# Koedam PA — Koedam posterior atrophy visual rating scale

> Bilateral 0-3 visual MRI rating of posterior cingulate and parieto-occipital sulci plus precuneus and parietal-lobe atrophy. Score each side in sagittal, axial and coronal planes and retain the worst plane per side; any bilateral aggregate must be named. Age and asymmetry remain visible, and the scale is neither an Alzheimer biomarker nor a grade-only treatment rule.

**Situação:** vigente · **Órgão:** Encéfalo · **Órgão emissor:** Koedam et al. / dementia imaging literature · **Versão:** 2011 original bilateral three-plane MRI scale; 2019 age norms; 2024 Alzheimer biological boundary · **Ano:** 2011

## Procedência e vigência
- Família: léxico
- Tipo de lógica: flat
- Modalidade: MRI
- Fonte primária: Koedam ELGE, Lehmann M, van der Flier WM, et al.. Visual assessment of posterior atrophy: development of a MRI rating scale (2011) — https://pmc.ncbi.nlm.nih.gov/articles/PMC3217148/
- Última verificação: 2026-07-24
- Última checagem: 2026-08-12

## Lógica de decisão
Return two side-specific grades plus the decisive planes. Never collapse them silently, interpret them without age, or convert a posterior atrophy pattern into Alzheimer diagnosis, individual prognosis or treatment.

## Categorias

| Código | Rótulo | Critérios | Conduta | Risco | Localizador | Verificado |
| --- | --- | --- | --- | --- | --- | --- |
| 0 | Grade 0 | Per hemisphere, grade 0 requires closed posterior cingulate and parieto-occipital sulci and closed parietal-lobe and precuneus sulci without posterior atrophy. Inspect sagittal T1, axial FLAIR and coronal T1 and retain the highest valid plane score for that side. | No Koedam grade defines treatment. A grade-0 posterior pattern does not exclude Alzheimer disease or another cause of cognitive symptoms; continue or tailor evaluation from the clinical phenotype, other imaging axes and biomarkers when clinically indicated rather than stopping work-up from this score alone. | Grade 0 is the lowest posterior-atrophy morphology, but it is not a negative Alzheimer biomarker and does not predict an individual's future cognition. The original study assessed group discrimination, not per-grade personal risk. | Koedam et al. 2011, DOI 10.1007/s00330-011-2205-4, PMC3217148, Methods: grade 0 landmarks, bilateral assessment, three planes and highest-plane rule; Jack et al. 2024, DOI 10.1002/alz.13859, biological Alzheimer boundary. | ✓ |
| 1 | Grade 1 | Per hemisphere, grade 1 is mild widening of the posterior cingulate and parieto-occipital sulci with mild parietal and precuneus atrophy, but without evident gyral volume loss. The final side score is the worst supported sagittal, axial or coronal score. | Treat grade 1 as an age-aware descriptive finding. It is common in cognitively intact adults and does not independently trigger biomarkers, medication, surveillance or a dementia label; correlate with age, symptoms, asymmetry, medial-temporal and global atrophy, white-matter disease and focal lesions. | Grade 1 occurred in 38% of the 936 cognitively intact participants in the 2019 normative study, and the higher-hemisphere 90th percentile was no more than 1 through age 59. Therefore a grade of 1 is not by itself evidence of neurodegenerative disease or a calibrated risk estimate. | Koedam et al. 2011, PMC3217148, Methods: grade 1 mild widening without evident gyral loss; Cotta Ramusino et al. 2019, DOI 10.1016/j.nicl.2019.101936, PMC6690662, PA frequency and age-stratified 90th percentiles. | ✓ |
| 2 | Grade 2 | Per hemisphere, grade 2 requires substantial widening of the posterior cingulate and parieto-occipital sulci together with visible loss of parietal-lobe and precuneus gyral volume. It is more than mild opening but does not yet require end-stage knife-blade atrophy. | Grade 2 may strengthen a posterior-predominant atrophy impression when it fits the cognitive phenotype, but it still does not select a test or therapy. Consider specialist cognitive evaluation and appropriately chosen biomarker assessment only from the whole clinical context; investigate focal or asymmetric mimics separately. | Higher posterior-atrophy scores were associated with Alzheimer-group membership and lower MMSE in the selected derivation sample, but grade 2 still fell within the higher-hemisphere 90th percentile for cognitively intact adults aged 60-84 in the normative cohort. It is nonspecific and not a personal probability of Alzheimer disease or decline. | Koedam et al. 2011, PMC3217148, Methods and Results: grade 2, group means and independent MMSE association; Cotta Ramusino et al. 2019, PMC6690662, age 60-84 PA 90th-percentile context; Jack et al. 2024, biological diagnostic boundary. | ✓ |
| 3 | Grade 3 | Per hemisphere, grade 3 is end-stage posterior atrophy with evident severe widening of the posterior cingulate and parieto-occipital sulci and knife-blade atrophy of the parietal lobes and precuneus. Preserve laterality, decisive plane and any focal structural confounder. | A grade-3 posterior pattern warrants clear communication and clinical correlation, but it does not itself diagnose Alzheimer disease or prescribe counseling, driving restrictions, medication, disease-modifying therapy or follow-up. Management requires the clinical syndrome, confirmed biology when relevant, contraindications and specialist judgment. | Grade 3 is the most severe morphology and is unusual relative to the reported cognitively intact age distributions, but it remains etiologically nonspecific. Do not convert it into certainty of Alzheimer pathology, dementia severity, future decline or a treatment ceiling. | Koedam et al. 2011, DOI 10.1007/s00330-011-2205-4, PMC3217148, Methods: grade 3 end-stage knife-blade definition; Cotta Ramusino et al. 2019, PMC6690662, normative distributions; Jack et al. 2024, DOI 10.1002/alz.13859, biomarker-based Alzheimer criteria. | ✓ |

### Citações por categoria
- **0**: Koedam ELGE, Lehmann M, van der Flier WM, et al.. Visual assessment of posterior atrophy: development of a MRI rating scale (2011) — https://pmc.ncbi.nlm.nih.gov/articles/PMC3217148/ · Koedam et al. 2011, DOI 10.1007/s00330-011-2205-4, PMC3217148, Methods: grade 0 landmarks, bilateral assessment, three planes and highest-plane rule; Jack et al. 2024, DOI 10.1002/alz.13859, biological Alzheimer boundary.
- **1**: Koedam ELGE, Lehmann M, van der Flier WM, et al.. Visual assessment of posterior atrophy: development of a MRI rating scale (2011) — https://pmc.ncbi.nlm.nih.gov/articles/PMC3217148/ · Koedam et al. 2011, PMC3217148, Methods: grade 1 mild widening without evident gyral loss; Cotta Ramusino et al. 2019, DOI 10.1016/j.nicl.2019.101936, PMC6690662, PA frequency and age-stratified 90th percentiles.
- **2**: Koedam ELGE, Lehmann M, van der Flier WM, et al.. Visual assessment of posterior atrophy: development of a MRI rating scale (2011) — https://pmc.ncbi.nlm.nih.gov/articles/PMC3217148/ · Koedam et al. 2011, PMC3217148, Methods and Results: grade 2, group means and independent MMSE association; Cotta Ramusino et al. 2019, PMC6690662, age 60-84 PA 90th-percentile context; Jack et al. 2024, biological diagnostic boundary.
- **3**: Koedam ELGE, Lehmann M, van der Flier WM, et al.. Visual assessment of posterior atrophy: development of a MRI rating scale (2011) — https://pmc.ncbi.nlm.nih.gov/articles/PMC3217148/ · Koedam et al. 2011, DOI 10.1007/s00330-011-2205-4, PMC3217148, Methods: grade 3 end-stage knife-blade definition; Cotta Ramusino et al. 2019, PMC6690662, normative distributions; Jack et al. 2024, DOI 10.1002/alz.13859, biomarker-based Alzheimer criteria.

## Referências cruzadas
- _fronteira compartilhada_ → [GCA — Original Pasquier cerebral atrophy regional scale](https://radcommons.laudos.ai/systems/gca-pasquier.md) — Koedam focuses on the posterior cortex; GCA gives the global atrophy impression.
- _fronteira compartilhada_ → [Scheltens MTA — Scheltens medial temporal atrophy visual rating scale](https://radcommons.laudos.ai/systems/scheltens-mta.md) — Complementary dementia visual rating scales: Koedam grades posterior/parietal atrophy, Scheltens grades medial temporal atrophy.

## Histórico de versões

| Data | Evento | Detalhe | Situação |
| --- | --- | --- | --- |
| 2019-08-01 | revised | A 936-participant cognitively intact reference study supplied age-stratified posterior-atrophy distributions. This is normative context, not a revision of the four category definitions. | confirmed |
| 2011-07-01 | published | Posterior atrophy visual rating scale published in European Radiology. | confirmed |


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> Conteúdo de referência reescrito. Confira a publicação primária vigente. Não é dispositivo médico nem substitui o julgamento clínico. O radiologista responsável pelo laudo permanece o autor e o responsável.

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