SonoAtlas / SonoTools

VascularSim

Vascular Doppler suite · carotid · renal · DVT · aortic

Carotid Doppler stenosis simulator

Live ICA stenosis grading using the SRU/ACR consensus Doppler velocity criteria. ICA PSV drives the category; EDV, ICA/CCA ratio, and B-mode plaque confirm it. Toggle symptomatic vs. asymptomatic for management, turn on pitfall flags (contralateral occlusion, tandem lesion, dense calcification, post-CEA) and see how the reading should be re-interpreted. 20 cases, 10-question quiz, .ics follow-up export, and copy-ready structured report.

Educational use only — not a medical device SRU (Grant et al. Radiology 2003) + ACR appropriateness How to use: drag ICA PSV slider, toggle B-mode + pitfalls + symptoms
Symptoms
Side
Display
▸ R reset   ▸ T teach mode   ▸ V clinician/patient wording   ▸ S toggle symptoms   ▸ 1–6 quick-pick category
Quick-pick Preset scenarios
Doppler measurements ICA + CCA
ICA peak systolic (PSV) 90cm/s
0125230400500
Primary SRU criterion. <125 = normal/<50%, 125–230 = 50–69%, >230 = ≥70%.
Teach: ICA PSV is sampled at the point of maximum narrowing, with the Doppler angle 60° (≤60° acceptable, never >60°) and the sample volume 2–3 mm, parallel to flow. Over-angling or off-axis sampling falsely elevates PSV.
ICA end-diastolic (EDV) 25cm/s
040100200
Secondary. ≥100 supports ≥70% stenosis. 40–100 seen in 50–69%.
Teach: EDV rises later than PSV as stenosis tightens. An EDV <40 with a borderline PSV suggests <50% despite a high PSV number; an EDV ≥100 is one of the most specific findings for ≥70%.
CCA PSV (for ratio) 80cm/s
3060100200
Sample 2 cm below bifurcation, same side. Ratio = ICA PSV ÷ CCA PSV.
Teach: CCA velocity is the denominator that normalizes for cardiac output, contralateral disease, and inter-patient variability. If ipsilateral CCA is itself diseased, ratio becomes unreliable.
ICA / CCA PSV ratio 1.1
0.52.04.010
Secondary. <2 = <50%, 2.0–4.0 = 50–69%, >4.0 supports ≥70%.
Teach: The ratio is most useful when PSV is borderline or when systemic factors (hypertension, aortic stenosis, contralateral occlusion) shift all velocities up or down.
B-mode plaque + lumen B-mode confirmation
Plaque (diameter reduction)
Lumen + flow
Clinical / technical pitfall flags Discordance modifiers
SRU category grid Primary + secondary criteria
Criterion
Normal
<50%
50–69%
≥70%
Near-occ
0PSVEDVbaseline
Schematic waveform: current PSV / EDV shown against baseline.
— No category
Enter ICA / CCA velocities to compute a category.
Counterfactuals What would flip the category?
Structured report Copy-ready
Auto-generated from current state
Follow-up Surveillance timing
—
Select a category to compute follow-up.
Case bank 20 cases
Quiz SRU criteria · 10 Q
Recent scenarios Last 8
No recent scenarios yet.
Pitfalls Commonly missed

Renal artery stenosis Doppler simulator

Hemodynamically significant renal artery stenosis (RAS) grading from duplex Doppler. Main renal artery PSV > 180 cm/s and renal-aortic ratio (RAR) > 3.5 are the primary direct signs; intrarenal acceleration time > 70 ms and a tardus-parvus waveform in segmental/interlobar arteries are the indirect signs that confirm flow-limiting proximal disease. Toggle accessory arteries, AAA aortic distortion, post-stent status, and kidney size to see how the reading should change. 10 cases, 10-question quiz.

Educational use only — not a medical device AIUM + vascular-lab consensus RAS criteria How to use: adjust PSV + AT, toggle tardus-parvus + pitfalls
Indication
Side
Display
▸ R reset   ▸ T teach mode   ▸ V clinician/patient wording   ▸ 1–5 quick-pick category
Quick-pick Preset scenarios
Direct Doppler — main renal artery Primary criteria
Main RA peak systolic (PSV) 120cm/s
0180300400600
Primary direct sign. >180 suggests ≥60% stenosis. >300–400 with RAR >4 favours ≥80%.
Teach: Sample the main renal artery at its origin from the aorta, angle ≤60°. Peak velocity at the point of maximum narrowing is the direct proof of an arterial stenosis. Every other number is a supporting or indirect clue.
Aortic PSV (suprarenal) 70cm/s
3070120200
Denominator for the renal-aortic ratio (RAR). Sample at the level of the SMA / suprarenal aorta, ≤60° angle.
Teach: RAR = RA PSV ÷ aortic PSV. It normalizes for cardiac output and systemic factors. Unreliable when the aorta is aneurysmal or itself stenotic — use direct PSV in those cases.
Renal / aortic ratio (RAR) 1.7
0.53.55.510
Primary secondary. >3.5 supports ≥60% stenosis; >5.5 tilts toward ≥80%.
Teach: RAR >3.5 with a high RA PSV is the most specific combined finding for ≥60% RAS. Both criteria matter — a high PSV with normal RAR may be from high cardiac output, not stenosis.
Resistive index (RI) — affected kidney 0.65
0.300.550.701.00
Intrarenal RI. <0.55 with asymmetry (Δ >0.05) supports proximal RAS. >0.80 = parenchymal disease — revascularization less likely to help.
Teach: RI = (PSV − EDV) / PSV. In flow-limiting proximal RAS, the affected side has LOW RI (dampened upstroke). In small-vessel/parenchymal disease, RI is HIGH on both sides — a marker that revascularization will likely not improve BP or GFR.
Indirect Doppler — intrarenal waveform Tardus–parvus signs
Acceleration time (AT) 55ms
3070100200
Time from waveform onset to first systolic peak, in segmental / interlobar artery. >70 ms = tardus; >100 ms strongly abnormal.
Teach: AT is the most important indirect sign. It becomes prolonged downstream of a flow-limiting proximal stenosis because blood has to accelerate through a narrower channel. It is especially useful when the main RA cannot be insonated (bowel gas, deep vessel, accessory artery).
Acceleration index (AI) 450cm/s²
50300500800
Slope of the systolic upstroke. <300 cm/s² = parvus; supports the AT finding.
Teach: AI = Δvelocity ÷ AT over the upstroke. Low AI is the "parvus" in "tardus–parvus" — not just late but also weak. Both components together are much more specific than either alone.
Intrarenal waveform pattern
Kidney size (affected side)
Clinical / technical pitfall flags Discordance modifiers
RAS category grid Direct + indirect criteria
Criterion
Normal
Borderline
Significant
Severe
0PSVATbaseline
Schematic intrarenal waveform: AT marks the upstroke.
— No category
Enter renal + aortic velocities to compute a category.
Counterfactuals What would flip the category?
Structured report Copy-ready
Auto-generated from current state
Follow-up Surveillance timing
—
Select a category to compute follow-up.
Case bank 10 cases
Quiz RAS criteria · 10 Q
Recent scenarios Last 8
No recent scenarios yet.
Pitfalls Commonly missed

DVT compression ultrasound simulator

Lower-extremity venous compression ultrasound — the cornerstone test for suspected deep venous thrombosis. Non-compressibility of the vein is the primary criterion (a normal vein collapses completely under direct transducer pressure). Echogenicity of the thrombus distinguishes acute (anechoic, dilated) from chronic (echogenic, retracted, collaterals). Augmentation and colour/spectral Doppler are secondary. Combine with Wells score for pre-test probability. 10 cases, 10-question quiz, structured report, .ics follow-up.

Educational use only — not a medical device ACR / AIUM venous compression protocol How to use: set compressibility + echogenicity + Wells score
Leg
Presentation
Display
▸ R reset   ▸ T teach mode   ▸ V clinician/patient wording   ▸ 1–5 quick-pick category
Quick-pick Preset scenarios
Venous segment Compression point
Segment being evaluated
Teach: Two-point compression covers CFV + popliteal. Extended (whole-leg) adds SFV + calf veins. Isolated distal (calf) DVT has lower PE risk but can propagate — follow-up scan at 5–7 days if not anticoagulated.
Compression ultrasound signs Primary criterion
Compressibility Full
Direct transducer pressure should fully collapse a normal vein. Incompressibility is the primary criterion for DVT.
Teach: Apply enough pressure to deform the adjacent artery slightly. If the vein does not fully coapt, intraluminal thrombus is present. This single manoeuvre has high sensitivity and specificity for proximal DVT.
Thrombus echogenicity None
Anechoic / hypoechoic + dilated, poorly-echogenic vein = acute. Echogenic, retracted wall + collaterals = chronic.
Teach: Fresh clot is soft and nearly anechoic (1–7 days). As it organises it becomes heterogeneously echoic (1–6 weeks). Chronic post-thrombotic change shows echogenic webs, a contracted vein, and visible collaterals — these patients do not need re-anticoagulation.
Vein diameter vs adjacent artery 1.0× artery
0.41.01.62.5
Acute thrombus dilates the vein — ratio >1.5× paired artery. Chronic thrombus contracts it — ratio <0.8×.
Teach: Acute DVT distends the vein because the clot holds it open. Chronic disease retracts it through fibrous replacement. The vein-to-artery diameter ratio at the same level is a fast way to read this.
Augmentation / spontaneous flow Normal
Calf squeeze should produce a brisk augmentation signal. Absent flow in a large vein suggests occlusive thrombus between the probe and the squeeze.
Teach: Spectral / colour flow and augmentation are ancillary. Compression is primary. In technically difficult exams (obesity, cast, gross oedema), augmentation and spontaneous phasicity become more important.
Thrombus extent
Collateral veins
Wells score Pre-test probability
Wells DVT score 0
-2029
< 1 = unlikely (use D-dimer); ≥ 2 = likely (ultrasound mandatory).
Teach: Wells DVT items (each 1 point): active cancer, paralysis/immobility, recent surgery or bedrest >3d, localised tenderness, entire leg swollen, calf >3 cm asymmetry, pitting oedema, collaterals, previous DVT. Subtract 2 if an alternative diagnosis is more likely.
Clinical / technical pitfalls Discordance modifiers
DVT category grid Compression + echogenicity + Wells
Criterion
No DVT
Acute DVT
Chronic
Mimic
ProbeVeinArterycompress
Schematic: compressibility of the vein against the adjacent artery.
— No category
Set compressibility and echogenicity to compute a category.
Counterfactuals What would flip the category?
Structured report Copy-ready
Auto-generated from current state
Follow-up Surveillance timing
—
Select a category to compute follow-up.
Case bank 10 cases
Quiz DVT criteria · 10 Q
Recent scenarios Last 8
No recent scenarios yet.
Pitfalls Commonly missed

Aorta AAA · dissection · mesenteric · EVAR simulator

Four aortic indications bundled into one tool. AAA screening uses outer-to-outer anteroposterior diameter and SVS 2018 surveillance intervals. Dissection uses a true-lumen/false-lumen sign with flow direction. Mesenteric ischemia uses celiac >200 cm/s and SMA >275 cm/s fasting (Cleveland Clinic). EVAR surveillance classifies endoleaks I–V. Switch between indications with the top selector. 10 cases per indication concept, 10-question quiz, structured report.

Educational use only — not a medical device SVS 2018 AAA surveillance + Cleveland mesenteric How to use: pick indication at top, then enter measurements
Indication
Display
▸ R reset   ▸ T teach mode   ▸ V clinician/patient wording   ▸ 1–5 quick-pick
Quick-pick Preset scenarios
Aortic measurements Primary data
Max infrarenal AAA diameter (outer-to-outer AP) 2.2cm
1.53.05.510
SVS 2018: <3 cm normal · 3.0–3.9 q3y · 4.0–4.9 annual · 5.0–5.4 q6mo · ≥5.5 cm (men) or ≥5.0 cm (women) repair.
Teach: Always measure outer-to-outer wall on the true anteroposterior axis in transverse. Calliper placement on the intima undersizes by 2–4 mm. Reproducibility matters — a 10% difference between scans is meaningful.
Growth rate (since last scan) 0mm/yr
051020
>10 mm/year triggers repair regardless of absolute size.
Teach: Rapid expansion is independently associated with rupture. SVS threshold is 0.5 cm in 6 months or 1.0 cm in 12 months. Even at 4.5 cm, a rapidly-growing AAA should be repaired.
Celiac PSV (fasting) 140cm/s
60200350500
Celiac PSV >200 cm/s = ≥70% stenosis (Cleveland Clinic).
Teach: The celiac is first to show respiratory variation from median arcuate ligament compression — PSV rises on expiration and falls on inspiration. True atherosclerotic stenosis stays elevated through the respiratory cycle.
SMA PSV (fasting) 160cm/s
60275400600
SMA PSV >275 cm/s fasting = ≥70% stenosis (Cleveland Clinic). Postprandial >400 cm/s is abnormal.
Teach: SMA is the most consistent mesenteric vessel — stenosis here drives symptoms. High-grade stenosis of both celiac and SMA (plus a preserved IMA collateralising from the inferior mesenteric arcade) is the classic chronic-mesenteric-ischemia picture.
Indication-specific features Dissection / EVAR / mimics
Dissection flap + true/false lumen
EVAR endoleak
Symptoms / exam
Clinical / technical pitfalls Discordance modifiers
Aortic category grid By indication
Criterion
Normal
Mild
Moderate
Severe
035.5cm
Schematic: aortic cross-section with measured AP diameter.
— No category
Select an indication and set values to compute a category.
Counterfactuals What would flip the category?
Structured report Copy-ready
Auto-generated from current state
Follow-up SVS 2018 surveillance
—
Select a category to compute follow-up.
Case bank 10 cases
Quiz Aortic duplex · 10 Q
Recent scenarios Last 8
No recent scenarios yet.
Pitfalls Commonly missed

Dialysis access AVF / AVG duplex simulator

Hemodialysis access surveillance by duplex Doppler. Volume flow (ml/min) is the single most important maturation and surveillance parameter: AVF <600 fails, >600 mature, >2000 considered high-flow with cardiac risk. Peak-velocity ratio > 3× at the arterial anastomosis or venous outflow is the standard for hemodynamically significant stenosis. Detects steal, pseudoaneurysm, and thrombosis. 10 cases, 10-question quiz.

Educational use only — not a medical device KDOQI 2019 access surveillance How to use: set Qa + PSV ratio, toggle AVF/AVG + pitfalls
Access type
Location
Display
▸ R reset   ▸ T teach mode   ▸ V clinician/patient wording   ▸ 1–6 quick-pick
Quick-pick Preset scenarios
Volume-flow + velocity measurements Primary criteria
Volume flow (brachial artery or access mid-vessel) 1000ml/min
060020003500
AVF mature >600 ml/min (ideally >800). Dysfunctional <600. High-flow >2000.
Teach: Measure time-averaged mean velocity × cross-sectional area in the brachial artery (proxies total access flow) or a straight, non-aneurysmal segment of the access itself. >20% drop between scans is a surveillance threshold even above 600 ml/min.
Anastomotic PSV 300cm/s
50300500800
Normal arterial-anastomotic PSV is 200–400 cm/s — elevated PSV alone does not equal stenosis.
Teach: Velocities at the arterial anastomosis are naturally very high. Use the PSV RATIO between the stenosis and the adjacent upstream segment — not the absolute PSV — for a stenosis call.
Peak-velocity ratio across narrowest segment 1.5×
1238
>2× suggests stenosis; >3× = hemodynamically significant ≥50% stenosis (surgical / endovascular referral).
Teach: The SVS/KDOQI standard: PSV at the narrowest point divided by PSV 2 cm upstream. >3.0 = significant stenosis. It normalises for the wide variability in baseline flow between accesses.
Venous outflow PSV 200cm/s
30200400700
Focal outflow PSV >400 cm/s or ratio >3× points to venous-outflow stenosis — the commonest surveillance lesion.
Teach: Venous neo-intimal hyperplasia at the cannulation zone and proximal draining veins is the dominant late-failure mode. Angio-plasty here restores function, and surveillance catches it before full thrombosis.
Complications / ancillary findings Clinical integration
Access status
Steal syndrome
Pseudoaneurysm / aneurysm
Clinical / technical pitfalls Discordance modifiers
Access category grid Flow + ratio + clinical
Criterion
Mature
Low flow
Stenosis
Thrombosed
inflowanastoutflowQa
Schematic: pulsatile low-resistance flow along a mature AVF.
— No category
Set flow, ratio, and status to compute a category.
Counterfactuals What would flip the category?
Structured report Copy-ready
Auto-generated from current state
Follow-up Surveillance timing
—
Select a category to compute follow-up.
Case bank 10 cases
Quiz Dialysis access · 10 Q
Recent scenarios Last 8
No recent scenarios yet.
Pitfalls Commonly missed

Peripheral arterial ABI · segmental · duplex simulator

Peripheral arterial disease (PAD) assessment by ABI, segmental pressures, and duplex Doppler. ABI 0.90–1.40 is normal; 0.70–0.90 mild, 0.40–0.70 moderate, <0.40 severe / critical limb ischemia. ABI >1.40 is falsely elevated from medial calcification — use the toe-brachial index (TBI) instead. PSV ratio >2× across a narrowing = ≥50% stenosis; biphasic → monophasic waveform degradation tracks disease severity. 10 cases, 10-question quiz.

Educational use only — not a medical device AHA / ACC PAD guidelines How to use: drag ABI (+ TBI if calcified), set waveform + pitfalls
Side
Presentation
Display
▸ R reset   ▸ T teach mode   ▸ V clinician/patient wording   ▸ 1–5 quick-pick
Quick-pick Preset scenarios
Physiologic testing Primary criteria
Ankle-brachial index (ABI) 1.00
00.400.901.401.80
Normal 0.90–1.40 · 0.70–0.90 mild · 0.40–0.70 mod · <0.40 severe · >1.40 non-compressible → use TBI.
Teach: ABI = higher ankle pressure (DP or PT) / higher brachial pressure. Measured with Doppler. Single most important screening test for PAD. Exercise ABI with >20% drop is positive when resting is borderline.
Toe-brachial index (TBI) 0.75
00.400.701.0
Used when ABI is non-compressible (>1.40). Normal TBI >0.70; <0.70 abnormal; <0.30 critical ischemia.
Teach: Digital arteries resist Mönckeberg calcification. In diabetics and CKD patients with falsely normal ABIs, TBI and pulse-volume recordings become the reference test.
Segmental level with abnormal pressure drop —
>20 mmHg pressure drop between cuffs localises the lesion.
Teach: Pressure drops >20 mmHg between sequential cuffs (high thigh → above-knee → below-knee → ankle) localise the disease level. Multilevel disease halves the likelihood of success from a single intervention.
Peak-velocity ratio at narrowest segment 1.5×
1248
>2× = ≥50% stenosis · >4× = ≥75% · no flow = occlusion.
Teach: Duplex PSV ratio replaces ABI at the segment level. Combined with waveform shape (triphasic / biphasic / monophasic), this maps directly onto intervention planning — endovascular vs. bypass, proximal vs. distal.
Waveform shape at tibial level
Wound / tissue loss
Clinical / technical pitfalls Discordance modifiers
PAD category grid ABI + duplex + clinical
Criterion
Normal
Mild
Moderate
Severe
0triphasicmonoabsent
Schematic tibial arterial waveform — triphasic / biphasic / monophasic / absent.
— No category
Enter ABI and waveform to compute a category.
Counterfactuals What would flip the category?
Structured report Copy-ready
Auto-generated from current state
Follow-up Surveillance timing
—
Select a category to compute follow-up.
Case bank 10 cases
Quiz PAD / ABI · 10 Q
Recent scenarios Last 8
No recent scenarios yet.
Pitfalls Commonly missed
VascularSim · Part of SonoTools on SonoAtlas · Educational — not a medical device · Carotid criteria from Grant EG et al. Radiology 2003 (SRU consensus); renal criteria from AIUM + vascular-lab consensus.

CIMT Carotid intima-media thickness

Cardiovascular-risk screening via far-wall common carotid intima-media thickness. This tab does not grade stenosis — use the Carotid tab for that. Here you enter patient age, sex, measured mean far-wall CCA IMT (in mm), and any focal plaque thickness; the engine looks up the Stein / ASE 2008 p50 / p75 reference for that age-sex and categorises you as favourable (< p50), average (p50–p75), high percentile (≥ p75), absolute elevation (≥ 1.0 mm, independent of age), or focal plaque (≥ 1.5 mm — reclassified out of IMT per Mannheim). ESH / ESC flag: IMT ≥ 0.9 mm counts as subclinical hypertensive organ damage. 10 cases spanning ages 30–70 across both sexes, 5-question quiz.

Educational use only — not a medical device Mannheim + Stein (ASE 2008) + ESH 2023 How to use: set Age + Sex, drag CIMT slider, read category
Measurements Demographics
Age60
SexM
CIMT (mm)0.70
Focal plaque (mm)0.00
— No category
Enter age, sex, and measured CIMT to compute a category.
Presets
Cases 10
Quiz 5Q

Venous Reflux CEAP / chronic venous insufficiency

Lower-extremity venous reflux duplex per AVF / SVS / AIUM consensus. This tab is the reflux counterpart to the DVT tab (which handles acute thrombosis). Here you measure reflux time in seconds per segment — deep (CFV, FV, popliteal, tibial), superficial (GSV, SSV, accessory saphenous), and perforators (thigh, calf) — after a distal augmentation / Valsalva. Pathologic thresholds: deep > 1.0 s, superficial > 0.5 s, perforator outward > 0.5 s. The engine weighs how many deep vs. superficial vs. perforator segments are abnormal and routes to seven categories — normal, mild / moderate superficial, perforator incompetence, mild / severe deep, or mixed deep-superficial disease — each with CEAP-aligned management. 10 cases, 5-question quiz.

Educational use only — not a medical device SVS/AVF CPG 2011 + CEAP 2020 + AIUM venous duplex How to use: drag each segment's reflux-time slider (in seconds)
Reflux times (s) Deep >1.0, Sup >0.5
CFV
FV
Popliteal
Tibial
GSV
SSV
Accessory
Thigh perf
Calf perf
— No category
Enter segment reflux times to compute a category.
Presets
Cases 10
Quiz 5Q

Hepatic / Portal Portal hypertension duplex

Portal-hypertension and hepatic-vein duplex. Use this tab to integrate four abdominal duplex findings — hepatic vein waveform (triphasic / biphasic / monophasic), portal vein velocity (normal 15–40 cm/s), portal vein direction (hepatopetal / to-and-fro / hepatofugal), portal vein diameter, and spleen length (≥ 11 cm = splenomegaly) — plus checkboxes for ascites and recanalised paraumbilical vein. The engine routes: normal → early portal HTN (biphasic HV, PV still hepatopetal) → established portal HTN (biphasic HV + slow PV + splenomegaly) → cirrhosis with advanced portal HTN (reversed PV + monophasic HV + splenomegaly) → Budd-Chiari suspect (monophasic HV but patent PV) → acute PVT (absent PV flow) → chronic PVT / cavernous transformation. 10 cases (normal, compensated cirrhosis, advanced portal HTN with hepatofugal PV, Budd-Chiari, right-heart-failure mimic, post-TIPS, acute PVT, chronic cavernous PVT, PV aneurysm, early cirrhosis), 5-question quiz.

Educational use only — not a medical device Baveno VII + AIUM hepatic Doppler + Valla 2018 (Budd-Chiari) How to use: set HV waveform + PV velocity/direction/diameter + spleen + ascites
Hepatic + Portal Fasting
HV waveformtriphasic
PV velocity (cm/s)20
PV diameter (mm)13
PV directionhepatopetal
Spleen (cm)10
— No category
Enter HV waveform and PV parameters to compute a category.
Presets
Cases 10
Quiz 5Q