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Background: Evaluation of kidney function in newborns with hydronephrosis is important for clinical decisions. Dynamic contrast-enhanced (DCE) MRI can provide the necessary anatomical and functional information. Golden angle dynamic radial acquisition and compressed sensing reconstruction provides sufficient spatiotemporal resolution to achieve accurate parameter estimation for functional imaging of kidneys. However, bulk motion during imaging (rigid or nonrigid movement of the subject resulting in signal dropout) remains an unresolved challenge., Purpose: To evaluate a motion-compensated (MoCo) DCE-MRI technique for robust evaluation of kidney function in newborns. Our method includes: 1) motion detection, 2) motion-robust image reconstruction, 3) joint realignment of the volumes, and 4) tracer-kinetic (TK) model fitting to evaluate kidney function parameters., Study Type: Retrospective., Subjects: Eleven newborn patients (ages <6 months, 6 female)., Field Strength/sequence: 3T; dynamic "stack-of-stars" 3D fast low-angle shot (FLASH) sequence using a multichannel body-matrix coil., Assessment: We evaluated the proposed technique in terms of the signal-to-noise ratio (SNR) of the reconstructed images, the presence of discontinuities in the contrast agent concentration time curves due to motion with a total variation (TV) metric and the goodness of fit of the TK model, and the standard variation of its parameters., Statistical Tests: We used a paired t-test to compare the MoCo and no-MoCo results., Results: The proposed MoCo method successfully detected motion and improved the SNR by 3.3 (P = 0.012) and decreased TV by 0.374 (P = 0.017) across all subjects. Moreover, it decreased nRMSE of the TK model fit for the subjects with less than five isolated bulk motion events in 6 minutes (mean 1.53, P = 0.043), but not for the subjects with more frequent events or no motion (P = 0.745 and P = 0.683)., Data Conclusion: Our results indicate that the proposed MoCo technique improves the image quality and accuracy of the TK model fit for subjects who present isolated bulk motion events., Level of Evidence: 3 Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2020;52:207-216., (© 2019 International Society for Magnetic Resonance in Medicine.)

We report our experience with the use of a USCI Sones catheter curve A type 1 (7540) to cross the aortic valves of 45 patients with clinically significant aortic stenosis. The technique was successful in all our patients with a fluoroscopic time of less than 3 min. A gradient of up to 200 mmHg across the aortic valve area was recorded, and the smallest valve area calculated was less than 0.2 cm2. The method obviated the need for a guidewire and satisfactory left ventriculograms were obtained. No major complication was observed. We conclude that the technique is a simple, rapid, and safe means of obtaining left ventricular hemodynamic and angiographic information in patients with aortic stenosis of various degrees of severity.

When retrograde catheterisation and angiography of the ascending aorta from the brachial or femoral approach is not possible, this can be accomplished by direct percutaneous left ventricular puncture. The haemodynamic and angiographic information obtained was essential to surgical correction of aortic arch anomalies as illustrated in two patients.