Search

In 1975, ablation was initially used to treat chronic back pain and sciatica of unknown etiology as an alternative to the prior treatment of severing the dorsal rami via the intertransverse ligaments. It is a minimally invasive procedure that involves coagulation necrosis of afferent nociceptive signals via high-frequency waves (300 to 500 Hz). Currently, ablation is most commonly used to destroy the medial branches of the dorsal rami, which are responsible for facet-joint-mediated back pain. Ablative nerve blocks are commonly used in the treatment of chronic low back pain. However, their efficacy is mixed at best. The most benefit is the short term within the first four weeks following the procedure. However, significant relief of pain has been shown to last up to a year. Many studies do not show superiority over placebo for either pain relief or functional improvement. There is also evidence for its use for chronic discogenic back pain. However, the ablation of peripheral nerves that have a primary role in nociception for the treatment of pain is supported by the recent literature, particularly when symptomatology has been refractory to conservative management but is relieved with targeted blocks using short-acting anesthetic agents., (Copyright © 2022, StatPearls Publishing LLC.)

Pediatric craniopharyngioma could be considered one of the most complex neurosurgical pathologies in the pediatric population. The tumor's proximity to essential neural structures makes it challenging to manage. In children, these structures are still maturing and are extremely sensitive, both to the craniopharyngioma and the treatments that might be used for treatment can lead to further complications. This article reviews the most important aspects of this pathology in the pediatric population., (Copyright © 2022, StatPearls Publishing LLC.)

Neck pain is widespread and causes significant pain and disability. Workers with a history of neck pain account for up to 40% of work absenteeism. In the setting of cervical radiculopathy, because the nerve root of a spinal nerve is compressed or otherwise impaired, the pain and symptomatology can spread far from the neck and radiates to arm, neck, chest, upper back and/or shoulders. Often muscle weakness and impaired deep tendon reflexes are noted along the course of the spinal nerve., (Copyright © 2022, StatPearls Publishing LLC.)

The anterior inferior cerebellar artery (AICA) is one of the lateral branches of the basilar artery which supplies various structures of the posterior cranial fossa, most importantly the cerebellum and pons., (Copyright © 2022, StatPearls Publishing LLC.)

Conus and cauda equina tumors represent a unique group of tumors due to their specific location in the spinal canal. The conus medullaris forms the last portion of the spinal cord from where the axons of the distal nerve roots originate and where the spinal bowel and bladder centers are located. The cauda equina is the conglomeration of the nerve roots of the lumbar and sacral spinal nerves distally to the conus area. These two areas form a transition between the central nervous system and the peripheral nervous system. Conus lesions will primarily affect the central functions, while cauda lesions will affect peripheral functions. As these two areas are in close proximity, lesions in one area can affect the function of the other area. Lesions in each area give rise to specific deficits and are appropriately called cauda equina syndrome (CES) and conus medullary syndrome (CMS). In this review, the tumors causing these syndromes are described. Primary spinal cord tumors are less common than metastatic spinal tumors. Tumors of the spinal canal are classified in three ways depending on the tissue compartment in which they are found: 1. Extra-dural: arising outside of the dura mater. 2. Intra-dural/Extra-medullary: arising within the dura mater but outside of the neural tissue. 3. Intra-dural/Intra-medullary: arising within the dura mater and within the substance of the neural tissue. Tumors arising within the lumbar spine may involve either the vertebrae, the distal end of the spinal cord (conus medullaris), or the nerve roots (cauda equina). These tumors may be primary or metastatic, benign or malignant, and may have a broad range of presentations. The most common tumors involving the vertebrae are metastatic lesions with the most commonly involved area being the vertebral body. The most common tumors arising from the conus medullaris are ependymoma and astrocytoma. A metastatic lesion within the conus medullaris is possible but very uncommon. The most common tumor involving the cauda equina is a schwannoma., (Copyright © 2022, StatPearls Publishing LLC.)

Symptomatic thoracic discogenic pain syndrome (TDPS) is a rare phenomenon making it challenging to diagnose. The rarity of TDPS is attributed to the particular orientation, structure, and function of the thoracic spine in the vertebral column. The thoracic spine and sacrum exhibit kyphosis which is present at birth, while the cervical and lumbar spine exhibit fully developed lordosis around puberty. The lordotic nature of the cervical and lumbar spine allows the imaginary line of gravity to run through, allowing them to bear most of the weight of the of the axial skeleton as compared to the thoracic and sacral spine. Consequently, they are subject to a higher percentage of degenerated discs and subsequent discogenic pain syndrome. Between each vertebral body lies the intervertebral disc. The intervertebral disc is composed of two materials: the outer hard fibrous ring called the annulus fibrosis and an inner soft gelatinous core called the nucleus pulposus. The intervertebral disc functions to both absorb shock and allow flexibility of the vertebral column. As the body ages, the integrity of the intervertebral disc declines and causes the inner core of the disc to protrude through the outer layer. The effects of these will be either compression of the nerve roots or the spinal cord, giving rise to radicular or myelopathic symptoms. The majority of the thoracic disc herniation is asymptomatic, or the patient presents with nonspecific symptoms like chest wall pain, epigastric pain, upper extremity pain, and sometimes, a pain in the groin or the lower extremity causing the clinician to think of a more common problem than a thoracic disc herniation. While the rare nature, coupled with the atypical presentation, may lead to delay in diagnosis, it has been significantly cited in the literature that MRI can be very useful in diagnosing thoracic disc herniations (TDHs). The majority of asymptomatic TDHs were often diagnosed due to incidental MRI findings. Treatment of thoracic discogenic pain syndrome is conservative but sometimes surgical. Surgical interventions, with surgical intervention associated with many complications., (Copyright © 2022, StatPearls Publishing LLC.)

Total blindness  is a term used to describe those who have complete lack of light perception, documented as no light perception (NLP). Only about 15% of people with eye disorders have total blindness, the majority of those with visual impairment have some level of vision.  Low vision is a term used to describe those whose vision cannot be fully corrected by conventional method such as glasses, contact lenses, medicine, surgery, magnification aids or assistive technology.  Visual impairment is a functional term to describe those whose decreased visual function interferes with the ability for one to perform their activities of daily living, such as reading, driving, and watching TV. Visual impairment is defined based on function, instead of using visual acuity or visual field cutoff values. Visual impairment includes those who have low vision or who are blind. The types of visual symptoms you may experience include: Blurred vision. Hazy/cloudiness. Wavy or spots in central vision. Restricted peripheral vision. Poor night vision. Difficulty seeing colors. Legal blindness is a term defined by the United States Social Security Administration (SSA) to determine those who are eligible to receive disability benefits, tax exemption programs, and rehabilitation training. SSA uses visual acuity or visual field results to determine this eligibility. A person is considered legally blind if he/she has central visual acuity of 20/200 or worse in the better-seeing eye with best correction (using glasses or contact lenses) at a distance, or if he/she has visual field restriction where the widest diameter is 20 degrees or less in the better-seeing eye. The tests used to measure visual acuity or visual fields have been outlined as follows: : Visual acuity testing for distance is carried out using Snellen visual acuity chart or another test that is comparable to the Snellen methodology. In 2007, SSA updated the criteria for measuring the visual acuity by allowing newer low vision test charts to be used instead of Snellen acuity charts alone. Under this update, if a person cannot read at least one letter on the 20/100 line, he or she will be classified as legally blind. . Acceptable tests for visual field testing include automated static perimetry such as Humphrey Field Analyzer (HFA) 30-2, HFA 24-2, and Octopus 32, kinetic perimetry such as Goldmann perimetry or HFA "SSA Test Kinetic." Screening tests including confrontation tests, tangent screen tests, and static screening tests are not accepted forms of testing to determine legal blindness. World Health Organization classifies visual impairment into the following categories based on visual acuity or visual field of the better seeing eye.  Normal: 20/10-20/25 Near Normal visual impairment: 20/30-20/60 Moderate visual impairment: 20/70-20/160 Severe visual impairment: 20/200-20/400, or 11-20 degrees on visual field Profound visual impairment: 20/500-20/1000 visual acuity, or 6- 10 degrees on visual field Near total visual impairment: Counting fingers, Hand motion, Light perception, or 5 degrees or less on visual field Total visual impairment: No light perception , (Copyright © 2022, StatPearls Publishing LLC.)

The corpus callosum is the primary commissural region of the brain consisting of white matter tracts that connect the left and right cerebral hemispheres. It is composed of approximately 200 million heavily myelinated nerve fibers that form homotopic or heterotopic projections to contralateral neurons in the same anatomical layer. During infancy, the corpus callosum expands rapidly due to an increase in the number of axons, axon diameter, and myelin. Although the development of the corpus callosum is complete by age four, growth continues until the third decade of life at a much slower rate. Anatomically from anterior to posterior, the corpus callosum is composed of four parts based on previous histological findings: the rostrum, genu, body, and splenium, each responsible for connecting distinct areas of the cortex. The isthmus refers to the narrow region between the body and splenium in the posterior aspect of the corpus callosum. Fibers of the genu cross over and give rise to the forceps minor, a connection between regions of the frontal cortices. The fibers of the splenium move posteriorly and contribute to the forceps major, providing a connection between the occipital lobes. The body fibers form the corona radiata as well as other large white matter pathways as they move transversely through the cerebral cortex. Finally, the orbital regions of the frontal lobes connect via the rostral fibers. Due to its anatomical location, the corpus callosum is strongly related to the fornix and lateral ventricles. In conjunction with the fornix, the corpus callosum forms a physical barrier to separate the two lateral ventricles., (Copyright © 2022, StatPearls Publishing LLC.)

Tumors in the spine comprise about 15% of all tumors in the central nervous system. They usually are benign and cause symptoms primarily through compression of the spinal cord and nerves. Spinal tumors can be classified into three groups, based on their locations: extradural, intradural-extramedullary, and intramedullary. Extradural tumors are most common, as they occupy the vertebrae body or structures outside the dura. They are most commonly metastatic. Intradural extramedullary tumors are the second most common and come from the leptomeninges or nerve roots. These tumors are located inside the dura but external from the spinal cord, exemplified by meningiomas or neurofibromas. The least common (2 to 5%) are intramedullary spinal cord tumors (IMSCT); these arise from the spinal cord proper, leading to invasion and destruction of the gray and white matter. Ependymomas and astrocytomas are the most commonly encountered intramedullary spinal cord tumors, followed by hemangioblastomas. Other entities include lipomas, germ cell tumors, gangliogliomas, germinomas, lymphomas, and metastases., (Copyright © 2022, StatPearls Publishing LLC.)

Brain abscess is a focal area of necrosis with a surrounding membrane within the brain parenchyma, usually resulting from an infectious process or rarely from a traumatic process., (Copyright © 2022, StatPearls Publishing LLC.)

The brain vasculature provides the nutrients necessary for the well functioning of the central nervous system (CNS). Anatomical and angiographic studies considerably detail the topography of the arterial architecture and the related relationships. We review the arterial blood supply to the brain. Awareness of its normal anatomy and its common variations and anomalies are critical for the diagnostic and treatment of stroke and associated vascular disorders., (Copyright © 2022, StatPearls Publishing LLC.)

A ventriculoperitoneal (VP) shunt is a cerebral shunt that drains excess cerebrospinal fluid (CSF) when there is an obstruction in the normal outflow or there is a decreased absorption of the fluid. Cerebral shunts are used to treat hydrocephalus. In pediatric patients, untreated hydrocephalus can lead to many adverse effects including increase irritabilities, chronic headaches, learning difficulties, visual disturbances, and in more advanced cases severe mental retardation.. After placement, if it malfunction, excess CSF accumulated which can increase the intracranial pressure resulting in cerebral edema and ultimately herniation. These shunts drain the CSF into the peritoneal cavity, the atrium, or the pleura; thus, appropriately called ventriculoperitoneal, ventriculoatrial, and ventriculopleural shunts. A shunt consists of a ventricular catheter that is connected to a valve and then connected to a distal catheter. The distal end of a VP shunt is placed in the peritoneal cavity. The main differences between shunts are the type of valve used, and whether the valve is programmable or not. Advances in the biotechnologies are leading to progressive changes in the shunt components. These advanced components are expected to reduce shunt malfunctions and optimize neurosurgical patient care., (Copyright © 2022, StatPearls Publishing LLC.)

Glioma is the most common form of central nervous system (CNS) neoplasm that originates from glial cells. In the United States, there are six cases of gliomas diagnosed per 100,000 people every year. Gliomas are very diffusely infiltrative tumors that affect the surrounding brain tissue. Glioblastoma is the most malignant type while pilocytic astrocytomas are the least malignant brain tumors.  In the past, these diffuse gliomas were classified into different subtypes and grades based on histopathologies such as a diffuse astrocytoma, oligodendrogliomas, or mixed gliomas/oligoastrocytomas. Recently, gliomas were classified based on molecular and genetic markers. These advances have more specific prognostic and therapeutic benefits for patients with gliomas. In addition to molecular and genetic markers, gliomas are classified in grade I to IV based on the degree of proliferation indicated by the mitotic index and the presence or absence of necrosis. , (Copyright © 2022, StatPearls Publishing LLC.)

Diffuse axonal injury (DAI) is a type of traumatic brain injury (TBI) that results from a blunt injury to the brain. In the United States, traumatic brain injury is a leading cause of death and disability among children and young adults. The Center for Disease Control and Prevention (CDC) estimates that there are over 1.5 million reported cases of traumatic brain injury every year in the United States. Traumatic brain injury is classified as mild, moderate, and severe based on the Glasgow coma scale (GCS). Traumatic brain injury patients with GCS of 13 to 15 are classified to be mild, which includes the majority of traumatic brain injury patients. Patients with a GCS of nine to 12 are considered to have a moderate traumatic brain injury, while patients with a GCS below eight are classified as having a severe traumatic brain injury. The GCS measures the following three functions: 1. Eye Opening (E): 4-spontaneous, 3-to voice, 2-to pain, 1-none. 2. Verbal Response (V):  5-normal conversation, 4-oriented conversation, 3-words, but not coherent, 2-no words, only sounds, 1-none. 3. Motor Response (M):  6-normal, 5-localized to pain, 4-withdraws to pain, 3-decorticate posture, 2-decerebrate . Diffuse axonal injury (DAI) primarily affects the white matter tracts in the brain. Clinically, patients with DAI can present in a spectrum of neurological dysfunction. This can range from clinically insignificant to a comatose state. However, most patients with DAI are identified to be severe and commonly have a GCS of less than 8. A diffuse axonal injury is a clinical diagnosis., (Copyright © 2022, StatPearls Publishing LLC.)

Craniopharyngiomas are rare, benign tumors of the central nervous system. Craniopharyngiomas are epithelial tumors that typically arise in the suprasellar area of the brain, extending to involve the hypothalamus, optic chiasm, cranial nerves, third ventricle, and major blood vessels. It can produce a wide array of symptoms such as headaches, nausea, and vomiting, visual and endocrine disturbances. It represents a special challenge for the physicians treating it; these physicians commonly include neurosurgeons, neuro-ophthalmologists, neurologists, endocrinologists, and pediatricians. Curative surgeries are extremely difficult due to their location and infiltration into the surrounding structures. Further, the quality of life is compromised due to the development of multiple complications, including panhypopituitarism, visual problems, obesity, and mental disorders., (Copyright © 2022, StatPearls Publishing LLC.)

Despite the advances in pharmacotherapy for treating some psychiatric disorders like anxiety disorders, obsessive-compulsive disorder, depression, and schizophrenia, many patients become refractory and will not respond to pharmacologic treatments. Clinicians are beginning to reconsider neuromodulation surgery as a last resort for the treatment of these patients. Neurosurgical interventions aimed at treating psychiatric disorders are grouped into destructive (ablative psychosurgery) or selective stimulation (neuromodulation psychosurgery). Neuromodulation surgery involves implanting a device in the brain that modulates the neural networks within the brain. The use of surgery for the treatment of psychiatric diseases is not a new concept. Historically, the concept of psychosurgery always raised general skepticism and stigma because of the way that it was used in the past with a high rate of complications and mortalities, but usually with little improvement in patients’ functionality. In 1881, Gottlieb Burckhardt, a Swiss psychiatrist, reported on six patients that he performed surgery to treat aggressive behavior and hallucinations with partial results. Three decades later, Puusepp operated in 1910 on three manic-depressive patients by interrupting the frontal fibers to the parietal cortex. Fulton and Jacobsen's classical experiments on two chimpanzees that received frontal lobe surgical ablation to improve neurotic behaviors were an inspiration for subsequent human ablative procedures. In 1935, a Portuguese neurologist named Egas Moniz first introduced a surgical procedure called prefrontal leucotomy. Moniz believed that abnormal connections to the frontal lobe caused some psychiatric problems and that surgically removing the white fibers connecting the frontal lobe with the rest of the brain will help mental health conditions. Moniz technique was later widely utilized in Europe and the United States. Moniz was awarded the Nobel Prize in 1949 for his contributions. In the United States, prefrontal leucotomy was initially used, but modified by an American neurosurgeon named Walter Freeman, who developed a transorbital leucotomy procedure. Unlike the original lobotomy that involved an open surgery, transorbital leucotomy was a minor surgery. It lasted about 10 to 20 minutes and aimed at separating the frontal lobe from the thalamus by accessing the brain through the back of the orbits with a sharp instrument similar to an ice pick. Clinicians often used this treatment even though, at the time, there was not much data to evaluate the effectiveness of this method, and because of the lack of alternative treatment for patients who had debilitating mental health problems. Later, retrospective studies showed that while Dr. Freeman's approach helped calmed some severely agitated patients, many ended up with numerous complications. In the late 1950s, pharmacotherapy was introduced and changed the approach in treating psychiatric conditions. Chlorpromazine was the first U.S. Food and Drug Administration approved psychotropic drug. While pharmacotherapy led to psychosurgery quietus, physicians laid the groundwork for the development of stereotactical microsurgery techniques. Speigel and Wycis developed the concept of stereotactic surgery to perform precise ablative lesions in deep areas of the brain in 1947. In 1962, Foltz and White used this technique for stereotactic anterior cingulotomy. Furthermore, the rapid development of numerous modalities helped to understand the structure and function of the brain. These new advances, coupled with the frustrations of the significant percentage of patients not responding to pharmacotherapy and positive results in the use of neuromodulation surgery like deep brain stimulation (DBS) in the treatment of movement disorders like Parkinson's disease, leaded clinicians to revisit the use of neuromodulation surgery for the treatment of psychiatric disorders. However, professionals debated whether these techniques will be used only as a last resort for the treatment of refractory psychiatric symptoms, or if they will be used for other purposes like to modify the cognition of healthy individuals.  Ethical requirements and guidelines for the procedures began to appear in physician's societies., (Copyright © 2022, StatPearls Publishing LLC.)

The lumbar spine in the sagittal plane should maintain an alignment in which each vertebral body is aligned with the vertebral body above and below.  In other words, the anterior inferior endplate of the vertebral body above should be aligned with the anterior superior endplate of the vertebral body below.  Spondylolisthesis occurs when there is an anterior translation or “slippage” of one vertebral body relative to its caudal vertebral body. In most cases, symptoms associated with spondylolisthesis are chronic.  The primary symptom of chronic spondylolisthesis is back pain, with or without leg pain. When spondylolisthesis occurs acutely in the setting of traumatic or metastatic tumors, patients can present with neurological examination deficits including a loss of bowel and bladder function. The classification system utilized to categorize the degree of subluxation of the vertebral bodies is the Meyerding Classification, which quantifies the percentage of subluxation of the vertebral body above on the vertebral body below. Classification of Spondylolisthesis is based on the degree of slippage in the lumbar spine. Grade 1 is less than 25%, Grade 2 is 25% to 50%, Grade 3 is 50% to 75%, Grade 4 is 75% to 100%, and Spondyloptosis is > 100% . There are many causes of spondylolisthesis including congenital, degenerative, traumatic, pathologic, iatrogenic, and isthmic. Isthmic spondylolisthesis, which will be the topic of this discussion, refers to a defect in the pars interarticularis that then results in anterior subluxation over time, most commonly at L5-S1 followed by L4-5.  The resulting anterior subluxation can produce back pain, central canal stenosis, and lateral recess or foraminal stenosis., (Copyright © 2022, StatPearls Publishing LLC.)

Brachial plexitis is a condition characterized by acute onset of shoulder pain followed by weakness and/or sensory loss of the shoulder and/or upper extremity. Dreschfeld first described it in 1887. Multiple reports further described the condition. The most important one out of these was the report of 136 patients by Parsonage and Turner in 1948. It was this report that strongly characterized the clinical history of the condition. Since then, the condition has been known by many different names such as Parsonage-Turner syndrome, neuralgic amyotrophy, acute brachial neuropathy, acute brachial plexitis, idiopathic brachial plexopathy, idiopathic brachial neuritis,  paralytic brachial neuritis, and brachial radiculitis, among others., (Copyright © 2022, StatPearls Publishing LLC.)

Spinal metastases are the most common tumors of the spine, comprising approximately 90% of masses encountered with spinal imaging. Spinal metastases are more commonly found as bone metastasis, although they are not limited to bone metastasis, and approximately 20% present with symptoms of spinal canal invasion and cord compression. Within the spinal column, metastasis is more commonly found in the thoracic region, followed by the lumbar region, while the cervical region is the least likely place professionals find metastasis . While evaluating spinal metastasis on MRI imaging, a defining feature of these lesions is the sparing of intervertebral disc space. This disc space is almost always involved during infection. Metastatic diseases to the spine spread through several different routes which include venous hematogenous spread versus the arterial spread, direct tumor extension, and lastly lymphatic spread. Among the routes mentioned above, hematogenous spread through Batson’s plexus system is the most common pathway for tumor embolization and spinal invasion. The following summary emphasizes the essential knowledge necessary to have while treating patients with spinal metastasis ., (Copyright © 2022, StatPearls Publishing LLC.)

Overall, about 20% of strokes are hemorrhagic, with SAH and Intracerebral hemorrhage (ICH) each accounting for 10%. Subarachnoid space is described as a space between the arachnoid membrane and the pia mater. It consists of the cerebrospinal fluid and the blood vessels that supply different areas of the brain. A subarachnoid hemorrhage (SAH) is defined as the accumulation of blood in the space between the arachnoid membrane and the pia mater around the brain referred to as the subarachnoid space.  The etiology of SAH can be either nontraumatic (about 85% are secondary to aneurysm rupture) or traumatic in nature. In this review, we shall discuss the various aspects of nontraumatic SAH. Most nontraumatic causes of SAH (~ 85%) are caused by the rupture of an intracranial aneurysm. The remaining 15-20% of patients presenting with SAH do not have a vascular lesion on the initial digital subtraction angiography. Regardless of the cause, a SAH is often a devastating clinical event with substantial mortality and high morbidity among survivors. Prehospital care is critical and involves triaging the patient with attention to the airway, breathing, and circulation to a hospital with neurocritical/neurosurgical expertise. The classic presentation is often a sudden-onset, severe headache typically described as the "worst headache of my life". Treatments are based on randomized controlled studies and prospective cohort studies. A SAH has a prolonged course of illness and is complicated by various factors not limited to seizures, vasospasm, hydrocephalus, and delayed cerebral ischemia (DCI). , (Copyright © 2022, StatPearls Publishing LLC.)

Traumatic lumbar spondylolisthesis, also known as traumatic lumbar locked facet syndrome, is an acute anterior shift of a lumbar vertebral body (L1 – L5) over another. This rare injury arises from complex trauma and high-energy mechanisms resulting in pathoanatomical changes at the intervertebral articulations. Usually, lumbar spondylolisthesis is encountered in degenerative diseases. Moreover, reported cases of traumatic lumbar spine injuries commonly involve either the thoracolumbar or lumbar sacral region. Herein, we review the anatomy of lumbar vertebras emphasizing the intervertebral joints and the mechanism of injuries. Next, we discuss radio-clinical presentations as well as management options., (Copyright © 2022, StatPearls Publishing LLC.)

Spinal stenosis is a condition in which the nerve roots are compressed by a number of pathologic factors, leading to symptoms such as pain, numbness, and weakness. The upper neck (cervical) and lower back (lumbar) areas most frequently are affected, although the thoracic spine also can be compressed most frequently by a disk herniation. Three different anatomic sites within the vertebral canal can be affected by spinal stenosis. First, the central canal, which houses the spinal cord, can be narrowed in an anterior-posterior dimension, leading to compression of neural elements and reduction of blood supply to the spinal cord in the cervical area and the cauda equina in the lumbar area. Secondly, the neural foramen, which are openings through which the nerve roots exit the spinal cord, can be compressed as a result of disk herniation, hypertrophy of the facet joints and ligaments, or unstable slippage of one vertebral body relative to the level below. Lastly, the lateral recess, which is seen in the lumbar spine only and is defined as the area long the pedicle that a nerve root enters just before its exit through the neural foramen, can be compressed from a facet joint hypertrophy.  Depending on the level of the spine affected, each type of compression can lead to different symptoms that warrant a particular treatment modality. Most patients will experience some type of pain associated with the spine but luckily, even without surgery, the majority will have an uneventful recovery. Only 1-3% will have a herniated disc and less than 2% will have compression of a nerve root. Spinal stenosis is common with aging but predicting which individual will develop symptoms is not possible. In most cases, the degenerative process can be controlled by changes in lifestyle., (Copyright © 2022, StatPearls Publishing LLC.)

The cavernous sinus is part of the brain’s dural venous sinus and contains multiple neuro-vasculatures. It is situated bilaterally to the sella turcica and extends from the superior orbital fissure anteriorly to the petrous part of the temporal bone posteriorly, and is about 1 cm wide and 2 cm long. The venous blood that flows to the cavernous sinus is from the superior and anterior ophthalmic veins, superficial middle cerebral vein, and sphenoparietal sinus. The communication between the left and right cavernous sinuses is made by the intercavernous sinuses anterior and posterior to the infundibulum of the pituitary gland., (Copyright © 2022, StatPearls Publishing LLC.)

The presence of focal neurologic findings or mental status changes is predictive of complications following trauma. A neurologic examination helps to localize and lateralize lesions due to traumatic head or spine injury. The physical examination in the setting of significant trauma must be assessed rapidly, is individualized based on the patient's medical stability, combativeness, and type of injuries, and is often performed under chaotic circumstances. , (Copyright © 2022, StatPearls Publishing LLC.)

The hippocampus is the "flash drive" of the human brain and is often associated with memory consolidation and decision making, but it is far more complex in structure and function than a flash drive. The hippocampus is a convex elevation of gray matter tissue within the parahippocampal gyrus inside the inferior temporal horn of the lateral ventricle. One can describe it more holistically as a curved and recurved sheet of the cortex that folds into the temporal lobe's medial surface. The hippocampus has three distinct zones: the dentate gyrus, the hippocampus proper, and the subiculum—the dentate gyrus and hippocampus proper form two C-shaped rings that interlock. The subiculum is thus a transition zone, linking the hippocampus proper with the dentate gyrus. The parahippocampal gyrus and cingulate sulci are located on the medial surface of the hemisphere, forming a C-shaped ring. The medial temporal lobe cortex includes major subdivisions such as the hippocampus and the entorhinal cortex. This five-centimeter-long hippocampus (from the anterior end at the amygdala to the posterior end near the splenium of the corpus callosum) divides into a head, body, and tail. the head is expanded and bears two or three shallow grooves called pes hippocampi. The head of the hippocampus is part of the posterior half of the triangular uncus and is separated inferiorly from the parahippocampal gyrus by the uncal sulcus. The alveus, which is the surface of the hippocampus, is covered by the ependymal inside the ventricular cavity. The fornix, which is the main outflow bundle out of the hippocampus, wraps around the thalamus, where it then becomes separated by the choroidal fissure and the choroid plexus. The hippocampus contains parts like the fimbria, crus, body, and column—the fimbria forms where alveus fibers converge along the medial portion of the lateral ventricle's inferior horn. The white matter of the fimbria separates to form a crux of the ipsilateral fornix at a point beyond the splenium of the corpus callosum. The Cornu Ammonis (CA) is a seahorse-like or ram's horn-like structure that describes the different layers of the hippocampus. There are four hippocampal subfields CA1, CA2, CA3, and CA4. CA3 and CA2 border the hilus of the dentate gyrus on either side. CA3 is the largest in the hippocampus and receives fibers from the dentate granule cells on their proximal dendrites. The pyramidal cell layer is about ten cells thick., (Copyright © 2022, StatPearls Publishing LLC.)

A spinal epidural abscess(SEA) is a suppurative central nervous system infection involving the space between the spinal dura and vertebral periosteum. Giovanni Morgagni first described SEA in 1761. Although classically, patients with spinal epidural abscesses present with midline back pain, fever, and neurologic deficits, presentations of this disease process can be highly variable. A spinal epidural abscess is difficult to diagnose if clinical suspicion is not high. When left untreated spinal epidural abscess can cause significant morbidity and mortality. Thus any clinical concern for this diagnosis requires prompt evaluation and treatment. Diagnosing and managing spinal epidural abscesses are greatly aided by the advent of modern radiological techniques, including computerized tomography and magnetic resonance imaging (MRI)., (Copyright © 2022, StatPearls Publishing LLC.)

The spinal cord is a nervous tissue bundle from the medulla oblongata in the brainstem to the lumbar region, and the vertebral column protects it. The vertebral column consists of seven cervical, 12 thoracic, five lumbar, five sacral, and three to five coccygeal vertebrae. The cervical vertebrae are numbered C1 to C7 from the base of the skull to the thoracic vertebrae. The structure of C1, C2, and C7 have distinctive properties compared to C3 to C6. The anatomy of C3 to C6 consists of a central body, the pedicles anteriorly, lamina posteriorly completing a ring around the spinal cord. Motion is mainly posteriorly at the superior and inferior articular processes with the vertebral artery, vein, and sympathetic plexus running through anterior foramen transversarium of the transverse process. C1 (atlas) connects the skull and spine mainly by ligamentous attachments. It has no body due to fusion with axis (C2) vertebrae which acts as a pivot for the atlas to rotate. The most distinctive feature of C2 vertebrae is the strong odontoid process (dens) that rises perpendicularly from the upper surface of the body. The body is deeper in front than behind, and prolonged downward anteriorly, so there is an overlap of the upper and front part of the third vertebra. C7 has a distinctive long and prominent spinous process, which is palpable from the skin surface. The transverse processes are larger in size. The upper surface of each has a shallow sulcus for the eighth cervical nerve. A cervical disc separates each cervical vertebrae. The composition is of inner nucleus pulposus of mucoprotein gel and outer annulus fibrosus. This composition allows for flexibility and mobility of the cervical spine. There is increased the risk of injury in cervical spine compared to the more fixed thoracic spine., (Copyright © 2022, StatPearls Publishing LLC.)

The foramen spinosum is a small circular foramen present posterolateral to the foramen ovale in the greater wing of the sphenoid. The greater wing of the sphenoid is a bony projection arising from both sides of the sphenoid body forming a part of the floor of the middle cranial fossa. Jakob Benignus Winslow coined the term foramen spinosum because of the foramen's location in the spinous process of the greater wing of the sphenoid., (Copyright © 2022, StatPearls Publishing LLC.)