Multidetector Computed Tomography Research Articles

Usefulness of a novel density measurement drill for evaluating cancellous bone density: correlation between CT value and drilling torque value in bovine ribs

PurposeThe study aimed to examine the usefulness of a novel density measurement drill for evaluating cancellous bone density by examining the correlation between computed tomography (CT)-based Misch bone density classification and drilling torque value.MethodsBovine ribs were used as the drilling sites for implant placement. Multidetector CT (MDCT) was performed after contrast materials were attached to the drilling sites. CT value within the region of interest (ROI) on MDCT scan was measured and classified according to the Misch classification (D1 to D5). Drilling torque value was measured using a novel measurement drill. Next, histomorphometric analysis of the drilling site was performed to assess bone density, expressed as percentage of bone area within ROI.ResultsMDCT showed the presence of D2 (n = 87), D3 (n = 92), D4 (n = 133), and D5 (n = 52) at the measurement sites, however, no sites were classified as D1. The drilling torque values were 11.2 ± 3.2 Ncm for D2, 7.8 ± 3.3 Ncm for D3, and 3.0 ± 1.2 Ncm for D4, and 1.4 ± 0.6 Ncm for D5, with significant differences. A positive correlation was observed between CT value and drilling torque value (r = 0.99). Histomorphometric analysis revealed a positive correlation between drilling torque value and bone area ratio (r = 0.97).ConclusionsThe results of this limited study demonstrated the usefulness of the direct and objective cancellous bone density evaluation method using a novel measurement drill. This evaluation method will be informative for subsequent treatment decisions.

Anatomical Predictors of Access-Related Vascular Complications Following Transfemoral Transcatheter Aortic Valve Replacement.

Access-related vascular complications (VCs) after percutaneous transfemoral transcatheter aortic valve replacement (TAVR) are associated with poor clinical outcomes and remain a significant challenge despite technological advances. The aim of this study was to identify anatomic predictors of access-related VCs after TAVR on preprocedural contrast-enhanced multidetector computed tomography (MDCT). The aim of this study was to identify anatomical predictors of access-related VCs after TAVR on preprocedural contrast-enhanced MDCT. A total of 348 consecutive patients with symptomatic severe AS who underwent transfemoral TAVR were included retrospectively. The primary endpoint of the study was the composite of minor and major access site complications as defined by the Valve Academic Research Consortium-3 (VARC-3) criteria. The study population was divided into two groups according to the VC including VC (+) and VC (-). A total of 101 patients (29%) developed VC (8.7% major, 20.3% minor) following TAVR. Regression analysis identified severe CFA calcification (p = 0.004), CFA depth (p < 0.001), minimum CFA diameter (p < 0.001), CFA depth-to-diameter ratio ≥ 5.6 (p < 0.001), and sheath-to-femoral artery ratio (SFAR) (p < 0.001) as significant predictors of VC. ROC curves generated for the occurrence of VC, the AUC for the femoral artery depth-to-diameter ratio (0.720) was higher than the AUC for the SFAR and the depth of the femoral artery (0.636, 0.630). Complications related to vascular access sites continue to be a significant concern for patients undergoing TF-TAVR. The CFA depth-to-diameter ratio has demonstrated superior predictive performance for VC compared to SFAR as expressed in the literature. Utilizing this criterion may enhance risk stratification for VC in high-risk patients, potentially reducing associated morbidity and mortality.

High-resolution 0.25mm Detector CT Has Limited Impact on Right Adrenal Vein Detectability in Preprocedural Contrast Enhanced CT for Adrenal Venous Sampling.

This study aims to identify factors associated with the detectability of the right adrenal vein (RAV) on preoperative contrast-enhanced CT scans of adrenal venous sampling (AVS) in the era of high-resolution CT (HRCT). In this retrospective study, 36 patients (15 men and 21 women; mean age, 56y) who underwent preoperative contrast-enhanced CT [11 patients in HRCT with 0.25mm detector matrix (Cannon Medical Systems) and 25 patients in conventional multidetector CT with 0.5mm matrix] were included. A contrast agent dose of 600mgI/kg was injected, and CT images were acquired at a fixed scan delay of 50 and 80 seconds. Adrenal venography and venous sampling were performed for the diagnosis of suspected primary hyperaldosteronism. The qualitative detectability of RAV on preoperative CT was assessed with adrenal venography as a reference. Clinical and imaging factors associated with a good detectability of RAV were analyzed via regression analysis. Optimal acquisition timing was assessed by analyzing the time-intensity curve and contrast enhancement pattern of the inferior vena cava using CT data from a separate cohort (n=5). The qualitative detectability of RAV was deemed good in 15 patients and poor in 21 patients. Regression analysis revealed that only heterogeneous enhancement of inferior vena cava with bolus high attenuation, corresponding to an optimal acquisition timing from time-intensity curve analysis, was associated with a good detectability of RAV (odds ratio, 5.06). The use of HRCT was not statistically significant. Optimal acquisition timing is a crucial factor for the detectability of RAV in preprocedural CT for AVS, while high-resolution 0.25 detector CT appears to have limited significance.

Estimation of sex based on pelvic girdle measurements in a Jordanian population: a computed tomographic study

ABSTRACT Sex estimation from skeletal measurements that display sexual dimorphism is fundamental in forensic anthropology. Our aim was to establish population-specific discriminant equations for predicting sex from pelvic girdle measurements in a contemporary Jordanian population using 3D multidetector computed tomography (MDCT). A total of 302 pelvic MDCT scans (144 males and 158 females) were used and a total of 16 linear measurements and two angles were studied. Discriminant function analysis (DFA) was used to evaluate the possibility of sex categorization. All measurements were sexually dimorphic, except pubic length and maximum breadth of sacral alae (p ≥ 0.05). The multivariate analysis yielded an accuracy rate of 97.4% and a sex bias of −0.3%. Subpubic angle, angle of greater sciatic notch, innominate height, transverse pelvic inlet and ischial length were selected by stepwise analysis as best discriminators of sex, with an accuracy rate of 98.0% and a sex bias of −0.2%. Subpubic angle was the best single pelvic parameter in sex estimation with an accuracy of 88.1%. Lower classification accuracies and higher sex bias were obtained using univariate analysis. Considering multiple pelvic girdle measurements simultaneously, CT scans of living Jordanians provides a reliable source of osteometric data from which DFA equations can be derived.

Beyond the Surface: A Multidetector Computer Tomography Scan Investigation into Age and Gender Differences.

Background The identification of an individual after mass calamities poses challenges to experts when bones are fragmented. Dense bones, such as the maxilla, surpass this challenge and remain intact with sinuses even after incineration, thereby making the sinuses an ideal and reliable forensic science tool. No-ninvasive imaging techniques, such as Computed Tomography (CT), can be used to evaluate such cases and help detect fractures and further locate foreign bodies. This study aimed to estimate the dimensions and volumes of the frontal (FS), maxillary (MS), and sphenoidal air sinuses (SS) on CT scans and investigate age- and sex-related differences. Methods CT scans of the paranasal sinuses were acquired from 158 patients ranging in age from 19 to 73 years, and written consent was obtained from all participants. This study was approved by the Institutional Ethical Committee (ethical clearance number IEC 064/2010). All parameters were statistically analyzed using SPSS 20 version and the significance level was set at p&lt;0.05. Results The bilateral anteroposterior length and height of the FS were significantly larger in men than females (p&lt;0.05). The overall dimensions of the MS and SS were substantially greater in males than females (P &lt;0.05). Likewise, the overall volumes of the fFS, MS, and SS were significantly greater in males than females (p&lt;0.05). However, no significant age-related correlation was observed in the dimensions and volumes of the sinuses. Conclusion The results of this study showed that imaging could be a reliable instrument for personal identification in forensic anthropology. Countries that do not allow autopsies may implement this method to clarify the cause of death.

Visualization of Right Adrenal Vein in Non-Contrast-Enhanced MDCT and Its Guiding Role for Right Adrenal Venous Sampling.

This study aimed to evaluate the visualization of right adrenal vein (RAV) in non-contrast-enhanced multi-detector computed tomography (MDCT) and its guiding role for right adrenal venous sampling (AVS) in patients with primary aldosteronism (PA). A total of 237 patients diagnosed with PA who underwent successful AVS procedures from January 2020 to March 2021 were retrospectively analyzed. The non-contrast-enhanced MDCT image features of RAV included the degree of visualization and the position of RAV orifice. Subsequently, the concordance degree between RAV in non-contrast-enhanced MDCT and AVS images was calculated to evaluate its guiding effect for right AVS. The visualization rate of RAV in non-contrast-enhanced MDCT was 81.9% (n=194), with 73.7% (n=143) clearly displayed and 26.3% (n=51) generally displayed. In 6.2% (n=12) of patients who can display RAV, RAV formed a common trunk with the accessory hepatic vein and then merged into the inferior vena cava. Non-contrast-enhanced MDCT revealed that RAV orifice was located between the 10th thoracic vertebra (T10) and the 1st lumbar vertebra (L1), with 85.1% (n=165) located from the lower 1/3 of T11 to the lower 1/3 of T12. The concordance of imaging anatomy of RAV between non-contrast-enhanced MDCT and AVS image was found to be at a high rate of 94.3% (n=183). Non-contrast-enhanced MDCT provides excellent visualization of RAV and clearly depicts its anatomical characteristics. Furthermore, RAV images obtained from non-contrast-enhanced MDCT are highly consistent with those from AVS, indicating that interpretation of non-contrast-enhanced MDCT before AVS can reduce the failure rate of RAV cannulation.

Evaluation of Root Canal Diameters and Radicular Wall Thickness of the Human Primary Molars by using Multidetector Computed Tomography: A Cross-sectional Study

Introduction: Paediatric endodontics is critical for preserving the primary tooth until its physiologic exfoliation and ensuring the child’s quality of life. Endodontic treatment of human primary molars with varying internal geometry of the root canal necessitates extensive knowledge and skills. Aim: To evaluate the diameters of the root canals and the radicular wall thickness of human primary molars using Multidetector Computed Tomography (MDCT). Materials and Methods: This cross-sectional study study was performed in the Department of Paediatric and Preventive Dentistry in collaboration with the Department of Oral and Maxillofacial Surgery, Department of Antaomy of Guru Nanak Institute, Kolkata, West Bengal,India on selected 64 human primary maxillary and mandibular molars through inclusion and exclusion criteria and grouped them (Group 1, maxillary 1st molars; Group 2, maxillary 2nd molars; Group 3, mandibular 1st molars; and Group 4, mandibular 2nd molars). After proper sterilisation, the teeth were mounted on a wax platform, and the mounted teeth block was scanned by a computed tomography scanner. Analysis of these Computed Tomography (CT) scan images was done through Denta Scan (GE Healthcare, USA) software. In each of the corresponding cross-sections, the diameters of the root and the root canals were measured at their greatest diameter. The radicular wall thickness of the roots was derived by subtracting the measured diameter of the root canals from that of the roots in their respective cross-sections. Descriptive statistical analysis (Student’s t-test) was performed. A p-value less than equal to 0.05 was considered statistically significant. Results: The maximum mean diameter of the canal was found in the mesiobuccal root canal of both primary mandibular first molars (1.16±0.22 mm at cervical third) and second molars (1.12±0.16 mm at cervical third); and the minimum diameter was found in the distolingual root canal of both primary mandibular first molars (0.87±0.12 mm at cervical third) and second molars (0.89±0.16 mm at cervical third). The mean radicular wall thickness of the roots gradually increased from the apical third to the cervical third of both primary molars. Conclusion: The maximum root canal diameter and radicular wall thickness were found in the cervical third of the palatal root of maxillary second molars. The study evaluates the mean maximum and minimum diameters of each canal of human primary molars and radicular wall thickness in different crosssections, which enables paediatric dental practitioners to establish effective paediatric endodontic treatment.

Qualitative and Quantitative Evaluation of the Image Quality of MDCT Multiphasic Liver Scans in HCC Patients.

Background: The quality of CT images obtained from hepatocellular carcinoma (HCC) patients is complex, affecting diagnostic accuracy, precision, and radiation dose assessment due to increased exposure risks. Objectives: The study evaluated image quality qualitatively and quantitatively by comparing quality levels with an effective radiation dose to ensure acceptable quality accuracy. Materials and Methods: This study retrospectively reviewed 100 known HCC patients (Li-RADS-5) who underwent multidetector computed tomography (MDCT) multiphasic scans for follow-up of their health condition between January and October 2023. The evaluation involved quantitative and qualitative analyses of parameters such as SD, SNR, and CNR, as well as a qualitative assessment by two radiology consultants. The outcomes were compared, and the effective dose was calculated and compared with both quantitative and qualitative assessments of image quality. Results: ROC curve analysis revealed significant differences in CT image quality, with high to moderate specificity and sensitivity across all the quantitative parameters. However, multivariate examination revealed decreasing importance levels, except for CNR (B, 0.203; p = 0.001) and SD BG (B, 0.330; p = 0.002), which increased in B. The CNR and SD BG remained independent variables for CT image quality prediction, but no statistically significant relationship was found between the effective dose and image quality, either quantitatively or qualitatively. Conclusion: This study underscores the vital role of both quantitative and qualitative assessments of CT images in evaluating their quality for patients with HCC and highlights the predictive importance of CNR, SNR, and SD. These findings emphasize the value of these devices in assessing and predicting outcomes to minimize the effective dose.

ECG-Gated Cardiac Multidetector CT Evaluation of the Normal Pulmonary Valve and Right Ventricular Outflow Tract in Dogs.

With the advancement in imaging technology, ECG-gated cardiac multidetector computed tomography (MDCT) has emerged as a tool for the anatomic evaluation of the pulmonary valve and right ventricular outflow tract (RVOT) in human medicine. Currently, the evaluation of the pulmonary valve relies primarily on echocardiographic examination. However, the bi-dimensional nature of this technique and the location/orientation of the pulmonary valve in the thoracic cavity can pose challenges. In human medicine, ECG-gated MDCT distinguishes four main anatomic components of the pulmonary valve and RVOT: the pulmonary valve leaflets, the sinotubular junction, the anatomic ventriculo-arterial junction and the hemodynamic ventriculo-arterial junction. Hence, this study aimed to describe the computed tomographic findings of the normal RVOT and pulmonary cusps in a population of dogs. This is an anatomic prospective descriptive study. A total of 24 dogs underwent a complete echocardiographic examination and an ECG-gated MDCT to rule out pulmonary valve abnormalities. Multiplanar reconstruction of the pulmonary valve was obtained. Additionally, hearts from three dogs euthanized for reasons unrelated to the study were collected and their gross and histological findings were compared with the CT images. The ECG-gated MDCT provided good visualization of the pulmonary valve leaflets, the sinotubular junction, the anatomic ventriculo-arterial junction and the hemodynamic ventriculo-arterial junction. Notably, the short-axis view of the pulmonary valve anatomy resembled the 'Mercedes-Benz sign' characteristic of the aortic valve in all dogs. In conclusion, this study provides the first description of the CT anatomy of the RVOT in dogs without pulmonary valve and RVOT abnormalities.

Preprocedural imaging guiding ventricular tachycardia ablation in structural heart disease.

Integration of preprocedural imaging techniques in ventricular tachycardia (VT) ablation may improve the identification of arrhythmogenic substrates, particularly relevant for patients with nonischemic cardiomyopathy (NICM) with sub-optimal outcomes. We assessed the impact of advanced preprocedural imaging on the safety and long-term efficacy of radiofrequency catheter ablation (RCA) for VT, comparing patients with NICM and ischemic cardiomyopathy (ICM). In this prospective, single-center study, consecutive patients referred for scar-related VT ablation underwent multidetector computed tomography (MDCT) and late gadolinium enhancement cardiac magnetic resonance (LGE-CMR). Images were segmented with ADAS 3D software and integrated into mapping systems. Substrate map collection targeted the imaging-predicted area of interest and the ablation aimed at eliminating all local abnormal ventricular activities. Procedural safety was evaluated with 30-day mortality. Long-term efficacy was assessed by survival free from appropriate ICD shocks at 36 months. 102 patients were included (67 ± 11 years, 94% male; 75 ICM, 27 NICM). All patients underwent MDCT and 35% also underwent LGE-CMR. Procedural safety (4% 30-day mortality, p = .95) and 36-month efficacy were similar in both groups (88.0% vs. 74.1%, HR 2.09; p = .13 in ICM and NICM). Efficacy was higher in patients when VT activation mapping with VT isthmus ablation complemented substrate ablation compared to substrate-based ablation alone (94.5% vs. 80.6%, HR 4.00; p < .05). A preprocedural imaging protocol integrated into the invasive mapping system may improve safety and long-term efficacy, with NICM patients exhibiting outcomes comparable to those with ICM. Activation mapping of the VT on top of substrate ablation may improve prognosis.

Accuracy of the Hounsfield Unit Values Measured by Implant Planning Software.

Background: The measurement of Hounsfield units (HU) during implant treatment planning is important. Currently, various manufacturers' implant planning software programs offer HU capabilities; however, their accuracy remains unverified. In this study, we aimed to validate the accuracy of HU values measured by implant planning software programs. Methods: This study used one type of multidetector computed tomography (MDCT), two types of cone-beam computed tomography (CBCT), and four implant planning software packages. Three specimens were prepared for the evaluation of HUs, and the standard values of the HUs were measured. Digital Imaging and Communications in Medicine (DICOM) data obtained from MDCT and CBCT were loaded into four implant planning software packages to measure the HU values. The HU and reference values of the four implant planning software programs obtained from MDCT and CBCT were compared. Additionally, the HU values between each implant planning software program were compared. Results: The HU values of the three specimens, as measured using the four implant planning software programs utilizing MDCT, did not exhibit a significant difference from the standard values. Conversely, those obtained from CBCT were significantly different. The measured HU values after the MDCT imaging of the specimens were not significantly different between the implant planning software programs; however, they differed after CBCT imaging. Conclusions: The results of this study indicate that it is not possible to measure HU values using CBCT with implant planning software programs. However, HU values can be measured by any implant planning software using MDCT.

Precision of Intraoperative Cone-Beam Computed Tomography in Electrode Placement and Complications in Asleep Deep Brain Stimulation Surgery: A Multidetector Computed Tomography-Verified Comparative Study.

Successful deep brain stimulation (DBS) requires precise electrode placement. However, brain shift from loss of cerebrospinal fluid or pneumocephalus still affects aim accuracy. Multidetector computed tomography (MDCT) provides absolute spatial sensitivity, and intraoperative cone-beam computed tomography (iCBCT) has become increasingly used in DBS procedures. However, its accuracy is unclear. We examined iCBCT accuracy and the need for postoperative imaging to confirm electrode position and assess complications of DBS surgery. Thirty-two movement disorder patients, and 69 targets were retrospectively reviewed. All patients had preoperative non-stereotactic 3.0 Tesla magnetic resonance imaging (MRI), preoperative stereotactic MDCT, post-implantation iCBCT, and postoperative conventional MDCT scans. Stereotactic coordinates of electrode tips were compared between postoperative MDCT and iCBCT. We calculated the absolute and Euclidian differences (ED) between iCBCT and postoperative MDCT coordinates for each electrode. To assess whether intraoperative brain shifting influenced electrode tip localisation, subdural pneumocephalus volume was measured in iCBCT images. The mean absolute (scalar) differences in x, y, and z coordinates were not significantly different from the absolute precision value of 0 (p 0.05). The mean ED between the iCBCT electrode tip and the postoperative MDCT electrode tip coordinates was 1mm (0.55±0.03 mm) and differed significantly from zero (p 0.0001). There was no correlation between pneumocephalus volume and electrode coordinate deviation. iCBCT can eliminate the need for routine postoperative studies since it is a safe, effective, and rapid procedure that can be performed at any step of the surgery. It provides reliable and definitive confirmation of correct DBS electrode placement.

Estimation of population affinity using cranial measurements acquired in multidetector computed tomography images of Japanese and Malay individuals.

It is imperative in a forensic investigation to determine the identity of an unidentified corpse, for which a crucial starting point is to establish population affinity as part of the biological profile supplied by the forensic anthropologist. The present study investigates the feasibility of using multidetector computed tomography (MDCT) images to quantify craniometric variation between Japanese and Malay populations relative to the estimation of population affinity in a forensic context. The Japanese and Malay samples comprise MDCT scans of 252 (122 female; 130 male) and 182 (84 female; 98 male) adult individuals, respectively. A total of 18 measurements were acquired, and two machine learning methods (random forest modeling, RFM; support vector machine, SVM) were applied to classify population affinity. The accuracy of the two-way pooled-sex model was 88.0% for RFM and 94.5% for SVM, respectively. The four-way population and sex model produced an overall classification accuracy of 81.3% for RFM and 91.7% for SVM. The sex-specific models of population affinity showed correct rates of classification of more than 90% in both females (90.8% for RFM and 97.6% for SVM) and males (91.2% for RFM and 97.4% for SVM). Our findings clearly indicate that the cranial measurements acquired in MDCT images can be used for the forensic classification of Japanese and Malay individuals and thus serve as a reference for forensic anthropologists attempting to identify unidentified remains.

Comparison of sequential multi-detector CT and cone-beam CT perfusion maps in 39 subjects with anterior circulation acute ischemic stroke due to a large vessel occlusion.

The critical time between stroke onset and treatment was targeted for reduction by integrating physiological imaging into the angiography suite, potentially improving clinical outcomes. The evaluation was conducted to compare C-Arm cone beam CT perfusion (CBCTP) with multi-detector CT perfusion (MDCTP) in patients with acute ischemic stroke (AIS). Thirty-nine patients with anterior circulation AIS underwent both MDCTP and CBCTP. Imaging results were compared using an in-house algorithm for CBCTP map generation and RAPID for post-processing. Blinded neuroradiologists assessed images for quality, diagnostic utility, and treatment decision support, with non-inferiority analysis (two one-sided tests for equivalence) and inter-reviewer consistency (Cohen's kappa). The mean time from MDCTP to angiography suite arrival was , and that from arrival to the first CBCTP image was . Stroke diagnosis accuracies were 96% [93%, 97%] with MDCTP and 91% [90%, 93%] with CBCTP. Cohen's kappa between observers was 0.86 for MDCTP and 0.90 for CBCTP, showing excellent inter-reader consistency. CBCTP's scores for diagnostic utility, mismatch pattern detection, and treatment decisions were noninferior to MDCTP scores (alpha = 0.05) within 20% of the range. MDCTP was slightly superior for image quality and artifact score (1.8 versus 2.3, ). In this small paper, CBCTP was noninferior to MDCTP, potentially saving nearly an hour per patient if they went directly to the angiography suite upon hospital arrival.

Sex determination method using the third cervical vertebral body by head and neck CT.

This study aimed to measure the volume of the third cervical vertebra using head and neck multi-detector computed tomography (MDCT) and establish a sex determination model based on sex differences in volume. Head and neck CT images of 85 patients were obtained for dental diagnostic and therapeutic purposes. Digital Imaging and Communications in Medicine (DICOM) data obtained from head and neck CT were constructed using a three-dimensional image analysis software. A region of interest was created that included the entire third cervical vertebra and its volume was measured. Descriptive statistics were calculated for the measurements, and the means, standard deviations, and medians of the measurements were calculated separately for men and women. To create a sex determination model, binomial logistic regression analysis was performed using the training data group, with vertebral volume and sex as the explanatory and objective variables, respectively. The mean score of men was significantly higher than that of women. The sex determination model using the volume of the third cervical vertebral body resulted in an 80% correct sex classification rate. The sex determination model can be used with other regional methods to aid sex determination.

Thermal Liquid Biopsy: A Promising Tool for the Differential Diagnosis of Pancreatic Cystic Lesions and Malignancy Detection.

Pancreatic cystic lesions (PCLs) are a heterogeneous group of lesions with increasing incidence, usually identified incidentally on imaging studies (multidetector computed tomography (MDCT), magnetic resonance imaging (MRI), or endoscopic ultrasound (EUS)) [...].

Evaluation of bismuth shielding in reducing thyroid radiation dose during neck multidetector computed tomography examinations: a comparative study

Objectives: This study pointed to assess the viability of bismuth protecting in lessening thyroid radiation measurements amid neck multidetector computed tomography (MDCT) examinations and to explore alternative protecting strategies which will moderate negative impacts on picture quality. Methods: The study involved 20 patients undergoing neck MDCT. Thermoluminescent dosimeters (TLDs) were utilized to degree radiation measurements to the thyroid organ with and without bismuth protecting. Measurable investigations, counting combined tests t-test and Wilcoxon signed-rank test, were conducted to evaluate the importance of dosage decrease. Results: Bismuth protecting altogether diminished the radiation measurements to the thyroid organ by 43.95%, from 24.50 mGy to 17.59 mGy (P&amp;lt;0.01). The reduction was statistically significant in women (P&amp;lt;0.01) but not in men (P&amp;gt;0.05) due to the small sample size. No significant correlation was found between age and radiation dose levels (P&amp;gt;0.05). Conclusions: Bismuth shielding effectively reduces thyroid radiation dose during neck MDCT examinations. However, the potential increase in image noise necessitates careful management to maintain diagnostic accuracy. Further research is needed to optimize shielding techniques and explore alternative methods to minimize radiation exposure while preserving image quality.

Volumetric analysis of maxillary sinus and assessment of various sinonasal anatomic variants on multi-detector computed tomography (MDCT) and their association with chronic rhinosinusitis.

The study aimed to evaluate the relationship between maxillary sinus volume and various sinonasal anatomical variants, as detected by multi-detector computed tomography, and their associations with chronic rhinosinusitis (CRS). A case-control study was conducted with 103 patients presenting with chronic sinonasal symptoms (cases) and 50 asymptomatic individuals (controls). A 128-slice computed tomography scanner was used to measure maxillary sinus volume and assess anatomical variants, such as a deviated nasal septum (DNS), concha bullosa (CB), and agger nasi cells. Exclusion criteria included previous sinonasal surgery, malignancy, craniofacial trauma, and lack of consent. Statistical analysis was performed using t-tests for continuous variables and Chi-square tests for categorical data. Receiver operating characteristic curve analysis was utilized to determine a DNS angle cutoff for predicting CRS. Anatomical variants were significantly more frequent in cases than in controls. The left-sided DNS was predominant in cases, while the right-sided DNS was more common in controls. The mean DNS deviation angle was notably larger in cases (10.84° ± 7.87) than in controls (5.55° ± 5.02). Maxillary sinus volume was significantly smaller in cases (9.69 cc on the left side and 10.23 cc on the right side) compared to controls (18.57 cc and 18.46 cc, respectively), with female patients exhibiting smaller volumes than males. Agger nasi cells were detected in 51.5% of cases versus 8.0% of controls. A strong association was found between CB and contralateral DNS. The optimal DNS deviation angle cutoff for predicting CRS was identified as 12.7°. This study shows that CRS is linked to smaller maxillary sinus volumes, with males having larger sinus volumes than females. A DNS and larger deviation angles were associated with a higher risk of sinus inflammation, with angles over 12.7° predicting the onset of the condition. The presence of CB and agger nasi cells also contributed to the development of CRS.

New Perspectives in the Etiology of Chronic Rhinosinusitis-Haller Cells.

Background and Objectives: Haller Cells (HCs) represent the abnormal migration of ethmoid cells that are located below the ethmoid bulla at the level of the upper wall of the maxillary sinus. Through their placement, the cells can exert a mass effect on the infundibulum of the maxillary sinus. The aim of our study is to investigate the prevalence of Haller cells in the Romanian population and to evaluate the relationship between this anatomical variation and chronic rhinosinusitis. Secondly, we want to morphometrically evaluate the impact of Haller cells' presence in the drainage paths of the maxillary sinuses. Materials and Methods: We conducted a randomised retrospective study that included 255 consecutive multi-detector computed tomography (MDCT) scans of the head. To carry out a comparative evaluation of the association of Haller cells with chronic rhinosinusitis, we divided the patients into two subgroups, a seasonal-based sample, between November 2022 and January 2023, and June 2023 and August 2023, respectively. We report the mean ± standard deviation for the continuous variables. To compare the results, we used the following statistical tests: a chi-squared test and a paired Student's t-test (one-tail). Results: Our study identified a high prevalence of Haller cells, namely in 128 out of 255 patients (50.2%). There were no statistically significant associations between the presence of HCs and the age and the gender of the sample, respectively. The unilocular morphotype predominates in unilateral shapes and in bilateral shapes as well (p = 0.002). Our study identified the correlation between the Haller cells and the chronic rhinosinusitis in both research samples: "Winter group" and "Summer group" (p = 0.0002 and p = 0.0001, respectively). Conclusions: It was determined that for 40 out of 42 patients, the presence of HCs changes the morphometric pattern of the infundibular maxillary sinus.

Visualization of anatomical structures in the carpal region of the horse using cone beam computed tomography in comparison with conventional multidetector computed tomography.

In the diagnostics of orthopedic diseases in the horse, diagnostic imaging often plays a decisive role. Cone beam computed tomography (CBCT) imaging is used in both human and small animal medicine and becoming increasingly popular. To see whether CBCT imaging can be useful in the diagnosis of orthopedic diseases of the carpal region of the horse and to explore possible limitations we compared CBCT images with multidetector computed tomography (MDCT) images of the carpal region of equine cadaveric specimens. Twenty-eight forelimbs from fifteen horses, slaughtered for reasons unrelated to this study, were examined. Native and contrast enhanced CBCT and MDCT scans were performed. Anatomical structures were blindly evaluated by three independent experienced observers using a visual scoring system previously reported and adapted to the equine carpal region. A descriptive evaluation was carried out as well as Spearman's rank correlation and interobserver agreement was shown by percent agreement (PA). Visualization of osseous structures was excellent in both MDCT and CBCT. Articular cartilage could only be assessed in contrast enhanced scans whereby MDCT showed a slightly better visualization than CBCT. Soft tissue structures were generally difficult to assess. An exception were the medial and lateral palmar intercarpal ligament, which could not be visualized in native but were well visualized in contrast enhanced scans in both MDCT and CBCT images. For the evaluation of osseous structures and some intraarticular ligaments after contrast enhancement, CBCT serves as a reliable diagnostic imaging modality for the equine carpal region. However, soft tissue structures and cartilage are imaged more reliably using MDCT.