The Sutures of the Skull: Anatomy, Embryology, Imaging, and Surgery

Description

This book provides an in-depth review of the sutures of the skull. The premature closure of the sutures of the skull (craniosynostosis) due to genetic or metabolic etiologies results in typical progressive skull deformity, due to both the inhibition of growth caused by the affected cranial suture and associated compensatory expansion of the skull along the open ones. Today, it is well known that early diagnosis of craniosynostosis is crucial for the best surgical outcomes and for the normal development of the brain and cosmetic appearance of the skull. As such, in addition to the anatomy, biology, genetics and embryology of the sutures of the skull, the book also covers the diagnosis and treatment of different forms of craniosynostosis such as metopism, and animal models for cranial suture research. This comprehensive work is a valuable resource for neuroscientists at all levels, from graduate students to researchers, as well as neurosurgeons, neuroanatomists, pediatricians, and neurologists seeking both basic and more advanced information on the unique structure of the sutures of the human skull. Contents Chapter 1: Introduction 1.1 Introduction References Chapter 2: The Sutures of the Skull: A Historical Perspective 2.1 Introduction 2.2 Homer and Mythological Era 2.3 Hellenic Hippocrates Era 2.4 Other Ancient Hellenic Studies 2.5 American-African and Mediorient Ancient Studies 2.6 Arabic World 2.7 Medieval Times 2.8 Nineteenth Century 2.9 Modern Era 2.10 Conclusion References Chapter 3: Embryological and Histological Features of the Cranial Sutures 3.1 Introduction 3.1.1 An overview of the Embryonic Development of the Skeletal System and Skull 3.1.2 An Overview of Ossification in the Skull Bones 3.2 Development of Sutures 3.3 Individual Bone Development and Ossification in Relation to Sutures 3.3.1 Ossification Centers in Neurocranial Bones 3.3.1.1 Frontal Bone 3.3.1.2 Parietal Bone 3.3.1.3 Occipital Bone 3.3.1.4 Temporal Bone 3.3.1.5 Sphenoid Bone 3.3.1.6 Ethmoid Bone 3.3.1.7 Additional Ossification Center and Sutural (Wormian) Bones 3.3.2 Ossification Centers of the Viscerocranial Bones 3.3.2.1 Maxilla 3.3.2.2 Palatine Bone 3.3.2.3 Os Zygomaticum 3.3.2.4 Vomer 3.3.2.5 The Other Viscerocranial Bones 3.3.2.6 Histology of Cranial Sutures and Fontanelles Histology of Sutures Histology of Fontanelles 3.4 Molecular Mechanisms and Clinical Reflections in Sutural Development 3.4.1 Nonsyndromic Craniosynostosis 3.4.1.1 Sagittal Synostosis 3.4.1.2 Coronal Synostosis 3.4.1.3 Metopic Synostosis 3.4.1.4 Lambdoid Synostosis 3.4.2 Syndromic Craniosynostosis 3.5 Gene Mutations Associated with Craniosynostoses 3.5.1 FGFR1, FGFR2 and FGFR3 Mutations 3.5.2 Transforming Growth Factor β (TGF β) Mutations 3.5.3 Mutations of Transcription Factors 3.5.4 TWIST1 (twist-related protein 1) Mutations References Chapter 4: Anatomy of the Sutures of the Calvaria 4.1 Introduction 4.2 Sutures of the Calvaria 4.2.1 Metopic Suture (Frontal) 4.2.2 Coronal Suture 4.2.3 Lambdoid Suture 4.2.4 Sagittal Suture 4.2.5 Squamous Suture 4.2.6 Accessory Parietal Suture 4.2.7 Wormian Bone 4.3 Clinical Relevance 4.3.1 Fracture Versus Suture References Chapter 5: Anatomy of the Sutures of the Skull Base 5.1 Introduction 5.2 Sutures of the Cranial Base 5.2.1 Occipitomastoid Suture 5.2.2 Parietomastoid Suture 5.2.3 Mendosal Suture 5.2.4 Sphenofrontal Suture 5.2.5 Sphenosquamous Suture 5.2.6 Sphenoethmoidal Suture 5.2.7 Sphenoparietal Suture 5.2.8 Petrosquamous Suture 5.2.9 Sphenopetrosal Suture 5.2.10 Sphenooccipital Suture 5.2.11 Frontoethmoid Suture 5.3 Clinical Relevance 5.3.1 Craniosynostosis 5.3.2 Basal Cranial Fractures References Chapter 6: Anatomy of the Sutures of the Face 6.1 Introduction 6.2 Sutures of the Face 6.2.1 Frontonasal Suture 6.2.2 Frontoethmoidal Suture 6.3 Frontolacrimal Suture 6.3.1 Frontomaxillary Suture 6.3.2 Frontozygomatic Suture 6.3.3 Zygomaticomaxillary (infraorbital) Suture (Facial, Orbital, and Infratemporal Parts) 6.3.4 Ethmoidomaxillary Suture 6.3.5 Nasomaxillary Suture 6.3.6 Internasal Suture 6.3.7 Sphenozygomatic Suture 6.3.8 Lacrimomaxillary Suture 6.3.9 Ethmoidolacrimal Suture 6.3.10 Intermaxillary Suture (Facial Part) 6.3.11 Temporozygomatic Suture 6.3.12 Palatomaxillary Suture (Nasal Part) 6.3.13 Lacrimoconchal Suture 6.3.14 Palatoethmoidal Suture 6.3.15 Sphenovomerine Suture 6.3.16 Sphenomaxillary Suture (Pterygomaxillary Suture) 6.3.17 Sphenoethmoidal Suture 6.3.18 Incisive Suture 6.3.19 Median Palatine Suture 6.3.20 Transverse Palatine Suture 6.4 Clinical Relevance 6.4.1 Cleft Palate 6.4.2 Fractures Related to Sutures of the Face 6.4.2.1 Le Fort I Fracture 6.4.2.2 Le Fort II Fracture 6.4.2.3 Le Fort III Fracture 6.4.2.4 Naso-orbitoethmoid Fracture (NOE Fracture) 6.4.2.5 Zygomaticomaxillary Complex Fracture (ZMC Fracture) 6.4.2.6 Orbital Fractures 6.4.3 Rapid Maxillary Expansion References Chapter 7: Normal Growth of the Sutures of the Skull 7.1 Suture and Synchondroses of the Skull: Identification 7.2 Sutures and Synchondroses Are Cranial Growth Centers: Formation and Development 7.2.1 Skull Development: Role of Sutures and Synchondroses 7.2.2 Histology 7.2.3 Stages of Sutural Growth and Closure 7.2.4 Synchondroses Growth and Closure 7.3 Assessment of Sutures and Synchondroses Growth: Role of CT and MRI 7.3.1 CT and MRI: What Is the Best Technique? 7.3.2 CT and MRI: Sensitivity and Specificity 7.3.3 Assessment of Sutures Growth on CT 7.3.4 Assessment of Sutures Growth in MRI 7.4 Plastic Changes of Sutural Area During Closure and Fusion Processes 7.4.1 Grading System of Closure 7.4.2 Degree of Interdigitation: Sutural Patterns 7.5 Sutures Fusion: Process and Timing References Chapter 8: Variations in Sutural Anatomy of the Skull 8.1 Metopic Suture Variations 8.2 Epipteric Bone 8.3 Coronal Suture 8.4 Interparietal Bone 8.5 Sagittal Suture Variations 8.6 Variation in the Sutures of the Temporal Bone 8.7 Lambdoid Suture Variations 8.7.1 Os Incae 8.8 Mendosal Suture 8.9 Os Japonicum 8.10 Infraorbital Suture 8.11 Transverse Palatine Suture 8.12 Miscellaneous Sutural Variations 8.13 Conclusion References Chapter 9: Metopism: Anatomical, Clinical and Surgical Aspects 9.1 Introduction and Terminology 9.2 Epidemiology 9.3 Etiology 9.3.1 Anatomical Aspects 9.4 Relationship Between Metopism and the Frontal Sinus 9.4.1 Clinical Aspects 9.4.2 Surgical Aspects: Metopic Synostosis—Trigonocephaly References Chapter 10: Skull Sutures as Anatomical Landmarks 10.1 Skull Sutures 10.2 Calvarial Sutures 10.2.1 Coronal Suture 10.2.2 Sagittal Suture 10.2.3 Lambdoid Suture 10.2.4 Squamosal Suture 10.2.5 Occipitomastoid Suture 10.2.6 Parietomastoid Suture 10.2.7 Frontal Suture 10.3 Facial Sutures (Fig. 10.9) 10.3.1 Frontozygomatic Suture 10.3.2 Frontomaxillary Suture 10.3.3 Frontonasal Suture 10.3.4 Temporozygomatic Suture 10.3.5 Zygomaticomaxillary Suture 10.3.6 Nasomaxillary Suture 10.3.7 Sphenofrontal Suture 10.3.8 Sphenozygomatic Suture 10.4 Skull Point Landmarks 10.4.1 Bregma 10.4.2 Lambda 10.4.3 Pterion 10.4.4 Asterion 10.4.5 Inion 10.4.6 External Occipital Protuberance 10.4.7 Basion and Opisthion 10.4.8 Obelion References Chapter 11: A Brief Introduction to the Biomechanics of Craniofacial Sutures 11.1 Introduction 11.2 Inherent Mechanical Properties of the Sutures 11.3 Role and Function of the Sutures 11.4 Response of Sutures to Mechanical Loads 11.5 Discussion References Chapter 12: Radiological Evaluation of the Sutures of the Skull 12.1 Introduction 12.1.1 Development of the Sutures 12.1.2 Gross Anatomy: Sectioned Images 12.2 Imaging Modalities 12.2.1 Radiography 12.2.2 Computed Tomography 12.2.3 Magnetic Resonance Imaging 12.2.4 Ultrasound 12.3 Differential Diagnosis: Sutures and Fractures in Radiological Images 12.3.1 Radiography 12.3.2 Computed Tomography References Chapter 13: The Biology of the Sutures of the Skull 13.1 Introduction 13.2 Components of the Cranial Suture 13.3 Properties of the Cranial Suture, Compared to Bone 13.4 Unique Skeletal Stem Cell Populations are Responsible for Maintenance and Repair 13.5 Cranial Suture Mesenchymal Stem Cellsare Responsible for Craniofacial Bone Growth and Repair 13.6 Cellular Processes Involved in Suture Morphogenesis 13.6.1 Cell Death in the Suture Mesenchyme Leads to Cranial Suture Fusion 13.6.2 Aberrant Cell Fate Specification of the Suture Mesenchyme Leads to Cranial Suture Fusion 13.7 Interactions Between Neighboring Tissues 13.8 Comparison of Cranial Sutures to Facial Sutures 13.9 Conclusions and Perspectives References Chapter 14: Types of Craniosynostosis and their Etiology, Pathophysiology and Epidemiology 14.1 History 14.2 Cranial and Facial Embryogenesis 14.3 Epidemiology and Incidence 14.4 Etiology 14.4.1 Genetic Factors 14.4.2 Metabolic Factors 14.4.3 Epidemiological Factors 14.4.4 Pathophysiology 14.4.5 Impact over Cranial Cavity 14.4.6 Ophthalmic Dysfunctions 14.4.7 Impact over Intellectual Functions 14.4.8 Epidemiological Characteristics 14.4.9 Scaphocephaly 14.4.9.1 Coronal Plagiocephaly or Unilateral Coronal Craniosynostosis 14.4.9.2 Deformational Posterior Plagiocephaly 14.4.9.3 Posterior Plagiocephaly (lamboid) 14.4.9.4 Trigonocephaly 14.4.9.5 Brachycephaly or Bilateral Coronal Craniosynostosis 14.4.9.6 Oxycephaly 14.4.9.7 Syndromatic Craniosynostosis Crouzon Syndrome Clinical and imaging characteristics 14.4.9.8 Apert Syndrome 14.4.9.9 Saethre-Chotzen Syndrome Clinical and Imaging Characteristics 14.4.9.10 Pfeiffer Syndrome Clinical and Imaging Characteristics 14.4.9.11 Cloverleaf Skull 14.5 Treatment 14.5.1 Surgical Treatment 14.5.1.1 Classic Surgical Treatment 14.5.1.2 Technical Details 14.5.1.3 Scaphocephaly. Surgical treatment 14.5.1.4 Brachycephaly. Surgical Treatment 14.5.1.5 Trigonocephaly Surgical Treatment 14.5.1.6 Plagiocephaly. Surgical Treatment 14.5.2 Syndromic Craniosynostosis: Crouzon and Apert Syndromes. Surgical Treatment 14.5.2.1 Endoscopic Surgery 14.5.2.2 Helmets as an Adjacent Treatment References Chapter 15: Genetic Features of Craniosynostosis 15.1 Introduction 15.2 Development and Growth of the Normal Cranial Vault 15.3 Signaling Mechanisms Underlying the Pathophysiology of Craniosynostosis 15.4 Genetics of Craniosynostosis 15.4.1 Genetics of Syndromic Craniosynostosis 15.4.2 Genetics of Non-Syndromic Craniosynostosis 15.5 Genetic Counselling 15.6 Conclusion References Chapter 16: Imaging Modalities for Craniosynostosis 16.1 Introduction 16.2 Radiological Approach 16.2.1 Preoperative Evaluation 16.2.1.1 Confirmation of the Diagnosis 16.2.1.2 Detection of Concomitant Anomalies 16.2.1.3 Treatment Planning 16.2.1.4 Prognosis Estimation 16.2.2 Postoperative Evaluation 16.3 Radiological Imaging Modalities 16.3.1 Plain X-rays 16.3.2 Computed Tomography 16.3.3 Ultrasonography 16.3.4 Magnetic Resonance Imaging 16.3.5 Digital Angiography 16.4 Conclusion References Chapter 17: Syndromic Craniosynostosis 17.1 Introduction 17.2 Clinical Features 17.2.1 Apert Syndrome 17.2.2 Crouzon Syndrome 17.2.3 Pfeiffer Syndrome 17.2.4 Antley-Bixler Syndrome 17.2.5 Muenke Syndrome 17.2.6 Saethre–Chotzen Syndrome 17.2.7 Cranio-Frontonasal Syndrome 17.3 Radiology 17.3.1 Plain Roentgenogram 17.3.2 Multidetector Computed Tomography (MDCT) with Three-dimensional (3D) Volume Rendering 17.4 MRI 17.4.1 Follow-up Imaging 17.5 Management 17.5.1 Posterior Expansion 17.5.1.1 Indication and Timing 17.5.1.2 Procedure 17.5.2 Anterior Advancement 17.5.3 Fronto-orbital Advancement 17.5.3.1 Indication and Timing 17.5.3.2 Procedure 17.5.4 Fronto-facial Advancement 17.5.5 Complementary Procedures 17.5.5.1 Barrel Staving 17.5.5.2 Suturectomy 17.5.5.3 Free Floating Bones 17.5.6 Teamwork 17.5.7 Complications 17.5.8 Tips and Rules References Chapter 18: Surgery for Craniosynostosis 18.1 Introduction 18.2 Indications for Surgery 18.3 General Surgical Considerations 18.4 Surgery for Nonsyndromic Craniosynotosis 18.4.1 Metopic Synostosis (Trigonocephaly as Phenotypic Presentation) 18.4.1.1 Diagnosis, and Indications for and Timing of Operative Treatment 18.4.1.2 Preoperative Planing, Surgical Objectives and Special Equipment 18.4.1.3 Anesthetic Considerations 18.4.1.4 Operative Procedure Positioning Sterile Scrub, Draping and Local Anesthetic Skin Incision Initial Deconstructive Phase Subsequent Reconstructive Phase Closure Specific Instrumentation 18.4.1.5 Postoerative Management 18.4.1.6 Complications 18.4.1.7 Outcome, Prognosis and Follow-up 18.4.2 Unilateral and Bilateral Coronal Synostosis (Anterior or Frontal Unilateral and Bilateral Plagiocephaly, as Phenotypic Presentation) 18.4.2.1 Unilateral Coronal Synosthosis (Anterior or Frontal Unilateral Plagiocephaly, as Phenotypic Presentation) Diagnosis, Indications, and Timing for Operative Treatment Preoperative Planning, Surgical Objectives and Special Equipment Anesthetic Considerations Operative Procedure Positioning Sterile Scrub, Draping and Local Anesthetic Skin Incision Initial Deconstructive Phase Subsequent Reconstructive Phase Closure Specific Instrumentation 18.4.2.2 Postoperative Management 18.4.2.3 Complications Outcome, Prognosis and Follow-up 18.4.2.4 Bilateral Coronal Synostosis (Brachycephaly as Phenotypic Presentation) General Considerationds (Diagnosis, Surgery) Distraction Osteogenesis in Bicoronal Synostosis Closure Specific Instrumentation Postoperative Management Complications Outcome, Prognosis and Follow-up 18.4.3 Sagittal Synostosis (Dolichocephaly, Scaphocephaly as Phenotypic Presentation) 18.4.3.1 Diagnosis, Indications and Timing for Operative Treatment 18.4.3.2 Preoperative Planning, Surgical Objectives and Special Equipment 18.4.3.3 Anesthetic Considerations 18.4.3.4 Operative Procedure Positioning Sterile Scrub, Draping and Local Anesthetic Skin Incision Initial Deconstructive Phase Closure Specific Instrumentation 18.4.3.5 Postoperative Management 18.4.3.6 Complications 18.4.3.7 Outcome, Prognosis and Follow-up 18.4.3.8 Lambdoid Synostosis (Posterior Plagiocephaly as Phenotypic Presentation) 18.4.3.9 Diagnosis, Indications for Operative Treatment and Timing 18.4.3.10 Preoperative Planning, Surgical Objectives and Special Equipment 18.4.3.11 Anesthetic Considerations 18.4.3.12 Operative Procedure Positioning Sterile Scrub, Draping and Local Anesthetic Skin Incision Initial Deconstructive Phase Additional Reconstructive Phase Closure Specific Instrumentation 18.4.3.13 Postoperative Management 18.4.3.14 Complications 18.4.3.15 Outcome, Prognosis and Follow-up 18.5 Surgery for Syndromic Craniosynosthosis 18.5.1 Craniofacial Syndromes 18.5.1.1 Crouzon Syndrome (Acrocephalosyndactyly Type II) 18.5.2 Saethre-Chotzen Syndrome (acrocephalosyndactyly type III) 18.5.3 Carpenter Syndrome 18.5.4 Muenke Syndrome 18.5.5 Cloverleaf Skull (Kleeblattschädel) Deformity 18.5.6 Surgical Approaches and Treatments for Craniosynostosis 18.5.6.1 Bilateral Coronal Synostosis 18.5.7 Children Younger than 1 Year 18.5.8 Children Older than 3 Years 18.5.9 Children Between 1 and 3 Years of Age 18.5.9.1 Posterior Vault Distraction 18.5.9.2 Spring-assisted Cranioplasty 18.5.9.3 Fronto-orbital Advancement 18.5.10 Surgical Approaches and Treatments for Midface Hypoplasia 18.5.10.1 Le Fort III Osteotomy 18.5.10.2 Monobloc Advancement 18.5.10.3 Distraction Osteogenesis of the Midface 18.5.11 Surgical Approaches and Treatments for Hypertelorism 18.5.11.1 Box Orbitotomy and Medial Orbit Translocation 18.5.11.2 Facial Bipartition 18.5.12 Complications in Surgery for Syndromic Craniosynostosis 18.6 Conclusion References Chapter 19: Experimental Animal Models in Cranial Suture Biology: Molecular and Pharmacological Treatment Strategies 19.1 Introduction 19.2 FGF/FGFR Signaling 19.3 TGFβ/BMP Signaling 19.4 Future Directions 19.5 Summary References Index