E1666. Prevalence of MRI Findings Supporting Sjogren's Syndrome in Patients With Neuromyelitis Optica
  1. Farshid Taghizadeh; Oregon Health and Science University
  2. Bronwyn Hamilton; Oregon Health and Science University
Salivary glands inflammation and Sjogren’s syndrome have been reported with increased frequency in patients with neuromyelitis optica (NMO). White matter abnormalities suspicious for demyelinating etiology are also more frequent in patients with primary Sjogren’s syndrome. We hypothesized that the prevalence of imaging findings suggesting Sjogren’s syndrome on MRI is higher in patients with NMO compared to the general population, and that these findings may be incidentally seen on MRI of the spine or brain obtained for NMO diagnosis or surveillance.

Materials and Methods:
We did an electronic search of our institutional imaging database from 2010 to 2020 using the keywords “neuromyelitis optica” and “NMO”. An experienced head & neck radiologist and a medical student jointly evaluated all MRI studies for signs of parotid, submandibular, sublingual, and/or lacrimal gland involvement concerning for Sjogren’s syndrome, specifically micronodularity and/or multiple cysts +/- fatty glandular involution involving the salivary tissue in more than one location. Imaging reports also reviewed for any discussion of parotid abnormality. Reviewers were blinded to all clinical data. Cases were scored negative if no findings of Sjogren’s were found and “definite” or “equivocal” for positive cases, based on radiologist confidence. We then reviewed electronic health records to identify patients with clinically established NMO and/or Sjogren’s syndrome, and also rule out Sjogren’s-mimicking diagnoses such as HIV infection, recurrent parotitis, and sarcoidosis.

Our search resulted in 58 patients with MRI studies of the brain and/or spinal cord with indication for NMO or NMO vs. Multiple Sclerosis (MS). Patient population included 17 men (29%) and 41 women (71%) with the age range of 9 to 83 years old. 32/58 (55%) of patients had a clinical diagnosis of NMO and the rest had an indeterminate diagnosis (suspicious for NMO vs. MS). 2/58 (3.4%) patients had clinical Sjogren’s, both with established NMO, and only one radiology report documenting the abnormal parotid glands findings. None were found to have Sjogren’s-mimicking conditions. A total of 7/58 (12.1%) had definite parotid gland abnormalities characteristic of Sjogren’s syndrome. This number increased to a total of 12/58 patients (20.7%) suspicious for Sjogren’s syndrome when equivocal imaging findings were included.

The prevalence of parotid gland imaging abnormalities suspicious for Sjogren’s syndrome on MRI is estimated at 12.1- 20.7%, depending on radiologist confidence. This prevalence far exceeds that of Sjogren’s syndrome in the general population (0.02-0.1%), and confirms a clinically reported correlation between NMO and Sjogren’s syndrome. Reporting potential Sjogren’s in the context of NMO may be important since these patients carry a lifetime risk for lymphoma, and appropriate surveillance may be indicated.