Multidetector Computed Tomography Imaging Research Articles

A three-dimensional reconstructive study of pelvic cavity in the red fox (Vulpes vulpes).

Three-dimensional (3D) reconstructive techniques are being used in many morphometric studies and clinical applications. The red fox is a wild animal localized in a wide geography. This study has been performed to determine morphometric properties of the pelvic cavity and reveal differences between sexes via 3D reconstruction obtained by multi-detector computed tomography images (MDCT) of the red fox. A total of 12 adult red foxes of both sexes were used in this study. Two-dimensional (2D) MDCT images of the pelvic cavity obtained and stored in DICOM format were used to reconstruct the 3D model. Mimics 13.1 program was used to perform the 3D reconstruction. A total of 24 dimensions were measured from the reconstructive model of the pelvic cavity. Twenty two dimensions were found to be significantly different (p<0.05) between sexes. In conclusion, according to the pelvimetric data, it was determined that the red fox has sexual dimorphism and these data may be useful in wild animals morphological and gynaecological research. The authors hope to help in the diagnosis and treatment of the pelvic cavity-related orthopaedic and gynaecological disorders in the wild animals.

Generation of Vertebra Micro-CT-like Image from MDCT: A Deep-Learning-Based Image Enhancement Approach.

This paper proposes a deep-learning-based image enhancement approach that can generate high-resolution micro-CT-like images from multidetector computed tomography (MDCT). A total of 12,500 MDCT and micro-CT image pairs were obtained from 25 vertebral specimens. Then, a pix2pixHD model was trained and evaluated using the structural similarity index measure (SSIM) and Fréchet inception distance (FID). We performed subjective assessments of the micro-CT-like images based on five aspects. Micro-CT and micro-CT-like image-derived trabecular bone microstructures were compared, and the underlying correlations were analyzed. The results showed that the pix2pixHD method (SSIM, 0.804 ± 0.037 and FID, 43.598 ± 9.108) outperformed the two control methods (pix2pix and CRN) in enhancing MDCT images (p < 0.05). According to the subjective assessment, the pix2pixHD-derived micro-CT-like images showed no significant difference from the micro-CT images in terms of contrast and shadow (p > 0.05) but demonstrated slightly lower noise, sharpness and trabecular bone texture (p < 0.05). Compared with the trabecular microstructure parameters of micro-CT images, those of pix2pixHD-derived micro-CT-like images showed no significant differences in bone volume fraction (BV/TV) (p > 0.05) and significant correlations in trabecular thickness (Tb.Th) and trabecular spacing (Tb.Sp) (Tb.Th, R = 0.90, p < 0.05; Tb.Sp, R = 0.88, p < 0.05). The proposed method can enhance the resolution of MDCT and obtain micro-CT-like images, which may provide new diagnostic criteria and a predictive basis for osteoporosis and related fractures.

Prevalence and Relevance of Multiple Renal Arteries: A Radioanatomical Perspective.

Background: A single renal artery supplies the kidney in 70% of the population but variation exists in the remaining 30%. Multiple renal arteries (MRA) in different permutations and combinations are one of the many forms of variants. Lack of awareness of multiplicity could have detrimental effects on the outcome of renal surgery. The present study aims at identifying the variants of renal artery based on its origin, multiplicity, and portal of entry in a cohort of people belonging to Southern India and its clinical implications thereof.Methods: Multi-detector CT (MDCT) images of renal vasculature of 100 kidneys from 50 live kidney donors who attended the Department of Nephrology of our institution, from 2016 to 2018 were collected and studied for variations in renal arterial anatomy.Results: Out of the 18% of kidneys observed with multiple renal arteries, 88.8% had double renal arteries (DRA) and 11.1% had triple renal arteries (TRA). Common types of the double renal arteries were - two hilar arteries (31.3%) and one hilar with one inferior polar artery (IPA, 31.3%). Triple renal arteries types - 50% with one hilar, one superior polar, and one inferior polar; 50% with two hilar and one inferior polar artery. No statistically significant association was noted between the incidence of multiple renal arteries and its laterality (p-value=0.193).Conclusion: A thorough understanding of the renal artery variants is crucial for safe and efficacious uro-radiological interventional procedures.

Multidetector computed tomography imaging of squamous cell carcinoma of buccal mucosa

&lt;p&gt;This study aims at describing the role of multidetector computed tomography (MDCT) and CT imaging findings in evaluation of squamous cell carcinoma of buccal mucosa and its staging. Retrospective study of 40 patients who underwent MDCT and were histopathogically proven case of squamous cell carcinoma (SCC) of buccal mucosa patients were included in the study. Plain, arterial, venous phase and puff cheek CT cuts were taken from base of skull till clavicle. The imaging findings in squamous cell carcinoma (SCC) of the oral cavity allow the radiologist to accurately determine the extent and staging of disease thereby help clinicians plan appropriate treatment. 40 such patients were done in which majority of them are male patients-27 as compared to female patients-13. Among these 40 patients, 20 patients had stage IVB cancer, 13 patients had stage IVA, 5 patients had stage II and 2 patients had stage I cancer. No patient included in our study had stage III. Patients’ recovery will depend on how early the cancer is found and staging gives an idea of patients’ possible outcomes. MDCT is non-invasive and cost-effective investigation which helps in evaluating squamous cell carcinoma of buccal mucosa and determines its stage of buccal cancer and guide the therapy accordingly.&lt;/p&gt;

Preoperative measurement of the hiatal surface with MDCT: impact on surgical planning

ObjectiveTo evaluate the accuracy and reproducibility of hiatal surface area (HSA) measurement on dedicated multidetector computed tomography (MDCT) acquisition, in patients, previously subjected to laparoscopic sleeve gastrectomy (LSG), and affected by gastroesophageal reflux disease (GERD). Intraoperative HSA measurement was considered the reference standard.MethodsFifty-two candidates for laparoscopic hiatal hernia repair were prospectively included in the study. MDCT images were acquired during swallowing of oral iodinated contrast media and during strain. Measurements were performed by nine readers divided into three groups according to their experience. Results were compared with intraoperative measurements by means of Spearman correlation coefficient. Reproducibility was evaluated with intra- and interreader agreement by means of weighted Cohen’s kappa and intraclass correlation coefficient (ICC).ResultsSignificant differences between MDCT and intraoperative HSA measurements were observed for swallowing imaging for less experienced readers (p = 0.037, 0.025, 0.028 and 0.019). No other statistically significant differences were observed (p > 0.05). The correlation between HSA measured intraoperatively and on MDCT was higher for strain imaging compared to swallowing (r = 0.94—0.92 vs 0.94—0.89). The overall reproducibility of MDCT HSA measurement was excellent (ICC of 0.95; 95% CI 0,8993 to 0,9840) independently of reader’s experienceConclusionHSA can be accurately measured on MDCT images. This method is reproducible and minimally influenced by reader experience. The preoperative measurement of HSA has potential advantages for surgeons in terms of correct approach to hiatal defects in obese patient.

COMPARISON OF RADIATION DOSE AND IMAGE QUALITY IN HEAD CT SCANS AMONG MULTIDETECTOR CT SCANNERS.

The present study compares three different multidetector CT (MDCT) scanners for routine brain imaging in terms of image quality and radiation doses. The volume CT dose index (CTDIvol), dose-length product (DLP), and effective dose (E) were calculated. Subjective image assessment was obtained based on a scale ranging from 1 (unacceptable) to 5 (optimum). All images scored 3.5 or over, with the 160-slice MDCT images being favoured. For the 4-, 16- and 160-slice MDCT scanners, the respective median values for CTDIvol were 57 mGy, 41 mGy, and 28 mGy; DLP values were 901 mGy.cm, 680 mGy.cm, and 551 mGy.cm; and effective doses were 2 mSv, 1.5 mSv, and 1 mSv, respectively. Compared to the 160-slice MDCT, the dose values for the 4- and 16-slice units were significantly greater. In practice, the CT modality used must be carefully selected to avoid elevated radiation doses and maintain image quality.

No Detection of Pseudocapsule of Tumor-Parenchyma Interface on Multidetector Computed Tomography (MDCT) Images: Clinical Significance and Histological Reflections in Renal Cell Carcinoma

ObjectivePseudocapsule (PS) of tumor-parenchyma interface (TPI) can be detected by MDCT (ctPS) in renal cell carcinoma (RCC) with exceptions. We aim to study the prognostic implications and histological reflections of no detection of ctPS in RCC.Patients and MethodsA total of 210 RCC patients who had MDCT examination and received nephrectomy in our institution were included in the analysis. Absence or presence of ctPS was recognized, and its associations with overall survival (OS) and progression-free survival (PFS), pathological PS (pPS) and vasculature were studied.ResultsA total of 172 (81.9%) patients were recognized to have a ctPS and 38 (18.1%) had no detection of it. They had comparable histology, stage, grade, and necrosis. Patients without a ctPS had significantly shortened overall survival (OS, p = 0.001) and progression-free survival (PFS, p <0.001), the significance of which persisted in multivariable analysis (OS, HR 3.104, p = 0.003; PFS, HR 3.313, p = 0.001). Nearly all tumors (34/38, 89.4%) without a ctPS actually had a pPS being detected and incompleteness of pPS was also irrelevant (p = 0.739). Compared with ctPS presence, those without a ctPS had significantly thinned pPS (0.36 vs 0.43 mm, p = 0.005). In clear-cell histology, those without a ctPS also contained increased vascular density and cross-sectional area of vessels with long diameter ≥200 um in the pPS layer (p = 0.005 and 0.011) and increased vascular density in the 500 um layer outside pPS (p = 0.017).ConclusionAbsence of ctPS on MDCT significantly increases the risk of adverse clinical outcome in RCC. It is the reflection of a thinner pPS and enriched vasculature of TPI rather than absence of pPS itself.

Prognostic Implication of Bone Marrow Abnormality of Appendicular Skeletons Detected By Low-Dose Multidetector Computed Tomography in Patients with Myelodysplastic Syndrome

BackgroundA number of prognostic systems have been developed and validated in patients with myelodysplastic syndrome (MDS). However, the use of the current scoring systems including international prognostic scoring system (IPSS) in determining the prognosis among MDS patient has various conflicting views pertaining to the inclusion of patients with different outcomes. Abnormal red marrow distribution in appendicular skeletons (AS) based on magnetic resonance imaging (MRI) has been described in the literature; however, these findings have not been confirmed. We examined the prognostic implication of medullary abnormalities of AS detected by low-dose whole-body multidetector computed tomography (MDCT) in patients with MDS.Patients and methods147 consecutive patients with MDS diagnosed between January 2009 and May 2017 at Kameda Medical Center were recruited. Diagnosis and classification of MDS were made per 2008 WHO criteria. MDCT studies were performed at the diagnosis of MDS and before the start of any chemotherapy. MDCT images were acquired as previously reported. Medullary pattern of AS were categorized into three groups: (1) Fatty marrow pattern; (2) Focal/scattered marrow pattern; (3) diffuse marrow pattern. To examine if the value of MDCT findings on appendicular marrow has incremental predictive value when the conventional risk factors were controlled, we constructed a receiver operating characteristics (ROC) curve for two logistic regression models. Model 1 was constructed with only conventional risk factors while Model 2 was constructed with conventional risk factors plus MDCT findings.ResultsOf the 147 patients with MDS, there were 47 (32.0%) with fatty, 51 (34.7%) with focal/scattered and 49 (33.3%) with diffuse marrow patterns. Fatty pattern was seen more among non-RAEB patients (76.5%), focal/scattered pattern was about equal while diffuse pattern was more in RAEB patients with 65.3% (P<0.001). The development of AML differed significantly between groups and the highest occurred with diffuse pattern, 30 (61.2%), (P<0.001). Among those with AML, death occurred among 28 (93.3%) . The median LFS was not reached (NR) for fatty pattern, but was 29.2 and 11.1 months for the focal/scattered and diffuse marrow patterns respectively (P<0.001). Similarly, the median OS was NR for fatty pattern but was 40.9 and 14.6 months for the focal/scattered and diffuse marrow patterns respectively (P<0.001). Among the 82 low-risk patients, median survivals of fatty, focal/scattered, and diffuse pattern differed significantly and were NR, 35.2 and 18.2 months respectively for LFS (P<0.001), and NR, 50.9 and 26.3 months respectively for OS (P<0.001). Similarly, for the 65 patients with high-risk MDS, median time were NR, 11.2 and 8.3 months for LFS (P<0.001), and NR, 19.1 and 11.4 months for OS (P<0.001), respectively for fatty, focal/scattered, and diffuse patterns. At multivariate analysis, both focal/scattered and diffuse patterns of medullary marrow of AS remained independently associated with shorter LFS and OS. ROC curve was developed based on the conventional risk model as well as the conventional risk model plus MDCT findings for LFS and OS. Although AUC comparisons showed statistical significance in neither LFS (P=0.108) nor OS (P=0.138), net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were significant for both LFS (NRI 0.43 [95% CI;0.12-0.74], P=0.007 and IDI 0.06 [95% CI; 0.02-0.10], P=0.002) and OS (NRI 0.52 [95% CI; 0.21-0.83], P<0.001 and IDI 0.07 [95% CI; 0.03-0.11], P<0.001).ConclusionOur findings showed a novel method for prognostication of MDS using the medullary findings of AS using MDCT. The prognostic impact of medullary abnormality of AS detected by MDCT has not been described previously. Our findings indicate that the MDCT of appendicular bone marrow is predictive of the prognosis in patients with MDS and has a potential for improving the risk stratification of MDS in conjunction with preexisting scoring systems. [Display omitted] DisclosuresKitadate:Pfizer: Research Funding; Fujimoto: Research Funding; Otsuka: Research Funding; Novartis: Research Funding; Toyama kagaku: Research Funding; Chugai: Research Funding; Asahi Kasei: Research Funding; Eisai: Research Funding; Kyowa Kirin: Research Funding.

Determination of gender based on frontal sinus dimensions using multi-detector computed tomography

Background: Remains of skeleton are used for gender identification of individual. However, when the extreme post-mortem changes occur as in explosions and other mass disasters, identification and gender determination is often difficult. The skull is useful in gender assessment of skeletonized remains. Frontal sinus (FS) may be used in gender identification in recovered intact fragments. The present study is aimed to determine the gender based on frontal sinus dimensions using multi-detector computed tomography (MDCT). In our study two hundred and fifteen frontal sinuses were studied with age range from 20 to70 years with median age of 44 were selected for this study. FS dimensions for bilateral right and left sinuses (transverse, cranio-caudal & anteroposterior dimension) were measured from coronal and axial sections (4-mm slice thickness) using MDCT scanner. Transverse and craniocaudal (CC) dimensions of left frontal sinus was found statistically significant. Lower values for maximum transverse length of left FS and CC in female group were detected in comparison to the male group (p 0.002). Methods: Hospital based retrospective study. CT images of patients were retrieved and dimension of bilateral frontal sinuses were analyzed and was recorded on a data sheet. Results: In our study two hundred and fifteen frontal sinuses were studied with the age range from 20 to70 years with median age of 44 were selected for this study. FS dimensions for bilateral right and left sinuses (transverse, cranio-caudal dimension & anteroposterior lengths) were measured from axial and coronal sections(4-mm slice thickness) using MDCT scanner. Transverse and CC of left FS were found to be statistically significant. Lower values for the maximum transverse and CC dimensions of left FS in female group were detected in comparison to the male group (p 0.002). It can be concluded that FS dimensions measurement especially the left transverse and CC length are valuable in studying sexual dimorphism using MDCT image. Conclusion: From the current work, we concluded that CT scan helps in accurate measurements of FS (especially left anteroposterior length) and are valuable in differentiating gender. Keywords: Frontal sinus, Gender differentiation , Paranasal sinus.

Tumor grade estımatıon of clear cell and papıllary renal cell carcınomas usıng contrast-enhanced MDCT and FSE T2 weıghted MR ımagıng: radıology-pathology correlatıon.

Discrimination of low grade (grade 1-2) renal tumors from high grade (grade 3-4) ones carries crucial importance in terms of the management of these patients and also in the decision-making of appropriate treatment strategies. Our aim was to investigate whether contrast-enhanced multidetector computed tomography (MDCT) and T2 weighted fast spin echo (FSE) magnetic resonance imaging (MRI) could play a specific role in the discrimination of low grade versus high grade tumors in clear cell renal cell carcinoma (ccRCC) and papillary renal cell carcinoma (pRCC) patients. In this study, we retrospectively evaluated 66 RCC patients based on histopathologic findings who had underwent either partial or total nephrectomies. Our cohort consisted of 52 ccRCC and 14 pRCC patients, of whom 50 were male (%76) and 16 were female (%24). Among the 52 ccRCC patients, 18 had both cortico-medullary phase contrast-enhanced CT and MRI, 15 had only cortico-medullary phase CT and 19 had only MRI examination. In the pRCC group, 8 patients had both cortico-medullary phase contrast-enhanced CT and MRI, 3 had only cortico-medullary phase CT and 3 had only MRI. We both calculated mean tumor attenuation values on cortico-medullary phase MDCT images as HU (hounsfield unit) and also tumor mean signal intensity values on FSE T2 weighted MR images, using both region of interest and whole lesion measurements including normal renal cortex. The obtained values were compared with the grading results of the ccRCC and pRCC tumors according to the WHO/International Society of Urological Pathology grading system. A significant positive correlation was found between the mean attenuation values of both tumor subtypes on cortico-medullary phase contrast-enhanced CT and their grades (p < 0.001). High grade tumors exhibited higher mean attenuation values (74.3 ± 22.3 HU) than the low grade tumors (55.2 ± 23.7 HU) in both subtypes. However, a statistically significant correlation was not found between the mean signal intensity values of the two tumor subtypes on FSE T2 weighted MR images and their grades (p > 0.05). Low grade tumors had a mean signal intensity value of 408.9 ± 44.6, while high grade tumors showed a value of 382.1 ± 44.2. The analysis of the ccRCC group patients, yielded a statistically significant correlation between the mean signal intensity values on T2 weighted images and tumor grading (p < 0.001). Low grade (grade 1-2) ccRCC patients exhibited higher mean signal intensity values (475.7 ± 51.3), as compared to those of high grade (grade 3-4) (418.5 ± 45.7) tumors. On the other hand, analysis of the pRCC group patients revealed that there was a significant correlation between the mean attenuation values of tumors on cortico-medullary phase contrast-enhanced CT and their grades (p < 0.001). High grade papillary subtype tumors (54.2 ± 25.2) showed higher mean attenuation values than the low grade (35.5 ± 18.8) ones. Contrast-enhanced MDCT and T2 weighted FSE MRI can play a considerable role in the discrimination of low grade versus high grade tumors of both subtype RCC patients. Thus, these non-invasive evaluation techniques may have positive impact on the determination of the management and treatment strategies of these patients.

Multi-detector computed tomography (MDCT)-based severity score as a prognostic tool in patients with suspected immune checkpoint inhibitor therapy associated colitis.

This study aimed to assess MDCT as a diagnostic and prognostic tool in patients with suspected immune checkpoint inhibitor (ICI)-related colitis. This retrospective cohort study included patients receiving ICIs at three hospitals between 2015 and 2019 who underwent both abdominopelvic MDCT and endoscopic biopsy to workup suspected ICI-related colitis. Two radiologists independently reviewed MDCT images for signs of colitis based on pre-defined features. Diagnostic performance of MDCT was calculated and categorical variables between treatment subgroups were compared. Logistic regression was used to develop proposed MDCT criteria for diagnosis and MDCT severity score based on a combination of MDCT features of colitis to predict the patient outcomes in ICI-related colitis. A total of 118 MDCT scans from 108 patients were evaluated for suspected colitis, with 72 confirmed ICI-related colitis cases. Sensitivity, specificity, PPV, and NPV of MDCT for diagnosis of ICI-related colitis was 81% (58/72), 52 % (24/46), 73% (58/80), and 63% (24/38), respectively. Small bowel involvement was visualized in 25% of cases with ICI-related colitis (18/72). In melanoma patients presenting with diarrhea grade ≥ 2 (n=40), MDCT had the best diagnostic performance for ICI-related colitis (specificity=80% [8/10], PPV=92% [23/25]). MDCT severity scores predicted intravenous steroid use (OR 10.3, p = 0.004), length of stay > 7 days (OR 9.0, p < 0.001), and endoscopic mucosal ulceration (OR 4.7, p = 0.02). MDCT is a useful diagnostic and prognostic tool for evaluating patients with immune checkpoint inhibitor-related colitis. An MDCT-based severity score enables assessment of disease severity and predicts outcome. • MDCT is useful for the diagnosis of colitis in patients receiving immune checkpoint inhibitor (ICI) therapy, and an MDCT-based severity score allows for prognostication of patient outcomes. • MDCT yielded moderate sensitivity (81%) for diagnosis of ICI-related colitis but limited specificity (52%). However, in symptomatic melanoma patients (grade 2-4 diarrhea) with a high pretest probability, MDCT proved useful for diagnosis with a high PPV (92%). • For ICI-related colitis, our proposed MDCT severity score has prognostic value in predicting intravenous steroid use, prolonged length of stay during inpatient admission (> 7 days), and endoscopic mucosal ulceration.

Role of multimodality imaging in the assessment of mechanical prosthetic heart valve dysfunction

In patients with suspected mechanical prosthetic heart valve (PHV) dysfunction, transthoracic and transesophageal echocardiography are considered as the first-line imaging, but may provide unsatisfactory results related to reverberations and acoustic shadowing. This study assessed the value of ECG-gated multidetector computed tomography (MDCT) as a complementary imaging modality in suspected prosthetic dysfunction. Patients with suspected mechanical PHV dysfunction were prospectively recruited between 2018 and 2020 in the cardiology department of Ariana hospital. All patients underwent transthoracic/transesophageal echocardiography and additional MDCT imaging. We compared the diagnosis based on echocardiography and on MDCT information. Our study enrolled 32 patients (median age was 53.7 years: 26–76). 16 patients had an aortic prosthetic valve (50%), 8 patients had a mitral prosthetic valve (25%), 8 patients had mitro-aortic prosthetic valves (25%). An obstructive dysfonction was noticed in 23 patients (72%): a thrombus in 12 cases, a pannus in 4 cases, a mismatch in 2 cases and a reduction in a leaflet motion in 4 cases, a vegetation in one case. A regurgitation was noticed in 4 patients: two paraprosthetic regurgitation and two paraprosthetic aneurysm. Ultrasound imaging and MDCT found same results for mismatach. Echocardiogram was more performant in the diagnosis of thrombosis ( P = 0,02). The addition of MDCT showed incremental value in detecting pannus ( P = 0,02), leaflet restriction and paraprosthetic aneurysm.The leaflet restriction diagnosed by CT in significantly associated with thrombus ( P = 0,03) ( Fig. 1 ). Mechanical PHV dysfunction is rare but life-threatening. A multimodality imaging assessment (ultrasound and CT) is necessary to precise mechanism and indicate the appropriate treatment. MDCT imaging is superior for detecting pannus and leaflet motion restriction.

Multi Detector Computed Tomography Application in Diagnosis and Interventional Management of Facial and Neck Swellings in Children

Background: Facial and neck swellings are frequently encountered in pediatric medicine, and can present a diagnostic dilemma for the clinicians involved. Neck imaging has always been a diagnostic challenge. Multi-Detector row Computed Tomography is an important imaging modality for characterization and presurgical evaluation of neck masses. The aim of the current study was to evaluate the Multi Detector Computed Tomography (MDCT) in diagnosis and interventional management of facial and neck swellings in children. Patients and methods: This is a prospective study included 18 patients (7 males and 11 females) their age range from 8 months to up to 16 years, who were referred to radio diagnosis department from clinical departments at Zagazig University hospitals for assessment of facial and neck swellings by ultrasound (US) and computed tomography (CT) during the period from January 2019 to July 2019. Results: the CT diagnosis of this study was 16.6% hemangioma, venous malformation and lymphatic malformation same percentage 11.11%, benign soft tissue tumor and facial bone tumor due to thalassemia same percentage 5.55%, congenital swelling 16.6% and infectious facial and neck swellings 22.22%.Sixty percentage of cases after sclerotherapy had complete lesion obliteration and 40 % of them had partial lesion obliteration. Sensitivity of MDCT 87.5%, specificity 100%, PPV 100%, NPV 50% and accuracy 90%. Conclusions: MDCT imaging is useful for quick and accurate assessment of facial and neck swelling and the possible improvement of any vascular territory in facial and neck swellings by minimal invasive technique of interventional radiology.

Multidetector CT and cone-beam CT have substantial agreement in detecting dental and sinus abnormalities in equine cadaver heads.

The performance of cone-beam CT (CBCT) systems compared to conventional helical multidetector CT (MDCT) imaging of the equine head is unknown. The aim of this prospective, method-comparison study was to compare the ability of CBCT and MDCT to detect abnormalities in equine cadaver heads. Eleven equine cadaver heads were scanned using a CBCT scanner and a 64-slice MDCT scanner. Consensus evaluations for CBCT and MDCT scans were performed by three observers. Identified abnormalities were grouped into subcategories with a focus on dental abnormalities. Kappa agreement values between detected abnormalities for CBCT and MDCT methods were calculated. Of 468 teeth evaluated, 122 (26.1%) were found to have abnormalities (including in 58 infundibula and 7 pulps) using MDCT and 105 (22.4%) were found to have abnormalities (including in 52 infundibula and 2 pulps) using CBCT. The agreement between CBCT and MDCT was almost perfect for overall detection of dental abnormalities (k=0.90) with k=1 for diastema k=0.95 for clinical crown abnormalities, and k=0.93 for infundibular abnormalities. However, the detection of pulp changes by CBCT was only moderate k=0.44. Increased scatter radiation, non-calibrated Hounsfield Unit and artefacts in CBCT images made accurate identification of the pulp density difficult. In conclusion, CBCT results were similar to conventional MDCT for the majority of dental abnormalities, however, pulp abnormalities were not reliably identified using CBCT, potentially limiting its clinical use for detecting endodontic disease in its current form. Further comparison with more cases with confirmed dental disease and studies in clinical cases are warranted.

Multidetector Computed Tomographic Evaluation of Complications Following Lung Transplantation with Clinical Correlation

Context: Lung transplantation (LT) is now being performed for end-stage lung and heart-lung disease in a few centers in India. Experience in multidetector computed tomography (MDCT) evaluation of posttransplant complications is currently limited and evolving. Aims: This study analyses the early experience in our center regarding the imaging features of complications following LT with clinical outcome correlation and identify the role of MDCT. Methodology: A retrospective study of patients who underwent LT and had MDCT imaging from January 2017 to March 2019 was performed. There were 22 patients in this period whose clinical course and CT scans were studied. Results: The complications encountered include pleural effusions, atelectasis, bronchostenosis, and reperfusion injury. Rare complications included pulmonary thromboembolism and rejection. The accuracy of computed tomography (CT) imaging in airway evaluation was high but was limited in characterization of consolidation as either infective or noninfective. Conclusions: CT is the noninvasive imaging modality of choice in evaluating chronic rejection, airway complications such as bronchostenosis and pulmonary thromboembolism. Clinical, laboratory, and biopsy correlation are needed to diagnose infection or acute rejection, both of which can present with consolidation. Temporal evaluation of events is critical. Familiarity and awareness by the radiologist are crucial for good clinical outcome.

Role of multi-detector computed tomography in severity assessment of cases of acute pancreatitis.

The mortality and morbidity of acute pancreatitis is high, especially in the severe variant. The present study was performed to study the role of multi-detector computed tomography (MDCT) in grading the severity of acute pancreatitis and to compare the scoring system with the revised Atlanta classification (RAC) and with the outcomes of acute pancreatitis. Asingle-centre cross-sectional observational study was conducted between November 2017 and March 2019 with asample size of 152patients. Patients underwent a128-slice contrast-enhanced CT (CECT) of the whole abdomen. Sequential organ failure assessment (SOFA) scores were calculated for all cases. Patients were followed until discharge or death and the outcomes such as hospital stay, intensive care unit (ICU) stay, evidence of organ failure, infection, need for intervention and death were tested with the modified computed tomography severity index (MCTSI) and RAC. Males constituted the majority of the study population (2.4:1). As per MCTSI, 25patients (16.5%) had mild pancreatitis, 49 (32.2%) had moderately severe pancreatitis and 78 (51.3%) had severe acute pancreatitis. There was agood concordance between MCTSI and RAC. There was astatistically significant association of MCTSI and RAC with hospital stay, need for ICU stay, organ failure and requirement for intervention; however, there was no statistically significant association with infectious complications and mortality. The MDCT is avery useful investigation in the diagnosis and management of acute pancreatitis. The threshold to opt for MDCT imaging in acute pancreatitis should be low for performing the timely interventions required in acute pancreatitis.

Computer tomographic differential diagnosis of ameloblastoma and odontogenic keratocyst: classification using a convolutional neural network.

To analyse the automatic classification performance of a convolutional neural network (CNN), Google Inception v3, using tomographic images of odontogenic keratocysts (OKCs) and ameloblastomas (AMs). For construction of the database, we selected axial multidetector CT images from patients with confirmed AM (n = 22) and OKC (n = 18) based on a conclusive histopathological report. The images (n = 350) were segmented manually and data augmentation algorithms were applied, totalling 2500 images. The k-fold × five cross-validation method (k = 2) was used to estimate the accuracy of the CNN model. The accuracy and standard deviation (%) of cross-validation for the five iterations performed were 90.16 ± 0.95, 91.37 ± 0.57, 91.62 ± 0.19, 92.48 ± 0.16 and 91.21 ± 0.87, respectively. A higher error rate was observed for the classification of AM images. This study demonstrated a high classification accuracy of Google Inception v3 for tomographic images of OKCs and AMs. However, AMs images presented the higher error rate.

Comparison of the Hounsfield Unit Values Obtained From Cone-Beam Computed Tomography (CBCT) and Multidetector Computed Tomography (MDCT) Images for Different Bone Densities

Background and objective: In recent years, cone-beam computed tomography (CBCT) has become a key diagnostic tool in dentistry. CBCT can provide 3D images of the maxillofacial area to help dental practitioners in diagnosis and treatment, especially implant placement and treatment of pathogenic lesions. This study aimed to compare the Hounsfield Unit (HU) values obtained from CBCT images for bones of different densities with the corresponding HU values from MDCT images.&#x0D; Materials and methods: cube-shaped bone blocks of identical size were cut from the middle section of the cow ribs and femur area such that they had a layer of cortical bone in their buccal, lingual, and top surfaces and trabecular bone in the middle. MDCT scans were performed using a Somatom Sensation Ct Scanner. After determining HU from the results of these scans, nine suitable specimens from different ranges of HU were chosen for comparison. HU of the CBCT images was computed by the dedicated software of the CBCT machine. Finally, HU values obtained from MDCT and CBCT were compared. Data analysis was performed using SPSS version 25 at the 0.05 significance level.&#x0D; Results: The results showed a statistically significant difference between the mean HU from MDCT images and the mean HU from CBCT images (P&lt;0.05). For similar specimens, CBCT produced higher mean HU values than MDCT. The Pearson correlation test detected a significant direct relationship between the HU values of specimens in MDCT and CBCT (P&lt;0.05).&#x0D; Conclusion: For the tools and software used in this study, there was no significant difference between the HU values obtained from MDCT and CBCT, but the mean HU obtained from CBCT was higher than that from MDCT.

Evaluation of radiomics and machine learning in identification of aggressive tumor features in renal cell carcinoma (RCC).

The purpose of this study was to evaluate the use of CT radiomics features and machine learning analysis to identify aggressive tumor features, including high nuclear grade (NG) and sarcomatoid (sarc) features, in large renal cell carcinomas (RCCs). CT-based volumetric radiomics analysis was performed on non-contrast (NC) and portal venous (PV) phase multidetector computed tomography images of large (> 7cm) untreated RCCs in 141 patients (46W/95M, mean age 60years). Machine learning analysis was applied to the extracted radiomics data to evaluate for association with high NG (grade 3-4), with multichannel analysis for NG performed in a subset of patients (n = 80). A similar analysis was performed in a sarcomatoid rich cohort (n = 43, 31M/12F, mean age 63.7 years) using size-matched non-sarcomatoid controls (n = 49) for identification of sarcomatoid change. The XG Boost Model performed best on the tested data. After manual and machine feature extraction, models consisted of 3, 7, 5, 10 radiomics features for NC sarc, PV sarc, NC NG and PV NG, respectively. The area under the receiver operating characteristic curve (AUC) for these models was 0.59, 0.65, 0.69 and 0.58 respectively. The multichannel NG model extracted 6 radiomic features using the feature selection strategy and showed an AUC of 0.67. Statistically significant but weak associations between aggressive tumor features (high nuclear grade, sarcomatoid features) in large RCC were identified using 3D radiomics and machine learning analysis.

Evaluation of iliac venous variations with multidetector computed tomography.

There are many variations of the iliac vein, and it is aimed to evaluate these variations using multidetector computed tomography (MDCT). Pelvic MDCT images of 1071 adult patients (576 males; 495 females; age range 18-94years; mean age 50.3years) were retrospectively evaluated. Reconstruction images of the pelvic region in sagittal and coronal planes were evaluated. Except for the usual iliac venous anatomy, all types of iliac vein connections were defined as "iliac venous variation". Of the 1071 patients, 84.2% were considered as type 1 (usual). Different variations were observed in 15.8% of the patients, of whom, 63.9% of were male and 36.1% female, and this gender difference was statistically significant (p < 0.05). The rates of variations detected in the study were type 2 (49.7%), type 3 (29%), type 4 (4.7%), type 5 (6.5%), type 6 (4.8%), type 7 (1.8%) and type 8 (3.6%) respectively. New subtypes that we named as type 3c, type 6f, type 6 × and type 7b were first determined in our study. Knowledge and evaluation of iliac venous variations before pelvic surgery or interventional procedures is of importance in preventing possible complications.