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Current Pediatric Reviews 2020To review and present the current knowledge of incidence, signs and symptoms, diagnosis and treatment of the occipital encephalocele. (Review)
Review
AIMS
To review and present the current knowledge of incidence, signs and symptoms, diagnosis and treatment of the occipital encephalocele.
BACKGROUND
Encephalocele (E) is a defect of the neural tube that refers to congenital malformations featured by skull defect and dura with extracranial spread of intracranial structures. Occipital encephalocele (OE) are the most common form of this congenital disorder and are manifested as a swelling of different sizes over the occipital bone in the midline. Proper diagnosis and treatment is highly important in the management of this congenital malformation of brain.
OBJECTIVE
To review and present the current knowledge of incidence, signs and symptoms, diagnosis and treatment of the occipital encephalocele.
METHODS
We conducted a search of case reports or case-series of patients by the use of electronic databases: Pub Med, Medline, Index Medicus, Scorpus. The key words were: encephalocele, occipital encephalocele, neural tube defect, congenital malformation. The search was updated to December 31, 2018. Papers published in English were the only source of information.
RESULTS
Occipital encephalocelle are more frequent in females than in males. The incidence is between 1 in 3000 to 1 in 10,000 live births; approximately 90% of them involve the midline. Magnetic resonance imaging is the method of choice in diagnosis and surgery is the best option for the treatment of OE. Overall morbidity and mortality is still high in spite of advenced surgical management, but have been significantly improved in recent years thanks to sophisticated highresolution imaging, adequate and proper surgical treatment and decent post-operative care.
CONCLUSION
Occipital encephalocele is the most common form of encephalocele. The diagnosis is mostly based by the use of neuroimaging techniques. Operation is the best option for treatment. Overall morbidity and mortality is still high, but have been significantly improved in recent years thanks to sophisticated high-resolution imaging, adequate and proper surgical treatment and decent post-operative care.
Topics: Encephalocele; Humans; Incidence; Neuroimaging; Neurosurgical Procedures; Occipital Bone; Prognosis
PubMed: 31656152
DOI: 10.2174/1573396315666191018161535 -
The Orthopedic Clinics of North America Oct 2021Craniocervical injuries (CCJs) account for 10% to 30% of all cervical spine trauma. An increasing number of patients are surviving these injuries due to advancements in... (Review)
Review
Craniocervical injuries (CCJs) account for 10% to 30% of all cervical spine trauma. An increasing number of patients are surviving these injuries due to advancements in automobile technology, resuscitation techniques, and diagnostic modalities. The leading injury mechanisms are motor vehicle crashes, falls from height, and sports-related events. Current treatment with urgent rigid posterior fixation of the occiput to the cervical spine has resulted in a substantial reduction in management delays expedites treatment of CCJ injuries. Within CCJ injuries, there is a spectrum of instability, ranging from isolated nondisplaced occipital condyle fractures treated nonoperatively to highly unstable injuries with severely distracted craniocervical dissociation. Despite the evolution of understanding and improvement in the management of cases regarding catastrophic failure to diagnose, subsequent neurologic deterioration still occurs even in experienced trauma centers. The purpose of this article is to review the injuries that occur at the CCJ with the accompanying anatomy, presentation, imaging, classification, management, and outcomes.
Topics: Atlanto-Axial Joint; Atlanto-Occipital Joint; Axis, Cervical Vertebra; Cervical Atlas; Cervical Vertebrae; Humans; Joint Dislocations; Occipital Bone; Spinal Fractures; Spinal Injuries; Trauma, Nervous System
PubMed: 34538354
DOI: 10.1016/j.ocl.2021.05.013 -
Acta Neurochirurgica. Supplement 2019Occipitocervical fusion (OCF) is indicated for instability at the craniocervical junction (CCJ). Numerous surgical techniques, which evolved over 90 years, as well as... (Review)
Review
Occipitocervical fusion (OCF) is indicated for instability at the craniocervical junction (CCJ). Numerous surgical techniques, which evolved over 90 years, as well as unique anatomic and kinematic relationships of this region present a challenge to the neurosurgeon. The current standard involves internal rigid fixation by polyaxial screws in cervical spine, contoured rods and occipital plate. Such approach precludes the need of postoperative external stabilization, lesser number of involved spinal segments, and provides 95-100% fusion rates. New surgical techniques such as occipital condyle screw or transarticular occipito-condylar screws address limitations of occipital fixation such as variable lateral occipital bone thickness and dural sinus anatomy. As the C0-C1-C2 complex is the most mobile portion of the cervical spine (40% of flexion-extension, 60% of rotation and 10% of lateral bending) stabilization leads to substantial reduction of neck movements. Preoperative assessment of vertebral artery anatomical variations and feasibility of screw insertion as well as visualization with intraoperative fluoroscopy are necessary. Placement of structural and supplemental bone graft around the decorticated bony elements is an essential step of every OCF procedure as the ultimate goal of stabilization with implants is to provide immobilization until bony fusion can develop.
Topics: Bone Transplantation; Cervical Vertebrae; Fracture Fixation, Internal; Humans; Joint Instability; Occipital Bone; Spinal Fusion
PubMed: 30610329
DOI: 10.1007/978-3-319-62515-7_35 -
The Canadian Journal of Neurological... Mar 2020A 73-year-old male with a history of chronic ataxia presented with transient facial droop to the Emergency Department. A CT angiogram and MRI with diffusion weighted...
A 73-year-old male with a history of chronic ataxia presented with transient facial droop to the Emergency Department. A CT angiogram and MRI with diffusion weighted imaging (DWI) were negative for stroke. However, incidental note was made of numerous giant arachnoid granulation pits in the posterior fossa predominantly involving the left occipital bone (Figure 1). These arachnoid pits demonstrated multiple foci of herniation of the adjacent cerebellar parenchyma into the pits with gliosis of the herniated parenchyma and focal encephalomalacia of the subjacent cerebellar parenchyma. Review of bone windows on a remote CT brain performed almost 13 years earlier confirmed this to be a longstanding abnormality (Figure 2). The patient's physical exam was suggestive of cerebellar ataxia with left-sided dysmetria on finger to nose testing and a wide-based unsteady gait.
Topics: Aged; Cerebellar Ataxia; Cerebral Angiography; Computed Tomography Angiography; Diffusion Magnetic Resonance Imaging; Encephalocele; Encephalomalacia; Humans; Male; Occipital Bone; Osteolysis
PubMed: 31648659
DOI: 10.1017/cjn.2019.318 -
Acta Neurochirurgica. Supplement 2019Occipitocervical fusion is a surgical technique in continuous evolution due to the innovation of devices, operative and instrumentation techniques. The aetiologies...
Occipitocervical fusion is a surgical technique in continuous evolution due to the innovation of devices, operative and instrumentation techniques. The aetiologies responsible for occipitocervical instability are trauma, neoplastic disease, metabolic disease or congenital disease. A variety of stabilization techniques are currently available depending on the type of patient and surgeon's experience. Each of these techniques requires thorough knowledge of the anatomy of the craniovertebral junction.
Topics: Cervical Vertebrae; Humans; Joint Instability; Occipital Bone; Spinal Fusion
PubMed: 30610328
DOI: 10.1007/978-3-319-62515-7_34 -
Clinical Anatomy (New York, N.Y.) May 2022In forensic work, the spheno-occipital synchondrosis helps identify the deceased as a child or young adult. In the past, it was generally held that the synchondrosis... (Review)
Review
In forensic work, the spheno-occipital synchondrosis helps identify the deceased as a child or young adult. In the past, it was generally held that the synchondrosis closed between the late teens and 25 years, but recent studies have suggested closure in adolescence. There are also suggestions that the age at closure recorded might be influenced by ancestry and the technique used to study the joint. This comprehensive review of the literature of the past 60 years concludes that the age of closure of the spheno-occipital synchondrosis is very variable, from childhood to the mid-twenties, with no obvious association with the geographical location of the study population. We note that some studies on bony specimens indicated later closure than others using clinical images and draw attention to a possible misinterpretation of the so-called "fusion scar" which might explain this incongruity. Despite an increasing acceptance that the synchondrosis usually closes in adolescence, we are concerned that insufficient heed is being paid to reports of closure in childhood and in the early to mid-twenties. We conclude that, for forensic purposes, it is unwise to declare that the synchondrosis closes in adolescence. It would be safer to state that a closed synchondrosis indicates a person 6 years or over and that an open synchondrosis may be seen up to the mid-twenties. Clearly, for younger individuals, the dentition and, for all individuals in this age range, documentation of unfused postcranial epiphyses would be important in attempting to narrow this very broad estimation of age.
Topics: Adolescent; Age Determination by Skeleton; Child; Epiphyses; Humans; Occipital Bone; Sphenoid Bone; Young Adult
PubMed: 35141949
DOI: 10.1002/ca.23847 -
Child's Nervous System : ChNS :... Dec 2015The formation of the occipital bone is intricate and has been extensively studied with many controversial conclusions, but with minimal effort being focused on the genes... (Review)
Review
INTRODUCTION
The formation of the occipital bone is intricate and has been extensively studied with many controversial conclusions, but with minimal effort being focused on the genes and molecular interactions necessary for its formation. A better understanding of this bone of the calvarial and skull base may shed light on pathologies where the occiput is often considered the offending entity.
METHODS
A review of the germane medical literature using textbooks and standard search engines was performed to gather information about previous conclusions as it pertains to the embryology and ossification of the occipital bone.
RESULTS
The occipital bone has both membranous and cartilaginous origin with ossification occurring as early as week 9 of fetal gestation. Its formations is dependent on complex interacts between genes and molecules with pathologies resulting from disruption of this delicate process.
CONCLUSION
There has been much controversy in the past in regards to the development and ossification process necessary for occipital bone formation, which has only recently been clarified with documentation of the genes and molecular interactions necessary for its formation. Lastly, this improved knowledge might improve our understanding of such congenital derailments as the Chiari malformations.
Topics: Humans; Occipital Bone; Osteogenesis; Skull Base
PubMed: 26280629
DOI: 10.1007/s00381-015-2870-8 -
American Journal of Human Biology : the... Oct 2022We explore the contribution of biological sex and biomechanical activity from subsistence to occipital bone variation. Previous studies have used occipital bone traits...
We explore the contribution of biological sex and biomechanical activity from subsistence to occipital bone variation. Previous studies have used occipital bone traits to determine biological sex and identify ancestry to differing degrees of success. Biomechanical stress from variation in subsistence and gender-based divisions of labor could perhaps explain some of the noise in the signal for these grouping variables. To explore this possibility, we used metric (foramen magnum length and breadth, external occipital protuberance depth, lambda-inion length, bicondylar breadth) and nonmetric traits (general occipital form, presence of a nuchal crest, and nuchal line count). We collected original data and mined published data for our analysis using skeletal collections of Native American hunter-gatherers and horticulturalists, a historic military site, and contemporary study collections. We find that the foramen magnum area exhibits sexual dimorphism and is not influenced by subsistence, but the accuracy of sex estimation is only 71%, suggesting the chance of being correct at slightly more than two-thirds. All traits exhibited sex-based variation but only bicondylar breadth and lambda-inion metrics exhibited subsistence-based variation. Given the limited amount of variance explained by either sex or sex and subsistence, biomechanics may still play a role but not from the influence of subsistence practices in these datasets. Additional data from a wider array of skeletal samples, perhaps with known occupation, is warranted if we are to understand how occipital variation is shaped.
Topics: Biomechanical Phenomena; Foramen Magnum; Humans; Occipital Bone; Phenotype; Sex Characteristics
PubMed: 36193635
DOI: 10.1002/ajhb.23792 -
Operative Neurosurgery (Hagerstown, Md.) Apr 2021Obtaining successful arthrodesis at the craniocervical junction and atlantoaxial joint can be more challenging than in other segments of the cervical spine. This... (Review)
Review
BACKGROUND
Obtaining successful arthrodesis at the craniocervical junction and atlantoaxial joint can be more challenging than in other segments of the cervical spine. This challenge stems from the relatively hypermobile joints between the occipital condyles, the motion that occurs at C1 and C2, as well as the paucity of dorsal bony surfaces for posterior arthrodesis. While multiple different techniques for spinal fixation in this region have been well described, there has been little investigation into auxiliary methods to improve fusion rates.
OBJECTIVE
To describe the use of an occipital bone graft to augment bony arthrodesis in the supraaxial cervical spine using a multidisciplinary approach.
METHODS
We review the technique for harvesting and placing a vascularized occipital bone graft in 2 patients undergoing revision surgery at the craniocervical junction.
RESULTS
The differentiation from nonvascularized bone graft, either allograft or autograft, to a bone graft using vascularized tissue is a key principle of this technique. It has been well established that vascularized bone heals and fuses in the spine better than structural autogenous grafts. However, the morbidity and added operative time of harvesting a vascularized flap, such as from the fibula or rib, precludes its utility in most degenerative spine surgeries.
CONCLUSION
By adapting the standard neurosurgical procedure for a suboccipital craniectomy and utilizing the tenets of flap-based reconstructive surgery to maintain the periosteal and muscular blood supply, we describe the feasibility of using a vascularized and pedicled occipital bone graft to augment instrumented upper cervical spinal fusion. The use of this vascularized bone graft may increase fusion rates in complex spine surgeries.
Topics: Atlanto-Axial Joint; Bone Transplantation; Cervical Vertebrae; Humans; Occipital Bone; Spinal Fusion
PubMed: 33609121
DOI: 10.1093/ons/opab036 -
Journal of Neurosurgery. Pediatrics Jul 2024Congenital anomalies of the atlanto-occipital articulation may be present in patients with Chiari malformation type I (CM-I). However, it is unclear how these anomalies...
The role of occipital condyle and atlas anomalies on occipital cervical fusion outcomes in Chiari malformation type I with syringomyelia: a study from the Park-Reeves Syringomyelia Research Consortium.
OBJECTIVE
Congenital anomalies of the atlanto-occipital articulation may be present in patients with Chiari malformation type I (CM-I). However, it is unclear how these anomalies affect the biomechanical stability of the craniovertebral junction (CVJ) and whether they are associated with an increased incidence of occipitocervical fusion (OCF) following posterior fossa decompression (PFD). The objective of this study was to determine the prevalence of condylar hypoplasia and atlas anomalies in children with CM-I and syringomyelia. The authors also investigated the predictive contribution of these anomalies to the occurrence of OCF following PFD (PFD+OCF).
METHODS
The authors analyzed the prevalence of condylar hypoplasia and atlas arch anomalies for patients in the Park-Reeves Syringomyelia Research Consortium database who underwent PFD+OCF. Condylar hypoplasia was defined by an atlanto-occipital joint axis angle (AOJAA) ≥ 130°. Atlas assimilation and arch anomalies were identified on presurgical radiographic imaging. This PFD+OCF cohort was compared with a control cohort of patients who underwent PFD alone. The control group was matched to the PFD+OCF cohort according to age, sex, and duration of symptoms at a 2:1 ratio.
RESULTS
Clinical features and radiographic atlanto-occipital joint parameters were compared between 19 patients in the PFD+OCF cohort and 38 patients in the PFD-only cohort. Demographic data were not significantly different between cohorts (p > 0.05). The mean AOJAA was significantly higher in the PFD+OCF group than in the PFD group (144° ± 12° vs 127° ± 6°, p < 0.0001). In the PFD+OCF group, atlas assimilation and atlas arch anomalies were identified in 10 (53%) and 5 (26%) patients, respectively. These anomalies were absent (n = 0) in the PFD group (p < 0.001). Multivariate regression analysis identified the following 3 CVJ radiographic variables that were predictive of OCF occurrence after PFD: AOJAA ≥ 130° (p = 0.01), clivoaxial angle < 125° (p = 0.02), and occipital condyle-C2 sagittal vertical alignment (C-C2SVA) ≥ 5 mm (p = 0.01). A predictive model based on these 3 factors accurately predicted OCF following PFD (C-statistic 0.95).
CONCLUSIONS
The authors' results indicate that the occipital condyle-atlas joint complex might affect the biomechanical integrity of the CVJ in children with CM-I and syringomyelia. They describe the role of the AOJAA metric as an independent predictive factor for occurrence of OCF following PFD. Preoperative identification of these skeletal abnormalities may be used to guide surgical planning and treatment of patients with complex CM-I and coexistent osseous pathology.
Topics: Humans; Arnold-Chiari Malformation; Syringomyelia; Female; Male; Cervical Atlas; Child; Occipital Bone; Spinal Fusion; Adolescent; Atlanto-Occipital Joint; Treatment Outcome; Child, Preschool; Decompression, Surgical; Retrospective Studies; Cervical Vertebrae
PubMed: 38579359
DOI: 10.3171/2024.1.PEDS23229