Computer-aided simple triage explained

Computer-aided simple triage
Purpose:computer systems that assist in initial interpretation of image

Computer-aided simple triage (CAST) are computerized methods or systems that assist physicians in initial interpretation and classification of medical images. CAST is a sub-class of computer-aided diagnosis (CAD). CAST software systems perform a fully automatic initial triage (classification) of diagnostic medical imaging studies. CAST is primarily intended for emergency diagnostic imaging, where a prompt diagnosis of critical, life-threatening condition is required.[1]

Overview

Computer-aided simple triage (CAST) is a combination of computer-aided diagnosis (CAD) and simple triage and rapid treatment (START).CAST performs a fully automatic initial interpretation of a study – a "wet read". Studies are automatically classified into some meaningful categories, e.g. positive/negative, critical/minor/normal, difficult/simple/non-diagnostic, etc.

CAST is primarily intended for emergency diagnostic imaging. Unlike traditional CAD, mainly used to detect malignant lesions, CAST deals with acute, life-threatening conditions, when a prompt diagnosis is timecritical. While the primary goal of the traditional CAD is improving the diagnostic accuracy of a human reader, the CAST addresses two other problems:

Use case scenario

As with the traditional CAD, CAST does not substitute the physician. It only alerts about the possibility of acute, critical condition, or suggests that the study is free of severe disease. In both cases, the diagnosis should be verified by a trained physician. The clinical benefit is achieved:

Traditional CAD system usually plays the role of a "second reader" and is used after or during the interpretationperformed by physician. CAST, on the other hand, analyzes the study before the physician, in a background, fully automatic mode. By the time physician comes to read the study, the initial triage or "wet read" prepared by CAST is already available. CAST system can send a message to a physician to report an urgent case requiring immediate attention.

Sensitivity and specificity

Like any CAD system, CAST, in general, cannot guarantee 100% diagnostic accuracy. Since CAST operates in a fully automated mode, the system is expected to exhibit very high sensitivity – usually above 90%. Moreover, the need to provide a diagnosis at "per study" level dictates stringent requirements for CAST specificity as well. The average of one or more false alarms per study, tolerable for a traditional CAD, is not acceptable for CAST, as almost every study would be reported as positive. Therefore, for most clinical applications, CAST specificity should be higher than 60-70% to make it useful.

Reliability and quality control

Since CAST operates in a fully automatic mode, it should be able to deal with any study, regardless of image quality, patient anatomy, etc. Therefore, CAST systems should implement a quality control mechanism to ensure the high confidence level of the diagnosis. If the system decides (based on the evaluated image quality, detected artifacts, anatomical anomalies, etc.) that no reliable diagnosis can be automatically achieved, it reports a failure.

Clinical applications

CAST approach is applicable for the automatic detection of acute, life-threatening conditions from diagnostic medical images, such as:

CAST system can analyze images acquired with various modalities, including x-ray, CT, MRI, ultrasound and others.

Examples

CAST for coronary artery disease

CAST system is available for the detection of significant (>50%) coronary stenosis in coronary CT angiography (cCTA) studies. The system exhibits "per study" specificity of 60–70%, while keeping the sensitivity above 90%.[3] [4] [5] [6] [7] It can be used for chest pain patient triage in emergency room.

CAST for Intracranial Hemorrhages

A deep learning system is available for automatic detection of Intracranial Hemorrhages in acute care settings.[8]

See also

Notes and References

  1. Goldenberg . R . Peled . N . Computer-aided simple triage . Int J Comput Assist Radiol Surg . 6 . 5. 705–11 . 21499779 . 10.1007/s11548-011-0552-x . September 2011 . 19623223 .
  2. Echegaray. Sebastian. Zamora. Gilberto. Yu. Honggang. Luo. Wenbin. Soliz. Peter. Kardon. Randy. Automated Analysis of Optic Nerve Images for Detection and Staging of Papilledema. Investigative Ophthalmology & Visual Science. 27 September 2011. 52. 10. 7470–8. 10.1167/iovs.11-7484. 21862651. subscription.
  3. 19890640 . 10.1007/s00330-009-1644-7 . 20 . 5 . Automated computer-aided stenosis detection at coronary CT angiography: initial experience . May 2010 . Eur Radiol . 1160–7 . Arnoldi . E . Gebregziabher . M . Schoepf . UJ . 24454070 . etal.
  4. 21215663 . 10.1016/j.acra.2010.10.014 . 18 . 3 . Diagnosis of coronary stenosis with CT angiography comparison of automated computer diagnosis with expert readings . March 2011 . Acad Radiol . 324–33 . Halpern . EJ . Halpern . DJ.
  5. 22304980 . 10.1016/j.ejrad.2012.01.017 . 81 . 4 . Feasibility of an automatic computer-assisted algorithm for the detection of significant coronary artery disease in patients presenting with acute chest pain . April 2012 . Eur J Radiol . e640–6 . Kang . KW . Chang . HJ . Shim . H . etal.
  6. 22484719 . 10.1007/s11548-012-0684-7 . 7 . 6 . Computer-aided simple triage (CAST) for coronary CT angiography (CCTA) . November 2012 . Int J Comput Assist Radiol Surg . 819–27 . Goldenberg . R . Eilot . D . Begelman . G . Walach . E . Ben-Ishai . E . Peled . N. 5627031 .
  7. 23735619 . 10.1016/j.acra.2013.02.014 . 20 . 8 . Diagnostic performance evaluation of a computer-aided simple triage system for coronary CT angiography in patients with intermediate risk for acute coronary syndrome . 2013 . Acad Radiol . 980–6 . Meyer . M . Schoepf . UJ . Fink . C . Goldenberg . R . Apfaltrer . P . Gruettner . J . Vajcs . D . Schoenberg . SO . Henzler . T.
  8. Zebra Medical Vision Announces CE Approval of Its Newest AI Imaging Algorithm - Automatic Identification of Brain Bleeds https://www.businesswire.com/news/home/20180305005693/en/Zebra-Medical-Vision-Announces-CE-Approval-Newest