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PURPOSE: To investigate the clinical application of zonally magnified oblique multislice (ZOOM) imaging technology in patients with degenerative cervical myelopathy (DCM) and compare it with T2WI imaging. METHODS: A total of 111 patients diagnosed with DCM were recruited. According to mJOA, patients with DCM were divided into ND + group with neurological dysfunction and ND- group without neurological dysfunction. Routine MRI and ZOOM-DWI were performed on 3.0 T MRI to obtain sagittal T2WI and apparent diffusion coefficient (ADC) diagram. ADC values of the narrow segment and its adjacent upper and lower segments were measured, and compared between the ND + and ND- groups. The correlation between ADC value of cervical spinal cord and mJOA score was analyzed. Additionally, ROC curves were plotted to calculate the AUC values. RESULTS: The comparison between ND + and ND- groups shows that there are significant differences in mJOA score, T2WI, anteroposterior diameter of spinal canal, ADC values of narrow, upper and lower segment (P < 0.05). In ND + group, there is a significant difference between ADC values of the narrow and its upper and lower segments (P < 0.001), while with no significant difference in ADC values of the upper and lower segments (P > 0.05). Results of correlation analysis indicate that in the ND + group, neurological dysfunction evaluated by mJOA scores is correlated with increased ADC values of the narrow segment (r = -0.52, P < 0.001), but not significantly correlated with ADC values of the upper and lower segments. Furthermore, T2WI, anteroposterior diameter of the spinal canal, and cervical cord ADC values all has diagnostic efficacy in evaluating neurological dysfunction in DCM (AUC > 0.5, P < 0.05), with the ADC value of the narrow segment being optimal. CONCLUSION: The ADC value of spinal cord obtained by small-field ZOOM-DWI can be used to evaluate neurological dysfunction in DCM, and is superior to traditional T2WI.

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PURPOSE: Spatiotemporal encoding (SPEN) MRI offers a unique alternative to address image distortion problems in echo planar acquisition-based techniques, at portable low-field systems that lack multiple receiver coils. However, existing 2-π multislice SPEN schemes fail to keep consistent SNRs and contrasts with different numbers of slice settings. This work proposes a new multislice SPEN scheme (SPENms) to achieve stable quality imaging in portable low-field MRI systems. METHODS: The proposed SPENms includes the insertion of one selective π pulse and one non-selective π pulse, closely arranged together, before the frequency-swept π pulse in the original 2D SPEN sequence. Theoretical simulations and experiments on phantoms and human brains were conducted to validate its SNR and contrast performances under different parameters compared to the existing 2-π multislice SPEN scheme. RESULTS: Both simulations and experiments demonstrate the consistent image quality of SPENms with different scanning parameters and targets, as well as good distortion resistance and scan efficiency. Robust diffusion weighted multislice SPEN images of diagnostic value were also highlighted. CONCLUSION: SPENms provides a robust fast echo planar acquisition approach to obtain multislice 2D images with less distortions, consistent SNRs and contrasts at portable low-field MRI systems.

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Transcatheter aortic valve replacement (TAVR) is preferred therapy for elderly patients with severe aortic stenosis (AS) and increasingly used in younger patient populations with good safety and efficacy outcomes. However, cardiac conduction abnormalities remain a frequent complication after TAVR ranging from relative benign interventriculair conduction delays to prognostically relevant left bundle branch block and complete atrio-ventricular (AV) block requiring permanent pacemaker implantation (PPI). Although clinical, procedural and electrocardiographic factors have been identified as predictors of this complication, there is a need for advanced strategies to control the burden of conduction defects particularly as TAVR shifts towards younger populations. This state of the art review highlights the value of ECG-synchronized computed tomographic angiography (CTA) evaluation of the aortic root to better understand and manage conduction problems post-TAVR. An update on CTA derived anatomic features related to conduction issues is provided and complemented with computational framework modelling. This CTA-derived 3-dimensional anatomical reconstruction tool generates patient-specific TAVR simulations enabling operators to adapt procedural strategy and implantation technique to mitigate conduction abnormality risks.

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Background: Simultaneous multislice (SMS) technology improves acquisition efficiency of diffusion-weighted imaging (DWI). This study aimed to evaluate the performance of SMS-DWI in image quality and apparent diffusion coefficient (ADC) measurements for focal liver lesions (FLLs) as compared with that of conventional DWI (CON-DWI). Methods: The institutional ethics committee of West China Hospital, Sichuan University approved this single-center, prospective study conducted from February 2021 to March 2022. Free-breathing SMS-DWI and CON-DWI examinations were acquired on a 3-T scanner with b-values of 50, 400, and 800 s/mm2. Qualitative image quality and quantitative measurements of signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and ADC were compared between SMS-DWI and CON-DWI. The ADC values for FLLs were further compared between SMS-DWI and CON-DWI in different patient subgroups. The intra- and interreader agreements were assessed. Significance was set at P<0.05. Results: This study included 116 patients (96 males, 20 females; mean age 52.0±10.7 years) with 119 FLLs. No significant differences were observed between SMS-DWI and CON-DWI regarding overall image quality in any b-value DWIs, and there were also no differences observed between SMS-DWI and CON-DWI (b=800 s/mm2) for either SNR or CNR (both P values >0.05). ADC values obtained from CON-DWI were higher than those from SMS-DWI in all FLLs [(1.31±0.47)×10-3 vs. (1.26±0.46)×10-3 mm2/s; P=0.004], and similar findings were observed across the different patient subgroups. The consistency analysis showed intrareader intraclass correlation coefficient (ICC) values of 0.792-0.944 and interreader ICC values of 0.758-0.861 for quantitative measurements (SNR, CNR, and ADC) and kappa values of 0.609-0.878 for qualitative image quality. Conclusions: SMS-DWI achieved a 37% reduction in scan time compared to CON-DWI while maintaining comparable overall image quality. Notably, the ADC values for FLLs were observed to be quantitatively lower with SMS-DWI.

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BACKGROUND: Transcatheter mitral valve replacement (TMVR) has emerged as a minimally invasive alternative to mitral valve surgery for patients at high or prohibitive operative risk. Prospective studies reported favourable outcomes in patients with annulus calcification (valve-in-mitral annulus calcification; ViMAC), failed annuloplasty ring (mitral valve-in-ring; MViR), and bioprosthetic mitral valve dysfunction (mitral valve-in-valve; MViV). Multi-slice computed tomography (MSCT)-derived 3D-modelling and simulations may provide complementary anatomical perspectives for TMVR planning. AIMS: We aimed to illustrate the implementation of MSCT-derived modelling and simulations in the workup of TMVR for ViMAC, MViR, and MViV. METHODS: For this retrospective study, we included all consecutive patients screened for TMVR and compared MSCT data, echocardiographic outcomes and clinical outcomes. RESULTS: Sixteen out of 41 patients were treated with TMVR (ViMAC n = 9, MViR n = 3, MViV n = 4). Eleven patients were excluded for inappropriate sizing, 4 for anchoring issues and 10 for an unacceptable risk of left ventricular outflow tract obstruction (LVOTO) based on 3D modelling. There were 3 procedure-related deaths and 1 non-procedure-related cardiovascular death during 30 days of follow-up. LVOTO occurred in 3 ViMAC patients and 1 MViR patient, due to deeper valve implantation than planned in 3 patients, and anterior mitral leaflet displacement with recurrent basal septum thickening in 1 patient. TMVR significantly reduced mitral mean gradients as compared with baseline measurements (median mean gradient 9.5 (9.0-11.5) mm Hg before TMVR versus 5.0 (4.5-6.0) mm Hg after TMVR, p = 0.03). There was no residual mitral regurgitation at 30 days. CONCLUSION: MSCT-derived 3D modelling and simulation provide valuable anatomical insights for TMVR with transcatheter balloon expandable valves in ViMAC, MViR and MViV. Further planning iterations should target the persistent risk for neo-LVOTO.

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Pulmonary arterial hypertension affects females more frequently than males, and there are known sex-related differences in the lungs. However, normal sex-related differences in pulmonary vascular structure remain incompletely described. We aimed to contrast computed tomography-derived pulmonary vascular volume and its distribution within the lungs of healthy adult females and males. From the CanCOLD Study, we retrospectively identified healthy never-smokers. We analyzed full-inspiration computed tomography images, using vessel and airway segmentation to generate pulmonary vessel volume, vessel counts, and airway counts. Vessels were classified by cross-sectional area >10, 5-10, and <5 mm2 into bins, with volume summed within each area bin and in total. We included 46 females and 36 males (62 ± 9 years old). Females had lower total lung volume, total airway counts, total vessel counts, and total vessel volume (117 ± 31 vs. 164 ± 28 mL) versus males (all p < 0.001). Females also had lower vessel volume >10 mm2 (14 ± 8 vs. 27 ± 9 mL), vessel volume 5-10 mm2 (35 ± 11 vs. 55 ± 10 mL), and vessel volume <5 mm2 (68 ± 18 vs. 82 ± 19 mL) (all p < 0.001). Normalized to total vessel volume, vessel volume >10 mm2 (11 ± 4 vs. 16 ± 4%, p < 0.001) and 5-10 mm2 (30 ± 6 vs. 34 ± 5%, p = 0.001) remained lower in females but vessel volume <5 mm2 relative to total volume was 18% higher (59 ± 8 vs. 50 ± 7%, p < 0.001). Among healthy older adults, pulmonary vessel volume is distributed into smaller vessels in females versus males.

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PURPOSE: The aim of this study was to investigate the clinical and multi-slice spiral computed tomography angiography (MSCTA) characteristics for the diagnosis of infected AAA. METHODS: This retrospective comparative study included patients who were diagnosed with AAA at our hospital between January 2014 and May 2023. RESULTS: A total of 40 patients were included, comprising 20 with infected AAA and 20 with non-infected AAA. Patients with infected AAA were more likely to be younger (62.9 ± 10.1 vs. 70.0 ± 4.4 years, P = 0.007) and to present with fever [7 (35%) vs. 1 (5%), P = 0.026], pain [15 (75%) vs. 2 (10%), P < 0.001], higher C-reactive protein levels (60.4 ± 57.0 vs. 4.1 ± 2.9 mg/l, P = 0.005), and higher erythrocyte sedimentation rates (47.7 ± 23.4 vs. 15.2 ± 8.3 mm/h, P < 0.001) compared to those with non-infected AAA. Moreover, those with infected AAA exhibited significantly more eccentric saccular morphology [17 (85%) vs. 1 (5%), P = 0.002], a smaller longitudinal-transverse ratio (1.12 ± 0.33 vs. 2.33 ± 0.54, P = 0.001), thicker peri-aneurysmal soft tissue (2.29 ± 1.48 vs. 0.73 ± 0.55 cm, P < 0.001), more lobulated margins [18 (90%) vs. 1 (5%), P = 0.001], lower aortic calcification scores (49 vs. 56, P < 0.001), more pneumatosis [6 (30%) vs. 0 (0%), P = 0.014], more ruptures [15 (75%) vs. 5 (20%), P = 0.002], more blurred peri-abdominal aortic fat spaces [16 (80%) vs. 2 (10%), P = 0.001], more adjacent bone destruction [5 (25%) vs. 0 (0%), P = 0.025], more involvement of the psoas major muscle [8 (40%) vs. 1 (5%), P = 0.005], more lymphadenectasis [8 (40%) vs. 1 (5%), P = 0.020], and less tortuous aortas [2 (10%) vs. 9 (45%), P = 0.034] compared with those with non-infected AAA. CONCLUSION: The clinical manifestations and MSCTA characteristics may differ between infected and non-infected AAA.

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PURPOSE: Data for QSM are typically acquired using multi-echo 3D gradient echo (GRE), but EPI can be used to accelerate QSM and provide shorter acquisition times. So far, EPI-QSM has been limited to single-echo acquisitions, which, for 3D GRE, are known to be less accurate than multi-echo sequences. Therefore, we compared single-echo and multi-echo EPI-QSM reconstructions across a range of parallel imaging and multiband acceleration factors. METHODS: Using 2D single-shot EPI in the brain, we compared QSM from single-echo and multi-echo acquisitions across combined parallel-imaging and multiband acceleration factors ranging from 2 to 16, with volume pulse TRs from 21.7 to 3.2 s, respectively. For single-echo versus multi-echo reconstructions, we investigated the effect of acceleration factors on regional susceptibility values, temporal noise, and image quality. We introduce a novel masking method based on thresholding the magnitude of the local field gradients to improve brain masking in challenging regions. RESULTS: At 1.6-mm isotropic resolution, high-quality QSM was achieved using multi-echo 2D EPI with a combined acceleration factor of 16 and a TR of 3.2 s, which enables functional applications. With these high acceleration factors, single-echo reconstructions are inaccurate and artefacted, rendering them unusable. Multi-echo acquisitions greatly improve QSM quality, particularly at higher acceleration factors, provide more consistent regional susceptibility values across acceleration factors, and decrease temporal noise compared with single-echo QSM reconstructions. CONCLUSION: Multi-echo acquisition is more robust for EPI-QSM across parallel imaging and multiband acceleration factors than single-echo acquisition. Multi-echo EPI can be used for highly accelerated acquisition while preserving QSM accuracy and quality relative to gold-standard 3D-GRE QSM.

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THE STUDY OBJECTIVE: Was to assess the qualitative and quantitative characteristics of the bone regenerate in the distant period following compression-distraction osteosynthesis. MATERIAL AND METHODS: Results from the treatment of 30 patients with mandibular micrognathia, were analyzed. Compression-distraction osteosynthesis (CDO) was performed in the area of the mandibular angle. The patients were divided into two groups: group 1 consisted of 16 patients with congenital micrognathia, and group 2 comprised 14 patients with acquired (post-traumatic) micrognathia. For the assessment of qualitative and quantitative characteristics of the bone regenerate, three-dimensional modeling, morphometric measurements of the regenerate, and evaluation of bone density using the Hounsfield scale through multislice computed tomography were used. RESULTS AND DISCUSSION: The study of the bone regenerate parameters in group 1 yielded the following results: the length of the bone regenerate decreased by 2.14%; the thickness of the bone regenerate increased by 8.75%; the height of the bone regenerate increased by 1.75%. In group 2, the values were 3.14; 3 and 3.76%, correspondingly. In patients of group 1, the length of the mandibular branch increased by 4%; the length of the mandibular body increased by 5.35%. In group 2, the length of the mandibular branch increased by 1.94%; the length of the mandibular body increased by 2.2%. The density of the cortical bone of the regenerate corresponds to the density of the intact bone, while the density of the cancellous bone is slightly reduced. CONCLUSION: Qualitative and quantitative characteristics of bone regenerate in the long-term period after CDO correspond to the parameters of intact bone. CDO can be considered not only as a preparatory stage for reconstructive operations after the growth of the skull bones has completed, but also as an independent stage of treatment.

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BACKGROUND: In deep inferior epigastric artery (DIEA) perforator (DIEP) flap breast reconstruction, the network with the superficial inferior epigastric artery (SIEA) is key to achieving stable subcutaneous blood flow to the flap. This study investigated how the diameter and location of the DIEA perforator affect continuity with the SIEA. METHODS: A retrospective analysis of 94 specimens from 47 patients who underwent DIEA perforator flap breast reconstruction was performed. Relationships between the diameter and location of the DIEA perforator and its continuity with the SIEA were examined on preoperative multi-slice computed tomography. RESULTS: The largest DIEA perforator on each specimen showed continuity with the SIEA in 94 %, significantly more than the second (80 %; p = 0.027) or third largest perforator (76 %; p = 0.005). Medial perforators from 3 cm above to 3 cm below the umbilicus showed more continuity with the SIEA than lateral perforators (p = 0.008). CONCLUSIONS: Selection of the largest perforator of DIEP flap is advantageous in terms of continuity with the SIEA. Also, near the umbilicus, medial perforators communicate with the SIEA more than lateral perforators.

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Background: Simultaneous multi-slice (SMS) bSSFP imaging enables stress myocardial perfusion imaging with high spatial resolution and increased spatial coverage. Standard parallel imaging techniques (e.g., TGRAPPA) can be used for image reconstruction but result in high noise level. Alternatively, iterative reconstruction techniques based on temporal regularization (ITER) improve image quality but are associated with reduced temporal signal fidelity and long computation time limiting their online use. The aim is to develop an image reconstruction technique for SMS-bSSFP myocardial perfusion imaging combining parallel imaging and image-based denoising using a novel noise map estimation network (NoiseMapNet), which preserves both sharpness and temporal signal profiles and that has low computational cost. Methods: The proposed reconstruction of SMS images consists of a standard temporal parallel imaging reconstruction (TGRAPPA) with motion correction (MOCO) followed by image denoising using NoiseMapNet. NoiseMapNet is a deep learning network based on a 2D Unet architecture and aims to predict a noise map from an input noisy image, which is then subtracted from the noisy image to generate the denoised image. This approach was evaluated in 17 patients who underwent stress perfusion imaging using a SMS-bSSFP sequence. Images were reconstructed with (a) TGRAPPA with MOCO (thereafter referred to as TGRAPPA), (b) iterative reconstruction with integrated motion compensation (ITER), and (c) proposed NoiseMapNet-based reconstruction. Normalized mean squared error (NMSE) with respect to TGRAPPA, myocardial sharpness, image quality, perceived SNR (pSNR), and number of diagnostic segments were evaluated. Results: NMSE of NoiseMapNet was lower than using ITER for both myocardium (0.045 ± 0.021 vs. 0.172 ± 0.041, p < 0.001) and left ventricular blood pool (0.025 ± 0.014 vs. 0.069 ± 0.020, p < 0.001). There were no significant differences between all methods for myocardial sharpness (p = 0.77) and number of diagnostic segments (p = 0.36). ITER led to higher image quality than NoiseMapNet/TGRAPPA (2.7 ± 0.4 vs. 1.8 ± 0.4/1.3 ± 0.6, p < 0.001) and higher pSNR than NoiseMapNet/TGRAPPA (3.0 ± 0.0 vs. 2.0 ± 0.0/1.3 ± 0.6, p < 0.001). Importantly, NoiseMapNet yielded higher pSNR (p < 0.001) and image quality (p < 0.008) than TGRAPPA. Computation time of NoiseMapNet was only 20s for one entire dataset. Conclusion: NoiseMapNet-based reconstruction enables fast SMS image reconstruction for stress myocardial perfusion imaging while preserving sharpness and temporal signal profiles.

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PURPOSE: To establish an interleaved multislice variant of the averaged magnetization inversion-recovery acquisitions (AMIRA) approach for 2D spinal cord imaging with increased acquisition efficiency compared with the conventional 2D single-slice approach(es), and to determine essential prerequisites for a working interleaved multislice AMIRA approach in practice. METHODS: The general AMIRA concept is based on an inversion recovery-prepared, segmented, and time-limited cine balanced SSFP sequence, generating images of different contrast. For AMIRA imaging of multiple, independent slices in a 2D interleaved fashion, a slice loop within the acquisition loops was programmed. The former non-selective inversions were replaced with slice-selective inversions with user-definable slice thickness. RESULTS: The thickness of the slice-selective inversion in 2D interleaved multislice AMIRA should be doubled compared with the manufacturer's standard setting to avoid an increased sensitivity to flow and pulsation effects particularly in the CSF. However, this solution also limits its practical applicability, as slices located at directly adjacent vertebrae cannot be imaged together. Successful interleaved two-slice AMIRA imaging for a "reference" in vivo protocol with 0.50 × 0.50 mm2 in-plane resolution and 8-mm slice thickness is demonstrated, therefore halving its acquisition time per slice from 3 min down to 1.5 min. CONCLUSION: The investigated 2D interleaved two-slice AMIRA variant facilitates spinal cord imaging that maintains similar contrast and the same resolution as the conventional 2D single-slice AMIRA approach, but does so with a halved acquisition time.

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Introduction: Use of functional MRI in awake non-human primate (NHPs) has recently increased. Scanning animals while awake makes data collection possible in the absence of anesthetic modulation and with an extended range of possible experimental designs. Robust awake NHP imaging however is challenging due to the strong artifacts caused by time-varying off-resonance changes introduced by the animal's body motion. In this study, we sought to thoroughly investigate the effect of a newly proposed dynamic off-resonance correction method on brain activation estimates using extended awake NHP data. Methods: We correct for dynamic B0 changes in reconstruction of highly accelerated simultaneous multi-slice EPI acquisitions by estimating and correcting for dynamic field perturbations. Functional MRI data were collected in four male rhesus monkeys performing a decision-making task in the scanner, and analyses of improvements in sensitivity and reliability were performed compared to conventional image reconstruction. Results: Applying the correction resulted in reduced bias and improved temporal stability in the reconstructed time-series data. We found increased sensitivity to functional activation at the individual and group levels, as well as improved reliability of statistical parameter estimates. Conclusions: Our results show significant improvements in image fidelity using our proposed correction strategy, as well as greatly enhanced and more reliable activation estimates in GLM analyses.

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BACKGROUND: This study explores the diagnostic value of combining fractional-order calculus (FROC) diffusion-weighted model with simultaneous multi-slice (SMS) acceleration technology in distinguishing benign and malignant breast lesions. METHODS: 178 lesions (73 benign, 105 malignant) underwent magnetic resonance imaging with diffusion-weighted imaging using multiple b-values (14 b-values, highest 3000 s/mm2). Independent samples t-test or Mann-Whitney U test compared image quality scores, FROC model parameters (D,, ), and ADC values between two groups. Multivariate logistic regression analysis identified independent variables and constructed nomograms. Model discrimination ability was assessed with receiver operating characteristic (ROC) curve and calibration chart. Spearman correlation analysis and Bland-Altman plot evaluated parameter correlation and consistency. RESULTS: Malignant lesions exhibited lower D, and ADC values than benign lesions (P < 0.05), with higher values (P < 0.05). In SSEPI-DWI and SMS-SSEPI-DWI sequences, the AUC and diagnostic accuracy of D value are maximal, with D value demonstrating the highest diagnostic sensitivity, while value exhibits the highest specificity. The D and combined model had the highest AUC and accuracy. D and ADC values showed high correlation between sequences, and moderate. Bland-Altman plot demonstrated unbiased parameter values. CONCLUSION: SMS-SSEPI-DWI FROC model provides good image quality and lesion characteristic values within an acceptable time. It shows consistent diagnostic performance compared to SSEPI-DWI, particularly in D and values, and significantly reduces scanning time.

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Transcatheter aortic valve implantation (TAVI) has established as a gold standard in the treatment of elderly patients with severe aortic stenosis. Vascular access marks the first step in a TAVI procedure where the transfemoral access is preferred. Therefore, vascular complications are one of the main concerns of operators. With the increasing number of TAVIs performed, the focus is on the prevention and management of vascular complications. Illustrated by a clinical case, this article attempts to review the main vascular complications, their management and how to prevent them.

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Background: Thoracolumbar vertebral fractures are common pathological fractures caused by osteoporosis in the elderly. These fractures are challenging to detect. This study aimed to evaluate the diagnostic value of Hounsfield units for osteoporotic thoracolumbar vertebral non-compression fractures in elderly patients with low-energy fractures. Methods: The retrospective case-control study included elderly patients diagnosed with osteoporotic thoracolumbar vertebral fractures and non-fractured patients who underwent computed tomography examinations for lumbar vertebra issues during July 2017 and June 2020. Results: This study included 216 patients with fractures (38 males and 178 females; average age: 77.28±8.68 years) and 124 patients without fractures (21 males and 103 females; average age: 75.35±9.57 years). The difference in Hounsfield units of the target (intermediate) vertebral body significantly differed between the two groups (54.74 ± 21.84 vs 5.86 ± 5.14; p<0.001). The ratios of Hounsfield units were also significantly different between the two groups (1.38 ± 1.60 vs 0.13 ± 0.23; p<0.001). The cut-off value for the difference in Hounsfield units to detect osteoporotic spine fractures was 25.35, with high sensitivity (98.5%), specificity (99.9%), and the area under the curve (AUC) (0.999, 95% CI: 0.999-1). The cut-off value for the odds ratio of Hounsfield units was 0.260, with high sensitivity (99.1%), specificity (92.7%), and AUC (0.970, 95% CI: 0.949-0.992). Conclusion: The difference between Hounsfield units and the odds ratio of Hounsfield units might help diagnose osteoporotic thoracolumbar vertebral non-compression fractures in elderly patients with low-energy fractures.

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Objective: The diagnostic value of multi-slice computed tomography (MSCT) in esophageal jujube pit impaction was explored in this study. Methods: A retrospective analysis was performed on MSCT data obtained from a cohort of 40 patients experiencing esophageal jujube pit impaction. The study period encompassed the interval from December 2018 to November 2019. The analysis involved examining the age distribution of the patients, the location of the jujube pit impaction, its connection to the esophagus, associated complications, and the methods used for treatment. All imaging results were compared with the outcomes of surgical or endoscopic interventions. Results: (1) Out of 40 patients, 30 individuals were 58 years old or above, constituting 75% of the study sample. (2) In 80% of the instances (32 cases), the jujube pit was located in the initial segment of the esophagus, exhibiting a spindle shape with varying levels of central low density. (3) We examined the correlation between the angle of the impacted jujube pit and the esophageal longitudinal axis, categorizing 2 cases as longitudinal impaction, 16 as oblique impaction, and 22 as transverse impaction. Among the 40 cases, 28 displayed only slight thickening of the esophageal wall at the impaction site, while 9 cases exhibited heightened periesophageal fat density, and 3 showed small periesophageal air bubbles. (4) Endoscopic evaluation identified damage to the esophageal mucosa in 35 instances and the formation of esophageal perforation in 5 cases. Among patients with perforation, one or both ends of the jujube pit had penetrated the esophageal wall, accompanied by different levels of surrounding inflammatory encapsulation. Conclusion: MSCT is crucial for pinpointing jujube pit impaction and its relation to the esophageal wall and nearby structures, aiding in preoperative and postoperative complications. It is highly feasible for endoscopic cases but limited in complex ones needing thoracoscopy or open-heart surgery.

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For cryo-electron tomography (cryo-ET) of beam-sensitive biological specimens, a planar sample geometry is typically used. As the sample is tilted, the effective thickness of the sample along the direction of the electron beam increases and the signal-to-noise ratio concomitantly decreases, limiting the transfer of information at high tilt angles. In addition, the tilt range where data can be collected is limited by a combination of various sample-environment constraints, including the limited space in the objective lens pole piece and the possible use of fixed conductive braids to cool the specimen. Consequently, most tilt series are limited to a maximum of ±70°, leading to the presence of a missing wedge in Fourier space. The acquisition of cryo-ET data without a missing wedge, for example using a cylindrical sample geometry, is hence attractive for volumetric analysis of low-symmetry structures such as organelles or vesicles, lysis events, pore formation or filaments for which the missing information cannot be compensated by averaging techniques. Irrespective of the geometry, electron-beam damage to the specimen is an issue and the first images acquired will transfer more high-resolution information than those acquired last. There is also an inherent trade-off between higher sampling in Fourier space and avoiding beam damage to the sample. Finally, the necessity of using a sufficient electron fluence to align the tilt images means that this fluence needs to be fractionated across a small number of images; therefore, the order of data acquisition is also a factor to consider. Here, an n-helix tilt scheme is described and simulated which uses overlapping and interleaved tilt series to maximize the use of a pillar geometry, allowing the entire pillar volume to be reconstructed as a single unit. Three related tilt schemes are also evaluated that extend the continuous and classic dose-symmetric tilt schemes for cryo-ET to pillar samples to enable the collection of isotropic information across all spatial frequencies. A fourfold dose-symmetric scheme is proposed which provides a practical compromise between uniform information transfer and complexity of data acquisition.

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BACKGROUND: Semi-automated software is essential for planning and prosthesis selection prior transcatheter aortic valve replacement (TAVR). Reliable data on the usability of software programs for planning a TAVR is missing. The aim of this study was to compare software programs 'Valve Assist 2' (GE Healthcare) and 3mensio 'Structural Heart' (Pie Medical Imaging) regarding usability and accuracy of prosthesis size selection in program-inexperienced users. METHODS: Thirty-one participants (n = 31) were recruited and divided into program-inexperienced users (beginners) (n = 22) and experts (n = 9). After software training, beginners evaluated 3 patient cases in 129 measurements (n = 129) using either Valve Assist 2 (n = 11) or Structural Heart (n = 11) on 2 test days (T1, T2). System Usability Scale (SUS) and ISONORM 9241/110-S (ISONORM) questionnaire were used after the test. The valve size selected by each beginner was compared with the valve size selected from expert group. RESULTS: Valve Assist 2 had higher SUS Score: median 78.75 (25th, 75th percentile: 67.50, 85.00) compared to Structural Heart: median 65.00 (25th, 75th percentile: 47.50, 73.75), (p < 0,001, r = 0.557). Also, Valve Assist 2 showed a higher ISONORM score: median 1.05 (25th, 75th percentile: - 0.19, 1.71) compared to Structural Heart with a median 0.05 (25th, 75th percentile: - 0.49, 0.13), (p = 0.036, r = 0.454). Correctly selected valve sizes were stable over time using Valve Assist 2: 72.73% to 69.70% compared to Structural Heart program: 93.94% to 40% (χ2 (1) = 21.10, p < 0.001, φ = 0.579). CONCLUSION: The study shows significant better usability scores for Valve Assist 2 compared to 3mensio Structural Heart in program-inexperienced users.