[Oradlist] CBCT artifact?

[plachtovics márk]

Dear Bruno Correa de Azevedo, we had the same problem while the assistant forget the remove of the chin holder and the head holder before the calibration process (please se the attachment). After the remove both holder we repeated the calibration process, and it was ok. Best regards Mark Plachtovicsoral surgeonHungary, Budapest

"Andrés Briner" <andresbriner at gmail.com> írta:
> If no foreign objects are inside the FOV, this artifact could be produced by a malfunction of a pixel or a group of pixels in the sensor surface.    Normally a sensor has a number of no more of 3 bad pixels that could be acceptable at the moment of manufacture of the CBCT machine, those pixels are ignored by software in order not to affect the images, but when pixel malfunction arises during the use period of this sensor it affects the image with this circular artifact.   There are two ways to fix the problem.   1.-  To replace the sensor (normally very expensive)    2.-  To ask the manufacturer to make the software to ignore the bad pixel (Cheap or no cost).   Dr. Andres BrinerImax Radiological centersSantiago Chile
>  
> On Thu, Apr 1, 2010 at 3:07 AM, mohamed saeed <nawa2222 at yahoo.com> wrote:


>>we have similar artifact in our machine and i think the cause of that is the inhomogeneity of the ccd pixel efficiency.  Mohamed Saeed Omar, DDSChief radilogic technologistKing Saud University
>>Riyadh, Saudi Arabianawa2222 at yahoo.com
>>
>>--- On Wed, 3/31/10, Bruno Azevedo <brunozvd at yahoo.com> wrote:

>>>
>>>From: Bruno Azevedo <brunozvd at yahoo.com>
>>>Subject: [Oradlist] CBCT artifact?
>>>To: "Oral lists" <oradlist at lists.ucla.edu>
>>>Date: Wednesday, March 31, 2010, 9:20 PM 
>>>
>>> Has anyone seem this type of image before?Bruno.
>>> Bruno Correa de Azevedo DDS MS 
>>>
>>>Assistant Professor Oral and Maxillofacial Radiology
>>>
>>>College of Dental Medicine Western University of Health Sciences
>>>
>>>309 E. Second St.
>>>
>>>Pomona, California 91766
>>>
>>>909-706-3504 -----Inline Attachment Follows-----
>>>
>>>_______________________________________________
>>>Oradlist mailing list
>>>Oradlist at lists.ucla.edu
>>>http://lists.ucla.edu/cgi-bin/mailman/listinfo/oradlist

>>
>>
>>
>>_______________________________________________
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>> 

>
> 
>If no foreign objects are inside the FOV, this artifact could be produced by a malfunction of a pixel or a group of pixels in the sensor surface.    Normally a sensor has a number of no more of 3 bad pixels that could be acceptable at the moment of manufacture of the CBCT machine, those pixels are ignored by software in order not to affect the images, but when pixel malfunction arises during the use period of this sensor it affects the image with this circular artifact.   There are two ways to fix the problem.   1.-  To replace the sensor (normally very expensive)    2.-  To ask the manufacturer to make the software to ignore the bad pixel (Cheap or no cost).  
>
> 
>Dr. Andres Briner
>Imax Radiological centers
>Santiago 
>Chile
> 
> 
> 
>On Thu, Apr 1, 2010 at 3:07 AM, mohamed saeed nawa2222 at yahoo.com> wrote:
>
>
>
>
>
>we have similar artifact in our machine and i think the cause of that is the inhomogeneity of the ccd pixel efficiency.
> 
> 
>Mohamed Saeed Omar, DDS
>Chief radilogic technologist
>King Saud UniversityRiyadh, Saudi Arabia
>nawa2222 at yahoo.com
>--- On Wed, 3/31/10, Bruno Azevedo brunozvd at yahoo.com> wrote:
>From: Bruno Azevedo brunozvd at yahoo.com>Subject: [Oradlist] CBCT artifact?
>To: &quot;Oral lists&quot; oradlist at lists.ucla.edu>Date: Wednesday, March 31, 2010, 9:20 PM 
>
>
>
>
>
>
>Has anyone seem this type of image before?
>Bruno. Bruno Correa de Azevedo DDS MS 
>
>Assistant Professor Oral and Maxillofacial Radiology
>College of Dental Medicine Western University of Health Sciences
>309 E. Second St.
>Pomona, California 91766
>909-706-3504 
>-----Inline Attachment Follows----- 
>
>_______________________________________________Oradlist mailing listOradlist at lists.ucla.eduhttp://lists.ucla.edu/cgi-bin/mailman/listinfo/oradlist
>_______________________________________________Oradlist mailing listOradlist at lists.ucla.eduhttp://lists.ucla.edu/cgi-bin/mailman/listinfo/oradlist
>
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