Iatrogenic superficial external pudendal artery pseudoaneurysm: Treatment with doppler us-guided compression

Pseudoaneurysms rarely occur as a serious complication following incomplete hemostasis of an arterial puncture site. As a result of the increase in diagnostic and therapeutic angiography, the frequency of iatrogenic pseudoaneurysm has increased as well. Iatrogenic pseudoaneurysms associated with angiographic catheterization occur most commonly in the common femoral artery. Here we report a case of iatrogenic superficial external pudendal artery (SEPA) pseudoaneurysm following cardiac catheterization, which was diagnosed with Doppler ultrasound (US) and multidetector computed tomographic angiography (MDCTA) before Doppler US-guided compression therapy. To the best of our knowledge, iatrogenic SEPA pseudoaneurysm, which is an unusual vessel location for pseudoaneurysm occurrence, has not been reported in the literature. In patients in whom anticoagulant-thrombolytic therapy or therapeutic catheterization with larger sized sheath is planned, determination of the precise localization of arterial puncture site is important for the prevention of iatrogenic pseudoaneurysm development. Arterial puncture guided with Doppler US might reduce complications. When suspected, MDCTA is useful in the diagnosis and demonstration of iatrogenic pseudoaneurysms. Treatment of US-guided compression should be the first choice for iatrogenic pseudoaneurysms. Interventional radiologists and cardiologists should have enough experience about the catheterization complications and their treatment in order to decrease the morbidity and mortality related to the intervention

Reduction of the Radiofrequency Heating of Metallic Devices Using a Dual-Drive Birdcage Coil

Cataloged from PDF version of article.In this work, it is demonstrated that a dual-drive birdcage coil can be used to reduce the radiofrequency heating of metallic devices during magnetic resonance imaging. By controlling the excitation currents of the two channels of a birdcage coil, the radiofrequency current that is induced near the lead tip could be set to zero. To monitor the current, the image artifacts near the lead tips were measured. The electric field distribution was controlled using a dual-drive birdcage coil. With this method, the lead currents and the lead tip temperatures were reduced substantially [<0.3 C for an applied 4.4 W/kg SAR compared to >4.9 C using quadrature excitation], as demonstrated by phantom and animal experiments. The homogeneity of the flip angle distribution was preserved, as shown by volunteer experiments. The normalized root-mean-square error of the flip angle distribution was less than 10% for all excitations. The average specific absorption rate increased as a trade-off for using different excitation patterns. Magn Reson Med 69:845–852, 2013. VC 2012 Wiley Periodicals, In

Comparison between Capsule Endoscopy and Magnetic Resonance Enterography for the Detection of Polyps of the Small Intestine in Patients with Familial Adenomatous Polyposis

Objective. The objective of this study was to assess the utility of magnetic resonance enterography (MRE) compared with capsule endoscopy (CE) for the detection of small-bowel polyps in patients with familial adenomatous polyposis (FAP). Methods. Patients underwent MRE and CE. The polyps were classified according to size of polyp: <5 mm (small size), 5–10 mm (medium size), or >10 mm (large size). The location (jejunum or ileum) and the number of polyps (1–5, 6–20, >20) detected by CE were also assessed. MRE findings were compared with the results of CE. Results. Small-bowel polyps, were detected by CE in 4 of the 6 (66%) patients. Three patients had small-sized polyps and one patient had medium-sized polyps. CE detected polyps in four patients that, were not shown on MRE. Desmoid tumors were detected on anterior abdominal wall by MRE. Conclusion. In patients with FAP, CE can detect small-sized polyps in the small intestine not seen with MRE whereas MRE yields additional extraintestinal information

Feasibility of 3-dimensional sampling perfection with application optimized contrast sequence in the evaluation of patients with hydrocephalus

Purpose This study aimed to investigate the effectiveness and additive value of T2W 3-dimensional sampling perfection with application optimized contrast (3D-SPACE) with variant flip-angle mode in imaging of all types of hydrocephalus. Our secondary objective was to assess the reliability of 3D-SPACE sequence and correspondence of the results with phase-contrast magnetic resonance imaging (PC-MRI)-based data. Materials and Methods Forty-one patients with hydrocephalus have undergone 3-T MRI. T2W 3D-SPACE sequence has been obtained in addition to routine hydrocephalus protocol. Cerebrospinal fluid circulation, presence/type/etiology of hydrocephalus, obstruction level scores, and diagnostic levels of confidence were evaluated separately by 2 radiologists. In the first session, routine sequences with PC-MRI were evaluated, and in another session, only 3D-SPACE and 3-dimensional magnetization prepared rapid acquisition gradient echo sequences were evaluated. Results obtained in these sessions were compared with each other and those obtained in consensus session. Results Agreement values were very good for both 3D-SPACE and PC-MRI sequences (P < 0.001 for all). Also, the correlation of more experienced reader's 3D-SPACE-based scores and consensus-based scores was perfect (κ = 1, P < 0.001).The mean value of PC-MRI-based confidence scores were lower than those obtained in 3D-SPACE and consensus sessions. Conclusions T2W 3D-SPACE sequence provides morphologic cerebrospinal fluid flow data. It is a noninvasive technique providing extensive multiplanar reformatted images with a lower specific absorption rate. These advantages over PC-MRI make 3D-SPACE sequence a promising tool in management of patients with hydrocephalus. © 2015 Wolters Kluwer Health, Inc

Reduction of the radiofrequency heating of metallic devices using a dual-drive birdcage coil

In this work, it is demonstrated that a dual-drive birdcage coil can be used to reduce the radiofrequency heating of metallic devices during magnetic resonance imaging. By controlling the excitation currents of the two channels of a birdcage coil, the radiofrequency current that is induced near the lead tip could be set to zero. To monitor the current, the image artifacts near the lead tips were measured. The electric field distribution was controlled using a dual-drive birdcage coil. With this method, the lead currents and the lead tip temperatures were reduced substantially [4.9°C using quadrature excitation], as demonstrated by phantom and animal experiments. The homogeneity of the flip angle distribution was preserved, as shown by volunteer experiments. The normalized root-mean-square error of the flip angle distribution was less than 10% for all excitations. The average specific absorption rate increased as a trade-off for using different excitation patterns. Copyright © 2012 Wiley Periodicals, Inc

Investigation of Heschl's gyrus and planum temporale in patients with schizophrenia and bipolar disorder: A proton magnetic resonance spectroscopy study

Background: Superior temporal cortices include brain regions dedicated to auditory processing and several lines of evidence suggest structural and functional abnormalities in both schizophrenia and bipolar disorder within this brain region. However, possible glutamatergic dysfunction within this region has not been investigated in adult patients. Methods: Thirty patients with schizophrenia (38.67 ± 12.46. years of age), 28 euthymic patients with bipolar I disorder (35.32 ± 9.12. years of age), and 30 age-, gender- and education-matched healthy controls were enrolled. Proton magnetic resonance spectroscopy data were acquired using a 3.0. T Siemens MAGNETOM TIM Trio MR system and single voxel Point REsolved Spectroscopy Sequence (PRESS) in order to quantify brain metabolites within the left and right Heschl's gyrus and planum temporale of superior temporal cortices. Results: There were significant abnormalities in glutamate (Glu) (F(2,78) = 8.52, p < 0.0001), N-acetyl aspartate (tNAA) (F(2,81) = 5.73, p = 0.005), creatine (tCr) (F(2,83) = 5.91, p = 0.004) and inositol (Ins) (F(2,82) = 8.49, p < 0.0001) concentrations in the left superior temporal cortex. In general, metabolite levels were lower for bipolar disorder patients when compared to healthy participants. Moreover, patients with bipolar disorder exhibited significantly lower tCr and Ins concentrations when compared to schizophrenia patients. In addition, we have found significant correlations between the superior temporal cortex metabolites and clinical measures. Conclusion: As the left auditory cortices are associated with language and speech, left hemisphere specific abnormalities may have clinical significance. Our findings are suggestive of shared glutamatergic abnormalities in schizophrenia and bipolar disorder. © 2013 Elsevier B.V

Evolution of the γ\gamma-ray strength function in neodymium isotopes

The experimental gamma-ray strength functions (gamma-SFs) of 142,144-151Nd have been studied for gamma-ray energies up to the neutron separation energy. The results represent a unique set of gamma-SFs for an isotopic chain with increasing nuclear deformation. The data reveal how the low-energy enhancement, the scissors mode and the pygmy dipole resonance evolve with nuclear deformation and mass number. The data indicate that the mechanisms behind the low-energy enhancement and the scissors mode are decoupled from each other.Comment: 14 pages and 10 figure

New experimental constraint on the 185^{185}W(n,γn,\gamma)186^{186}W cross section

In this work, we present new data on the $^{182,183,184}$W($\gamma,n$) cross sections, utilizing a quasi-monochromatic photon beam produced at the NewSUBARU synchrotron radiation facility. Further, we have extracted the nuclear level density and $\gamma$-ray strength function of $^{186}$W from data on the $^{186}$W($\alpha,\alpha^\prime\gamma$)$^{186}$W reaction measured at the Oslo Cyclotron Laboratory. Combining previous measurements on the $^{186}$W($\gamma,n$) cross section with our new $^{182,183,184}$W($\gamma,n$) and ($\alpha,\alpha^\prime\gamma$)$^{186}$W data sets, we have deduced the $^{186}$W $\gamma$-ray strength function in the range of $1 < E_\gamma < 6$ MeV and $7 < E_\gamma < 14$ MeV. Our data are used to extract the level density and $\gamma$-ray strength functions needed as input to the nuclear-reaction code \textsf{TALYS}, providing an indirect, experimental constraint for the $^{185}$W($n,\gamma$)$^{186}$W cross section and reaction rate. Compared to the recommended Maxwellian-averaged cross section (MACS) in the KADoNiS-1.0 data base, our results are on average lower for the relevant energy range $k_B T \in [5,100]$ keV, and we provide a smaller uncertainty for the MACS. The theoretical values of Bao \textit{et al.} and the cross section experimentally constrained on photoneutron data of Sonnabend \textit{et al.} are significantly higher than our result. The lower value by Mohr \textit{et al.} is in very good agreement with our deduced MACS. Our new results could have implications for the $s$-process and in particular the predicted $s$-process production of $^{186,187}$Os nuclei.Comment: 17 pages, 15 figures; to be submitted to Phys. Rev.