A Comparison of Retrospective ECG-Gated CT and Surgical or Angiographical Findings in Acute Aortic Syndrome.

The best cardiac phases in retrospective ECG-gated CT for detecting an intimal tear (IT) in aortic dissection (AD) and an ulcer-like projection (ULP) in an intramural hematoma (IMH) have not been established. This study aimed to compare the detection accuracy of diastolic-phase and systolic-phase ECG-gated CT for IT in AD and ULP in IMH, with subsequent surgical or angiographical confirmation as the reference standard.In total, 81 patients (67.6 ± 11.8 years; 41 men) who underwent emergency ECG-gated CT and subsequent open surgery or thoracic endovascular aortic repair for AD (n = 52) or IMH (n = 29) were included. The accuracies of detecting IT and ULP were compared among only diastolic-phase, only systolic-phase, and both diastolic-phase and systolic-phase methods of retrospective ECG-gated CT; surgical or angiographical findings were used as the reference standard. The detection accuracy for IT and ULP using only diastolic-phase, only systolic-phase, and both diastolic-phase and systolic-phase methods of ECG-gated CT was 93% [95% CI: 87-97], 94% [95% CI: 88-97], and 95% [95% CI: 90-97], respectively. There were no significant differences in detection accuracy among the 3 acquisition methods (P = 0.55). Similarly, there were no significant differences in the accuracy of detecting IT in AD (P = 0.55) and ULP in IMH (P > 0.99) among only diastolic-phase, only systolic-phase, and both diastolic- and systolic-phase ECG-gated CT.Retrospective ECG-gated CT for detecting IT in AD and ULP in IMH yields highly accurate findings. There were no significant differences seen among only diastolic-phase, only systolic-phase, and both diastolic-phase and systolic-phase ECG-gated CT.

Crystal structure of poly[(aceto-nitrile-κN)(µ3-7-{[bis-(pyridin-2-ylmeth-yl)amino]-meth-yl}-8-hy-droxy-quinoline-5-sulfonato-κ4N,O:O':O'')sodium].

In the title compound, [Na(C22H19N4O4S)(CH3CN)]n, the NaI atom adopts a distorted square-pyramidal coordination geometry, formed by one N and one O atom of the qunolinol moiety in the ligand, two O atoms of sulfonate moieties of two adjacent ligands and the N atom of the coordinated aceto-nitrile solvent. The NaI atom is located well above the mean basal plane of the square-based pyramid. The apical position is occupied by a sulfonate O atom of a neighboring ligand. Three N atoms of the bis-(pyridin-2-ylmeth-yl)amine moiety in the ligand are not coordinated by the sodium atom. The mol-ecule forms an intra-molecular bifurcated O-H⋯[N(tertiary amine),N(pyridine)] hydrogen bond, generating S(6) and S(5) rings. In the crystal, four mol-ecules are linked by four Na-O(sulfonato) bridged coordination bonds, forming a supra-molecular centrosymmetric tetra-mer unit comprising an eight-membered ring, and generating a two-dimensional network sheet. The mol-ecules of different sheets form inter-molecular C-H⋯O hydrogen bonds, and thereby a three-dimensional network structure.

Evaluating the Optimal Oil Concentrations in the Startup Performance of a Membrane Bioreactor Treating Oily Noodle-soup Wastewater.

The discharge of high-strength oily wastewater adversely affects the environment; therefore, the treatment of wastewater containing fats, oils, and grease from the food industry is of importance. In this study, we used a membrane bioreactor (MBR) to treat Ramen noodle-soup wastewater, and we evaluated the optimal oil concentration in the wastewater for the startup of the MBR treatment in winter and summer. The MBR system had a sufficient startup in both seasons when fed with a 20-fold dilution of the original oily wastewater, containing approximately 950 to 1,200 mg/L oil and approximately 3,000 to 4,400 mg/L biological oxygen demand (BOD; BOD-SS load of 0.1 to 0.2 kg/kg/d). The reactor performance in winter were relatively stable during the operation. While, activated sludge microbes in summer were not highly active with a 40-fold dilution of wastewater, because of the decreased mixed liquor suspended solid concentration during the operation period. Population shifts in the sludge microbiome with increasing oil concentrations were analyzed using high-throughput sequencing, and the relative abundance of operational taxonomic units belonging to the phylum Bacteroidetes were highest in both winter and summer when fed with 20-fold dilution of the wastewater. In particular, the family Chitinophagaceae was dominant, with relative abundances of 13.5% in winter and 5.1% in summer, suggesting that this family may play important roles in the startup of a MBR treating the wastewater.

Outcomes of embolization procedures for type II endoleaks following endovascular abdominal aortic repair.

OBJECTIVE: The objective of this study was to investigate the mid-term outcomes of embolization procedures for type II endoleak after endovascular abdominal aortic repair, and clarify the risk factors for aneurysm enlargement after embolization procedures. METHODS: This was a retrospective multicenter registry study enrolling patients who underwent embolization procedures for type II endoleaks after EVAR from January 2012 to December 2018 at 19 Japanese centers. The primary end point was the rate of freedom from aneurysm enlargement, more than 5 mm in the aortic maximum diameter, after an embolization procedure. Demographic, procedural, follow-up, and laboratory data were collected. Continuous variables were summarized descriptively, and Kaplan-Meier analyses and a Cox regression model were used for statistical analyses. RESULTS: A total of 315 patients (248 men and 67 women) were enrolled. The average duration from the initial embolization procedure to the last follow-up was 31.6 ± 24.6 months. The rates of freedom from aneurysm enlargement at 3 and 5 years were 55.4 ± 3.8% and 37.0 ± 5.2%, respectively. A multivariate analysis revealed that a larger aortic diameter at the initial embolization procedure and the presence of a Moyamoya endoleak, defined as heterogeneous contrast opacity with an indistinct faint border, were associated with aneurysm enlargement after embolization management. CONCLUSIONS: The embolization procedures were generally ineffective in preventing further expansion of abdominal aortic aneurysms in patients with type II endoleaks after EVAR, especially in patients with a large abdominal aortic aneurysm and/or a presence of a Moyamoya endoleak.

Aortic Elongation in Bicuspid Aortic Valve with Aortic Stenosis Assessed by Thin-Slice Electrocardiogram-Gated Computed Tomography.

Bicuspid aortic valve (BAV) patients with aortic stenosis (AS) are known to develop dilatation of the ascending aorta at a younger age, but the morphology of the aorta in these patients is yet to be investigated. Thus, in this study, we aim to evaluate the aortic morphology of BAV patients with severe AS using thin-slice electrocardiogram (ECG) -gated computed tomography (CT) and identify the possible contributing effect of age.In this retrospective study, 122 BAV and 154 tricuspid aortic valve (TAV) patients who received aortic valve replacement for severe AS were assessed by thin-slice ECG-gated CT and three-dimensional reconstruction. The morphology of the ascending aorta was also evaluated among BAV patients aged < 70 (n = 72) and ≥ 70 (n = 50) years old. As per our findings, BAV patients with severe AS had significantly greater diameter (P < 0.01), elongation (P < 0.01), and tortuosity (P = 0.03) of the ascending aorta; minimum aortic arch angle (P < 0.01); and significantly lower calcified plaque (P < 0.01) compared with those of TAV patients even after adjusting for background. Multiple regression analysis showed that standardized partial regression coefficients (ß) of dilatation (0.5) and elongation (0.35) were higher among other measurements of aortic morphology for BAV patients. BAV patients with severe AS aged ≥ 70 years had significantly greater diameter (42.0 [37.2-46.1] mm versus 40.4 [35.2-44.2] mm, P = 0.049) and elongation (133.8 [123.5-147.3] mm versus 127.0 [111.0-140.0] mm, P = 0.01) of the ascending aorta than those aged < 70 years.BAV patients with severe AS were determined to have greater dilatation and elongation of the ascending aorta. Moreover, BAV patients older than 70 years had greater diameter and elongation of the ascending aorta.

CT imaging with ultra-high-resolution: Opportunities for cardiovascular imaging in clinical practice.

Cardiovascular computed tomography (CT) angiography has become an established alternative to invasive catheter angiography. However, imaging artifacts due to partial volume effects with current systems hinder accurate evaluation of calcified or stented segments. Increased spatial resolution may allow to overcome these barriers to precise delineation of vascular disease. Recent developments in CT hardware and reconstruction have enabled CT angiography with ultra-high spatial resolution (UHRCT). In this review we aim to describe the methods to achieve greater spatial resolution in CT that are either in clinical or preclinical stage. In addition, we provide an overview of the available clinical evidence including diagnostic accuracy studies supporting improved vascular assessment with this technology. The benefits that can be gleaned from the initial experiences with UHRCT are promising. Using UHRCT, more patients may receive non-invasive characterization of coronary atherosclerosis by overcoming the limitations of current CT spatial resolution in visualizing and quantifying calcified, stented or small diameter segments. UHRCT may potentially impact existing management pathways as well as contribute to better understanding of the underlying pathophysiology of both macro- and microvascular disease.

Clinical Diagnostic Imaging Study of Osteoradionecrosis of the Jaw: A Retrospective Study.

Radiation therapy (RT) plays a significant role in the management of head and neck malignancies. This study aimed to review the clinical symptoms and various imaging findings of osteoradionecrosis (ORN) and provide a clinical perspective on the development of ORN. The retrospective cohort was composed of 57 sites in 54 patients who had a history of RT and suspected ORN and 48 sites in 45 patients who were confirmed to have ORN. Image analyses included computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET)/CT, bone scintigraphy, and single-photon emission CT (SPECT). The irradiated tissue was damaged by RT, and the extent of damage was correlated with clinical symptoms. The bone marrow showed sclerotic changes and the devitalized bone showed bone resorption after invasive stimulation. Chronic trismus and pathological fracture are considered severe conditions, typically occurring in the last stage of ORN. Furthermore, neurological symptoms were an important sign of tumor recurrence, since diagnostic imaging was difficult. The possible treatment options vary depending on the stage of ORN. We speculate that bone sclerosis reactions and bone resorption are sequential reactions that seem to be protective measures of the bone to radiation injury.

Additive Value of CT to Age, Aortic Diameter, and Echocardiography in Diagnosis and Classification of Bicuspid Aortic Valve in Patients with Severe Aortic Stenosis.

PURPOSE: To develop and validate a CT diagnostic algorithm for bicuspid aortic valve (BAV) classification. MATERIALS AND METHODS: This retrospective study included 212 consecutive patients with severe aortic stenosis who underwent CT followed by aortic valve replacement (mean age, 71 years [range, 27-93 years]; 125 women; 37% with a BAV) from 2012 to 2017. BAV diagnosis and BAV category were determined by using the CT diagnostic algorithm developed and were compared with those attained through surgical diagnosis. Reproducibility and agreement were assessed using the Cohen kappa (κ) coefficient. The value of adding CT to age, aortic diameter index, and transthoracic echocardiography (TTE) was evaluated by using the area under the receiver operating characteristic curve (AUC), net reclassification improvement (NRI), and decision-curve analysis. RESULTS: Intra- and interobserver reproducibility were good or excellent for all CT diagnoses (κ ≥ 0.6 for all). Agreement between CT and surgical diagnoses was excellent (κ = 0.90) for BAV detection and good (κ = 0.69) for BAV categorization. Sixteen percent (five of 31) of patients with functional BAV diagnosed by using CT received a diagnosis of congenital BAV at surgery. The addition of CT to age, aortic diameter, and TTE showed a higher AUC (with CT, 0.97 [95% CI: 0.91, 0.99] vs without CT, 0.91 [95% CI: 0.85, 0.95]; P = .003) and NRI (1.79 [95% CI: 1.65, 1.92], P < .001) and a higher net benefit among all BAV probabilities. CONCLUSION: CT diagnosis was consistent with surgical diagnosis and had an additive value over traditional diagnostic methods; however, there was a risk of overlooking congenital BAV in patients with functional BAV diagnosed by using CT.Supplemental material is available for this article.© RSNA, 2021.

Optimal Phosphate Control Related to Coronary Artery Calcification in Dialysis Patients.

BACKGROUND: In patients on maintenance dialysis, cardiovascular mortality risk is remarkably high, which can be partly explained by severe coronary artery calcification (CAC). Hyperphosphatemia has been reported to be associated with the severity of CAC. However, the optimal phosphate range in patients on dialysis remains unknown. This study was planned to compare the effects on CAC progression of two types of noncalcium-based phosphate binders and of two different phosphate target ranges. METHODS: We conducted a randomized, open-label, multicenter, interventional trial with a two by two factorial design. A total of 160 adults on dialysis were enrolled and randomized to the sucroferric oxyhydroxide or lanthanum carbonate group, with the aim of reducing serum phosphate to two target levels (3.5-4.5 mg/dl in the strict group and 5.0-6.0 mg/dl in the standard group). The primary end point was percentage change in CAC scores during the 12-month treatment. RESULTS: The full analysis set included 115 patients. We observed no significant difference in percentage change in CAC scores between the lanthanum carbonate group and the sucroferric oxyhydroxide group. On the other hand, percentage change in CAC scores in the strict group (median of 8.52; interquartile range, -1.0-23.9) was significantly lower than that in the standard group (median of 21.8; interquartile range, 10.0-36.1; P=0.006). This effect was pronounced in older (aged 65-74 years) versus younger (aged 20-64 years) participants (P value for interaction =0.003). We observed a similar finding for the absolute change in CAC scores. CONCLUSIONS: Further study with a larger sample size is needed, but strict phosphate control shows promise for delaying progression of CAC in patients undergoing maintenance hemodialysis. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: Evaluate the New Phosphate Iron-Based Binder Sucroferric Oxyhydroxide in Dialysis Patients with the Goal of Advancing the Practice of EBM (EPISODE), jRCTs051180048.

Salt Mediated Modulation of Autolysis of Thermolysin-Like Proteinase, Salilysin, Isolated from a Moderate Halophile, Chromohalobacter salexigens DSM3043.

Halophilic salilysin is first synthesized as a pro-form, which has been shown autolysis activity to process pro-region (55 amino acids long) three times to form intermediate 1 (I1), intermediate 2 (I2) and final mature (M) salilysin. The autolysis of I1- to M-form salilysin in vitro was significantly accelerated with increasing NaCl concentration up to 4 M. Strong salting-out salts, (NH4)2SO4, Na2SO4 and MgSO4, were more effective, suggesting that autolysis is enhanced by inter-molecular association or structure compaction or both. However, MgCl2, a salting-in salt, was also effective, suggesting that other mechanisms, such as charge shielding and ionic binding to this halophilic protein, operated. Autolytic cleavage at site 3 resulted in mixed formation of correctly and incorrectly processed mature forms in the absence of salt, indicating that salt affected the accuracy of autolytic cleavage reaction. Far UV circular dichroism (CD) measurements indicated that E167A pro-salilysin showed an identical CD spectrum to the wild-type mature salilysin, suggesting pro-form has a proper fold for proteolytic activity. Thermal scanning indicated that E167A pro-salilysin was more heat-stable by ~ 10 °C than mature form. The CD spectra, thermal stability and modeling structure of salilysin clearly suggested that pro-salilysin is folded to the same structure as native form and is functional for autolysis.

Successful Ascending to Descending Aortic Bypass and Endovascular Embolisation of a Late Pseudoaneurysm Following Patch Aortoplasty for Coarctation of the Aorta.

INTRODUCTION: A late aortic aneurysm at the site of previous open surgery for coarctation of the aorta (CoA) is a life threatening complication. Several strategies have been reported, however, these strategies have issues. This is the report of a case involving successful ascending to descending aortic bypass concomitant with endovascular embolisation for a pseudoaneurysm. REPORT: The patient was a 23 year old man with a history of patch aortoplasty for coarctation of the aorta (CoA) via a left thoracotomy and patch closure of a ventricular septal defect. Enhanced computed tomography (CT) angiography performed in 2014 revealed a pseudoaneurysm at the site of the previous patch aortoplasty. CT also revealed a hypoplastic and severely kinked aortic arch that made it difficult to perform conventional thoracic endovascular aortic repair for this aneurysm. Therefore in order to prevent rupture, a combination of ascending to descending aortic bypass and endovascular embolisation using Amplatzer vascular plugs and coils was employed. Transection of the aortic arch and transposition of the left subclavian artery were performed to prevent antegrade flow into the aneurysm. DISCUSSION: The aneurysm was successfully excluded without complications. CT performed three years after the operation showed that the pseudoaneurysm had shrunk completely. Extra-anatomic bypass concomitant with endovascular embolisation for a late coarctation patched site aneurysm might be an alternative strategy that should be carefully considered in specific cases.

Salt-enhanced processing, proteolytic activity and stability of halophilic thermolysin-like proteinase, salilysin, isolated from a moderate halophile, Chromohalobacter salexigens DSM3043.

Moderately halophilic bacterium, Chromohalobacter salexigens DSM3043, has a gene Csal_2537 encoding thermolysin-like M4 proteinase. This gene was cloned to pET expression vectors, resulting in high expression of recombinant proteinase, named as salilysin (salinity-dependent thermolysin-like proteinase), in Escherichia coli cytoplasm. This gene encodes precursor form of salilysin containing 348 amino acid residues (Pro-salilysin) consisting of 55 amino acids pro-sequence and following mature proteinase. Pro-sequence was cleaved three times to form intermediate 1, intermediate 2 and final mature salilysin. The processing rate was greatly accelerated in a salt concentration-dependent manner. Purified inactive mutant Pro-E167A-salilysin was correctly processed by purified mature salilysin, indicating that autolysis and inter-molecular processing occurred in its maturation processes. Proteolytic activity of mature salilysin against both peptide and protein substrates was also enhanced along with the addition of higher concentration of salt, 0-3.2 M NaCl, consistent with its halophilic origin. Mature salilysin was stabilized by ~8 °C in the presence of 1 M NaCl by thermal scanning using circular dichroism. One of the precursor form, intermediate 1, showed ~20 °C higher denaturation temperature than mature form, suggesting rigid and stable structure of this precursor form.

Updates on Computed Tomography Imaging in Aortic Aneurysms and Dissection.

Computed tomography (CT) is a primary imaging modality for the diagnosis of aortic diseases, because of its minimal invasiveness and agility. Prompt and accurate diagnosis is crucial especially for acute aortic diseases, and the guidelines for acute aortic dissection recommend the use of CT for initial diagnosis. For the follow-up observation of longstanding aortic diseases, the strategy of imaging management by CT must be different from that for emergency and acute phases. In this review, we document the differences in characteristics and clinical course between aortic aneurysm and aortic dissection and explain the use of recent CT techniques in diagnosing short- and longstanding aortic diseases.

Diagnostic accuracy of cardiac magnetic resonance imaging for cardiac sarcoidosis in complete heart block patients implanted with magnetic resonance-conditional pacemaker.

BACKGROUND: Cardiac magnetic resonance (CMR) imaging has become the principal noninvasive imaging modality for the diagnosis of cardiac sarcoidosis (CS) patients. This study aimed to determine the diagnostic performance of CMR imaging for CS in new-onset complete heart block (CHB) patients implanted with magnetic resonance-conditional pacemaker (MRCP). METHODS: Fifty CHB patients implanted with MRCP were enrolled in this study. Clinical CS was diagnosed if there was a histological diagnosis of extra-cardiac sarcoidosis in patients with CHB based on the consensus statement; clinical CS was the reference standard. The diagnostic performance of CMR sequences, including cine magnetic resonance imaging (MRI), increased T2-weighted signal (T2WS), and late gadolinium enhancement (LGE), for clinical CS was investigated. We also compared the diagnostic performance of CMR sequences between the entire left ventricle (LV) and the basal septum, which involves the electrical pathway of atrioventricular conduction. RESULTS: In total, 8 of the 50 patients with CHB were confirmed to have extra-cardiac sarcoidosis and were diagnosed with clinical CS. The accuracy, sensitivity, and specificity of LGE in the basal septum and entire LV were 94%, 100%, and 93% and 80% (p = 0.023), 100% (p = 1.00), and 76% (p = 0.023), respectively. The accuracy, sensitivity, and specificity of increased T2WS and cine MRI in the basal septum were 94%, 75%, and 98% and 90%, 38%, and 100%, respectively. There was no statistical difference between the entire LV and the basal septum for the diagnostic performance of increased T2WS and cine MRI. CONCLUSIONS: CMR can be a diagnostic tool for evaluating clinical CS in patients with CHB implanted with MRCP. LGE in the basal septum might provide the overall best diagnostic performance for clinical CS with CHB.

Recent Update on Peripheral Arterial Endovascular Therapy for Peripheral Arterial Occlusive Disease.

Endovascular treatment is effective for symptomatic peripheral arterial disease (PAD). Following recent device improvements, favorable long-term outcomes have been achieved in iliac arteries as well as small arteries such as the femoral and popliteal arteries. This paper outlines the history and recent advances in endovascular treatment of peripheral vascular diseases as well as the characteristics and usage of devices. The history and the advances in endovascular treatment of peripheral vascular disease have been parallel, with the development of devices such as catheters and stents. Accordingly, endovascular treatment is now recommended in guidelines as the first-line for PAD.

Management of Renal Arteries in Conjunction with Thoracic Endovascular Aortic Repair for Complicated Stanford Type B Aortic Dissection: The Japanese Multicenter Study (J-Predictive Study).

Background Management of abdominal branches associated with Stanford type B aortic dissection is controversial without definite criteria for therapy after thoracic endovascular aortic repair (TEVAR). This is in part due to lack of data on natural history related to branch vessels and their relationship with the dissection flap, true lumen, and false lumen. Purpose To investigate the natural history of abdominal branches after TEVAR for type B aortic dissection and the relationship between renal artery anatomy and renal volume as a surrogate measure of perfusion. Materials and Methods This study included patients who underwent TEVAR for complicated type B dissection from January 2012 to March 2017 at 20 centers. Abdominal aortic branches were classified with following features: patency, branch vessel origin, and presence of extension of the aortic dissection into a branch (pattern 1, supplied by the true lumen without branch dissection; pattern 2, supplied by the true lumen with branch dissection, etc). The branch artery patterns before TEVAR were compared with those of the last follow-up CT (mean interval, 19.7 months) for spontaneous healing. Patients with one kidney supplied by pattern 1 and the other kidney by a different pattern were identified, and kidney volumes over the course were compared by using a simple linear regression model. Results Two hundred nine patients (mean age ± standard deviation, 66 years ± 13; 165 men and 44 women; median follow-up, 18 months) were included. Four hundred fifty-nine abdominal branches at the last follow-up were evaluable. Spontaneous healing of the dissected branch occurred in 63% (64 of 102) of pattern 2 branches. Regarding the other patterns, 6.5% (six of 93) of branches achieved spontaneous healing. In 79 patients, renal volumes decreased in kidneys with pattern 2 branches with more than 50% stenosis and branches supplied by the aortic false lumen (patterns 3 and 4) compared with contralateral kidneys supplied by pattern 1 (pattern 2 vs pattern 1: -16% ± 16 vs 0.10% ± 11, P = .002; patterns 3 and 4 vs pattern 1: -13% ± 14 vs 8.5% ± 14, P = .004). Conclusion Spontaneous healing occurs more frequently in dissected branches arising from the true lumen than in other branch patterns. Renal artery branches supplied by the aortic false lumen or a persistently dissected artery with greater than 50% stenosis are associated with significantly greater kidney volume loss. © RSNA, 2019 Online supplemental material is available for this article.

Feasibility of thin-slice abdominal CT in overweight patients using a vendor neutral image-based denoising algorithm: Assessment of image noise, contrast, and quality.

The purpose of this study was to investigate whether the novel image-based noise reduction software (NRS) improves image quality, and to assess the feasibility of using this software in combination with hybrid iterative reconstruction (IR) in image quality on thin-slice abdominal CT. In this retrospective study, 54 patients who underwent dynamic liver CT between April and July 2017 and had a body mass index higher than 25 kg/m2 were included. Three image sets of each patient were reconstructed as follows: hybrid IR images with 1-mm slice thickness (group A), hybrid IR images with 5-mm slice thickness (group B), and hybrid IR images with 1-mm slice thickness denoised using NRS (group C). The mean image noise and contrast-to-noise ratio relative to the muscle of the aorta and liver were assessed. Subjective image quality was evaluated by two radiologists for sharpness, noise, contrast, and overall quality using 5-point scales. The mean image noise was significantly lower in group C than in group A (p < 0.01), but no significant difference was observed between groups B and C. The contrast-to-noise ratio was significantly higher in group C than in group A (p < 0.01 and p = 0.01, respectively). Subjective image quality was also significantly higher in group C than in group A (p < 0.01), in terms of noise and overall quality, but not in terms of sharpness and contrast (p = 0.65 and 0.07, respectively). The contrast of images in group C was greater than that in group A, but this difference was not significant. Compared with hybrid IR alone, the novel NRS combined with a hybrid IR could result in significant noise reduction without sacrificing image quality on CT. This combined approach will likely be particularly useful for thin-slice abdominal CT examinations of overweight patients.

Chronic contained rupture of abdominal aortic aneurism complicated with aortic occlusion: a case report.

BACKGROUND: Chronic contained rupture is a subtype of an abdominal aortic aneurysm rupture. Its diagnosis is sometimes difficult due to lack of typical symptoms. We would like to report the challenge of diagnosing chronic contained rupture of abdominal aortic aneurysm with a retroperitoneal tumor. CASE PRESENTATION: A 60-year-old man reported perceived lower abdominal pain 7 months earlier that spontaneously remitted. A contrast-enhanced computed tomography (CT) indicated an abdominal aortic aneurysm and a mass lesion surrounding the abdominal aorta and iliac arteries. Fluorine-18-fluorodeoxyglucose positron emission tomography (FDG-PET) showed an increased accumulation of FDG in the margin of the lesion, indicating a retroperitoneal tumor. A CT-guided biopsy revealed only retroperitoneal fibrous tissue with chronic inflammation. We were thus unable to reach a definitive diagnosis. At 1 month after the initial examination, intermittent claudication was newly observed. A follow-up contrast-enhanced CT scan revealed abdominal aortic occlusion. Mass resection and bypass surgery were performed for diagnosis and treatment. Intraoperative and pathological findings led to the diagnosis of chronic contained rupture of an abdominal aortic aneurysm. The patient was discharged 19 days after surgery. CONCLUSION: The mass peripheral to the abdominal aorta should be considered the possibility not only of tumor but also of chronic contained rupture of an abdominal aortic aneurysm.

Antegrade thoracic endovascular aortic repair via the left axillary artery in a patient with aortoiliac occlusive disease (Leriche syndrome).

We present the case of a 77-year-old man with a saccular descending thoracic aortic aneurysm who underwent successful antegrade thoracic endovascular aortic repair (TEVAR) via the left axillary artery. The patient had a history of axillo-bifemoral bypass grafting due to aortoiliac occlusive disease (Leriche syndrome), which precluded normal retrograde TEVAR. Upon successful procedure completion, no endoleak was noted on postoperative computed tomography. The patient was discharged from the hospital without any complications. The left axillary artery is useful as an alternative access site in cases wherein conventional retrograde TEVAR is not feasible.