Why does a memory-loss MRI contain so many scores?

A brain MRI performed for memory or behavior changes may list several grading systems side by side. Common examples include the Fazekas score for white-matter changes, global cortical atrophy (GCA), medial temporal atrophy (MTA) and the Koedam score for posterior or parietal atrophy.

Some reports even print the full definition of every grade. That can make the results look like a dementia checklist, but these scores are descriptive tools—not diagnoses. Radiologists use them to communicate where changes are located and how noticeable they appear.

A score describes an MRI feature. It does not, by itself, establish Alzheimer’s disease or another cause of cognitive symptoms.

Fazekas score: white-matter vascular change

The Fazekas scale grades bright areas in the brain’s white matter, often called white-matter hyperintensities, small-vessel ischemic change or vascular leukopathy. It usually runs from 0 to 3:

Fazekas 0: No white-matter lesions.
Fazekas 1: A few small, separate spots.
Fazekas 2: Spots beginning to merge into larger areas.
Fazekas 3: Extensive, confluent white-matter abnormality.

A French report stating “leucopathie vasculaire, grade II de Fazekas” is describing moderate white-matter change generally attributed to small-vessel disease. It is not saying that a major stroke occurred.

These changes become more common with age and are associated with factors such as high blood pressure, diabetes, smoking and other blood-vessel risks. They may contribute to slower thinking, reduced attention, walking difficulty or executive-function problems when the burden is substantial. A Fazekas score does not reveal how much a particular person’s symptoms come from those changes.

GCA score: overall brain volume loss

The GCA scale grades widening of the grooves over the brain and enlargement of fluid spaces, which are indirect signs of cortical volume loss. A common 0–3 system is:

GCA 0: No visible cortical atrophy.
GCA 1: Mild widening of the grooves.
GCA 2: Moderate volume loss.
GCA 3: Severe volume loss with marked widening and thinning.

“Moderate cortico-subcortical atrophy” similarly means volume loss involving the brain’s outer cortex and deeper structures. The distribution matters. For example, a report noting no frontal predominance is saying that the frontal lobes are not disproportionately affected—a detail that may be relevant when clinicians consider frontotemporal disorders.

MTA score: the memory-related medial temporal lobes

The MTA scale examines structures deep in the temporal lobes, especially the hippocampi, which are important for forming new memories. The commonly used Scheltens MTA scale runs from 0 to 4:

MTA 0: No atrophy.
MTA 1: Minimal widening around the hippocampus.
MTA 2: Mild loss of hippocampal height with wider surrounding spaces.
MTA 3: Moderate hippocampal volume loss.
MTA 4: Severe volume loss.

Prominent MTA can support an Alzheimer’s-type pattern, particularly when memory testing shows difficulty learning and retaining new information. However, hippocampal shrinkage is not unique to Alzheimer’s disease. It can occur with normal aging and several neurological or medical conditions.

Reports may score the left and right sides separately. A small side-to-side difference is not automatically meaningful; clear asymmetry is interpreted alongside symptoms and other MRI findings.

Koedam score: posterior and parietal atrophy

The Koedam scale grades atrophy toward the back and upper part of the brain, including the parietal and posterior cingulate regions:

Koedam 0: No posterior atrophy.
Koedam 1: Mild posterior widening.
Koedam 2: Moderate posterior atrophy.
Koedam 3: Severe posterior atrophy.

Parietal-predominant atrophy can indicate an early Alzheimer’s-type process, especially when it appears with MTA and a compatible clinical history. But “can indicate” expresses possibility, not certainty. A mild, unchanged posterior pattern without clear hippocampal involvement may not form a classic dementia-specific pattern.

What is normal for age?

There is no universal decade-by-decade cutoff that applies to every scanner, scoring method and patient. Radiologists consider age, image quality, medical history, symmetry and whether findings have changed over time.

In the 40s and 50s: Pronounced atrophy or confluent white-matter disease is less expected and usually receives closer attention. A few tiny white-matter spots can still occur.
In the 60s: Mild generalized volume loss and small scattered white-matter spots become more common. Focal or disproportionate atrophy remains more informative than mild global change.
In the 70s: Mild GCA, some MTA and Fazekas 1 changes are frequently encountered. An MTA score of 2 may be more concerning in a younger person than in someone in the later decades of life.
In the 80s and beyond: Greater atrophy and white-matter burden are more common, so a score becomes less specific. High grades, strong asymmetry, a characteristic regional pattern or clear progression may carry more weight.

Age-adjusted thresholds vary among hospitals. This is why a printed score legend should not be read as an age-normality chart.

How doctors interpret combinations of findings

The most useful information often comes from the pattern across scores:

MTA plus parietal atrophy: May support an Alzheimer’s-type pattern when symptoms and cognitive testing agree.
Fazekas 2 or 3 with lacunes or prior small strokes: Raises the possibility of vascular contributions to cognitive difficulty.
Frontal or anterior temporal predominance: Can suggest a frontotemporal pattern, although MRI alone cannot diagnose it.
Mild global atrophy without regional predominance: Is relatively nonspecific and may overlap with aging.
Atrophy plus vascular disease: May suggest mixed contributors rather than one single cause.

An unchanged MRI is generally evidence against rapid structural progression during the interval studied. It does not exclude a cognitive disorder, because symptoms and testing can change before—or without—an obvious change on routine MRI.

What the MRI cannot answer

MRI helps identify patterns and rule out problems such as a mass, large stroke, fluid-pressure disorder or bleeding. It cannot independently determine whether forgetfulness is caused by Alzheimer’s disease, vascular disease, sleep problems, medication effects, depression, hearing loss or another condition.

Clinicians combine imaging with the symptom timeline, neurological examination, cognitive testing, daily functioning, laboratory results and sometimes biomarker tests.

When to talk to your doctor

Ask the ordering clinician how the scores compare with what is expected for the person’s age, whether the pattern matches the reported symptoms and whether vascular risk factors need attention. Prompt medical assessment is important for sudden confusion, new weakness, speech difficulty or another abrupt neurological change.

This article provides general education and is not a diagnosis or individual medical advice.

Fazekas, GCA and MTA Scores on a Memory MRI