Introduction to
Radiology
Michael Solle, MD, PhD
Introduction to Radiology
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I: Radiology Basics and High Yield Topics
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Modalities in Radiology and Cases
Contrast
How to look at studies
Catheters: tunneled vs non-tunneled
Drains and Tubes
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II: How to Consult Radiology
III: Plain Film Imaging of the Abdomen
IV: Parting Thoughts
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Dr. Molina and Chest Radiology
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Definition of Radiology
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Radiology is a medical
specialty using
medical imaging
technologies to
diagnose and treat
patients.
I: Basics/Hi-Yield:
Radiology Modalities
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Conventional radiographs (“x-rays”)
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Fluoroscopy
Mammography
Computed Tomography (CT)
Nuclear Medicine (NM)
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PET-CT combines CT and NM
Ultrasound (US)
Magnetic resonance imaging (MRI)
Radiology Modalities
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Conventional
Radiography
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Lingo:
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Density
Opacity
Observable Densities:
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Metal
Bone
Soft Tissue
Gas
Radiology Modalities
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Fluoroscopy
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“Live” imaging
Contrast agents often
given
Radiology Modalities
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Computed Tomography
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Lingo:
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Hounsfield Units
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Attenuation
Density
Enhancement
-1000 air ***
-100 fat
0 water ***
20-80 soft tissues
100’s bone/Ca/contrast
>1000’s metal
Large radiation dose
Radiology Modalities
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Nuclear Medicine
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Lingo:
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Physiologic imaging
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Radionuclides
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Technetium
Radiopharmaceuticals
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Counts or Activity
“Choletec”
Radioactivity stays with
the patient until cleared or
decayed
Radiology Modalities
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Ultrasound
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Lingo
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Echogenicity
Shadowing
Doppler for flow
No radiation
Can be portable
Relatively inexpensive
Radiology Modalities
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MRI
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Lingo:
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No radiation
Strong magnetic field
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Signal intensity
T1
T2
Enhancement
No pacemakers
No electronic implants
Small, loud tube and patients
must be able to hold still
Relatively expensive
Radiology Modalities:
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Four different cases of Abdominal Pain
Can you develop a differential diagnosis
based location of the abdominal pain?
Can you identify the modality used?
Diagnosis?
Case 1: RUQ pain
Case 2: RUQ pain: Diagnosis?
Case 3: RLQ pain: Diagnosis?
Case 4: RLQ pain: Diagnosis?
I: Radiology Modalities Summary:
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Conventional radiographs (“x-rays”):
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Computed Tomography (CT):
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Physiological imaging, great for specific questions.
Ultrasound (US)
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Diagnostic dilemmas (pricier, variable speed b/c of contrast).
High radiation.
Nuclear Medicine
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Great place to start (cheap, fast, low radiation).
Relatively inexpensive, and no radiation.
Highly dependent on patient’s body size and US operator.
Magnetic resonance imaging (MRI)
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Relatively expensive, no radiation, not fast.
Unmatched ability to contrast healthy tissue from disease.
I: Basics/Hi-Yield:
A few words on contrast
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CT contrast:
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IV- contains Iodine; which attenuates x-rays
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Contraindicated in renal failure (acute and chronic) b/c of risk of
contrast induced nephropathy
Allergy issues
Power injected and causes vaso-vagal reactions (NPO)
PO- contains dilute iodine or sometimes very dilute barium
(flouro studies typically use barium)
MRI contrast:
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IV- contains gadolinium chelated to a carrier molecule; acts as a
paramagnetic molecule which increases signal on T1 images
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Contraindicated in renal failure (acute and particularly ESRD) b/c of
risk of NSF
I: Basics/Hi-Yield:
A few words on contrast
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AVOIDING CONTRAST IN THE SETTING OF
ACUTE RENAL FAILURE IS DIFFICULT for the
radiologist, because the creatinine may be
normal.
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In hyper-acute renal failure, the creatinine hasn’t
risen yet. Decreased urine output or anuria is
acute renal failure – regardless of the creatinine.
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Remember; first do no harm! Non-contrast
studies can often be quite helpful.
I: Basics/Hi-Yield:
Looking at Imaging Studies:
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Adequate Study?
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Correctly labeled with patient’s name, MR#, and the date
of the study?
Technically adequate?
Systematic versus Focused look at a study:
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Radiologist does both!
As the requesting clinician, you should also look at your
patient’s study (at least plain films), as well as follow up on
the final report.
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PTX, PNA, pleural effusions, SBO, free air
Evaluate lines and tubes (especially the ones you placed!)
I: Basics/Hi-Yield:
Looking at Imaging Studies:
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PACS workstations (diagnostic versus
clinical)
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Picture Archiving and Communications System
Radiology, ER, ICU’s, some surgery clinics
Web based PACS (web 1000)
WebCIS based PACS (java script)
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At UNC: “6-PACS” is PACS help desk
I: Basics/Hi-Yield:
tunneled versus non-tunneled catheters
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First, examine the patient!
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A tunnel is a short (several inches) segment of catheter that
is within the superficial soft tissues (subcutaneous fat)
between the venotomy site and the catheter access site.
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Inspect
Palpate
(Don’t auscultate or percuss)
“Perm Caths”
“PortaCaths”
“Powerlines”
A tunnel or port pocket infection usually means removal of
the line.
CVAD= central venous access device
I: Basics/Hi-Yield:
tunneled versus non-tunneled catheters
I: Basics/Hi-Yield:
tubes & drains (abscesses, G-, Neph-)
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Most VIR drains/tubes need to be flushed with sterile saline.
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Nephrostomy and Gastrostomy tubes need to be changed
every 3 months or so.
Abscess drains usually need a sinogram (tube injection) to
evaluate the cavity size and for any fistulous connections,
about 2 weeks after placement.
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The purpose of this is simply to keep the tubes from getting
clogged. All tubes should be flushed after use.
There’s usually a 3-way stopcock to accomplish this.
If cavity small and output of drain is low, then drain may be pulled.
If it’s pulled too early, then the abscess will fester/return.
Surgical drains are managed by the surgical teams, and often
do not need to be flushed (no 3-way stopcock).
II: Obtaining a Radiology Consult
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A Radiology consult is obtained every time
a study is requested!
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Who handles these requests and reads
these studies and/or performs these
procedures?
II: Obtaining a Radiology Consult
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The Department of Radiology at the University of North
Carolina at Chapel Hill has eight clinical sections:
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Abdominal Imaging (Body CT, US, MRI, Flouro studies such as
UGI and SBFT, Biopsies)
Breast Imaging
Cardiopulmonary Imaging (Chest, Cardiac)
Musculoskeletal Imaging (Bone, ER RR, MSK MRI’s)
Neuroradiology (brain/spine CT & MRI; lumbar punctures)
Nuclear Medicine (wide variety, PET-CT, bone scans, Cards)
Pediatric Imaging (wide variety)
Vascular-Interventional (wide variety)
II: Obtaining a Radiology Consult
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6-1461- The Radiology “Front Desk”
Reading rooms (RR’s):
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Body CT 3-2938
Chest 3-2939
GI/Adult Flouroscopy 3-2961
Neuroradiology 3-2978
Pediatrics 6-7554
MSK/bone 6-8850
US 6-0038
MRI 6-8112
Mammography 6-6392
Nuclear medicine 3-2937
VIR 6-4645
The Face of Radiology
II: Obtaining a Radiology Consult (at
UNC Hospitals)
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Try to call the right reading room (RR).
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When you call, identify yourself, and expect whoever answers to identify themselves.
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Improves accountability
Good policy to know who you talked to (always)
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When paging, it’s nice to put your name/pager number immediately after
the call back number
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After hours:
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6-8850 Lower Level/ER RR
216-2826 Upper Level (VIR, Doppler US, MRI)
DON’T call 6-8850 during the day
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unless it’s an MSK radiology issue
II: Obtaining a Radiology Consult:
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VIR or any other invasive procedures:
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Who gives consent? Pleae get phone number of HC POA or
spouse or relative
Basics for any invasive procedure
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See the patient!
Coags (PT, PTT, INR)
Platelets
NPO for sedation or GA
Don’t promise the Bx/Line/procedure, but please tell the patient
before we get there…..
Don’t promise sedation (but we almost always use it)
Think about risks/benefits prior to considering invasive or
expensive procedures. Ask yourself if the results will change
management.
Please page us if our report is confusing!
III: Plain film imaging of the abdomen
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Stones
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Bones
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Lumbar spine, pelvis, hips
Masses
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Gallstones
Renal stones
Organomegaly, ascites
Gasses
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3 cm small bowel
6 cm large bowel
9 cm cecum
III: Plain film imaging of the abdomen
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KUB (kidneys, ureters, bladder)
2 View---AP supine and erect abdomen
Acute abdomen series: 2 view with upright
chest
Lateral decubitus (Left or Right)
Cross table lateral---prone or supine
III: Plain film imaging of the
abdomen: normal supine KUB
III: Plain film imaging of the
abdomen: Gallstones supine and erect
III: Plain film imaging of the
abdomen: Gallstones
III: Plain film imaging of the
Abdomen: Nephrolithiasis
III: Plain film imaging of the
Abdomen: Nephrolithiasis
III: Plain film imaging of the
Abdomen: Bones
III: Plain film imaging of the
abdomen: ascites
III: Plain film imaging of the
abdomen: gasses?
III: Plain film imaging of the
abdomen: gasses? This is SBO
III: Plain film imaging of the
abdomen: more gas & SBO easy to Dx
III: Plain film imaging of the
abdomen: more gas & SBO easy to Dx
III: Plain film imaging of the
abdomen: Pneumoperitoneum
III: Plain film imaging of the
abdomen: Pneumoperitoneum
IV: A Few Random Parting thoughts
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Patients want a doctor who cares about them. When admitting a
patient, get their (family’s) phone numbers yourself, as part of the
History and Physical.
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Learn to take ownership of your patient’s and their medical
problems.
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Patients will forgive you for a host of small things if you show them that you
care, will be honest with them, you will work hard for them over the long
term.
Getting their phone numbers show you care about them and their family.
Follow up on test/imaging results.
Follow up on clinical outcomes.
Longitudinal data is often the most valuable information there is.
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“Old is gold.”- in reference to getting prior imaging studies.
Serial KUB’s and serial exams is often more clinically relevant than getting
a CT scan.
Thanks for listening!
Hx: Please
Evaluate
New Line.
“?!@#!%!”