Prediction of mobilized hematopoietic stem cell yield in patients with multiple myeloma: Usefulness of whole-body MRI-derived indices.

INTRODUCTION: High-dose chemotherapy followed by autologous stem cell transplant is the mainstay of treatment for multiple myeloma (MM). The purpose of this study was to evaluate the ability of MRI-derived indices to predict mobilized hematopoietic stem cell yield. MATERIALS AND METHODS: In this exploratory pilot work, we retrospectively analyzed 38 mobilization procedures for MM. Successful mobilization procedure was defined as a total yield of >4.0×106 CD34+ cells/kg. Univariate and multivariate analyses were performed to identify factors with a significant effect on successful mobilization from among clinical characteristics including number of prior lines of therapy, period from diagnosis to harvest, type of monoclonal protein (M protein); and radiological characteristics including total diffusion volume (tDV), median apparent diffusion coefficient (ADC) of tDV, and mean fat fraction of bone marrow calculated by MRI. RESULTS: Univariate analyses showed that relatively poor mobilization was significantly associated with M protein of Bence-Jones type and with median ADC of tDV (P = 0.02 and P = 0.004, respectively). Multivariate analyses using these two indices showed that median ADC of tDV was a significant predictive factor for adequate mobilization (P = 0.01), with an area under the curve of 0.784 (cutoff value, 1.18×10-3 mm2/s; sensitivity, 72.7%; specificity, 87.5%). CONCLUSION: The present data indicate that median ADC of tDV is a predictive factor for relatively poor mobilization of hematopoietic stem cells in MM patients undergoing autologous stem cell transplant.

Congenital anomalies causing hemato/hydrocolpos: imaging findings, treatments, and outcomes.

Hemato/hydrocolpos due to congenital urogenital anomalies are rare conditions discovered in neonatal, infant, and adolescent girls. Diagnosis is often missed or delayed owing to its rare incidence and nonspecific symptoms. If early correct diagnosis and treatment cannot be performed, late complications such as tubal adhesion, pelvic endometriosis, and infertility may develop. Congenital urogenital anomalies causing hemato/hydrocolpos are mainly of four types: imperforate hymen, distal vaginal agenesis, transverse vaginal septum, and obstructed hemivagina and ipsilateral renal anomaly, and clinicians should have adequate knowledge about these anomalies. This article aimed to review the diagnosis and treatment of these urogenital anomalies by describing embryology, clinical presentation, imaging findings, surgical management, and postoperative outcomes.

The opacity of mineral ion-loaded bead (DC beads®) on low-keV monochromatic images from dual energy CT and T1-weighted gradient-echo MRI.

PURPOSE: To evaluate the opacity of DC beads® (DCB) loaded with mineral ions on low-keV monochromatic images from dual energy computed tomography (DECT) and T1-weighted gradient-echo (T1-GRE) MRI. MATERIALS AND METHODS: Fe2+ or Ca2+-loaded DCBs were prepared by mixing DCBs in 100 mM FeSO4 or CaSO4 solution and scanned by DECT from 10 min to 27 h after mixing. The Hounsfield units (HUs) of sedimented DCBs on 40-keV monochromatic images were measured. Next, we mixed DCBs in 100, 10, 5 and 1 mM FeSO4 solutions, and scanned these solutions from 15 to 120 min after mixing using a 3 T MR scanner. The signal-noise ratios (SNRs) of sedimented DCBs on T1-GRE were measured. Venous blood was scanned to compare with DCBs. RESULTS: The CT values of DCBs in FeSO4 and CaCl2 solutions gradually increased, and were 113.3 and 43.1 HU at 27 h, respectively; that of blood was 17.8 HU. The SNR of DCB in 1 mM FeSO4 solution increased and achieved equilibrium at 120 min, and was 120.5 and higher than in the other FeSO4 solutions. The SNR of blood was 49.7. CONCLUSION: Optimally Fe2+-loaded DCBs can be discriminated from venous blood on 40-keV monochromatic images from DECT and T1-GRE.

Clinical utility of optimized three-dimensional T1-, T2-, and T2*-weighted sequences in spinal magnetic resonance imaging.

This article reviews the clinical utility of 3D magnetic resonance imaging (MRI) sequences optimized for the evaluation of various intraspinal lesions. First, intraspinal tumors with hypervascular components and arteriovenous malformations (AVM) are clearly shown on contrast-enhanced (CE)-3D T1-weighted gradient-echo (GE) sequences with high spatial resolution. Second, dynamic CE-3D time-resolved magnetic resonance angiography (MRA) shows delineated feeding arteries of intraspinal AVM or arteriovenous fistula (AVF), greatly aiding subsequent digital subtraction angiography (DSA). Third, 3D multiecho T2*-weighted GE sequences are used to visualize intraspinal structures and spinal cord lesions and are sensitive to the magnetic susceptibility of intraspinal hemorrhages. Three-dimensional balanced steady-state free precession (SSFP) and multishot 3D balanced non-SSFP sequences produce contiguous thin images with high signal-to-noise ratio (SNR) in short scanning times. Intraspinal cystic lesions and small nerve-root tumors in subarachnoid space can be viewed using 3D balanced SSFP. Spinal cord myelomalacia and cord compression can be evaluated on fat-suppressed multishot 3D balanced non-SSFP. Finally, a 3D T2-weighted fast spin-echo (FSE) sequence with variable flip angle (FA) refocusing pulse improves through-plane spatial resolution over conventional 2D T2-weighted FSE sequences while matching image contrast.

Balloon-occluded retrograde transvenous obliteration of gastric varix with multiple drainage veins performed with temporal occlusion of the pericardiacophrenic vein with a micro-balloon.

We encountered a case with a gastric varix that drained into the gastro-renal shunt, left pericardiacophrenic vein, and several other dilated collateral veins. This patient had a circumaortic venous ring. For this case we successfully performed balloon-occluded retrograde transvenous obliteration in which sclerotic agents were infused from the balloon catheter advanced to the left pre-aortic renal vein and the tip was wedged into the end of the gastro-renal shunt. Before injection of sclerotic agents, collateral veins other than the left pericardiacophrenic vein were embolized with micro-coils. During the injection, the left pericardiacophrenic vein was occluded temporarily with a micro-balloon catheter coaxially advanced from the catheter inserted from the femoral vein to the left pericardiacophrenic vein through the left brachiocephalic vein.

Evaluation of lumber nerve root compression using thin-slice thickness coronal magnetic resonance imaging: three-dimensional fat-suppressed multi-shot balanced non-steady-state free precession versus three-dimensional T1-weighted spoiled gradient-recalled echo.

PURPOSE: The aim of this study was to compare the three-dimensional fat-suppressed balanced non-steady-state free precession (3D FS-nSSFP) sequence and the 3D T1-weighted spoiled gradient-recalled echo (3D T1-GRE) sequence for evaluating lumbar nerve root compression with continuous thin-slice coronal magnetic resonance (MR) images. MATERIALS AND METHODS: The institutional review board approved this study, and written informed consent was obtained from all 35 patients. We optimized continuous 2.5-mm thick lumbar coronal images with 3D FS-nSSFP and 3D T1-GRE. We calculated the contrast-to-noise ratio (CNR) for nerve roots and other structures on images with the two sequences. With knowledge of the final diagnosis, we assessed the visibility of nerve root compression on these images. RESULTS: The CNR values of nerve roots were significantly higher on images with 3D FS-nSSFP than on those with 3D T1-GRE. These continuous thin-slice coronal images facilitated visualization of nerve root compression in >91% of patients. There was no statistically significant difference between the two sequences in the detection of nerve root compression. CONCLUSION: Continuous thin-slice coronal MR images using 3D FS-nSSFP and 3D T1-GRE sequences are sufficient to evaluate lumbar nerve root compression, and 3D FS-nSSFP is superior to 3D T1-GRE for depiction of lumbar nerve roots.