Clinical question: Hemorrhage? Herniation? Ischemia? — Ordered for trauma, sudden severe headache ("worst headache of life"), acute neuro change, or altered mental status.
01Hemorrhage — Look First
Subdural hematoma (crescentic)
Epidural hematoma (biconvex)
Subarachnoid hemorrhage — sulci, cisterns
Intraparenchymal hemorrhage
Intraventricular hemorrhage
Basal cistern hyperdensity
Hyperdense vessel sign (LVO clue)
02Midline & Mass Effect
Septum pellucidum position
Third ventricle centered
Basal cistern effacement
Sulcal effacement
Uncal / tonsillar herniation
Must measure: midline shift in mm
03Ischemia
Insular ribbon loss
Lentiform nucleus obscuration
Cortical sulcal effacement
Focal hypoattenuation
Dense MCA sign → ASPECTS
04Ventricles
Hydrocephalus (all 4 ventricles)
Trapped ventricle
Basal cistern patency
05Bone Window
Skull fractures
Temporal bone
Orbital walls
Mastoid air cells
Paranasal sinuses
—ASPECTS Regions (subtract 1 each)
CCaudate
LLentiform nucleus
ICInternal capsule
IInsula
M1Ant MCA cortex
M2MCA at insular level
M3Post MCA cortex
M4Above M1
M5Above M2
M6Above M3
Start at 10. Score ≥6 = eligible for thrombectomy (generally)
🚨 Must Report
Hemorrhage — type + location
Midline shift — mm, direction
Herniation — type
Early ischemia / ASPECTS score
Hydrocephalus
Skull fracture
⚠ Don't Miss
Subtle SAH — scroll every cistern
Insular ribbon loss — early ischemia
Bone windows in trauma
Posterior fossa — easy to miss
📋 Say This — Dictation Language
ICH: "There is a [X] mL hyperdense intraparenchymal hematoma in the [location] measuring [X×X×X] cm with [X] mm of surrounding edema and [X] mm of midline shift to the [right/left]. The basal cisterns are [patent/effaced]."
SDH: "There is a [right/left][acute/subacute/chronic] subdural hematoma measuring up to [X] mm in thickness with [X] mm of midline shift. [No herniation is identified / Uncal herniation is present]."
SAH: "There is hyperattenuation within the [basal cisterns / bilateral Sylvian fissures / sulci] consistent with subarachnoid hemorrhage. [Aneurysmal origin cannot be excluded — recommend CTA]."
≠ Don't Call It Pathology
Arachnoid granulations in venous sinuses — smooth, CSF density
Developmental venous anomaly (DVA) — "caput medusae," enhances, normal
Mega cisterna magna — posterior fossa CSF, communicates, normal
Pineal cyst <1 cm, thin wall, no enhancement — normal
Falcine calcifications — normal, especially older patients
Radiology Roadmap — On-Call Survival Guide
CTA Head
On-Call Search Pattern
Clinical question: Is there a large vessel occlusion (LVO) or aneurysm? — Ordered when NCCT shows dense MCA sign, early ischemia, or for rule-out aneurysmal SAH. ALWAYS read NCCT first.
Fetal PCA — PCA from ICA, not basilar (20–30% of people)
Hypoplastic A1 — one ACA smaller than other, normal
Absent PCom — common, not pathology
Hypoplastic vertebral — usually left smaller, normal
📋 Say This — Dictation Language
LVO found: "CTA demonstrates abrupt cutoff of the [right/left] [M1/basilar/ICA terminus] consistent with large vessel occlusion. The contralateral vasculature is patent. ASPECTS score is [X]/10 on NCCT."
No LVO: "CTA of the head demonstrates patent intracranial vasculature without evidence of large vessel occlusion. No aneurysm is identified. The parenchyma demonstrates [no acute change / early ischemic changes in the _____ territory]."
Aneurysm: "There is a [X] mm saccular aneurysm at the [ACom / ICA–PCom / MCA bifurcation / basilar tip]. [No / There is] evidence of subarachnoid hemorrhage."
Radiology Roadmap — On-Call Survival Guide
CTA Neck
Search Pattern + NASCET
Clinical question: Carotid stenosis? Dissection? — Ordered for stroke workup, TIA, neck trauma, or carotid bruit. Always look at the arch and both sides fully before calling.
⚠ Never measure inside the bulb — always use distal ICA as reference
🚨 Must Report
% stenosis (NASCET) — R vs L
Dissection — YES/NO — side
Occlusion — YES/NO
Dominant vertebral side
⚠ Don't Miss
Measuring inside the bulb = underestimates stenosis
Missing dissection — look for tapering / intimal flap
Missing arch pathology
📋 Say This — Dictation Language
Stenosis: "There is [mild/moderate/severe] stenosis of the [right/left] internal carotid artery at the bifurcation, with NASCET stenosis of approximately [X]%. [Calcified/mixed] plaque is present. [No ulceration is identified / Plaque ulceration is suspected]."
Dissection: "There is a [right/left] internal carotid artery dissection with tapered luminal narrowing from the [level], consistent with intramural hematoma. The distal ICA is [patent / occluded]."
Radiology Roadmap — On-Call Survival Guide
CT C-Spine
Search Pattern
Clinical question: Fracture? Instability? — Ordered for trauma with neck pain, midline tenderness, high-energy mechanism, or altered mental status. Sagittal reformats first, always.
01Sagittal — 4 Lines (Start Here)
Anterior vertebral line
Posterior vertebral line
Spinolaminar line
Spinous process tips
Step-off at any line = fracture / subluxation until proven otherwise
02Craniocervical (High Yield)
Occipital condyles
C1 ring integrity (Jefferson)
ADI >3 mm adult → instability
Prevertebral soft tissue
03Coronal — Lateral Masses
Lateral mass symmetry
Facet alignment
04Axial — Bone
Vertebral body cortex
Pedicles
Facets (dislocation?)
Lamina
Retropulsion
05Soft Tissue Window
Spinal canal compromise
Epidural hematoma
Cord signal (limited on CT)
06Don't Miss
Lung apices
Subcutaneous emphysema
Soft tissue swelling
🚨 Must Report
Fracture — type + level
Alignment — any step-off
Canal compromise — % and level
C1/C2 instability
⚠ Don't Miss
C1 burst fracture (Jefferson) — look on coronal + axial
Facet dislocation — step-off at posterior vertebral line
Fracture: "There is a [type] fracture of the [C_ vertebral body / posterior elements] with [no/X mm] retropulsion and [no/estimated X%] canal compromise. Alignment is [maintained / disrupted with X mm subluxation] at [C_–C_]."
Normal: "The cervical vertebral body heights, alignment, and posterior elements are maintained. No acute fracture or malalignment is identified. Prevertebral soft tissues are unremarkable."
Radiology Roadmap — On-Call Survival Guide
MRI Brain — DWI · ADC · FLAIR · T1 Gad · GRE/SWI
On-Call Search Pattern
Clinical question: Acute stroke? Mass? Infection? — Ordered when CT is negative but neuro symptoms persist, or to characterize a CT abnormality. DWI is your first sequence — always.
01DWI First — Rule Out Stroke
Cortical ribbon restriction
Deep gray / subcortical restriction
Brainstem — easy to miss
Check ADC: dark = true restriction (not shine-through)
Met: uniform ring, gray-white junction, often multiple
Tumefactive MS: open ring, adjacent WM lesions
🚨 Must Report
Acute infarct — territory + DWI/FLAIR status
Mass + midline shift mm
Ring-enhancing lesion — location + size
Leptomeningeal enhancement
Venous sinus thrombosis
⚠ Don't Miss
T2 shine-through — ALWAYS check ADC
Brainstem DWI restriction — check every case
Early leptomeningeal enhancement — subtle
📋 Say This — Dictation Language
Acute infarct: "DWI demonstrates restricted diffusion in the [right/left MCA territory / posterior circulation / brainstem] with corresponding ADC hypointensity, consistent with acute infarction. FLAIR is [dark — onset likely <4.5 hours / bright — onset likely >4.5 hours]. No hemorrhagic transformation on GRE."
Ring-enhancing lesion: "There is a [X] cm ring-enhancing lesion in the [location] with surrounding vasogenic edema and [X] mm of midline shift. The center demonstrates [restricted diffusion, suggesting abscess / no restricted diffusion]. [Single lesion / Multiple lesions are present]."
≠ Don't Call It Pathology
DVA — caput medusae, no treatment needed, enhances
Dilated perivascular spaces — follow CSF signal on all sequences
Choroid plexus cysts — common, no follow-up needed
Radiology Roadmap — On-Call Survival Guide
CT PE (CTPA)
Search Pattern + Severity Stratification
Clinical question: Is there a PE? If yes — how bad? — Ordered for chest pain, dyspnea, hypoxia, tachycardia, or elevated D-dimer. Check study quality before calling it negative.
00Study Quality First
PA opacification adequate?
Motion artifact (lower lobes)?
Bolus timing — PA must be bright
Streak artifact limiting eval?
If limited → say so. Never call negative on a poor-quality study.
01Pulmonary Arteries (Central → Peripheral)
Main PA — saddle PE?
Right PA, left PA
Lobar arteries
Segmental arteries
Subsegmental — only if confident
Clot: central filling defect, eccentric, abrupt cutoff, enlargement
02Right Heart Strain (Critical)
RV:LV ratio ≥ 1 → right heart strain
Septal bowing toward LV
Contrast reflux IVC / hepatic veins
Main PA enlargement
03Lungs & Pleura
Peripheral wedge opacity (infarct)
Pleural effusion
Consolidation / ground-glass
04Alternative Diagnoses
Aortic dissection — look at aorta
Pneumonia
Pericardial effusion / tamponade
Mass
🚨 Must Report
PE present or absent
Most proximal clot location
Right heart strain — YES / NO
If limited — state why
⚠ Don't Miss
Flow artifact lower lobe PAs — windowing trick
Saddle embolus — look at main PA first
Right heart strain — changes management
📋 Say This — Dictation Language
PE positive: "Filling defects are present within the [right/left/bilateral] [main/lobar/segmental] pulmonary arteries consistent with acute pulmonary emboli. The most proximal clot is at the [level]. RV:LV ratio is [X], [consistent with right heart strain / without right heart strain]. [No / There is] interventricular septal bowing."
PE negative: "No filling defects are identified within the main, lobar, or segmental pulmonary arteries to suggest pulmonary embolism. The right-to-left ventricular ratio is normal. [Incidental finding: ___]."
PE Severity Stratification
Massive
Hemodynamic instability SBP <90 or shock → Call now
Submassive
Hemostable + RV:LV ≥1 or ↑ troponin → Urgent
Low-Risk
Hemostable + No RH strain + Normal troponin
Radiology Roadmap — On-Call Survival Guide
Chest X-Ray
ABCDE Search Pattern
The highest-volume overnight study. Use ABCDE every time — the systematic approach prevents the classic "saw the pneumonia, missed the malpositioned ET tube" error.
AAirway
Trachea midline
Deviation — mass, tension, atelectasis
Carina angle <70°
BBreathing
Symmetry
Consolidation
Interstitial markings
Ground-glass / hazy opacities
Lobar collapse — LUL veil, RML silhouette, etc.
CCardiac
CTR >50% on PA → enlarged
Contour abnormality
DDiaphragm
CP angles — effusion
Free air under diaphragm
Hemidiaphragm elevation
EEverything Else
Bones — ribs, clavicles
Soft tissues
Lines / tubes / devices
—Lines & Tubes — Positions
ET tube: tip 3–5 cm above carina (T4–T6 level)
NG tube: below diaphragm, tip in stomach
Central line: SVC at cavoatrial junction
Chest tube: apex (PTX) or base (effusion)
🚨 Must Report
Pneumothorax — size + tension signs
Consolidation / pneumonia
Pulmonary edema
Pleural effusion
Malpositioned lines / tubes
Free air under diaphragm
⚠ Classic Misses
Apical PTX — always check lung windows
Retrocardiac opacity — LLL collapse
NG tube in lung — always verify below diaphragm
ET tube too low — right main bronchus intubation
Free air under diaphragm — get lung windows
📋 Say This — Dictation Language
PTX: "There is a [right/left][small/moderate/large] pneumothorax. [No / There is] mediastinal shift. The visualized lung is [not / partially] collapsed. [Tension pneumothorax cannot be excluded on this supine study]."
ET tube: "The endotracheal tube tip is [X] cm above the carina, [within normal limits / high — recommend advancement / low — recommend withdrawal X cm]."
Pulmonary edema: "There is bilateral perihilar haziness, vascular redistribution, and Kerley B lines consistent with pulmonary edema. [Cardiomegaly is / is not] present. Small bilateral pleural effusions."
Radiology Roadmap — On-Call Survival Guide
CT Abdomen / Pelvis
On-Call Search Pattern
Clinical question: Free air? Obstruction? Appendicitis? Bleeding? — Ordered for acute abdominal pain, fever, elevated WBC, or hemodynamic instability. Look for the life-threatening findings first.
01Life-Threatening — Look First
Free intraperitoneal air — anterior, on lung windows
SBO: "There is small bowel obstruction with dilated loops measuring up to [X] cm. A transition point is identified at the [location]. [No pneumatosis is identified / Pneumatosis is present suggesting ischemia — urgent surgical consultation recommended]. No free air."
Appendicitis: "The appendix is visualized measuring [X] mm in diameter with periappendiceal fat stranding. [No / A fecolith is present. No / Extraluminal air is present suggesting perforation]."
Free air: "There is free intraperitoneal air, most prominent in the [anterior perihepatic / subphrenic] region, consistent with viscus perforation. Urgent surgical consultation is recommended."
Radiology Roadmap — On-Call Survival Guide
Ultrasound — FAST · GB · Renal · DVT · OB/GYN
On-Call Search Pattern
The most operator-dependent modality. Your thoroughness directly determines the result. In trauma, FAST is the first imaging — positive FAST in an unstable patient = OR, not CT.
01FAST — 4 Windows
RUQ: Morrison's pouch, right paracolic gutter, subphrenic
LUQ: Splenorenal recess, left paracolic gutter
Pelvis: Pouch of Douglas / rectovesical space
Subxiphoid: Pericardial effusion + cardiac motion
Any anechoic free fluid = positive FAST. Even a sliver matters.
02eFAST — Pneumothorax
Lung sliding present = no PTX at that point
M-mode: Seashore sign = normal
M-mode: Stratosphere sign = PTX
B-lines ≥3/zone = interstitial edema
03Cholecystitis
Gallstones (shadowing, mobile)
GB wall >3 mm
Pericholecystic fluid
Sonographic Murphy's sign
GB distension >5 cm transverse
CBD <6 mm (post-chole <8 mm)
04DVT — Compression
Common femoral vein (groin)
Femoral vein (thigh)
Popliteal vein (knee)
Full compression = no DVT
Incompressible = DVT
05OB / GYN
IUP: yolk sac in gestational sac = confirmed IUP
Discriminatory zone: βhCG >1500 → should see IUP on TVUS
Acute cholecystitis: "Multiple gallstones are present with a positive sonographic Murphy's sign. The gallbladder wall measures [X] mm in thickness with pericholecystic fluid. These findings are consistent with acute cholecystitis."
DVT: "The [right/left][common femoral / femoral / popliteal] vein is incompressible with no internal color flow, consistent with acute deep venous thrombosis. The [contralateral side / remaining veins] are compressible."
Torsion: "The [right/left] ovary is enlarged measuring [X×X×X] cm with absent Doppler flow. A [whirlpool sign / follicular rim] is identified. These findings are highly suspicious for ovarian torsion. Urgent surgical consultation recommended."
Radiology Roadmap — On-Call Survival Guide
Trauma CT — Pan-Scan
Search Pattern + AAST Grading
Speed and completeness matter equally. Look for the killing finding first (active bleed, tension PTX, aortic injury), then grade every organ systematically. Active extravasation = call immediately.
Arterial phase blush — same density as aorta (~300 HU)
Venous phase: expands or persists
Pseudoaneurysm: round, contained
Always check arterial phase — never miss a blush
🚨 Must Report
Active extravasation — location + phase
Solid organ grade (spleen, liver, kidney)
PTX — size + tension
Aortic injury
Bowel injury signs
Pelvic fracture — stable or unstable
⚠ Don't Miss
Arterial blush on venous-only review
Diaphragm rupture — herniated bowel loops
Bowel injury — mesenteric stranding + free fluid, no solid organ source
Undergrading spleen — delayed rupture risk
📋 Say This — Dictation Language
Splenic laceration: "There is a AAST Grade [II/III/IV] splenic laceration measuring [X] cm in depth with a [subcapsular / perisplenic] hematoma. [No / There is] active contrast extravasation. Perisplenic free fluid is present."
Active bleed: "There is active arterial contrast extravasation in the [location] measuring approximately [X] cm, with expanding hyperdensity on venous phase. Urgent surgical / IR consultation is recommended."
Radiology Roadmap — On-Call Survival Guide
Quick Reference
Must-Report Measurements
🧠 CT Brain
Midline shift — reportmm + direction
Cistern effacementpresent / absent
Herniation typeuncal / subfalcine / tonsillar
ASPECTS score0–10 (≥6 = eligible)
ICH volume (ABC/2)mL
🫁 CT PE
RV:LV ratio ≥ 1→ Right heart strain
Septal bowing toward LVreport
Contrast reflux IVC/hepaticreport
Most proximal clot locationmain / lobar / segmental
🧬 CTA Neck
NASCET formula(1 − B/A) × 100
Mild stenosis<50%
Moderate stenosis50–69%
Severe stenosis≥70%
🦴 C-Spine
Spinal canal — narrow<13 mm
Canal severe stenosis<10 mm
ADI adult instability>3 mm
🩻 CXR Lines
ET tube above carina3–5 cm
NG tube — verifybelow diaphragm, in stomach
Central line tipSVC / cavoatrial junction
Cardiothoracic ratio (PA)>50% = enlarged
🔊 Ultrasound
GB wall thickening>3 mm
CBD normal<6 mm (post-chole <8 mm)
GB distension>5 cm transverse
IUP discriminatory zoneβhCG >1500–2000
Always Include in Report
Most proximal clot location for PE
Side (R vs L) for carotid stenosis and DVT
Exact vessel + segment for LVO (e.g., right M1, basilar)
If study limited → state why
Midline shift in mm, not just "present"
Radiology Roadmap — On-Call Survival Guide
Escalation Protocol
When to Call the Attending — No Exceptions
🚨 Call Immediately — Neuro
LVO on CTA — stroke team needs to be activated
Basilar artery occlusion
Herniation / uncal herniation
Epidural hematoma — surgical emergency
Rapidly expanding subdural
Aneurysmal SAH pattern
DWI bright + FLAIR dark — unknown onset
🚨 Call Immediately — Vascular / Abdomen
Aortic dissection Type A — cardiac surgery now
Ruptured AAA — active extravasation
Active arterial hemorrhage — any location
SMA occlusion / mesenteric ischemia
Tension pneumothorax
Pericardial tamponade
Saddle PE with right heart strain
Ovarian / testicular torsion — absent flow
Ectopic pregnancy with hemoperitoneum
Pneumoperitoneum (perforation)
⚠ Urgent — Call Within Minutes
New ICH in anticoagulated patient
Cord compression + neurologic symptoms
High-grade SBO — closed loop
Pneumatosis + portal venous gas
DVT extending to IVC
Unexpected malignancy on study not ordered for it
Epiglottitis — airway
⚠ Communicate Before Morning
Aortic dissection Type B (uncomplicated)
New or growing aneurysm
Pulmonary nodule needing urgent follow-up
Unexpected adrenal mass (>4 cm)
Significant incidental finding
📞 Phone Script — SBAR Format (Use Every Time)
S — Situation: "Hi Dr. [Attending], this is [your name], the radiology resident on call. I'm calling about an urgent finding." B — Background: "[Patient name / MRN], [age, sex], had a [study type] at [time], ordered for [reason]." A — Assessment: "I'm seeing [exact finding + location + severity]." R — Recommendation: "I think this needs [immediate attention / surgical consult / correlation with clinical exam]."
Then document: "Called Dr. [name] at [HH:MM]. Communicated [finding]. They acknowledged and plan to [action]."