A POSHE-Based Optimum Clip-Limit Contrast Enhancement Method for Ultrasonic Logging Images.

Enabled by piezoceramic transducers, ultrasonic logging images often suffer from low contrast and indistinct local details, which makes it difficult to analyze and interpret geologic features in the images. In this work, we propose a novel partially overlapped sub-block histogram-equalization (POSHE)-based optimum clip-limit contrast enhancement (POSHEOC) method to highlight the local details hidden in ultrasonic well logging images obtained through piezoceramic transducers. The proposed algorithm introduces the idea of contrast-limited enhancement to modify the cumulative distribution functions of the POSHE and build a new quality evaluation index considering the effects of the mean gradient and mean structural similarity.

Temporal Detection of Changes in the Vascularity and Concentration of Pigment Structures of a Skin Lesion.

Changes in morphology of a skin Iesion is indicative of melanoma, a deadly type of skin cancer. This paper proposes a temporal analysis approach to monitor the vascular appearance, the pigment structure, and growth of a skin Iesion. A set of digital images of a patients- skin Iesion acquired during follow-up imaging sessions serves as an input to our proposed system.

Detection of microcalcification with top-hat transform and the Gibbs random fields.

Breast cancer is one of the most common causes of death in women aged 40 and above. Early detection of breast cancer has been one of the prime topics of research in biomedical engineering area. Micro-calcifications (MCs) are the indicators of early stages of breast cancer, and the detection of these MCs will, in turn, lead to diagnosis and treatment of breast cancer at its earliest stages.

Influence of the severity of obstructive sleep apnea on nocturnal heart rate indices and its association with hypertension.

Objective: Both heart rate (HR) and blood pressure parameters provide important information on the pathophysiology of the cardiovascular regulatory mechanisms, and are mainly affected by the autonomic nervous system. We sought to clarify whether the severity of obstructive sleep apnea (OSA) affects nocturnal HRs and whether there is a relationship between nocturnal HRs and the presence of hypertension.

Methods: We retrospectively reviewed medical records of all patients who performed nocturnal polysomnography with monitoring of HRs, and examined whether there is a relationship among the nocturnal HRs, the severity of OSA and the presence of hypertension.

Influence of the right- versus left-sided sleeping position on the apnea-hypopnea index in patients with sleep apnea.

Purpose: Sleep and sleep position have a significant impact on physical, cardiac and mental health, and have been evaluated in numerous studies particularly in terms of lateral sleeping positions and their association with diseases. We retrospectively examined the relationship between the sleeping position and position-specific apnea-hypopnea index (AHI) in obstructive sleep apnea-hypopnea (OSA) patients.

Methods: We assessed the sleeping body position and the body position-specific AHI score in patients who were referred for suspected OSA and underwent diagnostic nocturnal polysomnography.

Chronic intermittent hypoxia caused by obstructive sleep apnea may play an important role in explaining the morbidity-mortality paradox of obesity.

Obesity has reached global pandemic that threatens the health of millions of people and is associated with numerous morbidities such as hypertension, type II diabetes mellitus, dyslipidemia, cor pulmonale, gallbladder disease, obstructive sleep apnea (OSA), certain cancers, osteoarthritis, increased surgical risk and postoperative complications, lower extremity venous and/or lymphatic problems, pulmonary embolism, stroke/cerebrovascular diseases and coronary arterial disease. Despite all these adverse associations, numerous studies and meta-analyses have documented an "obesity paradox" in which overweight and obese population with established cardiovascular disease have a better prognosis than do their lean counterparts. There are potential and plausible explanations offered by literature for these puzzling data; however, it still remains uncertain whether this phenomenon is attributable to a real protective effect of high body fat mass.

Upper airway detection and visualization from cone beam image slices.

This paper describes a method developed to assist in the detection and reconstruction of a three dimensional (3D) model of the human upper airway using cone beam computed tomography (CBCT) image slices and a 3D Gaussian smoothing kernel. The segmented and reconstructed volumetric airway is characterized by the corresponding three principal axes that are selected for viewing direction orientation via rotation and translation. These axes are derived using the 3D Principal Component Analysis (PCA) result of the rendered volume.

Documentation of impaired coronary blood flow in chronic obstructive pulmonary disease patients.

Background: In the current study, the effects of moderate to severe chronic obstructive pulmonary disease (COPD) on coronary blood flow in patients with angiographically proven normal coronary arteries was evaluated.

Methods And Results: A total of 85 patients with moderate to severe COPD and 39 age- and sex-matched control partcipants, who underwent diagnostic coronary angiography and found to have normal epicardial coronary angiogram constituted the COPD and control groups, respectively. The 2 groups were compared for Thrombolysis In Myocardial Infarction (TIMI) frame counts in each major coronary artery.

Myocardial noncompaction presenting with Brucella endocarditis.

Noncompaction of ventricular myocardium is a unique congenital cardiomyopathy with its own clinical presentation and course. It is more frequently associated with complications of congestive heart failure, thromboembolism and malignant ventricular arrhythmias; however, concomitance of valvular pathologies or infective endocarditis with noncompaction of ventricular myocardium has seldom been reported. We describe herein the first case of left ventricular myocardial noncompaction presenting with Brucella endocarditis with aortic and mitral valve involvements, whom subsequently underwent successful medical and surgical treatment.

Topographic modeling of cellular images.

Modeling the three-dimensional (3D) microscopic cellular images analytically is rather a difficult task due to their random shapes and deformable characteristics. One remedy is to use the topographic structures to approximate the sample surfaces and produce the unknown molecular structures by means of deformable shape generation methods from the topographic models. Here, a training sample set of 3D images is collected for shape discrimination.

Hemodynamic change in transmitral gradient during Valsalva maneuver and its relation with left atrial function, functional capacity, and pulmonary artery pressure in patients with mitral stenosis in sinus rhythm.

Background: The hemodynamic factors contributing to the clinical symptomatology in patients with mitral stenosis (MS) have been under investigation. The objective of this study was to evaluate the use of the Valsalva maneuver in patients with MS and whether there is an association between the degree of the hemodynamic changes in transmitral gradient (TG) in response to Valsalva maneuver and functional status, systolic pulmonary artery pressure, and left atrial function in patients with MS in sinus rhythm.

Methods: The study prospectively evaluated 42 patients (37 female, mean age 40 +/- 10 years) with a diagnosis of pure MS in sinus rhythm.

A case of pulmonary alveolar microlithiasis with cardiac constriction secondary to severe adjacent pleural involvement.

Pulmonary alveolar microlithiasis (PAM) is a rare disorder of uncertain etiology and pathogenesis that is characterized by tiny calcium phosphate depositions in lung alveoli. Ectopic organ involvement has been reported infrequently. We hereby present a patient with PAM complicated by severe pleural calcification that has caused a constrictive cardiac physiology, a heretofore unknown occurrence/association.

Exercise-induced ventricular tachycardia associated with J point ST-segment elevation in inferior leads in a patient without apparent heart disease: a variant form of Brugada syndrome?

Exercise-induced monomorphic ventricular tachycardia originating in the right ventricular outflow tract without evidence of structural heart disease can be idiopathic or can be the harbinger of structural abnormalities such as arrhythmogenic right ventricular dysplasia. Recently, the so-called variant Brugada syndrome has been reported in very few cases in the literature and is much less electrophysiologically defined in terms of its clinical significance. We present the case of a 21-year-old man with exercise-induced monomorphic ventricular tachycardia (left bundle-branch block/right axis deviation), without detectable structural heart disease, with evidence of J point and ST-segment elevation in electrocardiogram leads II, III, and aVF after intravenous administration of propafenone.

Left atrial compression by thoracic aneurysm mimicking congestive heart failure.

Most patients with thoracoabdominal aortic aneurysm are asymptomatic and this aneurysm has rarely been reported as a cause of congestive heart failure. We present an infrequent case of extrinsic left atrial compression caused by a descending thoracic aneurysm diagnosed by transthoracic echocardiography as a cause of heart failure.