Cone-beam CT
Updates to Article Attributes
Cone beam CT (CBCT) is a variant type of computed tomography (CT), and is used particularly in dental and extremity imaging but has recently found new application in dedicated breast imaging 4,5. It differs from conventional CT in that it uses a cone-shaped x-ray beam and two dimensional detectors instead of a fan-shaped x-ray beam and one dimensional detectors.
Physics
In cone beam-beam CT, a divergent cone-shaped source of radiation is directed through the target. The attenuated x-rays are detected on the opposite side by an x-ray detector, which has multiple dexels in the x and y-axis 2. Volume acquisition can thus be acquired with fewer rotations of the x-ray tube gantry. This differs from fan-beam CT, which uses a 2D fan-shaped x-ray beam in helical progression to acquire image data. Furthermore, fan-beam CT detector only has dexels in the x-axis.
The advent of cone beam-beam CT has brought about several advantages over its fan-beam counterpart, but it also has its inherent disadvantages.
Advantages
- decreased examination time
- decreased patient movement artifact
- increased x-ray tube efficiency 3
Disadvantages
- increased scattered radiation
- potential for cone
beam-beam artifact if an inappropriate reconstruction algorithm is used
Indications
Dental imaging
Cone beam CT is used to investigate the exact location of jaw pathologies such as tumours, inflammatory lesions, exact location of impacted teeth before oral or maxillofacial surgery 6.
It is also used in endodontics, implant dentistry, orthodontics, peridontics, temporomandibular joint imaging, and forensic dentistry 6.
Breast imaging
The three dimensional-dimensional cone beam CT aims to address the limitation of two-dimensional imaging on mammography with high contrast between pathological and normal breast tissues, and reducingreduce the overlap of breast lesions from surrounding breast parenchyma 4.
Cancer treatment
After transcatheter arterial chemoembolisation of hepatocellular carcinoma, CBCTcone beam CT is done to assess the amount of drug retained within the tumour 7.
-<p><strong>Cone beam CT (CBCT)</strong> is a variant type of <a href="/articles/computed-tomography">computed tomography (CT)</a>, and is used particularly in dental and extremity imaging but has recently found new application in dedicated breast imaging <sup>4,5</sup>. It differs from conventional CT in that it uses a cone-shaped x-ray beam and two dimensional detectors instead of a fan-shaped x-ray beam and one dimensional detectors. </p><h4>Physics</h4><p>In cone beam CT, a divergent cone-shaped source of radiation is directed through the target. The attenuated x-rays are detected on the opposite side by an x-ray detector, which has multiple <a href="/articles/dexel">dexels</a> in the x and y-axis <sup>2</sup>. Volume acquisition can thus be acquired with fewer rotations of the x-ray tube gantry. This differs from fan-beam CT, which uses a 2D fan-shaped x-ray beam in helical progression to acquire image data. Furthermore, fan-beam CT detector only has dexels in the x-axis.</p><p>The advent of cone beam CT has brought about several advantages over its fan-beam counterpart, but it also has its inherent disadvantages. </p><h6>Advantages</h6><ul>- +<p><strong>Cone beam CT (CBCT)</strong> is a variant type of <a href="/articles/computed-tomography">computed tomography (CT)</a>, and is used particularly in dental and extremity imaging but has recently found new application in dedicated breast imaging <sup>4,5</sup>. It differs from conventional CT in that it uses a cone-shaped x-ray beam and two dimensional detectors instead of a fan-shaped x-ray beam and one dimensional detectors. </p><h4>Physics</h4><p>In cone-beam CT, a divergent cone-shaped source of radiation is directed through the target. The attenuated x-rays are detected on the opposite side by an x-ray detector, which has multiple <a href="/articles/dexel">dexels</a> in the x and y-axis <sup>2</sup>. Volume acquisition can thus be acquired with fewer rotations of the x-ray tube gantry. This differs from fan-beam CT, which uses a 2D fan-shaped x-ray beam in helical progression to acquire image data. Furthermore, fan-beam CT detector only has dexels in the x-axis.</p><p>The advent of cone-beam CT has brought about several advantages over its fan-beam counterpart, but it also has its inherent disadvantages. </p><h6>Advantages</h6><ul>
-<li>potential for cone beam artifact if an inappropriate reconstruction algorithm is used</li>-</ul><h4>Indications</h4><h5>Dental imaging</h5><p>Cone beam CT is used to investigate the exact location of jaw pathologies such as tumours, inflammatory lesions, exact location of impacted teeth before oral or maxillofacial surgery <sup>6</sup>. </p><p>It is also used in endodontics, implant dentistry, orthodontics, peridontics, temporomandibular joint imaging, and forensic dentistry <sup>6</sup>.</p><h5>Breast imaging</h5><p>The three dimensional cone beam CT aims to address the limitation of two-dimensional imaging on mammography with high contrast between pathological and normal breast tissues, and reducing the overlap of breast lesions from surrounding breast parenchyma <sup>4</sup>.</p><h5>Cancer treatment</h5><p>After <a href="/articles/transcatheter-arterial-chemoembolisation">transcatheter arterial chemoembolisation</a> of <a href="/articles/hepatocellular-carcinoma">hepatocellular carcinoma</a>, CBCT is done to assess the amount of drug retained within the tumour <sup>7</sup>.</p><p> </p>- +<li>potential for cone-beam artifact if an inappropriate reconstruction algorithm is used</li>
- +</ul><h4>Indications</h4><h5>Dental imaging</h5><p>Cone beam CT is used to investigate the exact location of jaw pathologies such as tumours, inflammatory lesions, exact location of impacted teeth before oral or maxillofacial surgery <sup>6</sup>. </p><p>It is also used in endodontics, implant dentistry, orthodontics, peridontics, temporomandibular joint imaging, and forensic dentistry <sup>6</sup>.</p><h5>Breast imaging</h5><p>The three-dimensional cone beam CT aims to address the limitation of two-dimensional imaging on mammography with high contrast between pathological and normal breast tissues and reduce the overlap of breast lesions from surrounding breast parenchyma <sup>4</sup>.</p><h5>Cancer treatment</h5><p>After <a href="/articles/transcatheter-arterial-chemoembolisation">transcatheter arterial chemoembolisation</a> of <a href="/articles/hepatocellular-carcinoma">hepatocellular carcinoma</a>, cone beam CT is done to assess the amount of drug retained within the tumour <sup>7</sup>.</p><p> </p>
Unable to process the form. Check for errors and try again.