Assessment of Image Quality for Selective Intracoronary Contrast-Injected CT Angiography in a Hybrid Angio-CT System: A Feasibility Study in Swine

Purpose@#To compare image quality in selective intracoronary contrast-injected computed tomography angiography (SelectiveCTA) with that in conventional intravenous contrast-injected CTA (IV-CTA). @*Materials and Methods@#Six pigs (35 to 40 kg) underwent both IV-CTA using an intravenous injection (60 mL) and Selective-CTA using an intracoronary injection (20 mL) through a guide-wire during/after percutaneous coronary intervention. Images of the common coronary artery were acquired. Scans were performed using a combined machine comprising an invasive coronary angiography suite and a 320-channel multi-slice CT scanner. Quantitative image quality parameters of CT attenuation, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), mean lumen diameter (MLD), and mean lumen area (MLA) were measured and compared. Qualitative analysis was performed using intraclass correlation coefficient (ICC), which was calculated for analysis of interobserver agreement. @*Results@#Quantitative image quality, determined by assessing the uniformity of CT attenuation (399.06 vs. 330.21, p<0.001), image noise (24.93 vs. 18.43, p<0.001), SNR (16.43 vs. 18.52, p=0.005), and CNR (11.56 vs. 13.46, p=0.002), differed significantly between IV-CTA and Selective-CTA. MLD and MLA showed no significant difference overall (2.38 vs. 2.44, p=0.068, 4.72 vs. 4.95, p=0.078).The density of contrast agent was significantly lower for selective-CTA (13.13 mg/mL) than for IV-CTA (400 mg/mL). Agreement between observers was acceptable (ICC=0.79±0.08). @*Conclusion@#Our feasibility study in swine showed that compared to IV-CTA, Selective-CTA provides better image quality and requires less iodine contrast medium.

Diagnostic Accuracy of a Novel On-site Virtual Fractional Flow Reserve Parallel Computing System

Predictors of Severe or Moderate Coronary Artery Disease in Asymptomatic Individuals with Extremely Low Coronary Calcium Scores

PURPOSE: To evaluate predictors of severe or moderate coronary artery disease (CAD) in individuals with zero or very low (<10) coronary artery calcium (CAC) scores. MATERIALS AND METHODS: The 1175 asymptomatic persons with zero or very low (<10) CAC scores were analyzed for CAD stenosis using coronary computed tomography angiography. Moderate and severe CADs were defined as having more than 50% and more than 70% stenosis in any of the major coronary arteries, respectively. Age, gender, body mass index, hypertension, type II diabetes, dyslipidemia, lipid profile, creatinine, and smoking status were evaluated as predictors for moderate and severe CAD. RESULTS: In the study population, moderate and severe CADs were found in 7.5% and 3.3%, respectively. Among evaluated risk factors, age [odds ratio (OR) 1.04, 95% confidence interval (CI) 1.02−1.07, p<0.001], current smoking status (OR 3.12, 95% CI 1.82−5.34, p<0.001), and CAC 1−9 (OR 1.80, 95% CI 1.08−3.00, p=0.024) were significantly associated with moderate CAD. Meanwhile, age (OR 1.05, 95% CI 1.02−1.08, p=0.003), low high density lipoprotein (HDL) (OR 0.96, 95% CI 0.93−0.99, p=0.003), and current smoking status (OR 2.34, 95% CI 1.14−5.30, p=0.022) were found to be significantly associated with severe CAD. Improvement of discrimination power for predicting severe CAD was observed when smoking and HDL cholesterol were serially added into the age model. CONCLUSION: Smoking showed significant correlations with moderate or severe CAD, and low HDL cholesterol also proved to be a predictor of severe CAD in asymptomatic individuals with extremely low CAC scores.

Large Coronary Artery Aneurysm with Thrombotic Coronary Occlusion Resulting in ST-Elevation Myocardial Infarction after Warfarin Interruption

A 44-year-old man, who had a history of myocardial infarction (MI) due to thrombotic occlusion of right coronary artery (RCA) aneurysm, visited emergency department presenting with ST-segment elevation myocardial infarction (STEMI). The patient had been on oral anticoagulant therapy (warfarin) from the first thrombotic event, but the medication had been recently changed to aspirin 4 months before the second event. Emergent coronary angiography revealed thrombotic total occlusion of RCA with heavy thrombotic burden from middle RCA to the ostium of the posterior descending branch. Combination pharmacotherapy was performed with anticoagulants (heparin), fibrinolytics (urokinase), and Glycoprotein IIb/IIIa antagonists (abciximab), in addition to mechanical thrombosuction. However, on hospital day 2, the patient complained recurrent chest pain and again underwent coronary angiography, which revealed distal embolization of large thrombus to the posterior lateral branch. Coronary flow was recovered after repeated mechanical thrombosuction was performed. This case has shown the importance of aggressive combination drug therapy, accompanied by mechanical thrombosuction in patient with myocardial infarction due to thrombotic occlusion of coronary artery aneurysm and the importance of unceasing life-long anticoagulant therapy in those particular patients.

Urinary Biomarkers for Early Detection of Recovery in Patients with Acute Kidney Injury

Urinary biomarkers of acute kidney injury (AKI) have been revealed recently to be useful for prior prediction of AKI. However, it is unclear whether these urinary biomarkers can also detect recovery from established AKI. Urinary biomarkers, including neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C, were measured every 2 days for 8 days in 66 patients with AKI. At day 0, there were no significant differences in plasma creatinine, BUN, and urine cystatin C between AKI patients in the recovery (n = 33) and non-recovery (n = 33) groups. Plasma creatinine concentrations were significantly lower in the recovery group (3.0 +/- 2.0 mg/dL) than in the non-recovery group (5.4 +/- 1.9 mg/dL) on day 4 after AKI diagnosis (P < 0.001). In contrast, there were significant differences in urine NGAL between the two groups starting on day 0 (297.2 +/- 201.4 vs 407.6 +/- 190.4 ng/mL, P = 0.025) through the end of the study (123.7 +/- 119.0 vs 434.3 +/- 121.5 ng/mL, P < 0.001). The multiple logistic regression analysis showed that urine NGAL could independently predict recovery from AKI. Conclusively, this prospective observational study demonstrates that urine NGAL can be a highly versatile marker for early detection of the recovery phase in established AKI patients.

A Thrombotic Coronary Artery Aneurysm Associated with Atherosclerosis in a Patient with End Stage Renal Disease / 대한신장학회지

We present a case of thrombotic coronary aneurysm of the left anterior descending artery (LAD) presenting with recurrent severe orthopnea in an end stage renal disease patient. She was admitted to the hospital with progressive dyspnea, exertional chest pain, and profound orthopnea. The echocardiography revealed a well marginated mass lesion between the main pulmonary artery and the left atrium. Chest CT showed a space-occupying lesion surrounded by the main pulmonary artery, the left atrium and the appendage adjacent to the atherosclerotic calcified lesion. Coronary angiography confirmed a huge thrombotic aneurysm with total occlusion of the proximal LAD. The presentation and management of the coronary aneurysm was reviewed.

Spontaneous Mediastinal Hemorrhage in a Patient with End Stage Renal Disease: An Unusual Case of Uremic Bleeding / 대한신장학회지

Hemorrhagic complications in patients with end stage renal disease (ESRD) are common. These abnormal bleeding tendencies are caused by several factors including anticoagulation during hemodialysis, anemia, and uremic platelet dysfunction. The most common clinical manifestation of uremic bleeding is hemorrhage of the gastrointestinal tract from gastric ulcer disease. Mediastinal bleeding, however, is rare in ESRD patients. Here, we report a case of spontaneous mediastinal bleeding in a patient with hemodialysis. A huge periesophageal hematoma was observed on the chest CT scan and the bleeding time representing platelet function was prolonged. This case underlies the diversity of uremic bleeding.

High-sensitivity C-reactive Protein Can Predict Major Adverse Cardiovascular Events in Korean Patients with Type 2 Diabetes

Inflammation is thought to play a role in the pathogenesis of major adverse cardiovascular events (MACE). It has been suggested that the measurement of markers of inflammation may aid in predicting the risk of such events. Here, the relationship between high-sensitivity C-reactive protein (hs-CRP) levels and MACE in Korean patients with type 2 diabetes is assessed. A retrospective cohort study was conducted as a follow-up among 1,558 patients with type 2 diabetes and without cardiovascular diseases over a mean period of 55.5 months. A Cox proportional-hazards model was used to determine whether increased hs-CRP levels are useful as a predictor for future MACE. The hazard ratio of MACE was 1.77 (95% CI; 1.16-2.71) in subjects who had the highest hs-CRP levels (> 0.21 mg/dL) compared to subjects who had the lowest hs-CRP levels (< 0.08 mg/dL), after adjusting for age, regular physical activity, current smoking, and duration of diabetes. The present results indicate that high hs-CRP levels can act as a predictor for the MACE occurrence in Korean patients with type 2 diabetes.

Unusual Presentation Chronic Pulmonary Embolism due to Calcified Right Ventricular Mass

Cardiac calcified amorphous tumors (CATs) can arise in all four chambers of the heart. Cardiac CATs can cause diverse symptoms according to their locations, and mass or embolic effects. Pulmonary emboli arising from cardiac CATs have been reported, but the true incidence is unknown due to their rarity. Herein we report a rare case with diffuse CATs in the right ventricle which caused a calcific pulmonary embolism and right-sided heart failure. Echocardiography, chest non-contrast computed tomography, and cardiac magnetic resonance imaging helped us diagnose the CATs. We recommend the usefulness of a multimodality imaging approach to characterize intracardiac masses and their complications accurately.

Tuberculous Peritonitis in a Patient with Rheumatoid Arthritis Treated with Infliximab

One of the severe adverse reactions to anti-tumor necrosis factor (TNF)-alpha therapy is the reactivation of tuberculosis. We present a case of tuberculous peritonitis in a 57-year-old woman with rheumatoid arthritis (RA) that appeared during treatment with infliximab. Confirming a diagnosis of tuberculous peritonitis is difficult and can be delayed because of the nonspecific symptoms, the rarity of the disease and the low detection rate of mycobacteria in ascites fluid. This case illustrates that prompt anti-tuberculous therapy is needed for suspected cases of tuberculous peritonitis in RA patients treated with infliximab.

A Case of Replacement Lipomatosis of Allograft Kidney Presented with Deep Vein Thrombosis / 대한신장학회지

Replacement lipomatosis of the kidney is a rare disorder in which a massive fatty tissue proliferation occurs within the renal sinus, hilum and perirenal region. Clinical symptoms includes flank pain, hematuria, fever usually associated with urinary tract infection and renal stone. But deep vein thrombosis due to mass effect has not been reported to be associated with replacement lipomatosis of kidney. A 37-year-old male was referred for the initiation of hemodialysis due to chronic rejection of allograft kidney. Collateral superficial veins were observed on his anterior abdominal wall and firm mass was palpable in the right lower quadrant abdomen. Abdominal-pelvis computed tomography revealed huge fatty mass originated from allograft kidney and non-visualization of inferior vena cava with lower density thrombus at both the common femoral veins. We report a rare case of replacement lipomatosis of the kidney complicated by deep vein thrombosis after renal transplantation.

A Case of Ectopic Sebaceous Glands in the Esophagus / 대한소화기내시경학회지

A 42-year-old man without any signs or symptoms of illness underwent esophagogastroduodenoscopy (EGD) for a routine health check up. On esophagogastroduodenoscopy, multiple small and yellowish mucosal plaques were detected in the mid to distal esophagus. These plagues proved to be ectopic sebaceous glands of the esophagus according to the histologic examination. On the immunohistochemical staining with anti-Keratin 14, the basal cells and the heterotopic sebaceous glands were immunoreactive for keratin 14. The histogenesis of this extremely rare lesion is not completely clear. There have been some reports on ectopic esophagus sebaceous glands combined with esophageal cancer or gastric cancer. However, malignant transformation of the ectopic sebaceous gland itself has not yet been reported on. This case was regularly followed up for 12 months, and no interval change or malignant transformation was found both endoscopically and histologically.

Relationship between Diabetic Retinopathy and Arteriolosclerosis in Patients with NIDDM (Non-insulin-dependent diabetes mellitus)

PURPOSE: To evaluate the correlation between diabetic retinopathy (DR) and arteriolosclerosis in patients with NIDDM (non-insulin-dependent diabetes mellitus), to investigate the risk factors of DR, and to assess the change of the correlation according to the risk factors. METHODS: The study subjects were selected from consecutive routine clinical visits by random sampling from July 2002 to June 2003. The patients were divided into two groups according to the presence of DR, and the patients' charts, fundus examination and blood test were retrospectively reviewed. ETDRS (Early Treatment DR Study) classification for DR and Scheie classification for arteriolosclerosis were used. Statistical analysis was conducted with SPSS program (version 10.0). The confidence interval was set to 95%, and the level of significance was set at p=0.05. RESULTS: DR had a statistically significant correlation with arteriolosclerosis, especially according to duration of diabetes mellitus (p<0.05). Risk factors including diabetes mellitus duration, HgA1c level, and LDL (low-density lipoprotein) cholesterol level showed statistically significant difference (p<0.05). CONCLUSIONS: From the result of analysis, DR has a statistically significant correlation with arteriolosclerosis, especially according to the duration of diabetes mellitus. To prevent vision-threatening complications of DR, the degree of arteriolosclerosis as well as risk factors such as diabetes mellitus duration, serum HgA1c level, and LDL (low-density lipoprotein) cholesterol level should be carefully considered and monitored in the evaluation, progression, and treatment of DR.

A Case of Vitreous Amyloidosis

PURPOSE: To report a case of vitreous amyloidosis. METHODS: A 51-year old male presented with bilateral floater and decreased visual acuity of 3 months duration. Small white dots attached to the posterior lens surface were observed on slit lamp examination. The vitreous opacity, which connected with the small white dots to the posterior lens surface, were observed on funduscopic examination, and multiple hyperechoic plaques in the vitreous cavity on B-scan. The pars plana vitrectomy was performed. RESULTS: The aspirate of the pars plana vitrectomy was stained with Congo red and observed with light microscope, and polarized light. Electron microscopy was also performed. The vitreous smear stained with Congo red showed greenish dichroism and birefringent nature with polarized light and fine fibrillar nature of amyloid material was noted on electron microscopy. CONCLUSIONS: To our knowledge, this is the first Korean report of vitreous amyloidosis. The authors diagnosed vitreous amyloidosis that developed in a 51-year-old male patient. The diagnosis was confirmed by light microscope, polarized light and electron microscope.

The Evaluation of Contrast Sensitivity and Glare after LASIK Using Flying Spot Mode Laser According to Pupil Diameter and Refractive Error

PURPOSE: To study the effect of LASIK using flying spot mode laser on contrast sensitivity and glare according to pupil diameter and preoperative refractive error. METHODS: Fifty seven eyes of 42 patients had LASIK using MEL 70 G-scan (Asclepion Meditec, Germany) to correct myopia ranging from -2.50 to -10.50 diopter (D). The contrast and glare sensitivity were measured preoperatively and 1 week, 1 month and 3 months after LASIK using CGT-1000 (Takagi, Japan). RESULTS: The mean preoperative spherical equivalent (SE) was -5.4+/-2.9D. The mean pupil diameter was 5.95+/-0.46 mm in scotopic condition. Contrast sensitivity was significantly reduced 1 month after LASIK, depending on pupil diameter and degree of preoperative myopia. However, values returned to preoperative figures thereafter (P<0.05). Glare sensitivity was improved at all frequencies 3 months after LASIK, and most significantly at high frequency (P=.031). CONCLUSIONS: LASIK using employing the flying spot mode laser can effectively accomplish refractive correction without reduction of preoperative contrast and glare sensitivity values.