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The purpose of this study is to assess segmentation reproducibility of artificial intelligence-based algorithm, TotalSegmentator, across 34 anatomical structures using multiphasic abdominal CT scans comparing unenhanced, arterial, and portal venous phases in the same patients. A total of 1252 multiphasic abdominal CT scans acquired at our institution between January 1, 2012, and December 31, 2022, were retrospectively included. TotalSegmentator was used to derive volumetric measurements of 34 abdominal organs and structures from the total of 3756 CT series. Reproducibility was evaluated across three contrast phases per CT and compared to two human readers and an independent nnU-Net trained on the BTCV dataset. Relative deviation in segmented volumes and absolute volume deviations (AVD) were reported. Volume deviation within 5% was considered reproducible. Thus, non-inferiority testing was conducted using a 5% margin. Twenty-nine out of 34 structures had volume deviations within 5% and were considered reproducible. Volume deviations for the adrenal glands, gallbladder, spleen, and duodenum were above 5%. Highest reproducibility was observed for bones (- 0.58% [95% CI: - 0.58, - 0.57]) and muscles (- 0.33% [- 0.35, - 0.32]). Among abdominal organs, volume deviation was 1.67% (1.60, 1.74). TotalSegmentator outperformed the reproducibility of the nnU-Net trained on the BTCV dataset with an AVD of 6.50% (6.41, 6.59) vs. 10.03% (9.86, 10.20; p < 0.0001), most notably in cases with pathologic findings. Similarly, TotalSegmentator's AVD between different contrast phases was superior compared to the interreader AVD for the same contrast phase (p = 0.036). TotalSegmentator demonstrated high intra-individual reproducibility for most abdominal structures in multiphasic abdominal CT scans. Although reproducibility was lower in pathologic cases, it outperforms both human readers and a nnU-Net trained on the BTCV dataset., (© 2024. The Author(s).)

Objectives: To evaluate an optimized deep leaning-based image post-processing technique in lumbar spine MRI at 0.55 T in terms of image quality and image acquisition time., Materials and Methods: Lumbar spine imaging was conducted on 18 patients using a 0.55 T MRI scanner, employing conventional (CDLR) and advanced (ADLR) deep learning-based post-processing techniques. Two musculoskeletal radiologists visually evaluated the images using a 5-point Likert scale to assess image quality and resolution. Quantitative assessment in terms of signal intensities (SI) and contrast ratios was performed by region of interest measurements in different body-tissues (vertebral bone, intervertebral disc, spinal cord, cerebrospinal fluid and autochthonous back muscles) to investigate differences between CDLR and ADLR sequences., Results: The images processed with the advanced technique (ADLR) were rated superior to the conventional technique (CDLR) in terms of signal/contrast, resolution, and assessability of the spinal canal and neural foramen. The interrater agreement was moderate for signal/contrast (ICC = 0.68) and good for resolution (ICC = 0.77), but moderate for spinal canal and neuroforaminal assessability (ICC = 0.55). Quantitative assessment showed a higher contrast ratio for fluid-sensitive sequences in the ADLR images. The use of ADLR reduced image acquisition time by 44.4%, from 14:22 min to 07:59 min., Conclusions: Advanced deep learning-based image reconstruction algorithms improve the visually perceived image quality in lumbar spine imaging at 0.55 T while simultaneously allowing to substantially decrease image acquisition times., Clinical Relevance: Advanced deep learning-based image post-processing techniques (ADLR) in lumbar spine MRI at 0.55 T significantly improves image quality while reducing image acquisition time., Competing Interests: The authors of this manuscript have nothing to disclose. The article comprises original data which has not been previously published in another publication., (© 2024 The Authors.)

Background: The new radial volumetric encoding RAVE-T 2 /T 1 hybrid sequence is a modern three-dimensional sequence with multiparametric approach, which includes T 2 - and T 1 -weighted contrasts obtained in identical slice position during one measurement. However, the RAVE-T 2 /T 1 hybrid sequence is not yet being used in clinical routine., Purpose: The aim of this study was to evaluate the RAVE-T 2 /T 1 hybrid sequence in a pediatric population with a clinical indication for an abdominal MRI examination to demonstrate that the hybrid imaging may be less challenging to perform on children., Materials and Methods: Our retrospective observational study included pediatric patients of all age groups and required for an abdominal MRI examination. Non-contrast standard axial T 1 DIXON and non-contrast RAVE-T 2 /T 1 hybrid sequence were obtained at 3 T. MRI studies were analyzed independently by two pediatric radiologists using a 5-point Likert-type scale in five different categories. T 1 - and T 2 -weighted sequences were each compared with the RAVE-T 2 /T 1 -sequence using a Wilcoxon signed-rank test., Results: The analysis included 15 children (mean age, 11 years and 4 months, 7 girls and 8 boys). The Cohens Kappa of interrater agreement measured 0.62. The T 2 weighted part of the RAVE-T 2 /T 1 sequence was significantly better than the standard T 2 HASTE sequence in four of five image quality categories: overall image quality (2.2 ± 0.7 vs 1.8 ± 0,7, p = 0.03), respiratory motion artefacts (3.8 ± 0.4 vs 2.0 ± 0.7, p <= 0.01), portal vein clarity (3.3 ± 0.8 vs 2.2 ± 0.7, p <= 0.01), hepatic margin sharpness (2.4 ± 1,0 vs 1.8 ± 0.7, p <= 0.01). The T 1 weighted part of the RAVE-T 2 /T 1 sequence was significantly better than the standard T 1 DIXON weighted sequence in three of five image quality categories: respiratory motion artefacts (4.0 ± 0.2 vs 3.6 ± 0.8, p = 0.01), portal vein clarity (2.7 ± 0.9 vs 2.1 ± 0.7, p <= 0.01), hepatic margin sharpness (3.2 ± 0.7 vs 2.6 ± 0.9, p <= 0.01)., Conclusions: The RAVE-T 2 /T 1 hybrid sequence is feasible and equal compared to standard T 1 - and T 2 -weighted sequences in the assessment of abdominal organs in a pediatric population. Due to non-inferiority to the current standard sequences for abdominal imaging, the RAVE-T 2 /T 1 hybrid sequence is a good alternative for children who cannot be examined in breath-hold technique., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Introduction An anterior approach to lumbar interbody fusion is a widely utilized method of access to the lumbar spine. Due to the potential for vascular complications with spine exposure, vascular surgeons are frequently included in the care of these patients as part of a team-based approach. Identifying risk factors for such complications is difficult and not well-defined in the literature. In this investigation, we evaluate the potential risk factors for complications during anterior lumbar inter-body fusion (ALIF). Methods This is a retrospective review of 106 patients who underwent ALIF at a single institution between May 1, 2007, and April 30, 2017. Patients were identified through operating room case logs and Current Procedural Terminology (CPT) codes correlating with ALIF. Vascular surgeons performed all anterior exposures. Patient demographics and data regarding their surgical care and postoperative course were obtained from a review of operative and progress notes in the electronic medical record. Statistical methods employed included a t-test for normally distributed data and the Wilcoxon rank-sum test for non-normally distributed data. Categorical variables were compared using Fisher's exact and chi-square tests. A logistic regression model was applied to predict complications by controlling other significant covariates. Results Of the 106 patients included in this analysis, 16 patients experienced a defined complication, giving an overall complication rate of 15%. Patients with complications were more likely to be of male gender (n=11, P=0.016), with older average age (54.6, P=0.017), with higher estimated blood loss, with higher use of blood products, and with higher use of cell-saver. A venous injury was the most common complication (n=11, 10.4%); ileus and nerve injury were the next most common (n=3, 2.8%). The 30-day mortality was 0%. Male gender demonstrated an odds ratio of 3.78 (P=0 .034) in a logistic regression model after adjusting for age and blood products. Conclusions Overall complication rates were comparable to those in the published literature and male gender was identified as a predictor for risk of complications in those undergoing ALIF. This is the first study to identify male sex as a risk factor for complications following ALIF. The results of this study will hopefully guide future studies in gaining more insight into the predictors of complications in larger series., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2021, Wert et al.)

Purpose: To evaluate vessel assessment in virtual monoenergetic images (VMI 40keV ) and virtual-non-contrast images (VNC) derived from venous phase spectral detector computed tomography (SDCT) acquisitions in comparison to arterial phase and true non-contrast (TNC) images., Methods: Triphasic abdominal SDCT was performed in 25 patients including TNC, arterial and venous phase. VMI 40keV and VNC were reconstructed from the venous phase and compared to conventional arterial-phase images (CI art ), TNC and conventional venous-phase images (CI ven ). Vessel contrast and virtual contrast removal were analyzed with region-of-interest-based measurements and in a qualitative assessment., Results: Quantitative analysis revealed no significant attenuation differences between TNC and VNC in arterial vessels (p-range 0.07-0.47) except for the renal artery (p = 0.011). For venous vessels, significant differences between TNC and VNC were found for all veins (p < 0.001) except the inferior vena cava (p = 0.26), yet these differences remained within a 10 HU range in most patients. No significant attenuation differences were found between CI art /VMI 40keV in arterial vessels (p-range 0.06-0.86). Contrast-to-noise ratio provided by VMI 40keV and CI art was equivalent for all arterial vessels assessed (p-range 0.14-0.91). Qualitatively, VMI 40keV showed similar enhancement of abdominal and pelvic arteries as CI art and VNC were rated comparable to TNC., Conclusion: Our study suggests that VNC and VMI 40keV derived from single venous-phase SDCT offer comparable assessment of major abdominal vessels as provided by routine triphasic examinations, if no dynamic contrast information is required.

Amiodarone accumulates in the liver, where it increases x-ray attenuation due to its iodine content. We evaluated liver attenuation in patients treated and not treated with amiodarone using true-non-contrast (TNC) and virtual-non-contrast (VNC) images acquired with spectral-detector-CT (SDCT). 142 patients, of which 21 have been treated with amiodarone, receiving SDCT-examinations (unenhanced-chest CT [TNC], CT-angiography of chest and abdomen [CTA-Chest, CTA-Abdomen]) were included. TNC, CTA-Chest, CTA-Abdomen, and corresponding VNC-images (VNC-Chest, VNC-Abdomen) were reconstructed. Liver-attenuation-index (LAI) was calculated as difference between liver- and spleen-attenuation. Liver-attenuation and LAI derived from TNC-images of patients receiving amiodarone were higher. Contrary to TNC, liver-attenuation and LAI were not higher in amiodarone patients in VNC-Chest and in VNC-Abdomen. To verify these initial results, a phantom scan was performed and an additional patient cohort included, both confirming that VNC is viable of accurately subtracting iodine of hepatic amiodarone-deposits. This might help to monitor liver-attenuation more accurately and thereby detect liver steatosis as a sign of liver damage earlier as well as to verify amiodarone accumulation in the liver.

Background: Magnetic resonance (MR) relaxometry is of increasing scientific relevance in neurodegenerative disorders but is still not established in clinical routine. Several studies have investigated relaxation time alterations in disease-specific areas in Parkinson's disease (PD), all using manually drawn regions of interest (ROI). Implementing MR relaxometry into the clinical setting involves the reduction of time needed for postprocessing using an investigator-independent and reliable approach. The aim of this study was to evaluate an automated, atlas-based ROI method for evaluating T2* relaxation times in patients with PD., Method: Automated atlas-based ROI analysis of quantitative T2* maps were generated from 20 PD patients and 20 controls. To test for the accuracy of the atlas-based ROI segmentation, we evaluated the spatial overlap in comparison with manually segmented ROIs using the Dice similarity coefficient (DSC). Additionally, we tested for group differences using our automated atlas-based ROIs of the putamen, globus pallidus, and substantia nigra., Results: A good spatial overlap accuracy was shown for the automated segmented putamen (mean DSC, 0.64 ± 0.04) and was inferior but still acceptable for the substantia nigra (mean DSC, 0.50 ± 0.17). Based on our automated defined ROI selection, a significant decrease of T2* relaxation time was found in the putamen as well as in the internal and external globus pallidus in PD patients compared with healthy controls., Conclusion: Automated digital brain atlas-based approaches are reliable, more objective and time-efficient, and therefore have the potential to replace the time-consuming manual drawing of ROIs.

Retrievable inferior vena cava filters (IVCFs) are known to provide safe and effective pulmonary embolism protection when used appropriately. Long-term complications have been reported over the past 10 years, including vena cava perforation, filter migration, strut fracture, and injury to adjacent structures. This article describes the case of a 44-year-old woman who presented with right ureteral obstruction from strut impingement by a Bard Recovery IVCF (Tempe, AZ, USA). The filter had been in place for 6 years, and the authors were successful in retrieving it using a percutaneous endovascular approach, despite an unexpected chronic right innominate vein occlusion. In addition to highlighting the technical feasibility of long-term retrieval, this case underscores the importance of an IVCF registry to improve retrieval rates. This close monitoring and timely retrieval of filters may help prevent serious long-term complications., (Copyright © 2014 Elsevier Inc. All rights reserved.)