Orbital Apex and Periorbital Skull Base Diseases

Foreword
Contents
About the Editors
Part I: Surgical Anatomy
	1: Optic Canal
		1.1	 Introduction
		1.2	 Embryology
		1.3	 Bony Boundaries of Optic Canal
		1.4	 Vasculature
		1.5	 Nerves
		1.6	 Cranial Aperture of the Optic Canal and Morphometry
		1.7	 Physiologic Variants
		1.8	 Translaminar Pressure Difference (TLPD)
		1.9	 Additional Canal Connecting to the Orbit with the Cranial Cavity
		References
	2: Anatomy of the Orbital Apex
		2.1	 Introduction
		2.2	 Surgical Anatomy
			2.2.1	 Skeletal Anatomy of the Orbital Apex
			2.2.2	 Soft Structures of the Orbital Apex
				2.2.2.1	 Optic Canal
				2.2.2.2	 Superior and Inferior Orbital Fissure
		References
	3: Superior Orbital Fissure and Inferior Orbital Fissure
		3.1	 Osteology of the Orbit
		3.2	 Surgical Anatomy of the SOF and the Inferior Orbital Fissure (IOF) in a Frontotemporal Craniotomy
		3.3	 Surgical Anatomy of the SOF and IOF in Endoscopic Endonasal Surgery
		References
	4: Cavernous Sinus and Internal Carotid Artery
		4.1	 Anatomy of the Cavernous Sinus
			4.1.1	 Definition and Formation of the Cavernous Sinus
			4.1.2	 Location and Relationships of the CS
			4.1.3	 Venous Connections and Extensions
			4.1.4	 Venous Compartments of the CS
			4.1.5	 Associated Cranial Nerves
		4.2	 Anatomy of the Internal Carotid Artery
			4.2.1	 Course and Segments of ICA
			4.2.2	 Correlation Between Transcranial and Endonasal Anatomy of the Cavernous ICA
			4.2.3	 Relevant Vascular Anatomic Variations
		4.3	 Relevance of CS Anatomy to the Management of Orbital Lesions
			4.3.1	 Extension of Pathological Process Involving the Orbit
			4.3.2	 Implications for Operative Approaches
				4.3.2.1	 Transcranial Approaches
				4.3.2.2	 Endoscopic Endonasal Approaches
			4.3.3	 Considerations for Potential Complications
		References
	5: Paranasal Sinuses
		5.1	 The Maxillary Sinus
		5.2	 The Anterior and Posterior Ethmoid Sinuses
		5.3	 The Sphenoid Sinus
		5.4	 The Frontal Sinus
		References
Part II: Diagnosis and Radiology
	6: History
		6.1	 Introduction
		6.2	 Chief Complaint
		6.3	 History of Present Illness
			6.3.1	 Onset
			6.3.2	 Duration
			6.3.3	 Site, Radiation, and Character
			6.3.4	 Severity
			6.3.5	 Precipitating, Aggravating, and Relieving Factors
			6.3.6	 Associated Symptoms
			6.3.7	 System Review
		6.4	 Past Medical History
		6.5	 Family History
		6.6	 Drug History
		6.7	 Social History
		6.8	 Conclusions
	7: Physical Examination
		7.1	 Introduction
		7.2	 Inspection
		7.3	 Afferent Visual Pathway
		7.4	 Efferent Visual Pathway
		7.5	 Other Cranial Nerves and Directed Examination
		7.6	 Investigations
		References
	8: Principles of Imaging for Orbital Apex Pathologies
		8.1	 Introduction
		8.2	 Anatomy
		8.3	 Principles of Imaging
		8.4	 Radiological Features of Orbital Apex Pathologies
			8.4.1	 Neoplasms
			8.4.2	 Vascular Anomalies
			8.4.3	 Inflammatory Conditions
			8.4.4	 Infection
			8.4.5	 Extrinsic Compression
		8.5	 Conclusion
		References
Part III: Spectrum of Diseases
	9: Optic Nerve Neoplasm
		9.1	 Introduction
		9.2	 Primary Optic Nerve Tumors
			9.2.1	 Optic Glioma
			9.2.2	 Malignant Optic Glioma
			9.2.3	 Ganglioglioma
			9.2.4	 Medulloepithelioma
			9.2.5	 Hemangioblastoma
			9.2.6	 Oligodendroglioma
		9.3	 Mimickers of Primary Optic Nerve Tumors
			9.3.1	 Germ Cell Tumors
		9.4	 Primary Optic Nerve Sheath Tumors
			9.4.1	 Optic Nerve Sheath Meningioma (ONSM)
			9.4.2	 Optic Nerve Meningeal Hemangiopericytoma
		9.5	 Conclusion
		References
	10: Orbital Apex Vascular Disease
		10.1	 Introduction
		10.2	 Orbital Apex Anatomy
		10.3	 Orbital Apex Syndrome
			10.3.1	 Clinical Features
			10.3.2	 Etiopathogenesis
		10.4	 Orbital Apex Vascular Disease
			10.4.1	 Ophthalmic Arteriovenous Malformations (AVMs)
		10.5	 Arteriovenous Fistulas (AVFs)
		10.6	 Intraorbital Ophthalmic Artery Aneurysm
		10.7	 Hemangiopericytoma of the Orbit
		10.8	 Carotid Cavernous Fistula (CCF)
		10.9	 Cavernous Sinus Thrombosis
		10.10	 Carotid Cavernous Aneurysm
		References
	11: Orbital Apex Infective Diseases
		11.1	 Introduction
		11.2	 Bacterial Infections
		11.3	 Fungal Infections
		11.4	 Viral Infections
		11.5	 Parasitic Infections
		References
	12: Orbital Apex Inflammatory and Infectious Diseases
		12.1	 Bacterial Infections
		12.2	 Fungal Infections
			12.2.1	 Aspergillosis
			12.2.2	 Mucormycosis
				12.2.2.1	 COVID-19-Associated Mucormycosis (CAM)
			12.2.3	 Herpes Zoster Ophthalmicus
		References
	Untitled
	13: Periorbital Skull Base Neoplasms
		13.1	 Introduction
		13.2	 Clinical Presentation and Evaluation
		13.3	 Meningiomas
		13.4	 Schwannomas
		13.5	 Sellar/Suprasellar Tumors
		13.6	 Sinonasal Tumors
		13.7	 Cavernous Angiomas
		13.8	 Lymphangiomas
		13.9	 Lymphomas
		13.10	 Soft Tissue Neoplasms
		13.11	 Solitary Fibrous Tumor
		13.12	 Metastases
		13.13	 Conclusion
		References
	14: Periorbital Bony Diseases
		14.1	 Periorbital Bony Diseases
			14.1.1	 Fibrous Dysplasia
			14.1.2	 Meningiomas
			14.1.3	 Osteomas
			14.1.4	 Dermoid Cysts
		14.2	 Other Rare Tumours
			14.2.1	 Langerhans Cell Histiocytosis
		14.3	 Congenital Abnormalities
			14.3.1	 Craniosynostosis
			14.3.2	 Sclerosing Bone Dysplasias [17, 51]
				14.3.2.1	 Osteopetrosis [17, 52, 53]
				14.3.2.2	 Craniotubular Dysplasias and Hyperostosis
				14.3.2.3	 Caffey-Silverman Syndrome [61–63]
		References
	15: Traumatic Optic Neuropathy
		15.1	 Introduction
		15.2	 Classification
		15.3	 Epidemiology
		15.4	 Clinical Features
			15.4.1	 History
			15.4.2	 Physical Examination
			15.4.3	 Investigation
		15.5	 Management
			15.5.1	 Observation
			15.5.2	 Systemic Corticosteroids
			15.5.3	 Surgical Treatment
		References
Part IV: 360 Degree of Surgical Approaches
	16: Choices of Approaches
		16.1	 Choice of Approaches
			16.1.1	 Background
			16.1.2	 Clock Model Paradigm
			16.1.3	 Paradigm Shift
			16.1.4	 Vision Loss and Intraoperative Optic Nerve Monitoring
		References
	17: Transcranial Approach to Optic Canal and Orbital Apex
		17.1	 Transcranial Approach to Optic Canal and Orbital Apex
			17.1.1	 Introduction
			17.1.2	 Indications
			17.1.3	 Choices of Transcranial Approaches
			17.1.4	 Extradural Approach
				17.1.4.1	 Procedures
				17.1.4.2	 Advantages
				17.1.4.3	 Pearls and Pitfalls
			17.1.5	 Intradural Approach
				17.1.5.1	 Procedures
				17.1.5.2	 Advantages
				17.1.5.3	 Pearls and Pitfalls
			17.1.6	 Hybrid Approach
				17.1.6.1	 Advantages of the Extradural Phase
				17.1.6.2	 Advantages of the Intradural Phase
			17.1.7	 Transcranial Extradural Endoscopic Approach
			17.1.8	 Procedure-Related Complications
		References
	18: Transcranial Approach to Cavernous Sinus and Middle Cranial Fossa
		18.1	 Introduction
		18.2	 Goals of Surgery
		18.3	 Preoperative Neuroradiologic Evaluation
		18.4	 Surgical Procedures
			18.4.1	 Patient Position and Skin Flap Design
			18.4.2	 Anesthetic Considerations
			18.4.3	 Intraoperative Neurophysiologic Monitoring
			18.4.4	 Craniotomy
			18.4.5	 Cerebrospinal Fluid Drainage (CSF) Via External Ventricular Drainage (EVD)
			18.4.6	 Epidural Dissection of the Lateral Wall of the Cavernous Sinus
			18.4.7	 Removal of Anterior Clinoid Process
			18.4.8	 Removal of Petrous Apex
			18.4.9	 Skull Base Triangle
			18.4.10 Dura Opening and Tentorial Cut
			18.4.11 Tumor Resection
			18.4.12 Wound Closure
			18.4.13 Skull Base Carotid Bypass Procedures
		18.5	 Outcomes and Complications
		18.6	 Discussion
		18.7	 Conclusions
		References
	19: Infratemporal Fossa and Orbital Apex
		19.1	 Surgical Anatomy of Orbit
			19.1.1	 Intraconal and Extraconal Structure
			19.1.2	 Arteries
			19.1.3	 Anterior Infratemporal Fossa and Lateral Orbital Wall
			19.1.4	 Symptoms and Syndromes
		19.2	 Disease
		19.3	 Approaches
		19.4	 Clinical Cases
			19.4.1	 Sphenoorbital Meningioma
		19.5	 Schwannoma
		19.6	 Orbital Cavernous Hemangioma
		19.7	 Optic Nerve Sheath Meningioma (ONSM)
		19.8	 Conclusion
		References
	20: Endoscopic Endonasal Approach to Optic Canal and Orbital Apex
		20.1	 Introduction
		20.2	 Pertinent Surgical Anatomy
		20.3	 Surgical Technique
			20.3.1	 Perioperative Preparation
		20.4	 Step-by-Step Surgical Technique
			20.4.1	 Preparation and Anesthesia
			20.4.2	 Uncinectomy and Ethmoidectomy
			20.4.3	 Endoscopic Transethmoidal Approach to Orbital Apex Lesions
			20.4.4	 Optic Canal Decompression: Transethmoidal or Trans-Sphenoidal Approach
		20.5	 Surgical Pearls
		20.6	 Postoperative Management
		20.7	 Complications
		20.8	 Surgical Outcomes: Scientific Evidence
		References
	21: Endoscopic Endonasal Approach to Cavernous Sinus and Middle Cranial Fossa
		21.1	 Introduction
		21.2	 Indications and Advantages
		21.3	 Contraindications
			21.3.1	 Patient’s Characteristics
			21.3.2	 Anatomy
		21.4	 Diagnosis and Preoperative Workup
		21.5	 Surgery
			21.5.1	 Instrumentation and Preparation
		21.6	 EEA to Cavernous Sinus
		21.7	 EEA to Middle Fossa
			21.7.1	 Medial Petrous Apex
			21.7.2	 Middle Fossa
		21.8	 Closure
		21.9	 Conclusions
		References
	22: Endoscopic Endonasal Approach to the Infratemporal Fossa
		22.1	 Introduction
		22.2	 Principles of Approach Selection, Modifications, and Limitations
		22.3	 Surgical Comorbidity
		22.4	 Surgical Setup
		22.5	 Nasal Stage, Access to the Maxillary Sinus, Considerations for Reconstruction (Figs. 22.1 and 22.2)
		22.6	 Pterygopalatine Fossa (Figs. 22.1, 22.2, and 22.3)
		22.7	 Infratemporal Fossa (Figs. 22.1, 22.3, and 22.4)
		References
	23: Endoscopic Transorbital Approach to the Optic Canal and Orbital Apex
		23.1	 Introduction
		23.2	 Surgical Methods
			23.2.1	 Step 1: Skin Incision
			23.2.2	 Step 2: Drilling of Greater Sphenoid Wing
			23.2.3	 Step 3: Extradural Dissection-Peeling of the Cavernous Sinus
		23.3	 Indications
		23.4	 Complications
		23.5	 Surgical Outcomes
		23.6	 Discussion
		23.7	 Conclusion
		References
	24: Endoscopic Transorbital Approach for Orbital Apex Lesions
		24.1	 Introduction
		24.2	 Procedure
			24.2.1	 Patient Position
			24.2.2	 Surgical Technique
		24.3	 Tips for ETOA to the Orbital Apex
		References
	25: Endoscopic Transorbital Approach to Infratemporal Fossa
		25.1	 Introduction
		25.2	 Approach to ITF by ETOA
		25.3	 Comparison of Different Approaches
		25.4	 Case Illustration
		References
	26: Surgical Treatment for Traumatic Optic Neuropathy
		26.1	 Epidemiology
		26.2	 Pathophysiology of TON
		26.3	 Management of TON and Proposed Indication for Surgical Decompression
		26.4	 Surgical Approaches
		26.5	 Basic Setup of ETOCD
		26.6	 Surgical Procedures of ETOCD
		26.7	 Potential Complications of ETOCD
		26.8	 The Future of ETOCD Surgery
		References
Part V: Radiotherapy for Neoplasm
	27: External Radiotherapy for Orbital Apex Lesions: Principles and Practice
		27.1	 Introduction
		27.2	 Radiotherapy
			27.2.1	 Planning
			27.2.2	 Target Volumes [7, 8]
			27.2.3	 Radiotherapy Techniques
			27.2.4	 Three-Dimensional Conformal Radiotherapy (3D-CRT)
			27.2.5	 Intensity-Modulated Radiation Therapy (IMRT) and Volumetric Modulated Arc Radiation Therapy (VMAT)
			27.2.6	 Stereotactic Radiosurgery (SRS) and Fractionated Stereotactic Radiotherapy (FSRT)
			27.2.7	 Side Effects of Radiotherapy
		References
	28: External Photon Radiotherapy for Benign Orbital Apex Lesions
		28.1	 Cavernous Venous Malformation (Hemangioma)
		28.2	 Hemangiopericytoma
		28.3	 Schwannoma
		28.4	 Optic Nerve Sheath Meningioma
			28.4.1	 Case Illustration
		28.5	 Graves Ophthalmopathy
		References
	29: External Photon Radiotherapy for Malignant Orbital Apex Lesions
		29.1	 Lymphoma
		29.2	 Primary Orbital Apex Malignant Tumors
			29.2.1	 Adenoid Cystic Carcinoma
		29.3	 Malignant Lesions Extended from Adjacent Tissue: Nasopharyngeal Carcinoma
		29.4	 Orbital Apex Metastases
		References
	30: Proton Therapy for Malignant Orbital Apex Lesions
		30.1	 Introduction to Proton Beam
		30.2	 Dosimetric Comparison Between Proton and Photon Radiotherapy for Malignant Orbital Apex Lesions
		30.3	 Clinical Studies of Proton Therapy for Neoplasms in Orbital Apex
		30.4	 Orbital Rhabdomyosarcoma
			30.4.1	 Background
			30.4.2	 Radiotherapy Target Volumes and Dose Fractionation
			30.4.3	 Clinical Study of Proton Therapy in Orbital Rhabdomyosarcoma
		30.5	 Optic Pathway Gliomas
			30.5.1	 Background
			30.5.2	 Radiotherapy Target Volumes and Dose Fractionation
			30.5.3	 Clinical Studies of Proton Therapy in Optic Pathway Gliomas
		30.6	 Adenoid Cystic Carcinoma of the Lacrimal Gland
			30.6.1	 Background
			30.6.2	 Radiotherapy Target Volumes and Dose Fractionation
			30.6.3	 Clinical Studies on Proton Therapy for Lacrimal Gland Adenoid Cystic Carcinoma
		30.7	 Summary
		References