Computer-Assisted Detection of Pulmonary Nodules: Preliminary Observations Using a Prototype System with Multidetector-Row CT Data Sets

The continued revolution in multidetector-row CT (MDCT) scanning increases the quality of lung imaging but at the cost of a greater burden of data for review and interpretation. This article discusses our preliminary experience with prototype software for lung nodule detection and characterization using MDCT data sets. We discuss the potential role of computer-assisted detection (CAD) as applied to the automatic detection of lung nodules. We also review the process of CAD, outline its potential results, and explore how it may fit into existing radiology practice. Finally, we discuss MDCT data-acquisition parameters and how they may affect the performance of CAD.     

Nuclear medicine Competitors or collaborators?

Here in the USA

Nuclear medicine Competitors or collaborators?     

Neuromuscular transmission failure due to common krait (Bungarus caeruleus) envenomation

Neurophysiological studies were performed in 12 patients with neuromuscular paralysis due to envenomation by the common krait (Bungarus caeruleus). All patients presented with an acute, reversible, oculofaciobulbar paresis. In addition, 7 patients had weakness of the limb muscles and 4 required assisted mechanical ventilation. Neurophysiological abnormalities included: (1) a reduction in the amplitude of the median-elicited compound muscle action potential (CMAP) in 4 patients; and (2) a decremental response (>10%) to 3-Hz repetitive nerve stimulation (RNS) in 4 patients. With 1 exception, these abnormalities were noted only in clinically weak muscles. The administration of edrophonium to 6 patients produced an insignificant increase in CMAP amplitudes as well as partial (not significant) improvement in the decremental response to 3-Hz RNS. Neurophysiological studies were performed in 2 patients before and after the administration of 20 mL of polyvalent antivenom. A decrease in amplitude of the median-elicited CMAP amplitude occurred after the administration of antivenom. In 1 patient, administered 100 mL of antivenom, the median-elicited CMAP amplitude increased and the decrement to 3-Hz RNS decreased. Neurophysiological studies can provide useful information regarding the nature, severity, and therapy of the neuroparalytic syndrome of krait envenomation.     

Live/Real Time Three‐Dimensional Transesophageal Echocardiographic Findings in Caseous Mitral Annular Calcification

We describe a 77‐year‐old female with hypertrophic cardiomyopathy in whom live/real time three‐dimensional transesophageal echocardiography (3DTEE) provided incremental value over two‐dimensional transthoracic and transesophageal echocardiography (2DTTE, 2DTEE) and three‐dimensional transthoracic echocardiography (3DTTE) in making a more comprehensive assessment and a more confident diagnosis of caseous mitral annular calcification. 3DTEE revealed a portion of the mass to consist of small, multiple, highly echogenic discrete band‐like and punctate areas within a relatively much less echogenic stroma and surrounded by a well defined highly echogenic border. This appearance correlated with the pathological findings of calcific granules/strands located in a liquefied or semiliquefied interior providing a typical toothpaste like appearance. The highly echogenic outer border represented the residual outer portion or rim of the calcific mass which did not undergo liquefaction. These findings on 3DTEE which correlated with the toothpaste like appearance seen at surgery were not visualized on 2DTTE, 2DTEE, and 3DTTE. (Echocardiography 2010;27:1147‐1150)     

Recent advances in fibroblast signaling and biology in scleroderma

PURPOSE OF REVIEW: Systemic sclerosis is a complex disease manifesting itself by fibrosis of skin and other internal organs. Fibroblasts isolated from scleroderma lesions and cultured in vitro are characterized by increased synthesis of collagen and other extracellular matrix proteins, consistent with the disease phenotype. Cultured systemic sclerosis fibroblasts therefore serve as a principal experimental model for studying the molecular and cellular mechanisms involved in collagen overproduction in this disease. This review will discuss recent findings related to intracellular signal transduction pathways implicated in deregulated extracellular matrix deposition by systemic sclerosis fibroblasts. RECENT FINDINGS: Recent findings suggest that constitutively elevated synthesis of extracellular matrix by cultured systemic sclerosis fibroblasts is, at least in part, due to the aberrant activation of the autocrine transforming growth factor-beta signaling. Enhanced constitutive transforming growth factor-beta signaling may result from the elevated levels of transforming growth factor-beta receptor type I and/or inappropriate activation of Smad3. These alterations of the transforming growth factor-beta signaling in systemic sclerosis fibroblasts may facilitate increased collagen production in vivo even under conditions of low ligand availability. However, there exist many inconsistencies among published reports regarding the detailed mechanisms of this pathway in systemic sclerosis fibroblasts, and additional studies in this area are needed. Other signaling molecules implicated in fibrotic phenotype include several members of the protein kinase C family, mammalian target of rapamycin, mitogen-activated protein kinase, necdin, reactive oxygen species, and sphingolipids. These signaling pathways may work in conjunction with transforming growth factor-beta signaling to regulate the behavior of systemic sclerosis fibroblasts. SUMMARY: Alterations in multiple signaling pathways contribute to elevated extracellular matrix synthesis by systemic sclerosis fibroblasts. Improved understanding of the key signaling molecules may provide a novel avenue for therapeutic interventions.     

Syncope in a middle aged male due to acute rheumatic fever

Rheumatic fever is a multi system disease which occurs following infection with group A beta hemolytic streptococcus. It is commonest in the age group of 5-15 years but can occur in adults also. First degree atrioventricular block is a common manifestation of acute rheumatic fever and is included in the Jones criteria but Wenckebacks phenomena and complete heart block are relatively rare manifestations of rheumatic fever. Syncope occurring in acute rheumatic fever is also infrequently reported. We report the case of a 38-year-old male with rheumatic carditis who had advanced atrioventricular block which resulted in syncope and required a temporary pacemaker insertion.     

Prevalence of abdominal wall hernia in participants with abdominal aortic aneurysm versus peripheral arterial disease--a population-based study

Small studies suggest an association between abdominal aortic aneurysms (AAAs) and hernias, possibly related to connective tissue weakness. We evaluated the association between AAA and abdominal wall hernia (AWH), using peripheral arterial disease (PAD) patients as controls, in Olmsted County, Minnesota. In a retrospective cohort study we queried the electronic medical records for the diagnosis of AAA. The resulting data were then queried for prevalence of AWH. The same set of queries was repeated for PAD. Occurrence of AWH in the 2 groups was compared using the chi-square test. Of the 187 151 patient records queried, 939 had AAA and 3465 had PAD. Abdominal wall hernia occurred in 157 (16.7%) patients with AAA and in 343 (9.9%) patients with PAD. Abdominal wall hernia was 1.7 times more prevalent in those with AAA versus PAD (P < .0001). A history of hernia may prompt screening for AAA in some patients.     

Circulatory and hepatic failure at admission predicts mortality of severe scrub typhus patients: A prospective cohort study

Objective: To study the spectrum and outcome of severe scrub typhus in adult patients and to predict the hospital mortality by organ failure on admission.Methods: This was a prospective observational cohort study conducted between July 2017 and October 2020 at the medical emergency centre of PGIMER, Chandigarh, India. One hundred and twenty-six patients aged ≥13 years were diagnosed with scrub typhus. Severe disease was defined as the presence of organ failure based on the Sequential Organ Failure Assessment(SOFA) score on admission.Results: About two-thirds of the patients were from geographic regions outside the endemic sub-Himalayan belt. Fever(99.21%) and dyspnea(79.36%) were the most frequent complaints. Respiratory failure(81.75%) was the most common organ failure, followed by hepatic(52.38%), coagulative(47.62%), circulatory(33.33%), renal(21.43%), and cerebral dysfunction(13.49%). The median(Q1, Q3) SOFA score was 8(6, 9), and 48.41% of the patients had a quick-SOFA score ≥2. Organ supports with invasive ventilation(40.48%), vasopressors(36.51%), and renal replacement therapy(7.14%) were frequently required. The in-hospital mortality was 11.90% and was independently predicted by circulatory and hepatic failures on multivariate logistic regression(OR 11.12, 95% CI 1.73-71.31 and OR 8.49, 95% CI 1.18-61.41, respectively).Conclusions: Most patients had pulmonary dysfunction; circulatory or hepatic failure on admission strongly predicts death.