand, the relevance of a maximum resection for tumor progression is increasingly discussed. In this context, we recently demonstrated an increased risk of tumor progression after Simpson grade IV resection in skull base meningiomas, while prognosis was similar after grade I–III surgery [1]. However, “Simpson grade IV resection” as classified by the neurosurgeon is imprecise and the influence of the amount of meningioma remnants on progression, especially in skull base lesions, is largely unknown. We therefore investigated the impact of the postoperative tumor volume on progression in patients from the same series who underwent Simpson grade IV resections of primary diagnosed skull base meningiomas. The extent of resection according to the Simpson classification had been obtained from operative reports in each case. Data recovery and follow-up has been described previously [1]. For this study, tumor volume on initial postoperative imaging performed within 12 months after surgery was segmented using an established semi-automatic technique (Medical Imaging Toolkit; MITK, Istituto di Calcolo ad Alte Prestazioni, Napoli, Italy) by a radiologist blinded to any follow-up data (Fig. 1). Follow-up imaging was analyzed by a team of at least one neurosurgeon and one (neuro-)radiologist and progression was defined in case of any increase of tumor size greater than CT or MRI resolution capacity [1]. Associations between the postoperative tumor volumes and progression were then investigated in statistical analyses. Using this approach, eligible postoperative imaging and follow-up data of 49 of the 62 patients who underwent Simpson grade IV resection in our previous series [1] were available (79%). Clinical, histopathological and radiological data are summarized in Table 1. Surgery was performed between 2007 and 2015. Imaging was performed after a median of 3 months after surgery (range 0–12 months) and included contrast-enhanced magnet resonance imaging (MRI) in 45 individuals (92%) and, due to contraindications against MRI, computed tomography (CT) scans in 4 of 49 patients (8%), respectively. Median postoperative tumor volume was 2.99 cubic centimeter (ccm, range .02–67.08 ccm) and significantly varied among the different tumor locations. Hence, median tumor volume was .75, 9.36, 3.81 and 8.51 ccm in sphenoid ridge, cerebello pontine angle, petroclival/clival and foramen magnum meningiomas and .16 ccm in tumors of other skull base locations (p = .008, Kruskal–Wallis-H test). Duration of surgery positively correlated with postoperative tissue volume (p = .001, Pearson test). Postoperative tumor volume was independent of the use of intraoperative neuronavigation (p = .515) but was higher after surgeries in which neurophysiological monitoring was used (p = .009, Mann–Whitney-U test). Within a median follow-up period of 41 months (range 1–96 months), tumor progression was observed in 13 patients (27%) after a median progression free interval (PFI) of 24 months (range 4–50 months). During follow-up, 15 of 47 patients (32%) with available data received adjuvant radiation therapy prior to progression after a median of 9 months (range 3–96 month), while 32 individuals were followed-up without irradiation. Among those, preoperative irradiation had been performed in 2 individuals (4%). Thus, analyzes included 30 irradiation-naive patients until the date of progression. None of the patients had received irradiation prior to initial postoperative MRI. Median PFI was 14 months in atypical meningiomas but was not reached * Benjamin Brokinkel benjamin.brokinkel@ukmuenster.de

Imaging-based outcome prediction in patients with intracerebral hemorrhage

Besides the established spot sign in computed tomography angiography (CTA), recently investigated imaging predictors of hematoma growth in noncontrast computed tomography (NCCT) suggest great potential for outcome prediction in patients with intracerebral hemorrhage (ICH). Secondary hematoma growth is an appealing target for therapeutic interventions because in contrast to other determined factors, it is potentially modifiable. Even more initial therapy studies failed to demonstrate clear therapeutic benefits, there is a need for an effective patient selection using imaging markers to identify patients at risk for poor outcome and thereby tailor individual treatments for every patient. Hence, this review gives an overview about the current literature on NCCT imaging markers for neurological outcome prediction and aims to clarify the association with the established spot sign. Moreover, it demonstrates the clinical impact of these parameters and gives a roadmap for future imaging research in patients with intracerebral hemorrhage.

Ischemic Stroke: Histological Thrombus Composition and Pre-Interventional CT Attenuation Are Associated with Intervention Time and Rate of Secondary Embolism

Background and Purpose: The introduction of stent retrievers has made the complete extraction and histological analysis of human thrombi possible. A number of large randomized trials have proven the efficacy of thrombectomy for ischemic stroke; however, thrombus composition could have an impact on the efficacy and risk of the intervention. We therefore investigated the impact of histologic thrombus features on interventional outcome and procedure-related embolisms. For a pre-interventional estimation of histologic features and outcome parameters, we assessed the pre-interventional CT attenuation of the thrombi. Methods: We prospectively included all consecutive patients with occlusion of the middle cerebral artery who underwent thrombectomy between December 2013 and February 2016 at our university medical center. Samples were histologically analyzed (H&E, Elastica van Gieson, Prussian blue); additionally, immunohistochemistry for CD3, CD20, and CD68/KiM1P was performed. Main thrombus components (fibrin, erythrocytes, and white blood cells) were determined and compared to intervention time, frequency of secondary embolisms, as well as additional clinical and interventional parameters. Additionally, we assessed the pre-interventional CT attenuation of the thrombi in relation to the unaffected side (rHU) and their association with histologic features. Results: One hundred eighty patients were included; of these, in 168 patients (93.4%), complete recanalization was achieved and 27 patients (15%) showed secondary embolism in the control angiogram. We observed a significant association of high amounts of fibrin (p < 0.001), low percentage of red blood cells (p < 0.001), and lower rHU (p < 0.001) with secondary embolism. Higher rHU values were significantly associated with higher amounts of fibrin (p ≤ 0.001) and low percentage of red blood cells (p ≤ 0.001). Additionally, high amounts of fibrin were associated with longer intervention times (p ≤ 0.001), whereas thrombi with high amounts of erythrocytes correlated with shorter intervention times (p ≤ 0.001). ROC analysis revealed reliable prediction of secondary embolisms for low rHU (AUC = 0.746; p ≤ 0.0001), low amounts of RBC (AUC = 0.764; p ≤ 0.0001), and high amounts of fibrin (AUC = 0.773; p ≤ 0.0001). Conclusions: Fibrin-rich thrombi with low erythrocyte percentage are significantly associated with longer intervention times. Embolisms in the thrombectomy process occur more often in thrombi with a small fraction of red blood cells and a low CT-density, suggesting a higher fragility of these thrombi.

Undetected Dural Leaks Complicated by Accidental Drainage of Cerebrospinal Fluid (CSF) can Lead to Severe Neurological Deficits.

PURPOSE Intracranial hypotension has been reported as a complication of accidental drainage after surgical treatment in several cases. Application of negative pressure systems (wound drains, VAC(®)-therapy, chest tube drainage) had typically led to severe intracranial hypotension including intracranial hemorrhage and tonsillar herniation. In the last year the authors observed 2 cases of accidental spinal drainage of CSF in patients with neurological deficits, regressing after reduction of the device suction. MATERIAL AND METHODS We conducted a systematic PubMed-based research of the literature to study the variety and frequency of the reported symptoms from 1st of January 1980 until 1st of October 2015. RESULTS Reviewing the literature 24 relevant citations including 27 reported cases of posttraumatic or postoperative loss of CSF leading to neurological symptoms were identified. All 15 reported cases in which a negative pressure suction device had been applied showed severe neurological and radiological symptoms such as coma or brain herniation and intracranial hemorrhage. In all cases patients recovered rapidly after removal of the suction device. Milder symptoms were observed in the patients without negative pressure suction, mainly only presenting with headaches or cranial nerve involvement.Additionally, we give an overview about current recommendations regarding cranial and spinal imaging to rule out dural laceration and cranial hypotension. CONCLUSION Patients with dural laceration complicated by accidental drainage of CSF can present with life-threatening conditions. Increasing use of negative pressure suction devices makes the reported condition an important differential diagnosis. A precise radiological examination can help to rule out dural laceration and intracranial hypotension. KEY POINTS • Undetected dural laceration complicated by negative pressure suction drains can induce life-threatening symptoms.• Increasing use of negative pressure suction devices makes the reported condition an important differential diagnosis for radiologists Citation Format: • Sporns PB, Schwindt W, Cnyrim CD et al. Undetected Dural Leaks Complicated by Accidental Drainage of Cerebrospinal Fluid (CSF) can Lead to Severe Neurological Deficits. Fortschr Röntgenstr 2016; 188: 451 - 458.