Modeling stroke in animals is essential for testing efficacy of new treatments; however, previous neuroprotective therapies, based on systemic delivery in rodents failed, exposing the need for model with improved clinical relevance. The purpose of this study was to develop endovascular approach for inducing ischemia in swine. To achieve that goal, we used intra-arterial administration of thrombin mixed with gadolinium and visualized the occlusion with real-time MRI. Placement of the microcatheter proximally to rete allowed trans-catheter perfusion of the ipsilateral hemisphere as visualized by contrast-enhanced perfusion MR scans. Dynamic T2*w MRI facilitated visualization of thrombin + Gd solution transiting through cerebral vasculature and persistent hyperintensities indicated occlusion. Area of trans-catheter perfusion dynamically quantified on representative slice before and after thrombin administration (22.20 ± 6.31 cm2 vs. 13.28 ± 4.71 cm2 respectively) indicated significantly reduced perfusion. ADC mapping showed evidence of ischemia as early as 27 min and follow-up T2w scans confirmed ischemic lesion (3.14 ± 1.41 cm2). Animals developed contralateral neurological deficits but were ambulatory. Our study has overcome long lasting challenge of inducing endovascular stroke model in pig. We were able to induce stroke using minimally invasive endovascular approach and observe in real-time formation of the thrombus, blockage of cerebral perfusion and eventually stroke lesion.
Background: Although pregnancy has been identified as one of the risk factors for venous disease, the mechanism of this interaction remains unclear. Possibly, pregnancy results in overstrain and vein dilatation, which exceed their durability and persist after pregnancy. The aim of this study was the assessment of the relationship between the number of pregnancies in women with venous disease and the selected parameters of their venous systems. Patients and methods: The retrospective assessment concerned 518 patients subjected to the diagnostics of the venous system in the lower limbs and the abdomen/pelvis using ultrasound scan and magnetic resonance or computed tomography. Results: We found that the occurrence of pelvic venous symptoms increases proportionally to the number of pregnancies and is correlated with ovarian and parauterine vein dilatation/incompetence (e.g., 13.5%of nulliparous women reported pelvic pain, and reflux in left ovarian veins was detected in 21.4% of the patients from that group, whereas in women after two pregnancies, pain and reflux concerned 22.8% and 90.6% of patients, respectively). In the nulliparous group, the development of venous disease resulted from the presence of anatomic abnormalities in abdominal/pelvic veins. Conclusions: Our report proved that the number of pregnancies is correlated with the incidence of pelvic vein insufficiency. Although not specifically addressed in this study, some correlation was found with saphenous disease as well. However, further studies are necessary to provide more evidence about the role of pelvic vein insufficiency in chronic venous disease of the lower limbs.
Patients with malignant brain tumors have a poor prognosis. The blood–brain barrier (BBB) is considered a primary obstacle in therapeutic drug delivery to the brain. Intra-arterial (IA) delivery of therapeutic agents following osmotic BBB opening has been attempted for years, but high variability has limited its widespread implementation. It has recently been shown in animal studies that MRI is superior to X-ray for guiding IA infusions, as it allows direct visualization of the brain parenchyma supplied by the catheter and facilitates predictable drug targeting. Moreover, PET imaging has shown that IA rather than intravenous delivery of bevacizumab results in accumulation in the brain, providing a strong rationale for using the IA route. We present a patient with recurrent butterfly glioblastoma enrolled in a first-in-man MRI-guided neurointervention for targeted IA drug delivery.
Ovarian veins system insufficiency is one of the most common reasons for pelvic venous insufficiency (PVI). PVI is a hemodynamic phenomenon responsible for the occurrence of venous insufficiency of the lower extremities and recurrent varicose veins in nulliparous and parous women, as well as for a set of symptoms described as pelvic congestion syndrome (PCS). In the years 2017–2019, 535 patients admitted to our center with symptoms of venous insufficiency of the lower extremities, underwent complete ultrasound diagnostics (color-duplex ultrasound) of the venous system of the abdomen, pelvis and lower limbs, as well as extended imaging diagnostics using computed tomography (CT) or magnetic resonance (MR) venography. On the basis of the obtained results, the authors proposed a 4-grade hemodynamic and radiological classification (grades I-IV) defining the stratification of ovarian veins insufficiency. Using the above mentioned classification approx. 32% patients were identified as Grade I and I/II, approximately 35% revealed morphological and hemodynamic changes corresponding to Grade II and II/III, approximately 25% were classified as Grade III, whereas the remaining 8% were assessed as Grade IV. The described classification allows for the grading of ovarian veins insufficiency based on transparent radiological criteria, making it easy to use in everyday clinical practice. According to the authors, the proposed classification could facilitate communication between diagnostic physicians, specialists dealing with the treatment of venous insufficiency and gynecologists, who admit patients with symptoms suggesting venous insufficiency of the pelvis.
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