[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Anger Camera question

>Errors-To: <HobieS@concentric.net>
>References: <Pine.SOL.3.96.980403111554.18687A-100000@flop.ENGR.ORST.EDU>
>Date:         Fri, 3 Apr 1998 19:50:31 -0500
>Reply-To: Medical Physics Mailing List <MEDPHYS@LISTS.WAYNE.EDU>
>Sender: Medical Physics Listserver <medphys@lists.wayne.edu>
>From: Shackie <HobieS@CONCENTRIC.NET>
>Subject:      Re: Anger Camera question
>To: Multiple recipients of list MEDPHYS <MEDPHYS@LISTS.WAYNE.EDU>
>         ** Mail from Medphys Listserver **
>If you reply to this message, it will be posted on Medphys for all the
>subscribers to review ...
>With one crystal and many PM tubes, the light from a scintillation event fans
>out to many of the tubes near the event and all the tubes triangulate the
>event location based on how much light they detect. With many small cystals
>and a 1:1 tube / crystal ratio the resolution would depend on the crystal and
>tube size. The scintillation light would not cross the crystal interfaces.
>A multi-crystal design was used back in the 70's (by Baird I think) with
>light pipes between the crystal segments and the PM tubes to get the crystal
>size small enough for an acceptable (but very poor) resolution. The camera was
>by far the fastest gamma camera at the time and very useful for dynamic
>cardiac studies where the spacial resolution was adequate given the superior
>temporal resolution and sensitivity.
>Hobie Shackford
>Medical Physicist
>Roger Williams Medical Center
>Providence, RI
>Scott Crail wrote:
>>          ** Mail from Medphys Listserver **
>> If you reply to this message, it will be posted on Medphys for all the
>> subscribers to review ...
>> Could someone explain the advantage of using one large NAI crystal with
>> many photomultiplier tubes vs using many smaller NAI crystal (which should
>> be cheaper and more stable) and a one to one ratio for tubes to crystals
>> Scott Crail
>>  OSU
>> crail@engr.orst.edu