F DiBianca | PubMed Health

PubMed1979

Digital radiograph of the chest using a computed tomography instrument.

Digital radiography (DR) was compared with conventional chest radiography in patients with mediastinal adenopathy, sarcoidosis, and metastatic adenocarcinoma. Contrast resolution was improved by the new technique, offering a wider latitude and edge enhancement. While small, low-contrast details were resolved best by conventional radiography, DR was superior for resolution of nodules. With further improvement of spatial and contrast resolution, DR could become the preferred technique of chest radiography.

Adenocarcinoma↗

PubMedDate not supplied

Quantitative digital fluorography. Computer vs. human estimation of vascular stenoses.

Digital subtracted images of iodinated rods, incorporating accurately measured areas of eccentric stenosis were obtained. The average subjective estimations of fractional area reduction (211 readings each) by three experienced angiographers were compared with values obtained using an interactive computer algorithm using the densitometric data. Results were analyzed to identify major influences on accuracy, including iodine concentration, vessel width, absolute severity of the stenosis, and vessel orientation. While no single factor appeared to seriously affect human accuracy, computer readings were significantly influenced by the tilt of the vessel in relation to the x-ray beam. Various potential sources of error including beam hardening, stenosis geometry, and scattering are discussed and appropriate algorithm corrections suggested. The importance of the availability of a reliable and accurate method to quantify vascular stenosis and volume of stenotic material is stressed.

Absorptiometry, Photon↗