The Chiari Institute of the Neuroscience Institute


The Chiari Institute is the world's first comprehensive, multidisciplinary center for the management of patients suffering from Chiari malformation, a rare structural condition that affects the cerebellum; syringomyelia, a chronic disease of the spinal cord; and related disorders.

Founded by Dr. Thomas H. Milhorat, former chairman of the departments of neurosurgery at North Shore University Hospital and Long Island Jewish Medical Center, the Chiari Institute represents the fruition of his extensive effort to establish an institution dedicated to the treatment of these often misdiagnosed conditions.

The institute is named in honor of Professor Hans Chiari, an Austrian pathologist who first described abnormalities of the brain at the junction of the skull and spine more than a century ago. Physician members of the Chiari Institute include neurosurgeons, neurologists and neuroradiologists, as well as specialists in pain management, cardiology, respiratory physiology, neuro-ophthalmology, neuro-otology, general medicine and pediatrics.

Advancing Chiari Malformation Diagnosis and Treatment
The diagnosis and treatment of Chiari malformation (CM) and related disorders has yet to be standardized. Controversies have arisen in the medical community regarding the diversity and variability of presenting symptoms, as well as the specific radiological criteria for diagnosis. Patients with CM1, for example, frequently experience chronic fatigue or fibromyalgia-like symptoms, yet only a small percentage of patients with these symptoms actually have CM1. On the other hand, a significant number of patients with radiographically confirmed CM1 are misdiagnosed for years as suffering from conditions such as multiple sclerosis, migraine and psychiatric disorders. A multidisciplinary team of physicians with special expertise in the diagnosis and treatment of CM is required to resolve such issues.

The need for the Chiari Institute has been patient-driven. Since 1991, Dr. Milhorat and his team have amassed the largest specialized experience of any surgical group in the world. In 2003 alone, the team performed 292 surgical procedures at North Shore University Hospital, more than half of which were referred for re-operation because of failed Chiari surgery elsewhere. Approximately 75 percent of the institute’s patients come from outside the New York metropolitan area and represent all 50 states, as well as 40 foreign countries. The Chiari Institute has performed over 5,000 surgeries at North Shore University Hospital since its founding in 2003.

Could It Be Chiari Malformation?
If you are suspected of having Chiari malformation, proper diagnosis begins with a detailed clinical questionnaire. A team of nurse practitioners supervises the data entry, scheduling of tests and physician consultations. Our secretarial department assists with housing requests.

Outpatient activities are conducted with a multidisciplinary approach. The detailed diagnostic workup includes six MRIs, C MRIs, dynamic X-rays, 3D CTs, high-definition imaging and morphometrics. These are followed by a screening evaluation by a nurse practitioner with clinical screens for Ehlers-Danlos Syndrome and tethered cord syndrome. The next step is an appointment with a neurologist. The diagnostic process culminates with a neurosurgical visit. The final product is a report of at least 11 pages.

The goals of the diagnostic workup are to:

  • Establish the correct diagnosis
  • Educate the patient and answer their questions
  • Provide a list of management options
  • Discuss the preferred operative technique if surgery is required

The development of a multidisciplinary approach to address the medical and surgical needs of patients combined with an active research program has elevated the Chiari Institute to the highest level of international recognition.

Your Treatment Options
The decision to have surgery for Chiari malformation requires a detailed consultation between you and your physician. The most important function of the Chiari Institute team is to assess and analyze your specific condition.

Since our inception, we have developed a patient-specific surgical procedure depending upon the underlying cause of the condition. Each step of the operation is tailored to your unique anatomical and physiological findings. The reason for or against surgery depends upon the potential risk versus benefits. Surgical intervention is discussed so that you are empowered to make an informed, personal decision. The requirements for successful Chiari surgery are:

  • Optimal decompression of nerve tissue
  • Reconstruction of normal-sized cerebrospinal fluid (CSF) spaces behind the cerebellum called cisterna magna
  • Restoration of normal CSF flow between the cranial and spinal compartments

Surgeries Performed at the Chiari Institute
The surgeries we perform are diversified and include:

  • Posterior fossa decompression
  • Posterior fossa revision
  • Craniocervical fusion
  • Syringomyelia surgery
  • Hypothalamic hamartoma surgery
  • Numerous minor surgeries, including:
    • Invasive surgical traction
    • Ventriculoperitoneal shunt
    • Anterior cervical discectomy fusion

A surgical approach is greatly enhanced by the use of color Doppler sonography and morphometric measurements.

Specialization Means Expertise
Since Chiari-related surgeries are performed daily at the Chiari Institute, our surgeons benefit from the concept of full immersion. They have been exposed to an endless series of anatomical variants and have faced and solved complex technical problems.

Why choose the Chiari Institute

Comprehensive, Specialized Knowledge

  • Chiari-related surgeries are performed daily at the Chiari Institute.
  • TCI's surgeons have been exposed to an endless series of anatomical variants and have faced and solved complex technical problems.

Groundbreaking Research

  • Chiari Institute physicians were the first to:
    • Find the link between Chiari I malformation and Ehlers-Danlos Syndrome in a subgroup of Chiari patients
    • Discover and investigate the relationship between Ehlers-Danlos Syndrome and functional cranial settling
    • Define the link between tonsillar herniation and occult cord tethering in a subgroup of Chiari patients

World-Renowned Care
The Chiari Institute’s patients have come from all 50 states and from 40 foreign countries.

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