How to Read Your Radiology Report: A Radiologist's Guide

A radiology report is the written interpretation of your scan by a radiologist, and the way to read it is to go to the impression first, then back to the findings, then to the comparison and clinical information that explain why the radiologist wrote what they wrote. This guide to how to read your radiology report follows the order a radiologist uses when checking a colleague's report, explains the phrases that decide the next step, and shows when a second read of the images, not the text, is worth asking for.

What a radiology report is and who writes it

A radiologist is a physician who specialises in interpreting medical images. The report is their formal answer to the question your referring doctor asked when ordering the scan. It is a legal medical document, it is written for the referring physician rather than for you, and its structure is remarkably consistent across countries because professional bodies prescribe it.

The European Society of Radiology's good-practice guideline for reporting describes what a report should contain: the clinical question, the technique, the findings, a comparison with earlier examinations, and a conclusion with recommendations (ESR, Good practice for radiological reporting, Insights into Imaging, 2011). The same society has argued since 2018 for structured reports with a fixed order of sections for the same reason: a consistent structure makes a report easier to check and harder to misread (ESR paper on structured reporting, Insights into Imaging, 2018).

Reports in Switzerland, Germany, the UK and North America follow the same logic even when the headings differ. Once you know the sections, you can read a report from any of these systems.

How to read your radiology report section by section

Patient education material from RSNA and the ACR describes six sections: the type of examination, the clinical history, the comparison with prior imaging, the technique, the findings and the impression (RadiologyInfo.org, 2024). A radiologist reviewing a report does not read them top to bottom. The practical order is impression, findings, comparison, clinical information and technique.

Clinical information and technique

The clinical information is the question the report tries to answer. "Right knee pain after a fall, rule out meniscal tear" tells you what the radiologist was focusing on and, by implication, what they may have spent less time on. If the clinical information is vague or wrong, the report may answer the wrong question, and that is one of the most common reasons an otherwise competent report misses the point.

The technique states what was done: which body region, which sequences on MRI, whether contrast was given, whether the study was limited by motion or metal. A line such as "limited examination due to patient motion" is not a formality. It lowers the confidence of everything that follows and is a reason to ask whether a repeat scan or a second read makes sense.

Comparison with earlier imaging

The comparison statement names the earlier studies the radiologist had and the date of each. "No prior studies available" is a sentence worth noticing, because many findings only become interpretable over time: a 5 mm lung nodule that is unchanged over two years is treated very differently from one that is new. If you know that earlier scans exist and the report says none were available, the radiologist did not see them, and a review that includes them can change the conclusion.

Findings

The findings describe what the images show, organ by organ or region by region, including normal structures. Words such as "unremarkable" and "normal" are positive statements that the structure was examined and nothing abnormal was seen. Measurements belong here, usually in millimetres with the series and image number, so that the next radiologist can find and measure the same thing.

Impression

The impression is the summary and the only section most referring doctors read in full. It answers the clinical question, lists the important findings in order of importance, gives a likely diagnosis or a short list of possibilities, and states what should happen next: nothing, a follow-up scan at a stated interval, a different examination, a biopsy, or a referral. If the impression and the findings seem to disagree, the impression is what the radiologist meant.

The words that carry the decision

Three kinds of sentence decide what happens after a report, and they are worth reading slowly.

The first is confidence wording. "Consistent with" and "compatible with" mean the appearance fits the diagnosis well, and "suspicious for" and "concerning for" mean the radiologist thinks the diagnosis is likely enough to act on.

"Cannot be excluded" and "not excluded" mean the images cannot rule it out, which is weaker than saying it is likely. "No evidence of" means the radiologist looked and did not see it, within the limits of the examination.

The second is the incidental finding. An incidental finding is something unrelated to the reason for the scan, such as a small kidney cyst on a spine MRI. Most are harmless, and the report usually says so. Some carry a follow-up recommendation written to a published guideline, and the guideline, not the size alone, decides whether follow-up is needed.

The third is the follow-up recommendation, which is often the sentence that generates the most anxiety and the most unnecessary imaging. Follow-up intervals come from guidelines. The Fleischner Society, for example, recommends no routine follow-up for a solid lung nodule under 6 mm in a patient at low risk, while larger or growing nodules have defined intervals (Fleischner Society guidelines, Radiology, 2017). When a report recommends follow-up, it is reasonable to ask which guideline the interval comes from and whether your own risk factors were part of that decision.

What the radiologist checks before signing

In our reading room a report is checked in a fixed order, and knowing that order tells you where reports tend to go wrong.

The first check is whether the clinical question was answered in the impression. The second is whether every measurement in the findings is reproducible, with a series and image number, so that a future reader can compare like with like. The third is the comparison: every prior study that was available is named, and every finding that existed on a prior study has a statement about change, no change or resolution. The fourth is the search outside the clinical question, because a radiologist asked about the meniscus still has to look at the bone marrow, the cartilage and the soft tissues, and the most common serious error in radiology is the finding that was visible but not looked at.

The fifth check is wording. A finding that needs action must be in the impression with a clear recommendation, and a finding that needs urgent action must be communicated directly to the referring doctor, not left in a report that may be read days later. The ESR guideline sets out this duty to communicate urgent and unexpected findings directly rather than only in writing (ESR, Good practice for radiological reporting, Insights into Imaging, 2011).

A good report, read against these five checks, answers the question, measures what it describes, compares with the past, looks beyond the question, and says what should happen next. A report that fails one of them is not necessarily wrong, but it is one where a second read adds the most.

How often reports differ between radiologists

Interpretation is a judgement, and judgements differ. A review of the evidence by Brady estimated that day-to-day discrepancies affect about 3 to 5 percent of studies reported in routine practice, with higher rates found when examinations are reviewed retrospectively or when specific findings are searched for (Brady, Insights into Imaging, 2017). Most of these discrepancies are minor and do not change treatment.

Formal second reads tell a different story because they are requested in difficult cases. A meta-analysis of 29 studies with 12'676 secondary interpretations, performed by radiologists on examinations first reported elsewhere, found a discrepancy with the first report in 32.2 percent of cases, a discrepancy in major findings in 20.4 percent, and a change in management in 18.6 percent (Rosenkrantz et al., Journal of the American College of Radiology, 2018). Where a reference standard was available, the second interpretation was the accurate one in 90.5 percent of discrepant cases. Rates were 31.2 percent for MRI, 28.3 percent for CT, 39.9 percent for breast imaging, 34.0 percent for musculoskeletal imaging and 23.8 percent for neuroradiology.

These figures come from tertiary and academic centres, most of them in oncology, where patients are referred precisely because the case is complex, so they overstate the risk for a routine scan and they describe the whole range from wording differences to missed diagnoses. They do not mean that your report is likely to be wrong. They mean that a second, independent look is a normal part of how radiology controls its own quality, which is why hospitals run double reading in screening mammography and multidisciplinary tumour boards review images before treatment decisions.

When a second read of your images is worth it

A second read is a fresh interpretation of the images by another radiologist, ideally a subspecialist in the relevant body region, who writes a report of their own and states where they agree and disagree with the first. It is most useful in five situations.

The first is a decision that depends on the read: an operation, a biopsy, the start of a long treatment, or a decision not to treat. The second is a report whose wording is uncertain, with "cannot be excluded" or a list of possibilities and no recommendation. The third is a limited examination, where motion, metal or an incomplete protocol is noted.

The fourth is a report without comparison when earlier scans exist. The fifth is a finding in a subspecialty, such as a prostate MRI, a breast MRI or a complex spine, reported by a general radiologist.

A second read also has limits. It cannot add sequences that were not acquired, it cannot replace a clinical examination or laboratory results, and when the first report is clear and complete it will usually confirm it. Confirmation has its own value before a major decision, but it is a different outcome from a changed diagnosis, and a reputable service will tell you in advance that both are possible.

What to do with your report before your appointment

If your result appeared in a patient portal before your doctor has discussed it, read the impression, note any recommendation, and write down the questions it raises rather than searching each term on its own. Bring the report and, if you can, the images to the appointment. The report describes the pictures; the pictures are the evidence.

If you want an independent read, request the images as DICOM files from the imaging centre, on a CD or as a download link, together with the written report and any earlier scans of the same region. Send them with your questions, in writing, to the service you choose. A report from Alpine Diagnostics answers each question you submit, names the radiologist who read the images, and states where the second interpretation agrees or differs from the first and why. For MRI examinations, the MRI second opinion page describes what is included; the frequently asked questions cover file formats, delivery times and languages, and the second opinion before surgery page explains the pre-operative review.

When a decision depends on the read, a single-region review by a subspecialist radiologist gives you a second written interpretation with every question answered.