introduction to radiology michael solle, md, phd

Introduction to Radiology

Michael Solle, MD, PhD

Introduction to Radiology I: Radiology Basics and High Yield Topics

Modalities in Radiology and Cases Contrast How to look at studies Catheters: tunneled vs non-tunneled Drains and Tubes

II: How to Consult Radiology III: Plain Film Imaging of the Abdomen IV: Parting Thoughts

Dr. Molina and Chest Radiology

Definition of Radiology Radiology is a medical

specialty using medical imaging technologies to diagnose and treat patients.

I: Basics/Hi-Yield:Radiology Modalities Conventional radiographs (“x-rays”)

Fluoroscopy Mammography

Computed Tomography (CT) Nuclear Medicine (NM)

PET-CT combines CT and NM

Ultrasound (US) Magnetic resonance imaging (MRI)

Radiology Modalities Conventional

Radiography Lingo:

Density Opacity

Observable Densities: Metal Bone Soft Tissue Gas

Radiology Modalities Fluoroscopy

“Live” imaging Contrast agents often

given

Radiology Modalities Computed Tomography

Lingo: Attenuation Density Enhancement

Hounsfield Units -1000 air *** -100 fat 0 water *** 20-80 soft tissues 100’s bone/Ca/contrast >1000’s metal

Large radiation dose

Radiology Modalities Nuclear Medicine

Lingo: Counts or Activity

Physiologic imaging Radionuclides

Technetium Radiopharmaceuticals

“Choletec” Radioactivity stays with

the patient until cleared or decayed

Radiology Modalities Ultrasound

Lingo Echogenicity Shadowing Doppler for flow

No radiation Can be portable Relatively inexpensive

Radiology Modalities MRI

Lingo: Signal intensity T1 T2 Enhancement

No radiation Strong magnetic field

No pacemakers No electronic implants

Small, loud tube and patients must be able to hold still

Relatively expensive

Radiology Modalities: 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:

Conventional radiographs (“x-rays”): Great place to start (cheap, fast, low radiation).

Computed Tomography (CT): Diagnostic dilemmas (pricier, variable speed b/c of contrast). High radiation.

Nuclear Medicine Physiological imaging, great for specific questions.

Ultrasound (US) Relatively inexpensive, and no radiation. Highly dependent on patient’s body size and US operator.

Magnetic resonance imaging (MRI) Relatively expensive, no radiation, not fast. Unmatched ability to contrast healthy tissue from disease.

I: Basics/Hi-Yield:A few words on contrast CT contrast:

IV- contains Iodine; which attenuates x-rays 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: IV- contains gadolinium chelated to a carrier molecule; acts as a

paramagnetic molecule which increases signal on T1 images Contraindicated in renal failure (acute and particularly ESRD) b/c of

risk of NSF

I: Basics/Hi-Yield:A few words on contrast AVOIDING CONTRAST IN THE SETTING OF

ACUTE RENAL FAILURE IS DIFFICULT for the radiologist, because the creatinine may be normal.

In hyper-acute renal failure, the creatinine hasn’t risen yet. Decreased urine output or anuria is acute renal failure – regardless of the creatinine.

Remember; first do no harm! Non-contrast studies can often be quite helpful.

I: Basics/Hi-Yield:Looking at Imaging Studies: Adequate Study?

Correctly labeled with patient’s name, MR#, and the date of the study?

Technically adequate? Systematic versus Focused look at a study:

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.

PTX, PNA, pleural effusions, SBO, free air Evaluate lines and tubes (especially the ones you placed!)

I: Basics/Hi-Yield:Looking at Imaging Studies: PACS workstations (diagnostic versus

clinical) Picture Archiving and Communications System Radiology, ER, ICU’s, some surgery clinics

Web based PACS (web 1000) WebCIS based PACS (java script)

At UNC: “6-PACS” is PACS help desk

I: Basics/Hi-Yield:tunneled versus non-tunneled catheters First, examine the patient!

Inspect Palpate (Don’t auscultate or percuss)

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. “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-) Most VIR drains/tubes need to be flushed with sterile saline.

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. 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.

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 A Radiology consult is obtained every time

a study is requested!

Who handles these requests and reads these studies and/or performs these procedures?

II: Obtaining a Radiology Consult The Department of Radiology at the University of North

Carolina at Chapel Hill has eight clinical sections: 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 6-1461- The Radiology “Front Desk” Reading rooms (RR’s):

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) Try to call the right reading room (RR).

When you call, identify yourself, and expect whoever answers to identify themselves. Improves accountability Good policy to know who you talked to (always)

When paging, it’s nice to put your name/pager number immediately after the call back number

After hours: 6-8850 Lower Level/ER RR 216-2826 Upper Level (VIR, Doppler US, MRI)

DON’T call 6-8850 during the day unless it’s an MSK radiology issue

II: Obtaining a Radiology Consult: VIR or any other invasive procedures:

Who gives consent? Pleae get phone number of HC POA or spouse or relative

Basics for any invasive procedure 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 Stones

Gallstones Renal stones

Bones Lumbar spine, pelvis, hips

Masses Organomegaly, ascites

Gasses 3 cm small bowel 6 cm large bowel 9 cm cecum

III: Plain film imaging of the abdomen

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

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.

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.

Learn to take ownership of your patient’s and their medical problems.

Follow up on test/imaging results. Follow up on clinical outcomes.

Longitudinal data is often the most valuable information there is. “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.“?!@#!%!”