Evaluating the Level of the Cerebellar Tonsils of Adolescents with Idiopathic Scoliosis in Upright verses the Recumbent Positions

Marc J. Lamantia , Gary Deutchman, Scott Bender


Study Design. Magnetic resonance imaging (MRI) performed with both a Fonar upright Scanner and a recumbent type scanner, to compare quantitatively the position of the cerebellar tonsils in adolescents patients with Idiopathic Scoliosis.

Objectives.  The study objectives are to identify the differences between upright and recumbent MRI when diagnosing Arnold Chiari Malformation in patients with Idiopathic Scoliosis. 

Summary of Background Data.  Arnold Chiari l Malformation has been reported in patients with Adolescent Idiopathic Scoliosis to be as high as 20 percent when evaluated in a recumbent scanner. No studies have been done to determine if the upright position is more sensitive to diagnosis the condition. 

Methods.  Sagittal MRI images of the hindbrand are to be compared with each participant in the upright and recumbent postures.  Measurements of the Basion-Opisthion reference line (BO line) as described by Cheng et al 2003, will be blindly measured by two independent participating radiologists.  Statistical analysis will be performed to determine if a significant difference is noted in the magnitude or incidence of ACM.

Significance of Study. Adolescent Idiopathic Scoliosis (AIS) may result from occult ACM which is currently being undiagnosed due to the recumbent positioning on MRI Scanning. 

Patients and Methods.  This Pilot Study includes 30 adolescents from the ages from 12 to 14 years, with 15 healthy normal controls randomly recruited from patients seeking non-surgical care for previously diagnosed AIS.  Exclusion criteria for the control group will include anyone who has a family member with known ACM.  Patients with head Injuries or a previous diagnosis of ACM will also be excluded from all the study.  Patients are to be assigned a severity score for their Cobb Angle measurement. A Cobb Angles of 0-9 degrees (controls)=0.  Cobb angles from 9-20 =1, from 21-40=2, from 41-55=3, and from 55 and above=4. 

IRB approval will be obtained prior to the beginning of the study and can be organized through New York Chiropractic College.

The MRI studies performed in random order using a 1.5 T MRI unit in both the recumbent and Upright Conditions. 

Cobb measurements obtained from the Upright Scoliscan to reduce the need for exposure to Ionizing radiation. 

Images will be chosen when the Cerebellar aqueduct in adequately visualized (Sylvian Aqueduct) with reference to the basion and opitsthion.

Measurements made by two independent investigators and the intraclass correlation coefficient should be reported. 

Statistical Analysis. t Tests, Spearman Rank Correlations can be used to tests the statistical relationship between the position of the cerebellar tonsils and the scoliosis severity score (Cheng 2003), and the relationship between the cerebellar tonsilar tip and the scoliosis severity score.  Statistical significance is considered to be P<0.05.

Plan.  Publish paper in peer reviewed journal. Follow up studies should include a larger sample, and functional measurements of CSF flow, and the effects of non-surgical corrective interventions on the natural history of AIS. 

Cost of the Proposed Study:

90 hindbrain MRI Scans x $800ea = $72000.

45 Scoliscan MRI for Cobb measurements @200per = $9000

90 hours x 2 Neuroradiologist investigators (180 hrs x $200/hr)- $36000

Research Assistants for Statistical analyses and gathering of data= $15000

Total = approximately $135,000