Axial View Research Articles

Analysis of Artefacts in Endodontically Treated Teeth on Cone Beam Computed (CBCT) Images and their Impact on Diagnostic Value

The aim of this paper was to investigate the incidence of artefacts produced by endodontically treated teeth on CBCT images and their impacts the diagnostic value of the image for endodontic purposes. A retrospective analysis of 57 root filled teeth from 40 CBCT scans from UCLAN dental clinic between 2016-2020 was undertaken. Each tooth was split into crown and root section with the incidence of all known artefacts recorded by the binary yes/no variable. Subjective assessment into the diagnostic acceptability of the image in relation to endodontic indications stated in the European Society of Endodontics guidance was done. Age, gender, field of view, tooth type, location, coronal restoration of subject tooth and adjacent teeth were recorded. Statistical analysis (SPSS v28, IBM system) was used to assess the relationship between study factors, artefact expression and the effects on diagnostic quality. Scatter artefacts were present in 100% of samples with Beam Hardening being present in 94.7% of samples. Image Noise, Motion and Aliasing (distortion) artefacts reported an incidence ranging between 0-17.5%. The significance level was set at p<0.05. Of the study characteristics Beam Hardening was affected by tooth type/location, coronal restoration of subject tooth and adjacent tooth whereas Motion and Aliasing artefacts were affected by the number of roots and tooth type/location respectively. Beam Hardening, Image Noise, Motion and Aliasing artefacts were shown to have a statistically significant association with the diagnostic acceptability of the scans of root filled teeth for endodontic purposes especially in the axial and sagittal views. Beam Hardening had the most significant impact on diagnostic quality. This is the first study to show artefact expression is much more prevalent than previously reported and has strong ability to affect the diagnostic acceptability of CBCT scans of root filled teeth taken for endodontic purpose.

(149) Prevalence of Lumbosacral Annular Tears in Individuals with Hard Flaccid Syndrome

Abstract Introduction Hard flaccid syndrome (HFS), characterized by the penis in an unwanted persistent semi-rigid flaccid state, is an acquired, painful, and bothersome sexual dysfunction that is poorly understood. We have previously postulated that HFS is, in part, a consequence of pathological activation of a somato-visceral and/or a viscero-visceral reflex that we term the “pelvic/pudendal-hypogastric” reflex. In patients with HFS, physical examination reveals a hypercontracted flaccid penis that feels hard on palpation. Biological complaints include penile morphometric changes such as wrinkles or indents; cold-feeling glans with decreased penile sensation; urinary symptoms such as decreased force of stream; constipation; high tone pelvic floor; perineal and penile pain during ejaculation; and erectile dysfunction. Since there is limited understanding of HFS and its pathophysiologic triggers, men with these complaints often seek help from online support groups. Objective To assess the prevalence of lumbosacral annular tears in individuals participating in an HFS online support group and compare this to the prevalence reported in asymptomatic individuals in the peer-reviewed literature. Methods A sexual medicine clinic patient with HFS likely from a lumbosacral annular tear causing sacral radiculopathy who leads an HFS online support group shared his information regarding the suspected pathophysiology. Consequently, other members of the group contacted the sexual medicine clinic to share lumbar MRI images for the spine surgeon to read. All lumbar MRIs had been performed within the last year. They were uploaded to an image sharing service for the spine surgeon to read the sagittal and axial views to assess for the presence of lumbosacral annular tears. For comparison, the literature was reviewed regarding the prevalence of lumbosacral spine disease in asymptomatic individuals. Results A total of 21 individuals, mean age 28 (range 19-42) years, with symptoms consistent with HFS contacted our sexual medicine clinic. Symptoms were verified during the courtesy triage call after which a lumbar MRI was submitted by each individual for evaluation. 16/21 (76%) had surgically treatable annular tears, the most common location being L5-S1 and L4-L5. In addition to HFS symptoms, 38% had concomitant complaints of low back pain and lower extremity sciatica. In a systematic review of 33 peer-reviewed articles reporting imaging findings for >3000 asymptomatic individuals, the prevalence of lumbosacral annular tear varied from 19% to 29% in individuals aged 20 to 80 years [Brinjikji et al, 2015]. Conclusions There is a higher prevalence of lumbosacral annular tears among HFS individuals in this support group who had a lumbar MRI compared to the rate in asymptomatic individuals from peer-reviewed literature. This further supports our hypothesis that HFS is the result of a hyperactive “pelvic/pudendal-hypogastric” reflex. In those men with lumbosacral annular tears, HFS may be triggered by the cauda equina pathology causing sacral radiculopathy that reflexively induces excess sympathetic activity in the efferent hypogastric nerve causing the unwanted HFS symptoms. Disclosure No.

Root canal morphology of anterior permanent teeth in Jordanian population using two classification systems: a cone-beam computed tomography study

BackgroundAdequate knowledge of root canal morphology and its variation is essential for success of root canal treatment and to overcome treatemnt failure. The aim of this study was to investigate the root and canal morphology of mandibular anterior teeth using 2 classification systems.Methods3342 lower anteriors were evaluated from 557 CBCT scans. The images were examined in sagittal, axial and coronal views using a CS 3D imaging software (V3.10.4, Carestream Dental). Demographic data recorded, the number of roots and canal’s morphology were described according to Vertucci and Ahmed classifications.ResultsFrequency of Type I configuration was significantly the highest in incisors and canines (76%, N = 2539), followed by Type III (20.6%, N = 687). Type II (1.1%, N = 37), IV (1.1%, N = 37), and V (0.3%, N = 11) were rarely encountered. 0.9% (N = 31) of the teeth could not be classified with the Vertucci System. The frequency of 2 roots (2MA in Ahmed classification) which has no correspondence in the Vertucci classification, was 1.1% (N = 38), it was significantly higher in canines and in females (35 canines and 3 laterals). A moderate correlation in root canal morpology was found between the left and right sides (V > 0.30). 80% (N = 2538) of the teeth did not exhibit any divergence/merging. The bifurcation level occurred mostly in the middle third of the root.ConclusionsOne fourth of anterior teeth had variation from the simple type I canal configuration and therefore requires attention during treatment. The new classification system offers a more accurate and simplified presentation of canal morphology.Clinical relevanceThe prevalence and mid root bifurcation of second canal in lower anteriors requires attention to ensure adequate quality root canal treatment without compromising the integrity of teeth.

Determination of the radioanatomical factors related to the position of facial nerve in accessing jugular foramen and carotid artery in temporal bone

IntroductionPreservation of the facial nerve is of great importance in temporal bone surgeries. We intend to investigate the measurements of the radioanatomical factors related to the position of the facial nerve in accessing jugular foramen and internal carotid artery (ICA) in temporal bone of patients who were candidates for temporal high resolution computed tomography (HRCT) scan. MethodsIn this correlation cross-sectional study, samples were selected from patients referred to Amir Alam Hospital who were previously candidates for temporal HRCT. Radioanatomic factors were evaluated in three axial, coronal and sagittal views. Analyzes were performed using descriptive statistics, correlation analysis and factor analysis. ResultsA total of 173 samples were investigated. The most reliable radioanatomical factor based on coefficient of variation (CV) was the distance of the 7th nerve to the temporomandibular joint (TMJ) in the inferior to the cochlea in the sagittal view (variable name S2) (CV = 8.1%) and then the distance from the 7th nerve to the TMJ in the inferior section of the cochlea in the axial view (variable name AI3) (CV = 8.4%). Based on correlation analysis and then confirmatory factor analysis, three common latent factors were identified (overall R2 = 0.999). ConclusionThe results of this study can be used for two purposes. First, the direct use of the estimated measures in surgical operations, and the second is more advanced modeling to choose the approach in the surgical operation and how to implement that approach. For the first aim, the two factors AI3 and S2 were the most reliable radioanatomical factors in different people. For the second aim, the three-dimensional understanding of the obtained measurements and the further identification of the anatomical nature of the latent factors can help in choosing the approach in surgery.

Exercise-Related Physical Activity Relates to Brain Volumes in 10,125 Individuals.

The potential neuroprotective effects of regular physical activity on brain structure are unclear, despite links between activity and reduced dementia risk. To investigate the relationships between regular moderate to vigorous physical activity and quantified brain volumes on magnetic resonance neuroimaging. A total of 10,125 healthy participants underwent whole-body MRI scans, with brain sequences including isotropic MP-RAGE. Three deep learning models analyzed axial, sagittal, and coronal views from the scans. Moderate to vigorous physical activity, defined by activities increasing respiration and pulse rate for at least 10 continuous minutes, was modeled with brain volumes via partial correlations. Analyses adjusted for age, sex, and total intracranial volume, and a 5% Benjamini-Hochberg False Discovery Rate addressed multiple comparisons. Participant average age was 52.98±13.04 years (range 18-97) and 52.3% were biologically male. Of these, 7,606 (75.1%) reported engaging in moderate or vigorous physical activity approximately 4.05±3.43 days per week. Those with vigorous activity were slightly younger (p < 0.00001), and fewer women compared to men engaged in such activities (p = 3.76e-15). Adjusting for age, sex, body mass index, and multiple comparisons, increased days of moderate to vigorous activity correlated with larger normalized brain volumes in multiple regions including: total gray matter (Partial R = 0.05, p = 1.22e-7), white matter (Partial R = 0.06, p = 9.34e-11), hippocampus (Partial R = 0.05, p = 5.96e-7), and frontal, parietal, and occipital lobes (Partial R = 0.04, p≤1.06e-5). Exercise-related physical activity is associated with increased brain volumes, indicating potential neuroprotective effects.

[Translated article] Insertion of S1 iliosacral screws in the computed tomography room: An alternative to improve safety in the percutaneous management of posterior pelvic ring injuries

IntroductionThe main complication of percutaneous iliosacral screw fixation is implant malposition, which can lead to vascular and nerve damage. The anatomical variability of the sacrum can make screw insertion difficult under fluoroscopic guidance. Among the methods described to improve the accuracy of this technique, stands out the use of computed tomography (CT). The aim of this study is to compare the results of iliosacral screw insertion with fluoroscopy or CT navigation. MethodologyRetrospective cohort study of 66 iliosacral screws in 56 patients during 11 years. The screws were inserted with fluoroscopy in the operating room or with CT in the radiodiagnosis area. We collected data on patient characteristics, lesions, treatment, and clinical and radiological results. ResultsForty-seven screws were inserted with fluoroscopy and 19 with CT. A percentage of 18.2 of screws perforated the S1 osseous corridor. All of them were inserted with fluoroscopy guidance (0 vs. 34%; p<0.01). Those operated with CT accumulated more sacral dysmorphism criteria than those operated with fluoroscopy (2.2 vs. 1.6; p=0.02). The S1 corridor on the axial CT view was narrower in those in whom perforation had occurred (18.8 vs. 21.0mm; p=0.02). Two cases with perforation developed S1 radiculalgia. Two endopelvic screws had to be removed. ConclusionWe advise the use of CT guidance for iliosacral screw insertion in patients with sacral dysmorphism or narrow S1 corridors in facilities where other navigation methods are not available.

Does a collecting system injury with grade iv renal blunt trauma always need urinary intervention?

This study aimed to identify the characteristics associated with the need for urinary intervention for a blunt renal injury with collection system involvement using a computed tomography (CT) protocol for trauma. Abdominal CT images of patients with blunt renal injuries from 2016 to 2020 were reviewed. Patients with low-grade renal trauma, non-collecting system involvement, American Association for the Surgery of Trauma grade V shattered kidney, and emergent nephrectomy were excluded. The largest perinephric mass thickness was measured in the axial view using CT, and a cutoff value was obtained using a receiver-operating characteristic curve analysis. Risk factors for further urinary intervention were analyzed. Among the 70 patients included in this study, those with perinephric mass thicknesses < 25mm (n = 36) had a significantly lower rate of urinary intervention than those with perinephric mass thicknesses ≥ 25mm (0 vs. 5; p = 0.023). There was no significant difference in the follow-up durations of the groups (19days vs. 38days; p = 0.198). More than 90% of the perinephric mass in the < 25mm group resolved within a median follow-up duration of 38days, whereas nearly half of the ≥ 25mm group had a residual perinephric mass during a median follow-up duration of 19days. The initial CT protocol for trauma was useful for predicting the need for further urinary interventions for collecting system injuries. A perinephric mass thickness < 25mm is predictive of a low likelihood of requiring urinary intervention.

Clinical trainee performance on task-based AR/VR-guided surgical simulation is correlated with their 3D image spatial reasoning scores.

This paper describes a methodology for the assessment of training simulator-based computer-assisted intervention skills on an AR/VR-guided procedure making use of CT axial slice views for a neurosurgical procedure: external ventricular drain (EVD) placement. The task requires that trainees scroll through a stack of axial slices and form a mental representation of the anatomical structures in order to subsequently target the ventricles to insert an EVD. The process of observing the 2D CT image slices in order to build a mental representation of the 3D anatomical structures is the skill being taught, along with the cognitive control of the subsequent targeting, by planned motor actions, of the EVD tip to the ventricular system to drain cerebrospinal fluid (CSF). Convergence is established towards the validity of this assessment methodology by examining two objective measures of spatial reasoning, along with one subjective expert ranking methodology, and comparing these to AR/VR guidance. These measures have two components: the speed and accuracy of the targeting, which are used to derive the performance metric. Results of these correlations are presented for a population of PGY1 residents attending the Canadian Neurosurgical "Rookie Bootcamp" in2019.

TVS-guided cervical strain elastography is more effective than measuring cervical length as an independent predictor of spontaneous preterm delivery in asymptomatic, high-risk women during the mid-trimester

Introduction TVS (Transvaginal Sonography) guided Cervical strain elastography (CSE) is now available in tertiary referral centers of LMICs (Low- and Middle-Income Countries). TVS cervical length (CL) assessment is being used routinely. Still, elastography is not used in clinical settings, although enough evidence suggests good predictive value towards sPTD (spontaneous Preterm Delivery). The clinical utility of elastography has not been tested among high-risk populations of LMICs for the prediction of sPTD. Aim To test the performance of TVS-CSE in predicting sPTD among asymptomatic women in the mid-trimester at risk of sPTD either due to clinical factors or due to a short cervix. Method Prospective observational study performed at a tertiary hospital in South India. Asymptomatic pregnant women between 16 and 24 weeks who had one or more clinical risk factors for sPTD or CL <2.5 cm were included. GE Voluson E-8 ultrasound machine was used. After CL measurement, elastography color coding was noted around the internal-os in the sagittal view. The strain ratio (SR) was calculated using the trace method on three ROIs (Region of Interest): Internal-os in sagittal view (IN), whole cervix in sagittal view (WN), and internal-os in axial view (AN). Reference Tissue (RT) of similar size and depth was chosen in the darkest blue region on elastography (stiffest area) outside the cervix, posterior/lateral to the cervix over the ligament insertion. Lower the SR – softer the cervix. Two trained fetal medicine consultants performed the initial 57 cases until intra/inter-observer correlation was satisfactory. Delivery before 37 weeks (after 26 weeks), in which the process of labor has begun spontaneously, or labor was induced after PPROM—was considered as sPTD. SRs were assessed to determine how well they could predict sPTD independently or combined with cervical length. Results Out of 221 recruited,17 were lost to follow-up after 32 weeks; 204 were delivered in our hospital. Irrespective of the route of delivery, 71 (34.8%) had sPTD. Of the remaining 133, 106 delivered at term, and 27 underwent medically indicated PTD. Apart from multiple pregnancies, no other preterm-related risk factors (including CL < 2.5 cm) showed significant association with sPTD. Red CSE pattern around internal-os was associated with a significantly higher (54.5%) incidence of sPTD. CLs were similar (3.63 ± 0.67 vs. 3.63 ± 0.80, p = .981) whereas SRs in all three ROIs were significantly lower among sPTD group versus no sPTD group (IN:0.65 ± 0.29 vs 0.79 ± 0.30 p = .001, WN:0.34 ± 0.13 vs 0.39 ± 0.15, p = .013, AN:0.37 ± 0.16 vs 0.48 ± 0.26, p = .002, respectively). Using ROC curves, while CL was not predictive (AUROC 0.49, p = .81), SRs showed moderate predictive value toward sPTD with the best AUC of 0.624 (p = .003) at IN. Prediction was slightly better for early sPTD <32 weeks (AUC 0.653 p = 0.03). The best cutoff for SR at IN was 0.72, below which there was a moderate accuracy in predicting sPTD (sensitivity 52.11%, specificity 60.9%, PPV 41.57%, NPV 70.44%, diagnostic OR 1.69 and overall accuracy of 57.84%). A weak positive correlation is seen between IN and CL (Pearson’s correlation R = 0.181). Multi-variable binary logistic regression analysis suggested that SRs at IN (Adjusted OR − 0.259 CI 0.079–0.850), AN (Adjusted OR 0.182 CI 0.034–0.963), Multiple Pregnancy (Adjusted OR 3.5 CI 1.51–8.13) and previous sPTD/PPROM (Adjusted OR 2.72 CI 0.97–7.61) independently predicted sPTD. Conclusions TVS CSE performed better than CL as an independent predictive tool toward sPTD, although predictive efficacy was modest at best. Since technology is now available in high-end USG machines in tertiary care centers, we propose optimal utilization of CSE in LMICs to triage at-risk populations since low SRs are strongly associated with sPTD.

I3Net: Inter-Intra-slice Interpolation Network for Medical Slice Synthesis.

Medical imaging is limited by acquisition time and scanning equipment. CT and MR volumes, reconstructed with thicker slices, are anisotropic with high in-plane resolution and low through-plane resolution. We reveal an intriguing phenomenon that due to the mentioned nature of data, performing slice-wise interpolation from the axial view can yield greater benefits than performing super-resolution from other views. Based on this observation, we propose an Inter-Intra-slice Interpolation Network (I3Net), which fully explores information from high in-plane resolution and compensates for low through-plane resolution. The through-plane branch supplements the limited information contained in low through-plane resolution from high in-plane resolution and enables continual and diverse feature learning. In-plane branch transforms features to the frequency domain and enforces an equal learning opportunity for all frequency bands in a global context learning paradigm. We further propose a cross-view block to take advantage of the information from all three views online. Extensive experiments on two public datasets demonstrate the effectiveness of I3Net, and noticeably outperforms state-of-the-art super-resolution, video frame interpolation and slice interpolation methods by a large margin. We achieve 43.90dB in PSNR, with at least 1.14dB improvement under the upscale factor of ×2 on MSD dataset with faster inference.

Enhancing Brain Tumor Assessment: A Comprehensive Approach using Computerized Diagnostic Tool and Advanced MRI Techniques

Assessment of brain tumour using Three-Dimensional Magnetic Resonance Imaging (3D MRI) is computationally multifaceted task. Currently, hospitals employ 2D MRI scans, followed by manual evaluation by experienced doctors, aided by a Computerized Diagnostic Tool (CDT). This research aims to develop an advanced CDT to significantly enhance the accuracy of brain tumor assessment. The CDT presented in this study evaluates Axial-View (AV), Coronal-View (CV), and Sagittal-View (SV) MRI images. It encompasses a comprehensive pipeline, including pre-processing, post-processing, feature extraction, feature selection, and categorization phases. Various tumor segmentation techniques, including active contour, level-set, watershed, and region growing, are thoroughly explored. Additionally, a comparative analysis of classification methods such as SVM, ANFIS, k-NN, Random Forest, and Adaboost is conducted. Experimental validation using the BRATS 2016 dataset and real-time 2D MRI data demonstrates that the proposed CDT consistently achieves an average classification accuracy exceeding 95% in tumor-based categorization. This research represents a significant advancement in brain tumor assessment, leveraging machine learning and advanced MRI techniques to improve diagnostic precision.

Accuracy of imaging grading in comparison to open laminectomy to evaluate pedicle screws positioning.

Prospective experimental study. To compare the accuracy of O-Arm-acquired radiographic and computed tomography (CT) evaluation of thoracic pedicle screw placement with open laminectomy in a simulation laboratory. Improving surgical safety and procedural efficiency during thoracic posterior spine instrumentation is essential for decreasing complication rates and possible related risks. The most common way of verifying the position of pedicle screws during the surgical procedure and immediately postoperatively is to acquire intraoperative fluoroscopic images and plain radiographs of the spine, respectively. Laboratory simulated surgery is a valuable tool to evaluate the accuracy of those exams. Twenty simulation models of scoliosis from T3 to T7 were instrumented by five spine fellows (total of 200 pedicle screws), followed by radiographic and CT images acquired with the assistance of the O-Arm which were evaluated by three independent raters. A fellowship-trained spine neurosurgeon performed laminectomies on the instrumented levels and assessed pedicle integrity (gold standard). Forty-eight breaches were identified in the axial direct view after laminectomy. Of those, eighteen breaches were classified as unacceptable. Regarding the sagittal direct view, four breaches were observed, three of which were classified as unacceptable. Overall, both O-arm radiographic and CT evaluations had a significantly high negative predicted value but a low positive predicted value to identify unacceptable breaches, especially in the sagittal plane. The frequency of missed breaches by all three examiners was high, particularly in the sagittal plane. Postoperative evaluation of pedicle screws using O-arm-acquired radiographic or CT images may underdiagnose the presence of breaches. In our study, sagittal breaches were more difficult to diagnose than axial breaches. Although most breaches do not have clinical repercussions, this study suggests that this modality of postoperative radiographic assessment may be inaccurate. 4.

A Rare Case of Pleomorphic Adenoma in the Left Submandibular Salivary Gland

Pleomorphic adenomas, which are benign tumours of the salivary glands, are most commonly found in the parotid gland and comparatively infrequently seen in the submandibular gland. These benign mixed tumours, known as pleomorphic tumours, are composed of different types of myoepithelium, epithelium, and mesenchyme. Regardless of the histologic type, parotid gland neoplasms result in distinct swellings in front of and below the ear. With the exception of neglected malignant tumours, both benign and malignant lesions are normally palpable when they are first discovered. Malignancies are often discovered more quickly due to their rapid growth, even though benign tumours are known to exist for many months to years before gaining clinical attention. Ultimately, there are no reliable clinical criteria to distinguish between benign and malignant lesions. A 58-year-old female patient presented to the general surgery outpatient department with a six-month history of a firm, palpable, slow-growing, painless, freely mobile mass in the submandibular region that was not attached to the surrounding tissue, bone, or skin. There was no significant past history, and the patient was not on any medication. Axial and coronal views of the Computed Tomography (CT) scan showed a well-defined radiolucent mass in the medial aspect of the left submandibular gland. The patient underwent surgical exploration and excision of the mass under general anaesthesia, and the excised specimen was sent for histopathological examination. The entire gland was dissected freely and removed, with utmost care taken not to affect the nearby neurovascular structures. No enlarged lymph nodes were noted. The histopathological examination of the biopsy specimen revealed features of pleomorphic adenoma. Surgery is the treatment of choice for pleomorphic adenoma, and the tumour tissue must be completely removed because any residual tumour tissue has a high risk of recurrence or transformation into a malignant tumour. The patient was followed up for more than two years with no signs of recurrence.

Prevalence and morphology of middle mesial canal in mandibular first molars in an Indian sub-population: A cone-beam computed tomographic analysis

Aim: The aim of this study was to check for the prevalence and morphology of middle mesial (MM) canals in mandibular first molars in an Indian population divided as per the different zones of the country using cone-beam computed tomography (CBCT) scans. Methods: A total of 452 CBCT scans were selected according to the inclusion and exclusion criteria on December 2021. The scans were obtained from five different zones of the country with 80–100 scans selected from each zone. They were checked in an axial view to see for the presence of a MM canal (MMC) and if present, were confirmed in a coronal view. Results: Of the 452 scans viewed, 39 showed the presence of MMCs (8.6%). Bilateral presence was seen in 8 scans (1.8%). Hence, overall, 47 molars out of 904 examined showed the presence of MMCs. Thus, the tooth prevalence rate for the presence of MMC was 5.2%. Seventy percent of teeth presenting with MMCs showed two apical exits. Males showed more prevalence when compared to the female population (10.25% vs. 6.88%, P &lt; 0.05). Furthermore, with increasing age, there was a consistent decrease in the incidence of MMCs (P &lt; 0.05). Conclusion: Overall, the prevalence of MMCs in an Indian sub-population is 8.6%. Although on a lower range compared to other population, careful exploration is necessary to avoid missing the MMC which might lead to failure of treatment. Age and gender are also found as the important factors that influence the presence of a MMC.

Relationship of pericardial effusion thickness and volume measurement by non-ECG gated computed tomography

Background: An accurate estimation of pericardial fluid volume could improve communication between radiologists and the multidisciplinary team. Objective: To find the correlation between the volume and thickness of pericardial effusion measured by CT scan. Materials and Methods: The chest CT scans of 38 patients with pericardial effusion were measured for volume using manual segmentation and for thickness on axial and 3-chamber planes from the anterior and posterior aspects. The correlation between volume and thickness was evaluated using Pearson’s correlation coefficient (r). The reliability of the measurements was tested using intraclass correlation coefficient (ICC) and Bland-Altman analysis. Results: There was a fair to moderately strong correlation between the volume and thickness of pericardial effusion (r= 0.435-0.625, p= &lt;0.01). An ICC of 0.452-0.703 indicated moderate inter-observer agreement. The best measurement is the sum of the anterior and posterior thicknesses on the axial plane (ICC of 0.703) that correlates well with the volume (r= 0.624). A linear regression equation demonstrating the relationship between pericardial effusion thickness and the effusion volume was computed as; Volume (mL) = 73 + 71*(the sum of anterior and posterior thicknesses on axial view in cm). The equation was applied: a value of approximately 3 cm = small, 6 cm = moderate, and 9 cm = large pericardial effusion. Conclusion: There is a moderate correlation between the sum of the anterior and posterior pericardial thicknesses and the pericardial volume. Our preliminary formula enables a rapid estimation of the effusion volume. Further validation and refinement of the formula in a larger, prospective study is needed.

Isotropic multi-scale neuronal reconstruction from high-ratio expansion microscopy with contrastive unsupervised deep generative models

Background and objectiveCurrent methods for imaging reconstruction from high-ratio expansion microscopy (ExM) data are limited by anisotropic optical resolution and the requirement for extensive manual annotation, creating a significant bottleneck in the analysis of complex neuronal structures. MethodsWe devised an innovative approach called the IsoGAN model, which utilizes a contrastive unsupervised generative adversarial network to sidestep these constraints. This model leverages multi-scale and isotropic neuron/protein/blood vessel morphology data to generate high-fidelity 3D representations of these structures, eliminating the need for rigorous manual annotation and supervision. The IsoGAN model introduces simplified structures with idealized morphologies as shape priors to ensure high consistency in the generated neuronal profiles across all points in space and scalability for arbitrarily large volumes. ResultsThe efficacy of the IsoGAN model in accurately reconstructing complex neuronal structures was quantitatively assessed by examining the consistency between the axial and lateral views and identifying a reduction in erroneous imaging artifacts. The IsoGAN model accurately reconstructed complex neuronal structures, as evidenced by the consistency between the axial and lateral views and a reduction in erroneous imaging artifacts, and can be further applied to various biological samples. ConclusionWith its ability to generate detailed 3D neurons/proteins/blood vessel structures using significantly fewer axial view images, IsoGAN can streamline the process of imaging reconstruction while maintaining the necessary detail, offering a transformative solution to the existing limitations in high-throughput morphology analysis across different structures.

Importance of computed tomography in posterior malleolar fractures: Added information to preoperative X-ray studies.

Ankle fractures are common lesions of the lower limbs. Approximately 40% of ankle fractures affect the posterior malleolus (PM). Historically, PM osteosynthesis was recommended when PM size in X-ray images was greater than 25% of the joint. Currently, computed tomography (CT) has been gaining traction in the preoperative evaluation of ankle fractures. To elucidate the similarity in dimensions and to correlate PM size in X-ray images with the articular surface of the affected tibial plafond in the axial view on CT (AXCT) of a PM fracture. Eighty-one patients (mean age: 39.4 ± 13.5 years) were evaluated (54.3% were male). Two independent examiners measured PM size in profile X-ray images (PMXR) and sagittal CT (SAGCT) slices. The correlation of the measurements between the examiners and the difference in the PM fragment sizes between the two images were compared. Next, the PM size in PMXR was compared with the surface of the tibial plafond involved in the fracture in AXCT according to the Haraguchi classification. The correlation rates between the examiners were 0.93 and 0.94 for PMXR and SAGCT, respectively (P < 0.001). Fragments were 2.12% larger in SAGCT than in PMXR (P = 0.018). In PMXR, there were 56 cases < 25% and 25 cases ≥ 25%. When PMXR was < 25%, AXCT corresponded to 10.13% of the tibial plafond. When PMXR was ≥ 25%, AXCT was 24.52% (P < 0.001). According to the Haraguchi classification, fracture types I and II had similar PMXR measurements that were greater than those of type III. When analyzing AXCT, a significant difference was found between the three types, with II > I > III (P < 0.001). PM fractures show different sizes using X-ray or CT images. CT showed a larger PM in the sagittal plane and allowed the visualization of the real dimensions of the tibial plafond surface.

Feasibility and safety of minimally invasive calcaneal osteotomy (MICO) through amedial approach: acase-control study.

Minimally invasive calcaneal osteotomy (MICO) is already an established surgical procedure for correcting hindfoot deformities using alateral approach. So far, no description of amedial approach for MICO has been published. Between August 2022 and March 2023, 32consecutive patients (MICO with medial approach, MMICO: n = 15; MICO with lateral approach, LMICO: n = 17) underwent MICO as part of complex reconstructive surgery of the foot and ankle with concomitant procedures. The amount of correction in the axial view of the calcaneus and consolidation rates were evaluated radiographically. Subjective satisfaction, stiffness of the subtalar joint, and pain level (numeric rating scale, NRS) at the level of the heel were assessed clinically. The last follow-up was at 6months. All osteotomies consolidated within 6months after surgery. Displacement of the tuber was 9 mm on average in either group. Relevant subtalar joint stiffness was detected in 5MMICO and 6LMICO patients. No relevant differences between the groups were detected for wound healing problems, nerve damage, heel pain or patient satisfaction. In this study lateral and medial approaches for MICO were performed. Similar degrees of correction and low complication rates were found in both groups. The medial approach for MICO is safe and can be beneficial regarding patient positioning and arrangement of the C‑arm.

Utility of 3D reformatted images in the diagnosis of sternoclavicular joint injury.

The purpose of this study is to evaluate the ability of musculoskeletal radiologists to diagnose sternoclavicular joint injuries in the standard CT imaging planes compared to 3D volume rendered images to define the most accurate plane to improve prospective diagnosis. A retrospective query of our institutional database was performed. Twenty-six patients with a diagnosis of sternoclavicular joint injury, who had been evaluated with CT and treated by orthopedic surgery, and 30 control patients who did not have a sternoclavicular joint injury were included for analysis. Two blinded radiologists with specialty training in musculoskeletal radiology independently reviewed axial, coronal, sagittal, and 3D reformatted CT images and documented whether injury was present or not present. Accuracy was good for both radiologists on all views. It was lowest on the sagittal view for both readers. Accuracy was highest for the 3D view. When comparing the accuracy of the four views for each radiologist, there was a significant difference for Radiologist A, whose 3D images were more accurate compared to the axial and sagittal views. There was no significant difference for Radiologist B. There was good inter-reader agreement, which was highest on the 3D images. 3D volume renderings of the sternoclavicular joints have the potential to improve radiologist accuracy for detection of sternoclavicular joint injury/dislocation in the setting of chest well trauma, which could decrease instances of missed or delayed diagnosis.

A 2.5D residual U‐Net for improved amyloid PET harmonization preserving spatial information

AbstractBackgroundMultiple amyloid tracers with varying characteristics pose a significant challenge to standardized interpretation and quantification of amyloid PET measurements. We previously demonstrated that a deep learning based 2D residual inception encoder‐decoder network (RIED‐Net) architecture improved harmonization of florbetapir (FBP) and PiB PET. However, 2D networks fail to capture spatial information among image slices and 3D networks with more parameters require larger datasets and powerful computation for training. Here, we investigate the performance of a 2.5D approach to further improve harmonization preserving spatial information.Method92 PiB‐FBP image pairs from Open Access Series of Imaging Studies (OASIS) were processed using established pipelines to extract regional standard uptake value ratios (SUVRs), mean cortical SUVRs (mcSUVRs), and SUVR images. A 2.5D U‐Net model with residual connections was implemented to learn the nonlinear mappings from the image pairs. Input to the network is a stack of 3 adjacent FBP slices along a particular view, providing extra spatial information about volumetric data. The output of network is a stack of corresponding 3 PiB slices. Multi‐slice output avoids averaging/blurry effects common in traditional 2.5D approaches. 10‐fold cross‐validation was implemented on axial, coronal and sagittal views separately to generate synthetic PiB SUVR imaging from FBP data. The average synthetic PiB image from axial, coronal and sagittal views was used for performance evaluation. Correlation was evaluated between the virtual PiB mcSUVR derived from imputed PiB vs. the real PiB mcSUVR and voxel‐wise between the imputed vs. real PiB SUVR images.ResultThe agreement of mcSUVR improved from r = 0.90 between PiB and FBP to r = 0.95 between synthetic and real PiB SUVR images (p&lt;0.0001) in cross‐validation dataset. Additionally, imputed PiB SUVR images were visually more similar to real PiB SUVR images than FBP. Voxel‐wise correlation improved from 0.88 to 0.93 (p&lt;0.0001).ConclusionOur proposed 2.5D Residual U‐Net for synthetic imaging was able to learn voxel‐wise nonlinear associations between FBP and PiB images. The model trained in 2.5D approach with additional spatial information, was able to significantly improve agreements of amyloid burden measurement from two tracers and generate PiB SUVR images that are visually more similar to real PiB SUVR images than FBP.