• DVM360_Conference_Charlotte,NC_banner
  • ACVCACVC
  • DVM 360
  • Fetch DVM 360Fetch DVM 360
DVM 360
dvm360 | Veterinary News, Veterinarian Insights, Medicine, Pet Care
dvm360 | Veterinary News, Veterinarian Insights, Medicine, Pet Care
By Role
AssociatesOwnersPractice ManagerStudentsTechnicians
Subscriptions
dvm360 Newsletterdvm360 Magazine
News
All News
Association
Breaking News
Education
Equine
FDA
Law & Ethics
Market Trends
Medical
Politics
Products
Recalls
Regulatory
Media
dvm360 LIVE!™
Expert Interviews
The Vet Blast Podcast
Medical World News
Pet Connections
The Dilemma Live
Vet Perspectives™
Weekly Newscast
dvm360 Insights™
Publications
All Publications
dvm360
Firstline
Supplements
Vetted
Clinical
All Clinical
Anesthesia
Animal Welfare
Behavior
Cardiology
CBD in Pets
Dentistry
Dermatology
Diabetes
Emergency & Critical Care
Endocrinology
Equine Medicine
Exotic Animal Medicine
Feline Medicine
Gastroenterology
Imaging
Infectious Diseases
Integrative Medicine
Nutrition
Oncology
Ophthalmology
Orthopedics
Pain Management
Parasitology
Surgery
Toxicology
Urology & Nephrology
Virtual Care
Business
All Business
Business & Personal Finance
Hospital Design
Personnel Management
Practice Finances
Practice Operations
Wellbeing & Lifestyle
Continuing Education
Conferences
Conference Listing
Conference Proceedings
Upcoming dvm360 Conferences
Resources
CBD in Pets
CE Requirements by State
Contests
Partners
Spotlight Series
Team Meeting in a Box
Toolkit
Top Recommended Veterinary Products
Vet to Vet
Veterinary Heroes
  • Contact Us
  • Fetch DVM360 Conference
  • Terms and Conditions
  • Privacy
  • Do Not Sell My Information
  • About Us

© 2023 MJH Life Sciences and dvm360 | Veterinary News, Veterinarian Insights, Medicine, Pet Care. All rights reserved.

Advertisement
By Role
  • Associates
  • Owners
  • Practice Manager
  • Students
  • Technicians
Subscriptions
  • dvm360 Newsletter
  • dvm360 Magazine
  • Contact Us
  • Fetch DVM360 Conference
  • Terms and Conditions
  • Privacy
  • Do Not Sell My Information
  • About Us
  • MJHLS Brand Logo

© 2023 MJH Life Sciences™ and dvm360 | Veterinary News, Veterinarian Insights, Medicine, Pet Care. All rights reserved.

When to choose CT vs. MRI (Proceedings)

August 1, 2011
Seth Wallack, DVM, DACVR

I'm not telling you something you don't already know when I write that radiographs are not the end all for diagnostic imaging. X-rays were discovered in 1895 and as with any old technology it is typically the least informative. Newer imaging technologies will always provide more information.

I'm not telling you something you don't already know when I write that radiographs are not the end all for diagnostic imaging. X-rays were discovered in 1895 and as with any old technology it is typically the least informative. Newer imaging technologies will always provide more information. However radiographs will remain the first line of imaging for quite some time due to their ease of use, low cost and global assessment.

One of the old thought processes associated with CT and MRI is the need to go to surgery immediately following imaging. This mindset needs to change for several reasons. First, studies performed on morbidity and mortality associated with anesthesia in both humans and animals did not find a link between the number of anesthetic procedures and complications. Complications are associated with sickness and extremely sick animals should not be undergoing an MRI anyway. Extremely sick animals should have rapid assessment imaging and then surgery. For stable patients receiving a CT or MRI I do not recommend rushing into surgery unless there is a critical finding. CT and MRI studies consist of hundreds of images and to thoroughly review these images for all the information takes more time than the journey between imaging and the OR. The old adage "Measure twice, cut once" will serve you well in this situation.

Computed Tomography or CT uses x-rays to obtain the image and the computer to display the image. CT scans provide excellent spatial resolution and fair contrast resolution. Soft tissues on CT are not well separated.

Magnettic Resonance Imaging or MRI uses magnetic fields, specific frequencies and the computer to display the image. MRI provides fair spatial resolution (at lower field strengths) and excellent soft tissue contrast resolution. MRI is particularly useful in identifying regions of edema or inflammation which translates into pathology.

While there are many cases that could be imaged with either CT or MRI there are specific instances where one imaging modality is preferred over the other. The following is a partial list of those cases.

Advertisement

Nasal disease

CT is preferred over MRI due to fine turbinate detail however MRI would be preferred over CT if brain signs are present.

Ear disease

CT is preferred over MRI due to fine turbinate detail however MRI would be preferred over CT if brain signs are present.

Orbital disease

MRI is preferred over CT. If CT is the only option then both axial and coronal images should be obtained. Coronal images are done by placing the patient in dorsal recumbency and pointing the nose up.

Brain disease

MRI is preferred over CT. If CT is the only option then both pre and post-contrast axial images should be obtained. Meningiomas and pituitary masses will show up on post-contrast images.

Cervical disease

MRI is preferred over CT. If CT is the only option then a CT myelogram should be performed.

Thoracic or lumbar disease

MRI is preferred over CT. If mineralized discs are present then plain CT is fine due to the epidural fat around the spinal cord. For other CT studies a CT myelogram may be necessary.

Shoulder or brachial plexus

MRI is preferred over CT. If CT is the only option then IV contrast should be used for brachial plexus tumors.

Elbow disease

CT is preferred over MRI due to spatial resolution.

Pulmonary disease/ mets

CT. MRI can be used for cardiac evaluation.

Abdominal disease

CT or MRI with contrast. For IVP then CT.

L-S or Stifle disease

MRI is preferred over CT for both.

Related Content:

Imaging
Making waves in sea turtle conservation
Making waves in sea turtle conservation
Amwell Data Services offers independent consulting on veterinary imaging equipment
Amwell Data Services offers independent consulting on veterinary imaging equipment
Top dvm360 articles of 2022: #9
Top dvm360 articles of 2022: #9

Advertisement

Latest News

Partners for Health Pets and VHMA collaboration publish white paper

Vetstoria releases its Fill Rate platform

What's new with the "Dentistry Lane" across the veterinary profession?

Meet the BlackDVM Network

View More Latest News
Advertisement