ARRT RADIOGRAPHY CLUES GUIDE
Ultimate Clues, Positioning Shortcuts, & Mnemonic Cram Sheet
1. The Master "If You See This, Think This" Registry Matrix
Use this master table for immediate pattern recognition during the exam. Experienced tutors
advise reading the question stem, looking for these exact key triggers, and predicting the correct
answer before even looking at the multiple-choice distractors.
If You See This Word/Phrase in Think of This Core This is the "Registry Correct"
the Question Concept / Mnemonic Answer Hook
Greatest source of technologist The Patient Patient (not the tube, barrier, or room
scatter / dose wall)
Contrast media + Metformin / Withhold Metformin 48 Hold at exam and 48 hours post-
Glucophage hrs procedure; monitor kidneys
Unlawful touching without consent Battery = Body Battery (Assault is only the threat of
touching)
Employer or hospital is legally Boss Pays Respondeat Superior
responsible
Contaminated inanimate object Fomite = Object Fomite (wheelchairs, cassettes,
markers, pens)
Patient has a Do Not Resuscitate DNR does NOT mean No Provide full diagnostic imaging, comfort,
order Care and care; only CPR is withheld
Uncontrolled background radiation Air Kerma / Exposure Gy_a (Air Kerma) or Coulomb/kg
in air (Exposure)
Volts and Resistance given; asking Ohm's Law: V = I * R Current (I) = V / R (express in Amperes
for current / ohms)
Double or half of distance from Inverse Square Law Double distance = 1/4 dose; Half
radiation distance = 4x dose
Change distance, maintain Exposure Maintenance Direct square relationship: double SID =
receptor exposure Law 4x the mAs
, Add a grid or change grid ratio Grid Conversion GCF Divide starting mAs by old GCF, then
multiply by new GCF
Fuji exposure indicator of 100 vs. Fuji S-Number is Inverse 100 is overexposed; 400 is
400 underexposed
Kodak / Carestream EI of 1700 vs. Kodak EI is Direct 1700 is underexposed; 2300 is
2300 overexposed
Grainy, blotchy, mottled digital Quantum Mottle = Noise Insufficient mAs (mottle is cured ONLY
image by increasing photon count)
Extreme overexposure with Detector Saturation Gross overexposure (requires
uncorrectable black areas immediate repeat; cannot be rescaled)
Amorphous Selenium (a-Se) SelenDIRECT Direct conversion (x-rays to charge with
Digital Receptor zero lateral light blur)
Amorphous Silicon (a-Si) Digital SILIcon (Silly Extra Step) Indirect conversion (uses Cesium Iodide
Receptor scintillator to make light first)
A patient with high, transverse Short & Stout = Up & Out Hypersthenic body habitus
stomach
A patient with low, vertical, J- Tall & Thin = Down & In Asthenic / Hyposthenic body habitus
shaped stomach
Posterior oblique cervical spine Posterior = UP & FAR Demonstrates intervertebral foramina
(RPO/LPO) farther from IR (with cephalad angle)
Anterior oblique cervical spine Anterior = DOWN & Demonstrates intervertebral foramina
(RAO/LAO) CLOSE closest to IR (with caudad angle)
Oblique lumbar spine Scotty Dog Scotty Dog Parts Neck = Pars Interarticularis; Eye =
parts Pedicle; Ear = Superior Facet
Lucency/fracture across Scotty Spondylolysis Collar on the Scotty Dog represents
Dog neck Spondylolysis
Posterior oblique lumbar spine Lumbar DOWN Demonstrates downside zygapophyseal
(RPO/LPO) joints closest to IR
Posterior oblique SI joints SI Joints = Side UP Demonstrates SI joint farthest from IR
(RPO/LPO) (RPO shows Left SI joint)
Ultimate Clues, Positioning Shortcuts, & Mnemonic Cram Sheet
1. The Master "If You See This, Think This" Registry Matrix
Use this master table for immediate pattern recognition during the exam. Experienced tutors
advise reading the question stem, looking for these exact key triggers, and predicting the correct
answer before even looking at the multiple-choice distractors.
If You See This Word/Phrase in Think of This Core This is the "Registry Correct"
the Question Concept / Mnemonic Answer Hook
Greatest source of technologist The Patient Patient (not the tube, barrier, or room
scatter / dose wall)
Contrast media + Metformin / Withhold Metformin 48 Hold at exam and 48 hours post-
Glucophage hrs procedure; monitor kidneys
Unlawful touching without consent Battery = Body Battery (Assault is only the threat of
touching)
Employer or hospital is legally Boss Pays Respondeat Superior
responsible
Contaminated inanimate object Fomite = Object Fomite (wheelchairs, cassettes,
markers, pens)
Patient has a Do Not Resuscitate DNR does NOT mean No Provide full diagnostic imaging, comfort,
order Care and care; only CPR is withheld
Uncontrolled background radiation Air Kerma / Exposure Gy_a (Air Kerma) or Coulomb/kg
in air (Exposure)
Volts and Resistance given; asking Ohm's Law: V = I * R Current (I) = V / R (express in Amperes
for current / ohms)
Double or half of distance from Inverse Square Law Double distance = 1/4 dose; Half
radiation distance = 4x dose
Change distance, maintain Exposure Maintenance Direct square relationship: double SID =
receptor exposure Law 4x the mAs
, Add a grid or change grid ratio Grid Conversion GCF Divide starting mAs by old GCF, then
multiply by new GCF
Fuji exposure indicator of 100 vs. Fuji S-Number is Inverse 100 is overexposed; 400 is
400 underexposed
Kodak / Carestream EI of 1700 vs. Kodak EI is Direct 1700 is underexposed; 2300 is
2300 overexposed
Grainy, blotchy, mottled digital Quantum Mottle = Noise Insufficient mAs (mottle is cured ONLY
image by increasing photon count)
Extreme overexposure with Detector Saturation Gross overexposure (requires
uncorrectable black areas immediate repeat; cannot be rescaled)
Amorphous Selenium (a-Se) SelenDIRECT Direct conversion (x-rays to charge with
Digital Receptor zero lateral light blur)
Amorphous Silicon (a-Si) Digital SILIcon (Silly Extra Step) Indirect conversion (uses Cesium Iodide
Receptor scintillator to make light first)
A patient with high, transverse Short & Stout = Up & Out Hypersthenic body habitus
stomach
A patient with low, vertical, J- Tall & Thin = Down & In Asthenic / Hyposthenic body habitus
shaped stomach
Posterior oblique cervical spine Posterior = UP & FAR Demonstrates intervertebral foramina
(RPO/LPO) farther from IR (with cephalad angle)
Anterior oblique cervical spine Anterior = DOWN & Demonstrates intervertebral foramina
(RAO/LAO) CLOSE closest to IR (with caudad angle)
Oblique lumbar spine Scotty Dog Scotty Dog Parts Neck = Pars Interarticularis; Eye =
parts Pedicle; Ear = Superior Facet
Lucency/fracture across Scotty Spondylolysis Collar on the Scotty Dog represents
Dog neck Spondylolysis
Posterior oblique lumbar spine Lumbar DOWN Demonstrates downside zygapophyseal
(RPO/LPO) joints closest to IR
Posterior oblique SI joints SI Joints = Side UP Demonstrates SI joint farthest from IR
(RPO/LPO) (RPO shows Left SI joint)
