{"doi":"10.3174/ajnr.a7190","title":"A Volumetric Metric for Monitoring Intracranial Aneurysms: Repeatability and Growth Criteria in a Longitudinal MR Imaging Study","abstract":"BACKGROUND AND PURPOSE: The reliability of contrast-enhanced MRA in monitoring serial volumetric changes of unruptured intracranial aneurysms has not been established. We aimed to determine the coefficient of variance of contrast-enhanced MRA in measuring aneurysm volumes, thus establishing criteria for aneurysm growth and permitting identification of variables predictive of growth. MATERIALS AND METHODS: Aneurysm volumes were measured from serial contrast-enhanced MRA studies of patients with untreated intracranial aneurysms who underwent >2 sequential MR imaging evaluations. After coregistering all sequential studies in 3D space for each aneurysm and signal intensity normalization, aneurysm volume was determined across all time points. A linear mixed effects model was built to estimate the coefficient of variance of the measurement as well as to determine predictive variables. Growth was defined as relative growth exceeding 2 times the measurement coefficient of variance (sudden growth, as 4 times the coefficient of variance). RESULTS: A total of 95 patients with 112 aneurysms were included (5.9 scans during 4.0 years on average, 616 scan measurements in total). The coefficient of variance was 5.5% of the aneurysm volume, and the relative growth rate was dependent on the location: anterior cerebral artery, 4.52% per year; vertebral artery, 2.46% per year; middle cerebral artery, 2.74% per year; basilar artery, 2.36% per year; internal carotid artery, 1.14% per year. Thirty-six of 112 (32%) aneurysms were characterized as growing, and 11/36 of them had an episode of sudden growth. CONCLUSIONS: Volume measurement of unruptured intracranial aneurysms by contrast-enhanced MRA seems a reliable metric for tracking the growth trajectory of aneurysms. Furthermore, the aneurysm growth rate differs among different locations.","journal":"American Journal of Neuroradiology","year":2021,"id":178517,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":19,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9562,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2021-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":724305,"name":"Henrik Haraldsson","orcid":"0000-0003-2363-2994","position":1,"is_corresponding":false},{"id":294162,"name":"Yuting Wang","orcid":"0000-0002-1443-2643","position":2,"is_corresponding":false},{"id":700912,"name":"Evan Kao","orcid":"0000-0003-2975-3690","position":3,"is_corresponding":false},{"id":580622,"name":"Megan Ballweber","orcid":"0000-0002-6770-9984","position":4,"is_corresponding":false},{"id":330930,"name":"Alastair J. Martin","orcid":"0000-0002-7963-4000","position":5,"is_corresponding":false},{"id":19019,"name":"Charles E. McCulloch","orcid":"0000-0002-1279-6179","position":6,"is_corresponding":false},{"id":724306,"name":"Farshid Faraji","orcid":"0000-0003-3218-1347","position":7,"is_corresponding":false},{"id":294164,"name":"David Saloner","orcid":"0000-0002-6989-8547","position":8,"is_corresponding":false},{"id":725081,"name":"for the UCSF Intracranial Aneurysm Monitoring Group","orcid":null,"position":9,"is_corresponding":false},{"id":514941,"name":"Xinke Liu","orcid":"0000-0003-3918-0814","position":0,"is_corresponding":true}],"reference_count":31,"raw_metadata":null,"created_at":"2026-07-18T23:47:40.592580Z","pmid":"34167960","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}