Head, neck and vertebral column
David Heylings, Stephen Carmichael, Samuel Leinster, Janak Saada, Bari M. Logan, Ralph T. Hutchings in McMinn’s Concise Human Anatomy, 2017
The head and neck are the most intricate regions of the body, with many major nerves and blood vessels in close proximity to one another. In life the cranial cavity is lined by the dura mater, the outermost and toughest of the three membranes or meninges that cover the brain. The dura is firmly adherent to the periosteal lining of the cranial cavity, so there is normally no patent extradural space. The brain, consisting of the cerebrum, brainstem and cerebellum joined together by the midbrain, is the part of the central nervous system that lies within the cranial cavity of the skull. The functions of certain areas are clearly defined; among the most important are those that control the movements of skeletal muscles and those at which various kinds of sensory impressions reach consciousness. The vertebral artery enters the skull through the foramen magnum and unites with its fellow to form the single midline basilar artery.
Growth of the Cranial Vault
D. Dixon Andrew, A.N. Hoyte David, Ronning Olli in Fundamentals of Craniofacial Growth, 2017
The cranial vault is composed at birth of the paired frontal and parietal bones, two temporal squamae, and the unpaired supraoccipital part of the occipital bone, the occipital squama. At this stage the bones are separated by the fibrous tissue of the cerebral capsule and the spaces between them are gradually filled through sutural growth at the bone edges. Each separate cranial vault bone is enclosed in the periosteum, i.e., it lines each bone ectocranially and, via the bounding sutures, is continuous with the endocranial periosteum, specifically designed as dura mater. An adolescent spurt in the growth of the cranial vault has been observed to coincide with the peak velocity of height growth. The sutures are articulations within the craniofacial complex which are composed of five layers: pairs of cambial and capsular layers, and a middle looser zone. Morphogenesis and growth of the dermal bones of the cranial vault is dependent on the brain, whereas the facial bones are not.
The Spinal Cord and the Spinal Canal
Jean-Pierre Monnet, Yves Harmand in Pediatric Regional Anesthesia, 2019
The dorsal horns are well delineated. They reach posteriorly almost the dorsal limit of the spinal cord from which they are separated by a thin band of white matter, the marginal zone of Lissauer. The spinal cord is a cylindrical mass of nervous tissue that occupies the greatest part of the spinal canal, extending from the foramen magnum to end at the first to third lumbar vertebra. The spinal cord is covered with three membranes, or meninges, which contain a liquid, the cerebrospinal fluid. These meninges are pia mater, arachnoid and dura mater. The descending tracts of the spinal cord convey impulses for somatic movements, muscle tone, segmental reflexes, and visceral innervation. The spinal cord is a continuous unsegmented structure. The spinal cord presents several longitudinal furrows throughout its entire length. The ascending fibers of the spinal cord are organized into several fasciculi, mainly located in the funiculus posterior and the funiculus lateralis.
Preparation and characterization of a novel acellular swim bladder as dura mater substitute
Published in Neurological Research, 2019
Qing Li, Fenghua Zhang, Hongmei Wang, Tao Pan
Objectives: This paper aimed to develop a novel dura mater substitute made from swim bladders. Methods: The swim bladders were decellularized by diverse methods. The physical structure, residual DNA amount, mechanical properties and hemolysis rate were tested. The in vitro mouse embryonic fibroblast cells (MEFs) co-culture and in vivo dural repair surgery were performed to evaluate the biocompatibility of acellular swim bladder (ASBs). Results: The characteristics of different ASBs were evaluated, and the materials prepared via ‘freezing-thawing and DNase-I’ method showed the most appropriate features as dura mater substitute. The loosen fiber layer structure and three-dimensional porous structure were formed after decellularization. The residual DNA content was low (9.2 ± 2.0 ng/mg) and the mechanical properties could meet the clinical requirement (the maximum tensile strength was 34.77 ± 4.28 N and the maximum stitch tear strength was 7.15 ± 1.84 N). The hemolysis rate was up to 2.8 ± 0.15%. In the MEFs co-culture test, ASBs could support the adhesion, migration and proliferation of cells. The dural repair experiment demonstrated ASBs could prevent the leak of cerebrospinal fluid, and the materials were gradually replaced by autologous connective tissue. The novel dura mater substitute improved dura repair and regeneration without causing adhesion or severe inflammation. Discussion: The ASBs prepared via ‘freezing-thawing and DNase-I’ method had the ideal physical and biological properties as a dura mater substitute for clinical application.
Endoscopic approach for a delayed post-traumatic ethmoidal mucocele: a technical note
Published in British Journal of Neurosurgery, 2019
Mahmoud Messerer, Giulia Cossu, Roy Thomas Daniel
Objective: Delayed post-traumatic mucoceles are rare. We describe the surgical treatment of a post-traumatic ethmoidal mucocele with intra-orbital extension. Method: A uninostril endoscopic endonasal approach (EEA) was performed. The access was contralateral to the lesion to provide a wider lateral view. After a large sphenoid and ethmoid sinuses opening, the collection was drained and the optic nerve precociously identified. The orbital roof was eroded and the frontal dura mater directly visible. Conclusion: The uninostril contralateral approach allows a good exposure of the lateral fields and is conservative towards the nasal mucosa. A favorable skull base anatomy is the prerequisite for its efficacy.
Symptomatic pneumocephalus: A rare complication of discal herniation's surgery
Published in The Journal of Spinal Cord Medicine, 2019
Ghassen Gader, Nadhir Karmeni, Imed Ben Saïd, Hafedh Jemel
Context: We report the case of a 40-year-old woman with no pathological history, operated from an L4-L5 disc herniation by a left unilateral approach. The dura mater enveloping the left L5 root was accidentally injured at its lateral face causing a breach with CSF leakage. This breach could not be sutured. A few hours after waking, the patient presented an agitation followed by three generalized tonico-clonic seizures. Cerebral imaging revealed pneumocephalus. The patient was hospitalized in an intensive care unit. The symptoms gradually faded and the patient was discharged 3 days after surgery. Findings: Pneumocephalus is defined by the presence of air inside the skull. The symptoms of pneumocephalus are generally non-specific and varied, and this complication should also be kept in mind to prevent potentially severe course. The prevention of postoperative pneumocephalus depends on a well-defined strategy in the case of iatrogenic dural tear. Conclusions: Symptomatic pneumocephalus is a very rare complication in the course of lumbar surgery. Conservative therapy may be appropriate even in severe symptomatic manifestations.