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Cerebral venous thrombosis (CVT) is a rare cerebral vascular disease, the presentation of which is highly variable clinically and radiologically. A recent study demonstrated that isolated subarachnoid hemorrhage (iSAH) in CVT is not as rare as thought previously and may have a good prognostic significance. Hemorrhagic venous infarction, however, is an indicator of an unfavorable outcome. We therefore hypothesized that patients who initially suffered iSAH would have a better clinical outcome than those who suffered hemorrhagic cerebral infarction.

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can assess tumour vascularity, which depends on the process of angiogenesis and affects tumour response to treatment. Our study explored the associations between DCE-MRI parameters and the expression of plasma angiogenic factors in human papilloma virus (HPV)-negative oropharyngeal cancer, as well as their predictive value for response to concurrent chemoradiotherapy (cCRT). Twenty-five patients with locally advanced HPV-negative oropharyngeal carcinoma were prospectively enrolled in the study. DCE-MRI and blood plasma sampling were conducted before cCRT, after receiving a radiation dose of 20 Gy, and after the completion of cCRT. Perfusion parameters ktrans, kep, Ve, initial area under the curve (iAUC) and plasma expression levels of angiogenic factors (vascular endothelial growth factor [VEGF], connective tissue growth factor [CTGF], platelet-derived growth factor [PDGF]-AB, angiogenin [ANG], endostatin [END] and thrombospondin-1 [THBS1]) were measured at each time-point. Patients were stratified into responders and non-responders based on clinical evaluation. Differences and correlations between measures were used to generate prognostic models for response prediction. Higher perfusion parameter ktrans and higher plasma VEGF levels successfully discriminated responders from non-responders across all measured time-points, whereas higher iAUC and higher plasma PDGF-AB levels were also discriminative at selected time points. Using early intra-treatment measurements of ktrans and VEGF, a predictive model was created with cut-off values of 0.259 min−1 for ktrans and 62.5 pg/mL for plasma VEGF. Early intra-treatment DCE-MRI parameter ktrans and plasma VEGF levels may be valuable early predictors of response to cCRT in HPV-negative oropharyngeal cancer. [ABSTRACT FROM AUTHOR]

Intravenous thrombolysis (IVT) is the method of choice in reperfusion treatment of patients with signs and symptoms of acute ischemic stroke (AIS) lasting less than 4.5 hours. Hemorrhagic transformation (HT) of acute ischemic stroke is a serious complication of IVT and occurs in 4.5–68.0% of clinical cases. The aim of our study was to determine the infarct core CT perfusion parameter (CTPP) most predictive of HT.

Inflammatory events in brain parenchyma and glial tissue are involved in epileptogenesis. Blood concentration of cytokines is shown to be elevated after tonic-clonic seizures. As a result of inflammation, blood-brain barrier leakage occurs. This can be documented by imaging techniques, such is dynamic susceptibility contrast enhanced (DSC) MRI perfusion. Our aim was to check for postictal brain inflammation by studying DSC MRI perfusion and plasma level of cytokines. We looked for correlations between number and type of introducing seizures, postictal plasma level of cytokines and parameters of DSC MRI perfusion. Furthermore, we looked for correlation of those parameters and course of the disease over one year follow up.

The aim of the study was to investigate the sensitivity and specificity of non-contrast computed tomography (NCCT) in the diagnosis of cerebral venous sinus thrombosis (CVST).

Background. Endovascular embolization is a treatment of choice for the management of unruptured intracranial aneurysms, but sometimes is complicated with perianeurysmal oedema. The aim of our study was to establish incidence and outcomes of perianeurysmal oedema after endovascular coiling of unruptured intracranial aneurysms, and to reveal possible risk factors for development of this potentially serious complication.

Background. The blood-brain barrier represents the selective diffusion barrier at the level of the cerebral microvascular endothelium. Other functions of blood-brain barrier include transport, signaling and osmoregulation. Endothelial cells interact with surrounding astrocytes, pericytes and neurons. These interactions are crucial to the development, structural integrity and function of the cerebral microvascular endothelium. Dysfunctional blood-brain barrier has been associated with pathologies such as acute stroke, tumors, inflammatory and neurodegenerative diseases.

Background. Clinical features indicating an ischemic infarction in the territory of posterior cerebral circulation require a comprehensive radiologic examination, which is best achieved by a multi-modality imaging approach (computed tomography [CT], CT-perfusion, computed tomography angiography [CTA], magnetic resonance imaging [MRI] and diffusion weighted imaging [DWI]). The diagnosis of an acute ischemic infarction, where the damage of brain tissue may still be reversible, enables selection of appropriate treatment and contributes to a more favourable outcome. For these reasons it is essential to recognize common neurovascular variants in the territory of the posterior cerebral circulation, one of which is the artery of Percheron.

Background: Intravenous thrombolysis (IVT) is the method of choice in reperfusion treatment of patients with signs and symptoms of acute ischemic stroke (AIS) lasting less than 4.5 hours. Hemorrhagic transformation (HT) of acute ischemic stroke is a serious complication of IVT and occurs in 4.5–68.0% of clinical cases. The aim of our study was to determine the infarct core CT perfusion parameter (CTPP) most predictive of HT. Patients and methods: Seventy-five patients with AIS who had undergone CT perfusion (CTP) imaging and were treated with IVT were enrolled in this retrospective study. Patients with and without HT after IVT were defined as cases and controls, respectively. Controls were found by matching for time from AIS symptom onset to IVT ± 0.5 h. The following CTPPs were measured: cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), relative CBF (rCBF) and relative CBV (rCBV). Receiver operating characteristic analysis curves of significant CTPPs determined cut-off values that best predict HT. Results: There was a significant difference between cases and controls for CBF (p = 0.004), CBV (p = 0.009), rCBF (p < 0.001) and rCBV (p = 0.001). Receiver operating characteristic analysis revealed that rCBF < 4.5% of the contralateral mean (area under the curve = 0.736) allowed prediction of HT with a sensitivity of 71.0% and specificity of 52.5%. Conclusions: CTP imaging has a considerable role in HT prediction, assisting in selection of patients that are likely to benefit from IVT. rCBF proved to have the highest HT predictive value. [ABSTRACT FROM AUTHOR]

Purpose: Perfusion computed tomography imaging (PCT) is a robust, reproducible, widely accessible non-invasive method. The objective of our study was to assess whether prospectively collected pretreatment PCT parameters and volumetric measurements of locoregionally advanced squamous cell carcinoma (SCCA) of the oral cavity, oropharynx and hypopharynx could predict the response to concomitant chemoradiotherapy with cisplatin Methods: Pretreatment contrast enhanced PCT was performed in 30 patients. Radiologic response criteria (RECIST) were used to evaluate tumor response. The correlation and predictive value of baseline PCT parameters and tumor volume were examined by using the Student's t-test, Pearson's correlation coefficient and receiver operating characteristic (ROC) curves., Results: Baseline tumor volume, blood volume (BV) and blood flow (BF) were significantly higher in responders than in non-responders. Permeability surface (PS) did not show any significant difference between the two groups. Pretreatment tumor volume correlated with baseline BV (r=-0.4; p=0.01). Pretreatment tumor volume had 100% sensitivity and specificity (p=0.0001) and BV and BF also showed satisfactory sensitivity and specificity (100% and 65%, p=0.0002; 78% and 80.2%, p=0.01, respectively) for prediction of tumor response to concomitant chemoradiotherapy with cisplatin., Conclusion: Baseline BV, BF and tumor volume values were significantly different between responders and non-responders and could predict response to concomitant chemoradiotherapy with cisplatin in locoregionally advanced SCCA.

Background: Bisphosphonates are drugs used in the treatment of lytic bone metastases, multiple myeloma, hypercalcemia of malignant origin, osteoporosis, and diseases such as Paget's disease. Recently osteonecrosis of the jaw has been associated with the use of bisphosphonates. This study describes the imaging findings of bisphosphonate-associated osteonecrosis of the jaws., Patients and Methods: Eleven patients, receiving bisphosphonate medication for approximately 28 months, with pain on affected side, nonhealing extraction sockets, purulent discharge and swelling in soft tissue were examined. Imaging consisted of non-contrast enhanced CT and contrast enhanced MRI. All patients underwent surgery of affected bone and histology confirmed osteonecrosis., Results: CT scan showed osteolytic and sclerotic lesions with cortical bone destruction in all patients. The osteonecrosis was identified as delimited focal lesions with reduction of the signal on T1- weighted imaging and T2- weighted imaging. All the patients had soft-tissue involvement with enhancement in orbicular, buccinator muscle of the mouth or masticator space and adenopathy in submandibular and jugular digastric chain., Conclusions: Bisphosphonate related osteonecrosis of the jaw presents a variety of imaging findings that help to determine the extent of the disease and track the progression, however they are not specific for this disease.