Ezio Maria Ferdeghini

Quantitative texture analysis in two-dimensional echocardiography : application to the diagnosis of myocardial amyloidosis.

Qualitative and subjective analysis of two-dimensional echocardiographic images of the myocardial wall allows one to identify amyloid heart disease; the quantitative analysis of regional image texture might be an accurate method to differentiate normal from amyloid myocardial structures. To test this hypothesis, two-dimensional echocardiograms of nine normal subjects and six patients with histologically documented amyloid heart disease were evaluated. Quantitative texture measurements of the first order (mean gray level, skewness, kurtosis, energy and entropy) overlapped between the two groups. Among the second order statistics variables, entropy was significantly and consistently higher in amyloid versus normal patient data (septum in parasternal long-axis view: 6.3 +/- 0.3 versus 5.9 +/- 0.4; septum in apical four chamber view: 6.2 +/- 0.2 versus 5.8 +/- 0.3). Therefore, amyloid-involved myocardial walls show ultrasound image texture alterations that may be quantified with digital image analysis techniques.

Two-dimensional echocardiography in myocardial amyloidosis.

Two‐dimensional echocardiography is the best means of identifying early cardiac amyloid infiltration and gauging its subsequent progression. The early asymptomatic phase is characterized on echocardiography by a mild‐to‐moderate increase in left ventricular and/or right ventricular wall thicknesses. The distinctive combination of low electrocardiography voltage and increase in left ventricular mass on the echocardiogram, both compatible with substantial amyloid infiltration, is valuable in diagnosis and appears to indicate the severity of the disease. Other ancillary but common findings are left atrial dilatation, a small pericardial effusion, thickening of cardiac valves, papillary muscles, and interatrial septum. Finally, there is a peculiar texture of myocardial walls, with highly refractile areas that are typical, although not specific, of myocardial amyloidosis and can also be quantitatively described by digital image analysis techniques. The echocardiography appearance of amyloidosis can closely mimic several other diseases. Asymmetric hypertrophy of the septum due to amyloid deposition may occur, simulating hypertrophic cardiomyopathy. The granular sparkling of myocardial walls is also found in myocarditis with severe fibrosis, and it is quite common in hypertrophic cardiomyopathy, as well as in other infiltrative diseases of the myocardium. It is not uncommon that the echocardiography examination represents a turning point in the work‐up of the patient, briskly orienting the clinician towards the correct diagnostic pathway. However, the likelihood of the car‐diologist‐echocardiographer to successfully and prospectively identify myocardial amyloidosis is substantially higher if all the clinical and electrocardiographic information is reviewed at the time of the echocardiographic examination. (ECHOCARDIOGRAPHY, Volume 8, March 1991)

Results of Vardenafil Mediated Power Doppler Ultrasound, Contrast Enhanced Ultrasound and Systematic Random Biopsies to Detect Prostate Cancer

PURPOSE We evaluated the ability of the phosphodiesterase-5 inhibitor vardenafil to increase prostate microcirculation during power Doppler ultrasound. We also evaluated the results of contrast and vardenafil enhanced targeted biopsies compared to those of standard 12-core random biopsies to detect cancer. MATERIALS AND METHODS Between May 2008 and January 2010, 150 consecutive patients with prostate specific antigen more than 4 ng/ml at first diagnosis with negative digital rectal examination and transrectal ultrasound, and no clinical history of prostatitis underwent contrast enhanced power Doppler ultrasound (bolus injection of 2.4 ml SonoVue® contrast agent), followed by vardenafil enhanced power Doppler ultrasound (1 hour after oral administration of vardenafil 20 mg). All patients underwent standard 12-core transrectal ultrasound guided random prostate biopsy plus 1 further sampling from each suspected hypervascular lesion detected by contrast and vardenafil enhanced power Doppler ultrasound. RESULTS Prostate cancer was detected in 44 patients (29.3%). Contrast and vardenafil enhanced power Doppler ultrasound detected suspicious, contrast enhanced and vardenafil enhanced areas in 112 (74.6%) and 110 patients (73.3%), and was diagnostic for cancer in 32 (28.5%) and 42 (38%), respectively. Analysis of standard technique, and contrast and vardenafil enhanced power Doppler ultrasound findings by biopsy core showed significantly higher detection using vardenafil vs contrast enhanced power Doppler ultrasound and standard technique (41.2% vs 22.7% and 8.1%, p <0.005 and <0.001, respectively). The detection rate of standard plus contrast or vardenafil enhanced power Doppler ultrasound was 10% and 11.7% (p not significant). CONCLUSIONS Vardenafil enhanced power Doppler ultrasound enables excellent visualization of the microvasculature associated with cancer and can improve the detection rate compared to contrast enhanced power Doppler ultrasound and the random technique.

A computer-aided diagnosis approach for emphysema recognition in chest radiography

The purpose of this work is twofold: (i) to develop a CAD system for the assessment of emphysema by digital chest radiography and (ii) to test it against CT imaging. The system is based on the analysis of the shape of lung silhouette as imaged in standard chest examination. Postero-anterior and lateral views are processed to extract the contours of the lung fields automatically. Subsequently, the shape of lung silhouettes is described by polyline approximation and the computed feature-set processed by a neural network to estimate the probability of emphysema. Images of radiographic studies from 225 patients were collected and properly annotated to build an experimental dataset named EMPH. Each patient had undergone a standard two-views chest radiography and CT for diagnostic purposes. In addition, the images (247) from JSRT dataset were used to evaluate lung segmentation in postero-anterior view. System performances were assessed by: (i) analyzing the quality of the automatic segmentation of the lung silhouette against manual tracing and (ii) measuring the capabilities of emphysema recognition. As to step i, on JSRT dataset, we obtained overlap percentage (Ω) 92.7±3.3%, Dice Similarity Coefficient (DSC) 95.5±3.7% and average contour distance (ACD) 1.73±0.87 mm. On EMPH dataset we had Ω=93.1±2.9%, DSC=96.1±3.5% and ACD=1.62±0.92 mm, for the postero-anterior view, while we had Ω=94.5±4.6%, DSC=91.0±6.3% and ACD=2.22±0.86 mm, for the lateral view. As to step ii, accuracy of emphysema recognition was 95.4%, with sensitivity and specificity 94.5% and 96.1% respectively. According to experimental results our system allows reliable and inexpensive recognition of emphysema on digital chest radiography.

Computer-aided recognition of emphysema on digital chest radiography

BACKGROUND Computed tomography (CT) is the benchmark for diagnosis emphysema, but is costly and imparts a substantial radiation burden to the patient. OBJECTIVE To develop a computer-aided procedure that allows recognition of emphysema on digital chest radiography by using simple descriptors of the lung shape. The procedure was tested against CT. METHODS Patients (N=225), who had undergone postero-anterior and lateral digital chest radiographs and CT for diagnostic purposes, were studied and divided in a derivation (N=118) and in a validation sample (N=107). CT images were scored for emphysema using the picture-grading method. Simple descriptors that measure the bending characteristics of the lung profile on chest radiography were automatically extracted from the derivation sample, and applied to train a neural network to assign a probability of emphysema between 0 and 1. The diagnostic performance of the procedure was described by the area under the receiver operating characteristic curve (AUC). RESULTS AUC was 0.985 (95% confidence interval, 0.965-0.998) in the derivation sample, and 0.975 (95% confidence interval, 0.936-0.998) in the validation sample. At a probability cutpoint of 0.55, the procedure yielded 92% sensitivity and 96% specificity in the derivation sample; 90% sensitivity and 97% specificity in the validation sample. False negatives on chest radiography had trace or mild emphysema on CT. CONCLUSIONS The computer-aided procedure is simple and inexpensive, and permits quick recognition of emphysema on digital chest radiographs.

Telematic integration of health data: a practicable contribution.

The patients’ clinical and healthcare data should virtually be available everywhere, both to provide a more efficient and effective medical approach to their pathologies, as well as to make public healthcare decision makers able to verify the efficacy and efficiency of the adopted healthcare processes. Unfortunately, customised solutions adopted by many local Health Information Systems in Italy make it difficult to share the stored data outside their own environment. In the last years, worldwide initiatives have aimed to overcome such sharing limitation. An important issue during the passage towards standardised, integrated information systems is the possible loss of previously collected data. The herein presented project realises a suitable architecture able to guarantee reliable, automatic, user-transparent storing and retrieval of information from both modern and legacy systems. The technical and management solutions provided by the project avoid data loss and overlapping, and allow data integration and organisation suitable for data-mining and data-warehousing analysis.

Assessment of normal testis growth by quantitative texture analysis of 2-D echo images

Six phases summarize the evolution of the healthy male gonad. Qualitative examination of two-dimensional echograms detects tonal differences at different ages of the testes. However, routine qualitative evaluation of the echograms is too subjective and dependent upon the scanner controls; on the other hand, simple morphology reports are not sufficient to establish the correct histologic and physiologic evolution. So far computer-assisted quantitative analysis of ultrasonic images has been successful in the characterization of tissues based on their echographic properties; thus this approach could be suitable for an accurate identification of the age of healthy testis. Sixty-two normal subjects, ranked in six groups according to age, underwent echographic examination in standard conditions. Echograms were digitized and analysed by means of well-established algorithms for first and second order statistics. Significant differences in tonal features were found able to discriminate among different ages, in agreement with the qualitative analysis and the histologic reports. Furthermore, some second order analysis features exhibit statistically significant alterations of the micro-structural organisation of the echo patterns consequent to changes of the configuration of the ultrasonic targets, that is, of the gonads histology. In conclusion, quantitative analysis of echograms can provide a tool for a better assessment of normal testis evolution than the qualitative approach.

Noninvasive quantitative assessment of segmental myocardial wall motion using technetium-99m 2-methoxy-isobutyl-isonitrile scintigraphy

Technetium-99m methoxy-isobutyl-isonitrile (MIBI) has been recently introduced to trace regional myocardial perfusion; the first-pass and the equilibrium-gated images have been also used to assess my

Computerized analysis of the transmural distribution of myocardial echo-contrast effect

The authors describe a method for the automatic analysis of the transmural distribution of the myocardial echo contrast effect. In anesthetized open-chest dogs the contrast agent SHU-454 was bolus-injected into the aortic root during short-axis 2-D echo, both at baseline and during coronary stenosis. End-diastolic echo images were digitized offline. In the first image of the sequence, the left-ventricular (LV) inner and outer myocardial edges were digitized. From the gravity center of the LV cavity a grid was automatically drawn to divide the myocardium into 16 equal sectors, and each sector into three layers. For each layer, the mean video density and the area were measured, sorted by sector and layer, and transferred online to a personal computer for further analysis. This system allows an automatic analysis of the distribution of the myocardial echo contrast effect, both in the space and in the time domain. Since the spatial distribution of the contrast effect parallels the distribution of coronary blood flow, this method might be a tool for studying the transmural distribution of coronary blood in vivo.<<ETX>>

Information systems for the management of clinical, administrative and government data of clinical imaging laboratories

From its first implementation, the integrated clinical and healthcare information system, developed at the CNR Clinical Physiology Institute, undergoes to updated and upgraded procedures and protocols, by solving problems of: harmonization of instrumentation of different brands; management of multimedial data provided by different medical imaging labs; satisfaction of both clinical and research needs as well as legal and economical requirements; user-friendship of the provided tools. Peculiar attention has been paid to the management of the laboratories devoted to biomedical imaging: medical and healthcare operators have coworked with engineers, to get a system able to guarantee coordinated activity, higher efficiency, simplified procedures, major concentration onto the medical decision-making issues, by supporting conventional techniques as well as new hybrid imaging technologies.