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✦ The Only Dedicated VI Registry Prep Platform
Pass the VI Registry. The first time.
Built by VI techs. Every question sourced from ARRT® content specs, SIR guidelines, and ACR clinical standards. Not a textbook. A pass machine.
778
Questions
160
Mock Exam
5
Categories
100%
ARRT Aligned
No credit card until launch · Works on any device · Progress saves automatically
ARRT® Content Specifications
SIR Consensus Guidelines 2019
ACR Manual on Contrast Media 2024
NCRP Report 168
AASLD Guidelines 2021
Updated 2026
Everything you need. Nothing you don't.
Other prep products give you PDFs and static flashcards. VIRPrep gives you an adaptive engine built for how the registry actually tests.
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Mock Registry Exam
160 questions at exact ARRT® proportions. Timed mode runs at 3h 30m — the real exam clock. Auto-submits when time expires.
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Smart Spaced Repetition
SM-2 algorithm tracks every question you've seen. Surfaces the ones you keep missing at exactly the right time.
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Performance Analytics
Registry readiness score, per-category breakdown, trend chart, strengths vs. focus areas. Know exactly where you stand.
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Complete Study Guide
All 5 ARRT content areas. Anticoagulation tables, contrast protocols, vascular anatomy, exam traps, clinical scenarios. All in one place.
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Flashcard Deck
Active recall from every high-yield topic. Flip to reveal, mark as learned, filter by category. Works on your phone during breaks.
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Question Review
After every quiz, review every question — what you got right, what you missed, and why. The explanation alone is worth the price.
Built to the exact ARRT® blueprint.
The VI Registry has 160 scored questions across 5 content areas. VIRPrep mirrors those proportions exactly — so you study what's actually tested.
22
Patient Care
14% of exam
26
Image Production
16% of exam
42
Vascular Diagnostic
26% of exam
42
Vascular Interventional
26% of exam
28
Nonvascular
18% of exam
The honest comparison.
We looked at every VI prep product. Here's what we found.
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ExamEdge
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Dedicated VI Registry questions
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Full study guide (all 5 areas)
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Timed mock exam (3h 30m)
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$99/year
$174 (20 tests only)
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One price. Everything included.
Less than $2 a week. Less than your coffee the morning of the exam.
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$99
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✓ 778 registry-aligned practice questions
✓ Full mock exam at exact ARRT® proportions
✓ Timed mock — 3h 30m auto-submit
✓ Complete study guide — all 5 content areas
✓ Spaced repetition & smart review
✓ Performance analytics & progress tracking
✓ Flashcard deck & quick reference
✓ Works on desktop, tablet, and phone
✓ Updated continuously as guidelines change
Currently in private beta — early access pricing. Launch price may increase.
Frequently asked questions.
Is VIRPrep aligned with the current ARRT® VI exam?+
Yes. Every question is mapped to the current ARRT® Vascular-Interventional Radiography content specifications. Clinical values, drug doses, and procedural guidelines are updated to reflect current standards — SIR 2019, ACR 2024, AASLD 2021, and NCRP Report 168.
Does the exam have images or diagrams?+
No — the ARRT® VI registry exam is entirely text-based. No vessel identification from images, no diagrams. VIRPrep matches that format exactly. Every question is a clinical vignette or knowledge recall in text form.
How is VIRPrep different from a textbook?+
Textbooks are written for physicians and cover far more than the registry tests. VIRPrep is built specifically around what ARRT® actually asks — exam traps, clinical scenarios, the exact numbers you need to know. Active recall and spaced repetition are proven to outperform passive reading by a significant margin.
Does my progress save if I close the app?+
Yes. Your scores, bookmarks, spaced repetition data, and session history all save automatically — both locally and to our server. Pick up exactly where you left off on any device.
When does billing start?+
VIRPrep is currently in private beta. If you received an access code, you can use the app now. Full public launch with billing is coming soon. Early beta users will receive a discounted rate at launch.
What is the refund policy?+
We offer a 7-day money-back guarantee after launch. If VIRPrep isn't right for you, contact us within 7 days of purchase for a full refund — no questions asked.
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Content Areas
22 Questions · 14% of Exam
Patient Care
Patient care is the highest-stakes section for clinical judgment. Expect questions on preprocedural assessment, contrast reactions, anticoagulation, pharmacology, and emergency management. Know the why — not just drug names and doses.
Why High-Yield
This section tests clinical decision-making in real IR scenarios. The exam loves questions where you must choose between similar drugs, recognize when a patient is deteriorating, or know which lab value to check before starting a procedure. Rote memorization fails here — pattern recognition wins.
O&sub2;, IV fluids; diphenhydramine IV; epi if progressing
Anaphylaxis
Bronchospasm, laryngeal edema, BP collapse, HR ↑
Epinephrine FIRST — 0.3mg IM (1:1,000) lateral thigh
Vasovagal
Hypotension + bradycardia, diaphoresis, pallor
Atropine 0.6–1mg IV; elevate legs; fluids
Critical distinction: Anaphylaxis = tachycardia. Vasovagal = bradycardia. The heart rate tells you which drug to grab first. Epinephrine for anaphylaxis. Atropine for vasovagal. The exam will flip them.
Prior reaction risk multiplier: ~5× increased risk (NOT 10×) — ACR 2024. Premedication protocol: methylprednisolone 32mg PO at 12h and 2h before contrast.
Exam Trap: SpO&sub2; of 97% does NOT mean breathing is adequate — capnography can show apnea while SpO&sub2; still reads normal. Flat EtCO&sub2; = act immediately.
Paracentesis & thoracentesis: LOW risk — no INR correction
Dabigatran reversal: idarucizumab | Factor Xa reversal: andexanet alfa
Urgent warfarin reversal: 4F-PCC first, FFP if PCC unavailable
26 Questions · 16% of Exam
Image Production
Image production tests your understanding of fluoroscopy physics, radiation safety, DSA technique, and equipment operation. The exam rewards techs who know why dose increases, not just which button to press.
Why High-Yield
This section has predictable, testable numbers (dose thresholds, scatter geometry, ALARA principles). If you know the 5 Gy Ka,r notification threshold, the 15 Gy tissue injury threshold, and the geometry of scatter radiation — you will answer most questions correctly. DSA artifact causes are also heavily tested.
Radiation Dose — NCRP Thresholds
Threshold
Value
Action Required
Source
SRDL notification
5 Gy Ka,r
Notify referring physician; follow-up at 30 & 60 days
NCRP Report 168
TJC Sentinel Event
15 Gy PSD
Report as sentinel event; skin injury likely
Joint Commission
Deterministic threshold
2 Gy PSD
Temporary erythema possible
NCRP 116
Permanent epilation
7 Gy PSD
Permanent hair loss possible
NCRP 116
Annual occupational limit
50 mSv/yr
Whole body; monitored with dosimeter
NCRP 116
Cumulative lifetime limit
10 mSv × age
Ongoing monitoring
NCRP 116
Fluoroscopy — ALARA Dose Reduction
Dose Reduction Techniques
Last image hold (LIH) — zero radiation, shows last frame
Pulsed fluoroscopy — reduces dose vs continuous
Collimation — reduces scatter and dose to patient
Maximum SID (source-to-image distance) — reduces dose
Minimum OID (object-to-image distance) — reduces magnification artifact
Remove grid for small patients — reduces dose
Low dose or pediatric mode
Dose Increase Factors
Smaller FOV (field of view) — MORE dose (AEC compensates)
Rule: Tube above = scatter down = safer. Tube below = scatter up toward staff. For lateral projections, the operator closest to the tube gets the most scatter.
DSA — Digital Subtraction Angiography
Issue
Cause
Fix
Misregistration artifact
Patient movement between mask and fill
Reacquire mask; breath hold coaching
Motion blur
High frame rate needed for fast vessels
Increase frames/sec (cardiac DSA)
Road mapping error
Patient moved after road map acquired
Re-acquire road map
Pixel shifting
Small misregistration; bowel gas movement
Re-mask or reposition
DSA principle: Mask image (no contrast) is subtracted from live image (with contrast), leaving only the vessel. Any movement between mask and fill = misregistration = artifact.
Hydrodissection — Critical Drug Safety
D5W ONLY for RFA hydrodissection. Normal saline conducts electrical current and can cause inadvertent tissue damage. This is a common safety question. D5W = electrically inert = safe to use as a thermal/electrical barrier.
Exam Traps — Image Production
Trap: Smaller FOV = less doseFALSE. Smaller FOV = MORE dose (AEC increases technique to maintain brightness).
Trap: LIH uses a small radiation burstFALSE. Last image hold = ZERO radiation. It holds the last acquired frame.
Trap: Tube below table is safer for staffFALSE. Scatter goes upward toward face/thyroid. Tube above = safer.
Trap: DSA misregistration is caused by contrast injection rateFALSE. Misregistration is caused by patient movement between mask and fill.
Trap: Normal saline is used for RFA hydrodissectionFALSE. D5W only — NS conducts electricity.
Trap: Maximum SID increases patient doseFALSE. Maximum SID reduces dose (inverse square law).
Clinical Scenarios
Scenario 1
Cumulative fluoroscopy time reaches 85 minutes in a complex TIPS. Ka,r reads 5.2 Gy. What is your obligation?
Answer
Notify the referring physician (SRDL threshold is 5 Gy Ka,r per NCRP 168). Schedule follow-up skin assessment at 30 and 60 days.
Scenario 2
During DSA run, the subtracted image shows a ghosting artifact that looks like overlapping vessel outlines. Most likely cause?
Answer
Patient movement between mask acquisition and contrast fill = misregistration artifact. Re-acquire the mask.
Scenario 3
You switch from 9-inch to 6-inch FOV during a procedure. What happens to the patient’s radiation dose?
Answer
Dose increases. Smaller FOV triggers AEC to increase technique (kVp/mA) to maintain image brightness. Counter-intuitive but critical.
Scenario 4
Physician asks for saline to use as hydrodissection fluid during renal RFA. Your response?
Answer
Decline and provide D5W instead. Saline conducts electrical current and creates a path for thermal/electrical injury. D5W is electrically inert.
PACS — Picture Archiving & Communication System
Core Components
Acquisition interface — receives images from fluoro/DSA/CT, assigns to patient
Archive (server) — long-term storage with redundant backup
Workstation confirms patient identity before imaging begins
Images auto-sent to PACS after procedure
Prior imaging retrieved from PACS for intraprocedural roadmapping comparison
Physician reads from PACS; report entered in EMR
Automatic Pressure Injectors
Parameter
Typical Range
Clinical Point
Flow rate
2–25 mL/sec
Must match vessel size; too fast → dissection
Volume
5–50 mL
Enough for arterial phase; minimize contrast load
Pressure limit
150–1200 PSI
5 Fr ≤600 PSI; 4 Fr ≤300 PSI; set per catheter size
Rise time
0.1–0.5 sec
Time to reach target flow; shorter = more abrupt
CRITICAL: Power injectors are NEVER used with microcatheters (2.7–2.9 Fr) — pressure will rupture catheter or dissect vessel. Microcatheter = hand injection only.
Air detector stops injection automatically if air detected in syringe/tubing
Flush syringe/tubing with saline before contrast to remove air
Single patient use only — never reuse syringes or tubing
DSA misregistration = patient movement (not injection rate)
D5W ONLY for RFA hydrodissection (not NS)
Maximum SID = less dose (inverse square law)
42 Questions · 26% of Exam
Vascular Diagnostic
The largest content area. Vascular diagnostic tests access techniques, catheter selection, anatomy, projections, and IVC anatomy for filter placement. Know your projections cold — they’re tested constantly.
Why High-Yield
26% of the exam. Master the projections (LAO 45° for aortic arch, lateral for celiac/SMA, LPO for right renal, RPO for left renal), know the Seldinger technique cold, and understand IVC anatomy variants. Femoral access details and catheter selection are tested heavily.
Vascular Access — Femoral Technique
Femoral Artery Access
Target: common femoral artery over the medial femoral head
Femoral head = backstop for compression post-procedure
Too high (above inguinal lig.) → retroperitoneal hematoma
Too low (below bifurcation) → pseudoaneurysm, AV fistula
Fluoroscopic landmark: inferior border of femoral head
Seldinger: needle → wire → dilator → sheath
Access Complications
Hematoma — most common complication
Pseudoaneurysm — pulsatile mass, visible on US
AV fistula — continuous bruit, venous pulsations
Retroperitoneal bleed — high stick, flank pain, ↓Hgb
IVC Anatomy Variants — Critical for Filter Placement
Variant
Prevalence
Impact on Filter Placement
Duplicated IVC
<1%
Bilateral iliac filters OR suprarenal single filter
Circumaortic left renal vein
3–4%
Must image both limbs; filter above highest LRV
Retroaortic left renal vein
2–3%
Filter below LRV insertion to avoid thrombosis
Left-sided IVC
<0.5%
Crosses midline; access may require repositioning
Cavagram rule: Mandatory before EVERY IVC filter placement regardless of prior imaging. Anatomy can change. Thrombus may extend higher than expected.
Standard filter position: Infrarenal IVC just below the lowest renal vein. Suprarenal placement only when infrarenal is not possible (e.g., thrombus up to renals, pregnancy, duplicated IVC).
Catheter Selection
Catheter
Shape/Use
Key Application
Cobra (C2)
Simple curve
Celiac, SMA, renal arteries from femoral
Simmons (SIM)
Reverse curve
Difficult arch anatomy; subclavian, carotid from femoral
Trap: Celiac/SMA best seen in APFALSE. Lateral projection shows celiac and SMA origin off the anterior aorta.
Trap: Duplicated IVC is common (>5%)FALSE. Prevalence is <1%. Circumaortic LRV is 3–4%.
Trap: Cavagram can be skipped if recent CT shows normal IVCFALSE. Mandatory before every filter placement.
Trap: Right adrenal vein sampling is straightforwardFALSE. It’s technically difficult due to the short right adrenal vein draining directly to the IVC.
Trap: Femoral head is a landmark for arterial compression, not needle entryFALSE. The femoral head is the backstop for BOTH needle entry and post-procedural compression.
Trap: LAO 45° is used for renal arteriesFALSE. LAO 45° = aortic arch. Renal arteries use LPO (right) and RPO (left).
Clinical Scenarios
Scenario 1
Cavagram before IVC filter placement shows two IVC channels from L4 to the confluence. What are your filter options?
Answer
Duplicated IVC (<1% prevalence). Options: bilateral common iliac filters OR single suprarenal filter above the duplication.
Scenario 2
Physician asks for best projection to visualize the celiac axis takeoff during an aortogram. What do you set up?
Answer
Lateral projection. The celiac and SMA originate from the anterior aorta — lateral view shows these origins without vessel overlap.
Scenario 3
Post-femoral arterial puncture, patient has a pulsatile groin mass with a bruit. What complication and what diagnostic test?
Answer
Pseudoaneurysm. Diagnose with duplex ultrasound. Treat with ultrasound-guided compression or thrombin injection.
Scenario 4
During right renal arteriogram, the origin of the right renal artery is not well visualized in AP. What projection do you try?
Answer
LPO (left posterior oblique). This rotates the aorta to open the right renal artery origin.
Central Venous Device Check
Performed for malfunctioning central venous devices: no blood return, poor flow, difficult infusion.
Finding
Fluoroscopic Appearance
Management
Fibrin sheath
Contrast outlines outside of catheter and flows back up tract
Alteplase (tPA) dwell: 2 mg in 2 mL, 30–120 min, then aspirate
Tip malposition
Tip in IJ, axillary, or azygos vein — not in SVC
Reposition over guidewire
Intraluminal thrombus
Filling defect within catheter lumen
tPA dwell; consider exchange if failed
Catheter fracture
Contrast leak at fracture site
Remove catheter; foreign body retrieval if fragment embolized
Pinch-off syndrome
Catheter kinked at costoclavicular space
Remove before complete fracture and embolization
Ideal Catheter Tip Positions
PICC/Port: lower SVC or SVC–RA junction
Too high (above right clavicle): malposition → reposition
Right atrium: arrhythmia risk → pull back
Right ventricle: urgent repositioning — perforation risk
Port Access
Access only with non-coring Huber needle (right-angle bent tip)
Resistance + pain at port site → stop; assess for needle malposition before any injection
Ports sustain 1,000–3,500+ access cycles depending on model
Exam Trap: Lipiodol is oil-based — NOT standard iodinated aqueous contrast. Do not confuse them.
Vascular Anatomy — Aorta & Celiac Territory
Abdominal Aortic Branches (T12–L5)
Branch
Level
Celiac trunk
T12–L1
Superior mesenteric artery (SMA)
L1
Renal arteries (bilateral)
L1–L2
Inferior mesenteric artery (IMA)
L3
Aortic bifurcation → common iliac
L4
Celiac Trunk Trifurcation
Left gastric artery — smallest; supplies lesser curvature of stomach
Splenic artery — largest and most tortuous; runs along superior pancreatic border
Common hepatic artery — gives off GDA then becomes proper hepatic artery → divides into right and left hepatic arteries
Classic trifurcation present in ~89% of individuals
Exam Trap: The gastroduodenal artery (GDA) passes POSTERIOR to the first part of the duodenum. Posterior duodenal ulcers erode the GDA — the classical cause of massive upper GI hemorrhage treated by GDA coil embolization.
Hepatic arterial anatomy is highly variable. Every patient undergoing TACE or hepatic embolization requires complete mapping before treatment.
Variant
Prevalence
Clinical Impact
Replaced RHA from SMA
10–15%
Most common variant — absent right hepatic on celiac arteriogram → catheterize SMA
Replaced LHA from left gastric
~10%
Second most common — runs in lesser omentum → superselect left gastric
Accessory RHA from SMA
~7%
Additional right hepatic supply alongside normal RHA — both must be embolized
Michels Type IX (replaced CHA from SMA)
Rare
Entire liver supplied by SMA — no hepatic branches visible on celiac arteriogram
Normal (Type I)
~55%
Celiac gives off all three vessels; standard hepatic supply
Critical: Before any hepatic embolization — perform celiac arteriogram FIRST, then SMA arteriogram to identify replaced/accessory hepatic vessels. Missing a replaced hepatic artery = incomplete treatment or non-target embolization.
IVC Anatomy & Variants — Critical for Filter Placement
Normal IVC Anatomy
Forms at L4–L5 from junction of common iliac veins
Ascends on the RIGHT side of aorta
Receives renal veins at L1–L2, hepatic veins at T8–T9
Passes through caval hiatus of diaphragm at T8
Standard filter placement: infrarenal (below renal veins)
Left-sided IVC (0.2–0.5%) — joins left renal vein → crosses anterior to aorta; filter in left-sided IVC via left femoral access
Circumaortic LRV (2.4–8.7%) — two left renal veins encircle aorta; retro-aortic limb may be lower — may need suprarenal filter
Retro-aortic LRV (~3%) — single left renal vein crosses posterior to aorta
Cavogram Tip: Duplicated IVC suspected when left common iliac vein inflow defect is absent on right femoral cavogram and infrarenal IVC appears smaller than expected.
Portal Venous System & Mesenteric Collaterals
Portal System Formation
Portal vein = SMV + splenic vein, posterior to pancreatic neck at L1–L2
IMV drains into splenic vein (NOT directly into portal confluence)
Portal vein ascends in hepatoduodenal ligament with hepatic artery (left) and bile duct (right)
Divides at porta hepatis into right and left portal veins
Key Mesenteric Collaterals
Arc of Riolan — middle colic (SMA) → left colic (IMA); central mesentery; prominent in SMA/IMA occlusion
Marginal artery of Drummond — runs along inner colon margin; connects SMA and IMA territories
Pancreaticoduodenal arcade — connects celiac and SMA; preserved if either is occluded
Renal & Adrenal Venous Anatomy
Structure
Left Side
Right Side
Renal vein length
Longer — crosses anterior to aorta
Short — drains directly into IVC
Tributaries
Left gonadal + left adrenal + left phrenic
None — right gonadal and adrenal drain directly into IVC
Adrenal vein
Drains into left renal vein
Drains directly into right IVC posterolateral wall (3–5mm) — most challenging AVS catheterization
Gonadal vein
Left gonadal → left renal vein (varicocele/PCS embolization via left renal vein)
Right gonadal → directly into IVC
Nutcracker Syndrome: Left renal vein compressed between abdominal aorta and SMA → left renal venous hypertension → hematuria, left flank pain, left varicocele/pelvic congestion. Treatment: LRV stenting or transposition.
Cerebrovascular Anatomy — Arch to Circle of Willis
Aortic Arch Branches (Proximal to Distal)
Brachiocephalic (innominate) trunk — divides into right common carotid + right subclavian
Left common carotid artery
Left subclavian artery
Left vertebral artery arises directly from arch in ~6% (between left CCA and left subclavian).
Circle of Willis Connections
AComm (anterior communicating) — bridges L and R anterior circulations (ACAs) — most common aneurysm site (30–35%)
PComm (posterior communicating) — bridges ICA to PCA bilaterally
Vertebral arteries arise from subclavian arteries → unite at pontomedullary junction → basilar artery → bilateral PCAs
Left vertebral dominant ~45%; right dominant ~30%; co-dominant ~25%
CCA Bifurcation (Key for Carotid Stenting)
Bifurcates at C3–C4 (upper thyroid cartilage level)
ICA — larger, posterior/lateral; NO branches in the neck
Standard access site; target puncture over femoral head for hemostasis
Profunda femoris
Arises from CFA 3–5cm below inguinal ligament
Collateral source in SFA occlusion; not a target for angioplasty
Superficial femoral artery (SFA)
Passes through adductor (Hunter's) canal
Most common site of PAD; transitions to popliteal at adductor hiatus
Popliteal artery
Posterior to knee in popliteal fossa
Divides at lower popliteal fossa into AT and tibioperoneal trunk
Anterior tibial artery
Passes through interosseous membrane anteriorly
Continues as dorsalis pedis at foot
Tibioperoneal trunk
Short segment after AT takeoff
Divides into posterior tibial (medial) and peroneal (lateral/fibular)
Posterior tibial artery
Medial calf behind medial malleolus
Supplies plantar foot; palpable posterior to medial malleolus
Peroneal artery
Lateral compartment alongside fibula
Often last patent vessel in critical limb ischemia — may be only outflow
Pelvic Projections: 25° RAO profiles the LEFT internal iliac system; 25° LAO profiles the RIGHT — counterintuitive but high-yield ARRT question.
Quick Recall — Vascular Diagnostic
Aortic arch → LAO 45°
Celiac & SMA → Lateral
Right renal → LPO | Left renal → RPO
Femoral head = backstop for compression AND needle entry landmark
Cavagram mandatory before EVERY IVC filter (no exceptions)
Duplicated IVC <1% → bilateral iliac filters or suprarenal
Circumaortic LRV 3–4% | Retroaortic LRV 2–3%
Right adrenal vein = technically difficult (short, directly to IVC)
42 Questions · 26% of Exam
Vascular Interventional
The most procedure-heavy section. TIPS, IVC filters, embolization, CDT, Y-90, and ablation. Know your PSG targets, embolization agent properties, and CDT contraindications cold.
Why High-Yield
This section rewards techs who understand procedure rationale, not just steps. Know why TIPS targets PSG <12 mmHg, why Gelfoam is temporary, why D5W is used for RFA, and why MWA has no heat-sink effect. These are the distinctions that separate passing from failing.
Tc-99m MAA rule: Always required before Y-90. If lung shunt >20%, do NOT proceed. No exceptions.
Ablation — RFA vs MWA
Feature
RFA (Radiofrequency)
MWA (Microwave)
Mechanism
Ionic agitation → heat
Water molecule oscillation → heat
Heat-sink effect
Yes — vessels >3mm reduce ablation zone
No — not limited by adjacent vessels
Hydrodissection fluid
D5W ONLY (electrically inert)
D5W preferred but less critical
Speed
Slower
Faster (higher temps achieved)
Tumors near vessels
Suboptimal (heat-sink)
Preferred
Exam Traps — Vascular Interventional
Trap: TIPS PSG target is <8 mmHgPARTIAL. <12 mmHg is the standard target per AASLD 2021 for ALL indications. Optimal is <8–10 mmHg but <12 is what’s tested.
Trap: Gelfoam is a permanent embolic agentFALSE. Gelfoam is temporary; recanalizes within days to weeks.
Trap: MWA has a heat-sink effect near vesselsFALSE. MWA is NOT affected by heat-sink. RFA is.
Trap: CDT with tPA is safe 3 months post-strokeFALSE. Stroke <2 months is an absolute contraindication.
Trap: Y-90 Tc-99m MAA scan is optional if CT looks cleanFALSE. Mandatory. Lung shunt fraction >20% = absolute contraindication.
Trap: TIPS encephalopathy rate is <10%FALSE. 25–35% of patients develop hepatic encephalopathy post-TIPS.
Clinical Scenarios
Scenario 1
Post-TIPS, portal pressure is 18 mmHg and hepatic wedge is 9 mmHg. Is the procedure successful?
Answer
PSG = 18 − 9 = 9 mmHg. Yes — this is <12 mmHg. Procedure successful per AASLD criteria.
Scenario 2
Pre-Y-90 Tc-99m MAA scan shows 22% lung shunt fraction. What do you do?
Answer
Do NOT proceed. Lung shunt >20% is an absolute contraindication to Y-90 radioembolization. Radiation pneumonitis risk is too high.
Scenario 3
During RFA of a 3.5cm renal tumor adjacent to the renal vein, ablation zones are consistently smaller than expected. Why?
Answer
Heat-sink effect. The adjacent large vessel (renal vein) dissipates heat, reducing the effective ablation zone. Consider MWA instead.
Scenario 4
Patient had ischemic stroke 6 weeks ago and now has acute iliofemoral DVT with phlegmasia. Can you perform CDT?
Answer
No. Stroke <2 months is an absolute contraindication to CDT. The risk of intracranial hemorrhage is too high.
Atherectomy — Four Types
Type
Device Example
Mechanism
Key Fact
Directional
SilverHawk, TurboHawk
Rotating cutter shaves plaque; collected in nosecone for removal
Debris removed from body in nosecone
Rotational
Rotablator
Diamond burr at high speed; microparticles <7μm pass distally
Debris embolizes distally to lungs
Orbital
Diamondback 360
Eccentric diamond crown; larger zone at higher speed
Bidirectional; one crown size treats multiple vessel diameters
Laser (Excimer)
Turbo-Elite
308 nm UV photons break molecular bonds (no heat)
CTO, in-stent restenosis, thrombus
Exam Trap: Rotational atherectomy debris goes distally (absorbed by lungs). Directional atherectomy debris is collected in the nosecone and removed. This distinction is tested.
No-reflow after rotational atherectomy: treat with intracoronary vasodilators (adenosine, nitroprusside, or verapamil) — NOT stenting.
Endograft Placement — EVAR & TEVAR
EVAR (Abdominal)
Indications: AAA ≥5.5 cm (men), ≥5.0 cm (women), or rapidly enlarging (>0.5 cm/6 mo)
Requires: infrarenal neck ≥10–15 mm, angulation <60°, iliac access ≥7 mm
Post-EVAR follow-up: CTA at 1 month, 12 months, then annually
TEVAR (Thoracic)
Indications: descending TAA ≥5.5–6 cm, traumatic transection (zone 3–4), complicated type B dissection
Spinal cord ischemia = most feared complication — coverage of T8–L2 intercostals
Micropore basket captures debris distal to lesion; retrieved after stent
SpiderFX, Emboshield NAV6, FilterWire EZ
Proximal occlusion
Balloons in ECA + CCA create no-flow field; debris aspirated before restoring flow
Mo.Ma Ultra
Mandatory for carotid artery stenting (CAS) — Class I recommendation. Filter deployed in disease-free distal ICA; retrieved with dedicated catheter after stent + post-dilation. This is a tested ARRT topic.
Foreign Body Retrieval
Common Foreign Bodies
Fractured guidewires (most common)
Broken port catheter fragments (pinch-off syndrome)
Embolized IVC filter struts
Misdeployed coils
Retrieval Devices
Gooseneck snare (Amplatz): most common; 90° loop lassoes object
En Snare: three-loop design for irregular objects
Alligator forceps: jaw-style grasper for right heart objects
Critical technique: Object is snared and pulled INTO a large sheath before extraction — never pulled directly through vessel wall. Sheath must accommodate the object.
Pinch-off syndrome: port catheter compressed between clavicle and 1st rib → fracture → fragment lodges in RV or PA. Recognized by >90° catheter angle at costoclavicular space on fluoroscopy.
Hybrid OR — Interventional Suite vs. Hybrid Operating Room
Feature
IR Suite
Hybrid OR
Imaging
Fixed angiography system
Same + CBCT, fusion imaging capability
Surgical capability
Minor open access only
Full open surgery: anesthesia boom, surgical lighting, instrument tables
Team
IR tech, interventionalist, RN
All of above + surgeon, anesthesiologist, scrub tech
Key advantage
—
In-room surgical conversion without patient transport
Room size
~480–600 sq ft
~750–1,100 sq ft
Why it matters on the exam: EVAR/TEVAR failure → immediate surgical conversion in same room. Fixed flat-panel detectors → superior image quality at lower dose vs. mobile C-arm. Added to ARRT spec in 2022 update.
Procedural Anatomy — Key Relationships for Interventions
Uterine Artery Embolization (UAE)
Uterine artery — first major branch of anterior division of internal iliac
Crosses superior to the ureter (“water under the bridge”)
Ovarian artery arises directly from aorta — separate supply to uterine fundus
Non-target embolization of ovarian artery → premature ovarian failure
Artery of Adamkiewicz — TEVAR Risk
Dominant anterior spinal artery feeder to thoracolumbar cord
Arises from left intercostal/lumbar artery between T8–L1 in ~75%
Left-sided in ~80% of individuals
TEVAR coverage of this level → spinal cord ischemia (paraplegia)
Prevention: CSF drainage + MAP >80–85 mmHg
Hepatic Dome HCC Parasitic Supply
Right inferior phrenic artery (IPA) — most common extrahepatic feeder for HCC in segments VII/VIII (hepatic dome)
Occurs in ~10–15% of HCC cases — must catheterize separately for complete TACE
Other feeders: intercostal arteries, right internal mammary, omental vessels
TIPS Anatomy
Access via right hepatic vein (most common) from right IJV
Needle directed anteriorly, inferiorly, medially toward right portal vein
RFA: heat-sink effect near vessels | MWA: no heat-sink
D5W ONLY for RFA hydrodissection — never NS
28 Questions · 18% of Exam
Nonvascular
Nonvascular covers the breadth of IR: nephrostomy, biliary drainage, biopsy, spine procedures, and drainage. Know your access points, cement properties, and why urosepsis is the most dangerous nonvascular complication.
Why High-Yield
The exam tests nephrostomy access anatomy (posterior lower pole calyx), biliary drainage hierarchy, vertebroplasty vs kyphoplasty distinctions, and complication management. Biopsy needle types and yield are also frequently tested. Urosepsis as the #1 life-threatening nonvascular complication appears on almost every exam.
Percutaneous Nephrostomy — Access Anatomy
Optimal Access
Target: posterior lower pole calyx
Approach: Brödel’s avascular line (lateral avascular plane)
Posterior calyces point posterolaterally → most accessible
Needle passes through renal parenchyma into collecting system
Fluoroscopy + ultrasound guidance for initial access
Upper Pole Risks
Upper pole access → risk of pneumothorax (above 12th rib)
Also: pleural effusion, hydrothorax
Avoid if possible; use subcostal approach
If upper pole required: expiration approach, confirm with CXR post-procedure
Complication
Type
Notes
Urosepsis
Most dangerous
Can be fatal; antibiotics BEFORE procedure mandatory
PTBD (biliary drain) — therapeutic; external or internal-external
External drain — above obstruction only; bile drains to bag
Internal-external — crosses obstruction; bile into duodenum + bag
Fully internalized (stent) — no external drain; bile drains internally only
Key Safety Rules
Antibiotics BEFORE biliary procedure — infected bile = immediate sepsis risk
Right-sided access: right midaxillary line, 8th–9th intercostal space
Left-sided access: subxiphoid/epigastric approach
Cholangiography: contrast fills system; identify level of obstruction
Vertebroplasty vs Kyphoplasty
Feature
Vertebroplasty
Kyphoplasty
Mechanism
PMMA cement injected directly into fracture
Balloon tamp inserted first → cavity created → cement
Height restoration
Minimal to none
Possible (balloon expands before cement)
Cement volume
Higher (no cavity)
Lower (fills cavity)
Cement leak risk
Higher
Lower (cavity contains cement)
Cost
Lower
Higher
Indication
Painful osteoporotic VCF, myeloma
Same; preferred when height restoration desired
Critical safety rule: Cement leak into the epidural space → STOP injection immediately + neurological check. Epidural cement = potential cord compression.
PMMA (polymethylmethacrylate) = bone cement used in both procedures. Viscosity matters: too thin → leaks; too thick → won’t flow.
Biopsy — Needles & Yield
Type
Needle
Sample
Best For
Fine needle aspiration (FNA)
20–25G cutting/aspiration
Cytology (cells)
Thyroid, lymph nodes, cysts
Core needle biopsy
14–18G spring-loaded
Histology (tissue architecture)
Liver, lung, renal, soft tissue
Coaxial technique
Introducer + inner needle
Multiple samples, one pass
Reduces tract seeding risk
Vacuum-assisted
8–11G rotational
Larger samples
Breast, bone marrow
Lung biopsy specific: Most common complication = pneumothorax. Occurs in 20–35% but only ~5% require chest tube. Moderate bleeding risk (INR <1.5 required).
Exam Traps — Nonvascular
Trap: Upper pole nephrostomy is the preferred accessFALSE. Posterior lower pole calyx is standard. Upper pole = pneumothorax risk.
Trap: Kyphoplasty always restores vertebral heightFALSE. Height restoration is possible, not guaranteed. Depends on fracture acuity.
Trap: Vertebroplasty has lower cement leak risk than kyphoplastyFALSE. Vertebroplasty injects directly — higher leak risk. Kyphoplasty fills a pre-formed cavity.
Trap: Perinephric hematoma is the most dangerous nephrostomy complicationFALSE. Most common yes, but most dangerous = urosepsis (can be fatal).
Trap: Biliary procedures don’t require pre-procedure antibiotics if patient is afebrileFALSE. All biliary procedures require antibiotics BEFORE starting, regardless of fever status.
During PTBD, patient becomes febrile and hypotensive immediately after bile is aspirated. What is happening and what do you do?
Answer
Urosepsis/biliary sepsis from infected bile entry into bloodstream. Broad-spectrum antibiotics immediately, IV fluids, blood cultures, and expedite drainage. This is life-threatening.
Scenario 2
During kyphoplasty cement injection, the patient reports sudden new back pain. Fluoroscopy shows cement tracking toward the posterior cortex. What do you do?
Answer
Stop injection immediately. Assess for epidural leak. Neurological check. Epidural cement can cause cord compression — this is a surgical emergency if neurological deficits develop.
Scenario 3
Nephrolithiasis patient needs nephrostomy drainage above the 11th rib due to anatomy. Post-procedure, patient is dyspneic. First test?
Answer
Chest X-ray to rule out pneumothorax. Upper pole/intercostal access carries risk of pneumothorax. May require chest tube if large.
Scenario 4
Pathology requests tissue architecture for suspected hepatocellular carcinoma. Which biopsy needle type do you use?
Answer
Core needle biopsy (14–18G spring-loaded). FNA provides cytology only — insufficient for tissue architecture/histology required for HCC diagnosis.
Suprapubic Catheter Placement
Indications: urinary retention not amenable to urethral catheterization (stricture, trauma, false passage); long-term bladder drainage
Critical requirement: bladder must be adequately distended (>300 mL) — confirmed by ultrasound before puncture
Normal opening pressure: 7–18 cmH&sub2;O (lateral decubitus)
Post-LP headache (10–30%): supine, fluids, caffeine; blood patch if severe
Myelogram — Critical Safety
Contrast: Iohexol (Omnipaque) ONLY — nonionic water-soluble, intrathecally approved
NEVER: ionic contrast (seizures), gadolinium (not standard of care), barium (absolute CI)
Post-procedure: keep patient upright 30–45° for 4–6 hours
Post-myelogram CT within 60 minutes
Epidural Steroid Injection (ESI)
Approach
Best For
Notes
Transforaminal (TFESI)
Unilateral radiculopathy; targeted
Most common in IR; “Scotty dog” oblique view; inject to safe triangle
Interlaminar (ILESI)
Central/bilateral symptoms
Broad spread; between laminae
Caudal
L5–S1 predominant; prior surgery
Via sacral hiatus
CRITICAL SAFETY RULE: For cervical transforaminal ESI — use dexamethasone ONLY (non-particulate). Triamcinolone or methylprednisolone (particulate steroids) can embolize to the vertebral or anterior spinal artery → cord infarction / stroke. This is a high-stakes ARRT exam topic.
Paracentesis — SIR Risk & Albumin Replacement
SIR Bleeding Risk Classification
Paracentesis = LOW risk — same as thoracentesis
No specific INR or platelet correction threshold required
Coagulation parameters do not reliably predict bleeding for low-risk procedures
IV albumin: 6–8 g per liter removed, given after procedure
Normal saline is NOT an acceptable substitute
Volumes <5 L: albumin not required
Exam Trap: Candidates assume coagulopathy requires correction before paracentesis — SIR guidance does NOT support routine correction for this LOW-risk procedure.
Procedural Anatomy — Nonvascular Access
Nephrostomy Access Anatomy
Target: posterior lower pole calyx via posterolateral approach
Access through posterior axillary line — avoids descending colon anteriorly
Needle directed in axis of infundibulum toward calyx
Upper pole access reserved for ureteropelvic junction obstruction or complex stone work
Collecting system accessed under fluoroscopic + ultrasound guidance
Biliary Anatomy
Right + Left hepatic ducts → common hepatic duct at porta hepatis
Cystic duct joins CHD → forms common bile duct (CBD)