Probable Tolosa-Hunt syndrome with a normal MRI

Background We are reporting a rare case of a 60-year-old woman with a past history of end-stage renal disease and non-Hodgkin lymphoma who presented to our hospital with confusion, unilateral headache, painful ophthalmoplegia and ptosis. The patient was diagnosed clinically with Tolosa-Hunt syndrome (THS). Results THS is a diagnosis of exclusion. Other diseases were ruled out. Magnetic resonance imaging (MRI) of the brain and orbit was negative twice within a week. The patient was treated with corticosteroids with marked improvement of the orbital pain and headache and mild improvement of the cranial nerves palsy. Conclusion Clinical diagnosis of THS could be supported by radiological findings. According to the International Classification of Headache Disorders (ICHD)-3 beta diagnostic criteria, the diagnosis must be confirmed with an abnormal MRI and/or pathological sample. We add to the previous findings of THS with a normal MRI. Although MRI plays a crucial role in differential diagnosis, it should not, nor should the biopsy, be a must for the diagnosis. Limitations of using MRI in some patients are another problem.