Lateral Projections Research Articles

Structural projections to the nucleus accumbens link to impulsive components of human risk preference

Abstract Functional responses in the Nucleus Accumbens (NAcc) to risk- and reward-related cues can predict real-life risk-taking behavior. Since NAcc activity depends on neurotransmission from connected brain regions, projections to the NAcc may also predict risk preference. To quantify risk preference, we employed latent variables previously derived in a comprehensive, independent study examining the psychometric structure of risk preference, which yielded a general risk preference factor as well as several specific factors, including a factor capturing impulsivity. Informed by previous work, we preregistered a set of hypotheses concerning the association between different risk preference factors and fractional anisotropy (or FA, which is sensitive to fiber coherence) for projections to the NAcc from Medial PreFrontal Cortex (MPFC), Anterior Insula, Amygdala, and an inferior tract from the Ventral Tegmental Area (iVTA). We tested our hypotheses in a community sample of 125 healthy human adults. As predicted, bilateral iVTA-NAcc tract FA showed a negative correlation with a psychometric factor that captured impulsivity, generalizing findings from prior research. Also as predicted, FA of the bilateral Amygdala-NAcc tract was positively associated with the impulsivity factor. Contrary to predictions, however, we observed no robust associations between the general risk preference factor and FA for projections from bilateral MPFC, right Anterior Insula, or bilateral Amygdala to the NAcc. Notably, exploratory unilateral analyses revealed an association between the general risk preference factor and left MPFC-NAcc tract FA. Taken together, these findings suggest that impulse control as a facet of risk preference maps onto specific neurobiological targets, while more general facets of risk preference may be supported by structural properties of lateral fronto-striatal projections. Although the exact associated functional mechanisms remain to be fully clarified, conNAcctomic approaches like the one presented here could pave the way for further research into the physiological foundations of risk preference and related constructs.

An MRI-Based Method for the Morphologic Assessment of the Anterior Tibial Tuberosity.

Background: A prominent anterior tibial tuberosity (or tibial tubercle) can be seen in ongoing Osgood-Schlatter disease (OSD) in teenagers or as a sequela of OSD in adults. Current radiological methods do not provide a true anatomical assessment of the tibial tuberosity; therefore, we proposed and developed a Magnetic Resonance Imaging (MRI)-based method for measuring the anterior tibial tuberosity index, aiming to deal with the current lack of effective techniques for accurately assessing these particular morphologic features. Methods: A retrospective study included 47 knees with tibial tuberosity measurements on both true sagittal MPR images of 3D proton density (PD)-weighted MRI sequences and lateral knee radiographs. The same landmarks were followed and the anterior tibial tuberosity index (ATTI) was measured. Results: The comparison of the results obtained by the two methods demonstrates that our method is reliable and reproducible with substantial inter- and intra-observer agreement. The intraclass correlation coefficient was 0.9250 (95% CI: 0.8654 to 0.9582), indicating excellent reliability between the two methods. A strong positive correlation was also identified, with a correlation coefficient of r = 0.8746 (95% CI: 0.7845 to 0.9286, p < 0.0001) between the two methods. No significant deviation from linearity was observed by analyzing the linear model validity using the cusum test (p = 0.62). Conclusions: Based on these results, we encourage the use of 3D PD-weighted MRI sequences for the measurement of the anterior tibial tuberosity on MRI in order to avoid unnecessary exposure to ionizing radiation and potentially obtain a more accurate measurement. Future larger studies should also explore the benefit of utilizing 3D sequences over 2D lateral projections to minimize measuring bias.

Contralateral Sublaminar Approach in Lumbar Spine With Unilateral Biportal Endoscopy

Unilateral biportal endoscopy (UBE) can be used to treat common lumbar pathologies, such as synovial facet cysts, foraminal disc herniations, and foraminal stenosis via a contralateral sublaminar approach. Due to the ultra-minimally invasive technique, UBE can reduce damage to anatomical structures, thereby reducing postoperative pain and allowing faster recovery. The patient is placed prone on a Wilson frame or bolsters. Fluoroscopy is used to identify the midline and medial pedicle line in the anterior-posterior projection. Spinal needles can aid to identifying portals’ trajectory in the lateral fluoroscopic projection. The procedure is performed via 2 separate portal incisions. The endoscope is introduced through the viewing portal and the surgical instruments through the working portal. Soft tissue dissector is used to create a working area over the spinous process-lamina junction. Bony shaving and drilling start at the target area and continue medially underneath the base of the spinous process until the midline and contralateral ligamentum flavum are identified. Contralateral ligamentum flavum is excised, exposing thecontralateral thecal sac, traversing nerve root, and lateral recess. The contralateral disc space, annulus, and superior articulating process are then identified and the offending pathology can be addressed under direct visualization. Meticulous hemostasis and close attention to outflow should be maintained to reduce the risk of complications. The steps of this procedure closely resemble those of traditional microscopic “over-the-top” techniques, including the surgical instruments used through the working portal. In this video, authors present the surgical technique of the contralateral sublaminar approach in the lumbar spine with UBE.

Initial results of the READY registry: comparison of visual and physiological lesion characterization and the effect of hydrostatic pressure correction

Abstract We aimed to compare resting Pd/Pa, FFR, and distal RFR values with and without hydrostatic pressure correction. Our main goal was to assess the influence of this correction on cut-off value-based decision-making for each physiological parameter. Data from patients enrolled in two centers of the READY registry (NCT04857762) were analyzed. Center 1 employed catheter and pressure sensor height differences defined from lateral angiographic projection for hydrostatic pressure correction, while Center 2 utilized average pressure differentials from published data. In Center 1, the height difference underlying the hydrostatic pressure correction did not differ significantly from the average values published in previous publication (-5.22±1.1cm for LAD, 2.44±1.1cm for CX, and 1.63±2.8cm for RCA). Consequently, FFR and distal RFR values corrected with average pressure differentials rarely yielded different cut-off-based characterizations compared to individually measured corrections (2.4%). A total of 42 measurements were evaluated in Center 1 (33 patients) and 40 measurements in Center 2 (40 patients). Stenoses were characterized using resting Pd/Pa (0.91 ± 0.05), FFR (0.80 ± 0.08), distal RFR (0.86 ± 0.09) and ΔRFR (0.07 ± 0.07) values. Regarding all the investigated vessels, statistically significant differences were observed in FFR (0.80 ± 0.08 vs 0.81 ± 0.08; p &amp;lt; 0.001), distal RFR (0.86 ± 0.09 vs 0.87 ± 0.09; p &amp;lt; 0.001), and ΔRFR (0.053 ± 0.04 vs 0.047 ± 0.04; p = 0.014) before and after correction. These changes after hydrostatic correction were driven dominantly by the LAD measurements being LAD stenoses constituted the majority of the cases (73.2%). Overall (n=82), hydrostatic pressure correction modified cut-off-based categorization in 24 (29.3%) cases for Pd/Pa, and 19 (23.2%) cases for both distal RFR and FFR measurements. Notably, ΔRFR assessment also changed in 22.2% of cases after correction. Among LAD stenoses (n=60), hydrostatic pressure correction altered cut-off-based characterization in 22 (36.7%), 19 (31.7%), and 17 (28.3%) cases of resting Pd/Pa, distal RFR, and FFR measurements, respectively. Hydrostatic pressure correction offers the potential to enhance the accuracy of intracoronary physiological measurements, especially for LAD stenoses. Our data suggest that the published average pressure differences of each coronary segment can be used for correction.Lateral view and delta RFRIndividual vs Average LAd correction

Opportunistic Identification of Coronary Artery Calcium and Valve/Vascular Calcifications on Chest X-Ray: Improvements With Single-Exposure Dual-Energy Imaging.

Purpose: To evaluate whether single-exposure, dual-energy chest X-ray (DEX) improves visualization of coronary artery calcium (CAC) and valve/vascular calcifications compared to conventional X-ray. Materials and Methods: Sixty-one bone-marrow transplant patients (22- 79 years; median 61; IQR 15; w/m, 24/37), underwent single-exposure dual-energy X-ray (Reveal 35C, KA imaging) in pa and lateral projection, followed by a standard-of-care chest CT. Two DEX pairs (pa/lateral) were calculated: a composite image (COMP) and a bone image with soft-tissue subtraction (BI). The COMP pair was reviewed by 2 chest radiologists, assessing the presence/absence of CAC and valve/vascular calcifications on a confidence scale from -2 (confidently not present) to 2 (confidently present). Subsequently, the BI pair was revealed, and readers reevaluated both pairs (COMP and BI) jointly using the identical scale. CTCAC scores were categorized according to the CAC-DRS (0-3) and served as standard of reference, valve/vascular calcifications were categorized on CT as present or absent. Results: For detecting CAC on DEX in any CAC-DRS category (1-3), in category 2-3, in category 3, and for valve/vascular calcifications, the ROC-AUC (combined for both readers) for COMP images was 0.74 (CI: 0.64-0.84), 0.81 (CI: 0.68-0.94), 0.84 (CI: 0.69-0.98), and 0.90 (CI: 0.83-0.99), and for the BI images 0.91 (CI: 0.83-0.98), 0.94 (CI: 0.86- 1.00), 0.89 (CI: 0.77-1.00), and 0.98 (CI: 0.96-1.00), with P = .0003, P = .044, P = .42, and P = .55, respectively. The Intraclass-Correlation-Coefficient (ICC) for CAC on COMP/BI was 0.973/0.954, and for valve/vascular calcifications 0.971/0.965. Conclusion: Single-exposure, dual-energy acquisition improves diagnostic confidence for coronary artery calcium and valve/vascular calcification identification on chest X-rays.

Sex estimation using skull silhouette images from postmortem computed tomography by deep learning.

Prompt personal identification is required during disasters that can result in many casualties. To rapidly estimate sex based on skull structure, this study applied deep learning using two-dimensional silhouette images, obtained from head postmortem computed tomography (PMCT), to enhance the outline shape of the skull. We investigated the process of sex estimation using silhouette images viewed from different angles and majority votes. A total of 264 PMCT cases (132 cases for each sex) were used for transfer learning with two deep-learning models (AlexNet and VGG16). VGG16 exhibited the highest accuracy (89.8%) for lateral projections. The accuracy improved to 91.7% when implementing a majority vote based on the results of multiple projection angles. Moreover, silhouette images can be obtained from simple and popular X-ray imaging in addition to PMCT. Thus, this study demonstrated the feasibility of sex estimation by combining silhouette images with deep learning. The results implied that X-ray images can be used for personal identification.

A 3D imaging system for dosimetry in FLASH radiotherapy

This study examines the feasibility of reconstructing the spatial dose distribution delivered by a 9 MeV electron beam within a plastic scintillator block using optical tomography. The system is designed for use in 3D-dosimetry for clinical applications in quality assurance and beam characterization, especially with FLASH-beam sources. The proposed detector reconstructs the 3D dose distribution map employing a monolith with 10 cm side, imaged in four different projections by scientific cameras. The 3D dose distribution simulated with Geant4 was reconstructed using a maximum likelihood expectation maximization algorithm applied to the lateral projection, resulting in a longitudinal image with a standard deviation of 0.2 Gy. Furthermore, a preliminary experimental test has been performed.

Three-dimensional secondary reconstruction of mistreated zygomatic fractures using patient specific surgical guides and implants.

The zygomatic bone has a great impact on the anterior and lateral projection of the midface as well as the proper position of the globe. Primary alignment of zygomatic fractures is very important as secondary reconstruction is far more challenging. Treatment of misaligned zygoma requires refracturing of the bone to allow for repositioning. Due to the great impact of the zygoma on the projection of the midface, a precise 3D realignment is of great importance. Technology nowadays develops rapidly and allows for superior results in many surgical fields. The use of patient specific surgical guides and fixation plates is becoming more abundant. Using 3D segmentation and design software, we developed a sequence for using 3D planning and printing both for the refracturing stage, avoiding a coronal approach, and for precise repositioning and fixation of the zygoma in the new position. The method is described as well as a unique advanced 3D analysis, allowing for objectively assessing the results. Two cases are presented, including the design and post operative changes. Pre-op, planned and final positions were compared and showed exceptional accuracy allowing for the elimination of human errors which are common in a 3D sensitive procedure such as refracturing of the zygoma. This method can easily be applied to other secondary reconstruction procedures requiring realignment.

A new and widely distributed species of Ichthyurus Westwood, 1848 (Cantharidae, Chauliognathinae, Ichthyurini) from China.

The genus Ichthyurus Westwood, 1848 is a large cantharid group consisting of approximately 200 species worldwide, with only 10 species hitherto found in China. Despite its expansive area, the Chinese fauna has historically received little attention from specialists, leading to a lack of knowledge even about some common Ichthyurus species in this region. A new species of Ichthyurus Westwood, 1848 is described under the name of I.longulus sp. nov., which is widely distributed in mainland China, including Shannxi, Gansu, Hubei, Chongqing, Guizhou and Guangxi. Although there are some variations in the pronotum colouration within the species, this new species could be easily distinguished from all others of Ichthyurus by the large-sized body, uniformly black elytra, mesotibiae each with an apical spur in male, terminal abdominal tergite of male with long and cylindrical lateral projections that are about 3/5 the length of the tergite, terminal abdominal ventrite of male saddle-shaped and deeply cleft in middle of apical 2/3 part and aedeagus with a long setifore extension that is as long as the parameres. The habitus, terminal abdominal ventrite and tergites and genitalia of both sexes are illustrated. In addition, a distribution map of this species and a list of the Ichthyurus species from mainland China are provided.

Standard radiographic images in cephalomedullary nailing fixation for intertrochanteric femoral fractures

To review and summarize the projections of radiographic images during cephalomedullary nailing fixation for intertrochanteric femoral fractures, and to propose a set of three projections as standard requirement in immediate postoperative fluoroscopy. Papers on intertrochanteric femoral fractures treated with cephalomedullary nailing fixation that published in a three-year period of 2021-2023 in four leading English orthopedic trauma journals were searched in PubMed. The presented radiographic pictures were identified and scrutinized as whether they were in standard anteroposterior and/or lateral projections of the implanted nails. The nonstandard presence percentage was calculated. Combined with clinical experience, the standard anteroposterior and lateral perspective images of femoral neck, the current situation of radiographic imaging in the operation of cephalomedullary nails, the literature analysis of nonstandard images, the impact of limb rotation on image interpretation, and the characteristics of anteromedial 30° oblique perspective were summarized and analyzed. The presence of nonstandard radiographic pictures is 32.1% in anteroposterior view and 69.2% in lateral view in leading orthopedic trauma journals. In cephalomedullary nailing fixation operation of intertrochanteric femoral fractures, it is reasonable to use the radiographic images of the implanted nails to represent the fractured head-neck, as the head-neck implant (lag screw or helical blade) is aimed to put into centrally in femoral head in lateral projection. Limb rotation or nonstandard projections produced distortion of images, which interfers the surgeons' judgement of fracture reduction quality and the measurement of implant position parameters in femoral head (such as neck-shaft angle and tip-apex distance), and finally lead to a meaningless comparison with the accurate normal value. The 30° anteromedial oblique view from the true lateral (set as 0°) is a tangential projection of the cortices at the anteromedial inferior corner, which gives a clear profile for the determination of cortical apposition status and mechanical support. It is essential to get firstly the true standard lateral fluoroscopy of the nail (shown as a line), then rotate the C-arm to 90° and 30° to get anteroposterior and anteromedial oblique views, and use these three immediate postoperative radiographies as the baseline for evaluation of operative quality and follow-up comparisons. As for real-time monitoring of surgical steps, intraoperative fluoroscopy follows the "Enough is Good" principle, but as for immediate postoperative data storage and basis for operative quality evaluation and baseline for follow-up comparison, it is recommended to obtain a set of three standard radiographic pictures in anteroposterior, true lateral, and 30° anteromedial oblique fluoroscopic projections.

Radiation dose and image quality optimization in lumbar spine digital radiography for overweight and obese patients: Phantom study

Background: Lumbar spine radiography plays an important role in routine use for clinical practice in overweight and obese patients. The radiographer is responsible for setting suitable exposure factors for the tradeoffs between radiation dose and image quality (IQ). Objective: To investigate the effect of different kVp values combined with AEC used on radiation dose and IQ for routine lumbar spine radiography in overweight and obese patients. Materials and methods: A 1.5 and 3 cm thickness of frozen pork lard was placed on a pelvis phantom to simulate an overweight and obese patient, respectively. The phantom was imaged at 10 kVp intervals in combination with AEC used. For IQ evaluation, CNR and SNR were calculated, and the observer study was determined using visual grading scores (VGS) with a 5-point Likert scale. The radiation dose was measured using a DAP meter, and then the figure of merit (FOM) was calculated. Results: SNR and CNR for both AP and lateral projection showed a slightly decreasing trend when kVp increased in all groups. The DAP values decreased when the higher kVp was selected with AEC used in each group. The VGS by five radiographers showed good image quality in all groups, while the FOM at 100 and 109 kVp was the highest score for both AP and lateral projections. Conclusion: The optimal kVp setting in this study ranged from 100 to 109 kVp in combination with AEC used, indicating minimal radiation dose, while maintaining diagnostic IQ.

The Potential Clinical Utility of an Artificial Intelligence Model for Identification of Vertebral Compression Fractures in Chest Radiographs

PurposeTo assess the ability of the Annalise Enterprise CXR Triage Trauma (Annalise AI Pty Ltd, Sydney, NSW, Australia) artificial intelligence model to identify vertebral compression fractures on chest radiographs and its potential to address undiagnosed osteoporosis and its treatment. Materials and methodsThis retrospective study used a consecutive cohort of 596 chest radiographs from four US hospitals between 2015 and 2021. Each radiograph included both frontal (anteroposterior or posteroanterior) and lateral projections. These radiographs were assessed for the presence of vertebral compression fracture in a consensus manner by up to three thoracic radiologists. The model then performed inference on the cases. A chart review was also performed for the presence of osteoporosis-related International Classification of Diseases, 10th revision diagnostic codes and medication use for the study period and an additional year of follow-up. ResultsThe model successfully completed inference on 595 cases (99.8%); these cases included 272 positive cases and 323 negative cases. The model performed with area under the receiver operating characteristic curve of 0.955 (95% confidence interval [CI]: 0.939-0.968), sensitivity 89.3% (95% CI: 85.7%-92.7%) and specificity 89.2% (95% CI: 85.4%-92.3%). Out of the 236 true-positive cases (ie, correctly identified vertebral compression fractures by the model) with available chart information, only 86 (36.4%) had a diagnosis of vertebral compression fracture and 140 (59.3%) had a diagnosis of either osteoporosis or osteopenia; only 78 (33.1%) were receiving a disease-modifying medication for osteoporosis. ConclusionThe model identified vertebral compression fracture accurately with a sensitivity 89.3% (95% CI: 85.7%-92.7%) and specificity of 89.2% (95% CI: 85.4%-92.3%). Its automated use could help identify patients who have undiagnosed osteoporosis and who may benefit from taking disease-modifying medications.

Patient Factors Influencing Outcomes at 12-Year Follow-up of Hip Arthroscopy for Femoroacetabular Impingement

Background: Arthroscopic treatment of femoroacetabular impingement has increased in popularity since the early 2000s when it was first described, although only a few midterm follow-up studies have been published. Purpose: To describe the outcomes of patients undergoing hip arthroscopy for femoroacetabular impingement at a mean 12-year follow-up and to determine the risk factors for failure. Study Design: Case-control study; Level of evidence, 3. Methods: The Non-Arthritic Hip Score (NAHS) and a radiographic evaluation were completed preoperatively and at midterm follow-up. Participants were divided into 2 groups according to their clinical evolution. The success group consisted of patients whose NAHS at the final follow-up was above the established Patient Acceptable Symptom State (PASS) threshold of 81.9, whereas patients who underwent a second surgical intervention or did not reach the PASS threshold at final follow-up were assigned to the failure group. These groups were compared to identify preoperative differences in demographic, pathological, and surgical factors. Results: A total of 95 hips were included, after 23 were lost to follow-up (80.5% follow-up). At a mean follow-up of 12.1 years (range, 9.2-16.0 years), 9 hips required total hip arthroplasty (9.5%), 5 required revision hip arthroscopy (5.3%), 29 did not achieve the NAHS PASS threshold (30.5%), and 52 achieved the NAHS PASS threshold (54.7%). The mean NAHS was 82.4 at final follow-up compared with 66.9 preoperatively (mean difference = 15.5; P < .001). Higher mean body mass index (24.9 vs 23.0; P = .030), older age (30.0 vs 27.2; P = .035), and inferior preoperative lateral joint space width (3.9 vs 4.4; P = .019) were associated with inferior prognosis in the failure group versus success group. Osteoarthritis progression was observed in 69.2% of the failure group and in 34.8% of the success group (P = .082). Labral ossification was observed in 78.3% of all patients, and its lateral projection length was statistically associated with failure (P = .015). Conclusion: At a mean 12-year follow-up, hip arthroscopy for femoroacetabular impingement led to significant clinical improvement, with 55% PASS achievement. In total, 31% of patients were below the PASS threshold, 5% had revision arthroscopy, and only 9% had conversion to total hip arthroplasty for a 45% global failure rate. Increased body mass index, older age, and smaller preoperative lateral joint space width were significant negative prognostic factors. Postoperative degenerative changes were highly prevalent and demonstrated association with failure.

Lateral inhibition in V1 controls neural & perceptual contrast sensitivity.

Lateral inhibition is a central principle for sensory system function. It is thought to operate by the activation of inhibitory neurons that restrict the spatial spread of sensory excitation. Much work on the role of inhibition in sensory systems has focused on visual cortex; however, the neurons, computations, and mechanisms underlying cortical lateral inhibition remain debated, and its importance for visual perception remains unknown. Here, we tested how lateral inhibition from PV or SST neurons in mouse primary visual cortex (V1) modulates neural and perceptual sensitivity to stimulus contrast. Lateral inhibition from PV neurons reduced neural and perceptual sensitivity to visual contrast in a uniform subtractive manner, whereas lateral inhibition from SST neurons more effectively changed the slope (or gain) of neural and perceptual contrast sensitivity. A neural circuit model identified spatially extensive lateral projections from SST neurons as the key factor, and we confirmed this with anatomy and direct subthreshold measurements of a larger spatial footprint for SST versus PV lateral inhibition. Together, these results define cell-type specific computational roles for lateral inhibition in V1, and establish their unique consequences on sensitivity to contrast, a fundamental aspect of the visual world.

The Importance of Aneurysm Morphology and Perianeurysmal Environment in Aneurysmal Subdural Hematomas

Aim: Aneurysmal subdural hematoma (anSDH) is an uncommon condition associated with significant mortality risk. This study focused on the relationship between morphology and the perianeurysmal environment by comparing aneurysm location and clinical outcomes. Material and Methods: A total of 486 patients with aneurysmal subarachnoid hemorrhage were retrospectively analyzed for accompanying subdural hematoma (SDH) cases. Demographic information, rebleeding, discharge, and 6 months of the modified Rankin scale scores (favorable and unfavorable) were recorded. The aneurysms were divided into 3 groups: internal carotid artery (ICA), anterior cerebral artery (ACA), and middle cerebral artery (MCA). Other parameters included aneurysm morphology, SDH width, intracerebral hematoma (ICH) volume, the presence of intraventricular hematoma, and distance to the subdural space. Results: Concomitant SDH was detected in 19 (3.9%) patients. Aneurysms were located in the ICA, 10 (52.6%); MCA, 8 (42.1%); and ACA, one (5.3%). The mean size was 9.5±4.3 mm, and there was a significant difference in aneurysm size between the ICA and MCA (p=0.025). In six supraclinoid aneurysms (posterior communicating and anterior choroidal arteries), the aneurysm dome was in the inferior lateral projection. No significant differences were observed between patients with favorable and unfavorable modified Rankin scale in terms of clinical and aneurysm morphological characteristics, except for increased ICH volume (p=0.020) and shift effects (p=0.030). Conclusion: The size and dome projection of ICA supraclinoid segment aneurysms may be important risk factors for SDH. We also believe that aneurysm localization may have a limited impact on clinical outcomes in the context of SDH.

Influence of anatomical structure on antiscatter grid performance in 2D: application to x-ray angiography and a prototype 29:1 ratio grid

Objective. The use of uniform phantoms to assess the influence of x-ray scatter and antiscatter grids on x-ray angiography and fluoroscopy image quality disregards the influence of spatially variable x-ray attenuation of patients. The purpose of this work was to measure scatter to primary ratio (SPR) and antiscatter grid SNR improvement factor (K SNR) using experimental conditions which better mimic patient imaging conditions. Approach. Three adult-sized anthropomorphic phantoms were used. AP and lateral projection images of the thorax and abdomen were acquired with and without an antiscatter grid. Grids with ratio 15:1 and 29:1 (r15, r29) and x-ray fields of view 20, 25 (thorax) and 32, 42 cm (abdomen) were tested. Combined with a-priori measurements of grid scatter and primary transmission fractions, these images were used to calculate 2D SPR and K SNR maps. Main results. Results demonstrated that measurements by uniform phantom do not describe the complex 2D SPR and K SNR distributions associated with anthropomorphic phantoms. The regions of the images with the lowest primary x-ray intensity (greatest attenuation) had the highest SPR and the highest K SNR attributable to the grids. Considering all conditions, the 95th percentile of the SPR maps was in the range 42%–185% greater than the median values and that of the K SNR maps was 4%–20% higher than the median values. The combined influences of SID 120 vs. 107 cm and r29 vs. r15 grid resulted in K SNR in the range 1.05–1.49. Significance. Performance of anti-scatter grids using anatomically complex phantoms highlights the substantial variation of SPR and K SNR within 2D images. Also, this work demonstrates the benefit of the prototype r29 grid for thoracic and abdominal angiography imaging conditions is substantial, especially for large patients and radiodense image regions.

Radiographic characterization of the maxillary septum and septal bullae in horses: An ex vivo study.

The anatomical variations of the maxillary septum and the septal bullae can generate challenges during the interpretation of radiographs of the horses' heads and make it difficult to accurately identify the sites affected in sinus disorders. The description of the radiographic appearance of these structures is currently scarce in the scientific literature. This work aims to describe the anatomical and radiographic characteristics of the maxillary septum and maxillary septal bullae in horses. Six chemically preserved equine cadaver heads were used which, after being submitted to the maxillary osseous flap, the maxillary septum and its respective bullae were identified. Radiographic examinations before and after contrast impregnation on these structures were performed. The positioning of the maxillary septum varied between the anatomical specimens and between the sides of the same specimen. The 30° oblique dorsoventral lateral and lateral projections allowed the identification of the maxillary septum and septal bullae. However, the bullae remained superimposed on the dental arches in the dorsoventral projections with the mandible in a neutral position or with the mandible displaced. The oblique offset radiographic positioning was suggested and proved effective for the examination of the maxillary septal bullae, where the mandible was displaced to the side of the bullae to be examined, and the radiographic beam inclined in the same direction. The maxillary septum and its bullae could be properly identified in a macroscopic way after the osseous flap and the contrasted radiographic examination allowed its adequate interpretation. Variations in size and position are considered normal for the equine species.

Assessment of the Relationship between Antero-Posterior Dental Malocclusions, Body Posture Abnormalities and Selected Static Foot Parameters in Adults.

Objectives: This study aimed to find if a relationship exists between antero-posterior malocclusions and the level of musculoskeletal disorders in adults, including body posture and static foot analysis. Methods: In all, 420 participants were recruited through convenience sampling (Kraków University students and patients of a local dentist's practice). Following general medical interviews, dental examinations and consideration of inclusion and exclusion criteria, 90 healthy volunteers (ages 19-35) were enrolled and assigned to three groups (n = 30) based on occlusion type (Angle's molar Class I, II or III). The research procedure involved occlusion and temporomandibular disorder assessment conducted by a dental specialist. Comprehensive morphological measurements of body asymmetry were performed using the Videography 2D package and FreeSTEP software, which calculated the parameters determined from anterior, posterior and lateral projection photos. Foot loading distribution was analyzed using the FreeMED baropodometric platform. Results: Significant differences were demonstrated in the positioning of the head, cervical and lumbar spine in the sagittal plane among individuals with the analyzed occlusal classes (p < 0.05). Individuals with Angle's Class II exhibited significantly greater forward head positions and greater depths of cervical and lumbar lordosis compared with individuals with Class III or Class I. Those with overbites had higher forefoot loading. The Class III individuals exhibited greater L-R displacement, indicating a larger angle of displacement of the centers of the right and left feet relative to the lower edge of the measurement platform, suggesting pelvic rotation. Conclusions: An inclination for concurrent occurrences of malocclusions and posture deviations in the sagittal plane was observed. An interdisciplinary approach involving dentistry and physiotherapy specialists which utilizes tools for comprehensive posture assessment is crucial for diagnosing and treating such conditions.

X-ray diagnostics diseases of the temporomandibular joints

TMJ diseases, the occurrence of which can be caused by numerous factors, are a common pathology among the population. The purpose of the study was to research the characteristics of x-ray manifestations and the informativeness of x-ray techniques in the x-ray diagnosis of TMJ diseases. 645 X-ray images of 344 patients aged 18 to 65 years were analyzed. It has been established that the X-ray picture of most TMJ diseases is characterized by the presence of functional changes or a combination of functional and organic manifestations. The most common pathology is dysfunctional disorders of the TMJ. It was concluded that the primary X-ray diagnosis of TMJ diseases is advisable to carry out using orthopantomographs, which allow examining the TMJ in the lateral projection according to a special program with the patient’s mouth open and closed. The use of computed tomography makes it possible to identify not only functional abnormalities, but also early manifestations of organic changes in the bone elements of the TMJ on a series of tomographic sections in different planes.

Bone mineral density and geometric morphometrics: Indicators of growth in the immature pars basilaris

The pars basilaris forms a central component of the immature basicranium and owing to its resilience to post-mortem and taphonomic changes, holds significance across evolutionary, clinical, and forensic contexts. While size and shape parameters of the pars basilaris have been investigated, little is known about the influence of the underlying bone mineral density on the morphometry of this bone during growth. This study aimed to investigate the development and growth of the pars basilaris with specific reference to changes in bone density patterning and development of osteological features, during the prenatal and early postnatal periods of life. A total of 109 pars basilari were sourced from the Johannesburg Forensic Paediatric Collection, University of the Witwatersrand, South Africa. The study sample was subdivided into early prenatal (<30 gestational weeks), prenatal (30–40 gestational weeks) and postnatal (birth to 7.5 months) groups and micro-CT scanned to assess bone mineral density patterns across seven regions of interest. Size and shape changes were analysed using 11 digitized landmarks and geometric morphometrics. When comparing across age groups, the assessed dimensions increased with growth manifesting as a deepening at the anterior border of the foramen magnum, development of the lateral angles and widening of the bone at the lateral projections and spheno-occipital synchondrosis. However, no significant changes in the distribution of bone mineral density were observed. An appreciation of morphological changes and bone quality at specific growth sites in the pars basilaris is essential when analyzing remains of unknown provenance for the purposes of identification in disaster victim settings.