Wednesday, December 15, 2010

Dec 15th Quiz

Complete the quiz by 7:30 pm. For the quiz, put your name and e-mail address in the appropriate box as ususal.

Also, complete the course evaluation. For the course evaluation, do not put your name in the name box, put MR Protocols.

  • Click here for the Quiz
  • Click here for the course evaluation 

Monday, December 13, 2010

MRI Artifacts Assignment

The following questions are due by Wednesday, Dec 15th at 8:00 pm.

Search the internet and find two pictures of each of the following Artifacts: Aliasing, Chemical Shift, Zipper.

Copy and paste the images into a word document and describe how each artifact is produced and how it can be eliminated.

Also, discuss 3 ways that the appearance of motion can be reduced or eliminated from an MR image.

Monday, December 6, 2010

MRI Pulse Sequences

Click here for full screen version.

MR Assignment for December 8th, 2010

Read chapter 5 of your textbook and answer the following questions (Print the answers and bring it to class on Wednesday).

Draw and label pulse sequence diagrams for each of the following (1-4):

1. Conventional Spin Echo

2. Dual Echo Spin Echo

3. Fast Spin Echo

4. Inversion Recovery

5. What parameters (TR and TE) would you use to produce T1 (t-one) weighting in a spin echo pulse sequence?

6. What do the initials ETL, and ETE stand for, what pulse sequence do they apply to, and give another term used instead of ETL?

7. What parameters (TR, TE and TI) would you use to achieve proton density weighting in Inversion recovery?

8. Give the main reasons for using a Short tau inversion recovery(STIR) sequence?

9. List two advantages and one disadvantage of a gradient rephased echo (GRE) sequence compared to a conventional spin echo sequence?

10. How does T2* differ from T2 weighting?

Tuesday, November 16, 2010

Important Announcement

There will be no in-person class on November 17th, 2010.

I will provide the lecture notes and other information on this web site.

The next class session will be on December 1st.

More information will follow.

Monday, November 15, 2010

MR Safety Quiz Questions

Deadline: November 24th. (Any time before Thanksgiving)

To answer the following questions refer to the 6 links listed on the web log as “Useful Online Resources”
Type your answers in complete, grammatically correct sentences. 

If you quote directly from a particular resource cite your source by placing the Link number and page number in parentheses after the quote. For example, this is how you should signify that you are using the exact words from an article: “Patients shall be pre-screened for contraindications and informed about MRI safety considerations”(Link 2, pg.9).

Question 1
In order to ensure safety to patients and employees using an MRI facility, the MR suite is setup according to specific areas or zones. Describe each of the four zones, giving an example of an area in the MR unit that would fall in each zone. (Write one paragraph minimum for each zone. Information can be found in Link 1 and Link 2)

Question 2
In the ACR guidelines (Link 1) Personnel  Definitions are provided. What are these definitions and how are they relevant to MR safety?

Question 3
Based on the ACR document (Link 1) regarding  “Patients in Whom There Are or May Be Intracranial Aneurysm Clips”, what are the guidelines/recommendations to ensure the safety of such patients in the MR environment? (Your answer should be at least 15 long)

Question 4
Based on the ACR document (Link 1) regarding  “Patients in Whom There Are or May Be Cardiac Pacemakers or Implantable Cardioverter Defibrillators”, what are the guidelines/recommendations to ensure the safety of such patients in the MR environment? (Your answer should be at least 15 long)

Question 5
Regarding the safe use of MR contrast agents, what do the terms NSF and GFR mean, and what’s their relevance to the use of contrast agents in MRI?  (4 sentences minimum)

Question 6
What are the ACR recommendations regarding the screening of pediatric patients? (3 paragraphs minimum).

Question 7
What are the ACR recommendations regarding MRI procedures on patients who are or may be pregnant?  (3 paragraphs minimum).

Question 8
Fill in the missing information in the following statement:

U.S. Food and Drug Administration labeling criteria (developed by ASTM [American Society for Testing and Materials] International) for portable objects taken into Zone IV.  Square green label is ______________for wholly nonmetallic objects, triangular yellow label is for objects with ______________rating, and round red label is for objects that are _________________.

Which type of materials are classified as “MR conditional? (Refer to Link 3, page 36)

 Question 9
Discuss the bio-effects and potential hazards of static magnetic fields, gradient fields and radiofrequencies used in MRI (3 paragraphs minimum)

Question 10
What is SAR, on what basis is it calculated, and what are the FDA approved  limits for the whole body and specific anatomic regions?

Wednesday, November 10, 2010

MRI Safety (Lecture 11-10-2010)

There are potential risks in the MR environment... (American College of Radiology (ACR) Guidance Document for Safe MR Practices) 

The goal of the lecture is to highlight the potential risks to patients, family members, visitors, and staff; and explore safe practice guidelines and recommendations.

The fundamental principles involved in MR site planning are discussed, and additional sources of information on MRI safety are listed.

Useful Online Resources

1. ACR Guidance Document for Safe MR Practices: 2007--This document covers topics such as MR Safety Policies and Procedures, Static Magnetic Field Issues, Patient and non-MR personnel screening, pregnancy-related issues, pediatric MR safety concerns, contrast agent safety, etc...

2. MRI Safety: 2009--This document covers zoning, screening, and emergency procedures very well with great illustrations and graphics.

3. MRI Safety Issues--This document covers the biologic effects of the static magnetic field, time varying magnetic fields (the gradients), and RF energy. It lists various reported causes of death related to MR, and provides illustrations of the new FDA MR safety terminology.

4. PowerPoint Presentation on safety concerns, specifically geared towards non-MR health care providers. (PowerPoint Below).

5. MR Safety July-2007

6. Video on MR Safety