Multidetector Computed Tomography Scans Research Articles

Patterns of collateral arteries to the spinal cord after thoraco-abdominal aortic aneurysm repair.

Our goal was to evaluate postoperative patterns of collateral arteries to the spinal cord during occlusion of the segmental arteries supplying the artery of Adamkiewicz (AKA). Between April 2011 and December 2022, a total of 179 patients underwent thoraco-abdominal aortic aneurysm repair; 141 had an identifiable AKA on preoperative multidetector computed tomography scans, 40 underwent thoraco-abdominal aortic aneurysm replacement (TAAR) and 101 underwent thoracic endovascular aortic repair (TEVAR). New postoperative collateral blood pathways invisible on preoperative contrast-enhanced computed tomography scans were identified in 42 patients (10 patients who had TAAR vs 32 patients who had TEVAR) who underwent preoperative and postoperative multidetector computed tomography scanning for AKA identification. The thoracodorsal and segmental arteries were the main collateral pathways in both groups. Th9-initiated collaterals were the most common. Collaterals from the internal thoracic artery were observed in the TEVAR group but not in the TAAR group. One patient in the TEVAR group experienced postoperative paraparesis, which was not observed in the TAAR group. Postoperative paraplegia was more common in the non-Th9-origin group, but this difference was not significant. Thoracodorsal and segmental arteries may be important collateral pathways after TEVAR and TAAR. For thoracodorsal arteries, preserving the thoracodorsal muscle during the approach would be crucial; for segmental arteries, minimizing the area to be replaced or covered would be paramount. An AKA not initiated at the Th9 level poses a high risk of postoperative paraplegia.

Artificial Intelligence-Based Non-invasive Differentiation of Distinct Histologic Subtypes of Renal Tumors With Multiphasic Multidetector Computed Tomography.

With rising cases of renal cell carcinoma (RCC), precise identification of tumor subtypes is essential, particularly for detecting small, heterogenous lesions often overlooked in traditional histopathological examinations. This study demonstrates the non-invasive use of deep learning for Histopathological differentiation of renal tumors through quadriphasic multidetector computed tomography (MDCT). This prospective longitudinal study includes 50 subjects (32 males, 18 females) with suspected renal tumors. A deep neural network (DNN) is developed to predict RCC subtypes using peak attenuation values measured in Hounsfield Units (HUs) obtained from quadriphasic MDCT scans. The network then generates confidence scores for each of the four primary subtypes of renal tumors, effectively distinguishing between benign oncocytoma and various malignant subtypes. Our neural network accurately distinguishes Renal tumor subtypes, including clear cell, papillary, chromophobe, and benign oncocytoma, with a confidence score of 68% with the network's diagnosis aligning with Histopathological examinations. Our network was also able to accurately classify RCC subtypes on a synthetically generated dataset with 20,000 samples. We developed an artificial intelligence-based RCC subtype classification technique. Our approach is non-invasive and has the potential to transform the methodology in Renal oncology by providing accurate and timely diagnostic information and enhancing clinical decisions.

Comparison of Conventional Radiography and Multidetector Computed Tomography Scan in Knee Trauma in Rajavithi Hospital

Objective: This study aimed to compare the diagnostic results and agreement among XR, MDCT, and combined examination between XR and MDCT in diagnosing knee bone fractures.
 Methods: A retrospective was conducted of 243 patients who experienced knee trauma and underwent both XR and MDCT scans between January 1, 2016, and January 1, 2021, at Rajavithi Hospital in Bangkok, Thailand.
 Results: Out of the 243 patients, 147 were male (60.5%), and 96 were female (39.5%), with 226 (93%) displaying fractures. MDCT identified a total of 319 fractures in various anatomic regions. Computed tomography scans compared with the two combined methods showed no difference in results. However, the radiography results were significantly different compared to the two methods combined (p<0.05). MDCT+XR proved more effective in diagnosing fractures than XR alone. The agreement between MDCT versus MDCT+XR exceeded 0.98, whereas the agreement between XR versus MDCT+XR was less than 0.9, except for femoral fractures (0.935). Overall, utilizing both MDCT and XR together significantly enhanced the diagnostic effectiveness compared to using XR alone.
 Conclusion: MDCT imaging provides more accurate results, while XR imaging is still valuable for certain fractures. The combined methods were more accurate, especially in cases where the fracture type and characteristics cannot be determined with XR alone. The high level of agreement between XR and MDCT supports the combined use of both methods in clinical practice for diagnosing knee injuries.

Steatotic liver disease and its newly proposed sub-classifications correlate with progression of the coronary artery calcium score.

A new nomenclature, Steatotic Liver Disease (SLD), has been proposed by consensus with sub-classifications and requires evidence-based validation. We assessed whether the presence and severity of SLD, as well as its sub-classifications, are associated with the progression of coronary atherosclerosis. This longitudinal cohort study included 13,811 adults who participated in repeated regular health screening examinations between January 1, 2004 and December 31, 2021 that included assessments of their coronary artery calcium (CAC) scores. SLD was defined using abdominal ultrasonography and classified as metabolic dysfunction associated steatotic liver disease (MASLD), MASLD with increased alcohol intake (MetALD), and cryptogenic SLD. SLD severity was assessed using fibrosis-4 (FIB-4) scores. The progression of CAC scores was measured using multidetector CT scans. The average duration of follow-up was 5.8 years. During follow-up, the annual rate of CAC progression in participants with and without SLD was 18% (95% CI 17%-19%) and 14% (95% CI 13%-14%) (p < 0.01), respectively. The multivariable ratios of progression rates when we compared participants with cryptogenic SLD, MASLD, or MetALD with those without SLD were 0.98 (95% CI 0.95-1.01), 1.03 (95% CI 1.03-1.04), and 1.07 (95% CI 1.04-1.09), respectively. The multivariable ratios of progression rates when we compared participants with SLD with FIB-4 score <1.3 and SLD with FIB-4 score ≥1.3 with those without SLD were 1.03 (95% CI 1.02-1.04), and 1.05 (95% CI 1.04-1.06), respectively. SLD was associated with a higher risk of coronary atherosclerosis, and the risk differed by sub-classifications and severity. These findings suggest that the newly proposed definition has clinical relevance in terms of stratifying cardiovascular disease risk.

A morphological study of the inferior phrenic arteries on multidetector computed tomography and angiography

IntroductionThe inferior phrenic artery is a paired artery with a variable origin and course, primarily supplying the diaphragm, but also the suprarenal glands, inferior vena cava, stomach, and oesophagus. The aim of this study is to investigate the origin and course of the inferior phrenic arteries on multidetector computed tomography and angiography. Materials and methodsThe anatomy of the inferior phrenic artery was analysed on 2449 multidetector computed tomography scans. Three-dimensional reconstructions were made of the main variations. Additionally, the course and branching pattern of the inferior phrenic artery were descriptively analysed in a cohort of 28 angiograms. ResultsIn 565 (23.1%) cases the inferior phrenic arteries arose as a common trunk and in 1884 (76.9%) cases as individual vessels. The most common origins of a common trunk were the coeliac trunk (n=303; 53.6%) and abdominal aorta (n=255; 45.1%). The most common origins of the right inferior phrenic artery were the coeliac trunk (n=965; 51.2%), abdominal aorta (n=562; 29.8%) and renal arteries (n=214; 11.4%). The most common origins of the left inferior phrenic artery were the coeliac trunk (n=1293; 68.6%) and abdominal aorta (n=403; 21.4%). ConclusionThe inferior phrenic artery has a very variable anatomy. The most common origins of the inferior phrenic artery are the coeliac trunk and its branches, the abdominal aorta, and the renal arteries.

Ocular biometry in rabbits using computed tomography.

To describe a repeatable method of measuring ocular structures and to establish ocular biometry reference ranges in adult domestic rabbits (Oryctolagus cuniculus) without medical history or imaging findings consistent with ophthalmic disease using a 64-slice multidetector computed tomography scanner. In this retrospective and observational anatomic study, 100 eyes from 50 rabbits without medical history or imaging findings consistent with ophthalmic disease who received a head computed tomography scan were selected for measurement of globe length, width, and height using 3D multiplanar reconstruction. Lens width and length, the anteroposterior length of the anterior and vitreous chambers, and attenuation of the lens and vitreous chamber were collected. These parameters were compared against age, sex, weight, body condition, and ear conformation. A reference guide was established, with globe width being the largest dimension (18.03 ± 0.81 mm), followed by height (17.18 ± 0.69 mm) and then length (16.64 ± 0.66 mm). Increased weight was associated with an increase in globe height (p = 2.43 × 10-5 ), length (p = 1.63 × 10-4 ), and width (p = 7.0 × 10-3 ). Increased age was associated with increased lens attenuation (p = 1.28 × 10-7 ) and increased transverse lens width (p = 1.64 × 10-3 ). Inter- and intra-observer agreement was excellent. CT is a reliable modality for measurement of ocular biometry dimensions in rabbits. These reference values can be applied to aid in identifying diseases that affect the dimensions of the ocular structures in rabbits over 18 months of age.

Determination of Sex of an Individual by Frontal Sinus Using Multidetector Computed Tomography Scan: A Retrospective Forensic Study

Abstract Objectives An important aspect of forensic investigation is determining the sex of an unidentified person. The frontal sinus is unique and remains intact, thus making it suitable for forensic analysis. The main objective of this study is to determine the sex of an individual by frontal sinus using a multidetector computed tomography scan. Materials and Methods A total of 100 patients (50 males and 50 females) were included in the study, and different parameters of the frontal sinus for both sides were analyzed, that is height, width, depth, and total length. Statistical Analysis Descriptive statistics of all the variables were computed and compared. SPSS version 16 was used to perform the Mann–Whitney U test, binary logistic regression, and receiver operating characteristic (ROC) curve analysis on the acquired data. Results The result suggested that males have higher mean values than females, with the left frontal sinus height being the only variable to be statistically significant (p &lt; 0.05). Based on the ROC curve analysis, the optimum cutoff value was 0.489, which means if the predicted probability value was less than 0.489, the individual was considered a male; and if the predicted probability value was ≥0.489, the individual was considered a female. The accuracy of the mathematical model based on binary logistic regression analysis for determining sex was 70% for females and 66% for males. Conclusions The present study plays a significant role in determining sex in the Indian population by using left frontal sinus height measurement through a multidetector computed tomography scan.

Objective image quality assurance in cone-beam CT: Test methods, analysis, and workflow in longitudinal studies.

Standards for image quality evaluation in multi-detector CT (MDCT) and cone-beam CT (CBCT) are evolving to keep pace with technological advances. A clear need is emerging for methods that facilitate rigorous quality assurance (QA) with up-to-date metrology and streamlined workflow suitable to a range of MDCT and CBCT systems. To evaluate the feasibility and workflow associated with image quality (IQ) assessment in longitudinal studies for MDCT and CBCT with a single test phantom and semiautomated analysis of objective, quantitative IQ metrology. A test phantom (CorgiTM Phantom, The Phantom Lab, Greenwich, New York, USA) was used in monthly IQ testing over the course of 1 year for three MDCT scanners (one of which presented helical and volumetric scan modes) and four CBCT scanners. Semiautomated software analyzed image uniformity, linearity, contrast, noise, contrast-to-noise ratio (CNR), 3D noise-power spectrum (NPS), modulation transfer function (MTF) in axial and oblique directions, and cone-beam artifact magnitude. The workflow was evaluated using methods adapted from systems/industrial engineering, including value stream process modeling (VSPM), standard work layout (SWL), and standard work control charts (SWCT) to quantify and optimize test methodology in routine practice. The completeness and consistency of DICOM data from each system was also evaluated. Quantitative IQ metrology provided valuable insight in longitudinal quality assurance (QA), with metrics such as NPS and MTF providing insight on root cause for various forms of system failure-for example, detector calibration and geometric calibration. Monthly constancy testing showed variations in IQ test metrics owing to system performance as well as phantom setup and provided initial estimates of upper and lower control limits appropriate to QA action levels. Rigorous evaluation of QA workflow identified methods to reduce total cycle time to ∼10min for each system-viz., use of a single phantom configuration appropriate to all scanners and Head or Body scan protocols. Numerous gaps in the completeness and consistency of DICOM data were observed for CBCT systems. An IQ phantom and test methodology was found to be suitable to QA of MDCT and CBCT systems with streamlined workflow appropriate to busy clinical settings.

Exploring the Complex Interplay: Fatty Liver Severity, Epicardial Fat Volume, and Coronary Artery Calcification

Background and Objective: Cardiovascular diseases and nonalcoholic fatty liver disease are the most common non-communicable diseases in most developed countries, and due to lifestyle changes, their incidence is increasing day by day. The present study aimed to assess the correlation of fatty liver with epicardial fat volume and coronary artery calcium score. Materials and Methods: This cross-sectional study was conducted on 136 patients referred to Hamadan Farshchian Cardiovascular Hospital for computed tomography (CT) angiography. They were selected using a consecutive sampling method. Using a 128-slice multidetector CT scanner, the coronary artery calcium score based on the Agatston criteria and epicardial fat volume were measured. A liver ultrasound was performed using a GE voluson E6 and a 3-5 MHz depth probe, and the severity of the fatty liver was determined based on the echogenicity of the liver on the ultrasound. Data analysis was conducted using the SPSS software (version 26). Results: The mean age scores of patients were 52.90±12.10 years. Regarding gender, 50.5% and 49.5% of cases were male and female, respectively. In terms of fatty liver grade, 64 (47.1%), 48 (35.3%), 21 (15.4%), and 3 (2.2%) cases had grades zero, I, II, and III, respectively. The mean calcium score was 30.76±35.40, and epicardial fat volume was 86.84±36.56. The severity of fatty liver demonstrated no significant relationship with calcium score and epicardial fat (P&gt;0.05). Conclusion: As evidenced by the obtained results, the severity of fatty liver had no relationship with the amount of coronary epicardial fat and coronary artery calcium.

Utility of CT Scan in Detecting Bladder Involvement Among Patients With Cervical Carcinoma.

Background Cervical cancer is a widespread health issue in India, particularly affecting women as the second most common cancer. The burden of cervical cancer in the country necessitates accurate staging for treatment optimization. The revised International Federation of Gynecology and Obstetrics (FIGO) staging system is vital for this purpose, emphasizing the extent of parametrial and pelvic sidewall involvement. Cervical cancer's propensity to infiltrate neighboring pelvic organs, including the bladder, necessitates precise staging. In India, traditional methods like cystoscopy have been relied upon, but they have limitations. Recent advancements in medical imaging, notably the increased use of computed tomography (CT) scans, provide a non-invasive alternative for staging and evaluating bladder involvement. This study aimed to evaluate the utility and accuracy of CT scans in assessing bladder involvement. Methods This cross-sectional study examined 127 newly diagnosed cervical carcinoma cases in women over a two-year period from August 2021 to July 2023. Patients underwent CT scans (plain) and cystoscopy, and bladder involvement was determined following the revised FIGO staging. Data collected comprised patient demographics, medical history, clinical symptoms, and FIGO staging. Cystoscopy was performed using an Olympus CYF-5 flexible cystoscope, and CT scans utilized a 64-slice multidetector CT scanner. Radiological reports detailed primary tumor characteristics and proximity to the bladder. Statistical analysis encompassed descriptive statistics, and calculation of sensitivity, specificity, positive predictive value, and negative predictive value for CT scans in comparison to cystoscopy. Statistical significance was considered at p < 0.05. Results In our study, the mean participant age was 45.3 years, with 61.4% falling in the 40-60 years age group. Socioeconomic status (SES) varied, with 37.8% classified as low SES, 48.8% as middle SES, and 13.4% as high SES. Parity data showed that 76.4% had three or more pregnancies. Among presenting symptoms, abnormal vaginal bleeding (65.4%) was the most prevalent, and squamous cell carcinoma (78.7%) was the predominant histological type. The prevalence of bladder involvement was 9.4% by cystoscopy and 30.7% by CT scans. CT scan demonstrated a high sensitivity (100%) but lower specificity (76.52%), with 78.80% overall accuracy. Conclusion A combined approach, using CT scans as a screening tool and cystoscopy as a confirmatory method, could provide the most comprehensive and reliable assessment of bladder involvement in cervical carcinoma patients, ultimately contributing to improved patient care and management.

Ultrasonography, computed tomography and magnetic resonance imaging of the dromedary camel distal limbs

BackgroundLameness associated with the distal limb region in dromedary camels is quiet prevalent. The diagnosis of lameness relies on a comprehensive orthopedic examination conjugated with an appropriate imaging modality to achieve a decisive diagnosis. Using of modern imaging tools provoked a significant breakthrough in the diagnosis of lameness. Ultrasonography (US) is widely established in dromedaries, whereas computed tomography (CT) and magnetic resonance imaging (MRI) are gaining popularity. CT provides a considerably higher bone detail than any other imaging modality. US and MRI continue to be the best options for soft tissue imaging. A truthful assessment of the clinical US, CT and MRI images dictates a comprehensive familiarity with the standard US, CT and MRI tissue deviations. Accordingly, our purposes were to present a full MRI protocol for investigating the dromedary camel distal limbs as well as comparing and illustrating the merits of using MRI, CT and US for evaluation of the front and hind distal limbs in 10 healthy lameness free dromedary camel cadavers. The limbs were scanned via a high-field 1.5 Tesla MRI magnet and a multi-detector CT scanner then subjected to a systematic US examination in both longitudinal and transverse planes. The obtained MRI, CT and US images were evaluated, correlated and compared.ResultsCT and MRI eliminated the structural superimposition in the dromedary camel distal limbs and afforded assessment of minute ligamentous and tendentious structures that were inaccessible by US including the axial collateral ligaments, ligaments supporting the proximal sesamoid bones and the palmar/plantar aspects of the inter-phalangeal joints. US and MRI were appreciated for the assessment of the articular cartilage that was not visible on the plain CT images.ConclusionsCT and MRI accurately identified and characterized bones and soft tissues constituting the dromedary camel distal limbs. US was appreciated for assessment of soft tissues, articular cartilage and bone contours. CT and MRI may be considered when US results are inconclusive or to evaluate the unreachable parts of the camel distal limbs. Images presented in this study could be used as a reference standard for evaluating dromedary camel distal limb diseases.

Evaluation of diagnostic accuracy of cone beam computed tomography and multi-detector computed tomography for detection of anatomical variations in rhinoplasty

BackgroundDifferent imaging techniques, such as multi-detector computed tomography (MDCT) scan and cone beam computed tomography(CBCT), are used to check the structure of the nose before rhinoplasty. This study aimed to evaluate the accuracy of two imaging techniques, MDCT scan, and CBCT, in diagnosing structural Variations in rhinoplasty for the first time.MethodsThis diagnostic accuracy study was conducted on 64 rhinoplasty candidates who complained of snoring and sleep apnea or had a positive result in the examination with Cottle’s maneuver or modified Cottle technique between February 2021 and October 2022 at 15- Khordad Hospital affiliated to Beheshti University of Medical Sciences. Before rhinoplasty, patients were randomly assigned to one of the CT and CBCT techniques with an equal ratio. Scans were assessed for the presence of Nasal septum deviation (NSD), Mucocele, Concha bullosa, and nasal septal spur by two independent radiologists. The findings of the two methods were evaluated with the results during rhinoplasty as the gold standard.ResultsNSD was the most common anatomical variation based on both imaging techniques. The accuracy of CBCT for diagnosing Nasal Septum Deviation and Mucocele was 80% and 75%, respectively. The sensitivity, specificity, and accuracy of CBCT in detecting Concha bullosa were 81.3% and 83.3%, respectively. The Kappa coefficient between CBCT and intraoperative findings for diagnosing NSD and Concha Bullosa was 0.76 and 0.73, respectively (p < 0.05).ConclusionCBCT can be considered a suitable method with high accuracy and quality to evaluate the anatomical variations before rhinoplasty.

Altered blood flow due to larger aortic diameters in patients with transcatheter heart valve thrombosis.

The etiology of transcatheter heart valve thrombosis (THVT) and the relevance of the aortic root geometry on the occurrence of THVT are largely unknown. The first aim of this pilot study is to identify differences in aortic root geometry between THVT patients and patients without THVT after transcatheter aortic valve implantation (TAVI). Second, we aim to investigate how the observed difference in aortic diameters affects the aortic flow using idealized computational geometric models. Aortic dimension was assessed using pre-TAVI multi-detector computed tomography scans of eight patients with clinical apparent THVT and 16 unaffected patients (two for each THVT patient with same valve type and size) from the Bern-TAVI registry. Among patients with THVT the right coronary artery height was lower (-40%), and sinotubular junction (STJ) and ascending aorta (AAo) diameters tended to be larger (9% and 14%, respectively) compared to the unaffected patients. Fluid-structure interaction (FSI) in two idealized aortic models with the observed differences in STJ and AAo diameter showed higher backflow rate at the STJ (+16%), lower velocity magnitudes in the sinus (-5%), and higher systolic turbulent dissipation rate in the AAo (+8%) in the model with larger STJ and AAo diameters. This pilot study suggests a direct effect of the aortic dimensions on clinically apparent THVT. The FSI study indicates that larger STJ and AAo diameters potentially favor thrombus formation by increased backflow rate and reduced wash-out efficiency of the sinus. The reported observations require clinical validation but could potentially help identifying patients at risk for THVT.

Abstract 13212: Prevention of Delayed Coronary Obstruction Following Transcatheter Aortic Valve Replacement Using Intravascular Ultrasound and "Modified" Snorkeling Stent Technique

Introduction: Coronary obstruction (CO) is a potentially fatal complication that can occur after transcatheter aortic valve replacement (TAVR). Here we report a successful management of a TAVR patient at risk of delayed CO using intravascular ultrasound (IVUS) and a "modified" snorkeling stent technique. Case presentation: An 88-year-old woman presented with severe symptomatic aortic stenosis. Despite the left coronary artery (LCA) being not low, a Multidetector Computed Tomography scan identified a relatively long leaflet of the left coronary cusp (LCC) and a calcified nodule on the cusp (Figure 1A), indicating a high CO risk. A transfemoral TAVR was conducted using a 26mm Evolut FX (Medtronic, IL, USA) protecting the LCA with a 6-F Judkins left (JL) 4.0 guiding catheter, a 0.014 inch coronary guide wire, and a guide-extension catheter. Upon reaching the point of no recapture, LCA blood flow was maintained, and hemodynamics was stable. However, IVUS revealed the calcified nodule on the LCC was close to the left main (LM) ostium (Figure 1B), indicating a high risk of delayed CO.We continued and completed the prosthesis deployment protecting the LCA. Following the deployment, We introduced another guiding catheter (6-F JL3.5) into the prosthesis and engaged it with the LCA via the prosthesis frame, utilizing a double-guiding catheter technique. Subsequently, we placed a coronary stent from the LM to the prosthesis (Figure 1C). After the TAVR procedure, we verified that a JL3.5 catheter could easily engage the implanted coronary stent (Figure 1F). This "modified" snorkeling stent technique appears feasible and provides easier coronary access compared to the "Chimney" snorkeling stent technique.

Determinants of device success after transcatheter aortic valve replacement in patients with type-0 bicuspid aortic stenosis.

Clinical evidence of transcatheter aortic valve replacement in patients with type-0 bicuspid aortic valve was relatively scarce. Our goal was to explore determinants of device success after transcatheter aortic valve replacement in patients with type-0 bicuspid aortic valve morphology. In this retrospective multicenter analysis, we included 59 patients with symptomatic severe aortic stenosis with type-0 bicuspid aortic valve morphology who underwent transcatheter aortic valve replacement. Type-0 bicuspid aortic valve was identified with multidetector computed tomography scans. The technical success rate was 89.8%, and the device success rate was 81.4%. Patients were divided into a device success group and a device failure group according to Valve Academic Research Consortium- 3 criteria. When we compared the two groups, we found that the ellipticity index of the aortic root and the presence of bulky calcifications at the commissure were statistically different (ellipticity index 35.7 ± 1.7 vs. 29.7 ± 1.1, p = 0.018; bulky calcification at the commissure, 54.5% vs. 4.5%, p < 0.001). Further multivariate logistic analysis showed that bulky calcification at the commissure had a negative correlation with device success (odds ratio 0.030, 95% confidence interval 0.003-0.285, p = 0.002). Yet there was no statistical correlation between the ellipticity index and device success (odds ratio 0.818, 95% confidence interval 0.667-1.003, p = 0.053). The presence of bulky calcifications at the commissure is negatively correlated with device success after transcatheter aortic valve replacement in patients with type-0 bicuspid aortic valve.

Assessment of CBCT gray value in different regions-of-interest and fields-of-view compared to Hounsfield unit.

Different factors can affect the discrepancy between the gray value (GV) measurements obtained from CBCT and the Hounsfield unit (HU) derived from multidetector CT (MDCT), which is considered the gold-standard density scale. This study aimed to explore the impact of region of interest (ROI) location and field of view (FOV) size on the difference between these two scales as a potential source of error. Three phantoms, each consisting of a water-filled plastic bin containing a dry dentate human skull, were prepared. CBCT scans were conducted using the NewTom VGi evo system, while MDCT scans were performed using Philips system. Three different FOV sizes (8 × 8 cm, 8 × 12 cm, and 12 × 15 cm) were used, and the GVs obtained from eight distinct ROIs were compared with the HUs from the MDCT scans. The ROIs included dental and bony regions within the anterior and posterior areas of both jaws. Statistical analyses were performed using SPSS v. 26. The GVs derived from CBCT images were significantly influenced by both ROI location and FOV size (p < 0.05 for both factors). Following the comparison between GVs and HUs, the anterior mandibular bone ROI represented the minimum error, while the posterior mandibular teeth exhibited the maximum error. Moreover, the 8 × 8 cm and 12 × 15 cm FOVs resulted in the lowest and highest degrees of GV error, respectively. The ROI location and the FOV size can significantly affect the GVs obtained from CBCT images. It is not recommended to use the GV scale within the posterior mandibular teeth region due to the potential for error. Additionally, selecting smaller FOV sizes, such as 8 × 8 cm, can provide GVs closer to the gold-standard numbers.

Multi Detector Computed Tomography and Ultrasound Evaluation of Neck Masses with Pathological Correlation

Introduction: Neck imaging has always been a diagnostic challenge. High-resolution sonography being inexpensive and safe has become the initial investigation of choice for neck pathologies; it provides information regarding the origin and extent of the lesion. Computed tomography (CT) has a unique capacity for displaying soft tissue, bone and airway details and provides critical anatomical information about lesions involving the neck. This study aims to determine the role of USG and CT in neck masses for pre-operative characterization based on location, extent, morphological characteristics and enhancement pattern and to compare USG and CT findings with histopathological diagnosis.&#x0D; Material and Methods: A total number of 60 adult patients with suspected neck masses were studied in the department of Radiodiagnosis, SSIMS&amp;RC, Davanagere and inputs from Dr. B. R. Ambedkar Medical College, Bengaluru over a period of 24 months. Ultrasound was done using GE Voluson E6 machine &amp; Contrast enhanced CT was done using GE Revolution Multidetector CT scan machine. Post processing techniques (like volume rendered techniques) were applied wherever useful.&#x0D; Results: The findings on USG and CT were conclusive in nearly 90% of cases. Enhancement patterns and presence/absence of bony invasion were found to be more specific in differentiating benign/malignant nature.&#x0D; Conclusion: High-resolution sonography can be used as the first-line modality for evaluating cervical soft tissue masses, it helps the clinicians to characterize the lesion. Multi-detector computed tomography is a sensitive diagnostic tool for diagnosing neck masses and differentiating between benign and malignant lesions with high accuracy. The extent of pathology with local/ contiguous spread predicted by CT examination was conclusive. The overall findings suggest that MDCT and Ultrasound, when used in conjunction with pathological correlation, can be effective tools for accurately characterizing and diagnosing the neck masses.

Three-Dimensional Volume Rendering in Computed Tomography for Evaluation of the Temporomandibular Joint in Dogs.

Based on computed tomography (CT) images, volume rendering was used to obtain a three-dimensional representation of data (3DVR). The aims of this study included: describing the bone anatomy of the temporomandibular joint (TMJ) of dogs; comparing the TMJs of each dog by skull type and age; comparing 3DVR images with three-standard-plane CTs; assessing soft tissues adjacent to the TMJ and assessing pathological cases. Multidetector computed tomography scans of bilateral TMJs of 410 dogs were observed. From a ventral view, slight displacements in the positions of the skulls were seen, whereas from a caudal view, differences in amplitude of the articular space were observed. Dolichocephalic and mesaticephalic dogs showed more similar TMJ features than brachycephalic dogs. The shape of the TMJ bones were irregular in dogs under 1 year old. The 3DVR images related to the three-standard-plane CT improved the overall comprehension of the changes in the articular space amplitude and condylar process morphology. The fovea pterygoidea, mandibular fossa and retroarticular process were perfectly shown. A better spatial situation of adjacent soft tissues was obtained. The 3DVR represents an ancillary method to the standard-plane CT that could help in the understanding of the anatomy and diagnoses of different pathologies of the TMJ in dogs.

Accuracy of Multi-Detector Computed Tomography In the Diagnoses of Adnexal Masses

Background: Ovarian cancer is the 5th common cause of death in women. patients older than 30 years are high malignant potential group. The lifetime risk of dying from invasive ovarian cancer is about 1 in 95. Modern imaging techniques have demonstrated significant accuracy in the diagnosis and staging of adnexal masses that help the clinician in surgical and post-surgical treatment planning. Objective: To determine the accuracy of multidetector computed tomography (MDCT) in diagnoses of benign and malignant adnexal masses, compare it with histopathological diagnoses and find out the sensitivity, specificity, positive predictive value, negative predictive value of MDCT in diagnoses of benign and malignant adnexal masses. Materials and Methods: This cross-sectional observational study was carried out between January 2013 to December 2014 with 45 patients referred for an MDCT scan of the pelvic organ with a suspicion of adnexal mass in Dhaka Medical College, Dhaka. All the patients were evaluated by detailed history and clinical examination. CT scan of the pelvic organ was performed in all cases and the report was checked by the radiologists of DMCH. Operated patients were followed up after surgery up to histopathological diagnosis and correlated with CT scan findings. Results: CT diagnosis for evaluation of benign adnexal mass, sensitivity was 90.0%, specificity 92.0%, accuracy 91.1%, PPV was 90.0% and NPV 92.0%. In the case of malignant mass, sensitivity is 92.0%, specificity 90.0%, accuracy 91.1%, PPV 92.0% and NPV 90.0%. Conclusion: MDCT is a valuable modality in the diagnosis of benign and malignant adnexal masses.KYAMC Journal Vol. 14, No. 02, July 2023: 74-78.

Are multi-detector computed tomography and cone-beam computed tomography exams and software accurate to measure the upper airway? A systematic review.

Cone-beam computed tomography (CBCT) has several applications in various fields of dental medicine such as diagnosis and treatment planning. When compared to computed tomography (CT), CBCT's radiation exposure dose is decreased by 3%-20%. However, CBCT produces more scattered signals and may present poorer image quality when compared to medical CT. To review the findings regarding the accuracy of multi-detector computed tomography (MDCT) and CBCT and to compare the different software programs that segment the upper airway. Three databases (PubMed, Medline, and Web of Science) were searched for articles and a manual search was performed. The inclusion criteria were defined following the PICO framework: P-any patient with a CBCT or CT; I-dimensional evaluation of the upper airway using MDCT or CBCT; C-phantoms; O-the primary outcome was MDCT and CBCT accuracy, the secondary outcome was the evaluation and comparison of software programs used to segment the upper airway. Articles that met eligibility criteria were assessed using the Critical Appraisal Skills Program Checklist. Among the 16 eligible studies, 6 articles referred to the accuracy of MDCTs or CBCTs and 10 to the accuracy of the software. Most articles were qualified as high quality. MDCT and CBCT scans' accuracy in upper airway dimensional measurements depends on machine brand, parameters, and segmentation technique. Regarding the segmentation technique, 12 programs were studied. Most either underestimated or overestimated upper airway measurements. In particular, OnDemand3D and INVIVO showed poor accuracy. On the contrary, Invesalius, and MIMICS were accurate in assessing nasal cavities when using an interactive threshold. However, results varied due to methodological differences among the studies. Finally, fully automatic segmentation based on artificial intelligence may represent the future of airway segmentation because it is faster and seems to be accurate. However, further studies are necessary. This study was registered in Prospero (International Prospective Register of Systematic Reviews) with the ID number CRD42022373998.