The clinical outcome of balloon-assisted maturation procedure between autogenous radiocephalic fistula and brachiocephalic fistula in a single-center experience.

OBJECTIVE: Balloon-assisted maturation (BAM) by an endovascular method plays an important role in treating an immature arteriovenous fistula. However, the results between radiocephalic fistula and brachiocephalic fistula were rarely reported. This retrospective study aimed to investigate the effectiveness and outcome of BAM in different sites of autogenous arteriovenous fistulas. METHODS: This single-center retrospective study included patients who underwent BAM procedures from January 2015 to December 2016. Of 148 patients, 117 and 31 patients had a radiocephalic fistula (RC) and a brachiocephalic fistula (BC), respectively. The primary outcome was BAM success. Data regarding fistula lesions, balloon types and size, frequency of procedures, and maturation time were collected for BAMs. The secondary outcome was the patency of a fistula in the follow-up period. RESULTS: No difference was observed in procedure of BAM frequency between the RC and BC groups. The total success rate was 77.7%, without significant difference between the RC and BC groups (81.20% vs 64.50%; P = .055). Within the procedures, the culprit lesion of juxta-anastomosis segment (73.5% vs 25.5%; P < .001) and arterial inlet (21.2% vs 7.8%; P = .04) were more common in the RC group, whereas the venous outlet was more common in the BC group (88.2% vs 57.7%; P < .001). Both groups had an equivalent patency rate after the BAM within the follow-up period (P = .272). CONCLUSIONS: BAM was an effective procedure for immature fistulas, without significant difference between RCs and BCs. Through the procedure, the culprit lesions causing non-maturation were found to be different between the two groups. The patency rate between the two groups after surgery seems to be equivalent within the follow-up period.

A new nano-sized iron oxide particle with high sensitivity for cellular magnetic resonance imaging.

PURPOSE: In this study, we investigated the labeling efficiency and magnetic resonance imaging (MRI) signal sensitivity of a newly synthesized, nano-sized iron oxide particle (IOP) coated with polyethylene glycol (PEG), designed by Industrial Technology Research Institute (ITRI). PROCEDURES: Macrophages, bone-marrow-derived dendritic cells, and mesenchymal stem cells (MSCs) were isolated from rats and labeled by incubating with ITRI-IOP, along with three other iron oxide particles in different sizes and coatings as reference. These labeled cells were characterized with transmission electron microscopy (TEM), light and fluorescence microscopy, phantom MRI, and finally in vivo MRI and ex vivo magnetic resonance microscopy (MRM) of transplanted hearts in rats infused with labeled macrophages. RESULTS: The longitudinal (r (1)) and transverse (r (2)) relaxivities of ITRI-IOP are 22.71 and 319.2 s(-1) mM(-1), respectively. TEM and microscopic images indicate the uptake of multiple ITRI-IOP particles per cell for all cell types. ITRI-IOP provides sensitivity comparable or higher than the other three particles shown in phantom MRI. In vivo MRI and ex vivo MRM detect punctate spots of hypointensity in rejecting hearts, most likely caused by the accumulation of macrophages labeled by ITRI-IOP. CONCLUSION: ITRI-IOP, the nano-sized iron oxide particle, shows high efficiency in cell labeling, including both phagocytic and non-phagocytic cells. Furthermore, it provides excellent sensitivity in T(2)*-weighted MRI, and thus can serve as a promising contrast agent for in vivo cellular MRI.

Reversible postvaccination paraneoplastic encephalomyelitis in a patient with lung adenocarcinoma.

Encephalomyelitis occurs in paraneoplastic syndrome and acute disseminated encephalomyelitis through different autoimmune mechanisms. No postvaccinal encephalomyelitis other than acute disseminated encephalomyelitis has been reported in patients with malignancy. A 68-year-old woman was admitted because of a headache followed by a gait disturbance and psychomotor retardation 2 days after she had received an influenza vaccination followed by abulia, limb rigidity and hyperreflexia of both legs, and meningeal irritation. Cerebrospinal fluid studies showed increased intracranial pressure, elevated immunoglobulins G and A, and pleocytosis. Contrasted brain magnetic resonance imaging revealed ventriculomegaly and multiple symmetric leptomeningeal enhancement, without demyelinating changes or cortical ribbon signs. Somatosensory evoked potentials and nerve conduction velocity studies suggested myelitis. Encephalomyelitis was diagnosed on the basis of clinical and laboratory examinations. The etiological survey identified a lung adenocarcinoma. Both the encephalomyelitis and the lung adenocarcinoma simultaneously progressed after the vaccination and then, after targeted therapy for lung cancer, simultaneously subsided. In conclusion, postinfluenza-vaccination paraneoplastic encephalomyelitis may occur in patients with lung adenocarcinoma.

Sensitive and automated detection of iron-oxide-labeled cells using phase image cross-correlation analysis.

Superparamagnetic iron oxide (SPIO) nanoparticles are increasingly being used to noninvasively track cells, target specific molecules and monitor gene expression in vivo. Contrast changes that are subtle relative to intrinsic sources of contrast present a significant detection challenge. Here, we describe a postprocessing algorithm, called Phase map cross-correlation Detection and Quantification (PDQ), with the purpose of automating identification and quantification of localized accumulations of SPIO agents. The method is designed to sacrifice little flexibility - it works on previously acquired data and allows the use of conventional high-SNR pulse sequences with no extra scan time. We first investigated the theoretical detection limits of PDQ using a simulated dipole field. This method was then applied to three-dimensional (3D) MRI data sets of agarose gel containing isolated dipoles and ex vivo transplanted allogenic rat hearts infiltrated by numerous iron-oxide-labeled macrophages as a result of organ rejection. A simulated dipole field showed this method to be robust in very low signal-to-noise ratio images. Analysis of agarose gel and allogenic rat heart shows that this method can automatically identify and count dipoles while visualizing their biodistribution in 3D renderings. In the heart, this information was used to calculate a quantitative index that may indicate its degree of cellular infiltration.