Literature-bounded interpretation

AAA measurement context calculator

Compare entered imaging and plasma measurements with published human AAA study summaries. This tool describes measurement context—it does not estimate rupture risk.

Abdominal aortic aneurysm onlyGuideline context—not a rupture scorePatient-level research context

AAA-only scope

When to use

Use for

Adult abdominal aortic aneurysm research.
Hospital-reported maximum AAA diameter in mm.
Matched scan-day plasma D-dimer in mg/L FEU.
Source-bounded descriptive comparison with published cohorts.

Do not use for

Rupture or growth prediction, treatment, or surveillance decisions.
AAA screening or diagnosis.
Thoracic, intracranial, or other non-abdominal aneurysms.
Replacing 4D-CTA registration, motion qualification, or uncertainty QC.

Enter values

Patient measurements

Enter values available from the hospital record. Age, smoking, and symptoms provide guideline context; ILT and total-sac volumes are not treated as patient inputs.

Maximum AAA diameter

Use the maximum outer-to-outer diameter reported from the patient’s clinical imaging record.

Age

years

Age is displayed as clinical context only. It does not contribute points or generate a rupture probability.

Smoking status

Smoking is established AAA context. No probability is assigned from this entry.

New abdominal or back pain attributed to the AAA

Symptoms affect clinical urgency but are not combined with the research measurements as a numerical score.

Selected automatically from AAA sizeAAA <55 mm published context

Published median sac volume used for the sensitivity scenario: 102.5 mL.

Plasma D-dimer

mg/L FEU

Use the matched scan-day hospital value in mg/L FEU. It moves the bounded ILT sensitivity scenario within the selected group’s published IQR.

See context

Patient result

Hospital-reported AAA size50.0 mmautomatically uses the AAA <55 mm literature context50.0 mm → <55 mm

D-dimer2.16 mg/L FEU

Within this study group’s IQR

Published size-group median: 2.16 mg/L FEU

Bounded ILT scenario≈ 57.2 mL

Derived rILT scenario: 55.8%

57.2 mL ÷ 102.5 mL sac. Sensitivity scenario—not a patient measurement or regression prediction.

Guideline contextSurveillance context

The entered diameter is below 55 mm; surveillance timing depends on the exact diameter and clinical context.

Age 72 years · former smoker · no new AAA-attributable pain entered. This is a structured summary, not a validated risk score or treatment recommendation.

What this means

Diameter selects the published AAA <55 mm context. Within that context, the entered D-dimer’s IQR position is mapped to the same position within the reported ILT-volume IQR. This transparent sensitivity assumption drives the 3D thrombus display; it is not a validated D-dimer-to-ILT conversion.

No rupture probability is calculated.The clinical-context summary remains separate from the exploratory imaging and plasma measurements.

P13 indexed phase geometry

4D-CTA wall–thrombus–lumen phase sweep

Follow the six supplied P13 configurations with the same displacement field driving the exterior wall, intraluminal thrombus, and lumen. Color shows full-vector displacement magnitude from CT0.

De-identified P136 indexed CTA frames · RAS coordinates

Movement displayTrue 1× geometric displacement

Show CT0 reference mesh

Visible layers

Wall motion mapILT boundaryLumen boundary

Full-vector |u| from CT00.00 mm median0.00 mm 90th percentileField-derived readout · geometry at 1×

Displacement magnitude |u|

00.6≥1.2 mm

Drag to rotate · Scroll to zoom

Integrated 3D configurationLoading P13 phase geometry…

Inspect between supplied frames0.00CT0CT5

P13 displacement profileFull-vector |u| from CT0

Current position 0.00

Data-faithful playback: the source article identifies P13 CT0 as the systolic configuration and CT5 as the diastolic configuration based on expert visual inspection; CT1–CT4 preserve indexed acquisition order but have no published percentage labels. The viewer interpolates between supplied fields, then reverses them only as a clearly labeled display return. It does not reconstruct missing ECG timing, pressure, flow, or an uncertainty-qualified U_50,A result.

Hospital AAA size50.0 mm

D-dimer2.16 mg/L FEU

Scenario ILT volume≈ 57.2 mL

Scenario relative ILT≈ 55.8%

How the two hospital inputs are used

Reported maximum diameter scales only the source model’s transverse width and selects the <55 mm cohort; P13 length and morphology remain fixed because diameter alone cannot reconstruct them. D-dimer’s position within that group’s published IQR is mapped to the same position within its ILT-volume IQR; rILT is then calculated as ILT volume divided by the group-median sac volume. Source reference: 134.6 mL enclosed sac and 70.9 mL ILT.

The resulting sensitivity scenario changes lumen size and visible thrombus thickness. It is not a fitted D-dimer-to-ILT equation or patient-specific reconstruction. Cardiac deformation remains the P13 trajectory.

Observed

Hospital-reported diameter and scan-day plasma D-dimer.

Source data

P13 exterior wall, ILT, lumen, and CT0-to-phase registration fields.

Displayed

Continuous interpolation between the six supplied indexed configurations.

Scenario

Diameter scaling and the bounded D-dimer-to-ILT IQR mapping; neither reconstructs patient anatomy or mechanics.

Visible change, bounded claim.D-dimer drives only the stated literature-IQR sensitivity scenario. It does not change the P13 motion field or establish patient-specific ILT, stress, strain, stiffness, flow, SII, or RSII.

Source: de-identified P13 4D-CTA and paired surface files from the supplied open 20-patient AAA dataset. The viewer retains the full exterior-wall, ILT-interface, and lumen-interface triangle sets; phase offsets are computed in physical image coordinates. Dataset and acquisition details · Registration-based kinematics method.

Visual comparison

Linked literature-bounded scenario

The D-dimer plot shows the hospital value. The ILT plot shows the synchronized sensitivity scenario used to change the visible thrombus.

Published IQRMedianPatient value

Plasma D-dimerMedian and interquartile range

Absolute ILT volumeMedian and interquartile range

Fan et al., 2020. The within-group IQR-position mapping is an explicit sensitivity assumption for visualization, not a fitted regression, patient prediction, or clinical reference interval.

Interpret carefully

Pearls & pitfalls

Pearls

AAA diameter automatically selects the matching published size context.
The D-dimer graph shows the hospital value beside published cohort summaries.
The visible thrombus and derived relative ILT update with the bounded ILT sensitivity scenario.

Pitfalls

D-dimer is systemic and nonspecific; the IQR mapping is a visualization assumption, not a patient-specific conversion.
Lower or higher wall motion alone does not establish flow, stiffness, wall strength, or rupture risk.
Published u₉₉ and proposed U_50,A are different motion endpoints and are not interchangeable.

Purpose

Why use this calculator?

Use hospital values

Enter only reported maximum AAA diameter and scan-day D-dimer.

See a bounded scenario

Map the D-dimer IQR position to the published ILT IQR and update the 3D thrombus.

Keep claims bounded

Separate descriptive measurement context from prediction, causation, and clinical decision-making.

Plain-language reference

Definitions

Relative ILT

Absolute ILT volume divided by total aneurysm-sac volume, multiplied by 100. It describes CTA-visible thrombus occupancy of the bounded sac.

Interquartile range (IQR)

The middle 50% of values reported in a study group. It is a descriptive study range, not a normal range or clinical threshold.

Plasma D-dimer

A systemic fibrin-turnover measurement. It is nonspecific and cannot be attributed only to AAA thrombus.

4D-CTA motion endpoint

Registration-derived wall displacement across ECG-gated CTA phases. U_50,A must be qualified separately and does not measure stiffness, strength, flow, or rupture risk.

Research workflow

Research next steps

1
Match the records
Confirm the same patient, scan day, sample timing, and units.
2
Check segmentation
Review CTA boundaries and confirm total-sac volume is not smaller than ILT volume.
3
Qualify motion separately
Apply registration and uncertainty gates before interpreting U_50,A.
4
Analyze at patient level
Report effect estimates, uncertainty, and null findings without converting associations into clinical risk.

Evidence and measurement notes

Published cohort context

Fan et al., Life Sciences (2020), n=181; D-dimer and CTA were assessed within fewer than 3 days.

View the Fan et al. study

Human 4D-CTA precedent

Jamshidian et al., Journal of Biomechanics (2025), n=10; published u₉₉ range 0.53–1.13 mm.

View the Jamshidian et al. study

Open 4D-CTA example data

A 2026 open dataset describes ECG-gated patient AAA volumes, wall and ILT surface models, and cardiac-phase frames.

View the open dataset paper

Research boundary

Patient is the statistical unit. Values support descriptive, uncertainty-qualified association testing—not a learned risk model.

Clinical-context source

SVS guidance supports diameter-based surveillance, prompt evaluation of attributable abdominal or back pain, and smoking cessation. These factors are displayed without a combined probability.

View the SVS AAA guidance