Arachnoid Cysts: State-of-the-Art

Foreword
Contents
Part I: General Information About Arachnoid Cysts
	Editor’s Summary
	History and Etymology of Arachnoid Cysts
		1	 Introduction
		2	 Early History
		3	 Serous Cysts in the Arachnoid
		4	 Organization of Lymph
		5	 Extravasation of Blood into the Cavity of the Arachnoid
		6	 Chronic and Asymptomatic
		7	 Early Surgical Experience
		8	 Spinal Arachnoid Cysts
		9	 Posterior Fossa Cysts
		10	 Primary Arachnoid Cysts
		11	 Temporal Lobe Agenesis
		12	 Arachnoid Cysts in the Age of Modern Imaging
		13	 Modern Presentation, Management, and Pathogenesis
		14	 Conclusion
		References
	Gender Distribution and Lateralization of Arachnoid Cysts
		1	 Introduction
		2	 Lateralization and Frequency
		3	 Gender Distribution
		4	 Gender Distribution and Lateralization According to Location
			4.1	 Supratentorial ACs
			4.2	 Infratentorial ACs
			4.3	 Spinal ACs
		5	 Conclusion
		References
	Embryology of Arachnoid Mater
		1	 Introduction
		2	 Histology and Location of Meninges Brain Tissue
		3	 Development of the Nervous System
		4	 Emergence of the Meninges
		References
	Histological Findings of Arachnoid Cysts
		1	 Introduction
		2	 Microscopic and Immunohistochemical Features of Arachnoid Cysts
			2.1	 Spectrum of Findings by Light Microscopy
			2.2	 Common Patterns of Immunohistochemical Labeling
		3	 Ultrastructural Features of Arachnoid Cysts
		4	 Pathologic Differentiation of Arachnoid Cyst from Other Cystic CNS Lesions
			4.1	 CNS Infections Presenting as Cysts
			4.2	 Neuroenteric (Enterogenous/Endodermal) Cysts
			4.3	 Colloid Cyst
			4.4	 Rathke’s Cleft Cyst
			4.5	 Epidermoid and Dermoid Cysts
			4.6	 Choroid and Ependymal Cysts
			4.7	 CNS Neoplasms with Cystic Components
			4.8	 Miscellaneous Cystic CNS Lesions
			4.9	 Unusual Clinicoradiographic Presentations of Arachnoid Cysts for which Histological Confirmation Is Prudent
		5	 Conclusion
		References
	Pathophysiology of Arachnoid Cysts
		1	 Introduction
		2	 Clinical and Radiographical Features
		3	 Pathophysiological Mechanisms
			3.1	 Ball Valve Mechanism
			3.2	 Secretory Effect of Arachnoid Lining and Presence of Choroid Plexus in some Cysts
			3.3	 The Osmotic Gradient Between Intracystic and Extracystic Spaces
		4	 Conclusion
		References
	Arachnoid Cysts: Biochemistry
		1	 Introduction
		2	 Pathophysiology
		3	 Biochemistry
			3.1	 Arachnoid Cyst Fluid Composition
			3.2	 Arachnoid Cyst Lining
		4	 Conclusion
		References
Part II: Epidemiology of Arachnoid Cysts
	Editor’s Summary
	Incidence of Arachnoid Cysts
		1	 Introduction
		2	 Incidence of Arachnoid Cysts
		3	 Conclusion
		References
	Genetics of Arachnoid Cysts
		1	 Introduction
		2	 Method
		3	 Pathophysiology of ACs
		4	 Syndromes Associated with ACs
			4.1	 Glutaric Aciduria Type 1 (GA-1)
			4.2	 Aicardi Syndrome
			4.3	 Sturge-Weber Syndrome
			4.4	 Trigeminal Neuralgia
		5	 Other Syndromes Associated with ACs
		6	 Genetics of ACs
		7	 Hydrocephalus
		8	 Conclusion
		References
	Natural History of Arachnoid Cysts
		1	 Introduction
		2	 Natural History
		3	 Growth and Resolution
		4	 Management
		5	 Conclusion
		References
	Anatomic Locations of Arachnoid Cysts
		1	 Introduction
		2	 Intracranial Locations of Arachnoid Cysts
		3	 Intraspinal Locations of Arachnoid Cysts
		4	 Conclusion
		References
	Classification of Arachnoid Cysts
		1	 Introduction
		2	 Classification of Middle Fossa Temporal Cysts
			2.1	 Galassi Classification
		3	 Suprasellar Arachnoid Cyst Classification
		4	 Retroclival Arachnoid Cyst Classification
		5	 Spinal Arachnoid Cysts
		6	 Conclusion
		References
	Intracranial Hemorrhage Associated with Arachnoid Cysts
		1	 Introduction
		2	 Etiology and Classification
		3	 Risk Factors
		4	 Diagnosis and Presentation
		5	 Treatment
		6	 Outcome
		7	 Case Presentation
		8	 Conclusion
		References
	Spontaneous Resolution of Arachnoid Cysts
		1	 Introduction
		2	 Historical Background
		3	 Impact of the Disease
		4	 Radiological Evaluation of Arachnoid Cysts
		5	 Clinical Manifestations of ACs
		6	 Management of AC
		7	 Pathophysiology of Spontaneous Resolution of AC
		8	 Preferential Resolution of AC According to Its Site
		9	 Proposed Mechanism for the Spontaneous Resolution of ACs
		10	 Spontaneous Resolution of a Prepontine AC
		11	 Spontaneous Resolution of a Middle Cranial Fossa AC
			11.1	 Surgical Nuances
		12	 Spontaneous Resolution of an Interhemispheric AC
		13	 Spontaneous Resolution of a Suprasellar AC
		14	 Spontaneous Resolution of a Quadrigeminal AC
		15	 Spontaneous Resolution of Cerebellar AC
		16	 Spontaneous Resolution of a Spinal AC
		17	 Lesions Mimicking an AC, with Varied Presentation
		18	 Conclusion
		References
Part III: Neuroimaging of Arachnoid Cysts
	Editor’s Summary
	Radiological Evaluation of Arachnoid Cysts
		1	 Introduction
		2	 Pathology, Etiology, and Clinical Symptoms
		3	 Radiological Diagnosis of Arachnoid Cysts
			3.1	 Antenatal Ultrasonography
			3.2	 Computed Tomography
			3.3	 Magnetic Resonance Imaging
			3.4	 Cisternography
			3.5	 Fetal Magnetic Resonance Imaging
		4	 Symptoms and Management of ACs
		5	 Intracranial Location of Arachnoid Cysts
			5.1	 Sylvian Fissure/Middle Cranial Fossa
			5.2	 Sellar Region
			5.3	 Interhemispheric Region
			5.4	 Convexity
			5.5	 Quadrigeminal Plate
			5.6	 Intraventricular Region
			5.7	 Infratentorial Region
		6	 Differential Diagnosis
		7	 Conclusion
		References
	Intrauterine Detection of Arachnoid Cysts
		1	 Introduction
		2	 Case Presentation of Prenatal Detection of the Arachnoid Cyst
		3	 Discussion
			3.1	 Prenatal Diagnosis
			3.2	 Natural Course
			3.3	 Size Change
			3.4	 Pregnancy Situation After Prenatal Diagnosis
			3.5	 Associated Anatomical Abnormalities
			3.6	 Neurodevelopment
			3.7	 Fetal Outcome
		4	 Conclusion
		References
	Cisternography of Arachnoid Cysts
		1	 Introduction
			1.1	 Isotope Cisternography
			1.2	 CT Cisternography (CTC)
			1.3	 MR Cisternography (MRC)
				1.3.1	 Non-contrast Material-Enhanced MR Cisternography (NCE-MRC)
				1.3.2	 Contrast Material-Enhanced MR Cisternography (CE-MRC)
			1.4	 Safety of Intrathecal Administration of Gadolinium-Based Contrast Agents
		2	 Conclusion
		References
	SPECT Imaging of Arachnoid Cysts
		1	 Introduction
		2	 Diagnosis of ACs
		3	 SPECT Imaging
		4	 Advantages of SPECT Imaging
		5	 SPECT Imaging for the Detection of ACs
		6	 Challenges That Need to Be Addressed for SPECT Imaging
		7	 Conclusion
		References
Part IV: Clinical Presentations and Differential Diagnosis of Arachnoid Cysts
	Editor’s Summary
	Symptomatology of Craniospinal Arachnoid Cysts
		1	 Introduction
		2	 Intracranial Arachnoid Cysts
		3	 Spinal Arachnoid Cysts
		4	 Conclusion
		References
	Arachnoid Cysts Associated with Hydrocephalus
		1	 Introduction
		2	 Etiological and Pathogenetic Features
		3	 Clinical Signs-Symptoms and Location
		4	 Differential Diagnosis and Natural Evolution
		5	 Surgical Management
		6	 Conclusions
		References
	Epilepsy and Arachnoid Cysts
		1	 Introduction
		2	 Epidemiology
		3	 Pathophysiology
		4	 Electroclinical and Imaging Features
		5	 Diagnostic Workup
		6	 Management of the Association of Arachnoid Cyst with Epilepsy
		7	 Conclusion
		References
	Psychiatric Manifestations of Arachnoid Cysts
		1	 Introduction
		2	 Psychiatric Symptoms or Disorders Related to ACs
		3	 Cognition in ACs
		4	 Physiopathology
		5	 ACs in Patient Populations with Psychiatric Disorders
		6	 Psychiatric Treatments
		7	 Conclusion
		References
	Differential Diagnosis of Intracranial Arachnoid Cysts
		1	 Introduction
		2	 Subdural Hygromas
		3	 Chronic Subdural Hematomas
		4	 Epidermoid and Dermoid Cysts
		5	 Cystic Tumors
			5.1	 Pilocytic Astrocytomas
			5.2	 Hemangioblastomas
			5.3	 Gangliogliomas
			5.4	 Tumors Developed in the Subarachnoid Space
			5.5	 Low-Density Tumors
		6	 Non-neoplastic Cysts
			6.1	 Neurenteric Cysts
			6.2	 Ependymal Cysts
			6.3	 Neuroglial Cysts
		7	 Dandy-Walker Malformations
		8	 Schizencephaly
		9	 Neonatal Hypoxic-Ischemic Encephalopathy
		10	 Encephalomalacia
		11	 Infectious Lesions
			11.1	 Subdural Empyemas
			11.2	 Neurocysticercosis
			11.3	 Hydatid Cysts
		12	 Giant Intracranial Aneurysms
		13	 Intraventricular Cysts
			13.1	 Colloid Cysts
			13.2	 Choroid Fissure Cysts
			13.3	 Choroid Plexus Cysts
			13.4	 Ventricular Diverticula
		14	 Pineal Cysts
		15	 Cystic Suprasellar Lesions
			15.1	 Dilated Third Ventricle
			15.2	 Rathke’s Cleft Cysts
			15.3	 Craniopharyngiomas
		16	 Common Anatomical Variants
			16.1	 Mega Cisterna Magna
			16.2	 Tumefactive Perivascular Spaces
			16.3	 Cavum Septum Pellucidum
		17	 Meningoceles and Pseudomeningoceles
		18	 Conclusion
		References
	Differential Diagnosis of Intraspinal Arachnoid Cysts
		1	 Introduction
		2	 Hydro-Syringomyelia
		3	 Spinal Hygromas
		4	 Spinal Subdural Hematomas
		5	 Cystic Tumors
		6	 Non-Neoplastic Cysts
			6.1	 Epidermoid and Dermoid Cysts
			6.2	 Neurenteric Cysts
			6.3	 Ependymal Cysts
			6.4	 Bronchogenic Cysts
		7	 Ventriculus Terminalis
		8	 Dural Ectasia
		9	 Infectious Lesions
			9.1	 Hydatid Cysts
			9.2	 Suppurations
			9.3	 Cysticercosis
		10	 Meningoceles and Pseudomeningoceles
		11	 Spinal Degenerative Cysts
		12	 Spinal Cord Herniation
		13	 Other Cyst-Like Entities
		14	 Conclusion
		References
Part V: Options in Operative Management of Arachnoid Cysts
	Editor’s Summary
	Aspiration and Drainage of Arachnoid Cysts
		1	 Introduction
		2	 Treatment Options for Arachnoid Cysts
		3	 Cystoperitoneal (CP) Shunting as Primary Treatment
		4	 Needle Aspiration or Burr Hole Drainage for the Arachnoid Cysts
		5	 Conclusion
		References
	Microsurgical Approach to Arachnoid Cysts
		1	 Introduction
			1.1	 Incidence
			1.2	 Natural History
			1.3	 Location
		2	 Presentation
		3	 Indications for Surgical Intervention
		4	 Treatment Options
			4.1	 Conservative Management
			4.2	 Microsurgery
			4.3	 Neuroendoscopy
			4.4	 CSF Diversion
			4.5	 Choice of Treatment Modality
		5	 Conclusion
		References
	Shunt Placement for Arachnoid Cysts
		1	 Introduction
		2	 Diagnosis
		3	 Conservative Treatment
		4	 Surgical Treatment
		5	 Conclusion
		References
	Stereotactic Internal Diversion of Arachnoid Cysts
		1	 Introduction
		2	 Prevalence of Arachnoid Cysts
		3	 Treatments of Intracranial Arachnoid Cysts
		4	 Craniotomy Fenestration to Treat Arachnoid Cysts
		5	 Endoscopic Fenestration for the Treatment of Arachnoid Cysts
		6	 Shunt Placement for the Treatment of Arachnoid Cysts
		7	 Conclusion
		References
	Endoscopic Approach to Arachnoid Cysts
		1	 Introduction
		2	 Pathophysiology
		3	 History of Neuroendoscopy
		4	 Surgical Indications
		5	 Surgical Technique
		6	 Strengths and Limitations of Neuroendoscopy in Arachnoid Cyst
		7	 Conclusion
		References
	Surgical Management of Spinal Arachnoid Cysts
		1	 Introduction
		2	 Patient Selection and Preoperative Evaluation
		3	 Surgical Principles
		4	 Surgical Therapy for Extradural Arachnoid Cysts
		5	 Surgical Therapy for Intradural Extramedullary Arachnoid Cysts
		6	 Surgical Therapy for Intramedullary Arachnoid Cysts
		7	 Surgical Therapy for Tarlov Cysts
		8	 Minimally Invasive Techniques
		9	 Postoperative Complications
		10	 Conclusion
		References
	Postoperative Complications Associated with Arachnoid Cysts
		1	 Introduction
		2	 Treatment Methods for Arachnoid Cysts
		3	 Complications of Arachnoid Cyst Surgery
			3.1	 Anesthetic Consideration
			3.2	 Surgical Complications
		4	 Conclusion
		References
Part VI: Outcome and Prognosis of Arachnoid Cysts
	Editor’s Summary
	Recurrence of Arachnoid Cysts
		1	Introduction
		2	 Natural History of Arachnoid Cysts
		3	 Surgical Treatment of Arachnoid Cysts
		4	 Recurrence of Arachnoid Cysts Following Surgical Intervention
		5	 Conclusion
		References
	Follow-Up of Arachnoid Cysts: Brain Plasticity Following Surgery for Arachnoid Cysts
		1	 Introduction
		2	 Brain Compliance
		3	 How to Measure Cyst Volume
			3.1	 The MacDonald Method
			3.2	 Volumetric Segmentation
			3.3	 Method Comparison
			3.4	 Classification of Post-Operative Radiological Outcomes
		4	 Influence of Surgical Modality on Brain Plasticity
			4.1	 Endoscopic Series
				4.1.1	 Sylvian Fissure Cysts
				4.1.2	 Suprasellar Cysts
			4.2	 Open Series
			4.3	 Cysto-peritoneal Shunt Series
			4.4	 Series Comparing Surgical Modalities
		5	 Correlation of Symptomatology to Cyst Volume Reduction
		6	 Temporal Pattern of Cyst Volume Reduction
		7	 Brain Plasticity in Adults Compared to Children
		8	 Illustrative Cases
			8.1	 Case 1: Sylvian Fissure
			8.2	 Case 2: Convexity AC
			8.3	 Case 3: Suprasellar AC
		9	 Proposed Algorithm for the Follow-Up of Untreated Arachnoid Cysts
		10	 Conclusion
		References
	Future Management of Arachnoid Cysts
		1	 Introduction
		2	 State of the Art
		3	 Future of AC Treatment
			3.1	 Indications: Signaling the Path
			3.2	 Future Improvements in Endoscopic Surgery: Cysto-E(Cho)Volution
			3.3	 Robotic Surgery for AC Treatment: Are We Ready for the (Robo)Revolution?
		4	 Conclusion
		References
	Medicolegal Aspects of Arachnoid Cysts
		1	 Introduction
		2	 Myths and Facts Regarding the Management of an Arachnoid Cyst
			2.1	 Indications for Surgical Treatment
			2.2	 Relationship Between Clinical Symptoms and the Size of the AC
			2.3	 Relationship Between the Location of Headache and the Side of the AC
			2.4	 Resolution of Neurological Symptoms in the Early Postoperative Period
		3	 Case Scenarios of Malpractice due to the Negligent Management of the Arachnoid Cyst
			3.1	 Missed or Delayed Diagnosis and Treatment of an Arachnoid Cyst
			3.2	 Failure in the Diagnosis of Shunt Failure in a Child with Hydrocephalus Caused by an Arachnoid Cyst
			3.3	 Shunt Placement in an Asymptomatic Arachnoid Cyst
			3.4	 Failure in the Management of an Arachnoid Cyst by a Neurologist
			3.5	 Misdiagnosis of a Spinal Arachnoid Cyst as Motor Neurone Disease Causing Delayed Treatment
		4	 Comment Upon Case Scenarios
		5	 Conclusion
		References
Index