Development of a novel lipidic nanoparticle probe using liposomal encapsulated Gd2O3-DEG for molecular MRI.

Recently, it has been showed that gadolinium oxide nanoparticles can provide high-contrast enhancement in magnetic resonance imaging (MRI). Moreover, liposomes due to high biocompatibility have shown unique model systems, with the most successful application being the drug delivery system. As a suitable cell-tracking contrast agent (CA) in molecular MRI (mMRI), the synthesis and optimisation characteristic of a novel paramagnetic liposomes (PMLs) based on gadolinium nanoparticles, essentially composed of a new complex of gadolinium oxide-diethylene glycol (Gd2O3-DEG) loaded in liposomes have been determined in this research. Gd2O3-DEG was prepared by a new supervised polyol method and was encapsulated with liposome by the film hydration method. The paramagnetic liposome nanoparticle (PMLN) sizes ranged from 65 to 170 nm. The r1 of PMLNs and Gd2O3-DEG were much higher than that of Gd-diethylenetriamine penta-acetic acid (Gd-DTPA). In MC/9 cell lines, the experiments showed similar results as in water. PMLNs with lower T1 than Gd-DTPA are sensitive, positive MRI CA that could be attractive candidates for cellular and molecular lipid content targets such as diagnostic applications.

Traumatic dissecting posterior cerebral artery aneurysm. A case report and review of the literature.

Dissecting posterior cerebral artery (PCA) aneurysms are among rare cerebrovascular malformations accounting for 2% to 6% of all aneurysms. Herein we describe a case of pediatric dissecting aneurysm located in the PCA with documentation of aneurysm development. In addition, we discuss its treatment with a new therapeutic method involving glue injection.

1-hexyl n-cyanoacrylate compound (Neucrylate™ AN), a new treatment for berry aneurysm. III: Initial clinical results.

INTRODUCTION: As part of an institutionally approved research protocol, patients with cerebral berry aneurysm were enrolled in a clinical trial designed to evaluate the safety of the new moldable liquid embolic agent Neucrylate AN. METHODS: Twelve patients with aneurysms judged to be suboptimal for treatment by standard endovascular or surgical approaches were treated with Neucrylate AN. The agent was injected during temporary balloon occlusion at the neck of the aneurysm. The immediate angiographic percentage of aneurysm occlusion and periprocedural adverse events were assessed for each patient. Six-month follow-up angiographic studies were obtained for nine of the 12 patients. RESULTS: Ten of the 12 aneurysms treated (83%) were large to giant (>1.0 cm in diameter), nine (75%) were wide-necked (dome/neck ratio <2.0) and three (25%) were dissecting aneurysms. There were four (33%) periprocedural neurological events. Immediate aneurysm occlusion of >90% was obtained in nine of the 12 cases (75%). There were five recurrences (55.5%) at 6 months. CONCLUSION: This preliminary clinical series shows that it is feasible to achieve a high percentage of immediate aneurysm occlusion with limited patient morbidity and mortality in the setting of morphologically challenging aneurysms. These preliminary data support larger trials assessing the safety and efficacy of this agent.

Diagnostic Accuracy of Sixty Four Multi-Slice CT Angiography in Assessment of Arterial Cut-Off and Run-Off in Comparison with Surgical Findings.

BACKGROUND/OBJECTIVE: The accurate anatomic mapping and determination of the severity of arterial disease, an important health problem of the elderly, is of great significance. We aimed to determine the diagnostic value of 64-multislice CT angiography (MSCTA) in run-off and cut-off sites of arterial disease. PATIENTS AND METHODS: Throughout the study, MSCTA followed by an operative intervention was carried out on a total of 38 patients with clinical signs and symptoms suggestive of arterial disease (AD) all of whom had the indication for vascular surgery. The mean age of patients was 34±15.86 (range, 23 to 93) years. MSCTA was executed using a 64-slice CT scanner, during the arterial phase of injecting the nonionic, contrast medium with a power injector at the rate of 5 ml/sec into the antecubital vein and exploration and revascularization of peripheral arterial disease was performed intraoperatively. RESULTS: Atherosclerosis and arterial disease, the most common causes of vascular occlusion, were more common in the lower extremities. According to MSCTA findings, the most frequent site of stenosis was the superficial femoral artery. Spearman's correlation coefficient showed a high degree of agreement amongst the raters. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and the accuracy of MSCTA compared to surgery were 83.8%, 96%, 96.8%, 81.3% and 89%, respectively. MSCTA findings were compared with surgery as a standard of reference, which showed concordance in the majority of cases (81.6%). Cut-off sites were correctly identified by MSCTA in 97.3% of the patients and the most common sites of discordance were the run-off sites (18.2%). CONCLUSION: MSCTA angiography as a novel diagnostic modality may be a suitable alternative and a viable choice for routine clinical diagnosis.

Increasing exophthalmia after carotid-cavernous fistula closure with a detachable balloon: problems of incomplete treatment. A case report.

A 30-year-old woman with pulsating exophthalmia due to posttraumatic carotid-cavernous fistula underwent embolization with a detachable balloon. Because of balloon dislodgement, the drainage was derived to the superior ophthalmic vein and clinical worsening occurred. Complete ophthalmoplegia developed and visual acuity decreased. After a second embolization we inserted two balloons but the same findings were exaggerated. Finally coiling of the internal carotid artery was done and orbital decompression achieved. Ophthalmoplegia, proptosis, chemosis and nerve paralysis intraocular pressure improved.

Evaluation of angiographic findings in spontaneous aneurysmal subarachnoid hemorrhage patients.

This paper describes the angiographic findings of spontaneous aneurysmal subarachnoid hemorrhage (SAH) patients, including frequency, anatomic location and multiplicity of cerebral aneurysms. We retrospectively reviewed the records of 796 SAH patients at our university affiliated hospital. After confirming SAH by lumbar puncture or CT scan, all patients underwent digital subtraction angiography to find the definite anatomic location. The male to Female ratio in SAH patients was 9:10. The mean (SD) age of all patients with SAH was 47.9±14.7 years. The mean (SD) age of men with SAH was 46.6 ±15.6 years and women with SAH was 49.3±13.5 years (P=0.015). 357 (44.8%) patients had aneurysms. The mean (SD) age of aneurysmal patients was 49.8±14.3 years. The mean (SD) age of men with aneurysm was 47.8 ±15.9 years and women with aneurysm was 51.3±12.9 years (P= 0.03). The male to female ratio in aneurysms was 0.72:1. The most common aneurysm location was in the anterior communicating artery (N=166, 39%). The second most common anatomic location was the middle cerebral artery bifurcation (66 left, 60 right). The total number of patients with single aneurysms was 303 (84.9%) while 54 (15.1%) patients had multiple aneurysms. Among these patients, 49 had two aneurysms, three had three aneurysms and two had four aneurysms. In all, 418 aneurysms were detected. Of 357 patients with aneurysms 150 (42%) had vasospasm during angiography. In conclusion, the most common aneurysm location was the anterior communicating artery and the rate of multiplicity was also higher in our patients.

Optimization of MR-Relaxometry for BMD-measurements and its Correlation with DEXA.

The aim of this study was to optimize MRI conventional protocols for BMD measurements using MR-Relaxometry in systems not facilitated with special multi echo protocols. Since, cortical and trabecular bone separation can not be performed in DEXA, so the results might lead to erroneous interpretation of BMD values. One method for bone quality determination is MR relaxometry that derives R2(=1/T2), R2*(=1/T2*) and R2'(=R2*-R2). This study was performed by 1.5T MRI system(Picker Vista-Q800), an uniformity phantom(1.25gr/l CuSO4, with T2=200ms for calibration), a body RF-Coil, 7 normal, 7 osteopenia, 7 osteoporosis volunteers and Lunar DEXA system(DPX-MD). To determine R2*and R2, multi GE and SE protocols with different TE/TR were used. Then in phantom and in coronal section of femoral-neck, relaxation rates were compared with BMD. The slope of neperian-logarithm of signal vs. TE in GE as -R2*used for protocol optimization. Therefore, for phantom calibration, optimized GE parameters of TE=13.42/18/26.8 ms, TR=800ms and ST=8mm used for the measurement of R2*, while, the measurement of R2 required the optimized SE parameters of TE=30/60/90/120ms, TR=800ms and ST=8mm, with CV(R2*)=2.96%, CV(R2)=3%, respectively. In volunteers for SE, TE of 36/54/63/72ms and TR=800ms were used, while, for GE the TEs/TR were the same as those of phantom study. R2*and R2' showed a significant positive correlation with BMD, r=0.62(p<0.05) & r=0.62(p<0.05) respectively. Finally, in accordance with DEXA values, the results showed that MR-Relaxometry is a proper tool for BMD-measurements in femoral-neck. Also it may be used as a complement method for DEXA failure in BMD-assessments.