Retro-odontoid Pseudotumor Mimicking Acute Stroke Symptoms—An Unusual Case Report
Manmeet Kaur1, Nithisha Thatikonda1, Aabishkar Bhattarai1, Muhammad Memon2, Jorge Rodriguez-Fernandez2
1Department of Neurology, UTMB, Galveston TX, 2UTMB, Galveston TX
Objective:
To learn about atypical presentation of retro-odontoid pseudotumors as stroke mimics. 
Background:
Very few cases have been reported in literature about non-rheumatoid retro-odontoid pseudotumors presenting as sudden onset acute stroke like symptoms in emergency department. 
Design/Methods:
NA
Results:

Retro-odontoid pseudotumor is a non-neoplastic, soft tissue thickening posteriorly to the dens of C2 vertebra generally causing atlantoaxial instability in patients with rheumatoid arthritis. There have been reports of non-rheumatoid retro-odontoid pseudotumors associated with severe degenerative spine disease resulting in sub-axial ankylosis, atlantooccipital assimilation, ossification of the anterior and posterior longitudinal ligament, and diffuse idiopathic skeletal hyperostosis. We present a case of non-rheumatoid retro-odontoid pseudotumor which presented with symptoms mimicking acute stroke. 65-year-old male with history of HTN, HLD, non-obstructive CAD, NSTEMI, bilateral carotid stenosis status post right carotid stent and transcarotid artery revascularization procedure, squamous cell carcinoma of tonsil and neck status post head and neck surgery, chemotherapy with Erbitux and radiation(in remission), scoliosis, and chronic neck and lower back pain who presented with right sided weakness, numbness and slurred speech for 3 hours, patient received thrombolytic therapy and was transferred to neuro-ICU. During his hospital stay, patient had fluctuating course of right sided weakness. Imaging including CT and MRI were negative for stroke but did reveal retro-odontoid pannus formation with mild to moderate mass effect on the brain stem. Patient underwent fixation of occiput to C5 with C3-C4 laminectomy with improvement in symptoms. NRROPs may rarely present with acute neurological deficits mimicking stroke-like presentation and therefore it is important to know atypical presentation of these pseudo-tumors and to consider as a stroke mimic. 

Conclusions:
Although there may be high suspicion of stroke given strong risk factors but we need to keep in mind structural abnormalities that may explain symptoms in patients with negative imaging and can consider this presentation as a possible stroke mimic. 
10.1212/WNL.0000000000204629