We use cookies to help you navigate efficiently and perform certain functions. You will find detailed information about all cookies under each consent category below.
The cookies that are categorised as "Necessary" are stored on your browser as they are essential for enabling the basic functionalities of the site. ...
Necessary cookies are required to enable the basic features of this site, such as providing secure log-in or adjusting your consent preferences. These cookies do not store any personally identifiable data.
Functional cookies help perform certain functionalities like sharing the content of the website on social media platforms, collecting feedback, and other third-party features.
Analytical cookies are used to understand how visitors interact with the website. These cookies help provide information on metrics such as the number of visitors, bounce rate, traffic source, etc.
Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors.
Advertisement cookies are used to provide visitors with customised advertisements based on the pages you visited previously and to analyze the effectiveness of the ad campaigns.
Rationale and Values for different body tissues and materials
- The chosen standards for the Hounsfield scale are universally available references and suited for computed axial tomography (CT).
- CT was developed for imaging the internal anatomy of living creatures, based on organised water structures.
- Values on the Hounsfield scale:
- CT scan window level set to -700 HU represents lung tissue.
- CT scan window level set to -1,000 HU represents air.
- CT scan window level set to 0 HU represents water.
- CT scan window level set to 60 HU represents liver tissue.
- Hounsfield Unit (HU) differentiation applies to medical-grade dual-energy CT scans, not cone beam computed tomography (CBCT) scans.
References
- 'Diagnostic radiology physics: a handbook for teachers and students' by International Atomic Energy Agency.
- 'Radiation oncology physics: a handbook for teachers and students' by International Atomic Energy Agency.
- 'AAPM Report No. 233: Performance Evaluation of Computed Tomography Systems - The Report of AAPM Task Group 233' by American Association of Physicists in Medicine.
- 'Cone-beam computerised tomography (CBCT) imaging of the oral and maxillofacial region: A systematic review of the literature' in the International Journal of Oral and Maxillofacial Surgery.
- 'Prostatic Diseases' by Herbert Lepor.
Applications
- Hounsfield Unit (HU) values can be used for the evaluation of tumors.
- A radiodensity of less than 10 HU in an adrenal tumor indicates a benign adrenal adenoma.
- Contrast agents can modify HU in some body parts, mainly blood.
- CT acquisition and reconstruction parameters can cause variations in HU values.
- CBCT scans provide unreliable HU readings.
External links
- Hounsfield unit
- Medcyclopaedia
- GE (Archived from the original on 2012-04-04)
- Hounsfield Unit - fpnotebook.com
- Introduction to CT physics (PDF) (Archived from the original (PDF) on 2007-09-26)
Hounsfield scale, Hounsfield unit, Medcyclopaedia, GE
- The Hounsfield scale measures radiodensity and represents tissue attenuation.
- The Hounsfield unit quantifies CT image pixel values and represents tissue density.
- Water has a value of 0 on the Hounsfield scale, air has a value of -1000, and bone has a value of +1000.
- Medcyclopaedia is an online medical encyclopedia that provides information on various medical topics, including the Hounsfield scale.
- GE is a global conglomerate involved in various industries, including healthcare, and offers CT scanners with advanced features.