The Resident Roentgen File, May 2021

Volume 1, Issue 2: May 2021

A brand-new monthly newsletter specifically for radiology residents, The Resident Roentgen File curates multimedia educational resources from our vast portfolio of benefits to help ARRS Resident Members prepare for exams, fellowship, and beyond.


Mindy Wang

Diagnostic Radiology Resident, University of Texas at Houston
Vice-Chair, ARRS Resident Advisory Subcommittee


The first and oldest radiological society in North America, the American Roentgen Ray Society (ARRS) remains a prestigious organization with members all over the world. As a second-year radiology resident and first-time attendee, I was intrigued by what the 2021 ARRS Annual Meeting would bring. Despite being forced to go virtual in the midst of the COVID-19 pandemic, the meeting platform did not constrain my educational opportunities. This week-long meeting was filled with numerous educational sessions, including those in the Radiology Review Track, E-Posters, and Scientific Abstracts. A dedicated Resident Track and Trainee Social Hour were also included. Topics varied from “Financial Literacy for Radiologists” to “Tips in Interpreting the Chest Radiograph.” In the Connection Quad, attendees participated in daily case challenges, visited exhibitors, and competed for prizes. The amount of learning and diverse radiology content at ARRS 2021 was endless. Fortunately, all registrants have access to the complete meeting program on-demand through April 22, 2022; I will certainly need the extended time to view all the content!

As a trainee, I found the ARRS Annual Meeting a terrific venue for inspiration, learning, and networking. I look forward to the next meeting on May 1-5, 2022, hopefully in person in New Orleans, LA.

If you would like to become a member of ARRS, please visit the membership webpage here. Residents and fellows can enjoy free membership! Year-round, ARRS hosts remarkable educational resources just for trainees, including multimedia American Journal of Roentgenlogy (AJR) content, free ARRS Web Lectures and Online Courses, as well as Roentgen University. Be sure to follow @ARRS_Radiology on Twitter for updates. 

AJR Editor’s Choice for Residents

Each month, AJR Editor in Chief Andrew Rosenkrantz handpicks an article to highlight for ARRS Resident Members. This month’s Editor’s Choice article, by Liu et al., is: “Determining a Threshold of Medial Meniscal Extrusion for Prediction of Knee Pain and Cartilage Damage Progression Over 4 Years: Data From the Osteoarthritis Initiative.”

Authors’ rationale—An absolute extrusion distance of 3 mm is widely used to define medial meniscal extrusion (MME) of the knee, though this threshold was not based on strong evidence when originally published.

Sample—A total of 235 patients randomly selected from the Osteoarthritis Initiative cohort.

Imaging test—The study used 3-T knee MRI at baseline and at 48-month follow-up.

Readers—A single musculoskeletal radiologist reviewed all examinations; a second radiologist measured MME in a random subset of 20 knees to assess interobserver agreement.

Outcome—Knee pain progression, medial compartmental cartilage damage progression, and medial tibial cartilage damage progression, over the 4-year period.

What the authors found—Across a range of tested thresholds, a threshold MME of 2.5 mm maximized the mean of the product of sensitivity and specificity for the three outcome variables. The assessment of interreader agreement of MME measurements showed an intraclass correlation coefficient of 0.981.

Authors’ insight—A standardized threshold MME of 2.5 may be optimal for characterizing patients’ risk for structural and symptomatic progression of knee osteoarthritis.

A New Medial Meniscal Extrusion Threshold Relating Clinical Symptoms and MRI Findings

Listen to Drew Gunio explain why 2.5 mm may now be the new number to consider when reporting medial meniscal extrusion.


Additionally, please see the Editorial Comment by Judy S. Blebea discussing this article.


AJR Podcasts by Residents and Fellows

Subscribe to AJR Podcasts and listen in as our team of senior Resident and Fellow Podcast Editors critique articles and provide synthesized overviews of timely research from the “yellow journal” for in-training and practicing radiologists.


Resident ARRS Web Lecture

This month’s Web Lecture specially selected for ARRS Resident Members is “Musculoskeletal Ultrasound,” presented by J. Jacobson, T. Morgan, and Y. Endo.

After completing this series of three lectures, residents should be able to:

  • Discuss the assessment of superficial and soft-tissue abnormalities in musculoskeletal ultrasound;
  • Describe ultrasound imaging features of groin hernias;
  • Discuss ultrasound-guided interventions for nerve entrapment.

How residents and fellows can sign up for free ARRS membership:

  1. Complete the ARRS membership application online
    Go to our Membership Application Page. Select In-Training Members and complete the application online.
  2. Complete the membership application and fax or mail to ARRS
    Complete the ARRS In-Training Membership Application and fax or mail the application to ARRS.

The Resident Roentgen File Archives: