Extravasated contrast volumetric assessment on computed tomography angiography in gastrointestinal bleeding:A useful predictor of positive angiographic findings

BACKGROUND Gastrointestinal bleeding(GIB)is a severe and potentially life-threatening condition,especially in cases of delayed treatment.Computed tomography angiography(CTA)plays a pivotal role in the early identification of upper and lower GIB and in the prompt treatment of the haemorrhage.AIM To determine whether a volumetric estimation of the extravasated contrast at CTA in GIB may be a predictor of subsequent positive angiographic findings.METHODS In this retrospective single-centre study,35 patients(22 men;median age 69 years;range 16-92 years)admitted to our institution for active GIB detected at CTA and further submitted to catheter angiography between January 2018 and February 2022 were enrolled.Twenty-three(65.7%)patients underwent endoscopy before CTA.Bleeding volumetry was evaluated in both arterial and venous phases via a semi-automated dedicated software.Bleeding rate was obtained from volume change between the two phases and standardised for unit time.Patients were divided into two groups,according to the angiographic signs and their concordance with CTA.RESULTS Upper bleeding accounted for 42.9%and lower GIB for 57.1%.Mean haemoglobin value at the admission was 7.7 g/dL.A concordance between positive CTA and direct angiographic bleeding signs was found in 19(54.3%)cases.Despite no significant differences in terms of bleeding volume in the arterial phase(0.55 mL vs 0.33 mL,P=0.35),a statistically significant volume increase in the venous phase was identified in the group of patients with positive angiography(2.06 mL vs 0.9 mL,P=0.02).In the latter patient group,a significant increase in bleeding rate was also detected(2.18 mL/min vs 0.19 mL/min,P=0.02).CONCLUSION In GIB of any origin,extravasated contrast volumetric analysis at CTA could be a predictor of positive angiography and may help in avoiding further unnecessary procedures.

Clinical anatomy of hepatic vessels by computed tomography angiography:A minireview

The liver has a complex vascular anatomy with a unique dual blood supply.Clinical conditions of the liver vary widely and include disorders originating in the vascular and biliary systems as well as the parenchyma.In most vascular disorders,the effects on the liver are generally subclinical because of its abundant blood supply.However,early diagnosis of such vascular diseases can significantly reduce patient morbidity and mortality.Because imaging findings of vascular disease are not always readily apparent,diagnosis can be difficult.Computed tomography angiography is an excellent imaging modality for visualizing the vascular anatomy of patients for treatment planning.In this review article,we focus on the vascular anatomy of the liver and the imaging findings in some acute hepatic vascular diseases.

Emerging role of computed tomography coronary angiography in evaluation of children with Kawasaki disease

Coronary artery abnormalities are the most important complications in children with Kawasaki disease(KD).Two-dimensional transthoracic echocardiography currently is the standard of care for initial evaluation and follow-up of children with KD.However,it has inherent limitations with regard to evaluation of mid and distal coronary arteries and,left circumflex artery and the poor acoustic window in older children often makes evaluation difficult in this age group.Catheter angiography(CA)is invasive,has high radiation exposure and fails to demonstrate abnormalities beyond lumen.The limitations of echocardiography and CA necessitate the use of an imaging modality that overcomes these problems.In recent years advances in computed tomography technology have enabled explicit evaluation of coronary arteries along their entire course including major branches with optimal and acceptable radiation exposure in children.Computed tomography coronary angiography(CTCA)can be performed during acute as well as convalescent phases of KD.It is likely that CTCA may soon be considered the reference standard imaging modality for evaluation of coronary arteries in children with KD.

Radiation dose analysis of computed tomography coronary angiography in Children with Kawasaki disease

BACKGROUND There is evolving role of computed tomography coronary angiography(CTCA)in non-invasive evaluation of coronary artery abnormalities in children with Kawasaki disease(KD).Despite this,there is lack of data on radiation dose in this group of children undergoing CTCA.AIM To audit the radiation dose of CTCA in children with KD.METHODS Study(December 2013-February 2018)was performed on dual source CT scanner using adaptive prospective electrocardiography-triggering.The dose length product(DLP in milligray-centimeters-mGy.cm)was recorded.Effective radiation dose(millisieverts-mSv)was calculated by applying appropriate age adjusted conversion factors as per recommendations of International Commission on Radiological Protection.Radiation dose was compared across the groups(0-1,1-5,5-10,and>10 years).RESULTS Eighty-five children(71 boys,14 girls)with KD underwent CTCA.The median age was 5 years(range,2 mo-11 years).Median DLP and effective dose was 21 mGy.cm,interquartile ranges(IQR)=15(13,28)and 0.83 mSv,IQR=0.33(0.68,1.01)respectively.Mean DLP increased significantly across the age groups.Mean effective dose in infants(0.63 mSv)was significantly lower than the other age groups(1-5 years 0.85 mSv,5-10 years 1.04 mSv,and>10 years 1.38 mSv)(P<0.05).There was no significant difference in the effective dose between the other groups of children.All the CTCA studies were of diagnostic quality.No child required a repeat examination.CONCLUSION CTCA is feasible with submillisievert radiation dose in most children with KD.Thus,CTCA has the potential to be an important adjunctive imaging modality in children with KD.

Multislice computed tomography angiography in the diagnosis of coronary artery disease

Multislice CT angiography represents one of the most exciting technological revolutions in cardiac imaging and it has been increasingly used in the diagnosis of coronary artery disease. Rapid improvements in multislice CT scanners over the last decade have allowed this technique to become a potentially effective alternative to invasive coronary angiography in patients with suspected coronary artery disease. High diagnostic value has been achieved with multislice CT angiography with use of 64- and more slice CT scanners. In addition, multislice CT angiography shows accurate detection and analysis of coronary calcium, characterization of coronary plaques, as well as prediction of the disease progression and major cardiac events. Thus, patients can benefit from multislice CT angiography that provides a rapid and accurate diagnosis while avoiding unnecessary invasive coronary angiography procedures. The aim of this article is present an overview of the clinical applications of multislice CT angiography in coronary artery disease with a focus on the diagnostic accuracy of coronary artery disease; prognostic value of coronary artery disease with regard to the prediction of major cardiac events; detection and quantification of coronary calcium and characterization of coronary plaques. Limitations of multislice CT angiography in coronary artery disease are also briefly discussed, and future directions are highlighted.

Clinical characteristics of different computed tomography coronary angiography plaque properties in patients with coronary artery disease

Objective: To study the clinical characteristics of different computed tomography coronary angiography (CTCA) plaque properties in patients with coronary artery disease. Methods:Patients who were diagnosed with coronary artery disease in Ankang Central Hospital between February 2015 and March 2017 were selected and divided into soft plaque group, mixed plaque group and calcified plaque group according to the plaque properties judged by CTCA examination, and healthy volunteers who received physical examination in Ankang Central Hospital during the same period were selected as control group. The serum levels of material metabolism indexes, cytokines as well as collagen synthesis and degradation indexes of the four groups were measured. Results: Serum UA, Hcy, PCSK9, LDL-C, GDF-15, CXCL5, hs-CRP, RANTES, IL-6, MMP1, ST2, CysC and I-CTP levels of soft plaque group, mixed plaque group and calcified plaque group were significantly higher than those of control group, serum UA, Hcy, PCSK9, LDL-C, GDF-15, CXCL5, hs-CRP, RANTES, IL-6, MMP1, ST2, CysC and I-CTP levels of soft plaque group and mixed plaque group were significantly higher than those of calcified plaque group, and serum UA, Hcy, PCSK9, LDL-C, GDF-15, CXCL5, hs-CRP, RANTES, IL-6, MMP1, ST2, CysC and I-CTP levels of soft plaque group were significantly higher than those of mixed plaque group. Conclusion: CTCA can accurately determine the plaque properties and evaluate the disorder of material metabolism, cytokine secretion as well as collagen synthesis and degradation during the change of plaque properties in patients with coronary artery disease.

Machine learning for diagnosis of coronary artery disease in computed tomography angiography:A survey

Coronary artery disease(CAD)has become a major illness endangering human health.It mainly manifests as atherosclerotic plaques,especially vulnerable plaques without obvious symptoms in the early stage.Once a rupture occurs,it will lead to severe coronary stenosis,which in turn may trigger a major adverse cardiovascular event.Computed tomography angiography(CTA)has become a standard diagnostic tool for early screening of coronary plaque and stenosis due to its advantages in high resolution,noninvasiveness,and three-dimensional imaging.However,manual examination of CTA images by radiologists has been proven to be tedious and time-consuming,which might also lead to intra-and interobserver errors.Nowadays,many machine learning algorithms have enabled the(semi-)automatic diagnosis of CAD by extracting quantitative features from CTA images.This paper provides a survey of these machine learning algorithms for the diagnosis of CAD in CTA images,including coronary artery extraction,coronary plaque detection,vulnerable plaque identification,and coronary stenosis assessment.Most included articles were published within this decade and are found in the Web of Science.We wish to give readers a glimpse of the current status,challenges,and perspectives of these machine learning-based analysis methods for automatic CAD diagnosis.

Simultaneous Compression of the Celiac Trunk, Superior Mesenteric Artery, and Renal Arteries by the Median Arcuate Ligament: About One Case

Median arcuate ligament syndrome (MALS), is a rare abdominal vascular compression syndrome caused by the compression of the proximal celiac trunk by the median arcuate ligament. According to many authors, a low insertion of the diaphragmatic crura or an abnormally high origin of the celiac trunk from the aorta can cause compression of the celiac artery. Usually, patients with MALS are asymptomatic. Computed tomography (CT) angiography of the abdomen is the main imaging modality to confirm the diagnosis. The coexistence of celiac trunk and superior mesenteric artery compression by the median arcuate ligament is rarely described in the literature. To our knowledge, until now, a simultaneous combination of three abdominal vascular compressions by the median arcuate ligament has never been described. From this case, we report a simultaneous compression of the celiac trunk, superior mesenteric artery, and renal arteries by the median arcuate ligament.

Computed tomography angiographic study of surgical anatomy of thyroid arteries:Clinical implications in neck dissection

BACKGROUND The course and variations of thyroid arteries must be understood by surgeons to prevent bleeding during operative procedures of the thyroid gland.There is limited scientific literature regarding the radiological anatomy of thyroid arteries in this geographical area,the Garhwal region of Sub-Himalayan belt,which is considered to be the endemic belt of goiter.Computed tomography angiography provides a three-dimensional orientation of the vascular and surgical anatomy of the entire cervical region.AIM To estimate the proportion of variation in origin of thyroid arteries using Computed Tomography Angiography.METHODS Using Computed Tomography Angiography,the presence and origin of the superior thyroid artery,inferior thyroid artery,and thyroid ima artery were observed and assessed.RESULTS Out of total 210 subjects,superior thyroid artery was seen to be emerging from external carotid artery in 77.1%cases.The artery was found to be originating at the level of bifurcation of common carotid artery in 14.3%cases,whereas in 8.6%cases,it emerged as a direct branch of the common carotid artery.Similarly,the inferior thyroid artery was observed to be emerging from thyrocervical trunk,subclavian artery and vertebral artery in 95.7%cases,3.3%and 1%cases,respectively.Thyroid ima artery was also reported in a subject,arising from the brachiocephalic trunk.CONCLUSION To avoid vascular injuries,excessive and uncontrollable bleeding,intra-operative difficulties,and post-operative issues,it is imperative for surgeons to be aware of the course and variations of thyroid arteries。

Feasibility and accuracy of coronary imaging in elderly patients using the 64-row multi-detector computed tomography: a correlation study with conventional coronary angiography

Background Elderly patients generally have higher occurrence of coronary calcification, increased heart rate and difficulty with prolonged breath-holding. The aim of our study was to investigate the feasibility and accuracy of using 64-row multi-detector computed tomography (MDCT) in the assessment of coronary artery stenoses in elderly patients. Methods One hundred and fifty two patients with suspected or known coronary artery disease were divided into 4 groups according to their age (Group A: 40-49 years,n=34; Group B: 50-59 years, n=57; Group C: 60-69 years, n=48; Group D: 70 years and above; n=13). Coronary CT angiography (CTA) using a 64-row MDCT was performed and the findings were compared with that of conventional coronary angiography (CCA).Using axial images, multi-planar reconstructions (MPR) and maximum intensity projections (MIP), coronary segments of lumen diameter = 1.5mm were analyzed for the presence of significant stenosis (= 50% ). Results Percentages of poor image quality from coronary CTA preventing reliable correlations with CCA were 21%, 14%, 19% and 62% in Groups A to D respectively. Patients in Group D had significantly higher calcium scores compared with the other groups (P＜0.001). In patients where CTA images were of acceptable quality, percentages of accurate correlations with CCA were 89.8%, 93.4%, 86.6% and 78.0% for Groups A to D respectively.There were no significant difference in serum creatinine, heart rate and contrast volume between the 4 groups. Conclusions The 64-row MDCT coronary angiography was less accurate and feasible for patients aged 70 years or above due to heavy coronary calcification and inability to perform a satisfactory breath-hold. However, a high diagnostic accuracy with the MDCT is possible in patients aged less than 70 years.

Reproducibility of thrombus volume quantification in multicenter computed tomography pulmonary angiography studies

AIM To evaluate reproducibility of pulmonary embolism(PE) clot volume quantification using computed tomography pulmonary angiogram(CTPA) in a multicenter setting.METHODS This study was performed using anonymized data in conformance with HIPAA and IRB Regulations(March 2015-November 2016). Anonymized CTPA data was acquired from 23 scanners from 18 imaging centers using each site's standard PE protocol. Two independent analysts measured PE volumes using a semi-automated region-growing algorithm on an FDA-approved image analysis platform. Total thrombus volume(TTV) was calculated per patient as the primary endpoint. Secondary endpoints were individual thrombus volume(ITV), Qanadli score and modified Qanadli score per patient. Inter-and intra-observer reproducibility were assessed using intra-class correlation coefficient(ICC) and BlandAltman analysis. RESULTS Analyst 1 found 72 emboli in the 23 patients with a mean number of emboli of 3.13 per patient with a range of 0-11 emboli per patient. The clot volumes ranged from 0.0041-47.34 cm3(mean +/-SD, 5.93 +/-10.15 cm3). On the second read, analyst 1 found the same number and distribution of emboli with a range of volumes for read 2 from 0.0041 – 45.52 cm3(mean +/-SD, 5.42 +/-9.53 cm3). Analyst 2 found 73 emboli in the 23 patients with a mean number of emboli of 3.17 per patient with a range of 0-11 emboli per patient. The clot volumes ranged from 0.00459-46.29 cm3(mean +/-SD, 5.91 +/-10.06 cm3). Inter-and intraobserver variability measurements indicated excellent reproducibility of the semi-automated method for quantifying PE volume burden. ICC for all endpoints was greater than 0.95 for inter-and intra-observer analysis. Bland-Altman analysis indicated no significant biases.CONCLUSION Semi-automated region growing algorithm for quantifying PE is reproducible using data from multiple scanners and is a suitable method for image analysis in multicenter clinical trials.

NON-INVASIVE IMAGING OF CORONARY ARTERY WITH 16-SLICE SPIRAL COMPUTED TOMOGRAPHY

To evaluate the value of 16-slice spiral CT in the demonstration of coronary artery and in the diagnose of coronary artery stenosis. Methods Plain and enhanced CT scans were performed with a 16-slice CT scanner (Sensation 16, Siemens, Germany) in 230 patients with suspected coronary heart disease (CHD). Parameters of the plain scan were: 120 kV, 133 mA, slice col-limation 16 mm×1.5 mm, rotation time 0.42 seconds, increment 1.5 mm, and slice width 3 mm. Parameters of the enhanced scan were: 120 kV, 500 mA, slice collimation 16 mm×0.75 mm, rotation time 0.42 seconds, increment 0.5 mm, and slice width 1 mm. Enhanced CT scan was performed with a rapid intravenous injection of 100 mL iothalamate meglumine (Ultravist) (370 mgI/mL) or Omnipaque (350 mgI/mL) and 30 mL 0.9% NaCl chaser bolus at a flow rate of 3.5 mL/s. Calcium scoring with plain scan images and two and three dimensional reconstruction with enhanced scan images were made in all cases, among which 30 cases underwent conventional coronary angiography. Demonstration of coronary arteries and their stenosis were evaluated and the factors that might influence the image quality were analyzed. Results Coronary calcium scores were calculated and coronary artery was demonstrated in our study. In the evaluationof image quality with volume rendering technique (VRT) images, 78.3% of the images were of the first class, 12.2% the sec-ond class, and 9.6% the third class. Multi-planar reconstruction (MPR) and maximal intensity projection (MIP) were better than VRT in the demonstration of small branches. The image quality was related to the heart rate, with or without arrhythmia, and breath-hold ability of patients. Comparative study of the stenosis of coronary arteries in 30 cases showed that the sensi-tivity and specificity of 16-slice coronary CT angiography (CTA) to diagnose significant stenosis were 95.8% and 94.8% resp-ectively. Conclusion As a non-invasive and quick method, 16-slice coronary CTA is sensitive and specific to diagnose the stenosis of coronary arteries and can be used as a screening method in the diagnosis of CHD.

Comparison of 16 slice multi-detector computed tomography and breath hold 3D magnetic resonance angiography in the detection of coronary stenosis

Objective To compare 16-slice multi-detector spiral computed tomography (MDCT) and breathhold 3D magnetic resonance (MR) coronary angiography in the visualization of coronary arteries and the accuracy of detecting significant (＞ 50%) coronary stenoses in patients with suspected coronary artery disease. Methods Forty patients were examined by 16-slice CT (GE, Lightspeedl6)and MR (GE,Twinspeed) within 3 days; 31 of them underwent conventional coronary angiography (CAG) within 2 weeks after CT and MR scan. CT was performed with 16× 1.25 mm detector collimation, 0.5 s rotation time and images were reconstructed at 60%-75% of the cardiac cycle. MR was performed with breath hold 3D FIESTA (TR4.0 ms, TE1.7 ms, flip angle 65, slice thickness 3 mm, FOV 280 mm, matrix 256× 192). Mean heart rate was 63 ± 5.8 bpm and β-blocker was used in 24 patients. MR and CT image quality was evaluated in 9 coronary segments (RCA1, RCA2, RCA3, LM, LAD1, LAD2, LAD3, LCX1, LCX2) using a four-point grading scale.Sensitivity, specificity, positive predictive value, negative predictive value and accuracy were calculated for detection of significant stenosis using CAG as the gold standard. Results 16-slice CT showed higher image quality in most coronary segments except RCA2.Forty-three segments were diagnosed as significant stenosis by CAG, 36 and 27 of these were correctly detected by CT and MR respectively. Sensitivity, specificity, positive predictive value, and negative predictive value of 16-slice CT and MR for detecting significant stenosis were 83 %, 84 %, 49 %, 97 % and 63 %, 90 %, 55 %, 93 %, respectively. Conclusion Sixteen-slice CT showed higher image quality in most coronary segments excepted for middle RCA. 16-slice CT had higher sensitivity than MR for detection of coronary significant stenosis, whereas MR had higher specificity than CT. Both CT and MR showed high negative predictive value,which is useful for excluding coronary stenosis in symptomatic patients.

Evaluation of changes of intracranial blood flow after carotid artery stenting using digital subtraction angiography flow assessment

AIM: To evaluate the changes of intracranial blood flow after carotid artery stenting(CAS), using the flow assessment application "Flow-Insight", which was developed in our department.METHODS: Twenty patients treated by CAS participated in this study. We analyzed the change in concentration of the contrast media at the anterior-posterior and profile view image with the flow assessment application "Flow-Insight". And we compared the results with N-isopropyl-p-[123I] iodoamphetamine-single-photon emission computed tomography(IMP SPECT) performed before and after the treatment. RESULTS: From this study, 200% of the parameter "blood flow" change in the post/pre-treatment is suggested as the critical line of the hyperperfusion syndrome arise. Although the observed blood flow increase in the digital subtraction angiography system did not strongly correlate with the rate of increase of SPECT, the "Flow-Insight" reflected the rate of change of the vessels well. However, for patients with reduced reserve blood flow before CAS, a highly elevated site was in agreement with the site analysis results. CONCLUSION: We concluded that the cerebral angiography flow assessment application was able to more finely reveal hyperperfusion regions in the brain after CAS compared to SPECT.

Relation between Epicardial Adipose Tissue Thickness Assessed by Multidetector Computed Tomography and Significance of Coronary Artery Disease

Objective: To evaluate the relation between epicardial adipose tissue (EAT) thickness and also pericoronary fat assessed by Multidetector Computed Tomography (MDCT) with both calcium score and significance of coronary artery disease. Background: Epicardial adipose tissue (the visceral fat of the heart present under the visceral layer of the pericardium) has the same origin of abdominal visceral fat, which is known to be strongly related to the development of coronary artery atherosclerosis. Multidetector CT (MDCT) provides an accurate and reproducible quantification of EAT due to its high spatial and temporal resolution. Patients and Methods: The current study included 70 patients with low-intermediate probability of coronary artery disease. All patients were subjected to 256 Multidetectors CT to assess EAT thickness, the mean thickness of the pericoronary fat surrounding the three coronary arteries and coronary calcium score. Also coronary CT angiography was done and patients were then divided into 3 groups according to significance of coronary atherosclerosis: Group 1: No atherosclerosis (20 patients), Group 2: Non obstructive atherosclerosis (luminal narrowing less than 50% in diameter) (25 patients), Group3: Obstructive atherosclerosis (luminal narrowing ≥ 50%) (25 patients). Results: The mean EAT thickness and the mean pericoronary fat thickness were significantly higher in patients with obstructive coronary artery disease (CAD) with stenosis > 50% (group 3) compared to other groups with normal coronaries or non obstructive (CAD). ROC curve was used to define the best cut off value of the thickness of both EAT and pericoronary fat in predicting the obstructive CAD group which was ≥7.2 and 12.6 mm for epicardial and pericoronary fat respectively. Also there is a positive correlation between both epicardial adipose tissue and pericoronary fat thickness and the coronary calcium score. Conclusion: EAT thickness and pericoronary fat thickness can be used in predicting the significance of coronary artery disease.

Triple rule-out computed tomography angiography:Evaluation of acute chest pain in COVID-19 patients in the emergency department

BACKGROUND The aim of this study was to define clinical evidence supporting that triple ruleout computed tomography angiography(TRO CTA)is a comprehensive and feasible diagnostic tool in patients with novel coronavirus disease 2019(COVID-19)who were admitted to the emergency department(ED)for acute chest pain.Optimizing diagnostic imaging strategies in COVID-19 related thromboembolic events,will help for rapid and noninvasive diagnoses and results will be effective for patients and healthcare systems in all aspects.AIM To define clinical evidence supporting that TRO CTA is a comprehensive and feasible diagnostic tool in COVID-19 patients who were admitted to the ED for acute chest pain,and to assess outcomes of optimizing diagnostic imaging strategies,particularly TRO CTA use,in COVID-19 related thromboembolic events.METHODS TRO CTA images were evaluated for the presence of coronary artery disease,pulmonary thromboembolism(PTE),or acute aortic syndromes.Statistical analyses were used for evaluation of significant association between the variables.A two tailed P-value<0.05 was considered statistically significant.RESULTS Fifty-three patients were included into the study.In 31 patients(65.9%),there was not any pathology,while PTE was diagnosed in 11 patients.There was no significant relationship between the rates of pathology on CTA and history of hypertension.On the other hand,the diabetes mellitus rate was much higher in the acute coronary syndrome group,particularly in the PTE group(8/31=25.8%vs 6/16=37.5%,P=0.001).The rate of dyslipidemia was significantly higher in the group with pathology on CTA while compared to those without pathology apart from imaging findings of the pneumonia group(62.5%vs 38.7%,P<0.001).Smoking history rates were similar in the groups.Platelets,D-dimer,fibrinogen,C-reactive protein,and erythrocyte sedimentation rate values were higher in COVID-19 cases with additional pathologies.CONCLUSION TRO CTA is an effective imaging method in evaluation of all thoracic vascular systems at once and gives accurate results in COVID-19 patients.

Semi-automated carotid lumen segmentation in computed tomography angiography images

Carotid artery stenosis causes narrowing of carotid lumens and may lead to brain infarction. The purpose of this study was to develop a semi-automated method of segmenting vessel walls, surrounding tissues, and more importantly, the carotid artery lumen by contrast computed tomography angiography（CTA） images and to define the severity of stenosis and present a three-dimensional model of the carotid for visual inspection. In vivo contrast CTA images of 14 patients（7 normal subjects and 7 patients undergoing endarterectomy） were analyzed using a multi-step segmentation algorithm. This method uses graph cut followed by watershed and Hessian based shortest path method in order to extract lumen boundary correctly without being corrupted in the presence of surrounding tissues.Quantitative measurements of the proposed method were compared with those of manual delineation by independent board-certified radiologists. The results were quantitatively evaluated using spatial overlap surface distance indices. A slightly strong match was shown in terms of dice similarity coefficient（DSC） = 0.87±0.08; mean surface distance（Dmsd）= 0.32±0.32; root mean squared surface distance（Drmssd） = 0.49±0.54 and maximum surface distance（Dmax）=2.14±2.08 between manual and automated segmentation of common, internal and external carotid arteries, carotid bifurcation and stenotic artery, respectively. Quantitative measurements showed that the proposed method has high potential to segment the carotid lumen and is robust to the changes of the lumen diameter and the shape of the stenosis area at the bifurcation site. The proposed method for CTA images provides a fast and reliable tool to quantify the severity of carotid artery stenosis.

Novel Approaches for the Use of Cardiac/Coronary Computed Tomography Angiography

Recent developments in the novel imaging technology of cardiac computed tomography(CT)not only permit detailed assessment of cardiac anatomy but also provide insight into cardiovascular physiology.Foremost,coronary CT angiography(CCTA)enables direct noninvasive examination of both coronary artery stenoses and atherosclerotic plaque characteristics.Calculation of computational fl uid dynamics by cardiac CT allows the noninvasive estimation of fractional fl ow reserve,which increases the diagnostic accuracy for detection of hemodynamically signifi cant coronary artery disease.In addition,a combination of myocardial CT perfusion and CCTA can provide simultaneous anatomical and functional assessment of coronary artery disease.Finally,detailed anatomical evaluation of atrial,ventricular,and valvular anatomy provides diagnostic information and guidance for procedural planning,such as for transcatheter aortic valve replacement.The clinical applications of cardiac CT will be extended with the development of these novel modalities.

Aberrations of the Cervical Carotid Artery Which May Be Dangerous in Pharyngeal Surgery—A Computed Tomographic Study

Background: There are recognised variations in the anatomical course of the cervical portion of the internal carotid artery. An aberrant vessel with direct contact to the pharyngeal wall could easily be injured during pharyngeal surgery or may appear as a pharyngeal pseudo mass. Previous anatomical studies predominantly involved older patients. The prevalence of such variations which are at risk of injury during pharyngeal surgery has thus not been established in a general patient population. Material and Methods: The course of the internal carotid artery in relation to the oro and hypopharyngeal walls was retrospectively evaluated bilaterally by simple visual inspection and measurement of the smallest distance between the respective vessels and the adjacent mucosal surface of the pharyngeal wall in 138 consecutive contrast-enhanced computed tomography scans of the neck. Results: 11/138 (7.9%) of patients demonstrated relevant cervical carotid artery aberrations, comprising medial kinking of a vessel with asymmetry of the adjacent pharyngeal lumen and/or an intimate submucous course in the pharyngeal wall with no identifiable separating fat plane. This prevalence increased with age. Simple visual inspection correlated well with the measurement of the smallest distance between an artery and the pharyngeal wall, which was statistically significant (p Conclusions: The prevalence of about 8% in a general patient population is higher than previously recorded in anatomical studies. Prevalence increases with age. Otorhinolaryngologists should be aware of such variation as a risk factor for haemorrhagic complications during pharyngeal surgery and as a differential diagnosis of pharyngeal mass lesions, especially in older patients. Modern contrast-enhanced CT allows identification and characterisation of any surgically relevant variant vascular anatomy in the pre-operative work-up.

R-I subtype single right coronary artery with congenital absence of left coronary system: A case report

BACKGROUND Isolated single coronary artery is a rare congenital anomaly.R-I subtype single coronary artery is even rarer.In this subtype,a very large right coronary artery extends in the coronary sulcus to the anterior base of the heart where it produces the left anterior descending coronary artery.Currently,only a few case reports are available in the literature for this anomaly.CASE SUMMARY Here,we report the case of a 62-year-old woman who presented to the cardiology clinic with decreased exercise tolerance and poor blood pressure control.The patient underwent coronary angiography(CAG)and emission computed tomography(ECT).CAG images revealed a single gigantic right coronary artery(R-I type)arising from the right coronary sinus with branches supplying the left coronary territory.The ECT results confirmed myocardial ischemia at the location of the absent left coronary artery.The ECT findings confirmed that ischemia was consistent with the vascular loss location in CAG images.In such anomalies,there is a compensatory widening of the coronary artery lumen.Medical treatment was administered,and the patient was discharged.CONCLUSION Isolated single coronary arteries are associated with ischemia and potentially fatal acute coronary events.Hence,controlling risk factors is critical.