A Narrative Review on Current Diagnostic Imaging Tools for Dentomaxillofacial Abnormalities in Children.

The current review narrates the findings and discusses the available diagnostic tools for detecting structural abnormalities. The review discusses several diagnostic tools, such as magnetic resonance imaging, cone beam computed tomography, multi detector row CT and positron emission tomography. The vital findings and comparative analysis of different diagnostic tools are presented in this review. The present review also discusses the advent of newer technologies, such as the HyperionX9 scanner with less field of view and 18F-FDG PET/CT (positron emission tomography with 2-deoxy-2-[fluorine-18] fluoro-D-glucose, integrated with computed tomography), which can give more efficient imaging of dentomaxillofacial structures. The discussion of effective comparative points enables this review to reveal the available diagnostic tools that can be used in the detection of dentomaxillofacial abnormalities in the pediatric population. The advantages and disadvantages of each tool are discussed, and the findings of past publications are also presented. Overall, this review discusses the technical details and provides a comparative analysis of updated diagnostic techniques for dentomaxillofacial diagnosis.

Detection of posterior superior alveolar artery using multi-detector row CT: a retrospective study focused on age-related changes.

PURPOSE: The posterior superior alveolar artery (PSAA) is a branch of the maxillary artery that supplies the lateral sinus wall and overlying membrane. This artery is one among several arteries in which arterial damage during surgery can cause massive and fatal bleeding. The purpose of this study was to detect the PSAA using multi-detector row computed tomography (MDCT) by age. MATERIALS AND METHODS: The present study was approved by our university ethics committee (EC19-010). The study included 230 patients (110 males, 120 females; ages 5-91 years, average age 42.5 years) who underwent MDCT of the jaw. The subjects were divided into two groups, one group in which the PSAA was observable and another in which the PSAA was not observable, to perform the Mann-Whitney U test. To perform the Tukey-Kramer multiple comparison test, the subjects were divided into the following ten groups depending on their age: 5-9 years, 10-19 years, 20-29 years, 30-39 years, 40-49 years, 50-59 years, 60-69 years, 70-79 years, 80-89 years, and 90-91 years. RESULTS: The PSAA was identified in 74.5% (5-91 years) of the maxillary sinuses. The average age of subjects in whom the PSAA was observable was 33.4 years, and the average age of subjects in whom the PSAA was not observable was 11.3 years, indicating a significant difference between these two groups (p < 0.01). A comparison by age group showed a significant difference (p < 0.05). CONCLUSIONS: The detection ratio for the PSAA using MDCT increased with increasing age of the subject, reaching a high detection ratio of 94% in adults. This study has shown that MDCT is a very useful tool to observe the PSAA.

The utility of coronary computed tomography angiography in elderly patients.

BACKGROUND: Coronary computed tomography angiography (CCTA) is often avoided in elderly patients due to a presumption that a high proportion of patients will have heavily calcified plaque limiting an accurate assessment. We sought to assess the image quality, luminal stenosis and utility of CCTA in elderly patients with suspected coronary artery disease (CAD) and stable chest pain. METHODS: Retrospective analysis of elderly patients (> 75 years) who underwent 320-detector row CCTA between 2012-2017 at MonashHeart. The CCTA was analysed for degree maximal coronary stenosis by CAD-RADS classification, image quality by a 5-point Likert score (1-poor, 2-adequate, 3-good, 4-very good, 5-excellent) and presence of artefact limiting interpretability. RESULTS: 1011 elderly patients (62% females, 78.8 ± 3.3 years) were studied. Cardiovascular risk factor prevalence included: hypertension (65%), hyperlipidaemia (48%), diabetes (19%) and smoking (21%). The CCTA was evaluable in 68% of patients which included 52% with non-obstructive CAD (< 50% stenosis), 48% with obstructive CAD (> 50%) stenosis. Mean Likert score was 3.1 ± 0.6 corresponding to good image quality. Of the 323 (32%) of patients with a non-interpretable CCTA, 80% were due to calcified plaque and 20% due to motion artefact. Male gender (P = 0.009), age (P = 0.02), excess motion (P < 0.01) and diabetes mellitus (P = 0.03) were associated with non-interpretable CCTA. CONCLUSION: Although CCTA is a feasible non-invasive tool for assessment of elderly patients with stable chest pain, clinicians should still be cautious about referring elderly patients for CCTA. Patients who are male, diabetic and >78 years of age are significantly less likely to have interpretable scans.

Role of the anterior fissure vein in ventral or dorsal resection at Segment 8 of liver.

BACKGROUND: The vein that runs between ventral and dorsal Segment 8 is called the anterior fissure vein (AFV). AFV is sometimes needed as a boundary for Subsegmentectomy in Segment 8. The aim of the present study was to investigate the AFV to determine whether the AFV can be used a landmark for subsegmentectomy of the liver at Segment 8. METHODS: We analyzed data from 151 patients who had undergone abdominal computed tomographic (CT) examinations. The position of the AFV is identified by determining whether the AFV drains flows into the proximal, medial, or distal portion of the middle hepatic vein (MHV) or right hepatic vein (RHV). Furthermore, the proximal region is divided into 2 halves; the proximal portion is designated as P1 and the distal portion is designated as P2. RESULTS: The AFV could be identified in 78.8% (119/151) of the patients. The AFV flowed into the MHV in 84.9% of the patients and into the RHV in 15.1%. Among the former, the AFV flowed into the proximal MHV in 69.7% of the patients. CONCLUSIONS: Although the AFV might not be easily identifiable, the AVF can be used to determine the border between the ventral and dorsal portions of Segment 8. The AFV should thus be used as a landmark for Subsegmentectomy.

Role of time-resolved-CTA in intracranial arteriovenous malformation evaluation at 128-slice CT in comparison with digital subtraction angiography.

Introduction The present study aimed to evaluate the accuracy of time-resolved-computed tomographic angiography (TR-CTA) on a 128-slice CT scanner vis-à-vis cerebral digital subtraction angiography (DSA) in defining the morphological and haemodynamic characteristics of cerebral arteriovenous malformation (AVM). Methods Twenty-one patients (age range 10-46, mean 24.8 years) with clinical suspicion of AVM and three patients (age range 23-35, mean 24.3 years) with diagnosed AVM who were on follow-up underwent DSA and TR-CTA, on average 1.5 days apart. Three independent neuroradiologists analysed both studies in a blinded fashion based on the following parameters: AVM location, arterial feeder territories, venous drainage pattern, nidus flow characteristics, venous outflow obstruction, arterial feeder enlargement, external carotid artery feeder, location of aneurysm if any, leptomeningeal and transdural recruitment, neoangiogenesis, and pseudophlebitic pattern. Results The TR-CTA correctly demonstrated AVM in all 21 positive cases. It concordantly detected location (21/21), venous drainage pattern (21/21), nidus flow characteristics (21/21), and the venous outflow obstruction (9/9). However, discordance was seen in the demonstration of the arterial feeder (2/45) ( p = 0.49), arterial enlargement (13/17) ( p = 0.103), external carotid artery feeder (0/1), aneurysmal location (3/5) ( p = 0.40), leptomeningeal recruitment (1/3) ( p = 0.40), neoangiogenesis (0/4) ( p = 0.028) and in the pseudophlebitic pattern (2/5) ( p = 0.167) demonstration. Conclusions The results suggest that TR-CTA can provide the important features of cerebral AVM which are required in patient management.

Periportal low attenuation associated with liver metastasis from colorectal cancer: evaluation using multi-detector-row CT with pathological correlation.

OBJECTIVES: Periportal low attenuation (PPLA) associated with metastatic liver cancer is occasionally seen on multi-detector-row CT (MDCT). The purpose of this study was to investigate the MDCT patterns of the PPLA and to correlate it with pathological findings. METHODS: We retrospectively reviewed the MDCT images of 63 patients with metastatic liver cancers from colorectal adenocarcinoma. On MDCT scans, PPLA associated with liver metastasis was visualized in six patients with colorectal cancer. In these six patients who had undergone surgical resection, the radiologic-pathologic correlation was analyzed. All patients underwent a single contrast-enhanced MDCT within 1 month before surgical resection. The six liver cancers were pathologically proven to be moderately differentiated adenocarcinoma. We assessed the PPLA on MDCT concerning the distribution patterns and contrast enhancement with pathological correlation. RESULTS: In five of the patients, the PPLA extended to the hilar side from metastatic liver cancer. Pathologically, there was no cancer invasion into the intra-hepatic periportal area; however, massive lymphedema and fibrosis occurred in all six cases. CONCLUSIONS: PPLA on the hilar and peripheral sides of hepatic metastasis from colorectal cancer may be present suggesting lymphedema and fibrosis of portal tracts not always indicating cancer infiltration.

Low contrast media volume in pre-TAVI CT examinations.

PURPOSE: To evaluate image quality using reduced contrast media (CM) volume in pre-TAVI assessment. METHODS: Forty-seven consecutive patients referred for pre-TAVI examination were evaluated. Patients were divided into two groups: group 1 BMI < 28 kg/m(2) (n = 29); and group 2 BMI > 28 kg/m(2) (n = 18). Patients received a combined scan protocol: retrospective ECG-gated helical CTA of the aortic root (80kVp) followed by a high-pitch spiral CTA (group 1: 70 kV; group 2: 80 kVp) from aortic arch to femoral arteries. All patients received one bolus of CM (300 mgI/ml): group 1: volume = 40 ml; flow rate = 3 ml/s, group 2: volume = 53 ml; flow rate = 4 ml/s. Attenuation values (HU) and contrast-to-noise ratio (CNR) were measured at the levels of the aortic root (helical) and peripheral arteries (high-pitch). Diagnostic image quality was considered sufficient at attenuation values > 250HU and CNR > 10. RESULTS: Diagnostic image quality for TAVI measurements was obtained in 46 patients. Mean attenuation values and CNR (HU ± SD) at the aortic root (helical) were: group 1: 381 ± 65HU and 13 ± 8; group 2: 442 ± 68HU and 10 ± 5. At the peripheral arteries (high-pitch), mean values were: group 1: 430 ± 117HU and 11 ± 6; group 2: 389 ± 102HU and 13 ± 6. CONCLUSION: CM volume can be substantially reduced using low kVp protocols, while maintaining sufficient image quality for the evaluation of aortic root and peripheral access sites. KEY POINTS: • Image quality could be maintained using low kVp scan protocols. • Low kVp protocols reduce contrast media volume by 34-67 %. • Less contrast media volume lowers the risk of contrast-induced nephropathy.

Semiautomatic three-dimensional CT ventricular volumetry in patients with congenital heart disease: agreement between two methods with different user interaction.

To assess agreement between two semi-automatic, three-dimensional (3D) computed tomography (CT) ventricular volumetry methods with different user interactions in patients with congenital heart disease. In 30 patients with congenital heart disease (median age 8 years, range 5 days-33 years; 20 men), dual-source, multi-section, electrocardiography-synchronized cardiac CT was obtained at the end-systolic (n = 22) and/or end-diastolic (n = 28) phase. Nineteen left ventricle end-systolic (LV ESV), 28 left ventricle end-diastolic (LV EDV), 22 right ventricle end-systolic (RV ESV), and 28 right ventricle end-diastolic volumes (RV EDV) were successfully calculated using two semi-automatic, 3D segmentation methods with different user interactions (high in method 1, low in method 2). The calculated ventricular volumes of the two methods were compared and correlated. A P value <0.05 was considered statistically significant. LV ESV (35.95 ± 23.49 ml), LV EDV (88.76 ± 61.83 ml), and RV ESV (46.87 ± 47.39 ml) measured by method 2 were slightly but significantly smaller than those measured by method 1 (41.25 ± 26.94 ml, 92.20 ± 62.69 ml, 53.61 ± 50.08 ml for LV ESV, LV EDV, and RV ESV, respectively; P ≤ 0.02). In contrast, no statistically significant difference in RV EDV (122.57 ± 88.57 ml in method 1, 123.83 ± 89.89 ml in method 2; P = 0.36) was found between the two methods. All ventricular volumes showed very high correlation (R = 0.978, 0.993, 0.985, 0.997 for LV ESV, LV EDV, RV ESV, and RV EDV, respectively; P < 0.001) between the two methods. In patients with congenital heart disease, 3D CT ventricular volumetry shows good agreement and high correlation between the two methods, but method 2 tends to slightly underestimate LV ESV, LV EDV, and RV ESV.

Intramural location and size of arterial calcification are associated with stenosis at carotid bifurcation.

PURPOSE: The purpose of this study was to investigate the association between internal carotid artery (ICA) stenosis and intramural location and size of calcification at the ICA origins and the origins of the cervical arteries proximal to the ICA. METHOD: A total of 1139 ICAs were evaluated stenosis and calcification on the multi-detector row CT angiography. The intramural location was categorized into none, outside and inside location. The calcification size was evaluated on the 4-point grading scale. The multivariate analyses were adjusted for age, serum creatinine level, hypertension, hyperlipidemia, diabetes mellitus, smoking and alcohol habits. RESULTS: Outside calcification at the ICA origins showed the highest multivariate odds ratio (OR) for the presence of ICA stenosis (30.0) and severe calcification (a semicircle or more of calcification at the arterial cross-sectional surfaces) did the second (14.3). In the subgroups of >70% ICA stenosis, the multivariate OR of outside location increased to 44.8 and that of severe calcification also increased to 32.7. Four of 5 calcified carotid plaque specimens extracted by carotid endarterectomy were histologically confirmed to be calcified burdens located outside the internal elastic lamia which were defined as arterial medial calcification. CONCLUSIONS: ICA stenosis was strongly associated with severe calcification located mainly outside the carotid plaque. Outside calcification at the ICA origins should be evaluated separately from inside calcification, as a marker for the ICA stenosis. Additionally, we found that calcification at the origins of the cervical arteries proximal to the ICA was significantly associated with the ICA stenosis.

Calcification at orifices of aortic arch branches is a reliable and significant marker of stenosis at carotid bifurcation and intracranial arteries.

PURPOSE: Simple rating scale for calcification in the cervical arteries and the aortic arch on multi-detector computed tomography angiography (MDCTA) was evaluated its reliability and validity. Additionally, we investigated where is the most representative location for evaluating the calcification risk of carotid bifurcation stenosis and atherosclerotic infarction in the overall cervical arteries covering from the aortic arch to the carotid bifurcation. METHOD: The aortic arch and cervical arteries among 518 patients (292 men, 226 women) were evaluated the extent of calcification using a 4-point grading scale for MDCTA. Reliability, validity and the concomitant risk with vascular stenosis and atherosclerotic infarction were assessed. RESULTS: Calcification was most frequently observed in the aortic arch itself, the orifices from the aortic arch, and the carotid bifurcation. Compared with the bilateral carotid bifurcations, the aortic arch itself had a stronger inter-observer agreement for the calcification score (Fleiss' kappa coefficients; 0.77), but weaker associations with stenosis and atherosclerotic infarction. Calcification at the orifices of the aortic arch branches had a stronger inter-observer agreement (0.74) and enough associations with carotid bifurcation stenosis and intracranial stenosis. In addition, the extensive calcification at the orifices from the aortic arch was significantly associated with atherosclerotic infarction, similar to the calcification at the bilateral carotid bifurcations. CONCLUSIONS: The orifices of the aortic arch branches were the novel representative location of the aortic arch and overall cervical arteries for evaluating the calcification extent. Thus, calcification at the aortic arch should be evaluated with focus on the orifices of 3 main branches.

Mesothelial cyst of the round ligament mimicking a metastasis: a case report.

A mesothelial cyst of the round ligament is a rare cause of an inguinal mass. Clinically, it is frequently misdiagnosed as one of commoner diseases such as an inguinal hernia, femoral hernia, lipoma, and lymphadenopathy upon physical examination. Some previous reports elaborated the sonographic features of a mesothelial cyst of the round ligament. However, to our knowledge, few reports have described the CT features of a mesothelial cyst. We illustrated here the sonographic and multidetector CT features of a case of a mesothelial cyst of the round ligament that presented as an inguinal palpable mass and mimicked a metastasis in a patient with a Sertoli-Leydig cell tumor of the ovary.

Multi-detector row computed tomography findings of pelvic congestion syndrome caused by dilated ovarian veins.

OBJECTIVE: To evaluate the efficacy of multi-detector row CT (MDCT) on pelvic congestion syndrome (PCS), which is often overlooked or poorly visualized with routine imaging examination. MATERIALS AND METHODS: We evaluated the MDCT features of 40 patients with PCS (mean age, 45 years; range, 29-60 years) using axial, coronal, sagittal, 3D volume-rendered, and Maximum Intensity Projection MIP images. RESULTS: MDCT revealed pelvic varices and ovarian vein dilatations in all patients. Bilateral ovarian vein dilatation was present in 25 patients, and 15 patients had unilateral dilatation. While 12 cases of secondary pelvic varices occurred simultaneously with a retroaortic left renal vein, 10 cases were due solely to a mass obstruction or stenosis of venous structures. CONCLUSION: MDCT is an effective tool in the evaluation of PCS, and it has more advantages than other imaging modalities.

Mesothelial Cyst of the Round Ligament Mimicking a Metastasis: a Case Report

A mesothelial cyst of the round ligament is a rare cause of an inguinal mass. Clinically, it is frequently misdiagnosed as one of commoner diseases such as an inguinal hernia, femoral hernia, lipoma, and lymphadenopathy upon physical examination. Some previous reports elaborated the sonographic features of a mesothelial cyst of the round ligament. However, to our knowledge, few reports have described the CT features of a mesothelial cyst. We illustrated here the sonographic and multidetector CT features of a case of a mesothelial cyst of the round ligament that presented as an inguinal palpable mass and mimicked a metastasis in a patient with a Sertoli-Leydig cell tumor of the ovary.

Advanced Gastric Cancer and Perfusion Imaging Using a Multidetector Row Computed Tomography: Correlation with Prognostic Determinants

OBJECTIVE: To investigate the relationship between the perfusion CT features and the clinicopathologically determined prognostic factors in advanced gastric cancer cases. MATERIALS AND METHODS: A perfusion CT was performed on 31 patients with gastric cancer one week before surgery using a 16-channel multi-detector CT (MDCT) instrument. The data were analyzed with commercially available software to calculate tumor blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface (PS). The microvessel density (MVD), was evaluated by immunohistochemical staining of the surgical specimens with anti-CD34. All of the findings were analyzed prospectively and correlated with the clinicopathological findings, which included histological grading, presence of lymph node metastasis, serosal involvement, distant metastasis, tumor, node, metastasis (TNM) staging, and MVD. The statistical analyses used included the Student's t-test and the Spearman rank correlation were performed in SPSS 11.5. RESULTS: The mean perfusion values and MVD for tumors were as follows: BF (48.14+/-16.46 ml/100 g/min), BV (6.70+/-2.95 ml/100 g), MTT (11.75+/-4.02 s), PS (14.17+/-5.23 ml/100 g/min) and MVD (41.7+/-11.53). Moreover, a significant difference in the PS values was found between patients with or without lymphatic involvement (p = 0.038), as well as with different histological grades (p = 0.04) and TNM stagings (p = 0.026). However, BF, BV, MTT, and MVD of gastric cancer revealed no significant relationship with the clinicopathological findings described above (p > 0.05). CONCLUSION: The perfusion CT values of the permeable surface could serve as a useful prognostic indicator in patients with advanced gastric cancer.

A new method for measuring coronary artery diameters with CT spatial profile curves.

PURPOSE: Coronary artery vascular edge recognition on computed tomography (CT) angiograms is influenced by window parameters. A noninvasive method for vascular edge recognition independent of window setting with use of multi-detector row CT was contrived and its feasibility and accuracy were estimated by intravascular ultrasound (IVUS). METHODS: Multi-detector row CT was performed to obtain 29 CT spatial profile curves by setting a line cursor across short-axis coronary angiograms processed by multi-planar reconstruction. IVUS was also performed to determine the reference coronary diameter. IVUS diameter was fitted horizontally between two points on the upward and downward slopes of the profile curves and Hounsfield number was measured at the fitted level to test seven candidate indexes for definition of intravascular coronary diameter. The best index from the curves should show the best agreement with IVUS diameter. RESULTS: Of the seven candidates the agreement was the best (agreement: 16±11%) when the two ratios of Hounsfield number at the level of IVUS diameter over that at the peak on the profile curves were used with water and with fat as the background tissue. These edge definitions were achieved by cutting the horizontal distance by the curves at the level defined by the ratio of 0.41 for water background and 0.57 for fat background. CONCLUSIONS: Vascular edge recognition of the coronary artery with CT spatial profile curves was feasible and the contrived method could define the coronary diameter with reasonable agreement.

MDCT Application in the Vascular System

Helical CT has improved with faster gantry rotation, more powerful X-ray tubes, and improved interpolation algorithms; however, the greatest advance has been made by the recent introduction of multi detector-row computed tomography (MDCT) scanners. Fundamental advantages of MDCT include substantially shorter acquisition times, retrospective creation of thinner or thicker sections from the same raw data, and improved threedimensional (3-D) rendering with diminished helical artifacts. While these features will likely be important to many applications of CT scanning, the greatest impact has been on CT angiography. The advantages of MDCT over single detector-row CT scanners when imaging the vascular system can be broken down into three fundamental improvements, that is, speed (faster scan time), distance (longer coverage), and section thickness (better resolution). This article will focus on how the MDCT technology has substantially improved imaging of the vascular system, including pulmonary artery, aorta and extremity vessels.

Study on the blood supply and collateral circulation of esophageal gastric varicose / 中华消化内镜杂志

Objective To detect the esophageal and fundal varices and their related collateral ves-sels by multi-detector row CT ( MDCT) in helping to find out the objective evidences for selecting treatment measure and predicting prognosis. Methods Fifty-one patients with clinical diagnosis of cirrhosis were in-cluded in this study. Esophageal varices were confirmed by endoscopy in all patients, of which 31 accompa-nied with fundal varices. All patients underwent MDCT angiography to demonstrate collaterals between the systemic and portal circulation as well as the esophageal varicose. Results Good or excellent image quality was obtained in all patients. Gastric fundal varices were found in 31 of 51 patients (60. 8% )by endoscopies. By MDCT angiography esophageal varies were confirmed in all patients, gastric fundal varices were in 32 of 51 (62. 7% ). There are high degree of concordance Kappa =0. 876 between them. Esophageal varices were supplied mainly by the left gastric vein ( LGV) , by anterior branch of LGV alone in 30 of 51 (58. 8% ). There were paraesophageal veins in 21 of 51 patients (41.2%). Gastric fundal varices were supplied by LGV in 24 of 32 patients (75% ), by short gastric veins /posterior gastric veins in 3 of 32 patients (9. 4% ) and by short gastric veins /posterior gastric veins and LGV together in 5 of 32 patients ( 15. 6% ). Short gas-tric veins and posterior gastric veins participate in forming of esophageal varices in these patients. Conclusion MDCT angiography shows an excellent vascular maps and highly in concordance with endoscopy in terms of the detection of esophageal and gastric fundal varices. Esophagal varices were supplied mainly by LGV, more than half of them were by its anterior branch, and paraesophageal veins participated to it in some patients too. The blood flow in gastric fundal varices were supplied from LGV in most of the patients, and the rest from short gastric veins.