Incidental Findings in Neuroimaging and Their Management: A Guide for Radiologists, Neurosurgeons, and Neurologists

Incidental Findings in Neuroimaging and Their Management
Title Page
Copyright
Contents
Preface
Contributors
Section I Normal Variants
	1. Persistent Primitive Trigeminal Artery
		1.1 Case Presentation
			1.1.1 History and Physical Examination
		1.2 Differential Diagnosis
		1.3 Diagnostic Pearls and Pitfalls
		1.4 Essential Information about Persistent Primitive Trigeminal Arteries
	2. Arachnoid Granulations
		2.1 Case Presentation
			2.1.1 History and Physical Examination
			2.1.2 Imaging Findings and Impression
		2.2 Differential Diagnosis
		2.3 Diagnostic Pearls and Pitfalls
		2.4 Essential Information about Arachnoid Granulations
		2.5 Companion Case
			2.5.1 History and Physical Examination
	3. Asymmetry of the Lateral Ventricles
		3.1 Case Presentation
			3.1.1 History and Physical Examination
			3.1.2 Imaging Findings and Impression
		3.2 Differential Diagnosis
		3.3 Diagnostic Pearls
		3.4 Essential Information about Asymmetric Lateral Ventricles
		3.5 Companion Case
			3.5.1 History and Physical Examination
			3.5.2 Imaging Findings and Impression
	4. Basal Ganglia/Dentate Nuclei Mineralization
		4.1 Case Presentation
			4.1.1 History and Physical Examination
			4.1.2 Imaging Findings and Impression
		4.2 Differential Diagnosis
		4.3 Diagnostic Pearls
		4.4 Essential Information about Basal Ganglia Mineralization
		4.5 Companion Case
			4.5.1 History and Physical Examination
			4.5.2 Imaging Findings and Impression
	5. Cavum Septum Pellucidum
		5.1 Case Presentation
			5.1.1 History and Physical Examination
			5.1.2 Imaging Findings and Impression
		5.2 Differential Diagnosis
		5.3 Diagnostic Pearls
		5.4 Essential Information about Cavum Septum Pellucidum
		5.5 Companion Cases
			5.5.1 Companion Case 1
			5.5.2 Companion Case 2
	6. Choroid Fissure Cyst
		6.1 Case Presentation
			6.1.1 History and Physical Examination
			6.1.2 Imaging Findings and Impression
		6.2 Differential Diagnosis
		6.3 Diagnostic Pearls
		6.4 Essential Information about Choroid Fissure Cyst
	7. Empty Sella Configuration
		7.1 Case Presentation
			7.1.1 History and Physical Examination
			7.1.2 Imaging Findings and Impression
		7.2 Differential Diagnosis
		7.3 Diagnostic Pearls
		7.4 Essential Information about Empty Sella
	8. High-Riding Jugular Bulb
		8.1 Case Presentation
			8.1.1 History and Physical Examination
			8.1.2 Imaging Findings and Impression
		8.2 Differential Diagnosis
		8.3 Diagnostic Pearls
		8.4 Pitfalls
		8.5 Essential Information about High-Riding Jugular Bulb
		8.6 Companion Case
			8.6.1 History and Physical Examination
			8.6.2 Imaging Findings and Impression
	9. Hyperostosis Frontalis Interna
		9.1 Case Presentation
			9.1.1 History and Physical Examination
			9.1.2 Imaging Findings and Impression
		9.2 Differential Diagnosis
		9.3 Diagnostic Pearls
		9.4 Essential Information about Hyperostosis Frontalis Interna
		9.5 Companion Case
			9.5.1 History and Physical Examination
			9.5.2 Imaging Findings and Impression
	10. Prominent Perivascular Space
		10.1 Case Presentation
			10.1.1 History and Physical Examination
			10.1.2 Imaging Findings and Impression
		10.2 Differential Diagnosis
		10.3 Diagnostic Pearls
		10.4 Pitfalls
		10.5 Essential Information about Prominent Perivascular Space
		10.6 Companion Case
			10.6.1 Imaging Findings and Impression
	11. Simple Pineal Cyst
		11.1 Case Presentation
			11.1.1 History and Physical Examination
			11.1.2 Imaging Findings and Impression
		11.2 Differential Diagnosis
		11.3 Diagnostic Pearls
		11.4 Essential Information about Simple Pineal Cyst
		11.5 Companion Case
			11.5.1 History and Physical Examination
			11.5.2 Imaging Findings and Impression
Section II Intracranial Incidental Findings
	12. Diffuse White Matter Hyperintensities
		12.1 Introduction
		12.2 Case Presentation
			12.2.1 History
		12.3 Imaging Analysis
			12.3.1 Imaging Findings and impression
			12.3.2 Additional Imaging Recommended
		12.4 Clinical Evaluation
			12.4.1 Neurologist History and Physical Examination
			12.4.2 Recommended Additional Testing
			12.4.3 2015 MAGNIMS Standardized Brain and Spine MRI Protocol
			12.4.4 Results of Additional Testing
			12.4.5 Clinical Impression
			12.4.6 Management Decision in This Case
		12.5 Differential Diagnosis of White Matter Lesions
		12.6 Diagnostic Imaging Pearls
		12.7 Clinical and Diagnostic Imaging Pitfalls
		12.8 Companion Cases
			12.8.1 Companion Case 1
			12.8.2 Companion Case 2
			12.8.3 Companion Case 3
		12.9 Clinical and Diagnostic Imaging Pearls: "MS-Like lesions" versus Hypoxic-Ischemic Lesions
		12.10 Essential Information about Leukoaraiosis ("Age-Related" White Matter Changes and Small-Vessel Ischemic Disease)
		12.11 Clinical Questions and Answers with a Neurologist about Radiologically Isolated Syndrome
		12.12 Key Point Summary
	13. Brain Capillary Telangiectasias
		13.1 Introduction
		13.2 Case Presentation
		13.3 Imaging Analysis
			13.3.1 Imaging Findings
		13.4 Clinical Evaluation and Management
		13.5 Differential Diagnosis
		13.6 Diagnostic Imaging Pearls
		13.7 Essential Facts about BCTs
		13.8 Companion Cases
			13.8.1 Companion Case 1: Breast Cancer Metastases
			13.8.2 Companion Case 2: Recent (Subacute) Pontine Infarct
			13.8.3 Companion Case 3: Active Pontine Demyelination
			13.8.4 Companion Case 4: CLIPPERS (Chronic Lymphocytic Inflammation with Pontine Perivascular Enhancement Responsive to Steroids)
			13.8.5 Companion Case 5: Capillary Telangiectasia
		13.9 Questions and Answers
		13.10 Key Point Summary
	14. Developmental Venous Anomaly
		14.1 Introduction
		14.2 Case Presentation
		14.3 Imaging Analysis
			14.3.1 Imaging Findings
			14.3.2 Impression
		14.4 Clinical Evaluation
		14.5 Differential Diagnosis
			14.5.1 Diagnostic Imaging and Clinical Pearls
		14.6 Essential Imaging Facts about DVAs
		14.7 Companion Cases
			14.7.1 Companion Case 1
			14.7.2 Companion Case 2
		14.8 Questions and Answers
		14.9 Key Point Summary
	15. Cerebral Cavernous Malformations
		15.1 Introduction
		15.2 Case Presentation
		15.3 Imaging Analysis
			15.3.1 Imaging Findings
			15.3.2 Additional Imaging
			15.3.3 Imaging Findings
			15.3.4 Impression
		15.4 Differential Diagnosis
		15.5 Diagnostic Imaging Pearls
		15.6 Clinical Evaluation and Management
			15.6.1 Neurosurgical Evaluation
			15.6.2 Essential Diagnostic Imaging Information Regarding Cavernous Malformations
		15.7 Companion Cases
			15.7.1 Companion Cases 1 and 2: Diffuse Axonal Injury
			15.7.2 Companion Case 3: Amyloid Angiopathy
			15.7.3 Companion Case 4: Hemorrhagic Metastatic Disease
			15.7.4 Companion Case: Classic "Popcorn" Appearance of CCM
		15.8 Neurosurgery Questions and Answers
		15.9 Key Point Summary
	16. Colloid Cyst
		16.1 Introduction
		16.2 Case presentation
			16.2.1 Clinical History
		16.3 Imaging Analysis
			16.3.1 Imaging Findings
			16.3.2 Additional Imaging Performed
		16.4 Clinical Evaluation
			16.4.1 Neurosurgery Evaluation
			16.4.2 Clinical Management
		16.5 Differential Diagnosis for Masses in the Region of the Foramen of Monro
		16.6 Pearls and Pitfalls
		16.7 Essential Facts about Colloid Cysts
			16.7.1 Key Components of the Radiologist's Report
			16.7.2 Imaging Features of Colloid Cysts
			16.7.3 Third Ventricular "Risk" Zones
		16.8 Companion Cases
			16.8.1 Companion Cases Demonstrating Variable Appearances of Third Ventricular Colloid Cysts
			16.8.2 Companion Cases of Entities Which May Mimic Third Ventricular Colloid Cysts
		16.9 Neurosurgery Questions and Answers
	17. Arachnoid Cysts
		17.1 Case Presentation
			17.1.1 History and Physical Examination
		17.2 Imaging Analysis
			17.2.1 Imaging Findings and Impression
			17.2.2 Imaging Guidelines
		17.3 Clinical Evaluation and Management
		17.4 Differential Diagnosis
		17.5 Diagnostic Pearls
		17.6 Essential information about arachnoid cysts
			17.6.1 Etiology
			17.6.2 Galassi Classification
		17.7 Companion Case
			17.7.1 History
			17.7.2 Imaging Findings and Impression
			17.7.3 Neurosurgical Consultation
		17.8 Neurosurgery Questions and Answers
	18. Mega Cisterna Magna
		18.1 Case Presentation
			18.1.1 History
		18.2 Imaging Analysis
			18.2.1 Imaging Findings and Impression
		18.3 Differential Diagnosis
		18.4 Diagnostic Pearls
		18.5 Essential Information about Mega Cisterna Magna
		18.6 Companion Case
		18.7 Neurosurgery Questions and Answers
	19. Benign Enlargement of Subarachnoid Spaces
		19.1 Case Presentation
			19.1.1 History
		19.2 Imaging Analysis
			19.2.1 Imaging Findings and Impression
		19.3 Differential Diagnosis
		19.4 Diagnostic Pearls
		19.5 Essential information about Benign Enlargement of Subarachnoid Spaces
		19.6 Companion Case
			19.6.1 Benign Enlargement of Subarachnoid Spaces versus Chronic Subdural Hematomas
		19.7 Neurosurgery Questions and Answers
	20. Pituitary Incidentaloma and Incidental Silent Macroadenoma
		20.1 Pituitary Incidentaloma
			20.1.1 Introduction
			20.1.2 Case Presentation
			20.1.3 Imaging Analysis
			20.1.4 Clinical Evaluation
			20.1.5 Imaging Differential Diagnosis of Intrasellar Lesions
			20.1.6 Diagnostic Imaging Pearls
			20.1.7 Diagnostic Imaging Pitfalls: Artifacts and "Overcalls"
			20.1.8 Additional Information Regarding Pituitary Lesion Imaging
			20.1.9 Companion Cases
		20.2 Incidental Silent Macroadenoma
			20.2.1 Introduction
			20.2.2 Case Presentation
			20.2.3 Imaging Analysis
			20.2.4 Clinical Evaluation
			20.2.5 Differential Diagnosis of Sellar/Parasellar Masses
			20.2.6 Diagnostic Imaging and Clinical Pearls and Pitfalls
			20.2.7 Companion Case
			20.2.8 Neurosurgery and Endocrinology Questions and Answers
		20.3 Key Point Summary
	21. Pituitary Gland: Diffuse Enlargement
		21.1 Introduction
		21.2 Case Presentation
			21.2.1 History
		21.3 Imaging Analysis
			21.3.1 Imaging Findings and Impression
			21.3.2 Additional Imaging Recommended
		21.4 Clinical Evaluation
			21.4.1 Endocrinologist Evaluation
			21.4.2 Recommended Laboratory Testing and Results
			21.4.3 Clinical Impression
			21.4.4 Recommendations
		21.5 Differential Diagnosis of Diffuse Enlargement of the Pituitary Gland
		21.6 Clinical and Diagnostic Imaging Pearls
		21.7 Companion Cases
			21.7.1 Companion Case 1
			21.7.2 Companion Case 2
			21.7.3 Companion Case 3
		21.8 Neurosurgery and Endocrinology Questions and Answers
		21.9 Key Point Summary
	22. Incidental Glial Neoplasms
		22.1 Introduction
		22.2 Case Presentation
			22.2.1 History and Physical Examination
			22.2.2 Imaging Findings and Impression
			22.2.3 Additional Imaging
		22.3 Clinical Evaluation
			22.3.1 Clinical Impression and Management
		22.4 Differential Diagnosis
		22.5 Clinical and Diagnostic Imaging Pearls and Pitfalls
		22.6 Essential Facts about Gliomas
		22.7 Clinical Relevance of Genomic Alterations and Correlation with Conventional and Advanced Imaging Techniques
			22.7.1 Isocitrate Dehydrogenase Mutations in Gliomas
			22.7.2 1p19q Codeletion, IDH Mutated ("Oligodendroglioma Phenotype")
			22.7.3 ATRX Mutated, 1p19q Intact, IDH Mutated ("Diffuse Astrocytoma Phenotype")
			22.7.4 IDH-Mutated GBM ("Secondary GBM Phenotype")
			22.7.5 IDHwt GBM ("Primary GBM Phenotype")
			22.7.6 MGMT promoter methylation
		22.8 Companion Case
			22.8.1 History and Physical Examination
			22.8.2 Imaging Analysis
			22.8.3 Clinical Evaluation
		22.9 Neurosurgery Questions and Answers
		22.10 Key Point Summary
	23. Incidental Meningioma
		23.1 Introduction
		23.2 Case Presentation
			23.2.1 History and Physical Examination
			23.2.2 Imaging Findings
			23.2.3 Additional Tests to Consider
		23.3 Neurosurgical Consultation
		23.4 Differential Diagnosis of Dural Based Masses
		23.5 Diagnostic Pearls and Pitfalls
		23.6 Companion Case
			23.6.1 History
			23.6.2 Imaging Description and Impression
			23.6.3 Neurosurgery Consultation
		23.7 Neurosurgery Questions and Answers
		23.8 Key Point Summary
Section III Head and Neck-Associated Incidental Findings
	24. Head and Neck-Related Incidental Findings
		24.1 Parotid Mass
			24.1.1 Case Presentation
			24.1.2 Clinical Evaluation
			24.1.3 Differential Diagnosis
			24.1.4 Clinical and Diagnostic Imaging Pearls and Pitfalls
			24.1.5 Essential Facts
		24.2 Thyroglossal Duct Cyst
			24.2.1 Case Presentation
			24.2.2 Clinical Evaluation
			24.2.3 Differential Diagnosis
			24.2.4 Imaging Pearls and Pitfalls
			24.2.5 Essential Facts
		24.3 Prominent Nasopharyngeal Soft Tissue
			24.3.1 Case Presentation
			24.3.2 Clinical Management
			24.3.3 Differential Diagnosis
			24.3.4 Imaging Pearls and Pitfalls
			24.3.5 Essential Facts
		24.4 Incidental Enlarged Lymph Node
			24.4.1 Case Presentation
			24.4.2 Clinical Management
			24.4.3 Differential Diagnosis
			24.4.4 Imaging Pearls and Pitfalls
			24.4.5 Essential Facts
		24.5 Key Point Summary
Section IV Spinal Incidental Findings
	25. Os Odontoideum
		25.1 Introduction
		25.2 Case Presentation
			25.2.1 History and Physical Examination
			25.2.2 Imaging Findings and Impression
			25.2.3 Additional Imaging to Be Considered for Further Evaluation
		25.3 Clinical Evaluation
		25.4 Differential Diagnosis
		25.5 Clinical and Diagnostic Imaging Pearls
		25.6 Essential Information about the Os Odontoideum
			25.6.1 Embryology of C2 and Its Odontoid Process
			25.6.2 Os Odontoideum: Classification Schemes
			25.6.3 Controversial Etiology
		25.7 Companion Cases
			25.7.1 Case 1: Type 2 Odontoid Fracture
			25.7.2 Case 2: Chronic Odontoid Fracture with Nonunion
			25.7.3 Case 3: Os Terminale Persistens
			25.7.4 Case 4: Os Odontoideum versus Large Os Terminale
			25.7.5 Case 5: Os Odontoideum
			25.7.6 Case 6: Massive "Os Odontoideum"
			25.7.7 Case 7: Basilar Process Mimicking a Condylus Tertius
			25.7.8 Case 8: Dystrophic Ossification in the Region of the Dens
		25.8 Neurosurgery Questions and Answers
		25.9 Key Point Summary
	26. Tarlov's Cyst
		26.1 Introduction
		26.2 Case Presentation
			26.2.1 History and Physical Examination
			26.2.2 Imaging Analysis
		26.3 Clinical Evaluation
		26.4 Differential Diagnosis
		26.5 Diagnostic Pearls
		26.6 Essential Information about Spinal Meningeal Cysts
		26.7 Companion Case
			26.7.1 History and Physical Examination
			26.7.2 Imaging Analysis
			26.7.3 Clinical Evaluation
		26.8 Neurosurgery Questions and Answers
	27. Approach to the Solitary Vertebral Lesion on Magnetic Resonance Imaging
		27.1 Introduction
		27.2 Case Presentation
			27.2.1 History and Physical Examination
			27.2.2 Imaging Analysis
		27.3 Recommended Management
		27.4 Differential Diagnosis for a Focal Vertebral Lesion on MRI That Is Hyperintense T1-Weighted Images
		27.5 Clinical and Diagnostic Imaging Pearls: An Approach to the Solitary Vertebral Lesion Detected Incidentally on MRI
		27.6 Essential Facts about Hemangiomas
			27.6.1 Demographics
			27.6.2 Imaging Appearance
		27.7 Companion Cases
			27.7.1 Companion Case 1: Typical Hemangioma
			27.7.2 Companion Case 2: Aggressive Hemangioma
			27.7.3 Companion Case 3: Intraosseous lipoma
			27.7.4 Companion Case 4: Atypical Hemangioma
			27.7.5 Companion Case 5: Focal Red Marrow
			27.7.6 Companion Case 6: Appearance of a Typical Hemangioma on Fat-Suppressed T2W Images
	28. Diffusely Abnormal Marrow Signal within the Vertebrae on MRI
		28.1 Introduction
		28.2 Diffuse Abnormal Marrow: Normal Variant
			28.2.1 Case Presentation
			28.2.2 Imaging Findings and Impression
			28.2.3 Additional Testing Options
			28.2.4 Clinical Evaluation
			28.2.5 Differential Diagnosis of Diffuse, Heterogeneous Marrow Signal
			28.2.6 Essential Information regarding Bone Marrow Signal on MRI
			28.2.7 Pearls and Pitfalls in Interpretation of Bone Marrow Signal on MRI
			28.2.8 Companion Case: Examples of Adult Normal Bone Marrow on MRI
		28.3 Diffuse Bone Marrow Signal Abnormality: Hairy Cell Leukemia
			28.3.1 Case Presentation
			28.3.2 Imaging Findings and Impression
			28.3.3 Clinical Evaluation
			28.3.4 Differential Diagnosis of the Most Common Causes of Diffuse Abnormality of the Bone Marrow Signal (Hypointense on T1WIs)
			28.3.5 Essential Information regarding Hairy Cell Leukemia
		28.4 Multiple Myeloma
			28.4.1 Case Presentation
			28.4.2 Imaging Findings
			28.4.3 Clinical Evaluation
			28.4.4 Differential Diagnosis of Multifocal Vertebral Lesions
			28.4.5 Pearls and Pitfalls of Imaging Interpretation in Multiple Myeloma
			28.4.6 Essential Clinical and Imaging Information Regarding Multiple Myeloma
	29. Filum Terminale Lipoma
		29.1 Case Presentation
			29.1.1 History
		29.2 Imaging Analysis
		29.3 Differential Diagnosis
		29.4 Diagnostic Pearls
		29.5 Essential Information about Filum Terminale Lipoma
		29.6 Neurosurgery Questions and Answers
	30. Ventriculus Terminalis
		30.1 Case Presentation
		30.2 Imaging Analysis
		30.3 Differential Diagnosis
		30.4 Diagnostic Pearls
		30.5 Essential Information about Ventriculus Terminalis
			30.5.1 Etiology
			30.5.2 Imaging Pitfalls
			30.5.3 Follow-up
		30.6 Neurosurgery Questions and Answers
	31. Prominent Central Canal
		31.1 Case Presentation
		31.2 Imaging Analysis
		31.3 Differential Diagnosis
		31.4 Diagnostic Pearls
		31.5 Essential Information about Prominent Central Canal
			31.5.1 Etiology
			31.5.2 Imaging Pitfalls
			31.5.3 Follow-up
		31.6 Neurosurgery Questions and Answers
	32. Low-Lying Conus
		32.1 Case Presentation
		32.2 Imaging Analysis
		32.3 Differential Diagnosis
		32.4 Imaging Pearls
		32.5 Essential Information about Low-Lying Conus
			32.5.1 Etiology
			32.5.2 Imaging Pitfalls
			32.5.3 Follow-up
		32.6 Neurosurgery Questions and Answers
	33. Incidental Solitary Sclerotic Bone Lesion
		33.1 Introduction
		33.2 Case Presentation
		33.3 Imaging Analysis
		33.4 Clinical Evaluation and Management
		33.5 Imaging Differential Diagnosis
		33.6 Distinguishing a Bone Island from a Solitary Sclerotic Metastasis: Diagnostic Imaging Pearls
		33.7 Clinical Pearls
		33.8 Essential Information about Bone Islands
		33.9 Companion Cases
			33.9.1 Case 1: Typical Bone Island on CT and MRI
			33.9.2 Case 2: Solitary Prostate Cancer Metastasis
			33.9.3 Case 3: Benign Notochordal Cell Tumor
		33.10 Key Point Summary
Section V Extraspinal Incidental Findings
	34. Abdominal Aortic Aneurysm
		34.1 Case 1
			34.1.1 History
			34.1.2 Imaging Findings
			34.1.3 Impression
			34.1.4 Additional Testing Needed and Rationale
			34.1.5 Management Decision
		34.2 Case 2
			34.2.1 History
			34.2.2 Imaging Findings
			34.2.3 Impression
			34.2.4 Additional Evaluation Needed and Rationale
			34.2.5 Management Decision
		34.3 Differential Diagnosis
		34.4 Diagnostic Imaging Pearls and Pitfalls
		34.5 Essential Additional Information about Abdominal Aortic Aneurysms
		34.6 Key Point Summary
	35. Renal Mass
		35.1 Case 1
			35.1.1 Imaging Impression
			35.1.2 Diagnostic Testing Needed
			35.1.3 Imaging Interpretation
		35.2 Case 2
			35.2.1 Imaging Impression
			35.2.2 Additional Testing Needed
			35.2.3 Imaging Interpretation
		35.3 Differential Diagnosis
		35.4 Diagnostic Pitfalls and Pearls
		35.5 Essential Facts about Renal Masses Detected Incidentally on MRI
	36. Renal Cyst
		36.1 Case Presentation
		36.2 Diagnostic Testing Needed
		36.3 Imaging Diagnosis
		36.4 Diagnostic Pitfalls and Pearls
		36.5 Management of Incidentally Identified Renal Cysts by MR Imaging
	37. Thyroid Mass
		37.1 Case 1
			37.1.1 Imaging Impression
			37.1.2 Additional Testing Needed: Thyroid Ultrasound
			37.1.3 Imaging Interpretation
		37.2 Case 2
			37.2.1 Imaging Impression
			37.2.2 Additional Testing Needed
			37.2.3 Imaging Impression
		37.3 Diagnostic Pearls and Pitfalls
		37.4 Essential Facts about Thyroid Nodules Detected Incidentally on MRI
	38. Adrenal Mass
		38.1 Case 1
			38.1.1 Imaging Impression
			38.1.2 Additional Testing Needed
			38.1.3 Imaging Impression
		38.2 Case 2
			38.2.1 Imaging Impression
			38.2.2 Additional Testing Needed
			38.2.3 Imaging Impression
		38.3 Case 3
			38.3.1 Imaging Impression
		38.4 Diagnostic Pearls and Pitfalls
		38.5 Essential Facts about Adrenal Incidentalomas Detected on MRI
		38.6 Key Point Summary
	39. Retroperitoneal Lymph Nodes
		39.1 Case 1
			39.1.1 History
			39.1.2 Most Likely Imaging Diagnosis for Case 1
		39.2 Case 2
			39.2.1 History
			39.2.2 Most Likely Imaging Diagnosis for Case 2
		39.3 Differential Considerations and Diagnostic Checklist
		39.4 Additional Essential Information Regarding Incidentally Detected"Lymphadenopathy"
			39.4.1 Definitions and Key Facts
			39.4.2 Imaging and Workup
		39.5 Key Point Summary
	40. Incidental Pelvic Mass
		40.1 Case Presentation
		40.2 Imaging Findings and Impression
			40.2.1 Additional Testing Needed
			40.2.2 Pelvic Ultrasound Findings and Impression
		40.3 Essential Information regarding Ovarian Serous Cystadenomas
		40.4 Essential Information about Incidental Pelvic Masses Detected on Lumbosacral MRI or CT
		40.5 Key Point Summary
Section VI Artifacts That May Obscure Pathology and Simulate Disease Entities
	41. Computed Tomography Artifacts
		41.1 Computed Tomography Angiography
			41.1.1 Case Presentation: CTA Artifacts Mimicking Carotid Artery Dissection
			41.1.2 Companion Cases
			41.1.3 Case Presentation: CTA Artifact Mimicking Partial Basilar Artery Thrombosis
		41.2 Beam Hardening Artifact Mimics a Brain Tumor
		41.3 Ring Detector Artifact Simulates a Mass in the Basal Ganglia
	42. MRI Patient-Related Motion Artifacts
		42.1 Cerebrospinal Fluid Flow Artifacts
			42.1.1 Case Presentation
			42.1.2 Differential Diagnosis
			42.1.3 Differential Diagnostic Pearls and Pitfalls
			42.1.4 Artifact Problem-Solving: Additional Evaluation Recommended in Difficult Cases
			42.1.5 Essential Information:
			42.1.6 Companion Case
		42.2 Pulsatile Motion Artifact
			42.2.1 Case Presentation
			42.2.2 Artifact Problem-Solving: Additional Evaluation or Sequence Modifications Recommended in Difficult Cases
			42.2.3 Essential Information: Motion Artifact on MRI Creating Pseudo-Lesions
			42.2.4 Companion Case
		42.3 Slow Flow in Vessels Creating Artifactson MRI
			42.3.1 Case Presentation
			42.3.2 Differential Diagnostic Pearls
			42.3.3 Artifact Problem-Solving: Additional Evaluation to Consider in Difficult Cases
			42.3.4 Essential Facts: Artifacts Produced by Flowing Blood on MRI
			42.3.5 Companion Cases
		42.4 Random Patient Motion
			42.4.1 Case Presentation
	43. Magnetic Susceptibility-Related Artifacts on MRI
		43.1 General Magnetic Susceptibility-Related Artifacts
			43.1.1 Case 1 Presentation
			43.1.2 Imaging Findings
			43.1.3 Essential Facts about Magnetic Susceptibility Artifacts in MR Imaging
			43.1.4 Companion Cases
		43.2 Vascular Stent Artifacts
			43.2.1 History
			43.2.2 Imaging Findings
			43.2.3 Differential Diagnosis
			43.2.4 Imaging Impression
			43.2.5 Essential Information regarding Stent-Related Artifacts
			43.2.6 Common Artifactual Phenomenon Simulating Abnormalities on 2D TOF MRA
			43.2.7 Companion Cases
	44. MRI Technical and Sequence-Specific Artifacts
		44.1 Pulse Sequence-Specific Artifacts: FLAIR
			44.1.1 Case 1 Presentation
			44.1.2 Imaging Findings
			44.1.3 Differential Diagnosis of Subarachnoid FLAIR Hyperintensity
			44.1.4 Pearls and Pitfalls of FLAIR Imaging
			44.1.5 Essential Facts about FLAIR Imaging
			44.1.6 Companion Cases
			44.1.7 Case 2 Presentation
			44.1.8 Imaging Findings
			44.1.9 Differential Diagnosis
			44.1.10 Essential Information regarding the T1W-FLAIR Sequence
			44.1.11 Companion Case
		44.2 Hardware/Room-Related MR Artifacts
			44.2.1 Case 1 Presentation
			44.2.2 Imaging Findings
			44.2.3 Companion Case 1
			44.2.4 Companion Case 2
			44.2.5 Imaging Findings
		44.3 Nonspecific Pulse Sequence Technical Artifacts: Wraparound Artifact with and without the Use of Parallel Imaging Techniques
			44.3.1 Case 1 Presentation
			44.3.2 Imaging Findings
			44.3.3 Essential Information regarding Wraparound Artifact
			44.3.4 Companion Case
			44.3.5 Imaging Findings
			44.3.6 Essential Information about Parallel Imaging and Reconstruction Artifacts
			44.3.7 Companion Case 1
			44.3.8 Companion Case 2
Index