[Preparation and investigation of MRI-traceable Eudragit-E liquid embolic agent].

OBJECTIVE: To develop and investigate the properties of MRI-traceable Eudragit-E liquid embolic agent (MR-E). METHODS: Polyethylene glycol-modified superparamagnetic iron oxides (PEG-SPIO) was synthesized by chemical co-precipitation method. MR-E was prepared by mixing PEG-SPIO and Eudragit-E liquid embolic agent homogeneously. An in vitro MR phantom study was carried out to measure MR traceability of MR-E and to determine the concentration of PEG-SPIO for further studies. The microcatheter deliverability and sol-gel transition process of MR-E were investigated. MR-E was injected into the kidney of a Japanese white big ear rabbit via an angiographic microcatheter, and detected by MRI. RESULTS: A PEG-SPIO concentration of 2 g/L was considered to be suitable for further studies. MR-E was injected through the microcatheter without any difficulty. MR-E instantly solidified on release into saline. Then 0.2 mL of MR-E effectively embolized distal renal arteries, and MR-E could be detected by MRI in the embolized kidney. CONCLUSION: MR-E seems to be a promising MRI-traceable liquid embolic agent.

[Preparation and property study of doxorubicin loaded microspheres].

OBJECTIVE: To prepare doxorubicin-loaded polyvinylalcohol-acrylic acid (PVA-AA) microspheres and evaluate properties of this chemoembolic agent. METHODS: PVA-AA microspheres were synthesized by inverse suspension polymerization method and then verified by infrared spectroscopy. drug loading (DL) and entrapment efficiency (EE%) were measured after doxorubicinwas loaded on PVA-AA microspheres. Their morphology and elasticity were investigated by optical microscope, environmental scanning electron microscope and texture analyzer, respectively. T-cell apparatus was used to evaluate the in vitro release behavior of doxorubicin-loaded microspheres.The external carotid of the rabbit was chosen as an embolization site to evaluate the in vivo embolic property of the microspheres. RESULTS: PVA-AA microspheres, which were transparent spheres,turned into red spheres after doxorubicin loading. DL of the microspheres was (20.56 ± 0.69)g/L and (23.25 ± 0.27) g/L,and EE% was 82.22% ± 2.76% and 93.00% ± 1.06% within 20 min and 6 h, respectively. The in vitro release results showed a significantly delayed release of the drug for 10.32% ± 0.47% after 24 h. The Young's modulus was (178.30 ± 12.33) kPa and (213.29 ± 15.61) kPa for blank microspheres and doxorubicin-loaded microspheres, respectively. Both blank microspheres and doxorubicin-loaded microspheres exhibited good elasticity. In vivo embolization showed that 0.3 mL of microspheres could produce distal embolic efficiency. CONCLUSION: The doxorubicin-loaded microspheres are expected to be a promising new chemoembolic agent.

Contrast-enhanced ultrasound evaluation of renal perfusion before angioplasty and its predictive value for hypertension.

BACKGROUND: Atherosclerotic renal artery stenosis (ARAS) is a common disease in the elderly population. OBJECTIVE: The aim was to develop a contrast-enhanced ultrasound (CEUS)-based model for predicting post-angioplasty improvement in hypertension in patients with severe ARAS. METHODS: Thirty-five patients with severe ARAS (⩾ 70%) were included in this study, and 42 renal arteries received percutaneous transluminal renal arterial stenting. An optimal integral formula was developed from pre-interventional color-coded duplex sonography (CCDS) and CEUS parameters using least absolute shrinkage and selection operator (LASSO) regression and receiver operating characteristic (ROC) curve analysis. A model for predicting short-term hypertension improvement was established using the integral formula and clinical risk factors. Bootstrapping was used for internal validation. RESULTS: Two integral formulas, LASSO.CCDS and LASSO.CEUS, were established. ROC curves of the two integral formulas showed that LASSO.CEUS was the better formula for predicting hypertension improvement (AUC 0.816, specificity 78.6%). Univariate and multivariate regression analyses showed that duration of hypertension (OR 0.841, P= 0.027), diabetes (OR = 0.019, P= 0.010), and LASSO.CEUS (OR 7.641, P= 0.052) were predictors of short-term hypertension improvement after interventional therapy. Using LASSO.CEUS combined with clinical risk factors, the following prediction model was established: logit (short-term improvement in hypertension) = 1.879-0.173 × hypertension duration - 3.961 × diabetes + 2.034 × LASSO.CEUS (AUC 0.939). CONCLUSIONS: The model established using CEUS parameters and clinical risk factors could predict hypertension improvement after interventional therapy, but further research and verification are needed.

Arterial chemotherapy for hepatocellular carcinoma in China: consensus recommendations.

Hepatocellular carcinoma (HCC) is one of the most common malignancies and the third leading cause of cancer-related deaths globally. Hepatic arterial infusion chemotherapy (HAIC) treatment is widely accepted as one of the alternative therapeutic modalities for HCC owing to its local control effect and low systemic toxicity. Nevertheless, although accumulating high-quality evidence has displayed the superior survival advantages of HAIC of oxaliplatin, fluorouracil, and leucovorin (HAIC-FOLFOX) compared with standard first-line treatment in different scenarios, the lack of standardization for HAIC procedure and remained controversy limited the proper and safe performance of HAIC treatment in HCC. Therefore, an expert consensus conference was held on March 2023 in Guangzhou, China to review current practices regarding HAIC treatment in patients with HCC and develop widely accepted statements and recommendations. In this article, the latest evidence of HAIC was systematically summarized and the final 22 expert recommendations were proposed, which incorporate the assessment of candidates for HAIC treatment, procedural technique details, therapeutic outcomes, the HAIC-related complications and corresponding treatments, and therapeutic scheme management.

[Electroacupuncture improves long-term survival of myocardial infarction mice by promoting myocardial angiogenesis and inhibiting ventricular remodeling].

OBJECTIVE: To investigate the mechanism of electroacupuncture (EA) in improving the long-term survival rate of mice after myocardial infarction by promoting angiogenesis and inhibiting ventricular remodeling. METHODS: A total of 102 male C57BL/6 mice were randomly divided into sham operation, model and EA groups (n=34 /group). The myocardial infarction model was established by permanent ligation of the anterior descending branch of the left coronary artery. Beginning from the 3rd day after ligation, EA (2 Hz/20 Hz) was applied to bilateral "Neiguan" (PC6) and "Ximen" (PC4) for 30 min, once a day for 28 days. The survival rate in 140 d was recorded and the left ventricular ejection fraction (EF) calculated by using echocardiography after the treatment. The left cardiac ventricular tissue was cut into sections to be stained with Masson's trichrome, wheat germ agglutinin (WGA) or α-smooth muscle actin (α-SMA) immunohistochemistry method, followed by measuring the collagen area in the marginal region of myocardial infarction and calculating the collagen volume fraction (for assessing the severity of myocardial fibrosis), measuring the sectional area of cardiomyocytes (for assessing the degree of myocardial hypertrophy), and ob-serving the newborn blood vessels and calculating the ratio of neovascularization area (for assessing the state of angiogenesis). The expression of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor (HIF)-1α protein in the boundary area of myocardial infarction were detected by Western blot. RESULTS: After modeling, the survival rate, EF, and the thickness of the left cardiac ventricle were significantly decreased (P<0.01), whereas the percentage of collagen deposition area, sectional area of cardiomyocyte, percentage of angiogenesis area, and the expression levels of VEGF and HIF-1α proteins were significantly increased (P<0.01) in the model group relevant to the sham operation group. Compared with the model group, the survival rate, EF, the thickness of the left cardiac ventricle, the percentage of angiogenesis area, and the expression levels of VEGF and HIF-1α proteins were significantly increased (P<0.05, P<0.01), while the percentage of collagen deposition area and the sectional area of the cardiomyocyte were considerably decreased in the EA group (P<0.01, P<0.05). CONCLUSION: EA of PC6 and PC4 can significantly improve the cardiac function and long-term survival rate in mice with myocardial infarction, which may be related to its functions in up-regulating the expression of HIF-1α and VEGF to promote angiogenesis and in inhibiting ventricular remodeling.

[Pharmaceutical therapy for the severe hemodynamic depression with carotid artery stenting].

OBJECTIVE: To evaluate the efficacy of pharmaceutical therapy for the severe hemodynamic depression with carotid artery stenting(CAS). METHODS: Clinical data were retrospectively analyzed on CAS over the last 5 years. Severe hemodynamic depression was defined as periprocedural hypotension (blood pressure <90/60 mmHg) or bradycardia (heart rate <50 beats/min) persisting for at least 1 hour. 13 patients were included in the research. RESULTS: Dopamine was pumped intravenously in all the 13 patients .The dose was from 2 microg/min/kg to 10 microg/min/kg, the duration was from 4 to 48 hours. Dobutamine was used in 2 patients and dose from 5 microg/min/kg to 7 microg/min/kg, duration was from 24 to 36 hours. None of the patients developed any permanent neurological complications. One acute coronary syndrome occured during the postprocedure period. CONCLUSION: Severe hemodynamic depression can be controlled with vasopressors (dopamine or dobutamine) and the associated complications can be prevented.

[Cesarean scar pregnancy analysis of 42 cases].

OBJECTIVE: To discuss the diagnosis and treatment strategy of cesarean scar pregnancy (CSP). METHODS: Forty-two cases of CSP admitted to Peking University First Hospital from Jan. 2003 to Dec. 2008 were analyzed retrospectively, and the clinical characteristics, pelvic Doppler ultrasonography report, management including methotrexate (MTX) therapy, bilateral uterine artery embolism (UAE), curettage and hysterectomy of these 42 women were reviewed. The percentage of human chorionic gonadochopin (hCG) reduction, menstrual period after the treatment of her CSP and recurrent pregnant outcome were also followed. RESULTS: Among the 42 CSP women, 24 (57%) presented with vaginal bleeding, 3 (7%) with lower abdominal pain. The interval between CSP and the last cesarean scar (CS) was 0.5 - 18.0 years and the average duration of gestation was (60 +/- 18) days. Fourteen cases (33%) were finally diagnosed as CSP in our hospital followed by failure of abortion due to misdiagnosed as early uterine pregnancy in other hospitals; one (2%) was finally diagnosed after hysterectomy due to excessive bleeding during curettage because of suspected hydatidiform mole under color sonography; one was diagnosed by MRI after color sonography; the rest 25 women (60%) were all confirmed by color sonography before management. Treatment of these cases included curettage after UAE (17 cases), curettage after UAE and MTX (13 cases), curettage after MTX only (4 cases), MTX only (4 cases) and others (4 cases). No significant difference was found in the average duration of pregnancy, average reduction of serum level of hCG and the operation time for curettage between the first two management group (P > 0.05). All of the 42 cases fully recovered before discharge and the recovery time of menses was averagely (32 +/- 10) days (10 - 60 days) after curettage and 5 reported reduced menstrual blood volume. Three out of the 42 women were pregnant again during follow-up and 1 delivered by CS at 39 weeks of gestation one year after without any complications or CSP. CONCLUSIONS: CSP is not common and can be easily misdiagnosed and color ultrasound scan is important in its early diagnosis. UAE combined with MTX followed by curettage is an effective treatment of CSP.

MRI Detectable Polymer Microspheres Embedded With Magnetic Ferrite Nanoclusters For Embolization: In Vitro And In Vivo Evaluation.

OBJECTIVE: The objective of this study was to develop magnetic embolic microspheres that could be visualized by clinical magnetic resonance imaging (MRI) scanners aiming to improve the efficiency and safety of embolotherapy. METHODS AND DISCUSSION: Magnetic ferrite nanoclusters (FNs) were synthesized with microwave-assisted solvothermal method, and their morphology, particle size, crystalline structure, magnetic properties as well as T2 relaxivity were characterized to confirm the feasibility of FNs as an MRI probe. Magnetic polymer microspheres (FNMs) were then produced by inverse suspension polymerization with FNs embedded inside. The physicochemical and mechanical properties (including morphology, particle size, infrared spectra, elasticity, etc.) of FNMs were investigated, and the magnetic properties and MRI detectable properties of FNMs were also assayed by vibrating sample magnetometer and MRI scanners. Favorable biocompatibility and long-term MRI detectability of FNMs were then studied in mice by subcutaneous injection. FNMs were further used to embolize rabbits' kidneys to evaluate the embolic property and detectability by MRI. CONCLUSION: FNMs could serve as a promising MRI-visualized embolic material for embolotherapy in the future.

Poly(acrylic acid) microspheres loaded with superparamagnetic iron oxide nanoparticles for transcatheter arterial embolization and MRI detectability: In vitro and in vivo evaluation.

To develop embolic microspheres with MRI detectability, superparamagnetic iron oxide nanoparticles (SPIONs) were synthesized and mixed with monomer of acrylic acid to prepare SPIONs-loaded polymerized microspheres (SPMs) by inverse suspension polymerization method. The SPMs were evaluated for the ability of embolization by investigating the morphology, particle size, elasticity and renal arterial embolization to rabbits. Meanwhile, the loading of SPIONs was verified by optical microscope, transmission electron microscope, Fourier transform infrared spectrum, vibrating sample magnetometer, X-ray diffraction and X-ray photoelectron spectroscopy, and the content of SPIONs in SPMs was measured quantitatively. Furthermore, the MRI detectability of SPMs was testified in gel phantom, mice and rabbits respectively by a clinical 3.0T MRI scanner. The results revealed the SPMs were potential MRI detectable embolic microspheres for improving the effectiveness and safety of embolotherapy in the future.

[Pharmacokinetics of doxorubicin alginate microspheres and evaluation of its hepatic arterial embolization in vivo].

AIM: To investigate the pharmacokinetics of doxorubicin alginate microspheres (DOX-AM) in vivo after hepatic arterial embolization. METHODS: China miniature pigs were chosen as the experimental animals. Transcatheter hepatic arterial chemoembolization (TACE) with DOX-AM (experimental group), lipiodol and DOX (DOX-lipiodol, control group 1), and infusion with DOX (control group 2) were performed after angiography and superselection of an intrahepatic branch of hepatic artery. After chemoembolization or infusion, the blood was collected at different time intervals. Drug concentration in plasma was measured by HLPC and the parameters of pharmacokinetics were calculated. RESULTS: The values of T1/2, AUC, Cmax, and MRT of the DOX-AM were significantly different from those of control group 1 and control group 2. After embolization, the DOX-AM embolized in the vessel and still retained there at 8 weeks. The digital subtraction arteriography (DSA) and computerized tomography (CT) showed the reliable embolization results. The histological examination indicated that the liver damnifications were changed transitorily in all groups (P < 0.05) and were recovered within two weeks. The liver damnifications increased in following order: DOX < DOX-AM < DOX-lipiodol. CONCLUSION: DOX-AM showed definite property of delayed release of drug in liver, and increased the retention time and concentration of DOX after embolization in vivo.

[In vivo fluorescent microscopy of the liver microcirculation after embolization with a newly developed trans-proper hepatic arterial infusion animal model].

OBJECTIVE: To evaluate the value of the in vivo fluorescent microscopy in studying the changes of liver microcirculation after embolization with a newly developed animal model for tans-proper hepatic arterial infusion, and to summarize the method of making this animal model. METHODS: Ten Sprague-Dawley rats were used in this study. After a midline abdominal incision, microcatheter was placed into the gastroduodenal artery (GDA). The tip of the catheter was placed facing the orifice of proper hepatic artery. After infusions of 0.02%, 0.1%, 0.5%, 1% fluorescent sodium, fluorescent microscopy was used to evaluate the liver microcirculation. The image quality was then accessed. Embolization was obtained by injections of Lipiodol and Degradable Starch Microspheres (DSM) from the microcatheter. Corresponding changes of the liver microcirculation was evaluated by fluorescent microscopy. RESULTS: From the 10 rats, 8 animal models were successfully established. The microcirculation of the liver could be clearly visualized by the fluorescent microscopy. The optimal concentration of fluorescent sodium was 0.1%. The direct and indirect phenomena caused by embolic material could be evaluated by fluorescent microscopy. CONCLUSION: Fluorescent microscopy with the corresponding Trans-hepatic arterial infusion animal model is a valuable method to evaluate the microcirculation of the liver and can be used for the evaluation of changes of liver microcirculation caused by embolization material.

Preparation and evaluation of biocompatible long-term radiopaque microspheres based on polyvinyl alcohol and lipiodol for embolization.

The aim of this work was to develop long-term radiopaque microspheres (LRMs) by entrapping lipiodol in biocompatible polyvinyl alcohol with multiple emulsions chemical crosslinking method. The high content of lipiodol (0.366 g/mL) was hardly released from LRMs in vitro and the radiopacity could maintain at least 3 months after subcutaneous injection in mice without weakening. A series of tests was performed to evaluate the feasibility of LRMs for embolization. LRMs were proved to be smooth, spherical, and well dispersed with diameter range of 100-1200 µm. Young's modulus of LRMs was 55.39 ± 9.10 kPa and LRMs could be easily delivered through catheter without aggregating or clogging. No toxicity of LRMs was found to mouse L929 fibroblasts cells and only moderate inflammatory in surrounding tissue of mice was found after subcutaneous injection of LRMs. After LRMs were embolized in renal artery of a rabbit, the distribution and radiopacity of LRMs in vivo were easily detectable by X-ray fluoroscopy and computed tomography (CT) imaging, respectively. More accurate distribution of LRMs in embolized kidney and vessels could be detected by high-revolution visualization of micro-CT ex vivo. In conclusion, the LRMs were proved to be biocompatible and provide long-term radiopacity with good physical and mechanical properties for embolization.

Development and evaluation of liquid embolic agents based on liquid crystalline material of glyceryl monooleate.

New type of liquid embolic agents based on a liquid crystalline material of glyceryl monooleate (GMO) was developed and evaluated in this study. Ternary phase diagram of GMO, water and ethanol was constructed and three isotropic liquids (ILs, GMO:ethanol:water=49:21:30, 60:20:20 and 72:18:10 (w/w/w)) were selected as potential liquid embolic agents, which could spontaneously form viscous gel cast when contacting with water or physiological fluid. The ILs exhibited excellent microcatheter deliverability due to low viscosity, and were proved to successfully block the saline flow when performed in a device to simulate embolization in vitro. The ILs also showed good cytocompatibility on L929 mouse fibroblast cell line. The embolization of ILs to rabbit kidneys was performed successfully under monitoring of digital subtraction angiography (DSA), and embolic degree was affected by the initial formulation composition and used volume. At 5th week after embolization, DSA and computed tomography (CT) confirmed the renal arteries embolized with IL did not recanalize in follow-up period, and an obvious atrophy of the embolized kidney was observed. Therefore, the GMO-based liquid embolic agents showed feasible and effective to embolize, and potential use in clinical interventional embolization therapy.

Changes in immunological function after treatment with transarterial chemoembolization plus radiofrequency ablation in hepatocellular carcinoma patients.

BACKGROUND: Different strategies for hepatocellular carcinoma (HCC) may have distinct effects on the immune system. The aim of this research was to investigate changes in the immunological function after transcatheter arterial chemoembolization (TACE) plus radiofrequency ablation (RFA) in HCC patients. METHODS: A total of 51 consecutive HCC treatment-naïe patients was enrolled in this study and 20 healthy subjects served as controls. The therapeutic strategy was selected according to the tumor stage and general conditions. TACE was performed in 25 cases, TACE plus RFA in 17 and RFA in nine. All the patients underwent routine examinations and peripheral blood was harvested for the detection of lymphocyte subset by flow cytometry 1 day before, and 2 and 4 weeks after the treatment. The serum levels of alpha-fetoprotein (AFP), ALT and AST were also measured before and 4 weeks after treatment for the evaluation of therapeutic efficacy and liver function impairment. RESULTS: When compared with healthy controls, the CD4/CD8 ratio and the number of B cells and natural killer (NK) cells were significantly decreased in HCC patients before treatment (P < 0.05). When compared with before treatment, the CD4+ cells and CD4/CD8 ratio decreased but CD8+ cells increased in the TACE group (P < 0.05); the CD4/CD8 ratio and NK cells decreased but CD8+ cells increased in the TACE-RFA group (P < 0.05); the CD3+ cells, CD4+ cells, CD4/CD8 ratio and NK cells increased in the RFA group (P < 0.05). Significant differences in the CD3+ cells, CD8+ cells, CD4/CD8 ratio and NK cells were observed among groups (P < 0.05). Moreover, the AFP level decreased and transaminase level increased in all groups (P < 0.05). Differences of pre and post treatment between groups were statistically significant (P = 0.016, 0.025, 0.018 respectively). CONCLUSIONS: Immunity was compromised in HCC patients; TACE and TACE plus RFA lowered immunologic function to a certain extent. RFA improved it accompanied by a protective effect on liver function.

Rare anomalous origin of superior left pulmonary artery from left subclavian vein.

We report for the first time an extremely rare anomalous origin of the superior left pulmonary artery in a 60 year-old man. Although it was occult in clinical indications, such a malformation still ought to be considered, especially during endovascular procedures.

Research of novel biocompatible radiopaque microcapsules for arterial embolization.

Embolic agents, such as microparticles, microspheres or beads used in current embolotherapy are mostly radiolucent, which means the agents are invisible under X-ray imaging during and after the process of embolization, and the fate of these particles cannot be precisely assessed. In this research, a radiopaque embolic agent was developed by encapsulating lipiodol in polyvinyl alcohol. The lipiodol-containing polyvinyl alcohol microcapsules (LPMs) were characterized and evaluated for their morphology, size distribution, lipiodol content, lipiodol release, elasticity, and deliverability through catheter. The radiopacity of LPMs in vials and in living mice was both detected by an X-ray imaging system. The biocompatibility of LPMs was investigated with L929 cells and in mice after subcutaneous injection. Embolization of LPMs to a rabbit kidney was performed under digital subtraction angiography (DSA) and the radiopacity of LPMs was verified by computed tomography (CT).

High-flow priapism: superselective cavernous artery embolization with microcoils.

OBJECTIVES: To determine the effectiveness of superselective cavernous artery embolization. METHODS: Eight patients with high-flow priapism were included in this study. All were treated by superselective cavernous artery embolization with microcoils and gelatin sponges. The follow-up examinations consisted of color duplex ultrasonography. The International Index of Erectile Function 5-item questionnaire was used to investigate the patients' erectile function before the onset of priapism, at embolization, and 6 months after embolization. RESULTS: A unilateral cavernous fistula was found in 7 patients and bilateral fistulas in 1. Of the 8 patients, 2 (1 with unilateral and 1 with bilateral fistulas) initially underwent embolization with a gelatin sponge but presented with recurrence of tumescence 1 week after treatment and required a repeat embolization procedure with microcoils. The other 6 patients (75%) were successfully detumescent after embolization with microcoils. The 6 patients (75%) who underwent embolization with microcoils alone had normal erectile function with a mean International Index of Erectile Function score of 22.20 at 6 months after embolization. The 2 patients (25%) who had required repeat embolization had erectile dysfunction, with a mean International Index of Erectile Function score of 13.00. CONCLUSIONS: Superselective cavernous artery embolization with microcoils is a safe and effective treatment of high-flow priapism. The use of microcoils resulted in greater embolization success and preservation of erectile function, especially in the treatment of a unilateral arterial fistula in a young patient.