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Fundamental physics of magnetic resonance imaging.

• Theodore Villafana
• Radiologic clinics of North America
• 1988

Although similar to computerized tomography, in that cross-sectional images are produced, the physical principles underlying magnetic resonance are entirely different. The MRI process, as commonly… (More)

Temporal response of microdensitometers.

• Theodore Villafana
• Medical physics
• 1978

Microdensitometers have both spatial and temporal finite responses which may lead to degradation in images being analyzed. These responses may be quantitated in terms of spatial and temporal… (More)

Modulation transfer function of a finite scanning microdensitometer slit.

• Theodore Villafana
• Medical physics
• 1975

Inherent in the line-spread function approach in modulation transfer function (MTF) determinations is the use of a microdensitometer to scan the density pattern resulting from the line exposure. In… (More)

Effect of finite exposure slits in determination of the line spread function and modulation transfer function.

• Theodore Villafana
• Acta radiologica: therapy, physics, biology
• 1977

The modulation transfer function of radiologic imaging systems is commonly obtained by determining the line spread function (LSF) of the system and computing its Fourier transform. Ideally, LSF… (More)

Technologic advances in computed tomography.

• Theodore Villafana
• Current opinion in radiology
• 1991

Technologic improvements in CT continue. As always, emphasis in the past year has been on reducing scan times. Units employing slip-ring technology are now available. This technology makes possible… (More)

Testing of Computed Tomography Scanners

• P H P Lin, Thomas J. Beck, +12 authors Raymond P. Rossi
• 1993

DISCLAIMER: This publication is based on sources and information believed to be reliable, but the AAPM and the editors disclaim any warranty or liability based on or relating to the contents of this… (More)

Generators, x-ray tubes, and exposure geometry in mammography.

• Theodore Villafana
• Radiographics : a review publication of the…
• 1990

The author reviews different types of generators used in mammography, x-ray tubes, and physical principles affecting exposure geometry. Target and filter combinations, focal spots, and unsharpness… (More)

Interpretation of measured exposure rate levels in diagnostic radiology.

• Theodore Villafana
• Health physics
• 1981

Effect of microdensitometer scan slit misalignment in MTF determinations.

• Theodore Villafana
• Medical physics
• 1975

To determine the modulation transfer function (MTF) of a radiographic film or film-screen system, it is common to expose the system to a line source and scan the result with a microdensitometer. The… (More)

Basic science curriculums in nuclear cardiology and cardiovascular imaging: evolving and emerging concepts.

• William A Van Decker, Theodore Villafana
• Journal of nuclear cardiology : official…
• 2008

The teaching of basic science with regard to physics, instrumentation, and radiation safety has been part of nuclear cardiology training since its inception. Although there are clear educational and… (More)

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