Topic
Imaging and radiology
How medical imaging is chosen, read, and validated, and when a scan helps or misleads.
This page collects every article by Dr. Damon Tojjar in this topic. For all topics see browse by topic, and for the source-anchored record see damontojjar.com/record.
Articles in this topic (19)
- What ALARA Really Means and How to Read a CT Radiation Dose
What ALARA Really Means, and How to Read a CT Radiation DoseALARA stands for As Low As Reasonably Achievable, and the word doing the work is reasonably. The...
- Contrast-Induced Versus Contrast-Associated Kidney Injury: A Lesson in Confounding
Contrast-induced injury means the iodinated dye caused the damage; contrast-associated injury means the creatinine rose after a contrast scan for any reason,...
- Dense Breasts and Supplemental Screening: What the National Notification Rule Does and Does Not Prove
Dense Breasts and Supplemental Screening: What the National Notification Rule Does and Does Not ProveSince September 10, 2024, the FDA's MQSA final rule requires...
- Do CT Scans Cause Cancer? How to Weigh the Linear No Threshold Model
CT scans do deliver ionizing radiation, and radiation can cause cancer, so the honest answer is a qualified yes: a single medically justified scan carries a very...
- Gadolinium Contrast Safety: What the ACR Group I Versus Group II Classification Means
The short answerThe American College of Radiology (ACR) sorts gadolinium-based contrast agents into three groups based on how many cases of nephrogenic systemic...
- How the ACR Appropriateness Criteria Turn Evidence Into an Imaging Recommendation
The ACR Appropriateness Criteria convert medical evidence into an imaging recommendation through a structured two-part engine. First a systematic literature review...
- How Lung-RADS Turns a Lung Nodule Into a Management Plan
A Lung-RADS score is a radiologist's structured translation of a pulmonary nodule into an estimated probability of cancer and a matching next step. Built by the...
- How to Judge an FDA Cleared Radiology AI Tool
Key takeaways
- Incidentalomas, How Radiologists Decide What Is Worth Chasing
The short answerAn incidentaloma is a finding no one was looking for, a spot the scan turned up while imaging was ordered for something else entirely. Radiologists...
- The Evidence Behind Lung Cancer Screening: NLST, NELSON, and Number Needed to Screen
Two adequately powered randomized trials anchor the case for lung cancer screening. In the National Lung Screening Trial (NLST), three annual low-dose CT (LDCT)...
- The First Randomized Trial of AI in Mammography: Reading the MASAI Results
MASAI is the first randomized controlled trial to test artificial intelligence inside a working breast-screening program, and its final results, published in The...
- MRI Safety: Why the Magnet Is Always On and What That Means for Implants
The magnet never turns off, and that is the whole pointThe MRI magnet is always on. A clinical scanner is built around a superconducting magnet that holds its field...
- PSMA PET for Prostate Cancer: How the proPSMA Trial Changed Staging
The proPSMA trial, a prospective randomised study run across 10 Australian centres and published in The Lancet in 2020, showed that a single PSMA PET-CT scan stages...
- Reading a PI-RADS Score: What Prostate MRI Can and Cannot Tell You
What a PI-RADS score actually reportsA PI-RADS score is a five-point rating a radiologist assigns to a suspicious area on a prostate MRI, running from 1, where...
- TI-RADS and the Problem of Finding Thyroid Cancers That Never Needed Finding
The Thyroid Imaging Reporting and Data System (TI-RADS) published by the American College of Radiology in 2017 was built to answer one narrow question: which...
- Ultrasound First for Kidney Stones: What the STONE Trial Showed
The STONE trial, published in the New England Journal of Medicine in 2014, asked whether emergency clinicians could begin the workup of a suspected kidney stone...
- What an FDG-PET Scan Measures, and Why the SUV Number Can Mislead
An FDG-PET scan does not photograph cancer. It maps where cells are consuming a radioactive glucose look-alike, and the SUV, or standardized uptake value, is a...
- Whole Body MRI Screening: What the Evidence Says About Scanning Healthy People
Whole body MRI marketed to healthy adults promises to catch cancer and other hidden disease before symptoms appear, yet the published evidence does not show that...
- Why a BI-RADS 4 Mammogram Is Not a Diagnosis
A suspicious mammogram is a reason to look closer, not a conclusionA BI-RADS 4 mammogram is a risk category, not a diagnosis. It tells you that a radiologist saw...