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Computed tomography (CT) is a medical imaging method employing tomography created by computer processing. Digital geometry processing is used to generate a three-dimensional image of the inside of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation. CT produces a volume of data which can be manipulated, through a process known as "windowing", in order to demonstrate various bodily structures based on their ability to block the X-ray beam. Although historically the images generated were in the axial or transverse plane, orthogonal to the long axis of the body, modern scanners allow this volume of data to be reformatted in various planes or even as volumetric (3D) representations of structures. Although most common in medicine, CT is also used in other fields, such as nondestructive materials testing. Another example is archaeological uses such as imaging the contents of sarcophagi or the DigiMorph project at the University of Texas at Austin which uses a CT scanner to study biological and paleontological specimens. Usage of CT has increased dramatically over the last two decades. An estimated 72 million scans were performed in the United States in 2007. From Wikipedia under the
GNU Free Documentation License Why does the CT scan detect different shades? Q. If the CT scan emits X-rays, why are there different shades in the image since X-ray can penetrate through everything expect bone? Why isn't the CT scan another X-ray machine? What sets them apart as to their energy modalities. Asked by Fan G - Mon Oct 29 18:20:23 2007 - - 5 Answers - 0 Comments A. A CT scanner IS an x-ray machine. It just uses and detects x-rays in a different manner than plain films. There are different shades because different types of tissues interact with x-rays differently. These differences can be detected and displayed as different shades on the computer. BTW, to be completely correct, x-rays can penetrate through bone. Answered by dwp_hornblower - Mon Oct 29 20:50:50 2007 Can a CT scan tell if a meningioma is benign? Q. I recently had a CT scan (headaches) and my neurologist said I have 2 small benign meningiomas in my right frontal lobe. How can he look just at the scan and tell they are benign without running any kind of tests? Is that possible? Asked by mommy2karys - Fri Jun 22 12:18:30 2007 - - 2 Answers - 0 Comments A. I was diagnosed with a golf ball sized tuberculum sellae meningioma 3 years ago and had surgery 2 weeks after diagnosis. All of my tumor was removed and I have had no regrowth. The only way to know for sure the grade (benign or malignant) of any tumor, or to even identify the type of tumor definitely is by running pathology tests on the tumor tissue, which can only be done after surgical removal of all or part of the tumor. A CT scan or MRI can give a "probable" diagnosis. My CT scan was read by one radiologist who diagnosed my "lesion" as an aneurysm. I had the same CT scan read by another radiologist who said it was a "probable meningioma". I then had an MRI done and had a more precise diagnosis of a meningioma, but still it was… [cont.] Answered by Schwinn - Fri Jun 22 14:08:08 2007 Can a CT scan or MRI show serotonin depletion or other neurochemical problems?
Q. Can CT scans or MRI's or other brain scans (please list) show neurochemical problems with the brain such as low serotonin, receptor damage, low/high dopamine, problem with HPA axis, ACTH, etc?? What is the best brain test? MRI or CT scan ? are there other ones which are better? Asked by Dj Conquest - Wed Aug 13 22:58:01 2008 - - 1 Answers - 0 Comments A. Specialized PET scans can be done to look at specific brain chemistry-- where a particular drug works in the brain, etc. MR spectroscopy can identify specific chemicals in the brain. THis is usually used looking for tumor markers- helps distinguish one kind of tumor from another. I do not think they can run a "general unknown" kind of scan to detect levels of all the many many chemicals in the brain. There are so many neurotransmitters now they just number them. Maybe there is a Researcher on YA who has more recent information. Things change so fast, it is hard to keep up. Answered by aneurodoc125 - Thu Aug 14 00:49:39 2008 From Yahoo Answer Search: "ct scan"  healthline.com Wed, 20 Jan 2010 09:22:29 PST A new study looks at the amount of radiation patients are exposed to while undergoing imaging tests, CT scans.. healthline.com.  ct.gov Tue, 30 Jun 2009 11:46:57 PDT Vote EZ CT Optical Scan Machines Abstract: View Demonstration (English)View Demonstration (Spanish) An easy and secure way to vote. Connecticut ... ct.gov.  current.com Thu, 29 Jul 2010 00:07:30 PDT Source: HealthDay Related MedlinePlus Topics: CT Scans , Diagnostic Imaging , Nuclear Scans ... CT Scans Diagnostic Imaging Medical Imaging ... current.com. From Google Video Search: "ct scan"  mlb.mlb.com Tue, 03 Aug 2010 05:59:32 GMT+00:00 after beaning MLB.com Outfielder Carlos Gomez was struck in the head by a pitch in the eighth inning and taken to the hospital for a CT scan , according to manager Ken Macha. ... Brewers Round 'em Up: Tuesday 08.03.10 Milwaukee Journal Sentinel (blog) Crew posts 26 hits, 18 runs in rout of Cubs MLB.com Narveson leads Brewers past Cubs The Associated Press CBS2 Chicago  ksax.com Mon, 23 Aug 2010 14:33:27 GMT+00:00 ksax with plans for Kristin to go to college in Milwaukee, doctors recommended she have a CT scan of her upper and lower abdomen in May of this year. ...  nbcsports.msnbc.com Wed, 04 Aug 2010 01:15:38 GMT+00:00 msnbc.com It would be fair to expect him to undergo a full evaluation, including a CT scan . We'll update his status when it is made available by the team. From Google News Search: "ct scan" From Yahoo Image Search: "ct scan"  9999articles.com Brent Thompson Sat, 04 Sep 2010 08:32:36 GM Typically the imaging scan which involves the magnetic resonance image or the . CT scan. is needed to know the exact location and extent of the mesothelioma cancer. There are also various mesothelioma cancer treatments available when the ... From Google Blog Search: "ct scan" |
