Demonstration of improved image resolution for larger focal spot sizes by decreasing anode angles in clinical settings

H. Nishankar; A. Shankar; S. V. Setlur Nagesh; D. Bednarek; S. Rudin

doi:10.1117/12.2512877

15 March 2019 Demonstration of improved image resolution for larger focal spot sizes by decreasing anode angles in clinical settings

H. Nishankar, A. Shankar, S. V. Setlur Nagesh, D. Bednarek, S. Rudin

Author Affiliations +

Proceedings Volume 10953, Medical Imaging 2019: Biomedical Applications in Molecular, Structural, and Functional Imaging; 109531J (2019) https://doi.org/10.1117/12.2512877
Event: SPIE Medical Imaging, 2019, San Diego, California, United States

Abstract

Image-guided neuro-endovascular interventional studies often require a high resolution image quality which requires the use of small focal-spot sizes. There is always a tradeoff while choosing focal-spot sizes. The use of small- focal-spots gives better spatial resolution but limits x-ray tube output and tube loading. The use of larger- focal-spots provides better heat dissipation capacity and higher x-ray output but gives rise to geometric blurring hence loss of spatial resolution. A method has been proposed which incorporates the use of the line-focus principle that can achieve a smaller projected focal-spot while keeping the actual focal-spot size as the medium focal-spot. Here the gantry is tilted to reduce the effective anode angle, hence the central axis is tilted producing a smaller projected focal-spot. This was tested by acquiring images of a Pipeline stent in the right jugular vein and a guidewire of a rabbit using a high-resolution CMOSbased fluoroscopic detector with 75um pixels. Also the gantry was tilted in the anode-cathode direction shifting the central axis to the anode side of the beam and the rabbit was aligned with the new perpendicular ray. Acquired images, for small focal-spot, medium focal-spot, and 7-degree tilted medium focal-spot were compared. While small focal-spot images demonstrated superior resolution, and both tilted and untilted medium focal spot images demonstrated lower noise due to the increased tube output the tilted medium focal spot images exhibited improved resolution. Line profiles and quantitative measures of generalized relative object detectability confirmed the advantage of the tilted medium focalspot method above all.

Citation Download Citation

H. Nishankar, A. Shankar, S. V. Setlur Nagesh, D. Bednarek, and S. Rudin "Demonstration of improved image resolution for larger focal spot sizes by decreasing anode angles in clinical settings", Proc. SPIE 10953, Medical Imaging 2019: Biomedical Applications in Molecular, Structural, and Functional Imaging, 109531J (15 March 2019); https://doi.org/10.1117/12.2512877

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

;

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
11 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Sensors

X-rays

Image resolution

Spatial resolution

Modulation transfer functions

CMOS sensors

Electron beams

Show All Keywords

Keywords/Phrases

Search In:

Publication Years