Patients with type I CM do not show any symptoms. Adolescents and adults may develop symptoms of CM later in their life. Patients with CM often complain of neck pain or numbness. There are abnormal feelings in the extremities, muscle weakness and balance troubles. There are altered vision profiles, buzzing in the ears, vomiting, nausea, trouble in swallowing food, and hearing loss. Worsening of the conditions of this malformation leads to insomnia, sleep apnea, persistent headache and depression [3]. Patients may have difficulty in hand coordination and the fine motor skills are also affected.

Children and infants may show symptoms such as difficulty in swallowing and excessive drooling, weakness in arms, breathing problems and developmental delays. Parents are therefore advised to document the symptoms, and convey them to the pediatrician for early diagnosis.

Adult patients with type 1 CM, may initially present with benign paroxysmal vertigo and could be confused as a trivial benign positional vertigo [4]. Patients in the mid age may present with shortness of breath as an inaugural sign due to alveolar hypoventilation [5].

• Weakness

  Central cord symptoms such as hand weakness, sensory loss, and, in severe cases, paralysis may occur. [physio-pedia.com]

  Symptoms of Arnold-Chiari Malformation Decreased strength and/or sensation in the arms and legs Balance and coordination problems Neck stiffness or pain Headache Dizziness Rapid eye movement Poor feeding and swallowing Weak cry or speech difficulties [neurosurgerycnj.com]

  We report a rare case of acute respiratory failure in a previously asymptomatic patient showing clinical signs of inferior cranial nerve palsy together with weakness and muscular atrophy of the upper limbs. [ncbi.nlm.nih.gov]

  Children and infants may show symptoms such as difficulty in swallowing and excessive drooling, weakness in arms, breathing problems and developmental delays. [symptoma.com]

• Developmental Delay

  It is typically brought to light after a child begins exhibiting developmental delays and the parent seeks medical care. [neurosurgerycnj.com]

  Developmental delays may require further medical follow up for underlying problems. During the examination, a measurement of the circumference of the child's head is taken and compared to a scale that can identify normal and abnormal ranges. [urmc.rochester.edu]

  Developmental delays may require further medical follow up for underlying problems. During the examination, a measurement of the circumference of the child’s head is taken and compared to a scale that can identify normal and abnormal ranges. [columbianeurosurgery.org]

• Epilepsy

  (Courtesy Stephanie Barone) Six-year-old Allie Barone had been suffering from severe headaches for a few years — and since her family has a history of epilepsy and migraines, her mother, Stephanie, decided it was finally time to see a specialist. [foxnews.com]

  My condition has also led to epilepsy. [web.archive.org]

  Polymicrogyria (small gyri) and pachygyria (thick gyria) are other consequences of migrational defects with drug-resistant epilepsy being a common feature. [hawaii.edu]

  Grosso S, Scattolini R, Paolo G, Di Bartolo RM, Morgese G, Balestri P (2001) Association of Chiari I malformation, mental retardation, speech delay and epilepsy: a specific disorder? Neurosurgery 49:1099–1104 PubMed Google Scholar 38. [doi.org]

• Impaired Balance

  Dizziness/vertigo – often worsened by extension of the neck Vague pains throughout the body Impaired balance Clumsiness Chronic nausea Foggy thinking, poor memory and concentration Frequent or urgent urination Irritable bowel syndrome Auditory Symptoms [web.archive.org]

  In the type of surgery undertaken for CM these risks include: stroke or bleeding paralysis of the limbs meningitis or other infection impaired speech memory loss or problems with thinking swallowing impairment balance problems fits or seizures, and a [hypermobility.org]

• Cough

  We describe two young women affected with syncopal episodes and occipital headache exacerbated by cough, sneezing, rising, or effort. MRI revealed in both patients type I Arnold-Chiari malformation. [ncbi.nlm.nih.gov]

  Pascual J, Iglesias F, Oterino A, et al.: Cough, exertional, and sexual headaches: an analysis of 72 benign and symptomatic cases. Neurology 1996, 46 :1520–1524. PubMed Google Scholar 9. Pascual J: Primary cough headache. [doi.org]

  Characteristically, but not always, the pain may worsen with neck movement, coughing, or straining movements. Associated neck pain is a frequent complaint. [mhni.com]

• Stridor

  In 2 of these patients only stridor was seen, in 4 stridor with attacks of apnoea, in 2 attacks of apnoea with dysphagia, and in 4 children stridor, attacks of apnoea and dysphagia. [thieme-connect.com]

  We studied respiratory patterns and transcutaneous gas pressures in two infants with Arnold-Chiari type II malformation referred to us due to repeated episodes of stridor and cyanosis. [ncbi.nlm.nih.gov]

  The relationship of apnoea and stridor in spina bifida to other unexplained infant deaths. Dev Med Child Neurol 1974;16:107-116. Worley G, Erwin CW, Schuster JM, Park Y, Boyko OB, Griebel ML, et al. [csfinfo.org]

  In babies, the most common symptoms are a weak or absent cry, breathing difficulties, including stridor, arching of the neck, failure to thrive and feeding or swallowing difficulties. [physio-pedia.com]

• Hoarseness

  Milhorat at that conference discussed that the patients that presented with both EDS and CM1 appeared to have more symptoms relating to anterior brainstem dysfunction including nausea, dysphagia, hoarseness, sleep apnea, difficulty swallowing, dysautonomia [web.archive.org]

  […] include: headache (especially after sneezing, coughing, or straining) balance problems neck pain dizziness vision problems poor hand coordination numbness and tingling of the hands and feet change in bladder (pee) or bowel (poop) habits trouble swallowing hoarseness [kidshealth.org]

  […] balance) Poor hand coordination (fine motor skills) Numbness and tingling of the hands and feet Dizziness Difficulty swallowing, sometimes accompanied by gagging, choking and vomiting Vision problems (blurred or double vision) Speech problems, such as hoarseness [mayoclinic.com]

  Other Symptoms Chiari malformation symptoms can also include: Hoarseness Difficulty swallowing Rapid, side-to-side eye movements (nystagmus) Muscle weakness, lack of balance or abnormal reflexes Nerve problems, including paralysis How is a Chiari malformation [hopkinsmedicine.org]

  Another common complaint linked with Arnold-Chiari malformations is hoarseness. People with Arnold-Chiari malformations may have visual problems, including blurred vision, double vision, or blind spots. There may be bobbing of the eyes. [encyclopedia.com]

• Aspiration

  In our patient recurrent aspirations with consequent inhalation pneumonia occurred. The most important mechanism of recurrent aspiration pneumonia was dysphagia[ 14 ]. [mrmjournal.biomedcentral.com]

  Aspiration from bilateral abductor vocal cord paralysis or central neural dysfunction, or both. Respiratory distress. Episodes of apnoea. Weak cry. Scoliosis. Quadriparesis. Opisthotonic posture. Presentation in childhood or adolescence Syncope. [patient.info]

  "He wasn't a big enough man to begin to go down the road of meeting me on an adult basis, so in a way it was very easy to cut off those emotional hopes and aspirations. [telegraph.co.uk]

  Foreign Body Aspiration (MS3) - Edward W. Fong, MD 7. Pulmonary Hemosiderosis (R) - Scott J. Sheets, DO 8. Pulmonary Vascular Anomalies (R) - Jason H. Brown 9. Bronchogenic Cysts and Cystic Adenomatoid Malformation (R) - Scott J. Sheets, DO 10. [hawaii.edu]

• Vomiting

  However, there may be symptoms such as headache, dizziness, vomiting and nausea. Medical and surgical options are available for the treatment of this disorder. [symptoma.com]

  Other symptoms include neck, arm, and leg pain, numbness, loss of temperature sensation, unsteadiness, double vision, slurred speech, trouble swallowing, vomiting and tinnitus (ringing in the ears). [web.archive.org]

  Headache, vomiting, visual disturbances, diplopia; mental dullness, lack of coordination, paralysis of extremities, cerebellar ataxia, and sensory disorders Aetiology unknown. [whonamedit.com]

  […] made worse by coughing, sneezing, or straining Neck pain Balance problems Muscle weakness Numbness or other abnormal feeing in your arms or legs Dizziness Vision problems Difficulty swallowing Ringing or buzzing in your ears (tinnitus) Hearing loss Vomiting [barrowneuro.org]

  Other complaints that may be noted in these patients are nausea and vomiting, dysarthria, intermittent blurred vision, diplopia, and ataxic gait. [dynamicchiropractic.com]

• Dysphagia

  In 2 of these patients only stridor was seen, in 4 stridor with attacks of apnoea, in 2 attacks of apnoea with dysphagia, and in 4 children stridor, attacks of apnoea and dysphagia. [thieme-connect.com]

  The most important mechanism of recurrent aspiration pneumonia was dysphagia[ 14 ]. [mrmjournal.biomedcentral.com]

  Symptoms include hypotonia, apnea with cyanosis, dysphagia, opisthotonus, nystagmus, spasticity, ataxia, and occipital headache. [orpha.net]

  Helpful Definitions Tinnitus = "ringing in the ears" Nystagmus = irregular eye movements Dysphagia = difficulty swallowing Syncope = fainting Atrophy = "wasting away" (usually of muscles) Analgesia = inability to feel pain Dysesthesia = burning sensation [web.archive.org]

  Compression of the hindbrain can cause weakness, paraesthesia, ataxia, cranial nerve palsies, dysphagia, dysphasia, palpitations, syncope, apnoea and sudden death. [patient.info]

• Dysphagia

  In 2 of these patients only stridor was seen, in 4 stridor with attacks of apnoea, in 2 attacks of apnoea with dysphagia, and in 4 children stridor, attacks of apnoea and dysphagia. [thieme-connect.com]

  The most important mechanism of recurrent aspiration pneumonia was dysphagia[ 14 ]. [mrmjournal.biomedcentral.com]

  Symptoms include hypotonia, apnea with cyanosis, dysphagia, opisthotonus, nystagmus, spasticity, ataxia, and occipital headache. [orpha.net]

  Helpful Definitions Tinnitus = "ringing in the ears" Nystagmus = irregular eye movements Dysphagia = difficulty swallowing Syncope = fainting Atrophy = "wasting away" (usually of muscles) Analgesia = inability to feel pain Dysesthesia = burning sensation [web.archive.org]

  Compression of the hindbrain can cause weakness, paraesthesia, ataxia, cranial nerve palsies, dysphagia, dysphasia, palpitations, syncope, apnoea and sudden death. [patient.info]

• Nausea

  However, there may be symptoms such as headache, dizziness, vomiting and nausea. Medical and surgical options are available for the treatment of this disorder. [symptoma.com]

  Arnold-Chiari malformation Pathology Type Hernia Cause(s) Congenital or genetic Symptoms Headaches, ringing in ears, dizziness, nausea, nystagmus, face pain, muscle weakness, impaired gag reflex, sleep apnea, difficulty swallowing, impaired coordination [house.wikia.com]

  Other complaints that may be noted in these patients are nausea and vomiting, dysarthria, intermittent blurred vision, diplopia, and ataxic gait. [dynamicchiropractic.com]

  Symptoms may include headache, neck pain, numbness of the extremities, dysphagia, nausea, and vomiting. Often the severity of the symptoms increases with the severity of the malformation [ 4 ]. Chiari malformation can be congenital or acquired. [doi.org]

• Tongue Atrophy

  The clinical neurological examination findings for these patients include: papilledema (an indicator of hydrocephalus due to blockage of cerebrospinal fluid flow by the Arnold-Chiari malformation), facial weakness, dysphonia, apnea, tongue atrophy, diplopia [dynamicchiropractic.com]

• Blurred Vision

  Other complaints that may be noted in these patients are nausea and vomiting, dysarthria, intermittent blurred vision, diplopia, and ataxic gait. [dynamicchiropractic.com]

  Visual problems such as nystagmus (involuntary eye movements), double or blurred vision may occur. Balance difficulties, vertigo and dizziness also may be present. Some people may have cranial nerve compression. [asap.org]

  The dizziness and headaches may cause blurred vision that leaves you unable to handle sedentary tasks and complete paperwork. Frequent repositioning may be necessary because of your pain and swelling in lower extremities. [disability-benefits-help.org]

• Tinnitus

  Since the age of 35, the patient had experienced headaches, oculomotor symptoms like blurred vision and diplopia, tinnitus and vertigo. [f1000research.com]

  Other symptoms include neck, arm, and leg pain, numbness, loss of temperature sensation, unsteadiness, double vision, slurred speech, trouble swallowing, vomiting and tinnitus (ringing in the ears). [web.archive.org]

  […] include: Headaches, often made worse by coughing, sneezing, or straining Neck pain Balance problems Muscle weakness Numbness or other abnormal feeing in your arms or legs Dizziness Vision problems Difficulty swallowing Ringing or buzzing in your ears (tinnitus [barrowneuro.org]

• Hearing Impairment

  Vertigo, dizziness, ringing in the ears (tinnitus) and bilateral hearing impairment can also develop. [rarediseases.org]

• Neck Pain

  An 18-year-old female patient presented with left dominant neck pain after a motor vehicle collision. Her cervical spine MRI revealed syringomyelia with associated Type I Arnold-Chiari malformation. [ncbi.nlm.nih.gov]

  Conclusions : The results described in the present investigation are first to demonstrate a neuroradiographic difference between neck pain patients with and without a recent history of whiplash trauma. [doi.org]

  The pain may be frontal (as in the forehead area) or in the neck or back of the head area. Characteristically, but not always, the pain may worsen with neck movement, coughing, or straining movements. Associated neck pain is a frequent complaint. [mhni.com]

• Muscle Spasticity

  spasticity, and episodic urinary retention. [dynamicchiropractic.com]

• Shoulder Pain

  Thirty-two months later, he was readmitted with complaints of occipital, neck, and shoulder pain as well as cerebellar ataxia. [doi.org]

  Stool softeners (e.g., Colace, Docusate) and laxatives (e.g., Dulcolax, Senokot, Milk of Magnesia) may be bought over-the-counter. • Ice packs for 20 minutes can help relieve neck and shoulder pain and muscle spasms. [mayfieldchiaricenter.com]

• Headache

  In this unique case report, a 32-year-old, postpartum woman with posturally induced headache from Chiari malformation type I had symptoms occur for the first time during pregnancy. [ncbi.nlm.nih.gov]

  Repeat myelography was unrevealing, but subsequent multilevel epidural blood patches with fibrin glue led to headache resolution. [neurology.org]

• Dizziness

  It isn’t effective for all cases of dizziness or headaches. There are no medications or treatments for the underlying cause of the malformation. You may be prescribed medications for the symptoms, such as dizziness and headaches. [disability-benefits-help.org]

  Symptoms of Arnold-Chiari Malformation Decreased strength and/or sensation in the arms and legs Balance and coordination problems Neck stiffness or pain Headache Dizziness Rapid eye movement Poor feeding and swallowing Weak cry or speech difficulties [neurosurgerycnj.com]

  Arnold-Chiari malformation Pathology Type Hernia Cause(s) Congenital or genetic Symptoms Headaches, ringing in ears, dizziness, nausea, nystagmus, face pain, muscle weakness, impaired gag reflex, sleep apnea, difficulty swallowing, impaired coordination [house.wikia.com]

  The drummer sought medical attention after she started experiencing symptoms including dizziness, insomnia, headaches, tingling/numbness in her hands and a stiff neck. [nme.com]

• Nystagmus

  Oscillopsia and nystagmus began in a woman 2 weeks after an inadvertent lumbar puncture during anesthesia for childbirth. Examination showed horizontal-torsional jerk nystagmus in all positions of gaze. [ncbi.nlm.nih.gov]

  Much stronger downbeating nystagmus seen on eccentric gaze, in patient with a prominent Chiari Malformation. There is no rebound nystagmus -- he has a right-beating nystagmus that remains direction fixed on centering. [dizziness-and-balance.com]

• Vertigo

  Clinical manifestations of types I-III include TORTICOLLIS ; opisthotonus; HEADACHE ; VERTIGO ; VOCAL CORD PARALYSIS ; APNEA ; NYSTAGMUS, CONGENITAL ; swallowing difficulties; and ATAXIA. [hon.ch]

  Adult patients with type 1 CM, may initially present with benign paroxysmal vertigo and could be confused as a trivial benign positional vertigo. [symptoma.com]

  Clinical manifestations of types I-III include TORTICOLLIS; opisthotonus; HEADACHE; VERTIGO; VOCAL CORD PARALYSIS; APNEA; NYSTAGMUS, CONGENITAL; swallowing difficulties; and ATAXIA. [termsciences.fr]

  They may experience vertigo, difficulties with balancing, and dizziness. [disabled-world.com]

• Ataxia

  We highlighted a case of Chiari type I malformation, who presented with posterolateral ataxia associated with significant vitamin B(12) deficiency. [ncbi.nlm.nih.gov]

  Thirty-two months later, he was readmitted with complaints of occipital, neck, and shoulder pain as well as cerebellar ataxia. [doi.org]

  Clinical manifestations of types I-III include TORTICOLLIS ; opisthotonus; HEADACHE ; VERTIGO ; VOCAL CORD PARALYSIS ; APNEA ; NYSTAGMUS, CONGENITAL ; swallowing difficulties; and ATAXIA. [hon.ch]

  Symptoms include hypotonia, apnea with cyanosis, dysphagia, opisthotonus, nystagmus, spasticity, ataxia, and occipital headache. [orpha.net]

Though there are no specific symptoms associated with this malformation, it is often discovered only when complications arise.

Diagnostic tests

• X-ray: Though X-ray of the head and neck cannot reveal the CM, it can help to identify the abnormalities associated with the bones related to CM.
• Computed tomography (CT): This scan produces a 2-dimensional picture of the bone and the vascular irregularities, along with cyst formation or brain damage.
• Magnetic resonance imaging (MRI): MRI will elucidate findings of tonsillar herniation of at least 5mm, overcrowding of structures by the foramen magnum and the underdevelopment of the posterior cranial fossa which clinches the definitive imaging diagnosis of type I CM [6]. A pre-surgical MRI evaluation of the cerebrospinal fluid flow in the foramen magnum may determine the degree of tonsillar herniation which correlates directly to the success rate of the operation [7].

If this disease does not show any symptoms and interfere with the daily activities, treatment is not necessary. Symptomatic treatment is quite common in the absence of the correct diagnosis, for example, if pain persists; analgesics are advised to manage the symptoms. However, if there are multiple symptoms that affect the patient on the day-to-day basis, surgery is the only treatment modality that can cease the progression of the disease. The goal of surgery in Chiari malformation is two-fold:

1. Relief of the pressure on the brain and the spinal cord.
2. Restoring the fluid circulation in and around the area.

Some of the common surgical procedures performed in patients with CM are as follows:

• Posterior fossa decompression surgery: In this surgery, there is a removal of the portion of the bottom of the skull or the spinal cord to correct the altered bony structures. In the procedure, the dura is also opened and widened, creating an additional space for the fluid to circulate. Foramen magnum decompression procedures resolves primary signs and help resolve complications like syringomyelia [8].
• Electrocautery: High frequency electrical current helps to shrink the lower part of the cerebellum making the space needed.
• Spinal laminectomy: In this procedure, the part of the bony roof of the spinal canal is removed, thus increasing the size and reducing the pressure on the spinal cord.

Surgery of the malformation has shown to reduce the symptoms significantly, prolonging the periods of remission.

Type I CM is generally asymptomatic. In complicated cases, surgery can help to reduce the symptoms associated with the malformation.

Complications

There are cases documented where CM becomes progressive, leading to serious complications. The complications associated with the disorder are as follows:

• Hydrocephalus: This is a condition in which there is an excess accumulation of cerebrospinal fluid in the brain, thus requiring the placement of the shunt to drain this excess fluid.
• Spina bifida: This is the condition in which the spinal cord or its covering is not fully developed, and forms a manifestation of ACM. Serious complications such as paralysis is common in such patients.
• Syringomyelia: There can be an appearance of the cyst or cavity which is formed within the spinal cord. This is referred to as syringomyelia. The untreated syringomyelia may complicate with neuropathic arthropathy which are more marked in the elbows [2].
• Tethered cord syndrome: Sometimes the spinal cord gets stretched causing severe nerve and muscle damage to the lower part of the body.

The causes of Chiari malformations are categorized into primary and secondary. Primary CM can occur with the structural defects in the brain or the spinal cord during the fetal development either due to lack of the proper nutrient in the maternal diet (during development) or genetic mutations. Hence, this is called primary or congenital CM. Primary CM is more common than the secondary CM. When the CM occurs later in life, it is called secondary or acquired CM. This can happen if there is an excessive drainage of the spinal fluid from the lumbar or thoracic areas of the spine which can occur either because of injury or infection.

Depending on the severity of the CM and the parts of the brain affected, Chiari malformation can be divided into type I, type II, type III and type IV.

• In type I CM, there is an extension of the lower parts of cerebellum into the foramen magnum and may not cause many symptoms. It is the common type, often noticed in adolescence.
• Type II is also referred to as classic CM. This involves the extension of both the cerebellar and brain tissues. Arnold Chiari malformation is often used to specifically refer to type II malformation.
• The most serious type of CM is type III. In this, the brainstem and the cerebellum protrude through the foramen magnum into the spinal cord. This type of ACM causes the most severe neurological defects.
• In type IV CM, there is an incomplete or underdeveloped cerebellum.
• In recent times, type 0 CM is also included in the classification. In Type 0, though there is no protrusion of the cerebellum, the patient may experience symptoms that mimic that of CM.

Primary type I CM is also attributed to the linkages to chromosomes 9 and 15. It is suggested that the disorder occurs in the para-axial mesoderm, resulting in the formation of the smaller posterior fossa. There are other theories regarding the cause of Arnold Chiari Malformation, one of the interesting one is called “CSF loss theory”. According to this hypothesis, there is an escape of the fluid in the myelomeningocele which results in inadequate stimuli of the mesenchymal condensation at the base of the skull.

Earlier it was believed that CM occurred one in every 1,000 births. With the development of the diagnostic imaging in the past few decades, the occurrence is found to be more common. Today CM may reach up to 5 cases per 1000 births with female predominance over male subjects [1]. Since, there are cases where the child born with ACM does not show symptoms until they reach adolescence, the exact epidemiological profile of the disease is still not known. The disorder is more common among women than men. Type II malformations are more prevalent among the different types of CM.

The pathophysiological complications that lead to the consequences of this malformation can be due to the following:

1. Compression of the medulla, upper spinal cord and/or cerebellum. The complications associated with the medulla and the cord can result into myelopathy and nuclear dysfunction. Ataxia and nystagmus or loss of equilibrium is associated with the compression of the cerebellum.
2. Disruption of the flow of the CSF through the foramen magnum causes the symptoms of pain which are associated with CM.

There are no preventive measures to combat Arnold Chiari malformation; genetic counseling can prove beneficial to the parents of the child to determine the risk in future children.

Chiari malformations (CM) are a group of congenital abnormalities that affect the hindbrain. In the CMs, the part of the cerebellum is located below the foramen magnum in the brain, and may develop when the bony space is smaller than the normal, causing the brainstem to be pushed downward to the foramen magnum. The pressure that ensues due to this structural deformity on the cerebellum and brainstem affects the functions, blocking the flow of cerebrospinal fluid (CSF).

Patients with Arnold Chiari malformation (ACM) generally do not show any symptoms, therefor the condition is often diagnosed during the course of diagnosis for another disorder. However, there may be symptoms such as headache, dizziness, vomiting and nausea. Medical and surgical options are available for the treatment of this disorder.

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2. Yanik B; Tuncer S; Seçkin B. Neuropathic arthropathy caused by Arnold-Chiari malformation with syringomyelia.Rheumatol Int. 2004; 24(4):238-41 (ISSN: 0172-8172)
3. Tsara V; Serasli E; Kimiskidis V; Papagianopoulos S; Katsaridis V; Fylaktakis M; Christaki P; Kazis A. Acute respiratory failure and sleep-disordered breathing in Arnold-Chiari malformation.Clin Neurol Neurosurg. 2005; 107(6):521-4 (ISSN: 0303-8467)
4. Unal M; Bagdatoglu C. Arnold-Chiari type I malformation presenting as benign paroxysmal positional vertigo in an adult patient. J Laryngol Otol. 2007; 121(3):296-8 (ISSN: 1748-5460)
5. Chaouch N; Meraï S; Cheikh Rouhou S; Ben Romdhane K; Ben Mrad S; Besbes M; Tritar F. [Acute respiratory failure as the sol inaugural sign of Arnold-Chiari malformation. Two cases] Rev Pneumol Clin. 2007; 63(5 Pt 1):319-22 (ISSN: 0761-8417)
6. Khan AA; Bhatti SN; Khan G; Ahmed E; Aurangzeb A; Ali A; Khan A; Afzal S. Clinical and radiological findings in Arnold Chiari malformation. J Ayub Med Coll Abbottabad. 2010; 22(2):75-8 (ISSN: 1025-9589)
7. McGirt MJ, Nimjee SM, Fuchs HE, George TM. Relationship of cine phase-contrast magnetic resonance imaging with outcome after decompression for Chiari I malformations. Neurosurgery. Jul 2006;59(1):140-6; discussion 140-6.
8. Takigami I; Miyamoto K; Kodama H; Hosoe H; Tanimoto S; Shimizu K. Foramen magnum decompression for the treatment of Arnold Chiari malformation type I with associated syringomyelia in an elderly patient. Spinal Cord. 2005; 43(4):249-51 (ISSN: 1362-4393)