Arnold Chiari Malformation

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Some Chiari Vocabulary

The Vocabulary Below I Debra Is Not Claiming The Definitions To Be
Correctly Exact As I am Not A Doctor.  I Debra Is Not Responsible
For Any Terminology Or Actions Anyone Reading May Take


Always Seek The Advice Of A Medical Professional


Acetazolamide - also known as Diamox; medicine used to lower elevated ICP

Acute - Having rapid onset, severe symptoms, and a short course; not chronic.

Afferent Pathways - nerve paths that carry signals from the periphery - like the hand - to the spinal cord and brain

Allodynia - pain in response to something that should not cause pain, like a light touch

Amyotrophic - Muscle wasting.

Antimetic - drug used to control nausea and vomiting

Apnea - Cessation of breathing noted by color changes, pallor and/or cyanosis, and lack of chest wall movement. To stop breathing intermittently, may be due to compression on the brainstem. Central sleep apnea is due to a delay in the nerve signal from the brain to breathe .Obstructive sleep apnea is due to an obstruction in the throat

Arachnoid - the middle of the three membranes covering the brain, appears to resemble a spider web. There are 3 layers of covering of the brain and spinal cord- the pia, arachnoid and dura.

Arachnoiditis - inflammation of the arachnoid

Aseptic Meningitis - Inflammation of the membranes (meninges) that cover the brain and spinal cord. NOT an infection.

Aspirate - the inhalation of fluids into the lungs. (Inability to swallow properly can allow this to occur.)

Ataxia - inability to coordinate muscles in voluntary movement movement. Stumbling when walking, or inability to maintain a fluid gait when asked to walk a straight line.

Atrophic - changes in the muscle that create an appearance of being wasted away

Atrophy - Wasting away of the muscle, often due to lack of use or inability to exercise a muscle.

Atypical - Not typical

Autologous - derived, or taken, from a person's own body ( as some of the material used in duragrafts)

Basilar Invagination - condition, sometimes associated with Chiari, where the C2 vertebra is displaced upward, potentially compressing the brainstem

Brainstem - the lowest part of the brain connecting with the spinal cord and controlling automatic functions such as breathing and swallowing

Catheter - small, soft plastic tube used to drain fluid. A Foley catheter is often inserted into the bladder for surgery. A shunt catheter can be inserted into a syrinx or the ventricles of the brain.

Caudal - towards the tail, in the case of CSF flow, from the skull to the spine

Central Canal - center of the spinal cord, so named because it starts as a hollow tube which closes in most people as they age

Central Nervous System (CNS) - The part of the nervous system consisting of the brain and spinal cord which coordinates the entire nervous system of the body.

Cerebellar Cortex - The outer layer of the cerebellum

Cerebellar Speech - Abnormal speech patterns seen in people who have a disease of the cerebellum; a slow, jerky, and slurred speech that may come and go or it may be unvaried in pitch.

Cerebellar Tonsils - Two bulges at the bottom of the cerebellum, named tonsils because of their shape.

Cerebellomedullary - Refers to the area where the cerebellum and the medulla are in the brainstem

Cerebellum - Lower portion of the brain, that lies in the posterior fossa, and is responsible for coordination of skeletal muscle movement.

Cerebral Aqueduct - A narrow conduit (tube), between the third and the fourth ventricles; located in the midbrain. CSF moves from the third ventricle through the cerebral aqueduct to the fourth ventricle.

Cerebral Cortex
- The outer layer of the cerebrum.

Cerebral Hemisphere - One of the large, paired structures that together constitute the cerebrum of the brain.

Cerebral Spinal fluid (CSF) - Fluid that occupies the ventricles of the brain, subarachnoid space of the meninges, and the central canal of the spinal cord.Acts as a shock absorber for the brain.

Cerebrum - Portion of the brain that occupies the upper part of the cranial cavity.

Cerebrospinal Fluid (CSF) - The clear colorless fluid which bathes the surface of the brain and spinal cord.

Cervical - Pertaining to the area at the top of the neck where there are seven cervical vertebra. They are counted from top to bottom. At the top there is the first cervical vertebra often referred to as C1, then the second C2 than C3,C4,C5,C6, and C7.

Charcot Joint - A type of diseased joint associated with varied conditions; syringomyelia among them, which involves disease or injury to the spinal cord. It is characterized by hypermobility. Decalcification of bone on joint surfaces occurs accompanied by overgrowth of bone. This results in deformity and instability of the joint. Pain is uncharacteristic, but may occur.

Chiari Malformation - condition where the cerebellar tonsils are displaced out of the skull area into the spinal area, causing compression of brain tissue and disruption of CSF flow

Chiari II - more severe form of malformation which involves descent of parts of the brainstem and is usually associated with Spina Bifida

Chronic - Long lasting; a disease having a long course; not acute.

CINE MRI - type of "motion picture" MRI which can show CSF flow ...originally developed for heart related testing

Cisterna Magnum - A cavity, a dilation of the subarachnoid space which is located between the cerebellum and the medulla. It receives CSF from the fourth ventricle via the medial foramen of Magendie.

Clonus - A series of alternating muscle contractions and partial relaxations that produce a convulsive spasm.

CM - Chiari malformation.

Color Doppler Ultrasound (CDU) - type of ultrasound which can detect flow of blood and CSF... can be used during surgery for more accurate evaluation of improvements in CSF flow

Congenital - Existing at birth; usually refers to certain mental or physical traits, peculiarities, or diseases; is a more general term than hereditary since congenital includes conditions due to influences arising during gestation.

Cranial Nerve - Nerve that arises from the brain .

Craniectomy - The excision (removal) of part of the skull

Craniocervical Junction - the area where the skull and spine meet

CT Scan - A specialized X-ray that takes images around the body that are reconstructed by a computer to give a more detailed image than a standard x-ray.

Dandy Walker - A syndrome characterized by hydrocephalus in infants associated with an abnormal closure of the passage at the foramina of Luschka and Magendie.

Decompression - To take pressure off, relieve pressure.

Doplopia - symptom of seeing double, or double vision

Dura - The outermost, toughest and most fibrous of the three membranes covering the brain and spinal cord.

Dura Mater - Tough outer layer of the membranes surrounding the brain and spinal cord.

Duraplasty - a surgical technique where a patch is sewn into the dura to allow for more room for the brain

Dysphagia - Inability to swallow or difficulty in swallowing.

Ectopia - abnormal herniation, displacement or hang down of tissue

Electrocautery - a small instrument that uses heat and is used in many surgeries to stop bleeding.

Epidural Space - The space between the dura and the bone of the vertebral canal.

Filum Terminale - A long slender filament at the end of the spinal cord.

Foramen Magnum - A large opening in the base of the occipital bone through which the spinal cord becomes continuous with the medulla oblongata.

Fossa - A depression on the surface of the end of a bone

Fusion - surgical procedure where vertebra are joined together using bone grafts and often appliances such as rods, screws, etc.

Gait - Manner of walking.

Horner Syndrome - A condition evidenced by contraction of the pupil, partial drooping of the eyelid, recession of eyeball back into socket, and sometimes loss of sweating over the affected side of the face, due to paralysis of the cervical sympathetic nerve trunk.

Hydrocephalus - An abnormal accumulation of cerebrospinal fluid in the cavities (ventricles) of the brain, distending them and stretching and thinning the brain tissue covering them. An increased accumulation of CSF within the ventricles of the brain, resulting from interference with normal circulation and with absorption of the fluid, especially from destruction of the formation of the foramina of Magendie and Lushka. This may also result from developmental anomalies, infection, injury, or brain tumors.

Hydromyelia - having a cyst in, or swelling of, the central canal; sometimes used interchangeably with syringomyelia

ICP- Intracranial pressure.

Idiopathic - due to an unknown cause/causes

Klippel-Fei Syndrome - a congenital condition where 2 or more cervical vertebra are fused together; this is often associated with other neurological conditions

Increased Intracranial Pressure (ICP) - An increase in CSF production or blockage resulting in pressure on the brain. The skull cannot expand to accommodate the pressure which leads to symptoms.

Laminectomy - The surgical removal of a portion of the bone comprising a vertebra. It may be used in detethering surgery to gain access to the tethered cord site. This is also done in some decompressions.

Lumbar puncture - a procedure where a hollow needle is inserted into the spinal area (near the base) in order to measure/relieve pressure or withdraw CSF for testing . Special protocol should be employed when this is done on a person with a chiari malformation.

Medulla Oblongata - Portion of the brain stem located between the pons and the spinal cord.

Meninges - Three layers of membrane covering the brain and spinal cord. Cerebrospinal fluid occupies the space between two of the layers.

Meningitis - Infection or swelling of the membrane (meninges) that covers the brain and spinal cord.

Meningocele - is a developmental anomaly. . It is defect of the neural tube, the embryonic structure that gives rise to the spinal cord and vertebral column. This defect leads to protrusion of the spinal cord and its coverings through a defect in the skin.

MRI - Magnetic Resonance Imaging; diagnostic device which uses a strong magnetic field to create images of the body's internal parts. It was the development of this instrument which led to more understanding of chiari, in general.

Myelocystomeningocele - A congenital defect whereby the membranes and spinal cord protrude within a sac through a defect in the vertebral column.

Neural Tube - The initiator of the central nervous system. Formed by the fusion of the two upturned neural folds formed by the edges of the neural plate, giving rise to the brain and spinal nerve cord.

Nystagmus - Constant, involuntary, cyclical movement of the eyeball. Movement may be in any direction. May be constant or periodic.. Frequently seen with chiari.

Obex - A thin, crescent shaped band of tissue at the end position of the fourth ventricle. The point on the midline of the top surface of the medulla oblongata that marks the tail end of the fourth ventricle.

Occipital - The back of the head.Occipital Bone - The cuplike bone at the back of the skull, marked by a large opening known as the foramen magnum.

Peritoneum - The membrane covering the visceral organs and lining the abdominal cavity.

Posterior Fossa - Depression in the back of the skull.

PND - is a painful neuropathic disorder; any painful disorder where the pain is caused by nerve damage; such as diabetic neuropathy or post-herpetic neuralgia

Papilledema - swelling/bruising of the optic nerve due to increased ICP

Platybasia - A developmental anomaly of the skull or an acquired softening of the skull bones so that the floor of the posterior cranial fossa bulges upward in the region adjacent to the foramen magnum.

Pleural Space - Space between the lungs and the membranes that surrounds the lungs.

Pseudotumor cerebri (PTC) - another name for IIH; so named because the symptoms mimic the presence of a tumor

Sagittal - A plane or section that divides a structure into right and left portions.

Scoliosis - A congenital abnormal lateral curvature of the spine.

Shunt - a surgically implanted tube used to divert, or drain, CSF

Sleep apnea - See Apnea

Spasticity - Stiffness or position that is difficult to release.

Spina Bifida - The failure of the spine to close properly during the first month of pregnancy. In severe cases, the spinal cord protrudes through the back and may be covered by skin or a thin membrane.

Spinal Stenosis - Abnormal narrowing of the spinal canal. May be congenital, or acquired through injury. Surgery (including a laminectomy) is usually required to widen the canal and thereby reduce pressure on the spinal cord.

Stenosis - the narrowing or blockage of a passage

Syringomyelia - often referred to as SM, is a chronic disorder involving the spinal cord. For reasons that are only now being understood, cerebrospinal fluid enters the spinal cord, forming a cavity known as a syrinx. (It is also termed in reference to other words such as cyst, hydromyelia or syringohydromyelia)

Syrinx - fluid filled cyst in the spinal cord

Suboccipital Craniectomy - exposes the temporal bone for drilling for the translabyrinthine approach. It exposes the sigmoid sinus and the dura medial to it for the retrosigmoid approach

Tachycardia - rapid heart beat

Tethered Cord - A defect in the fusion of the spinal processes and laminas seen in spinal bifida occulata. Sometimes the spinal cord is trapped at the level of the defect and may produce neurological dysfunction. (Tethered) Surgical correction is required.

Tonsillar Herniation - displacement of the cerebellar tonsils out of the skull; usually measured in mm below the bottom of the skull.

Valsalva - a maneuver consistent with straining, a Valsalva headache is one brought on by straining

Ventriculo-Peritoneal Shunt - A shunt or tube inserted into the ventricles of the brain attached to tubing which is placed into the abdominal or peritoneal cavity to drain excess spinal fluid from the brain.

Ventriculosubarachnoid Shunt - A shunt or tube placed in the space occupied by the cerebral spinal fluid (SPF).

Weakness - Inability to grasp or transfer an object.