Artificial intelligence in cardiac computed tomography.

Artificial Intelligence (AI) is a broad discipline of computer science and engineering. Modern application of AI encompasses intelligent models and algorithms for automated data analysis and processing, data generation, and prediction with applications in visual perception, speech understanding, and language translation. AI in healthcare uses machine learning (ML) and other predictive analytical techniques to help sort through vast amounts of data and generate outputs that aid in diagnosis, clinical decision support, workflow automation, and prognostication. Coronary computed tomography angiography (CCTA) is an ideal union for these applications due to vast amounts of data generation and analysis during cardiac segmentation, coronary calcium scoring, plaque quantification, adipose tissue quantification, peri-operative planning, fractional flow reserve quantification, and cardiac event prediction. In the past 5 years, there has been an exponential increase in the number of studies exploring the use of AI for cardiac computed tomography (CT) image acquisition, de-noising, analysis, and prognosis. Beyond image processing, AI has also been applied to improve the imaging workflow in areas such as patient scheduling, urgent result notification, report generation, and report communication. In this review, we discuss algorithms applicable to AI and radiomic analysis; we then present a summary of current and emerging clinical applications of AI in cardiac CT. We conclude with AI's advantages and limitations in this new field.

Traumatic aortic injury from pellet gun: A case report.

Acute traumatic aortic injuries are of the most lethal sequelae of penetrating thoracic injuries and require rapid detection and management. The American College of Radiology currently recommends the use of noncontrast CT, followed by computed tomography angiography (CTA) as the first-line imaging modalities when traumatic aortic injury is suspected. Direct signs of aortic injury on CTA include pseudoaneurysm, focal contour abnormality, intimal flap, intramural hematoma, an abrupt change in aortic caliber, and contrast extravasation. Aortic pseudoaneurysms are most often caused by blunt or penetrating trauma that results in damage to the vessel wall, turbulent blood flow, and formation of a surrounding hematoma contained by a wall of products from the clotting cascade. This wall is weaker than those of a true aneurysm and will ultimately rupture over time if not repaired. Traumatic aortic pseudoaneurysms are preferably treated by thoracic endovascular aortic repair using a prosthetic stent graft. Here, we present a 44-yearold female with a history of homelessness, polysubstance use disorder, and HIV who presented to the emergency department after being found down. She reported being shot by a pellet gun, and physical examination revealed a penetrating left-sided chest wound that appeared to be several days old. A STAT CTA was obtained and revealed a hemopneumothorax and possible thoracic aortic pseudoaneurysm. A left-sided chest tube was placed and the patient underwent thoracic endovascular aortic repair through right femoral arterial access and tolerated the procedure well. The patient was placed on daily aspirin postoperatively and discharged on post-op day 5.

Cardiac MR imaging reveals L-type transposition of the great vessels and failing right heart.

L-type transposition of the great vessels is a rare congenital heart disease in which both the great arteries and the ventricular chambers are reversed. Because this condition preserves a physiologic circulatory pathway, it can be challenging to diagnose in infants with no concurrent cardiac abnormalities. Early detection is essential, however, because these patients will eventually experience severe complications, as the structural right ventricle is unable to function long-term in the systemic position. We report a rare case of L-type transposition of the great vessels in a 32-year-old male who presented in adulthood with tachycardia and palpitations. The initial echocardiogram was inconclusive. Further imaging (cardiac MRI & transesophageal echocardiogram) revealed the inverted anatomy due to the presence of key morphological features, such as the malposed great vessels along with the moderator band and prominent trabeculae within the right ventricle, which was functioning systemically.

Correction to: CT angiograms of the neck in strangulation victims: incidence of positive findings at a level one trauma center over a 7-year period.

The original source of the flowchart in Fig. 3 has not been referenced and acknowledged correctly in the original article. This is now corrected.

CT angiograms of the neck in strangulation victims: incidence of positive findings at a level one trauma center over a 7-year period.

PURPOSE: To determine the incidence of acute findings diagnosed with computed tomography angiography (CTA) of the neck among emergency department patients presenting with strangulation injury. METHOD AND MATERIALS: This institutional review board-approved, HIPAA-compliant retrospective review was performed at our academic urban level 1 trauma center. The PACS database was queried for all consecutive patients who had CTAs of the neck performed for the exam indication of strangulation between January 1, 2009, and April 30, 2016, resulting in 142 included patients. Analysis of the individual cases was then performed, recording any positive results, with clinical findings classified using, when possible, standardized terminology found in the literature. Frequency of acute injury in the CTA neck examinations was determined with the calculation of 95% confidence interval (CI) and positive clinical findings were evaluated by calculation of prevalence. Additionally, two board certified radiologists with training in neuroradiology assessed the cases for vascular injury. RESULTS: There were 142 patients who met inclusion criteria (average age, 32.6 years) and 116 (81.7%) patients were female. CTA of the neck revealed 21 patients to have acute injuries (15.5%, 95% CI 9.5, 21.4) including 6 initially reported vascular injuries (4.2%, 95% CI 0.9, 7.5). Although neck pain (73, 51.4%), loss of consciousness (67, 47.2%), and headache (31, 21.8%) were frequently reported in the ROS, their predictive value of vascular injury was weak (4.1%, 4.5%, and 3.2%, respectively). On physical exam, redness/bruising of the neck (73, 51.4%) and neck tenderness (47, 33.1%) were both the most common and had the highest prevalence (19.2% and 12.8%, respectively), however, when selecting for vascular injuries alone were found to have low predictive yield (vascular injury 4.1% and 2.1%, respectively). The above statistics were based on the initial radiologist report and Emergency Department findings. After retrospective review, 3 Grade 1 BIFFL vascular injuries were identified (2.1%), with one false negative case (0.7%). CONCLUSION: Performing CTA of the neck after acute strangulation injury rarely identifies clinically significant findings, with vascular injuries proving exceedingly rare. As positive vascular injury could not be clinically predicted by history and physical examination, prospective validation of a clinical prediction rule in this population is warranted.

Situs ambiguous, levocardia, right sided stomach, obstructing duodenal web, and intestinal nonrotation: a case report.

When approaching a case with a situs abnormality, using the proper terminology, making a specific diagnosis, and understanding the other often associated abnormalities that need to be excluded are of great importance. We present a case of situs ambiguous in the presence of intestinal nonrotation and an obstructing duodenal web. Our patient initially presented at two days old with bilious emesis and failure to pass meconium after birth. An abdominal radiograph demonstrated an unusual bowel gas pattern, a reversed "double bubble" sign. A subsequent thorough imaging survey was crucial to further characterize our patient's unique anatomy. Overall, our case demonstrates many of the unusual plain radiographic and sonographic findings associated with our patient's situs abnormality and allows for review of situs abnormalities and their significance.

Role of nuclear medicine imaging in recognizing different causes of osteonecrosis of the jaw.

The incidence of osteonecrosis of the jaw (ONJ) among patients with cancer and metastatic bone disease being treated with bisphosphonates is as high as 10%, which dictates that an understanding of the risk factors, preventative measures, means of early diagnosis, and treatment is critical. Despite ONJ occurring in the clinical setting of intravenous bisphosphonates, there are other causes associated with higher risk of ONJ, such as multiple dental extractions. Overall, it is important for imaging health care professionals to recognize, describe, and understand ONJ to help minimize biopsies and allow proper treatment to begin as soon as possible.

Coronary artery fistula: 64-slice computed tomographic delineation and correlation with multiplane transesophageal echocardiography and surgical findings.

A 49-year-old female who presented with 3 weeks of exertional chest pain had an abnormal mediastinal finding at chest x-ray imaging. Conventional, nongated computed tomography of the chest revealed a "mass" in proximity to the right atrium. 64-slice, cardiac gated computed tomographic coronary angiography, and transesophageal echocardiography delineated the "mass" as a coronary artery fistula structure. The fistula originated from the left main as a tubular vessel that continued into an aneurysmal sac-like cavity that emptied into the superior vena cava near the right atrium. Computed tomographic coronary angiography showed otherwise normal coronary arteries. Findings were ultimately confirmed at cardiac catheterization. Coronary steal was clinically diagnosed and she underwent surgical ligation and resection of the fistula and aneurysm. Her subsequent course was uncomplicated.

Hepatic intra-arterial injection of drug-eluting bead, irinotecan (DEBIRI) in unresectable colorectal liver metastases refractory to systemic chemotherapy: results of multi-institutional study.

INTRODUCTION: Response rates and overall outcome for patients who have failed first-line and in some cases second-line chemotherapy are as low as 12% and 7 months, respectively. The aim of this study is to evaluate the efficacy of hepatic arterial sulfonate hydrogel microsphere (drug-eluting beads), irinotecan preloaded therapy (DEBIRI) in metastatic colorectal cancer refractory to systemic chemotherapy. METHODS: This was a multicenter multinational single-arm study of metastatic colorectal cancer patients who received DEBIRI after failing systemic chemotherapy from 10/2006 to 8/2008. Primary endpoints were safety, tolerance, tumor response rates, and overall survival. RESULTS: Fifty-five patients who had received prior systemic chemotherapy and who underwent a total of 99 DEBIRI treatments were reviewed. The median number of DEBIRI treatments was 2 (range 1-5), median treatment dose was 100 mg (range 100-200 mg), with total hepatic treatment of 200 mg (range 200-650 mg), with 86% of treatments performed as lobar infusion and 30% of patients treated with concurrent simultaneous chemotherapy. Adverse events occurred in 28% of patients with median grade of 2 (range 1-3) with no deaths at 30 days post procedure. Response rates were 66% at 6 months and 75% at 12 months. Overall survival in these patients was 19 months, with progression-free survival of 11 months. CONCLUSIONS: Hepatic arterial drug-eluting bead, irinotecan (DEBIRI) was safe and effective in treatment of metastatic colorectal cancer (MCC) refractory to multiple lines of systemic chemotherapy. DEBIRI is an acceptable therapy for treatment of metastatic colorectal cancer to the liver.

A directionally-selective neuromorphic circuit based on reciprocal synapses in Starburst Amacrine Cells.

Starburst Amacrine Cells (SACs) play a major role in the detection of directional motion in the biological retina. The starburst amacrine cell has intrinsic electrical mechanisms for producing directional selectivity (DS). GABA transmitter-receptor interactions between two overlapping SACs make DS more robust. We present a compartmentalized CMOS neuromorphic circuit that models a portion of two biological starburst amacrine cells in the retina and includes a simplified model of reciprocal interaction between the dendritic branches of SACs. We demonstrate that a neuromorphic circuit incorporating the reciprocal synapses enhances the responses in the neuromorphic dendritic tip and generates robust directional selectivity.

A carbon nanotube cortical neuron with spike-timing-dependent plasticity.

This paper describes a carbon nanotube synapse circuit that exhibits Spike-Timing Dependant Plasticity (STDP). These synapses are found in cortical (e.g. pyramidal) neurons. Experiments with the synapse in a neuron circuit demonstrate changes in synaptic potential with pre- and post-spiking timing variations. The circuit design is biomimetic and changes in control voltages representing neurotransmitter concentration lead to changes in synaptic strength. The experiments are demonstrated with SPICE simulations using carbon nanotube transistor models.

Transarterial Chemoembolization of Metastatic Colorectal Carcinoma with Drug-Eluting Beads, Irinotecan (DEBIRI): Multi-Institutional Registry.

The purpose of this study was to evaluate the patient tolerance and efficacy of delivering locoregional chemotherapy to metastatic colorectal (MC) hepatic metastases via hepatic trans-arterial approach using irinotecan loaded drug eluting beads. This open-label, multi-center, single arm study included 30 MC patients, who had failed first line therapy. Of the 57 total embolization sessions, 12 (21% of sessions) were associated with adverse reactions during or after the treatment. After a median followup of 9 months, response rates by modified RECIST were 75% at 3 months and 66% at 6 months. Hepatic trans-arterial therapy using Irinotecan loaded DC Bead(TM) was safe and effective in the treatment of MCC as demonstrated by a minimal complication rate and acceptable tumor response.