HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Muehllehner, G. Articles by Stoub, E. W. Search for Related Content PubMed PubMed Citation Articles by Muehllehner, G. Articles by Stoub, E. W.

Correction for Field Nonuniformity in Scintillation Cameras Through Removal of Spatial Distortion

Searle Radiographics, Des Plaines, Illinois

Correspondence: For reprints contact: G. Muehllehner, PhD, Dept. of Radiology, Hospital of the Univ. of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104.

ABSTRACT

A method to correct for the spatial distortions of gamma cameras has been developed. The method consists of two parts: measuring spatial distortions and repositioning events during accumulation. Distortions are measured using a pattern consisting of parallel slits on 15-mm centers with slit-pattern images obtained in two orthogonal orientations. Slit locations are used to determine X and Y displacements. In repositioning camera events, X and Y event coordinates are digitized and correction displacements added. The procedure is implemented in hardware that repositions each event in real time without introducing additional dead time.

Distortion removal offers considerable advantage over other uniformity-improvement schemes, since it correctly compensates for the major cause of nonuniformity, spatial distortion. The method may be used for quantitative studies, because it does not change the number of detected events.

FOOTNOTES

^* Present address: Dept. of Radiology, Hospital of the Univ. of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104.