Multidetector-row Computed Tomography Research Articles

Efficacy of positron emission tomography in diagnosis of lateral lymph node metastases in patients with rectal Cancer: a retrospective study

BackgroundThe presence of lateral pelvic lymph node (LLN) metastasis is an essential prognostic factor in rectal cancer patients. Thus, preoperative diagnosis of LLN metastasis is clinically important to determine the therapeutic strategy. The aim of this study was to evaluate the efficacy of preoperative positron emission tomography/computed tomography (PET/CT) in the diagnosis of LLN metastasis.MethodsEighty-four patients with rectal cancer who underwent LLN dissection at Osaka University were included in this study. The maximum standardized uptake value (SUVmax) of the primary tumor and LLN were preoperatively calculated using PET/CT. Simultaneously, the short axis of the lymph node was measured using multi-detector row computed tomography (MDCT). The presence of metastases was evaluated by postoperative pathological examination.ResultsOf the 84 patients, LLN metastases developed in the left, right, and both LLN regions in 6, 7, and 2 patients, respectively. The diagnosis of the metastases was predicted with a sensitivity of 82%, specificity of 93%, positive predictive value of 58%, negative predictive value of 98%, false positive value of 7%, and false negative value of 18% when the cutoff value of the LLN SUVmax was set at 1.5. The cutoff value of the short axis set at 7 mm on MDCT was most useful in diagnosing LLN metastases, but SUVmax was even more useful in terms of specificity.ConclusionsThe cutoff value of 1.5 for lymph node SUVmax in PET is a reasonable measure to predict the risk of preoperative LLN metastases in rectal cancer patients.

A comparison of breast and lung doses from chest CT scans using organ-based tube current modulation (OBTCM) vs. Automatic tube current modulation (ATCM).

PurposeThe purpose of this work was to estimate and compare breast and lung doses of chest CT scans using organ‐based tube current modulation (OBTCM) to those from conventional, attenuation‐based automatic tube current modulation (ATCM) across a range of patient sizes.MethodsThirty‐four patients (17 females, 17 males) who underwent clinically indicated CT chest/abdomen/pelvis (CAP) examinations employing OBTCM were collected from two multi‐detector row CT scanners. Patient size metric was assessed as water equivalent diameter (Dw) taken at the center of the scan volume. Breast and lung tissues were segmented from patient image data to create voxelized models for use in a Monte Carlo transport code. The OBTCM schemes for the chest portion were extracted from the raw projection data. ATCM schemes were estimated using a recently developed method. Breast and lung doses for each TCM scenario were estimated for each patient model. CTDIvol‐normalized breast (nDbreast) and lung (nDlung) doses were subsequently calculated. The differences between OBTCM and ATCM normalized organ dose estimates were tested using linear regression models that included CT scanner and Dw as covariates.ResultsMean dose reduction from OBTCM in nDbreast was significant after adjusting for the scanner models and patient size (P = 0.047). When pooled with females and male patient, mean dose reduction from OBTCM in nDlung was observed to be trending after adjusting for the scanner model and patient size (P = 0.085).ConclusionsOne specific manufacturer’s OBTCM was analyzed. OBTCM was observed to significantly decrease normalized breast relative to a modeled version of that same manufacturer’s ATCM scheme. However, significant dose savings were not observed in lung dose over all. Results from this study support the use of OBTCM chest protocols for females only.

Prognostic implications of cardiac damage classification based on computed tomography in severe aortic stenosis.

An echocardiographic staging system of severe aortic stenosis (AS) based on additional extra-valvular cardiac damage has been associated with prognosis after transcatheter aortic valve implantation (TAVI). Multidetector row computed tomography (MDCT) is key in the evaluation of AS patients undergoing TAVI and can potentially detect extra-valvular cardiac damage. This study aimed at evaluating the prognostic implications of an MDCT staging system of severe AS in patients undergoing TAVI. A total of 405 patients (80 ± 7 years, 52% men) who underwent full-beat MDCT prior to TAVI were included. The extent of cardiac damage was assessed by MDCT and classified in five categories; Stage 0 (no cardiac damage), Stage 1 (left ventricular damage), Stage 2 (left atrium and mitral valve damage), Stage 3 (right atrial damage), and Stage 4 (right ventricular damage). Twenty-seven (7%) patients were stratified as Stage 0, 96 (24%) as Stage 1, 152 (38%) as Stage 2, 78 (19%) as Stage 3, and 52 (13%) as Stage 4. During a median follow-up of 3.7 (IQR 1.7-5.5) years, 150 (37%) died. On multivariable Cox regression analysis, cardiac damage Stage 3 (HR vs. Stage 0: 4.496, P = 0.039) and Stage 4 (HR vs. Stage 0: 5.565, P = 0.020) were independently associated with all-cause mortality. The MDCT-based staging system of cardiac damage in severe AS effectively identifies the patients who are at higher risk of death after TAVI.

Preoperative Determination of the Size of the Semitendinosus and Gracilis Tendon by Multidetector Row CT Scanner for Anterior Cruciate Ligament Reconstruction.

Accurately measuring the length and diameter of the hamstring tendon autograft preoperatively is important for planning anterior cruciate ligament (ACL) reconstructive surgery. The purpose of this study was to assess the reliability of three-dimensional computed tomography (3D CT) scanning technique to produce the actual measurement of the gracilis and semitendinosus (GT and ST, respectively) tendon grafts' length and diameter for surgery. Ninety patients were scheduled for ACL reconstruction with hamstring autograft. Before the surgery, patients were examined under the multidetector row CT scanner and the ST and GT tendons were qualitatively measured by a volume-rendering technique. The length of ST and GT was measured with 3D CT compared with the length of the harvested ST and GT. The cross-sectional area (CSA) of ST and GT measured with 3D CT compared with the ST and GT graft diameter. Tendon size measured preoperatively and during surgery were statistically compared and correlated. The GT tendons length and cross-sectional area measured during surgery was both shorter and smaller compared with the ST tendon. GT and ST tendon length were correlated to patients' body index such as the height and weight (p < 0.05). However, the correlation levels were low to medium (r = 0.23-0.49). There was strong correlation between the lengths of GT (r = 0.76; p < 0.001) and ST (r = 0.87; p < 0.001) measured with the 3D CT and tendon length at surgery. There was a moderate correlation between graft diameter measured at surgery and 3D CT cross-sectional area (r = 0.31; p < 0.05). A multidetector row CT scanner can determine the ST and GT tendons' length and diameter. These measurements can be used for preoperative planning to help determine the surgical method and counsel patients on appropriate graft choices prior to surgery.

Pancreatic acinar cell carcinoma with extension into the main pancreatic duct: a case report

BackgroundPancreatic acinar cell carcinoma (PACC) is a rare exocrine malignant tumor. Its widespread intraductal extension into the main pancreatic duct (MPD) is also rare.Case presentationWe report the case of a 71-year-old man with PACC with MPD extension. The patient was assessed with laboratory and radiographic investigations that facilitated a preoperative diagnosis. Endoscopic ultrasonography (EUS) and dynamic thin-slice multi-detector row computed tomography (MDCT) were useful for determining the resection line of the pancreas. EUS-guided fine needle aspiration (EUS-FNA) was also helpful in determining the tumor biology and treatment strategy. Distal pancreatectomy was performed. The MPD was occupied by the tumor 35 mm downstream and 5 mm upstream. Histopathologically, the pancreatic tail tumor extended continuously into the MPD. The tumor was solid with cells showing eosinophilic and granular cytoplasm, indicating the diagnosis of PACC. This is an interesting case of PACC with intraductal extension into the MPD. We discuss the possible mechanisms of tumor extension in this rare case together with a review of the literature.ConclusionsWe describe a rare pancreatic acinar cell carcinoma that could be adequately treated using preoperative precise imaging and histopathological evaluations. When an intraductal tumor extension in the MPD is encountered, the diagnosis of a rare pancreatic tumor should be considered, as in our case.

Combination of dirty mass volume and APACHE II score predicts mortality in patients with colorectal perforation

Background“Dirty mass” is a specific computed tomography (CT) finding that is seen frequently in colorectal perforation. The prognostic significance of this finding for mortality is unclear.MethodsFifty-eight consecutive patients with colorectal perforation who underwent emergency surgery were retrospectively reviewed in the study. Dirty mass identified on multi-detector row CT (MDCT) was 3D-reconstructed and its volume was calculated using Ziostation software. Dirty mass volume and other clinical characteristics were compared between survivor (n = 45) and mortality groups (n = 13) to identify predictive factors for mortality. Mann–Whitney U test and Χ2 test were used in univariate analysis and logistic regression analysis was used in multivariate analysis.ResultsDirty mass was identified in 36/58 patients (62.1%) and located next to perforated colorectum in all cases. Receiver-operating characteristic (ROC) curve analysis identified the highest peak at 96.3 cm3, with sensitivity of 0.643 and specificity of 0.864. Univariate analysis revealed dirty mass volume, acute disseminated intravascular coagulation (DIC) score, acute physiology and chronic health evaluation II (APACHE II) score, and sequential organ failure assessment (SOFA) score as prognostic markers for mortality (p<0.01). Multivariate analysis revealed dirty mass volume and APACHE II score as independent prognostic indicators for mortality. Mortality was stratified by dividing patients into four groups according to dirty mass volume and APACHE II score.ConclusionsThe combination of dirty mass volume and APACHE II score could stratify the postoperative mortality risk in patients with colorectal perforation. According to the risk stratification, surgeons might be able to decide the surgical procedures and intensity of postoperative management.

A case of congenital bronchial atresia: Usefulness of preoperative multi-detector row computed tomography (MDCT) for selection of surgical procedure

A case of congenital bronchial atresia: Usefulness of preoperative multi-detector row computed tomography (MDCT) for selection of surgical procedure

Effects of fluoride intake on cortical and trabecular bone microstructure at early adulthood using multi-row detector computed tomography (MDCT).

The aim of this study was to examine the effects of period-specific and cumulative fluoride (F) intake on bone at the levels of cortical and trabecular bone microstructural outcomes at early adulthood using emerging multi-row detector computed tomography (MDCT)-based novel techniques. Ultra-high resolution MDCT distal tibia scans were collected at age 19 visits under the Iowa Bone Development Study (IBDS), and cortical and trabecular bone microstructural outcomes were computed at the distal tibia using previously validated methods. CT scans of a tissue characterization phantom were used to calibrate CT numbers (Hounsfield units) into bone mineral density (mg/cc). Period-specific and cumulative F intakes from birth up to the age of 19years were assessed for IBDS participants through questionnaire, and their relationships with MDCT-derived bone microstructural outcomes were examined using bivariable and multivariable analyses, adjusting for height, weight, maturity offset (years since age of peak height velocity (PHV)), physical activity (questionnaire for adolescents (PAQ-A)), healthy eating index version 2010 (HEI-2010) scores, and calcium and protein intakes. MDCT distal tibia scans were acquired for 324 participants from among the total of 329 participants at age 19 visits. No motion artifacts were observed in any MDCT scans, and all images were successfully processed to measure cortical and trabecular bone microstructural outcomes. At early adulthood, males were observed to have stronger trabecular bone microstructural features, as well as thicker cortical bone (p<0.01), as compared to age-similar females; however, females were found to have less cortical bone porosity as compared to males. Among participants with available F intake estimates (75 to 91% of the 324 with MDCT scans, depending on the period-specific F intake measure), no statistically significant associations were detected between any period-specific or cumulative F intake and bone microstructural outcomes of the tibia at the p<0.01 level. Only for females, statistically suggestive associations (p<0.05) were found between recent F intake (from 14 to 19years) and trabecular mean plate width and trabecular thickness at the tibia. Those associations became somewhat weaker, but still statistically suggestive, for trabecular thickness in fully adjusted analysis with height, weight, PHV, calcium and protein intake, and HEI-2010 and PAQ-A scores as covariates. The findings show that the effects of lifelong or period-specific F intake from combined sources for adolescents typical to the United States Midwest region are not strongly associated with bone microstructural outcomes at age 19years. These findings are generally consistent with previously reported results of IBDS analyses, which further confirms that effects of lifelong or period-specific F intake on skeletons in early adulthood are absent or weak, even at the levels of cortical and trabecular bone microstructural details.

Detection of a peritumoral pseudocapsule in patients with renal cell carcinoma undergoing robot-assisted partial nephrectomy using enhanced MDCT

To investigate the detection of peritumoral pseudocapsule (PC) using multi-detector row computed tomography (MDCT) for tumors resected by robot-assisted laparoscopic partial nephrectomy (RAPN) for T1 renal cell carcinoma (RCC). Study participants included 206 patients with clinical T1 RCC who underwent RAPN between October 2017 and February 2018. Two radiologists who were blinded to the pathological findings evaluated the computed tomography (CT) images. Radiological diagnosis of a PC was defined by a combination of observations, including a low-attenuation rim between the tumor and renal cortex in the cortico-medullary phase and a high-attenuation rim at the edge of the tumor in the nephrogenic or excretory phase. A PC was detected on CT in 156/206 tumors (76%) and identified by pathology in 182/206 (88%) tumors including 153/166 (92%) clear cell RCC, 13/14 (93%) papillary RCC, and 7/16 (44%) chromophobe RCC. In the whole cohort, CT findings showed a sensitivity of 81.3% (148/182), specificity of 66.7% (16/24), and positive predictive value of 94.9% (148/156). When the data were stratified according to pathological subtypes, MDCT was observed to have a sensitivity of 86.9% (133/153) and specificity of 61.5% (8/13) in clear cell RCC, sensitivity of 38.5% (5/13) and specificity of 100% (1/1) in papillary RCC, and sensitivity of 44.4% (4/7) and specificity of 66.7% (6/9) in chromophobe RCC. A low or high-attenuation rim around the tumor in the cortico-medullary or nephrographic-to-excretory phase indicates a PC of RCC, though the accuracy is not satisfactory even with 64- or 320-detector MDCT.

Effect of image quality on myocardial extracellular volume quantification using cardiac computed tomography: a phantom study.

The image quality directly affects the accuracy of computed tomography (CT) extracellular volume (ECV) quantification. To investigate the effects of image quality and acquisition protocol on the accuracy of ECV quantification. One-volume scans were performed on a 320-row multidetector CT volume scanner using a multi-energy CT phantom. To simulate the blood pool and myocardium, solid rods representing blood and soft tissue were used in precontrast CT. Moreover, the solid rods including different iodine concentrations were used in postcontrast CT. The tube voltage was set at 120 kVp, and the tube current was changed from 750 mA (100% dose) to 190 mA (25% dose). All images underwent full- and half-scan reconstructions based on model-based iterative reconstruction. The ECV was calculated from the CT numbers between pre- and postcontrast. The mean ECV with full- and half-scan reconstructions at the central portion was 0.275 at 100% scan dose to 0.271 at 25% scan dose and 0.276 at 100% scan dose to 0.269 at 25% scan dose. Compared with that in the 100% scan dose, the variation in each ECV increased with decreasing radiation dose. The ECV at the center of the image along the z-axis had lower variation than that at outer portion of the images. On the reconstruction algorithm, there was no statistical difference in ECVs with full- and half-scan reconstructions. For stable ECV quantifications, excessive radiation dose reduction may be inappropriate, and it is better to consider the variations in ECV values depending on the slice location.

Multiphase multidetector-row computed tomographic and ultrasonographic findings in dogs with spontaneous liver lobe torsion

Liver lobe torsion (LLT) is an uncommon condition of unknown origin in dogs. Several reports describe the clinical features and outcome, but only few of them include the imaging characteristics of this disease.The aim of this descriptive case series was to describe the ultrasonographic (US) and multidetector-row computed tomographic (MDCT) features of LLT in a group of dogs.Five dogs were included in this single-center descriptive study, having both US, CT and surgical and histological confirmation of LLT available for review.Different US appearances have been found, both hypoechoic and hyperechoic liver lobes and heterogeneous mass-like lesions, with fluid and gas content. At three-phase MDCT examination, LLT appeared as fluid- and gas-filled lesions (consistent with abscess transformation), or as hypoattenuating hypovascular lobes. Two different vascular signs were also described: whirl sign or vascular interruption were seen in all cases, allowing a correct pre-surgical diagnosis in all the cases presented.Multiphase MDCT was a helpful imaging method for the correct pre-surgical diagnosis of LLT in dogs, and its use in the suspected cases is therefore advisable.

Comparison of cortico-medullary phase contrast-enhanced MDCT and T2-weighted MR imaging in the histological subtype differentiation of renal cell carcinoma: radiology-pathology correlation.

PurposeRenal cell carcinoma (RCC) subtype differentiation is of crucial importance in the management and prognosis of these patients. In this study, we investigated the usefulness of unenhanced and cortico-medullary phase contrast-enhanced multidetector-row computed tomography (MDCT) and T2-weighted fast spin-echo (FSE) magnetic resonance imaging (MRI) modalities in the discrimination of the 3 main subtype RCC patients in correlation with their histopathological findings.Material and methodsA total of 80 pathologically proven RCC patients who had undergone either partial or total nephrectomy were retrospectively investigated in this study. Their histological subtypes were 54 clear cell renal cell carcinoma (ccRCC), 15 papillary renal cell carcinoma (pRCC), and 11 chromophobe renal cell carcinoma (cRCC), based on pathological evaluation. There were 62 male (77.5%) and 18 female (22.5%) patients. Among the 54 ccRCC patients, 29 patients had both non-contrast and cortico-medullary phase CT, 1 had only non-contrast CT, 5 only had cortico-medullary phase CT, and 38 had MRI examination. In the pRCC group, 10 patients had both non-contrast and cortico-medullary phase CT, 1 had only non-contrast CT, 1 had only cortico-medullary phase CT, and 12 had MRI. Finally, in the remaining 11 cRCC patients, 9 had both non-contrast and cortico-medullary phase CT, and only 5 had MRI. We calculated both tumour attenuation values as HU (Hounsfield units) on unenhanced and cortico-medullary phase MDCT images and also tumour mean signal intensity values on FSE T2-weighted MRI images by using the region of interest (ROI) including normal renal cortex measurements. Besides quantitative evaluation, we also performed qualitative visual assessment of tumours on contrast-enhanced MDCT and FSE T2-weighted MRI.ResultsThere was no statistically significant difference among the attenuation values of the 3 tumour subtypes on pre-contrast CT images. ccRCC demonstrated a prominent degree of contrast enhancement compared to the chromophobe and papillary ones on cortico-medullary phase MDCT. We found no statistically significant difference between chromophobe and papillary subtypes, although chromophobe tumours showed slightly higher attenuation values compared to papillary ones. ccRCCs usually demonstrated a heterogenous contrast enhancement on cortico-medullary phase CT images, while the papillary subtype usually had a homogenous appearance on visual assessment. On FSE T2-weighted MR images, the signal intensity values of ccRCC patients were found to be significantly higher than both chromophobe and papillary subtypes. Although cRCC patients had a prominently lower T2 signal intensity than clear cell subtype, there was no statistically significant signal intensity difference between chromophobe and papillary subtypes. Regarding visual assessment, papillary subtype tumours showed a mostly homogenous appearance on T2-weighted images and a statistically significant difference was present. On the other hand, there was no significant difference of visual assessment of the clear cell and chromophobe subtypes.ConclusionsThe measurement of the attenuation values on cortico-medullary phase MDCT and the mean signal intensity values on FSE T2-weighted MRI can provide useful information in the differentiation of RCC main subtypes. Also, visual assessment of tumours on both modalities can contribute to this issue by providing additional imaging properties.

CT evaluation of bronchogenic carcinoma

HRCT delineation of lung parenchyma down to the level of the secondary pulmonary lobule is possible. Spiral CT introduced in the early 1990’s lead to an increase in utilization CT, a revolution that continued with advent of multi detector row CT (MDTC) scanners more recently. Helical technology permits multiple phases of scanning to be obtained often one contrast injection. In this study CT evaluation of 50 patients with either proven or strongly suspected bronchogenic carcicnoma based on chest radiographs, bronchoscopy, cytology of bronchial washings or pleural fluid, FNAC or clinical examination was done.Before commencing CT examination, all the preceding historical, clinical & laboratory data are recorded.Most of the bronchogenic carcinoma are heterogeneously enhancing (54.3%),with ill defined/ speculated margins (73.9%)and associated with necrosis in 43.47%of cases .calcification rarely found (13%).

Congenital absence of the azygos vein causing an aortic nipple: a case report

A 53-year-old male patient presented with chest pain and tightness for one hour. Frontal chest radiograph showed a tortuous aorta and a subtle aortic nipple at the left aspect of the aortic arch; the azygos vein shadow was not seen. Contrast-enhanced multi-detector row computed tomography (MDCT) showed absent azygos vein and prominent left superior intercostal vein communicating the accessory hemiazygos vein to the left brachiocephalic vein. Clinical improvement was noted. The patient was then discharged from the emergency department.

Arterial blood supply from accessary middle colic artery to the pancreas

Background: An accessory middle colic artery (AMCA) is an aberrant artery feeding the splenic flexure of the colon. Little is known about the branching pattern of the AMCA to the pancreas. We aimed to evaluate the branching pattern of the AMCA from the superior mesenteric artery (SMA) with special reference to the pancreatic artery using multidetector-row computed tomography (MDCT).

A comparative study of trabecular bone micro-structural measurements using different CT modalities

Osteoporosis, characterized by reduced bone mineral density and micro-architectural degeneration, significantly enhances fracture-risk. There are several viable methods for trabecular bone micro-imaging, which widely vary in terms of technology, reconstruction principle, spatial resolution, and acquisition time. We have performed an excised cadaveric bone specimen study to evaluate different computed tomography (CT)-imaging modalities for trabecular bone micro-structural analysis. Excised cadaveric bone specimens from the distal radius were scanned using micro-CT and four in vivo CT imaging modalities: high-resolution peripheral quantitative computed tomography (HR-pQCT), dental cone beam CT (CBCT), whole-body multi-row detector CT (MDCT), and extremity CBCT. A new algorithm was developed to optimize soft thresholding parameters for individual in vivo CT modalities for computing quantitative bone volume fraction maps. Finally, agreement of trabecular bone micro-structural measures, derived from different in vivo CT imaging, with reference measures from micro-CT imaging was examined. Observed values of most trabecular measures, including trabecular bone volume, network area, transverse and plate-rod micro-structure, thickness, and spacing, for in vivo CT modalities were higher than their micro-CT-based reference values. In general, HR-pQCT-based trabecular bone measures were closer to their reference values as compared to other in vivo CT modalities. Despite large differences in observed values of measures among modalities, high linear correlation (r ε [0.94 0.99]) was found between micro-CT and in vivo CT-derived measures of trabecular bone volume, transverse and plate micro-structural volume, and network area. All HR-pQCT-derived trabecular measures, except the erosion index, showed high correlation (r ε [0.91 0.99]). The plate-width measure showed a higher correlation (r ε [0.72 0.91]) among in vivo and micro-CT modalities than its counterpart binary plate-rod characterization-based measure erosion index (r ε [0.65 0.81]). Although a strong correlation was observed between micro-structural measures from in vivo and micro-CT imaging, large shifts in their values for in vivo modalities warrant proper scanner calibration prior to adopting in multi-site and longitudinal studies.

Impact of baseline feature tracking multi-detector row computed tomography-derived left ventricular global longitudinal strain on left ventricular functional recovery in TAVI patients

Abstract Background Advances in left ventricular (LV) analysis with dynamic multi-detector row computed tomography (MDCT) permit measurement of LV global longitudinal strain (GLS) and have shown their impact on risk stratification of patients with aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI). Purpose To evaluate the influence of baseline feature tracking (FT) MDCT- derived LV GLS on LV functional recovery in severe AS patients undergoing TAVI. Methods A total of 194 patients with severe AS (50% male, 80±7 years) with dynamic MDCT data allowing LV GLS measurement with a novel FT algorithm and having complete echocardiography evaluation at baseline, at 3–6 months and at 1 year follow-up were evaluated. FT MDCT-derived LV GLS was measured at baseline and the study population was divided according to a cut-off value of MDCT LV GLS −14% (≤−14% [more preserved LV systolic function] vs. &amp;gt;−14% [more impaired LV systolic function]). Results Transthoracic echocardiography (TTE)-derived Left ventricular ejection fraction (LVEF) increased over time in both groups: in patients with preserved and reduced MDCT LV GLS, and reached a higher value in patients with preserved MDCT LV GLS (52±7% at baseline, 55±7% at 3–6 months, 58±7% at 1 year follow-up vs. 43±10% at baseline, 49±10% at 3–6 months, 53±11% at 1 year follow-up; p=0.016) (Figure 1). TTE-derived LV GLS also showed greater improvement for patients with preserved MDCT LV GLS (−17±3% at baseline, −18±3% at 3–6 months, −20±3% at 1 year follow-up vs. −12±3% at baseline, −15±3% at 3–6 months, −16±3% at 1 year follow-up; p=0.027) (Figure 1). Conclusions In severe AS patients treated with TAVI, LV function improves significantly at 3–6 and at 12 months' follow-up and shows superior recovery in patients with more preserved baseline MDCT LV GLS, suggesting that MDCT-derived LV GLS has an important impact on LV functional recovery after TAVI. Funding Acknowledgement Type of funding source: None

Cardiac damage grading in patients with aortic stenosis using multi-detector computed tomography and the impact on prognosis after transcatheter aortic valve intervention

Abstract Introduction A staging of severe aortic stenosis (AS) based on additional extra-valvular cardiac damage has been associated with prognosis after transcatheter aortic valve implantation (TAVI). Multi-detector row computed tomography (MDCT) has a central role in the evaluation of AS patients undergoing TAVI and can detect extra-valvular cardiac damage. Purpose To evaluate the prognostic implications of an MDCT staging system of severe AS in patients undergoing TAVI. Methods Patients who underwent full-beat MDCT prior to TAVI were included. Patients with intra-cardiac devices, prior valvular surgery, and insufficient image quality were excluded. The extent of cardiac damage was assessed by MDCT and classified into following 5 groups; stage 0 (no cardiac damage), stage 1 (left ventricular damage), stage 2 (left atrium and mitral valve damage), stage 3 (right atrial damage), stage 4 (right ventricular damage). The primary end-point was all-cause mortality. Results A total of 405 patients (80±7 years, 52% men) were stratified according to the MDCT staging system: 27 (7%) were in stage 0, 96 (24%) in stage 1, 152 (38%) in stage 2, 78 (19%) in stage 3, and 52 (13%) in stage 4 (left panel). During follow-up (median 3.7 years, IQR: 1.7–5.5 years), 150 (37%) died (right panel). On multivariable analysis, cardiac damage stage, presence of chronic obstructive pulmonary disease, NYHA ≥3, eGFR, and transapical approach were independently associated with all-cause mortality. When evaluating each stage, stage 3 (HR: 4.725, P=0.033) and stage 4 (HR 5.678, P=0.018) were independently associated with worse outcomes as compared to the other stages. Conclusion MDCT-based staging system of severe AS identifies the patients who are at higher risk of death after TAVI. MDCT staging and the mortality Funding Acknowledgement Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): ESC research grant

Delayed hyperenhancement obtained by non-contrast computed tomography following coronary angiography in patients of extracorporeal cardiopulmonary resuscitation

Abstract Background/Introduction Extracorporeal cardiopulmonary resuscitation (ECPR) has been reported to improve survival and neurologic outcome as compared to conventional CPR in refractory cardiac arrest. Although prognostic factors of these patients have been reported, predicting of outcome is difficult in real world. Recently, early evaluation of myocardial viability in acute myocardial infarction by non-contrast computed tomography (CT) post coronary angiography (CAG) has been reported. And myocardial contrast delayed enhancement obtained by this method related to higher risk of cardiac events. However, few studies have reported delayed enhancement on left ventricular wall findings in non-contrast CT after CAG in terms of patients performed ECPR. Purpose To investigate the impact of delayed hyperenhancement obtained by non-contrast CT following CAG in patients performed ECPR. Methods We investigated 79 patients treated by ECPR for refractory cardiac arrest regardless of whether in-hospital or out-hospital in our institute from Apr 2009 to Feb 2018. Thirty-two in these patients received non-contrast CT following CAG with ECPR were enrolled. All ECPR cases underwent VA-ECMO in the catheter laboratory using percutaneous procedure while maintaining conventional CPR. Non-ECG-gated and non-contrast CT was performed using a 64-row multidetector CT scanner. Results Survival rate was 18.8% in this cohort. There was no significant difference between survive and in-hospital death group in terms of patient characteristics, clinical time courses, initial blood samples and procedure characteristics. Only delayed hyperenhancement showed significant difference between 2 groups (p=0.04). All delayed hyperenhancements were detected in only in-hospital death group. Delayed hyperenhancement was detected in 12 cases (37.5%). Initial shockable rhythm was less common in cases with delayed hyperenhancement. Cardiac death tended to be more frequent in patients with delayed hyperenhancement. The major causes of death were bleeding (41.7%) and heart failure (33%). Conclusion(s) Delayed hyperenhancement in patients treated ECPR was strong predictor of in-hospital death. Image of delayed hyperenhancement Funding Acknowledgement Type of funding source: None

Artificial intelligence in image reconstruction: The change is here.

Innovations in CT have been impressive among imaging and medical technologies in both the hardware and software domain. The range and speed of CT scanning improved from the introduction of multidetector-row CT scanners with wide-array detectors and faster gantry rotation speeds. To tackle concerns over rising radiation doses from its increasing use and to improve image quality, CT reconstruction techniques evolved from filtered back projection to commercial release of iterative reconstruction techniques, and recently, of deep learning (DL)-based image reconstruction. These newer reconstruction techniques enable improved or retained image quality versus filtered back projection at lower radiation doses. DL can aid in image reconstruction with training data without total reliance on the physical model of the imaging process, unique artifacts of PCD-CT due to charge sharing, K-escape, fluorescence x-ray emission, and pulse pileups can be handled in the data-driven fashion. With sufficiently reconstructed images, a well-designed network can be trained to upgrade image quality over a practical/clinical threshold or define new/killer applications. Besides, the much smaller detector pixel for PCD-CT can lead to huge computational costs with traditional model-based iterative reconstruction methods whereas deep networks can be much faster with training and validation. In this review, we present techniques, applications, uses, and limitations of deep learning-based image reconstruction methods in CT.