CT Physics

Artifacts in CT...go here

CT Dose Reduction Techniques...go here

CT Dose Reduction Techniques

See more presentations by jakey39 | Upload your own PowerPoint presentations

Dose Reduction in Diagnostic Radiology...go here

ARRT Content Specifications for CT Exam...go here

Dose in CT PowerPoint

MDCT/CTA of the Liver

Watch the video clips here:

CT Protocols Quiz 3

The deadline for this Quiz is Monday, April 12th at midnight. Type your answers in a word document (please make sure to save it in the old version of Word...with the doc extension after the file name, not the docx) and e-mail it to ctprof09@gmail.com

Questions from Part 1

1. When do we use CT in the evaluation of skeletal trauma? (Lit and describe 4 instances/situations...4 points)
2. Pertaining to CT angiograms on trauma patients what is a single phase examination, and what is a dual phase examination as it relates to administration of contrast. (1 point)
3. Regarding Kernels or reconstruction algorithms: which one provides improved edge enhancement, but increases the image noise? (1 point)
4. Volume rendering can be done with different opacities, what are the two types of V opacities mentioned in the lecture, and which one causes more artifacts? (1 point)
5. In the context of 3-D reconstruction of CT images what is disarticulation? (1 point)
6. What type and amount of contrast is used to distend the bladder for CT Cystoscopy? and what is the method of contrast administration? (1 point)

Questions from Part 2

1. List 6 indications for CT evaluation of pediatric trauma patients (3 points)
2. In the image below, what region of the scapula is fractured? (1 point)

Questions from Part 3

1. List 4 types of vascular injuries to the upper extremity, and describe them (tell me what they are in non-medical terms...4 points).
2. Outline the scan protocols for suspected vascular trauma that is shown in the presentation. (2 points)
3. What type of humeral fracture is shown in the image to the right? (1 point)
4. Based on the concluding remarks in part 3, when is CT most useful, and what are its advantages (3 points)

CT Artifacts

Here is a PDF document on CT Artifacts.

Answer the following questions based on material from the article.


CT artifacts originate from a range of sources.

Fill in the blanks for each of the different types of artifacts listed below (1-4):

1. ______________artifacts result from the physical processes involved in the acquisition of CT data.


2. Patient-based artifacts are caused by such factors as ___________________ or ________________.


3. Scanner-based artifacts result from ______________________.


4. Helical and multisection technique artifacts are produced by the ___________________.


5. What do the authors of the article consider to be the “most important factors in avoiding CT artifacts”.


6. What is the definition of the term artifact given by the author as it relates to CT?

7. List four methods/techniques used by CT equipment manufacturers to reduce beam hardening artifacts.

8. What is the best way to avoid partial volume artifacts?

9. What is milliamperage modulation, and why is it used?

10. What is cardiac gating (how does it work, and what does it do)?

Anatomy Slides

View the PowerPoint presentation "Anatomy of the Abdominal blood vessels" here

View the PowerPoint of "Vascular Anatomy" here

Spiral CT

Click link below for spiral ct handout.

Spiral CT link

Click link below for PowerPoint presentation on Spiral CT

PowerPoint


Click below for the PowerPoint on Detector Technology

Detectors Link

CT Protocols Update

The CT protocols course officially ends on April 23rd. There are only three more requirements left to be fulfilled. They are listed in numeric order below (in bold):

1. There is one more post that has to be added to your web log. This final post should expand several of the issues highlighted in the pdf file that is on your CD--titled "New Techniques in CT Angiography"

Your final post should explain each of the following: (use diagrams, pictures, and/or images to emphasize and illustrate your descriptions.)

A. What is the purpose of bolus tracking in contrast administration, and how does the method work?

B. What is Maximum Intensity Projection? Explain how it works, and provide images as examples of the technique.

C. What is Segmentation? Explain how it works, and provide images as examples of the technique.

The Web log is due on April 23rd. Once it is complete, send me an e-mail with the exact web address in the body of the e-mail. The subject of the e-mail should be "Web Log" (exactly that, and nothing else).

2. The final quiz will be administered on April 23rd and it is based on the two video clips on your CD.

3. A online practice quiz will be available on April 16th. It will be a combination of questions from the pdf file and the two video clips.

My wish is that you have developed an appreciation for the advances in Computed Tomography over the past 35 years–from the first-generation machine of the early days, to the 64 slice Multi-detector CT machines that are in routine use today. The scan parameters and techniques have changed, and so has the terminology of CT scanning. It is essential that you advance with the technology.

Thanks.