Computed Tomography Analysis Research Articles

Cone-Beam Computed Tomography Analysis of the Root Canal Morphology of Lower Second Molars in the Croatian Subpopulation

The aim of this study was to investigate the root canal morphology of lower second molars in the Croatian subpopulation of the Zagreb region using cone-beam computed tomography (CBCT). We analyzed 3212 CBCT scans from the two radiology centers in Zagreb. The number of roots and root canals, the occurrence of C-shaped canals and additional roots were recorded. “C”-shaped roots were classified according to Melton classification. Canals in the mesial root were classified according to Vertucci. Lower second molars were found on 608 CBCT scans from a total number of 859. Among them, 78 (9.1%) had a “C”-shaped form. In the mesial roots, the frequencies of Vertucci types were: Type I in ninety-four cases (12.0%), Type II in three hundred and twenty cases (41.0%), Type III in six cases (0.8%), Type IV in three hundred and fifty-two cases (45.1%), Type V in three cases (0.4%), Type VI was found in four cases (0.5%) and Type VIII was found in one case (0.1%). Radix entomolaris and paramolaris were found in 29 (3.4%) lower second molars. The lower second molars in the Zagreb population show significant diversity in internal anatomy with a relatively high prevalence of “C”-shaped root canals and merged root canals in the mesial root.

Artificial intelligence-based analysis of the spatial distribution of abnormal computed tomography patterns in SARS-CoV-2 pneumonia: association with disease severity

BackgroundThe substantial heterogeneity of clinical presentations in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia still requires robust chest computed tomography analysis to identify high-risk patients. While extension of ground-glass opacity and consolidation from peripheral to central lung fields on chest computed tomography (CT) might be associated with severely ill conditions, quantification of the central-peripheral distribution of ground glass opacity and consolidation in assessments of SARS-CoV-2 pneumonia remains unestablished. This study aimed to examine whether the central-peripheral distributions of ground glass opacity and consolidation were associated with severe outcomes in patients with SARS-CoV-2 pneumonia independent of the whole-lung extents of these abnormal shadows.MethodsThis multicenter retrospective cohort included hospitalized patients with SARS-CoV-2 pneumonia between January 2020 and August 2021. An artificial intelligence-based image analysis technology was used to segment abnormal shadows, including ground glass opacity and consolidation. The area ratio of ground glass opacity and consolidation to the whole lung (GGO%, CON%) and the ratio of ground glass opacity and consolidation areas in the central lungs to those in the peripheral lungs (GGO(C/P)) and (CON(C/P)) were automatically calculated. Severe outcome was defined as in-hospital death or requirement for endotracheal intubation.ResultsOf 512 enrolled patients, the severe outcome was observed in 77 patients. GGO% and CON% were higher in patients with severe outcomes than in those without. Multivariable logistic models showed that GGO(C/P), but not CON(C/P), was associated with the severe outcome independent of age, sex, comorbidities, GGO%, and CON%.ConclusionIn addition to GGO% and CON% in the whole lung, the higher the ratio of ground glass opacity in the central regions to that in the peripheral regions was, the more severe the outcomes in patients with SARS-CoV-2 pneumonia were. The proposed method might be useful to reproducibly quantify the extension of ground glass opacity from peripheral to central lungs and to estimate prognosis.

Individual age determination based on computed tomography knee analysis using artificial neural networks and computer vision: Preliminary results

BACKGROUND: Currently, studies have focused on the modernization of existing methods of forensic age assessment (bone and skeletal) through the active use of modern methods of medical imaging (e.g., computed tomography) and artificial intelligence for their analysis. This approach enables the creation of new methods for assessing biological age, which is characterized by increased accuracy and reproducibility.
 AIM: To develop and test an algorithm for predicting the biological age of an individual based on computed tomography analysis of the knee joint using artificial neural networks and computer vision.
 MATERIALS AND METHODS: This observational retrospective transverse (one time) study analyzed computed tomography scans (334) of the knee joint performed in the Departments of Radiation Diagnostics of the Priorov Central Institute for Trauma and Orthopedics, Vreden National Medical Center for Traumatology and Orthopedics, between 2018 and 2021. The study enrolled persons of both sexes aged 13–45 years. Cases of developmental abnormalities, knee injuries, signs of general connective tissue pathology were excluded. Research methods include the use of intelligent information technologies (a formalized set of mathematical and software solutions).
 RESULTS: Based on the experiments conducted, an algorithm for assessing age according to the computed tomography scans of the knee joint has been developed. The main components of the developed system are as follows: a preprocessing module, an intelligent computing core, a data analysis module, a three-dimensional reconstruction module, a property extraction module, and a final age assessment module. The essence of the proposed method is the simultaneous use of artificial neural networks and clearly formalized mathematical procedures for calculating the properties of the epiphyseal line. To obtain the results and conduct primary experimental studies that confirmed the feasibility, correctness, and operability of the method, software using the YOLOv5 neural network was developed. The result of the error matrix analysis after training shows a probability of correct recognition of the order of 80%. Verification of experimental studies was performed on 46 cases. At present, the age estimation error is approximately 1 year for children and adolescents.
 CONCLUSIONS: The experimental results have confirmed the adequacy of the age estimates obtained to the actual age of the individual and, consequently, the applicability of the proposed method in forensic medical institutions. The proposed method is currently implemented as a set of software components with subsequent manual integration of automatically calculated data. The plan was to supplement the database of computed tomography images to increase the training sample and the accuracy of age prediction.

LiOH Decomposition by NiO/ZrO2 in Li-Air Battery: Chemical Imaging with Operando Synchrotron Diffraction and Correlative Neutron/X-Ray Computed-Tomography Analysis.

Li-air batteries attract significant attention due to their highest theoretical energy density among all existing energy storage technologies. Currently, challenges related to extending lifetime and long-term stability limit their practical application. To overcome these issues and enhance the total capacity of Li-air batteries, this study introduces an innovative approach with NiO/ZrO2 catalysts. Operando advanced chemical imaging with micrometer spatial resolution unveils that NiO/ZrO2 catalysts substantially change the kinetics of crystalline lithium hydroxide (LiOH) formation and facilitate its rapid decomposition with heterogeneous distribution. Moreover, ex situ combined neutron and X-ray computed tomography (CT) analysis, provide evidence of distinct lithium phases homogeneously distributed in the presence of NiO/ZrO2. These findings underscore the material's superior physico-chemical and electronic properties, with more efficient oxygen diffusion and indications of lower obstruction to its active sites, avoiding clogging in the active electrode, a common cause of capacity loss. Electrochemical tests conducted at high current density demonstrated a significant kinetic enhancement of the oxygen reduction and evolution reactions, resulting in improved charge and discharge processes with low overpotential. This pioneering approach using NiO/ZrO2 catalysts represents a step toward on developing the full potential of Li-air batteries as high-energy-density energy storage systems.

Distal Radius Allograft for Glenohumeral Instability: A Novel Osteochondral Allograft Reconstruction Option in the Setting of Glenoid Bone Loss

Background: Distal tibial allograft (DTA) reconstruction for glenoid bone loss is nonanatomic, as it does not match the glenoid radius of curvature (ROC) in the anterior-posterior (AP) plane. The dorsal articular portion of the distal radius has not been previously described as an allograft reconstruction option for glenoid bone loss. Purpose: To evaluate distal radius fresh-frozen allograft (DRA) as a potential match for glenoid reconstruction. Study Design: Controlled laboratory study. Methods: Eighteen fresh-frozen human cadaveric specimens—including 6 shoulder, 6 wrist, and 6 tibia specimens—were used. The ROC and the graft length were measured in the superior-inferior (SI) plane. A 30% defect was created in all glenoid specimens, and both DTAs and DRAs were harvested to assess graft fit after fixation. Computed tomography analysis was used to assess bony ROC and bone mineral density (BMD). Results: The cadaveric specimens had a mean age of 77 years. The mean SI glenoid length was 39.7 mm compared with 36.8 mm for the DRA and 30 mm for the DTA. The ROC in the SI plane was 29 ± 5.3 mm for the glenoid, 37.8 ± 4.9 mm for the DRA, and 24 ± 3.7 mm for the DTA. In the AP plane, the ROC was 39.6 ± 6.6 mm for the glenoid, 30.4 ± 18.6 mm for the DRA, and 126.3 ± 9.5 mm for the DTA. On computed tomography analysis, the ROC in the SI plane was 30.4 ± 1.5 mm for the glenoid, 30.3 ± 5.6 mm for the DRA, and 24.5 ± 9.4 mm for the DTA. In the AP plane, the ROC was 30.8 ± 2 mm for the glenoid, 19.1 ± 2.3 mm for the DRA, and 46.7 ± 21.7 mm for the DTA. The BMD was 226.3 ± 79 Hounsfield units (HU) for the glenoid, 228.5 ± 94.7 HU for the DRA, 235 ± 96.2 HU for the coracoid process, and 235.1 ± 84.6 HU for the DTA. Conclusion: Compared with the DTA, the DRA had a greater mean graft length in the SI plane, providing utilization in cases of larger bony defects; the DRA has a more acute ROC in the AP plane (closer to that of the glenoid), providing a greater potential buttress to anterior humeral translation. Compared with currently utilized grafts, the DRA BMD was not significantly diminished. This study presents the DRA as a novel allograft reconstruction option in the setting of anterior glenoid bone loss; further biomechanical and clinical investigation is indicated.

Impact of Peroxisome Proliferator-Activated Receptor Agonists on Myosteatosis in the Context of Metabolic Dysfunction-Associated Steatotic Liver Disease.

Metabolic dysfunction-associated steatotic liver disease (MASLD), and more specifically steatohepatitis may be associated with fat infiltration of skeletal muscles which is known as myosteatosis. Pan-peroxisome proliferator-activated receptor (PPAR) agonists have been shown to promote metabolic dysfunction-associated steatohepatitis (MASH) remission. However, the effect of PPAR agonists on myosteatosis remains to be determined. The aim of this review is to evaluate the effect that PPAR agonists alone or in combination, have on myosteatosis in the context of MASLD. Original research reports concerning the impact of PPAR agonists on muscle fat in MASLD were screened from PUBMED and EMBASE databases following the PRISMA methodology. Eleven original manuscripts were included in this review. Two preclinical studies assessed the impact of the PPARα agonist on fat content in the quadriceps muscle and the liver by extracting triglycerides in rats fed a high-fat diet and in insulin-resistant mice. Both models showed muscle and liver triglyceride content reduction using WY14643. Fenofibrate had no significant impact on soleus intramyocellular lipids or liver fat content in insulin-resistant subjects based on proton magnetic resonance spectroscopy. Treatment with PPARδ agonists increased the expression of genes involved in fatty acid oxidation in two studies on muscle cell culture. PPARγ agonists were investigated in two preclinical studies and one clinical study using spectroscopy and computed tomography respectively. In the first preclinical study in Zucker diabetic fatty rats, rosiglitazone reduced muscle lipids and hepatic steatosis. In a second preclinical study using the same animal model, pioglitazone reduced tibialis anterior intramyocellular lipids. In contrast, computed tomography analyses in patients with type 2 diabetes revealed a surface area increase of low-density muscles (suggesting an increase in muscle fat content) after a one-year treatment with rosiglitazone. Varying combinations of PPAR agonists (cevoglitazar, fenofibrate/pioglitazone and muraglitazar) were evaluated in two preclinical studies and one clinical study. In rats, these treatments showed variable results for muscle and liver depending on the combinations studied. In type 2 diabetic patients, treatment with muraglitazar (a PPARα/γ agonist) reduced the intramyocellular lipid content of tibialis anterior as well as liver fat content following spectroscopy assessment. The combination of different PPAR agonists could have a positive impact on reducing myosteatosis, in addition to their effect on the liver. Some discrepancies could be explained by the different techniques used to assess muscle lipid content, the muscles assessed and the possible adipogenic effect of PPARγ agonists. Further clinical research is needed to fully assess the efficacy of these treatments on both MASLD progression and associated myosteatosis.

Influence of Different Glide Path Techniques on Microcrack Formation after Two Different Root Canal Preparation Treatments: Micro Computed Tomography Analysis.

This study aimed to evaluate the effect of WaveOne Glider (WOGG) with Waveone Gold (WOG) primary reciprocation systems on root dentine microcrack formation and to know the effect of TruNatomy Glider (TRNG) with TruNatomy (TRN) prime rotary systems on root dentine microcrack formation. In this study, 40 extracted mandibular first molar roots were selected and divided randomly into four groups (n=10). Group MWOG: a manual glide path was performed + WOG primary. Group MTRN: manual glide path performed+TRN prime. Additionally, group WOGG: glide path preparation with WOGG+WOG primary. Finally, for group TRNG, the glide path preparation was performed with TRNG+TRN prime. Micro-CT was used for pre and post-instrumentation image analysis. Statistical analysis was performed using the Kruskal- Wallis test (p<0.05) with Two-way ANOVA. The Kruskal-Wallis test showed no significant differences among all groups in all thirds for pre and post-instrumentation regarding the crack formation. The Two-way ANOVA showed no significant difference or interaction between the ways of glide path preparation, whether manual or reciprocal WOGG, or between the rotary TRNG and the motion used in root canal preparation (rotary TRN or reciprocal WOG) regarding the crack formation and propagation. Microcrack formation and propagation occurred independently of using different glide path techniques (manual, rotary, or reciprocal).

A Quantitative Computed Tomography Analysis of Fissure Integrity and Emphysema Destruction in Japanese Patients with Severe Chronic Obstructive Pulmonary Disease.

Objective Bronchoscopic lung volume reduction (BLVR) using a one-way endobronchial valve (EBV) can provide clinically meaningful benefits to chronic obstructive pulmonary disease (COPD) patients. Although the Japanese Pharmaceuticals and Medical Devices Agency approved EBVs in November 2022, information regarding the number of Japanese patients with severe COPD eligible for BLVR treatment is still lacking. We therefore screened computed tomography (CT) images of patients with severe COPD using a quantitative CT (QCT) analysis to estimate the proportion of candidates eligible for BLVR treatment with an EBV. Methods CT scans of COPD patients with Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages 3 and 4 were retrospectively analyzed using QCT to evaluate fissure integrity and tissue destruction. The difference in volume-weighted percentage was measured using the density scores of the target lobe and ipsilateral non-target lobe at -910 Hounsfield units. The target lobe was defined as the most affected lobe, with an emphysema destruction score of >50% for each patient. Results High-resolution CT scans of 32 patients (GOLD 3=19, GOLD 4=13) were analyzed. The target lobe could not be identified in 1 patient, whereas the target lobes for 8 patients were not surrounded by fissures with ≥80% completeness. Conversely, in 13 patients, the target lobes were surrounded by fissures with >95% completeness. The remaining 10 patients had fissure completeness between 80% and 95% at the target lobes and were considered candidates for collateral ventilation assessment. Conclusion A QCT analysis showed that 23 of 32 patients with severe COPD could be considered for a thorough examination of BLVR treatment with EBV.

A statistical approach for characterizing the compressive stress of foams via computed tomography

The compressive stress of foams is of significant interest to manufacturers: It directly affects if a foam is suited for a specific use case or not. Therefore, achieving exact outcomes in production is crucial. Computed tomography (CT) is a destruction free imaging process which is increas-ingly utilized in metrology to analyze the internal structure of industrial materials, for example their porosity. Subject of this paper is to find a link between pore parameters as well as their distribution in the foam and the compressive stress of the entire foam structure by using CT analysis and statistical methods.

Are clinically unimportant findings qualified as benign in lumbar spine imaging reports? A content analysis of plain X-ray, CT and MRI reports.

Lumbar spine diagnostic imaging reports may cause patient and clinician concern when clinically unimportant findings are not explicitly described as benign. Our primary aim was to determine the frequency that common, benign findings are reported in lumbar spine plain X-ray, computed tomography (CT) and magnetic resonance imaging (MRI) reports as either normal for age or likely clinically unimportant. We obtained 600 random de-identified adult lumbar spine imaging reports (200 X-ray, 200 CT and 200 MRI) from a large radiology provider. Only reports requested for low back pain were included. From the report text, one author extracted each finding (e.g., 'broad-based posterior disc bulge') and whether it was present or absent (e.g., no disc bulge) until data saturation was reached, pre-defined as a minimum of 50 reports and no new/similar findings in the last ten reports within each imaging modality. Two authors independently judged whether each finding was likely clinically unimportant or important. For each likely clinicially unimportant finding they also determined if it had been explicitly reported to be benign (expressed as normal, normal for age, benign, clinically unimportant or non-significant). Data saturation was reached after coding 262 reports (80 X-ray, 82 CT, 100 MRI). Across all reports we extracted 3,598 findings. Nearly all reports included at least one clinically unimportant finding (76/80 (95%) X-ray, 80/82 (98%) CT, 99/100 (99%) MRI). Over half of the findings (n = 2,062, 57%; 272 X-Ray, 667 CT, 1123 MRI) were judged likely clinically unimportant. Most likely clinically unimportant findings (90%, n = 1,854) were reported to be present on imaging (rather than absent) and of those only 18% (n = 331) (89 (35%) X-ray, 93 (16%) CT and 149 (15%) MRI) were explicitly reported as benign. Lumbar spine imaging reports frequently include findings unlikely to be clinically important without explicitly qualifying that they are benign.

Three-dimensional computed tomography analysis of the mitral annulus for mitral annuloplasty in 100 cases of robotic mitral valve repair.

This study aimed to evaluate the efficacy of preoperative computed tomography in assessing mitral annulus anatomy and the posterior annular plication rate in mitral valve repair with annuloplasty. From July 2018 to August 2023, we performed robotic mitral valve repair with ring annuloplasty using a semi-rigid ring in 100 patients. Preoperative anatomical assessment of the mitral annulus was conducted by three-dimensional computed tomography. The ring size was selected based on the perioperative commissure-to-commissure length or the anterior leaflet area. The mean commissure-to-commissure length, posterior mitral annular length, and minimum distance between the left circumflex artery and mitral annulus values were 31, 109, and 3.8 mm, respectively. No postoperative left circumflex artery injury or ring detachment was recorded. The mean plication rate (length of the posterior side of the prosthetic ring/posterior annular length) was 0.68, and it did not differ among each prosthetic ring size. The posterior plication rate (duplicate ring size 19.4) was a factor influencing the postoperative transmitral mean pressure gradient of 5 mmHg or higher. Freedom from moderate or severe mitral regurgitation was not different between the two groups above and below the posterior plication rate × ring size of 19.4 (p = 0.73), with an event-free rate of 97% vs. 96% in 3 years, respectively. Preoperative evaluation of the mitral annular anatomy is useful for safe mitral valve repair with ring annuloplasty. Determining ring size by focusing on the posterior annular plication rate may be a new method for ring size selection.

Association between periapical odontogenic lesions and maxillary sinus mucosal thickening: A retrospective computed tomography analysis

Introduction: The maxillary sinuses are located in the middle of the nasal cavity and are thought to have the greatest air gaps. Cone-beam computed tomography (CBCT) imaging was used to characterize the radiographic connection between the apices of posterior maxillary teeth and the floor of the maxillary sinus. This study aims to evaluate the degree of apical periodontitis and the sinus mucosal thickness and find the associations between the patient’s age and gender and the degree of apical periodontitis with sinus mucosal thickness. Materials and Methods: A retrospective analysis of 364 individuals with maxillary sinuses which appears clearly within limited-field CBCT images was performed. It was also categorized and noted how the maxillary sinus floor related to the root tips and periapical lesions. In addition, the patient’s age gender, side, and level of apical periodontitis in relation to maxillary sinus mucosal (MSM) thickness were evaluated. Results: The MSM class and periapical index (PAI) were statistically significantly correlated (P 0.001). In comparison to respondents with PAI score I, respondents with PAI score V had 47.89 times the odds of having a higher MSM class (odds ratio [OR] =47.89, P = 0.05). Age and MSM thickening were not substantially correlated (P = 0.298), whereas gender and MSM thickening were strongly correlated (OR = 1.56, P = 0.05). Conclusions: The result of this study showed a clear association between the periapical lesions and MSM thickening.

Relationship between the impacted mandibular third molar and adjacent second molar' external root resorption by cone-bean computed tomography analysis.

The relationship between the impacted mandibular third molar (IMTM) and the external root resorption (ERR) of the mandibular second molar (MSM) was analysed with cone-beam computed tomography (CBCT). The risk factors affecting the ERR of the MSM were examined to provide a reference. A total of 327 patients (total: 578 teeth) admitted to the Affiliated Hospital of Yanbian University for IMTM extraction from January 2017 to December 2019 was chosen and divided according to gender and age. The correlation between the IMTM and ERR of MSM was analysed, including inclination angle, impaction direction and depth. The relationship of mandibular ascending ramus classification with ERR of MSM was also analysed. In addition, the correlation between the MTM impaction type and the severity of ERR was analysed. The incidence of ERR of MSM in male patients was higher than in females (27.9% vs.17.6%, p = 0.018). The occurrence and the site of ERR showed statistical differences in the inclination angle [(≤20°, 3.6%) vs. (21°-40°, 27.1%) vs. (41°-60°, 27.6%) vs. (61°-80°, 25.6%) vs. (>80°, 31.7%), p <0.001], impaction direction [(Vertical, 1.1%) vs. (Mesial, 32.7%) vs. (Horizontal, 25.3%), p <0.001] and depth of MTM [(Low position, 38.6%) vs. (Median position, 32.0%) vs. (High position, 13.7%), p <0.001]. Also, there was a significant difference in the mandibular ascending ramus type [(Class I, 17.4%) vs. (Class II, 32.3%) vs. (Class III, 44.9%), p <0.001]. In addition, the severity of ERR showed statistical differences in the mesial (40.9%, p<0.05), lower impaction (54.5%, p<0.05) depth of MTM and type III of mandibular ascending ramus (63.6%, p<0.05). The inclination angle, impaction direction, and depth of MTM were the influencing factors for the occurrence and site of ERR. Also, mandibular ascending ramus type was the impact fact. For MTM with mesioangular, lower impaction, and mandibular ascending ramus with type III, the ERR of the MSM was severer.

Preservation of strawberries using chitosan incorporated with lemongrass essential oil: An X-ray computed tomography analysis of the internal structure and quality parameters

Preservation of strawberries using chitosan incorporated with lemongrass essential oil: An X-ray computed tomography analysis of the internal structure and quality parameters

Cone-beam Computed Tomography Analysis of the Root Canal Morphology of Mandibular Incisors Using Two Classification Systems in a Spanish Subpopulation: A Cross-Sectional Study.

This study evaluated the root and canal morphology in permanent mandibular incisors teeth using cone-beam computer tomography imaging in a Spanish subpopulation, and compared these findings with ipsilateral (similarity) and contralateral (symmetry) incisors. In addition, the position of canal splitting was measured. A total of 229 datasets comprising four mandibular teeth each (n=916 incisors) were analysed using Vertucci and Ahmed et al. classifications, and, the similarity and symmetry were calculated. The distance from the cemento-enamel junction (CEJ), and the most coronal canal divergence was measured (if present). The role of sex was also assessed. The Cochran Q Test, LOGIS PROC in SUDAAN, Chi-square, and Kappa were used for the different comparisons. A p-value of less than 0.05 was considered significant. All incisors were single-rooted and no significant differences regarding root canal morphology were found according to the sex of the subjects included in the database. The most common morphology was Vertucci type I/Ahmed et al. 1MI1(65.3% for central and 66.8% for lateral incisors respectively), followed by type III/1MI1-2-1 (31% for central and 30.6% for lateral incisors). 1.8% of the samples were considered as non-classifiable with Vertucci but were classified with codes using the Ahmed et al. system. Similarity values were 74.7% for the left side, and 74.2% for the right side, whereas symmetry values were 90% for central and 84.3% for lateral incisors. In the presence of divergences, the main (SD) distances from the CEJ were for type II/1MI1-2-1 3.8+-0.8 (centrals) 4.0+-0.7 mm (laterals); for type V/1MI1-2 this value ranged between 6.0+-1.8 and 5.5+-1.5 mm, whereas values for 1MI1-2-3-2-1 were 1.8 and 2.1 mm. No significant differences were found when the position of the most coronal divergence was compared between lateral and central incisors for the different morphologies. A high prevalence of Vertucci I/Ahmed et al. 1MI1 configuration was present in mandibular incisors from Spanish individuals. Similarity and symmetry were common, particularly for central incisors. The position of the coronal splitting of the canals varied according to the root canal morphology.

Detailed analysis of inner ear malformations in CHARGE syndrome patients – correlation with audiological results and proposal for computed tomography scans evaluation methodology

ObjectivesThe aim was to describe the spectrum of inner ear malformations in CHARGE syndrome and propose a Computed Tomography (CT) detailed scan evaluation methodology. The secondary aim was to correlate the CT findings with hearing thresholds. MethodsTwenty ears of ten patients diagnosed with CHARGE syndrome were subjected to CT analysis focusing on the inner ear and internal acoustic canal. The protocol used is presented in detail. ASSR results were analyzed and correlated with inner ear malformations. ResultsCochlear hypoplasia type III was the most common malformation found in 12 ears (60%). Cochlear hypoplasia type II, aplasia with a dilated vestibule, and rudimentary otocyst were also identified. In 20%, no cochlear anomaly was found. The lateral Semicircular Canal (SCC) absence affected 100% of ears, the absence of the posterior SCC 95%, and the superior SCC 65%. Better development of cochlea structures and IAC correlated significantly with the lower hearing thresholds. ConclusionThis study demonstrated that rudimentary SCC or a complete absence of these SCCs was universally observed in all patients diagnosed with CHARGE syndrome. This finding supports the idea that inner ear anomalies are a hallmark feature of the CHARGE, contributing to its distinct clinical profile. The presence of inner ear malformations has substantial clinical implications. Audiological assessments are crucial for CHARGE syndrome, as hearing loss is common. Early detection of these malformations can guide appropriate interventions, such as hearing aids or cochlear implants, which may significantly improve developmental outcomes and communication for affected individuals. Recognizing inner ear malformations as a diagnostic criterion presents implications beyond clinical diagnosis. A better understanding of these malformations can advance the knowledge of CHARGE pathophysiology. It may also help guide future research into targeted therapies to mitigate the impact of inner ear anomalies on hearing and balance function. Level of evidence4.

Reject Analysis in Digital Radiography and Computed Tomography: A Belgian Imaging Department Case Study.

Reject analysis is usually performed in digital radiography (DR) for quality assurance. Data for computed tomography (CT) rejects remains sparse. The aim of this study is to help provide a straightforward benchmark for reject analysis of both DR and CT. This retrospective observational study included 107,277 DR and 20,659 CT during 18 months in a tertiary care center. Rejected acquisitions were retrieved by Dose Archiving and Communication System (DACS). The DR and CT reject analysis included reject rates, reasons for rejection and supplementary radiation dose associated with these rejects. 8,904 rejected DR and 514 rejected CT were retrieved. The DR reject rate was 8.3% whereas the CT reject rate was 2.5%. The cumulative effective dose (ED) of DR rejects was 377.3 mSv while the cumulative ED of CT rejects was 1267.4 mSv. The major reason for rejects was positioning for both DR (61%) and CT (44%). This study helps constitute a simple reproducible method to analyze both DR and CT rejects simultaneously. Although CT rejects are less often monitored than DR rejects, the radiation dose associated with CT rejects is much higher, which emphasizes the need to systematically monitor both DR and CT rejects. Investigating the reasons and the most frequently rejected examinations gives an opportunity for improvement of imaging techniques in cooperation with technologists.

Computerized tomography analysis of potential geochemical reactions of carbonate rocks during underground hydrogen storage

The research on Hydrogen (H2) gas has attracted considerable attention as a clean energy source to achieve net-zero carbon emissions. Underground Hydrogen Storage (UHS) in carbonate reservoirs is a suitable solution for safe storage and efficient recovery of hydrogen during the cycling process. However, the potential geochemical reactions between hydrogen and carbonate minerals can influence the storage potential and rock characteristics. Despite the current devotion to evaluating H2-rock interactions, there is a lack of knowledge on the reactivity of carbonate rocks to hydrogen and the potential implications on pore properties. In this work, carbonate rocks were subjected to hydrogen treatment at 75 °C and 1400 psi for 150 days, and a comprehensive Computerized Tomography (μ-CT) scan analysis was performed. The results confirm the occurrence of geochemical reactions of dolomite and calcite with H2, however, the extent of mineral alteration is minimal, and the dissolution/precipitation rates are nearly balanced. Subsequently, insignificant changes in porosity (not exceeding 2 %) and grain expansion are observed. However, we observed unexpected development of fractures within 75–150 days of treatment in the calcite sample, which we believe is related to the de-pressurizing of the samples after 75 days of treatment, and not because of hydrogen reactions. The obtained results demonstrate the high stability of carbonate rocks during short hydrogen storage cycles and imply that the reaction of the carbonate minerals with H2 is very weak within the conditions investigated in this research. This work supports the utilization of carbonate reservoirs for UHS and can be a suitable experimental framework to assist in evaluating the hydrogen reactivity to carbonate reservoirs.

VT ablation based on CT imaging substrate visualization: results from a large cohort of ischemic and non-ischemic cardiomyopathy patients

IntroductionThe eradication of ventricular tachycardia (VT) isthmus sites constitutes the minimal procedural endpoint for VT ablation procedures. Contemporary high-resolution computed tomography (CT) imaging, in combination with computer-assisted analysis and segmentation of CT data, facilitates targeted elimination of VT isthmi. In this context, inHEART offers digitally rendered three-dimensional (3D) cardiac models which allow preoperative planning for VT ablations in ischemic and non-ischemic cardiomyopathies. To date, almost no data have been collected to compare the outcomes of VT ablations utilizing inHEART with those of traditional ablation approaches.MethodsThe presented data are derived from a retrospective analysis of n = 108 patients, with one cohort undergoing VT ablation aided by late-enhancement CT and subsequent analysis and segmentation by inHEART, while the other cohort received ablation through conventional methods like substrate mapping and activation mapping. The ablations were executed utilizing a 3D mapping system (Carto3), with the mapping generated via the CARTO® PENTARAY™ NAV catheter and subsequently merged with the inHEART model, if available.ResultsResults showed more successful outcome of ablations for the inHEART group with lower VT recurrence (27% vs. 42%, p < 0.06). Subsequent analyses revealed that patients with ischemic cardiomyopathies appeared to derive a significant benefit from inHEART-assisted VT ablation procedures, with a higher rate of successful ablation (p = 0.05).ConclusionOur findings indicate that inHEART-guided ablation is associated with reduced VT recurrence compared to conventional procedures. This suggests that employing advanced imaging and computational modeling in VT ablation may be valuable for VT recurrences.Graphical abstract

Printed layers height calibration curve and porosity in laser melting deposition of Ti6Al4V combining experiments, mathematical modelling and deep neural network

PurposePorosity is a commonly analyzed defect in the laser-based additive manufacturing processes owing to the enormous thermal gradient caused by repeated melting and solidification. Currently, the porosity estimation is limited to powder bed fusion. The porosity estimation needs to be explored in the laser melting deposition (LMD) process, particularly analytical models that provide cost- and time-effective solutions compared to finite element analysis. For this purpose, this study aims to formulate two mathematical models for deposited layer dimensions and corresponding porosity in the LMD process.Design/methodology/approachIn this study, analytical models have been proposed. Initially, deposited layer dimensions, including layer height, width and depth, were calculated based on the operating parameters. These outputs were introduced in the second model to estimate the part porosity. The models were validated with experimental data for Ti6Al4V depositions on Ti6Al4V substrate. A calibration curve (CC) was also developed for Ti6Al4V material and characterized using X-ray computed tomography. The models were also validated with the experimental results adopted from literature. The validated models were linked with the deep neural network (DNN) for its training and testing using a total of 6,703 computations with 1,500 iterations. Here, laser power, laser scanning speed and powder feeding rate were selected inputs, whereas porosity was set as an output.FindingsThe computations indicate that owing to the simultaneous inclusion of powder particulates, the powder elements use a substantial percentage of the laser beam energy for their melting, resulting in laser beam energy attenuation and reducing thermal value at the substrate. The primary operating parameters are directly correlated with the number of layers and total height in CC. Through X-ray computed tomography analyses, the number of layers showed a straightforward correlation with mean sphericity, while a converse relation was identified with the number, mean volume and mean diameter of pores. DNN and analytical models showed 2%–3% and 7%–9% mean absolute deviations, respectively, compared to the experimental results.Originality/valueThis research provides a unique solution for LMD porosity estimation by linking the developed analytical computational models with artificial neural networking. The presented framework predicts the porosity in the LMD-ed parts efficiently.