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ABSTRACT Objective To evaluate prospectively the uterine scar after Cesarean section (CS) and the corresponding uterine region after vaginal delivery (VD) at 6 weeks postpartum using transabdominal (TAS) and transvaginal (TVS) sonography with magnetic resonance imaging (MRI) fusion to investigate whether fusion imaging allows standardized and reproducible identification of the scar location and measurement of uterine wall thickness compared with high-resolution MRI alone. Methods Pelvic MRI was performed 6 weeks after delivery in 30 women (10 with planned CS (PCS), 10 with emergency CS (ECS) and 10 with VD). After transfer of MRI-DICOM datasets to the ultrasound system, the scar region after CS and the corresponding uterine region after VD were examined by TAS (5 MHz) and TVS (10 MHz) using smart fusion with MRI to guide visualization of the region in the corresponding sectional planes for both modalities. Vascularization of the scar region was determined as a percentage area using power Doppler ultrasound. Anterior (AW) and posterior (PW) uterine wall thickness was measured using TAS and TVS with fusion imaging and using MRI alone. Results TVS with fusion imaging was applied successfully for uterine assessment at the end of the postpartum period in all women. TAS failed to identify the scar area in three women. Imaging techniques were similar in the evaluation of AW and PW thickness following VD. MRI and MRI/TVS fusion showed significant differences in AW thickness or scar area, in terms of the difference relative to PW thickness, in women with PCS and ECS (MRI: PCS, 4.3 mm; ECS, 4.2 mm; VD, 0.8 mm; P = 0.034; MRI/TVS fusion: PCS, 2.0 mm; ECS, 3.3 mm; VD, 0.0 mm; P = 0.01). The degree of vascularization in the scar region measured by power Doppler ultrasound was lower after PCS (13.1 ± 9.4%/area) and ECS (17.0 ± 8.2%/area) than after VD (34.6 ± 8.5%/area; P = 0.0017). Conclusion MRI/ultrasound fusion imaging can be performed in a reproducible manner for examination of the postpartum uterus. MRI/TVS fusion enables standardized identification of the CS scar location and vascularization is reduced in this area. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Purpose: To test the diagnostic performance of bone SPECT/CT and MRI for the evaluation of bone viability in patients after girdlestone-arthroplasty with histopathology used as gold standard.Materials and Methods: In this cross-sectional study, patients after girdlestone-arthroplasty were imaged with single-photon-emission-computed-tomography/computed-tomography (SPECT/CT) bone-scans using 99mTc-DPD. Additionally, 1.5 T MRI was performed with turbo-inversion-recovery-magnitude (TIRM), contrast-enhanced T1-fat sat (FS) and T1-mapping. All imaging was performed within 24 h prior to revision total-hip-arthroplasty in patients with a girdlestone-arthroplasty. In each patient, four standardized bone-tissue-biopsies (14 patients) were taken intraoperatively at the remaining acetabulum superior/inferior and trochanter major/minor. Histopathological evaluation of bone samples regarding bone viability was used as gold standard.Results: A total of 56 bone-segments were analysed and classified as vital (n = 39) or nonvital (n = 17) by histopathology. Mineral/late-phase SPECT/CT showed a high sensitivity (90%) and specificity (94%) to distinguish viable and nonviable bone tissue. TIRM (sensitivity 87%, specificity 88%) and contrast-enhanced T1-FS (sensitivity 90%, specificity 88%) also achieved a high sensitivity and specificity. T1-mapping achieved the lowest values (sensitivity 82%, specificity 82%). False positive results in SPECT/CT and MRI resulted from small bone fragments close to metal artefacts.Conclusions: Both bone SPECT/CT and MRI allow a reliable differentiation between viable and nonviable bone tissue in patients after girdlestone arthroplasty. The findings of this study could also be relevant for the evaluation of bone viability in the context of avascular bone necrosis. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate how far fracture status and bone mineral density (BMD) correlate with the vascular calcification score (CS). Methods: On 29 complete human cadavers (17 female, 12 male; mean age at death was 85.57 years), multi-detector computed tomography was performed to assess the spine fracture status (fracture vs non-fracture [FX vs non-FX]) and CS of the coronary arteries (Coro-CS), the aorta (Aorta-CS) and the pelvic vessels (Iliac-CS). Quantitative computed tomography of the lumbar spine was performed to estimate overall BMD (osteoporotic [BMD <80 mg/cm] vs non-osteoporotic [BMD ≥80 mg/cm]). Results: Gender-specific differences in statistical significance were only observed for Aorta-CS and Iliac-CS but not for Coro-CS. When comparing the osteoporotic with the non-osteoporotic group, statistically significant differences were only found for Iliac-CS ( P < 0.05); however, linear regression analysis showed none of the CSs to significantly correlate with BMD. Conclusions: In our small post-mortem elderly population, statistically significant associations of fracture status and BMD with CS were only observed between the osteoporotic and non-osteoporotic groups for the pelvic vessels but not for the coronary arteries and the aorta. Key Points: • Gender-specific differences were observed for aortic and iliac calcification score (CS). • There was no difference in coronary CS between females and males. • Only iliac CS was different in osteoporotic and non-osteoporotic subjects. • In linear regression analysis, CS showed no correlation with BMD. • In univariate analysis, gender was a BMD and iliac CS confounder. [ABSTRACT FROM AUTHOR]

Purpose: To compare current technology multislice computed tomography angiography (CTA) with magnetic resonance angiography (MRA) in the pre-operative evaluation of vascular anatomy of living renal transplant donors. Methods and materials: Two hundred and thirty-six kidneys were included in the CTA and MRA analysis. Renal vasculature was evaluated independently by two readers in each modality with a delay of 4 weeks between reading sessions. Surgical correlation on the operated side was available in all patients. The reference standard was defined by surgical correlation and consensus reading of both modalities. Results: Detection rate of CTA for arteries was 99.1 and 95.0 % for reader 1 and reader 2, respectively. Detection rate of MRA for arteries was 95.0/94.3 %. Most of the undetected arteries were ≤1 mm diameter (reader 1: 2 of 3 in CTA and 9 of 16 in MRA; reader 2: 11 of 16 in CTA, and 8 of 18 in MRA). Detection rates for arteries ≥2 mm for reader 1/reader 2 were 99.7/98.7 % in CTA and 99.1/97.8 % in MRA, respectively. Detection rates for veins were 99.6/97.4 % in CTA and 97.8/96.9 % in MRA, respectively. Both readers misdiagnosed between 0 and 1 non-present arteries and between 2 and 3 non-present veins in both modalities. Conclusions: Modern multislice CT and MRI scanners allow highly accurate evaluation of the vascular anatomy, especially for vessels of ≥2 mm diameter. CTA may provide slightly better depiction of very small arteries; however, this may be reader-dependent. Additional factors affecting the choice of imaging modality should include local availability, cost, and the desire to avoid ionizing radiation in healthy transplant donors. [ABSTRACT FROM AUTHOR]

Objectives: Assessment of cartilage lesions and osteoarthritis (OA) of the patellofemoral joint in patients following lateral patellar dislocation using magnetic resonance imaging (MRI).Methods: MR images of 129 knees (mean age 26 years, range 11-56) grouped as acute (A), recurrent (B), and chronic (C) dislocators were analysed regarding the prevalence and severity of patellofemoral cartilage lesions. Grades of OA were assessed using modified WORMS.Results: In groups A, B, and C the prevalence of cartilage lesions was 71%, 82%, and 97%, respectively. Most lesions were located on the central patella in groups A and B (central 69% and 78%; medial 56% and 47%; lateral 31% and 42%), whereas group C revealed all regions affected (73%, 61%, and 67%). Of group A, 14% had mild OA and 64% of group B. Group C showed mild OA in 62% and moderate OA in 18%. Cartilage defect size and prevalence of OA was correlated with number of dislocations (r = 0.41 and r = 0.59; P < 0.001).Conclusions: Cartilage lesions and early OA are common after patellar dislocation and appear to increase with the frequency of dislocation. Both conditions should be considered when interpreting MRI in such patients, because of implications for treatment.Key Points: • Cartilage lesions are very common after patellar dislocation. • The severity of cartilage lesions increases with number of dislocations. • Osteoarthritis is common after recurrent patellar dislocation, even in young patients. • Detecting cartilage lesions is important after patellar dislocation. [ABSTRACT FROM AUTHOR]

Summary: Radiographs and spinal bone mineral density (BMD) were evaluated from 342 elderly men regarding possible effects of diffuse idiopathic skeletal hyperostosis (DISH) on vertebral fractures and densitometry measurements. Prevalent vertebral fractures were more frequent among men with DISH compared to men with no DISH even after fracture prevalence was adjusted for BMD. Paravertebral calcifications should be considered in patients with DISH when interpreting BMD measurements because both dual X-ray absorptiometry (DXA) and quantitative CT (QCT) densitometry may not be reliable. Introduction: The purpose of this study is to evaluate the prevalence of DISH in older men and its association with vertebral fractures and with BMD determined by DXA and QCT. Methods: Lateral radiographs of the spine were analyzed in a sample of 342 men aged ≥65 years participating in the MrOS Study concerning the presence and grade of DISH and vertebral fractures. Lumbar BMD was measured by both DXA (areal, grams per square centimeter) and QCT (volumetric, grams per cubic centimeter). The association between DISH, BMD, and presence of fractures was studied using χ and t tests. Results: DISH was present in 52% (178/342) of the men. Men with DISH were older (mean, 75.1 vs 73.3, p < 0.05) and more likely to have prevalent fractures (28% vs 20%, p < p = 0.09). BMD assessed with DXA (1.08 vs 1.00 g/cm, p ≤ 0.0001), but not with QCT (0.11 vs 0.11 g/cm3, p = 0.65), was significantly higher in men with DISH compared to men without DISH. Significantly lower BMD of men with both DISH and fractures compared to men with DISH but without fractures was only detected by QCT (−25%, 0.09 vs 0.12, p < 0.05). Both DXA BMD and QCT BMD were significantly higher in severe lumbar DISH (+22% and +31%, p < 0.0001), respectively. Conclusion: DISH was associated with a higher prevalence of vertebral fractures in elderly men. Lumbar ossifications related to DISH should be considered when interpreting BMD measurements to predict their fracture risk. [ABSTRACT FROM AUTHOR]

Objectives: The aim of our study was to perform trabecular bone structure analysis with images from 64- and 320-slice multidetector computed tomography (MDCT) and to compare these with high-resolution peripheral computed tomography (HR-pQCT).Materials and Methods: Twenty human cadaver distal forearm specimens were imaged on a 64- and 320-slice MDCT system at 120 kVp, 200 mA and 135 kVp, 400 mA (in-plane pixel size 234 microm; slice thickness 500 microm). HR-pQCT imaging was performed at an isotropic voxel size of 41 microm. Bone volume fraction (BV/TV), trabecular number (Tb.N), thickness (Tb.Th) and separation (Tb.Sp) were computed.Results: MDCT-derived BV/TV and Tb.Sp were highly correlated (r = 0.92-0.96, p < 0.0001) with the corresponding HR-pQCT parameters. Tb.Th was the only structure measure that did not yield any significant correlation.Conclusion: The 64- and 320-slice MDCT systems both perform equally well in depicting trabecular bone architecture. However, because of constrained resolutions accurate derivation of trabecular bone measures is limited to only a subset of microarchitectural parameters. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate several substances regarding small bowel distension and contrast on balanced steady‐state free precession (bSSFP) cine magnetic resonance (MR) images.Material and Methods: Luminal contrast was evaluated in 24 volunteers after oral application of two different contrast agent groups leading to either bright lumen (pineapple, blueberry juice) or dark lumen (tap water, orange juice) on T1‐weighted images. Bowel distension was evaluated in 30 patients ingesting either methylcellulose or mannitol solution for limiting intestinal absorption. Fifteen patients with duodeno‐jejunal intubation served as the control. Quantitative evaluation included measurement of luminal signal intensities and diameters of four bowel segments, qualitative evaluation assessed luminal contrast and distension on a five‐point scale.Results: Quantitative and qualitative evaluation of the four contrast agents revealed no significant differences regarding luminal contrast on bSSFP images. Quantitative evaluation revealed significantly lower (P<0.05) small bowel distension for three out of four segments (qualitative evaluation: two out of four segments) for methylcellulose in comparison to the control. Mannitol was found to be equal to the control.Conclusion: Oral ingestion of tap water or orange juice in combination with mannitol is recommended for cine MR imaging of the small bowel regarding luminal contrast and small bowel distension on bSSFP sequences. [ABSTRACT FROM AUTHOR]

Objective: To evaluate prospectively the uterine scar after Cesarean section (CS) and the corresponding uterine region after vaginal delivery (VD) at 6 weeks postpartum using transabdominal (TAS) and transvaginal (TVS) sonography with magnetic resonance imaging (MRI) fusion to investigate whether fusion imaging allows standardized and reproducible identification of the scar location and measurement of uterine wall thickness compared with high-resolution MRI alone.Methods: Pelvic MRI was performed 6 weeks after delivery in 30 women (10 with planned CS (PCS), 10 with emergency CS (ECS) and 10 with VD). After transfer of MRI-DICOM datasets to the ultrasound system, the scar region after CS and the corresponding uterine region after VD were examined by TAS (5 MHz) and TVS (10 MHz) using smart fusion with MRI to guide visualization of the region in the corresponding sectional planes for both modalities. Vascularization of the scar region was determined as a percentage area using power Doppler ultrasound. Anterior (AW) and posterior (PW) uterine wall thickness was measured using TAS and TVS with fusion imaging and using MRI alone.Results: TVS with fusion imaging was applied successfully for uterine assessment at the end of the postpartum period in all women. TAS failed to identify the scar area in three women. Imaging techniques were similar in the evaluation of AW and PW thickness following VD. MRI and MRI/TVS fusion showed significant differences in AW thickness or scar area, in terms of the difference relative to PW thickness, in women with PCS and ECS (MRI: PCS, 4.3 mm; ECS, 4.2 mm; VD, 0.8 mm; P = 0.034; MRI/TVS fusion: PCS, 2.0 mm; ECS, 3.3 mm; VD, 0.0 mm; P = 0.01). The degree of vascularization in the scar region measured by power Doppler ultrasound was lower after PCS (13.1 ± 9.4%/area) and ECS (17.0 ± 8.2%/area) than after VD (34.6 ± 8.5%/area; P = 0.0017).Conclusion: MRI/ultrasound fusion imaging can be performed in a reproducible manner for examination of the postpartum uterus. MRI/TVS fusion enables standardized identification of the CS scar location and vascularization is reduced in this area. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]