Utilizing Deep Learning and Computed Tomography to Determine Pulmonary Nodule Activity in Patients With Nontuberculous Mycobacterial-Lung Disease.

PURPOSE: To develop and evaluate a deep convolutional neural network (DCNN) model for the classification of acute and chronic lung nodules from nontuberculous mycobacterial-lung disease (NTM-LD) on computed tomography (CT). MATERIALS AND METHODS: We collected a data set of 650 nodules (316 acute and 334 chronic) from the CT scans of 110 patients with NTM-LD. The data set was divided into training, validation, and test sets in a ratio of 4:1:1. Bounding boxes were used to crop the 2D CT images down to the area of interest. A DCNN model was built using 11 convolutional layers and trained on these images. The performance of the model was evaluated on the hold-out test set and compared with that of 3 radiologists who independently reviewed the images. RESULTS: The DCNN model achieved an area under the receiver operating characteristic curve of 0.806 for differentiating acute and chronic NTM-LD nodules, corresponding to sensitivity, specificity, and accuracy of 76%, 68%, and 72%, respectively. The performance of the model was comparable to that of the 3 radiologists, who had area under the receiver operating characteristic curve, sensitivity, specificity, and accuracy of 0.693 to 0.771, 61% to 82%, 59% to 73%, and 60% to 73%, respectively. CONCLUSIONS: This study demonstrated the feasibility of using a DCNN model for the classification of the activity of NTM-LD nodules on chest CT. The model performance was comparable to that of radiologists. This approach can potentially and efficiently improve the diagnosis and management of NTM-LD.

Usefulness of laboratory parameters and chest CT in the early diagnosis of COVID-19.

In the present study, the importance of laboratory parameters and CT findings in the early diagnosis of COVID-19 was investigated. To this end, 245 patients admitted between April 1st, and May 30th, 2020 with suspected COVID-19 were enrolled. The patients were divided into three groups according to chest CT findings and RT-PCR results. The non-COVID-19 group consisted of 71 patients with negative RT-PCR results and no chest CT findings. Ninety-five patients with positive RT-PCR results and negativechest CT findings were included in the COVID-19 group; 79 patients with positive RT-PCR results and chest CT findings consistent with COVID-19 manifestations were included in COVID-19 pneumonia group. Chest CT findings were positive in 45% of all COVID-19 patients. Patients with positive chest CT findings had mild (n=30), moderate (n=21) andor severe (n=28) lung involvement. In the COVID-19 group, CRP levels and the percentage of monocytes increased significantly. As disease progressed from mild to severe, CRP, LDH and ferritin levels gradually increased. In the ROC analysis, the area under the curve corresponding to the percentage value of monocytes (AUC=0.887) had a very good accuracy in predicting COVID-19 cases. The multinomial logistic regression analysis showed that CRP, LYM and % MONO were independent factors for COVID-19. Furthermore, the chest CT evaluation is a relevant tool in patients with clinical suspicion of COVID-19 pneumonia and negative RT-PCR results. In addition to decreased lymphocyte count, the increased percentage of monocytes may also guide the diagnosis.

Right Ventricular Blood Cyst in an Adult Autosomal Dominant Polycystic Kidney Disease Patient: An Unusual Association.

Blood cysts of the heart are unusual primary cardiac tumor-like masses, which are usually located on the cardiac valves. These are very rare in adults, especially in a non-valvular location. Autosomal-dominant polycystic kidney disease (ADPKD) typically presents with multiple bilateral renal cysts, resulting in chronic kidney disease. Whilst many of the extra-renal manifestations of ADPKD are well-documented, associated cardiac masses are extremely rare: and cardiac blood cyst has not been reported in a patient with APKD to date. We present a 57-year man with a history of ADPKD and end-stage renal disease with a 2-cm-diameter right ventricular blood cyst, which was detected on multimodality imaging. Key words: Autosomal dominant polycystic kidney disease, Cardiac blood cyst, Extra-renal manifestations.

The diagnostic and prognostic value of the optic nerve sheath diameter on CT for diagnosis spontaneous subarachnoid hemorrhage.

INTRODUCTION: The aim of this study was to investigate the relationship between the optic nerve sheath diameter (ONSD) measured on non-contrast head computed tomography (CT) and the diagnosis and prognosis of spontaneous subarachnoid hemorrhage (SAH) on emergency department (ED) patients. METHOD: We used a matched control group of patients with the same age and gender who were diagnosed in the ED with spontaneous SAH and who admitted to the ED with headache. Four emergency medicine attending physicians made the ONSD measurements. For measurements, the 3-mm posterior location where the optic nerve enters the eyeball was used. RESULTS: This study was done with 61 spontaneous SAHs with an equal number of control patients. The median ONSD for control and spontaneous SAH groups was 5.76 [interquartile range (IQR): 0.96] mm and 6.72 (IQR: 1.42) mm, respectively (p<0.001). The area under the receiver operating characteristic curve was determined as 0.791 (confidence interval 95% 0.710-0.872). At an ONSD threshold value of 6.1 mm, the sensitivity and specificity of SAH was 72%. There was no significant relationship between ONSD and in-hospital mortality in spontaneous SAH patients (p>0.05). The intra-class correlation coefficients for inter and intra-rater reliability were 0.84 and 0.95, respectively. CONCLUSION: In patients with spontaneous SAH, the ONSD measured in the orbital sections of a head CT is strongly correlated with a SAH diagnosis. Assessment of ONSD in head CTs taken with spontaneous SAH suspicion may contribute to the diagnoses of spontaneous SAH.

Dural puncture: an overlooked cause of cerebral venous thrombosis.

Cerebral venous thrombosis (CVT) accounts for 0.5-1 % of all strokes. Although dural puncture is proposed as one of the rare risk factors, this association has only been mentioned in anecdotal reports. Headache, i.e., usually the first and the most frequent clinical symptom on admission, is often attributed to the dural puncture itself. We investigated the frequency of CVT following a recent dural puncture in our stroke database, together with the other risk factors. The computerized medical records of patients (n = 10,740) registered in our tertiary-care neurology clinic stroke database were reviewed retrospectively. Patients diagnosed with CVT were reanalyzed. Patients who had a dural puncture in the preceding 7 days were included in the study. A total of 46 patients were diagnosed with CVT. Nine patients (19.6 %) had a recent dural puncture before the onset of the symptoms. Patients were younger than 45 years and had at least one more predisposing condition for thromboembolism other than the dural puncture. All patients have received either spinal anesthesia or intrathecal chemotherapy. Dural puncture seems to trigger CVT particularly in patients with predisposing disorders. Although reported as an extremely rare complication, our data indicate a much higher association. This case series emphasize the importance of reevaluation of patients with persistent/progressive headache following dural puncture. The effect of change in the biochemical composition of CSF due to intrathecal drug administration in pathogenesis is not known. Larger controlled trials are warranted to clarify the causal relationship between lumbar puncture and/or intrathecal drug administration and CVT.

The prevalence and extent of coronary atherosclerosis among patients with a zero calcium score and the influence of patient characteristics.

PURPOSE: Coronary artery calcium (CAC) is a specific indicator of and an independent risk factor for atherosclerosis; however, calcium scoring may miss noncalcified plaques, which may have clinical importance. The aim of this study was both to identify the presence and extent of coronary plaques during computed tomography coronary angiography (CTCA) in patients with a zero CAC score and to evaluate the effect of risk factors and symptom status on the presence of noncalcified plaques. MATERIALS AND METHODS: In this retrospective study, we analyzed the cases of 842 consecutive patients between October 2006 and November 2011. Of these patients, we included 357 with a zero calcium score in the study. Information regarding patient age, sex, coronary risk factors, and symptom status were recorded. Coronary calcium-scoring scans were followed by CTCA. The calcium scores were calculated, and the presence of noncalcified plaques and significant stenoses (>50% of vessel diameter) was evaluated. RESULTS: Of the 357 patients with a zero calcium score, 37 (10.36%) had atherosclerotic plaques; 9 patients (2.52%) had significant coronary stenosis. Among coronary risk factors, only diabetes mellitus was significantly correlated with any risk factors (presence of atherosclerosis and obstructive coronary artery disease; P = .030 and .013, respectively). CONCLUSION: Although CAC scoring is a safe and a reliable test to exclude obstructive coronary artery disease, the absence of CAC does not definitively exclude the presence of atherosclerosis. CTCA is a more appropriate method for determining the atheroma burden.

Anomalous Origin of the Left Coronary Artery from the Pulmonary Artery: Diagnosis with CT Angiography.

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital anomaly. It is associated with early infant mortality and sudden death in adults. Traditionally, ALCAPA has been diagnosed by angiography or autopsy; however, the development of cardiac computed tomography (CT) and magnetic resonance imaging (MRI) has allowed noninvasive evaluation of the coronary anatomy by direct visualization of the origin of the left coronary artery (LCA) from the pulmonary artery. We report a case of 10-year-old girl who has been on follow up for dilated cardiomyopathy for 4 years. The definitive diagnosis of ALCAPA is reached by multislice computed tomography (MSCT). The MSCT scan showed an anomalous origin of LCA from the pulmonary trunk, with a tortuous and dilated right coronary artery and right-to-left collateralization. Consequently, the patient was successfully treated with surgery.

Colloid cyst of the third ventricle associated with anterior cerebral artery trifurcation and agenesis of the corpus callosum: findings on MRI and CT angiography.

We report MRI with diffusion-weighted imaging, and multidetector CT angiography findings in a child with complete agenesis of the corpus callosum associated with a colloid cyst and trifurcation of the anterior cerebral artery. Although rare, a colloid cyst should be considered in the differential diagnosis of midline lesions in children with agenesis of the corpus callosum since it may require surgical intervention.

A rare coronary artery anomaly: double left anterior descending artery.

Double left anterior descending coronary artery arising from the left and right coronary arteries is one of the rarest of coronary anomalies. In this report, we present a case of double left anterior descending coronary artery with one originating from the left main stem and the second one originating from the same ostium with the right coronary artery, passing to the left side following an inter-arterial course between aorta and right ventricular outflow tract and spreading to the anterior wall of the left ventricle. The diagnosis was made with multislice computed tomography angiography. To our knowledge, only a few such cases have been published in the literature so far.

The contribution of MR coronary angiography to the diagnosis of a left anterior descending artery aneurysm in a patient with Kawasaki disease.

We present a 4-year-old boy with a diagnosis of Kawasaki disease of six-month history. At the time of diagnosis, no significant coronary artery aneurysm was detected by transthoracic echocardiography. On his routine follow-up echocardiography, dilatation of the left anterior descending (LAD) artery was suspected, but an exact diagnosis could not be made. He underwent magnetic resonance (MR) coronary angiography which showed a large fusiform aneurysmatic dilatation in the proximal segment of the LAD with a diameter of 9 mm. Coronary angiography performed to plan surgical repair confirmed the findings of MR angiography. The patient's parents refused surgical repair, so antiplatelet therapy was started to prevent thrombosis. No complications occurred during seven months of follow-up after detection of the aneurysm.

Accuracy of MR coronary angiography in the evaluation of coronary artery stenosis.

PURPOSE: To examine the accuracy of magnetic resonance (MR) coronary angiography for the evaluation of coronary artery stenoses, and to compare the results with conventional angiography as the reference standard. MATERIALS AND METHODS: Eighteen patients were examined. The pulse sequence was an ECG-triggered, T2-prepared, fat-suppressed 3D true fast imaging with steady state precession sequence with navigator respiratory gating. No contrast material was used. The 3D slabs were oriented axially, covering the whole heart. The MR images were evaluated for the presence of stenoses exceeding 50% luminal narrowing. The diagnostic accuracy of MR angiography was calculated, and was compared with conventional coronary angiography. All patients gave informed consent, and the study was approved by the institutional ethics committee. RESULTS: In conventional angiography, 16 stenoses were detected in 11 patients, and 7 patients were normal. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of MR coronary angiography for detecting coronary stenosis on segment-based analysis were 75%, 98%, 80%, 97%, and 96%, respectively. McNemar test demonstrated no significant difference between MR and conventional angiography (P = 0.62). CONCLUSION: MR coronary angiography is a non-invasive diagnostic method currently in a state of evolution. It has limitations, but can be regarded as an alternative noninvasive modality to detect coronary artery disease in selected patient in whom invasive angiography may be hazardous.

Evaluation of coronary stent patency and in-stent restenosis with dual-source CT coronary angiography without heart rate control.

OBJECTIVE: Dual-source CT has excellent temporal resolution and allows good visualization of coronary vessels without heart rate control. Our aim was to evaluate the diagnostic performance of dual-source CT in the evaluation of coronary stent patency to determine whether the good temporal resolution would improve visualization of stents. SUBJECTS AND METHODS: Thirty-five consecutively registered patients (10 women, 25 men; mean age, 65 years) with 48 stents were examined prospectively without heart rate controlling agents. Observers evaluating image quality and patency of the stents were blinded to the results of invasive coronary angiography. In-stent restenosis was defined as more than 50% narrowing of the lumen. RESULTS: All stents were considered assessable for diagnosis with dual-source CT. In 85% (41/48) of the stents, image quality was good. Only two patent stents were misidentified as being stenotic. All other stents with stenosis and occlusion were correctly diagnosed. The sensitivity, specificity, positive and negative predictive values, and accuracy of dual-source CT in the detection of in-stent restenosis and occlusion were 100%, 94%, 89%, 100%, and 96%, respectively. The McNemar test result showed no statistically significant difference between the diagnostic performance of dual-source CT and that of invasive coronary angiography. The kappa indexes showed excellent intraobserver and interobserver agreement. CONCLUSION: The high temporal resolution of dual-source CT is helpful for evaluation of coronary stents without heart rate control. Further confirmation of our preliminary results may broaden the clinical indications for CT angiography as a diagnostic test for the exclusion of in-stent restenosis.

An aneurysmal left circumflex artery-to-right atrium fistula in a patient with ischemic symptoms: accurate diagnosis with dual-source CT angiography.

In this report, we present a 55-year-old female patient with a left circumflex artery-to-right atrial fistula associated with a huge saccular aneurysm. She had undergone conventional angiography due to ischemic symptoms. In conventional angiography, a very dilated and tortuous vessel originating from the circumflex artery and continuous with a huge saccular aneurysm was visualized but the drainage site could not be demonstrated. With dual-source CT coronary angiography, the exact anatomy of this fistula was demonstrated and surgery was planned.

Effectiveness of dual-source CT coronary angiography for the evaluation of coronary artery disease in patients with atrial fibrillation: initial experience.

PURPOSE: To prospectively evaluate the sensitivity and specificity of dual-source CT for significant coronary stenosis (>50% narrowing) in patients with atrial fibrillation (AF), by using conventional coronary angiography as the reference standard. MATERIALS AND METHODS: Institutional Review Board approval and informed consent were obtained. Fifteen consecutive patients (nine men, six women; mean age, 58.47 years) were examined. Image quality (good, moderate, or poor) and significant stenosis (>50%) were evaluated by two radiologists blinded to the conventional coronary angiography results. Sensitivity, specificity, positive predictive value (PPV), and negative predictive values (NPV) were calculated. McNemar test was used to search for any significant difference between dual-source CT and conventional coronary angiography in helping detect coronary stenosis. kappa statistics were calculated for intermodality and interobserver agreement. RESULTS: Sixteen segments by reader 1 and 13 segments by reader 2 were considered as poor image quality and rejected for further analysis. All segments with good image quality were correctly diagnosed. The respective overall sensitivity, specificity, PPV, and NPV values were 87%, 98%, 77%, and 99% for reader 1 and 80%, 99%, 80%, and 99% for reader 2. No significant difference between dual-source CT and conventional coronary angiography was found in helping detect significant stenosis. kappa statistics demonstrated good intermodality and excellent interobserver agreement. CONCLUSION: Dual-source CT technology provides a temporal resolution that allows CT coronary angiography at higher heart rates and even with AF.

Contrast-enhanced 64-slice computed tomography in detection and evaluation of anomalous coronary arteries.

Anomalous coronary artery (ACA) has either an unusual origin or different anatomical course and is associated with sudden cardiac death. The absence or nonspecific symptoms of ACA make its diagnosis difficult. Mostly, ACA is diagnosed coincidentally during invasive coronary angiogram (ICA). A conventional computed tomography (CT) cannot provide detailed images of coronary arteries of the moving heart, but 64-slice CT, with its short acquisition time, can provide detailed anatomy of coronary arteries non-invasively. In this study, we assessed the validity of contrast-enhanced 64-slice CT in the evaluation of ACA. ICA was performed in 7,574 patients for the diagnosis or evaluation of occlusive coronary artery disease and detected coronary anomalies in 56 patients (0.7%). We then performed 64-slice CT in 53 patients out of the 56 patients with demonstrated or suspected coronary anomaly, showing the origin and the course of the ACA along with stenosis, except for one patient who could not be evaluated due to image distortion artifacts. Contrast-enhanced 64-slice CT was also performed in 374 patients with vague signs and symptoms, detecting coronary anomalies in 7 patients (1.2%). Thus, in the total of 59 patients undergone 64-slice CT, we were able to visualize the entire abnormal coronary tree with a high diagnostic image quality. This is the first study to demonstrate the utility of 64-slice CT in a large series of ACA. Contrast-enhanced 64-slice CT is superior to ICA to identify the presence and course of ACA and should be the first line diagnostic tool in the evaluation of ACA.

Detection of significant coronary artery stenosis with 64-section MDCT angiography.

PURPOSE: To prospectively evaluate the diagnostic performance of 64-section multidetector computed tomography (MDCT) to detect significant coronary artery stenosis using conventional coronary angiography (CCA) as the reference standard. MATERIALS AND METHODS: Institutional Review Board approval and informed consent were obtained. In this prospective study, 80 patients (61 male, 19 female, mean age 56) were examined. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were calculated. McNemar test was used to search for the significant difference between 64-section MDCT angiography and CCA to detect stenosis. Also, kappa index (kappa) for the agreement between MDCT angiography and CCA was calculated. RESULTS: The sensitivity, specificity, positive (PPV) and negative predictive values (NPV) for detecting significant stenosis were 96%, 98%, 91%, 99%, respectively. The sensitivity, specificity, PPV and NPV for classification of patients with or without CAD were 100% for all. McNemar test demonstrated no significant difference between 64-section MDCT angiography and CCA. Also, kappa index (kappa) indicated excellent agreement. CONCLUSION: Sixty-four section MDCT angiography is an effective diagnostic tool for the detection of significant coronary artery stenosis. Especially, the potential to differentiate patients with and without CAD may provide MDCT an important role in the prevention of unnecessary invasive diagnostic procedures.

Coronary stent patency and in-stent restenosis: determination with 64-section multidetector CT coronary angiography--initial experience.

PURPOSE: To prospectively assess the diagnostic performance of 64-section multidetector computed tomography (CT) for the evaluation of coronary stent stenosis and occlusion by using conventional coronary angiography as the reference standard. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. Thirty patients (27 men, three women; mean age, 58.2 years; range, 42-67 years) with 39 coronary stents were examined with 64-section multidetector CT. Scanning was retrospectively electrocardiographically gated, and an automatic bolus-tracking method was used. For image reconstruction, an edge-enhancing kernel (B46f) was chosen. Evaluations were performed by two radiologists who were blinded to the results of conventional coronary angiography performed within 2-3 days after CT. Sensitivity, specificity, and positive and negative predictive values were calculated. RESULTS: At conventional angiography, nine of the 39 stents were shown to be totally occluded. All of the occluded stents were correctly diagnosed with CT angiography. Nineteen of 20 patent stents were correctly demonstrated with CT angiography. Ten stents had in-stent restenosis; eight were correctly diagnosed with CT. The sensitivity, specificity, and positive and negative predictive values of 64-section multidetector CT were 89% (17 of 19), 95% (19 of 20), 94% (17 of 18), and 90% (19 of 21), respectively, for in-stent restenosis and occlusion. With the McNemar test, no significant difference was found between 64-section multidetector CT and conventional coronary angiography for the detection of coronary in-stent restenosis and occlusion. CONCLUSION: Sixty-four-section multidetector CT coronary angiography is a promising method for the noninvasive diagnosis of in-stent restenosis and occlusion.

Right coronary artery to left ventricle fistula--effective diagnosis with 64-MDCT.

Coronary artery fistula is a rare congenital anomaly in which a communication is present between a cardiac chamber or another vascular structure. In this paper, we describe a 52-year-old asymptomatic male patient with a right coronary artery to left ventricle fistula. We demonstrate the effectiveness of 64-MDCT (Multi-detector row computed tomography) in demonstrating the precise anatomy of this fistula in which transthoracic echocardiography was inadequate for evaluation.