Chapter 1: The science and the scan
"Boring, But Necessary"
- Hybrid Imaging System
- Anatomic & Functional Exam
- The Machine
- “Whole Body” vs. “Skull Base to Mid-Thigh”
- Three Sets of Images
Produced
- Glucose Analog
- Malignancy & Glucose Metabolism
- Mechanisms for Increased Intracellular Glucose
- Why 18F-FDG Works
- Whole Body Assessment
- The “You’re Kidding Me!” Effect
- Post-Therapeutic Scar vs. Active Malignancy
- Detecting Malignancy
- Staging Malignancy
- Assess Response to Therapy
- Detecting Recurrence
- Not All Cancer is FDG-Avid
- Normal FDG-Uptake vs. Pathologic Uptake
- Technical Limitations
- Poor Patient Preparation
- Misregistration
- Brown Fat Activation
- SUV Problems
- Fields of View Discrepancy
- PET/CT Artifacts
- Timing of Exam After Therapy
- CT Images
- Non-Attenuation Corrected Images
- Attenuation Corrected Images
- Maximum Intensity Projection (MIP)
- Fusion of Images
- All Images Viewed in 3 Planes
7. Contrast Media: Oral & I.V.
- Who Gets Oral Contrast?
- Who Gets IV Contrast?
- Oral Contrast “Cocktail” Recipe
8. What the Patient Should Expect
- Documenting Height & Weight
- Private Resting Room
- Drinking PO Contrast
- FDG Injection
- Delay Between Injection & Scan
9. Safety Concerns with PET/CT Imaging
- Radiation Exposure to Patient
- Radiation Exposure to Patient’s Contacts
- Patient Contact with Pregnant Women
- Breastfeeding
Chapter 2: PET/CT Problems Which Limit Interpretation
"Something just doesn't seem right here"
- Optimizing Glucose & Insulin Levels
- Fasting Prior to Exam
- Diabetic Patients
- Low Carbohydrate Diet
- Hydration
- Strenuous Exercise
- Voiding Prior to Exam
- Patient Instruction Sheet
- Definition
- Distribution / Appearance
- Don’t Miss the Hidden Nod
- Reporting Language
- Prevention
3. Timing of PET/CT Exam After Therapy
- “Rule of 3”
- Chemotherapy: 1 month
- Surgery: 2 months
- Radiation: 3 months
- Etiology: Hybrid Imaging
- Patient Movement
- Respiratory Motion
- Breathing Techniques
- Bowel Peristalsis
- False Positives
- False Negatives
- Reporting Language
- Beam Hardening
- Diaphragmatic Mismatch
- Linear Hand Motion
- Attenuation Correction
- Differing Fields of View
- Poor Patient Preparation
- FDG Extravasation
- Extensive Brown Fat
- Metformin-Induced Bowel Uptake
- Marked Reactive Marrow Uptake
- Extensive Tumor Uptake in
- Different Types of SUV Measurements
- Factors that Influence SUV Measurements
- What SUV Number Indicates Malignancy?
- What Percent Change in SUV on a Follow Up Exam is Significant?
- How to Compare Exams With Very Different Background Metabolic Activities?
Chapter 3: The Standardized Uptake Value (SUV)
"The good, the bad & the ugly"
1. What is the SUV & Why Used?
- Quantitative vs. Qualitative Assessment
- Unitless Measurement
- Formula
- SUV = ?
- Patient Preparation
- Time Between FDG Injection & Scan
- Partial Volume Effects
- Extravasation
- Patient Weight
- Size & Position of ROI
- Attenuation Correction Artifacts
- Consensus?
- Body Weight
- Lean Body Mass
- Ideal Body Weight
- Body Surface Area
- Maximum vs. Mean
- Average SUV’s by Organ
4. Interpreting the SUV: Threshold Values, “Oncologic Plausibility” & Relative Uptake
- Precise Threshold Values?
- “Oncologic Plausibility”
- Relative Uptake
- Assessing Nodes in Lymphoma Cases
- Assessing Nodes in Non-Lymphoma Cases
- Potential Lesions in Solid Organs
- Pulmonary Nodules
5. What % Change in SUV on a Follow Up Exam is Clinically Significant?
- The Problem
- Current Recommendations
6. How to Compare Sequential Exams With Very Different Background Activities?
- Differing Background Metabolic Activities
- When Qualitative Assessment is Required
- Reporting Language
7. Should We Just Abandon the SUV?
- Pros & Cons
- “Qualitative” Definitions
- Mild
- Moderate
- Intense
- Final Recommendations
Chapter 4: Our Systematic Approach to Reading a PET/CT
"Eat your vegetables"
1. Reading Station & Reading Software
- Reading Station
- Monitor Set-Up
- PET/CT Reading Software
- Hanging Protocol
- Reading in Context (“Oncologic Plausibility”)
- Measure Size on CT, Not on PET Images
- Abnormality Seen Only on First PET Image
- Assess the Patient’s Main Pathology Last
- Beware the Ureter
3. Excellent Views: The MIP, Coronal & Sagittal Images
- 3-D Rotating MIP & Coronal “Quick MIP”
- Coronal PET
- Sagittal PET
4. Written Annotations While Reading
- Numbers, Numbers & More Numbers
- Size & SUV Annotation System
- Sample Annotation Sheet
- Goals of Reporting
- Lawyers, Lawyers & Lawyers
- Sample PET/CT Report
- Negative Exam
- Positive Exam
- Patient Questionnaire
- Technologist’s Data Sheet
- Huge Exam: Requires Systematic Approach
- Our “12-Step Reading System”
- “The Read” in Action: Sample Case (Video)
- Annotations for Sample Case
- Final Report for Sample Case
Chapter 5: Normal Physiologic Distribution of FDG
"The essentials"
- To Locate Cancer, First Eliminate:
- Normal FDG-Avid “Structures”
- Benign FDG-Avid “Findings”
Chapter 6: Benign FDG-Avid "Findings" & Common Diagnostic Challenges
"Separating the Expert from the Not-So-Expert"
3. Chest
- Inflammatory Lymph Nodes
- Thymic Rebound
- Pleura: Talc Pleurodesis vs. Malignancy vs. Inflammation
-
Radiation-Induced Lung Disease
- Radiation Pneumonitis
- Radiation Fibrosis
- "Post-Therapeutic Inflammatory Changes" / Scarring of the Lung
- Atelectasis / Infiltrate
- Lipomatous Hypertrophy of the Inter-Atrial Septum
- Elastofibroma Dorsi
- Site of Prior Chest Port
- Esophagitis vs. Neoplasm
- Subcutaneous & Intramuscular Medical Injections
- Injected FDG-Blood Clot
4. Abdomen & Pelvis
- The Heterogeneous Liver
- Liver Ablation
- Hypermetabolic Geographic Fatty Infiltration
- Hypermetabolic Hepatic Adenoma
- FDG-Avid Adrenal Gland Algorithm
- Therapy-Induced Splenic Activation
- Peritoneal Carcinomatosis
- Pre-Sacral Soft Tissue After Rectal Surgery
- Gallbladder: Cholecystitis vs. Malignancy
- Inguinal Herniorraphy
- Bladder in Inguinal Canal
- Uterine Fibroid
- Tampon
5. Miscellaneous (continued)
-
Vascular Uptake
- Atherosclerosis
- Vasculitis
- Vascular Grafts
-
Value of NAC PET Images
- Resolving AC Artifacts
- Lung Nodule Identification
-
Non-Malignant, Yet Clinically Significant, FDG-Avid CT Abnormalies
- Acute Diverticulitis
- Colitis
- Cholecystitis
- Pneumonia
- Abscess
- Pancreatitis
- Skeletal Abnormalities [See Chapter 7]
Chapter 7: The Bones
"...is connected to the..."
Chapter 8: The Cancers
"Putting it all together"
Inguinal Herniorrhaphy
Special attention to inguinal herniorrhaphy is made here due to the frequency of its misinterpretation by PET/CT radiologists (a general discussion of post-operative inflammatory changes can be found here).
While nearly all post-operative hypermetabolic inflammatory changes in the body resolve within a few months, intense FDG uptake secondary to inguinal herniorrhaphy can persist for many years. Such changes can be seen with or without surgical mesh placement.
Ill-defined and often intensely-avid soft tissue density will be seen in the inguinal region and/or along the most distal aspect of the external iliac chain (within the pelvis), abutting the inguinal region.
Post-herniorrhaphy scar tissue can appear very nodular and very hypermetabolic, inducing considerable anxiety in the inexperienced PET/CT radiologist.
Not infrequently, the metabolic activity of the resulting tissue will fluctuate — decreasing or increasing on a follow-up exam.
