USA flag logo/image

An Official Website of the United States Government

Low Cost Co Doped Scintillator for Medical CT

Award Information

Department of Health and Human Services
Award ID:
Program Year/Program:
2006 / SBIR
Agency Tracking Number:
Solicitation Year:
Solicitation Topic Code:
Solicitation Number:
Small Business Information
44 HUNT ST WATERTOWN, MA 02472-4699
View profile »
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
Phase 1
Fiscal Year: 2006
Title: Low Cost Co Doped Scintillator for Medical CT
Agency: HHS
Contract: 1R43RR022921-01
Award Amount: $119,407.00


DESCRIPTION (provided by applicant): Although CsI:TI is one of the most desirable scintillators for a broad range of medical and industrial diagnostics, it has never been applicable to X-ray computerized tomography (CT). Despite the otherwise superb properties of CsI, it suffers from a persistent afterglow that simply does not decay fast enough to provide rapid framing rates without unacceptable carryover of the previous image. We have discovered that it is possible to suppress the afterglow of Csl:TI by as much as two orders of magnitude if a suitable modifier ion is inserted into the host lattice. The suppressive effect, however, is opti- mal for only short excitation pulses, and falls off sharply for extended exposures (> 6s) and radiation dose (>6R/s). characteristic of CT scans. Only one ion appears to retain this afterglow-suppressive capability under the conditions actually imposed during CT scans. We intend to investigate the effect of this ion on scintillation properties of Csl. The proposed Phase I research will primarily focus on growing codoped Csl:TI crystals with variations in composition to determine the range over which the maximum beneficial effects of reduced afterglow can be obtained without sacrificing the other excellent properties of the Csl:TI. These crystals will be subjected to extended exposures at high x-ray dose rates, and their scintillation properties will be evaluated before, during, and after such exposure. Changes in the afterglow and the emission efficiency will be measured to demonstrate the feasibility of our approach. For Phase I, we will seek to reduce the Csl:TI afterglow 2 ms after excitation to a level of 0.2% or lower, with an ultimate goal at least a factor of four below that. In addition, guided by the experimental results, we will seek both to understand the mechanisms responsible for the observed effect and to explore the possibility of enhancing it through the cooperative influence of an additional codopant. The success of this research will provide CT with the superior scintillation properties of Csl with low afterglow and at a cost far below scintillators now in use.

Principal Investigator:

Michael R. Squillante

Business Contact:

Gerald Entine
Small Business Information at Submission:

44 Hunt Street Watertown, MA 02472

EIN/Tax ID: 042546395
Number of Employees: N/A
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No