Multiple Detector Computed Tomography Research Articles

Is there an association between left atrial outpouching structures and recurrence of atrial fibrillation after catheter ablation?

ObjectiveThe aim of this study was to investigate the impact of left atrial diverticula (LADs), left sided septal pouches (LSSPs) and middle right pulmonary veins (MRPVs) on recurrent atrial fibrillation (rAF) in patients undergoing laser pulmonary vein isolation procedure (PVI).Material and methodsThis retrospective study enrolled 139 patients with pre-procedural multiple detector computed tomography (MDCT) imaging and 12 months follow-up examination. LADs, LSSPs and MRPV were identified by two radiologists on a dedicated workstation using multiplanar reconstructions and volume rendering technique. Univariate and bivariate regression analyses with patient demographics and cardiovascular risk factors as covariates were performed to reveal independent factors associated with rAF.ResultsLADs were recorded in 41 patients (29%), LSSPs in 20 (14%) and MRPVs in 15 (11%). The right anterosuperior wall of the left atrium was the most prevalent location of LADs (68%). rAF occured in 20 patients, thereof, 15 exhibited an outpouching structure of the left atrium (LAD: 9, LSSP: 2 and MRPV: 3). Presence of an LAD (HR: 2.7, 95%CI: 1.0–8.4, p = 0.04) and permanent AF (HR: 4.8, 95%CI: 1.5–16.3, p = 0.01) were independently associated with rAF.ConclusionsLAD, LSSP and MRPV were common findings on pre-procedural cardiac computed tomography. LADs were revealed as potential independent risk factor of rAF, which might be considered for treatment planning and post-treatment observation.

Relationship between the coronary artery calcium quantification and gut microbiota composition in subjects without previous cardiovascular disease: A pilot study

AimsTo investigate the relationship between gut microbiota composition and the presence of coronary atherosclerosis assessed by coronary artery calcium (CAC) quantification in individuals without previous cardiovascular disease (CVD). MethodsWe included 20 patients over 18 years of age with no history of CVD who underwent multiple detector-computed tomography (MDCT). From each patient, a stool sample was obtained to characterize gut microbiota composition by sequencing bacterial 16S ribosomal RNA gene. In addition, circulating levels of TNF-α and IL-1β, as well as trimethylamine N-oxide (TMAO) were determined in plasma samples by automated ELISA and capillary gas chromatography-mass spectrometry, respectively. ResultsThe mean age of patients was 63.5 years and 60% were women. Half of patients had CAC > 100 (Agatston score), and were characterized by a higher abundance of the phylum Proteobacteria, mainly of bacteria belonging to the families Enterobacteriaceae, Pasteurellaceae, Erwiniaceae, Vibrionaceae and Morganellaceae, than patients with a CAC ≤ 100. Moreover, bacterial genera identified as biomarkers, such as Enterobacter, Escherichia/Shigella y Klebsiella, were positively associated with inflammation levels and with TMAO production. ConclusionsOur data shows a gut microbiota profile associated with the presence of coronary calcium in patients without previous CVD. Although there are no strategies to decrease the amount of coronary calcium, gut microbiota is highly malleable by several factors. The possibility of preventing and even intervening CVD progression through strategies targeted gut microbiota is a very attractive idea that deserves further studies.

Relación entre la cuantificación de calcio coronario y la composición de la microbiota intestinal en sujetos sin enfermedad cardiovascular previa: estudio piloto

AimTo investigate the relationship between gut microbiota composition and the presence of coronary atherosclerosis assessed by coronary artery calcium (CAC) quantification in individuals without previous cardiovascular disease (CVD). MethodsWe included 20 patients over 18 years of age with no history of CVD who underwent multiple detector-computed tomography. From each patient, a stool sample was obtained to characterize gut microbiota composition by sequencing bacterial 16S ribosomal RNA gene. In addition, circulating levels of TNF-α and IL-1β, as well as trimethylamine N-oxide (TMAO) were determined in plasma samples by automated ELISA and capillary gas chromatography-mass spectrometry, respectively. ResultsThe mean age of patients was 63.5 years and 60% were women. Half of patients had CAC >100 (Agatston score), and were characterized by a higher abundance of the phylum Proteobacteria, mainly of bacteria belonging to the families Enterobacteriaceae and than patients with a CAC ≤ 100. Moreover, bacterial genera identified as biomarkers, such as Enterobacter, Escherichia/Shigella y Klebsiella, were positively associated with inflammation levels and with TMAO production. ConclusionOur data shows a gut microbiota profile associated with the presence of coronary calcium in patients without previous CVD. Although there are no strategies to decrease the amount of coronary calcium, gut microbiota is highly malleable by several factors. The possibility of preventing and even intervening CVD progression through strategies targeted gut microbiota is a very attractive idea that deserves further studies.

Left Atrial Volume Correlates with Mitral Annulus Size: An MDCT Study

Aim: Although the association between left ventricular dilation and mitral annulus dilation is well understood, the potential variation in the size of the mitral annulus during dilation of the left atrium is currently unknown. In order to investigate the link between the two variables, we used multidetector computed tomography (MDCT) and looked at patients who had a dilated left atrium, assessing if the mitral valve also dilates. Materials and Methods: The study included 107 patients with paroxysmal and persistent atrial fibrillation, in whom catheter ablation was performed using pulmonary vein isolation ± atrial substrate modification. Eighty patients were male (74.8%), with a mean age of 55.8 years (±9.87 with a minimum age of 26 years and a maximum age of 79 years), of which 57.1% had paroxysmal AF and the rest had persistent fibrillation. All the patients underwent multiple-detector CT (MDCT) with contrast medium before the ablation. CT images were integrated into the three-dimensional mapping system CARTO 3, after which the diameters of the mitral annulus, area, and circumference were measured. Left atrial size was evaluated by measuring the diameters, area, and volume. Results: The left atrial area was 247 ± 65.7 cm2 and the left atrial volume was 139 ± 56.3 mL. The transverse mitral annulus (MA) was 29.9 ± 5.3 mm and the longitudinal diameter was 41.9 ± 7.6 mm. The MA circumference and area were 15.0 ± 3.5 cm and 14.2 ± 4.6 cm2, respectively. The following statistically significant correlation was identified between the dimensions of the mitral annulus and the diameters of the left atrium: the transverse mitral annulus correlates with the antero-posterior (AP) LA diameter (R = 0.594, p < 0.01) and the longitudinal MA diameter correlates with the latero-lateral (LL) LA diameter (R = 0.576, p < 0.01). Furthermore, the MA area correlates with the LA volume (R = 0.639, p < 0.001). Conclusions: The volume of the left atrium correlates with the area of the mitral annulus. In patients with paroxysmal and persistent AF, an increase in left atrial dimensions is further associated with an increase in mitral valve dimensions.

Leiomyosarcoma of the Renal Pelvis

Leiomyosarcoma of the renal pelvis is an extremely rare mesenchymal tumor of the kidney. A 68-year-old male presented to the Urosurgery Department with hematuria, right flank pain, and burning micturition. On ultrasonography of the abdomen and pelvis, a soft tissue density mass lesion involving right renal pelvis and lower calyx measuring 2.5 cm × 1.5 cm × 1.4 cm in the right renal calculi, mild right hydronephrosis and hydroureter, mobile vesicle calculus, and mild prostatomegaly with changes of cystitis with significant postvoid residue were noted. The primary diagnosis based on imaging findings computed tomography (CT) abdomen and pelvis multiple detector CT scan, was given as suggestive of malignant tumor of the right kidney and pelvis. The right radical nephrectomy was done. On histopathology, it was confirmed as leiomyosarcoma of the right renal pelvis. We report an extremely rare tumor leiomyosarcoma of the renal pelvis for its clinical, radiological, and histopathological findings.

How far is the left circumflex coronary artery from the mitral annulus?

The relationship between the distance from the mitral annulus to the left circumflex coronary artery (LCX) and iatrogenic LCX injury has been questioned. This study was designed to determine the high-risk sites of LCX injury with an anatomical approach using multiple detector-computed tomography (MDCT) scanning taken before mitral valve annuloplasty (MVA). The purpose of this study is to prevent LCX injury in patients unable to receive MDCT before mitral valve surgery. In 2018, we performed MVA on 59 patients, 52 of whom had undergone preoperative MDCT scanning. We retrospectively analyzed the MDCT images of these 52 patients and measured the shortest distance from the mitral annulus to the LCX in three dimensions. Also, we divided the mitral annulus into 12 clockwise areas (A0-A11) to identify the exact location. The site of closest proximity and their numbers of patients were as follows: A6, 1 patient; A8, 2 patients; A9, 32 patients; and A10, 17 patients. Nine (17.3%) of the 52 patients had the shortest distance of less than 2mm. The shortest distance according to the dominance of coronary artery showed no significant difference (p = 0.81). The site of closest proximity from the mitral annulus to the LCX was concentrated on the A8 to A10 areas and it is an interesting result that as many as 17% of patients have their coronary arteries less than 2mm away from the annulus.

Pancreatic neuroendocrine tumors (pNETs): the predictive value of MDCT characteristics in the differentiation of histopathological grades.

To investigate the correlation between multiple detector computed tomography (MDCT) features of pancreatic neuroendocrine tumors (pNETs) and histopathologic grade and find valuable imaging criteria for grade prediction. MDCT of 61 patients with 65 masses, which pNETs were approved histopathologically, underwent revision retrospectively. Each MDCT was evaluated for various radiologic characteristics. Absolute and relative (R: tumor/pancreas, D: tumor-pancreas) tumor enhancements were calculated in multiple post contrast phases. 61 patients [mean age = 50.70 ± 14.28 y/o and 30(49.2%) were male] were evaluated and classified into 2 groups histopathologically: G1: 32 (49.2%) and G2,3: 33 (50.8%). Significant relationships were observed between histopathologic tumor grade regarding age (p = 0.006), the longest tumor size (p = 0.006), presence of heterogeneity (p < 0.0001), hypodense foci in delayed phase (p = 0.004), lobulation (p = 0.002), vascular encasement (p < 0.0001), adjacent organ invasion (p = 0.01), presence (p < 0.0001) and number (0.02) of liver metastases, presence of lymphadenopathy with short axis of more than 10mm (LAP) (p = 0.008), pathologic lymph node size (p = 0.004), relative (R and D) (p = 0.05 and 0.02, respectively), and percentage of arterial hyper-enhancing area (p = <0.0001). Tumor grades, however, had no significant relationship with gender, tumor location, tumor outline, calcification, cystic change, or pancreatic (PD) or biliary duct (BD) dilation (p = 0.21, 0.60, 0.05, 0.05 1, 0.10, and 0.51, respectively). Then, we suggested a novel imaging criteria consisting of six parameters (tumor size > 33mm, relative (R) tumor enhancement in arterial phase ≤ 1.33, relative (D) tumor enhancement in arterial phase ≤ 16.5, percentage of arterial hyper-enhancing area ≤ 75%, vascular encasement, and lobulation), which specificity and accuracy of combination of all findings (6/6) for predicting G2,3 were 100% and 70.1%, respectively. The highest accuracy (84.21%) was seen in combinations of at least 4 of 6 findings, with 80.00% sensitivity, 87.5% specificity, 83.33% PPV, and 84.85% NPV. We suggested reliable imaging criteria with high specificity and accuracy for predicting the histopathologic grade of pNETs.

Differentiation of Upper Urinary Tract Lesions Using MDCT: Benign Vs Malignant

To evaluate the accuracy of multiple detector computed tomography (MDCT) in differentiating benign and malignant lesions of upper urinary tract (UUT). Fifty-four patients with 55 suspected UUT lesions were included in the study. All patients underwent MDCT scan with nephrographic and excretory phases. The unenhanced phase was also performed in 38 cases. The final diagnosis was made by histology in 48 lesions: 43-after surgery, 5-after biopsy and by MDCT follow-up over at least 15 months in the remaining 7 lesions. The following CT features were evaluated: number of lesions, lesion appearance (mass or wall thickening), presence of calcifications, internal border appearance (smooth or irregular), and size and enhancement (presence or absence). The relationship between imaging characteristics and pathology (benign vs malignant) was assessed with logistic regression, univariable diagnostic accuracy, and with classification and regression tree analysis. Patients with mass morphology had a significantly higher probability of malignancy (odds ratio [OR]: 3.73, 95%CI: 1.02-13.72, p = 0.047) compared to patients with thickened wall morphology. The presence of an irregular internal border was also significantly associated with malignancy (OR: 12.14, 95%CI: 2.95-50.06, p < 0.001). No significant associations were found between malignancy and lesion size (p = 0.29), calcifications (p = 0.93) or enhancement (p = 0.68). Mass morphology and irregular internal border are reliable signs to suggest malignancy in UUT lesions.

Accuracy of radiologic- laparoscopic peritoneal carcinomatosis categorization in the prediction of surgical outcome.

To evaluate the agreement between multiple detector CT (MDCT) and laparoscopy in the preoperative categorization of peritoneal carcinomatosis, and to determine the impact of this categorization on the prediction of cytoreduction status. This prospective study included 80 consecutive females with primary ovarian cancer eligible for cytoreductive surgery (CRS). MDCT and diagnostic laparoscopy were performed prior to surgery for assessment of peritoneal carcinomatosis extent. Based on PCI (peritoneal cancer index) score, carcinomatosis was categorized into three groups. Categorization agreement between CT and laparoscopy was assessed and compared with the intraoperative-histopathologically proven PCI. Impact of PCI categorization on cytoreduction status was also evaluated. The overall agreement between CT and laparoscopy in preoperative peritoneal carcinomatosis categorization was good (K =0.71-0.79) in low category group and excellent in both moderate and large group (interclass correlation coeeficient = 0.89-0.91). (p<0.01) Optimal cytoreduction was achieved in 62/80 (77.5%) patients, PCI < 20 was detected in 48/62 (77.4%), pre-operative PCI < 20 correctly predicted optimal cytoreductive surgery (OCS) in 40/48 (83.3%) cases. Suboptimal cytoreduction was performed in 18/80 (22.5%) patients. PCI > 20 was detected in (10/18) 55.6%, preoperative CT and laparoscopy PCI > 20 correctly predicted SCS in 8/10 (80%) cases. The area under receiver operating characteristic curve showed that PCI cut-off <20 was the best predictor of OCS with an accuracy 85%, sensitivity 97%, specificity 40%, negative predictive value 76%, and positive predictive value 93%. Both laparoscopy and CT are equally effective in pre-operative peritoneal carcinomatosis categorization. PCI < 20 is accurate in the prediction of optimal cytoreduction. More than half of patients with suboptimal cytoreduction had PCI > 20 and interval debulking surgery can be recommended. Both laparoscopy and CT are equally effective in pre-operative peritoneal carcinomatosis categorization. PCI < 20 is accurate in the prediction of optimal cytoreduction. More than half of patients with suboptimal cytoreduction had PCI > 20 and interval debulking surgery can be recommended.

Accuracy of cone-beam computed tomography for syndesmosis injury diagnosis compared to conventional computed tomography

BackgroundSyndesmosis injury can lead to ankle mortise instability and early osteoarthritis. Several multiple detector computed tomography (MDCT) methods for measurement have been developed. Weight-bearing cone beam CT (WB CBCT) is an emerging technique that offers the possibility of upright-position scanning and lower doses. This study sought to assess the diagnostic accuracy of WB CBCT in syndesmose injury compared to MDCT, with instability confirmed via manual testing upon arthroscopic examination. MethodsThree musculoskeletal radiologists with different levels of expertise prospectively analyzed 11 MDCT and eight WB CBCT scans of the same trauma-afflicted ankles with clinical suspicion of syndesmosis lesion over a period of 5 months. They evaluated 10 methods of measurement in both sides. Syndesmosis was considered pathological on arthroscopic examination in four patients. Correlation between readers was evaluated with intra-class correlation testing (p < 0.05 was considered significant). Capacity of discrimination was assessed by area under the curve (AUC) for all methods. ResultsInter-observer agreement was near excellent for both WB CBCT and MDCT for the anterior tibio-fibular (TF) distance (ICC = 0.781 and 0.831, respectively), posterior TF distance (ICC = 0.841 and 0.826), minimal TF distance (ICC = 0.899 and 0.875), and TF surface (ICC = 0.93 and 0.84). AUC were better for MDCT than WB CBCT in assessing syndesmosis instability for: anterior TF distance (ROC = 0.869 vs. 0.555, p = 0.01), minimal TF distance (ROC = 0.883 vs. 0.608, p = 0.02) and antero-posterior fibular translation (ROC = 0.894 vs. 0.467, p = 0.006). ConclusionsMDCT demonstrated better ability to distinguish pathological syndesmosis than WB CBCT, with the antero-posterior fibular translation the best discriminating measurement. The physiological widening of the contralateral syndesmosis occurring with the WB CBCT upright position may explain these results.

Infection of Mycobacterium mageritense at surgical site: A first case report of India

A 27 years old non diabetic, normotensive, female had undergone lower segment caesarean section (LSCS) with tubular ligation. She complained discharge at left side of stitch line after about 5 weeks of operation, and was treated with broad spectrum antibiotics. As she did not improve, first and second debridement was done in January and February 2017 and pyogenic cultures sent were sterile. Later she was advised for Multiple detector computed tomography (MDCT) in March 2017, which revealed accumulations in pre-peritoneal space of urinary bladder posteriorly and reached to anterior wall of uterus. This pus was from multiple sinuses and were sent for mycobacterial cultures which showed growth of MOTT- M.mageritense further identified by MALDI-TOF and supported by molecular technologies. After identification of this Non-tuberculosis mycobacteria (NTM). She was treated for the same and recovered completely after seven months of anti-NTM treatment. This is the first reported case of M. mageritense in skin and soft tissue in India. Literature also reports a few cases around the globe.&#x0D;

Reliability and accuracy of skin-supported surgical templates for computer-planned craniofacial implant placement, a comparison between surgical templates: With and without bony fixation

IntroductionThe purpose is to determine the accuracy of guided implant placement in the orbital, nasal, and auricular region using computer-aided designed stereolithographic skin-supported surgical templates with and without bone fixation pins. Materials and MethodsPreoperatively, cone-beam CT (CBCT) and multiple detector computed tomography (MDCT) scans were acquired from 10 cadaver heads, followed by virtual planning of implants in the orbital margin, auricular region and nasal floor. Surgical skin-supported templates were digitally designed to allow flapless implant placement. Fixation pins were used for stabilization comprising half of all templates in predetermined bone areas. The accuracy of the surgical templates was validated by comparing the achieved implant location to its virtual planned implant position by calculating the linear and angular deviations. ResultsSurgical templates with the use of bone fixation pins produced statistically significant greater implant deviations as compared to the non-fixated surgical templates. ConclusionThe results of this study indicate that significant deviation has to be taken into account when placing cranio-maxillofacial implants using skin-supported surgical templates. Surprisingly, the use of bone-fixated pins worsened the accuracy.

Forensic anthropological standards for cranial sex estimation in Canada: preliminary results

ABSTRACTIn forensic investigations of unknown skeletal remains, a biological profile is used to narrow the pool of potential matches in the missing person’s database; one of the important components of that profile is the accurate estimation of skeletal sex. The current study involves the morphometric quantification of cranial sexual dimorphism in a Canadian population for the specific purpose of developing predictive models for the estimation of sex. The main aim of this study is, therefore, to quantify the accuracy methods of said existing sex estimation models as applied to a Canadian population and thereafter devise population-specific standards. The current study represents the retrospective analysis of 400 (190 female, 210 male) multiple detector computed tomography (MDCT) scans collected from the Sunnybrook Health Sciences Centre in Toronto, Ontario. Preliminary results indicate that current methods of cranial skeletal sex estimation illicit unacceptable classification accuracy rates when applied to this sample.

Combination of the ankle-brachial index and percentage of mean arterial pressure to improve diagnostic sensitivity for peripheral artery disease

The ankle-brachial index (ABI) is a noninvasive method for screening for peripheral artery disease (PAD). However, false-negative findings of the ABI may limit its clinical use. The percentage of mean arterial pressure (%MAP) calculated from pulse volume recording has been reported to predict all-cause mortality. We hypothesized that the %MAP would be helpful to screen for PAD in subjects with a normal ABI. We examined whether using a combination of the ABI and %MAP would provide greater diagnostic sensitivity for PAD than using the ABI alone.In this cross-sectional study, we retrospectively reviewed the medical records of patients who had undergone multiple detector computed tomography (MDCT) angiography of the lower extremities following measurement of the ABI with pulse volume recording. PAD was diagnosed based on MDCT angiography.A total of 215 lower extremities of 114 patients were included in our analyses. An optimal cut-off %MAP value of 42.5% was used to diagnose PAD based on MDCT in patients with an ABI > 0.90. Using a combination of an ABI < 0.90 and a %MAP ≥ 42.5% as diagnostic criteria for PAD resulted in better sensitivity (76.9%) than using the ABI alone (56.5% for an ABI < 0.90 and 63.4% for an ABI < 1.00). Using logistic regression analysis, we found that patients having both an ABI < 0.90 and an ABI > 0.90 with a %MAP ≥ 42.5% had a significantly higher risk of PAD than those having an ABI > 0.90 with a %MAP < 42.5% (odds ratio = 7.165, P = .006; odds ratio = 12.544, P < .001; respectively).Both the sensitivity and specificity were better when using a combination of an ABI ≤ 0.90 and a %MAP ≥ 42.5% than when using a low or borderline ABI. The %MAP is helpful for PAD screening in subjects with an ABI > 0.90.

Electrochemotherapy of cholangiocellular carcinoma at hepatic hilum: A feasibility study

AimWe evaluated feasibility, safety and efficacy of Electrochemotherapy (ECT) in a prospective series of patients with unresectable Perihilar-Cholangiocarcinoma (PHCCA). Patients and methodsFive patients with PHCCA underwent ECT. Three patients underwent percutaneous ECT of a single PHCCA nodule. One patient underwent resection of a nodule in the IV segment and intraoperative ECT of a large PHCCA in the VIII segment. Another patient underwent percutaneous ECT of a large PHCCA recurrence after left lobectomy and RF ablation of a synchronous metastasis in the VI segment.ECT was performed under US guidance. Efficacy was evaluated by contrast-enhanced multiple-detector-computed-tomography (MDCT) 4 weeks after treatment. Follow-up entailed MDCT every 6 months thereafter. ResultsNo major complication occurred. Follow-up ranges from 10 to 30 months. Four weeks post-treatment CT showed complete response in 3 cases. These patients are still alive, and follow-up CT controls demonstrated no local or distant intrahepatic recurrences and no biliary duct dilation in 2 cases and local recurrence at 18 months follow-up control in 1 patient. In the remaining 2 cases, 4-weeks-post-treatment CT showed incomplete response (>90%). In these patients follow-up CT demonstrated local progression of the disease at 6 months. One of them had bilateral external biliary drainages and died because of tumor progression at 16-months-follow-up. The other patient, died at 10 months follow-up for cardiovascular failure not related to the hepatobiliary disease. ConclusionsECT is feasible, safe and effective therapy to improve prognosis and quality of life of patients with unresectable PHCCA.

A case report of pseudoaneurysm of left sinus of Valsalva invaded into the left ventricle with severe aortic regurgitation

BackgroundThe pseudoaneurysms of sinus of Valsalva is an uncommon and serious complication of an infection, trauma, or after cardiac surgery or procedure. Pseudoaneurysms of sinus of Valsalva from left is rare. We describe a case of pseudoaneurysm of the left coronary sinus of Valsalva invaded into the left ventricle (LV) diagnosed by transthoracic echocardiography (TTE), transesophageal ecoccardiography (TEE), and multiple detector computed tomography (MDCT).Case presentationA 44-year-old male patient had New York Heart Association (NYHA) class II / III dyspnea during 4 months. He underwent surgery including aortic valve replacement using mechanical prosthesis, and he was discharged well without significant complications on follow – up TTE and chest computed tomography (CT) post-operative 7 days.ConclusionsWe report this rare case in which a ruptured pseudoaneurysm of sinus of Valsalva into LV with severe AR due to perforation of LCC was successfully-treated.

Dose and slice thickness evaluation with nMAG gel dosimeters in computed tomography

Computed tomography (CT) has been widely used in clinical diagnosis. It is important to estimate radiation dose and perform image quality assurance procedures for CT scans. In this study, nMAG gel dosimeters were used to simultaneously measure the 300-mm weighted CT dose index (CTDI) and slice sensitivity profile (SSP) for multiple detector CT (MDCT). Magnetic resonance imaging (MRI) was performed on the irradiated gel to create R2‒dose response curves for the tube voltages of 120 and 140 kVp. The gel dosimeters were loaded in three home-made cylindrical phantoms to obtain CTDI100 and CTDI300. The full width at half maximum (FWHM) for 2, 5, 10, 14.4, and 38.4-mm slice thicknesses was measured and compared with the result obtained by radiochromic films. The difference in weighted CTDI100 obtained by the gel dosimeter and ionization chamber was less than 1%. The CTDI efficiency at 120 and 140 kVp was in the range of 80.1%–82.5%. The FWHM of SSP measured by the gel dosimeter matched very well with the nominal slice thickness. The use of nMAG gel dosimeters combined with the home-made cylindrical phantoms can provide 300-mm weighted CTDI and slice thickness information, showing potential for quality assurance and clinical applications in MDCT.

Abstract TP182: Coronary Calcium Score Improves Predictability of Asymptomatic Coronary Artery Disease in Non-embolic Ischemic Stroke Patients

Background and purpose: Many patients with ischemic stroke have concomitant coronary artery disease (CAD). Coronary screening is recommended in patients with high risks for CAD. It remains uncertain which group of stroke patients need evaluation for asymptomatic CAD, and which evaluation tool is appropriate for stroke patients. We investigated whether the coronary artery calcium (CAC) scores could predict significant CAD in patients with acute stroke and which stroke patients need a screening test for significant CAD. Methods: Among consecutive stroke patients between September 2011 and August 2013, a total of 1143 patients who underwent multiple detector CT coronary angiography and cerebral angiography were included. Atherosclerotic stenosis ≥ 50% or obstruction was classified as significant stenosis in coronary and cerebral arteries. Patients were grouped into four subgroups on the basis of CAC score: 0, 0.1-99.9, 100-399.9, and ≥ 400. Presence of hypertension, diabetes mellitus, dyslipidemia, and cigarette smoking were considered as risk factors. Results: Of 1143 patients, significant stenosis was detected in 164 patients (14.3%) in the internal carotid artery (ICA), 279 (24.4%) in the vertebrobasilar artery (VBA), and 81 (7.1%) in the both ICA and VBA. Significant coronary artery stenosis in at least one coronary artery was detected in the 398 patients (34.8%). Two or more risk factors and one or more significant stenosis in the ICA or VBA were considered as screening criteria for choosing potential CAD patients according to AUC analysis. As the CAC score increased, odd ratio for significant CAD remarkably increased (2.1678, CI 1.0152 to 4.6290 for CAC score 0, 5.7193 ,CI 2.9192 to 11.2051 for 0 &lt;CAC score &lt; 100 , 15.6351 ,CI 7.8537 to 31.1262 for 100≤CAC score &lt; 400, and 72.2925, CI 33.8979 to 154.1746 for CAC score≥400, respectively, P &lt;0.05 for all). Conclusion: Two or more risk factors and one or more significant stenosis in the ICA or VBA can be used to choose patients with stroke who need to perform a screening test predicting significant CAD. CAC score also can be used as a screening to perform coronary artery evaluation even in the patients without documented cerebral atherosclerosis.

Multidetector CT in detection of troublesome posterior sectoral hepatic duct communicating with cystic duct.

To investigate whether multiple detector CT (MDCT) could detect troublesome aberrant posterior sectoral hepatic duct (PHD) communicating with cystic duct (CD). The most troublesome bile duct anomaly during cholecystectomy is an aberrant PHD communicating with CD. It has been suggested that an unenhanced small duct between Rouviere's sulcus and CD on MDCT could be coincident to an aberrant PHD communicating with CD. A total of 224 patients who underwent laparotomy with complete lymph node dissection in the hepatoduodenal ligament for hepatobiliary or pancreatic tumour were enrolled. Retrospective review of preoperative MDCT images and surgical records was performed. Preoperative MDCT detected 8 (3.6%) unenhanced ducts between Rouviere's sulcus and CD. Surgical records identified 7 (3.1%) cases of aberrant PHD communicating with CD, and all 7 cases showed an unenhanced duct between Rouviere's sulcus and CD on preoperative MDCT imaging. Among the 7 patients, 5 (71%) were without bile duct dilatation. MDCT could detect troublesome aberrant PHD communicating with CD, regardless of the presence or absence of bile duct dilatation. Advances in knowledge: MDCT could detect most troublesome PHD communicating with CD, regardless of the presence or absence of bile duct dilatation.

Primary intestinal lymphangiectasia: Multiple detector computed tomography findings after direct lymphangiography.

To analyse the findings of multiple detector computed tomography (MDCT) after direct lymphangiography in primary intestinal lymphangiectasia (PIL). Fifty-five patients with PIL were retrospectively reviewed. All patients underwent MDCT after direct lymphangiography. The pathologies of 16 patients were confirmed by surgery and the remaining 39 patients were confirmed by gastroendoscopy and/or capsule endoscopy. After direct lymphangiography, MDCT found intra- and extraintestinal as well as lymphatic vessel abnormalities. Among the intra- and extraintestinal disorders, 49 patients had varying degrees of intestinal dilatation, 46 had small bowel wall thickening, 9 had pleural and pericardial effusions, 21 had ascites, 41 had mesenteric oedema, 20 had mesenteric nodules and 9 had abdominal lymphatic cysts. Features of lymphatic vessel abnormalities included intestinal trunk reflux (43.6%, n=24), lumbar trunk reflux (89.1%, n=49), pleural and pulmonary lymph reflux (14.5%, n=8), pericardial and mediastinal lymph reflux (16.4%, n=9), mediastinal and pulmonary lymph reflux (18.2%, n=10), and thoracic duct outlet obstruction (90.9%, n=50). Multiple detector computed tomography after direct lymphangiography provides a safe and accurate examination method and is an excellent tool for the diagnosis of PIL.