Force and aspiration on catheters utilized in the ADAPT technique in acute ischemic stroke: A bench top analysis.

INTRODUCTION: Given the high morbidity and mortality of stroke, there remains a demand for techniques that provide rapid and safe intervention while improving time to recanalization. The direct aspiration first pass technique (ADAPT) uses force and aspiration for clot removal without the aid of separators or retrievers. In this study, we compare the force and aspiration qualities of commercially available catheters. METHODS: Four different catheters with varying inner diameters were set up in a bench top model to test catheter tip pressure and flow rate. Catheter tip pressure was measured by attaching the catheter to a vacuum pressure gauge and an aspiration pump. The flow rate was calculated by measuring the volume of room temperature water aspirated through each catheter over a given time. RESULTS: The Microvention Sofia catheter generated the greatest tip force (21.32 g), and the Stryker AXS Catalyst 6 catheter generated the smallest tip force (15.88 g). The Penumbra ACE 068 catheter and Medtronic ARC catheter measured 20.87 g and 16.78 g respectively. The ACE 068 had highest rate of aspiration at 289 mL/min, and the Catalyst 6 catheter had the lowest rate at 214. The Microvention Sofia catheter had the second highest rate while the ARC had the third highest rate, measuring 285 mL/min and 256 mL/min, respectively. CONCLUSIONS: When using the ADAPT technique, knowledge of the tip force and catheter flow rate of newer catheters with larger distal inner diameters may guide selection of aspiration catheters. While this study demonstrates differences in tip force and flow rate of different commercially available catheters, clinical translation will require further testing and evaluation.

Thromboelastography defines late hypercoagulability after TBI: a pilot study.

INTRODUCTION: Traumatic brain injury (TBI) is associated with a hypercoagulable state, the mechanism and duration of which remain unclear. We sought to determine whether thromboelastography (TEG) analysis could identify the hypercoagulable state after TBI, as defined by elevations in maximal amplitude (MA), thrombus generation (TG), G value (G), and alpha angle (αA). METHODS: Patients with moderate-severe TBI, defined primarily as a GCS <12, admitted between 1/2012 and 8/2013 were eligible for enrolment in this prospective cohort study. TEG profiles were obtained between 0-24 h (T1), 24-48 h (T2), 48-72 h (T3), 72-96 h (T4), and 96-120 h (T5) after admission. Early TEG was defined as 0-48 h, and late TEG was defined as >48 h. RESULTS: Twenty five patients (80 % men) and 7 age- and sex-matched control subjects were studied. Median age was 38 years (range 18-85). Early MA was [63.6 mm (60.5, 67.4)] versus late MA [69.9 mm (65.2,73.9); p = 0.02], early TG was [763.3 mm/min (712.8, 816.2)] versus late TG [835.9 mm/min (791.2,888.3); p = 0.02], and early G was [8.8 d/cm(2) (7.7,10.4)] versus late G [11.6 d/cm(2) (9.4,14.1); p = 0.02]. Study patients had higher MA (p = 0.02), TG (p = 0.03), and G (p = 0.02) values at T5 compared to controls. There was a linear increase per day of MA by 2.6 mm (p = 0.001), TG 31.9 mm/min (p ≤ 0.001), and G value by 1.3 d/cm(2) (p ≤ 0.001) when clustered by pairs in regression analysis. Lower MA values trended toward home discharge (p = 0.08). CONCLUSION: The data suggest a progressive and delayed hypercoagulable state observed days after initial TBI. The hypercoagulable state may reflect excess platelet activity.

Artificial Intelligence in Head and Neck Imaging.

Artificial intelligence (AI) can be applied to head and neck imaging to augment image quality and various clinical tasks including segmentation of tumor volumes, tumor characterization, tumor prognostication and treatment response, and prediction of metastatic lymph node disease. Head and neck oncology care is well positioned for the application of AI since treatment is guided by a wealth of information derived from CT, MRI, and PET imaging data. AI-based methods can integrate complex imaging, histologic, molecular, and clinical data to model tumor biology and behavior, and potentially identify associations, far beyond what conventional qualitative imaging can provide alone.

Portal Vein Thrombosis: Diagnosis and Endovascular Management.

BACKGROUND: Portal vein thrombosis (PVT) is a rare but severe entity that can cause clinically significant sequela such as worsening portal hypertension or mesenteric ischemia. Those cases refractory to medical management may be referred for endovascular intervention. Several technical considerations have been described in the literature, but a cohesive comparison of these multiple techniques is lacking. METHODS: The purpose of this article is to review the diagnosis and endovascular management of PVT, including areas in which further research is warranted. RESULTS: Cases of PVT can be readily diagnosed using ultrasound, computed tomography, or magnetic resonance imaging. Treatment often begins with systemic anticoagulation and endovascular interventions may be used in selected cases. Determining the optimal approach to accessing the portal venous system depends on the underlying disease and chronicity of the thrombus and the degree of occlusion. Once access to the portal venous system is established, catheter-directed therapy may be performed to achieve recanalization. CONCLUSION: Despite the heterogeneity in patient presentation, cases of PVT can be readily diagnosed across several imaging modalities. Strategizing interventional approaches involves evaluation of the underlying disease and the chronicity of the thrombus. KEY POINTS: · This review will enable interventionalists to establish a framework for treating portal vein thrombosis by identifying patient risk factors and thrombus characteristics that determine patient management.. · The unique risks and benefits for transhepatic, transsplenic, and transmesenteric approaches for establishing portal venous access will be discussed.. · Advantages and complications of thrombolysis, thrombectomy, and transjugular intrahepatic portosystemic shunt creation for treating portal vein thrombosis will be reviewed in detail based on our extensive institutional experience.. CITATION FORMAT: · Ju C, Li X, Gadani S et al. Portal Vein Thrombosis: Diagnosis and Endovascular Management. Fortschr Röntgenstr 2022; 194: 169 - 180.

Predictors of Occurrence and Risk of Hepatic Encephalopathy After TIPS Creation: A 15-Year Experience.

PURPOSE: To identify clinical variables, including use of newer Viatorr TIPS endoprosthesis with controlled expansion (VCX) that may affect the occurrence and risk of hepatic encephalopathy after transjugular intrahepatic portosystemic shunt (TIPS) creation. METHODS: A total of 376 patients who underwent TIPS creation at our institution between 2003 and 2018 were retrospectively identified. Of these patients, 71 received a Viatorr controlled expansion endoprosthesis and 305 received a Viatorr TIPS endoprosthesis (older version without controlled expansion). Multivariate regression analysis was used to identify factors predicting the occurrence of hepatic encephalopathy after TIPS creation; a Cox proportional hazard model was used to assess risk of HE through time to HE onset RESULTS: A total of 194 patients (52%) developed hepatic encephalopathy after TIPS creation, including 28 of 71 patients (39%) who received a VCX endoprosthesis. Older patient age and the use of Viatorr endoprosthesis without controlled expansion were significantly associated with the development of hepatic encephalopathy overall. Pre-TIPS pressure variables, patient age, plasma international normalized ratio, and model for end-stage liver disease score were risk factors for time to hepatic encephalopathy. CONCLUSION: Several variables are mild predictors of early hepatic encephalopathy development after TIPS creation, and the use of VCX endoprosthesis in TIPS creation is associated with a modest lower risk of hepatic encephalopathy. These preliminary findings should be considered in regard to patient selection, endoprosthesis selection, and post-transjugular intrahepatic portosystemic shunt creation monitoring for the development of hepatic encephalopathy.

Subarachnoid Hemorrhage Associated with Intratumoral Aneurysm Rupture within a Posterior Fossa Hemangioblastoma: The Importance of Continued Surveillance for Cerebral Vasospasm.

Cerebellar hemangioblastomas are rare tumors of the neuraxis. Only seven cases of hemangioblastoma associated with a cerebral aneurysm have been reported. We report a case of a patient who presented with acute onset headache as a result of subarachnoid hemorrhage (SAH) and hydrocephalus. Radiographic workup revealed a hemangioblastoma with an intratumoral aneurysm. Preoperative cerebral angiography was performed for both embolization as well as characterization of the aneurysm. The patient underwent a suboccipital craniotomy for tumor resection. The patient's postoperative course was unexpectedly complicated by delayed ischemic neurologic deficit secondary to flow-limiting left internal carotid artery vasospasm. We present a case report, review of the literature, and management considerations for patients who present with tumors and an associated ruptured aneurysm.

Thromboelastography Parameter Predicts Outcome After Subarachnoid Hemorrhage: An Exploratory Analysis.

OBJECTIVE: Hypercoagulability after subarachnoid hemorrhage (SAH) is well described and may be platelet mediated. Thromboelastography (TEG) provides a global assessment of coagulation. We sought to determine whether the maximum amplitude (MA) parameter of TEG, a measure of platelet strength and function, is associated with outcome after SAH. METHODS: One hundred ten TEG analyses were performed for patients with moderate-to-severe SAH and compared with 6 healthy age- and sex-matched controls. TEG indices included MA, G value (G), alpha angle, and thrombus generation and were correlated to functional outcomes and laboratory tests including complete blood count, erythrocyte sedimentation rate, high sensitivity C-reactive protein, fibrinogen, and d-dimer, obtained on post-bleed days (PBDs) 1, 3, 5, 7, and 10. RESULTS: MA was significantly elevated compared with controls on PBD 3 (70.0 mm ± 4.5 mm vs. 64.1 mm ± 6.5 mm; P = 0.02), PBD 5 (72.6 mm ± 5.3 mm vs. 64.1 mm ± 6.5 mm; P = 0.003), PBD 7 (73.0 mm ± 5.4 mm vs. 64.1 mm ± 6.5 mm; P = 0.003), and PBD 10 (73.4 mm ± 6.0 mm vs. 64.1 mm ± 6.5 mm; P = 0.005). G was significantly elevated compared with controls on PBD 3 (P = 0.03), PBD 5 (P = 0.01), PBD 7 (P = 0.01), and PBD 10 (P = 0.02). The only biomarker associated with poor outcome was CRP. Multivariate logistic regression demonstrated an association between elevated MA and outcome (odds ratio 39.1, P = 0.006) independent of CRP, age, Hunt Hess grade, and transfusion. CONCLUSIONS: TEG indices are associated with poor outcome after SAH and may identify a platelet-mediated hypercoagulable state. The association between MA and outcome was stronger than that between traditional biomarkers and was independent of age and Hunt Hess grade.