Dual-energy Computed Tomography (DECT) predicts the efficacy of contrast medium extravasation and secondary cerebral hemorrhage after stent thrombectomy in acute ischemic cerebral infarction.

To prospective research the efficacy of dual-energy computed tomography (DECT) in predicting contrast medium extravasation and secondary cerebral hemorrhage after stent thrombectomy in acute ischemic cerebral infarction. Ninety-two patients with acute ischemic stroke who underwent intra-arterial thrombolysis in our hospital from December 2019 to January 2022 have opted as the study subjects. DECT was performed immediately after stent thrombectomy. Images were generated through the image workstation and routine diagnosis was performed 24 hours after the operation. To analyze the diagnostic value of To analyze the diagnostic value of DECT, and to explore the diagnostic status of lesions with hemorrhagic transformation or increased hemorrhage and their correlation with iodine concentration. (1) 68 situations were confirmed, 56 positive and 12 negative with detection rates of 10.71% for hemorrhage, 75.00% for contrast agent extravasation, and 14.29% for extravasation combined with hemorrhage; (2) DECT diagnosed 8 cases of postoperative bleeding and 44 cases of extravasation of contrast media and 4 cases of extravasation of contrast media with hemorrhage ; The accuracy of DECT in diagnosing postoperative hemorrhage was 96.43%. The accuracy of diagnosis of extravasation was 96.43%. (3) The mean iodine concentration of lesions with increased hemorrhage or hemorrhagic transformation was higher compared to those without; (4) There was a correlation between hemorrhagic transformation or increased hemorrhage and iodine concentration. Dual-energy CT (DECT) can accurately distinguish the extravasation of contrast agent and secondary cerebral hemorrhage, and can predict the increased bleeding and bleeding transformation, with good diagnostic value and good predictive efficacy.

Post-endovascular therapy contrast extravasation in the mesial temporal region on dual-energy CT is associated with outcome in acute ischemic stroke patients.

PURPOSE: Pre- and post-endovascular treatment (EVT) imaging may aid in predicting functional outcomes in acute middle cerebral artery (MCA) ischemic stroke. Low post-EVT contrast extravasation (CE)-ASPECTS is associated with poor functional outcomes. Besides the MCA regions included in the ASPECTS score, CE may be seen in the mesial temporal (MT) region. In this study, we investigated the frequency and prognostic implication of MT-CE in acute ischemic stroke patients. METHODS: Patients with an acute ischemic stroke due to anterior large vessel occlusion who received EVT and post-EVT DECT between 2010 and 2019 were included. Iodine overlay maps of DECT were assessed for the occurrence of CE, using the ASPECTS for occurrence in the MCA region and, calculating a CE-ASPECTS, for whether the MT region was involved. Multivariable linear and logistic regression were used to assess the relationship between involvement of MT-CE and 24-48h NIHSS, mRS, and mortality on a multiple imputed dataset. All models were adjusted significant variables in univariate analyses and for total CE-ASPECTS. RESULTS: 501/651 patients met the inclusion criteria. MT-CE occurred in 97 (19 %) patients, and was more often present in patients with internal carotid artery occlusions. MT-CE was associated with higher NIHSS scores at 24-hours (aß 2.2, 95 % CI 0.09-4.31), with increased risk of higher mRS scores (acOR 1.88, 95 % CI 1.16-3.06), and with increased risk of mortality (aOR 2.12, 95 % CI 1.16-3.86). CONCLUSION: MT-CE is a common finding on post-EVT DECT and is an independent predictor for worse functional outcomes.

Predictors and pathways of in-hospital mortality in active vascular contrast extravasation detected on abdominopelvic CT.

OBJECTIVES: This study aimed to identify factors influencing in-hospital mortality in adult patients with active vascular contrast extravasation (AVCE) on abdominopelvic computed tomography (CT). METHODS: All consecutive patients with AVCE detected on CT between January 2019 and May 2022 were retrospectively included. Their data were compared through uni- and multivariable analyses between patients with and without in-hospital mortality. Path analysis was utilized to clarify the relationships among factors affecting mortality. RESULTS: There were 272 patients (60.2 ± 19.4 years, 150 men) included, of whom 70 experienced in-hospital mortality. Multivariable analysis revealed nonsurgery, chronic kidney disease (CKD) stage 4-5 or dialysis, prolonged partial thromboplastin time (PTT), minimum AVCE length > 8 mm, and a lower rate of packed red cell (PRC) transfusion were identified as independent predictors of in-hospital mortality (p = 0.005-0.048). Path analysis demonstrated direct influences of CKD4-5 or dialysis, prolonged PTT, and minimum AVCE length on mortality (coefficients 0.525-0.616; p = 0.009 to < 0.001). PRC transfusion impacted mortality through nonsurgery (coefficient 0.798, p = 0.003) and intensive care unit (ICU) admission (coefficients 0.025, p = 0.016), leading to subsequent death. Three AVCE spaces (free, loose, and tight) defined on CT were not directly associated with in-hospital mortality. CONCLUSION: In adults with AVCE on CT, AVCE size had a direct independent influence on mortality, highlighting the critical role of radiologists in detecting and characterizing this finding. Additionally, CKD4-5 or dialysis and prolonged PTT also directly influenced mortality, while the lower rate of PRC transfusion impacted mortality through nonsurgery and ICU admission. CLINICAL RELEVANCE STATEMENT: In patients with active vascular contrast extravasation (AVCE) on abdominopelvic CT, larger AVCE directly increased in-hospital mortality. Radiologists' detection and characterization of this finding is crucial, along with recognizing factors like CKD4-5, dialysis, and prolonged PTT to improve patient outcomes. KEY POINTS: Several factors independently predicted in-hospital mortality in patients with abdominopelvic AVCE. Extravasation length > 8 mm was the only imaging marker predictive of in-hospital mortality. Non-imaging factors correlated with in-hospital mortality, and PRC transfusion impacted mortality through nonsurgery and ICU admission pathways.

Pelvic fractures in blunt trauma patients: A comparative study.

BACKGROUND: Pelvic fractures (PF) with concomitant injuries are on the rise due to an increase of high-energy trauma. Increase of the elderly population with age related comorbidities further complicates the management. Abdominal organ injuries are kindred with PF due to the proximity to pelvic bones. Presence of contrast blush (CB) on computed tomography in patients with PF is considered a sign of active bleeding, however, its clinical significance and association with outcomes is debatable. AIM: To analyze polytrauma patients with PF with a focus on the geriatric population, co-injuries and the value of contrast blush. METHODS: This retrospective cohort study included 558 patients with PF admitted to level 1 trauma center (01/2017-01/2023). Analyzed variables included: Age, sex, mechanism of injury (MOI), injury severity score (ISS), Glasgow coma scale (GCS), abbreviated injury scale (AIS), co-injuries, transfusion requirements, pelvic angiography, embolization, laparotomy, orthopedic pelvic surgery, intensive care unit and hospital lengths of stay, discharge disposition and mortality. The study compared geriatric and non-geriatric patients, patients with and without CB and abdominal co-injuries. Propensity score matching was implemented in comparison groups. RESULTS: PF comprised 4% of all trauma admissions. 89 patients had CB. 286 (52%) patients had concomitant injuries including 93 (17%) patients with abdominal co-injuries. Geriatric patients compared to non-geriatric had more falls as MOI, lower ISS and AIS pelvis, higher GCS, less abdominal co-injuries, similar CB and angio-embolization rates, less orthopedic pelvic surgeries, shorter lengths of stay and higher mortality. After propensity matching, orthopedic pelvic surgery rates remained lower (8% vs 19%, P < 0.001), hospital length of stay shorter, and mortality higher (13% vs 4%, P < 0.001) in geriatric patients. Out of 89 patients with CB, 45 (51%) were embolized. After propensity matching, patients with CB compared to without CB had more pelvic angiography (71% vs 12%, P < 0.001), higher embolization rates (64% vs 22%, P = 0.02) and comparable mortality. CONCLUSION: Half of the patients with PF had concomitant co-injuries, including abdominal co-injuries in 17%. Similarly injured geriatric patients had higher mortality. Half of the patients with CB required an embolization.

Relationship between extravascular leakage and clinical outcome on computed tomography of isolated traumatic brain injury.

Aim: This study investigated whether contrast extravasation on computed tomography (CT) angiography in patients with traumatic brain injury (TBI) is associated with death or surgical procedures. Methods: Patients over 18 years old, directly brought in by ambulance with an isolated head injury and confirmed to have acute intracranial hemorrhage on a CT scan upon admission between 2010 and 2020, were included. The primary outcome was mortality, and the secondary outcome was neurosurgical procedures performed from admission to discharge from the intensive care unit. Multivariable logistic regression analyses were performed to evaluate the association between these outcomes and contrast extravasation. Results: The analysis included 188 patients with a median age of 65 years, 123 men (65.4%), 34 deaths (18.1%), and 91 surgeries (48.4%). Among the 66 patients with contrast extravasation, 22 (33.3%) died and 47 (71.2%) required surgery. Among the 122 patients with no contrast extravasation, 12 (9.8%) died, and 44 (36.1%) required surgery. The presence or absence of extravascular leakage was associated with death (odds ratio, 3.6 [95% CI: 1.2-12.2]) and surgery (odds ratio, 7.6 [95% CI: 2.5-22.7]). Conclusion: Contrast extravasation was associated with mortality and performance of surgery in patients with an isolated head injury.

The correlation between CT perfusion deficits and immediate post-endovascular treatment contrast extravasation on dual energy CT in acute ischemic stroke patients.

PURPOSE: After endovascular therapy (EVT) for ischemic stroke, post-EVT CT imaging often shows areas of contrast extravasation (CE) caused by blood brain barrier disruption (BBBD). Before EVT, CT-perfusion (CTP) can be used to estimate salvageable tissue (penumbra) and irrevocably damaged infarction (core). In this study, we aimed to correlate CTP deficits to CE, as a surrogate marker for BBBD, after EVT for ischemic stroke. METHODS: In this single center study, EVT patients between 2010 and 2020 in whom both CTP at baseline and DECT post-EVT was performed were included. The presence of core and penumbra on CTP was assessed per ASPECTS region, resulting in a CTP-ASPECTScore and a CTP-ASPECTScore+penumbra. Likewise, CE on DECT was scored per ASPECTS region, resulting in a CE-ASPECTS. Correlation was assessed using Kendall's tau correlation and positive predictive values (PPV) were calculated per ASPECTS region. Bland-Altman plots were created to visualize the agreement between the two scores. RESULTS: 194 patients met our inclusion criteria. The median core and penumbra were 8 cc (IQR 1-25) and 103 cc (IQR 68-141), respectively. The median CTP-ASPECTScore, CTP-ASPECTScore+penumbra, and CE-ASPECTS were 7 (IQR 4-9), 3 (IQR 1-4), and 6 (IQR 4-9), respectively. The correlation between CTP-ASPECTScore and CE-ASPECTS was τ = 0.21, P <.001, and τ = 0.13, P =.02 between CTP-ASPECTScore+penumbra and CE-ASPECTS. Bland-Altman plots showed a mean difference (CTP-ASPECTS minus CE-ASPECTS) of 0.27 (95 %CI -6.7-7.2) for CTP-ASPECTScore and -3.2 (95 %CI -9.7-3.2) for CTP-ASPECTScore+penumbra. The PPVs of the CTP-ASPECTScore and CTP-ASPECTScore+penumbra were highest for the basal ganglia. CONCLUSION: There is a weak although significant correlation between pre-EVT CTP-ASPECTS and post-EVT CE-ASPECTS. The weak correlation may be attributed to various imaging limitations as well as patient related factors.

CT Texture-Based Nomogram in Ischemic Stroke to Differentiate Intracerebral Hemorrhage from Contrast Extravasation after Thrombectomy.

INTRODUCTION: Post-thrombectomy intraparenchymal hyperdensity (PTIH) in patients with acute ischemic stroke is a common CT sign, making it difficult for physicians to distinguish intracerebral hemorrhage in the early post-thrombectomy period. The aim of this study was to develop an effective model to differentiate intracerebral hemorrhage from contrast extravasation in patients with PTIH. METHODS: We retrospectively collected information on patients who underwent endovascular thrombectomy at two stroke centers between August 2017 and January 2023. A total of 222 patients were included in the study, including 118 patients in the development cohort, 52 patients in the internal validation cohort, and 52 patients in the external validation cohort. The nomogram was constructed using R software based on independent predictors derived from the multivariate logistic regression analysis, including clinical factors and CT texture features extracted from hyperdense areas on CT images. The performance and accuracy of the derived nomogram were assessed by the area under the receiver operating characteristic curve (AUC-ROC) and calibration curves. Additionally, decision curve analysis was conducted to appraise the clinical utility of the nomogram. RESULTS: Our nomogram was derived from two clinical factors (ASPECT score and onset to reperfusion time) and two CT texture features (variance and uniformity), with AUC-ROC of 0.943, 0.930, and 0.937 in the development, internal validation, and external validation cohorts, respectively. Furthermore, the calibration plot exhibited a strong agreement between the predicted outcome and the actual outcome. In addition, the decision curve analysis revealed the clinical utility of the nomogram in accurately predicting hemorrhage in patients with PTIH. CONCLUSION: The developed nomogram, based on clinical factors and CT texture features, proves to be effective in distinguishing intracerebral hemorrhage from contrast extravasation in patients with PTIH.

Association of Contrast Extravasation Grade With Massive Transfusion in Pediatric Blunt Liver and Spleen Injuries: A Multicenter Retrospective Cohort Study.

BACKGROUND: This study aimed to assess whether the grade of contrast extravasation (CE) on CT scans was associated with massive transfusion (MT) requirements in pediatric blunt liver and/or spleen injuries (BLSI). METHODS: This multicenter retrospective cohort study included pediatric patients (≤16 years old) who sustained BLSI between 2008 and 2019. MT was defined as transfusion of all blood products ≥40 mL/kg within the first 24 h of admission. Associations between CE and MT requirements were assessed using multivariate logistic regression analysis with cluster-adjusted robust standard errors to calculate the adjusted odds ratio (AOR). RESULTS: A total of 1407 children (median age: 9 years) from 83 institutions were included in the analysis. Overall, 199 patients (14 %) received MT. CT on admission revealed that 54 patients (3.8 %) had CE within the subcapsular hematoma, 100 patients (7.1 %) had intraparenchymal CE, and 86 patients (6.1 %) had CE into the peritoneal cavity among the overall cohort. Multivariate analysis, adjusted for age, sex, age-adjusted shock index, injury severity, and laboratory and imaging factors, showed that intraparenchymal CE and CE into the peritoneal cavity were significantly associated with the need for MT (AOR: 2.50; 95 % CI, 1.50-4.16 and AOR: 4.98; 95 % CI, 2.75-9.02, respectively both p < 0.001). The latter significant association persisted in the subgroup of patients with spleen and liver injuries. CONCLUSION: Active CE into the free peritoneal cavity on admission CT was independently associated with a greater probability of receiving MT in pediatric BLSI. The CE grade may help clinicians plan blood transfusion strategies. LEVEL OF EVIDENCE: Level 4; Therapeutic/Care management.

The Association of the Spatial Location of Contrast Extravasation with Symptomatic Intracranial Hemorrhage after Endovascular Therapy in Acute Ischemic Stroke Patients.

BACKGROUND: Contrast extravasation (CE) on brain non-contrast computed tomography (NCCT) after endovascular therapy (EVT) is commonly present in patients with acute ischemic stroke (AIS). Substantial uncertainties remain about the relationship between the spatial location of CE and symptomatic intracranial hemorrhage (sICH). Therefore, this study aimed to evaluate this association. METHODS: We performed a retrospective screening on consecutive patients with AIS due to LVO (AIS-LVO) who had CE on NCCT immediately after EVT for anterior circulation large vessel occlusion (LVO). We used the Alberta stroke program early CT Score (ASPECTS) scoring system to estimate the spatial location of CE. Multivariable logistic regression was performed to achieve the risk factors of sICH. RESULTS: In this study, 115 of 153 (75.1%) anterior circulation AIS-LVO patients had CE on NCCT. After excluding 9 patients, 106 patients were enrolled in the final analysis. In multivariate regression analysis, atrial fibrillation (AF) (adjusted OR [aOR] 6.833, 95% confidence interval [CI] 1.331-35.081, P = 0.021) and CE-ASPECTS (aOR 0.602, 95% CI 0.411-0.882 P = 0.009) were associated with sICH. In subgroup analysis, CE at the internal capsule (IC) region was an independent risk factor for sICH (aOR 5.992, 95% CI 1.010-35.543 P < 0.05). These and conventional variables were incorporated as a predict model, with AUC of 0.899, demonstrating good discrimination and calibration for sICH in this study cohort. CONCLUSION: The spatial location of CE on NCCT immediately after EVT was an independent and strong risk factor for sICH in acute ischemic stroke patients.

Acute cerebral hemorrhage mimicking glioblastoma on intraoperative magnetic resonance imaging: A case report.

Intraoperative magnetic resonance imaging (iMRI) is important in neurosurgical practice, especially for glioma surgery. However, the well-reported possibility to mistake lesions for brain tumors (tumor mimics) with MRI also exists for iMRI. Here, we first report a case of glioblastoma with acute cerebral hemorrhage that mimicked a newly emerged brain tumor on iMRI. A 53-year-old man underwent a second surgery for recurrent glioblastoma. Intraoperatively, iMRI revealed a new, enhanced lesion near the resected area that was absent on preoperative MRI and difficult to differentiate from newly emerged tumors. Here, a recent preoperative MRI was helpful and the new lesion was actually a hematoma. Neurosurgeons must understand that, as acute intracerebral hemorrhaging can mimic brain tumors on iMRI, preoperative MRI should be conducted just before surgery to place iMRI findings in proper context and avoid unnecessary resections.

Early post-endovascular treatment contrast extravasation on dual-energy CT is associated with clinical and radiological stroke outcomes: A 10-year single-centre experience.

OBJECTIVE: To determine the association between early post-endovascular treatment (EVT) contrast extravasation (CE) on dual-energy CT (DECT) and stroke outcomes. METHODS: EVT records in 2010-2019 were screened. Exclusion criteria included the occurrence of immediate post-procedural intracranial haemorrhage (ICH). Hyperdense areas on iodine overlay maps were scored according to the Alberta Stroke Programme Early CT Score (ASPECTS), thus forming a CE-ASPECTS. Maximum parenchymal iodine concentration and maximum iodine concentration relative to the torcula were recorded. Follow-up imaging was reviewed for ICH. The primary outcome measure was the modified Rankin Scale (mRS) at 90 days. RESULTS: Out of 651 records, 402 patients were included. CE was found in 318 patients (79%). Thirty-five patients developed ICH on follow-up imaging. Fourteen ICHs were symptomatic. Stroke progression occurred in 59 patients. Multivariable regression showed a significant association between decreasing CE-ASPECTS and the mRS at 90 days (adjusted (a)cOR: 1.10, 95% CI: 1.03-1.18), NIHSS at 24-48 h (aß: 0.57, 95% CI: 0.29-0.84), stroke progression (aOR: 1.14, 95% CI: 1.03-1.26) and ICH (aOR: 1.21, 95% CI: 1.06-1.39), but not symptomatic ICH (aOR 1.19, 95% CI: 0.95-1.38). Iodine concentration was significantly associated with the mRS (acOR: 1.18, 95% CI: 1.06-1.32), NIHSS (aß: 0.68, 95% CI: 0.30-1.06), ICH (aOR: 1.37, 95% CI: 1.04-1.81) and symptomatic ICH (aOR: 1.19, 95% CI: 1.02-1.38), but not stroke progression (aOR: 0.99, 95% CI: 0.86-1.15). Results of the analyses with relative iodine concentration were similar and did not improve prediction. CONCLUSIONS: CE-ASPECTS and iodine concentration are both associated with short- and long-term stroke outcomes. CE-ASPECTS is likely a better predictor for stroke progression.

Comparison of outcomes of proximal versus distal and combined splenic artery embolization in the management of blunt splenic injury: a report of 202 cases from a single trauma center.

BACKGROUND: To compare the outcomes of blunt splenic injuries (BSI) managed with proximal (P) versus distal (D) versus combined (C) splenic artery embolization (SAE). METHODS: This retrospective study included patients with BSI who demonstrated vascular injuries on angiograms and were managed with SAE between 2001 and 2015. The success rate and major complications (Clavien-Dindo classification ≥ III) were compared between the P, D, and C embolizations. RESULTS: In total, 202 patients were enrolled (P, n = 64, 31.7%; D, n = 84, 41.6%; C, n = 54, 26.7%). The median injury severity score was 25. The median times from injury to SAE were 8.3, 7.0, and 6.6 h for the P, D, and C embolization, respectively. The overall haemostasis success rates were 92.6%, 93.8%, 88.1%, and 98.1% in the P, D, and C embolizations, respectively, with no significant difference (p = 0.079). Additionally, the outcomes were not significantly different between the different types of vascular injuries on angiograms or the materials used in the location of embolization. Splenic abscess occurred in six patients (P, n = 0; D, n = 5; C, n = 1), although it occurred more commonly in those who underwent D embolization with no significant difference (p = 0.092). CONCLUSIONS: The success rate and major complications of SAE were not significantly different regardless of the location of embolization. The different types of vascular injuries on angiograms and agents used in different embolization locations also did not affect the outcomes.

Severe spontaneous acute arterial subdural hematoma as an initial symptom of chronic myeloid leukemia.

Acute subdural hematoma (SDH) is a rare occurrence in chronic myeloid leukemia (CML) patients with only two cases reported in literature. However, sudden severe acute SDH caused by CML has not been reported on. Our patient was admitted for 'sudden unconsciousness for more than 1 hour'. Computed tomography (CT) angiography revealed a large amount of acute SDH on the left side. Physical exam showed the patient's left pupil was dilated and signs of cerebral herniation were present. The preoperative coagulation profile was normal. Emergency craniotomy for hematoma clearance and decompression was performed. During the surgery, a ruptured cerebral artery was located in the perisylvian region and hemostasis was achieved through electrocautery. Pre-operative white blood count was 58,100 cell/µl, with post-operative bone marrow examination、cytogenetic analysis and RT-PCR detection revealing a diagnosis of CML, for which hydroxyurea chemotherapy was initiated. Leukocyte count of the patient gradually returned to normal. After 24 days, the patient regained consciousness and on day 30, repeat CT scan showed no SDH recurrence. The patient recovered with no neurological deficits and achieved a good prognosis.

Splenic artery embolization changes the management of blunt splenic injury: an observational analysis of 680 patients graded by the revised 2018 AAST-OIS.

BACKGROUND: This study aimed to evaluate the management of blunt splenic injury (BSI) and highlight the role of splenic artery embolization (SAE). METHODS: We conducted a retrospective review of all patients with BSI over 15 years. Splenic injuries were graded by the 2018 revision of the American Association for the Surgery of Trauma-Organ Injury Scale (AAST-OIS). Our hospital provide 24/7 in-house surgeries and 24/7 in-house interventional radiology facility. Patients with BSI who arrived hypotensive and were refractory to resuscitation required surgery and patients with vascular injury on abdominal computed tomography were considered for SAE. RESULTS: In total, 680 patients with BSI, the number of patients who underwent nonoperative management with observation (NOM-obs), SAE, and surgery was 294, 234, and 152, respectively. The number of SAEs increased from 4 (8.3%) in 2001 to 23 (60.5%) in 2015 (p < 0.0001); conversely, the number of surgeries decreased from 21 (43.8%) in 2001 to 4 (10.5%) in 2015 (p = 0.001). The spleen-related mortality rate of NOM-obs, SAEs, and surgery was 0%, 0.4%, and 7.2%, respectively. In the SAE subgroup, according to the 2018 AAST-OIS, 234 patients were classified as grade II, n = 3; III, n = 21; IV, n = 111; and V, n = 99, respectively.; and compared with 1994 AST-OIS, 150 patients received a higher grade and the total number of grade IV and V injuries ranged from 96 (41.0%) to 210 (89.7%) (p < 0.0001). On angiography, 202 patients who demonstrated vascular injury and 187 achieved hemostasis after SAE with a 92.6% success rate. Six of the 15 patients failed to SAE preserved the spleen after second embolization with a 95.5% salvage rate. CONCLUSIONS: Our data confirm the superiority of the 2018 AAST-OIS and support the role of SAE in changing the trend of management of BSI.

A Novel Dual-Energy CT Method for Detection and Differentiation of Intracerebral Hemorrhage From Contrast Extravasation in Stroke Patients After Endovascular Thrombectomy : Feasibility and First Results.

PURPOSE: Dual-energy computed tomography (DECT) has been shown to be able to differentiate between intracranial hemorrhage (ICH) and extravasation of iodinated contrast media (contrast staining [CS]). TwinSpiral DECT is a recently introduced technique, which allows image acquisition at two different energy levels in two consecutive spiral scans. The aim of this study was to evaluate the feasibility and accuracy of TwinSpiral DECT to distinguish between ICH and CS after endovascular thrombectomy (EVT) in patients with acute ischemic stroke. METHODS: This retrospective single-center study conducted between November 2019 and July 2020 included non-contrast TwinSpiral DECT scans (tube voltages 80 and 150Sn kVp) of 39 ischemic stroke patients (18 females, 21 males, mean age 69 ± 11 years) within 48-72 h after endovascular thrombectomy. Parenchymal hyperdensity was assessed for the presence of ICH or/and CS by two board certified and fellowship-trained, blinded and independent neuroradiologists using standard mixed images and virtual non-contrast (VNC) images with corresponding iodine maps from TwinSpiral DECT. Follow-up examinations (FU; CT or MRI) were used as a standard of reference. Sensitivity, specificity, and accuracy for the detection of ICH as well as the inter-reader agreement were calculated. RESULTS: Parenchymal hyperdensities were detected in 17/39 (44%) patients. Using DECT, they were classified by both readers as ICH in 9 (53%), CS in 8 (47%), and mixture of both in 6 (35%) cases with excellent agreement (κ = 0.81, P < 0.0001). The sensitivity, specificity, and accuracy for the detection of ICH in DECT was 90% (95% confidence interval [CI]: 84-96%), 100% (95% CI 94-100%) and 95% (95% CI 89-100%), and in mixed images 90% (95% CI 84-96%), 86% (95% CI 80-92%) and 88% (95% CI 82-94%), respectively. Inter-reader agreement for detecting ICH on DECT compared to the mixed images was κ = 1.00 (P < 0.0001) vs. κ = 0.51 (P = 0.034). CONCLUSION: TwinSpiral DECT demonstrates high accuracy and excellent specificity for differentiating ICH from CS in patients after mechanical thrombectomy due to acute ischemic stroke, and improves inter-reader agreement for detecting ICH compared to the standard mixed images.

An audit of contrast extravasation in patients undergoing contrast enhanced CTs at radiology department in a tertiary care hospital in Pakistan.

OBJECTIVE: To audit the radiology department of a health facility, focusing on contrast extravasations management pre- and post-implementation of a standard protocol. METHODS: The audit was conducted at the Radiology Department of Shifa International Hospital, Islamabad, Pakistan and comprised reported computed tomography contrast extravasation incidents from January 2017 to December 2019 in the retrospective phase before the implementation of a standard protocol. Post-implementation, re-audit was done prospectively to assess compliance from January 2020 to May 2021. Overall score of >80% was chosen arbitrarily as a qualifying standard for adequate documentation. RESULTS: Of the 49 total cases, 26(53%) related to the first phase and 23(47%) to the second. In the first phase, 2(20%) of the 10 parameters cleared the cut-off mark; 'study performed' 25(96%) and 'limb assessment by technician' 26(100%). In the second phase, 2(20%) parameters failed to clear the cut-off mark; site of cannula/extravasation' 18(78.3%) and 'volume of contrast' 15(65%). CONCLUSIONS: Lack of early identification and appropriate management, especially in cases of large-volume extravasation, may result in significant morbidity.

Pediatric trauma and the role of the interventional radiologist.

PURPOSE: While interventional radiologists occupy a critical role in adult trauma management, the role of interventionalist in pediatric trauma continues to evolve. The indications for transarterial embolization (TAE) are significantly different in pediatric patients in whom non-operative management (NOM) has a much more prominent role than in adults. Contrast extravasation on imaging may not require acute surgical or interventional management as it would in an adult. There are also areas in which pediatric interventional radiology is increasingly useful such as pelvic TAE in failed management, or splenic embolization to treat bleeding without the loss of splenic function inherent to surgical splenectomy. The rapid evolution of techniques and devices in pediatric patients is also changing what interventions are possible in pediatric trauma management which necessitates frequent reassessment of the guidelines and interventional radiology's role in caring for these patients. CONCLUSION: This review seeks to consolidate the recent literature to describe the evolving role of the interventional radiologist in pediatric trauma management.

Pseudo Subarachnoid Hemorrhage Sign in Bacterial Meningitis in a Patient Presenting With Acute Ischemic Stroke: A Novel Radiological Clue to Rapid Diagnosis.

Pseudo subarachnoid hemorrhage (SAH) is an entity defined when characteristic computed tomography (CT) findings of SAH are seen without evidence of hemorrhage on MRI, autopsy, or cerebrospinal fluid analysis. This imaging phenomenon has been reported in association with multiple clinical settings including diffuse cerebral edema, hypoxic-ischemic injury, post percutaneous coronary intervention, and the focus of our report, acute bacterial meningitis. The mechanisms leading to this finding are poorly understood. Current hypotheses explaining this pattern vary widely depending on the associated pathology. In this report, we present a case of pseudo SAH associated with bacterial meningitis and a literature review on the causes, neuroimaging findings, and mechanisms associated with pseudo SAH. We discuss dual energy CT as a possible tool for differentiating pseudo SAH from true SAH. We analyze the timing of imaging studies and the role timing plays in the presentation of the pseudo SAH sign. We conclude that the extravasation of iodine contrast into the subarachnoid space can mimic SAH on CT. Ultimately, our case adds to the growing body of evidence that clinicians should be aware of acute bacterial meningitis as a potential mimic of SAH on CT.

Comparative Studies of Cerebral Reperfusion Injury in the Posterior and Anterior Circulations After Mechanical Thrombectomy.

Cerebral reperfusion injury is the major complication of mechanical thrombectomy (MT) for acute ischemic stroke (AIS). Contrast extravasation (CE) and intracranial hemorrhage (ICH) are the key radiographical features of cerebral reperfusion injury. The aim of this study was to investigate CE and ICH after MT in the anterior and posterior circulation, and their effect on functional outcome. This is a retrospective study of all consecutive patients who were treated with MT for AIS at University of California Irvine Medical Center between January 1, 2014, and December 31, 2017. Patient characteristics, clinical features, procedural variables, contrast extravasation, ICH, and outcomes after MT were analyzed. A total of 131 patients with anterior circulation (AC) stroke and 25 patients with posterior circulation (PC) stroke underwent MT during the study period. There was no statistically significant difference in admission NIHSS score, blood pressure, rate of receiving intravenous tPA, procedural variables, contrast extravasation, and symptomatic ICH between the 2 groups. Patients with PC stroke had a similar rate of favorable outcome (mRS 0-2) but significantly higher mortality (40.0% vs. 10.7%, p < 0.01) than patients with AC stroke. Multivariate regression analysis identified initial NIHSS score (OR 1.1, CI 1.0-1.2, p = 0.01), number of passes with stent retriever (OR 2.1, CI 1.3-3.6, p < 0.01), and PC stroke (OR 9.3, CI 2.5-35.1, p < 0.01) as independent risk factors for death. There was no significant difference in functional outcomes between patients with and without evidence of cerebral reperfusion injury after MT. We demonstrated that AC and PC stroke had similar rates of cerebral reperfusion injury and favorable outcome after MT. Cerebral reperfusion injury is not a significant independent risk factor for poor functional outcome.