LAUSR

Chiari malformation type 1 (CM1) is defined as herniation of the cerebellar tonsils from the foramen magnum of more than 5 mm (Tubbs et al. 2007). CM1 is the most common and clinically least severe type of Chiari malformation. Most patients diagnosed with CM1 are asymptomatic and are usually detected incidentally in brain imaging performed for other reasons (Tubbs et al. 2015). Studies show that CM1 is detected in 1% to 3.6% of children (Strahle et al. 2011). The most common symptom of CM1 in both adult and pediatric patients is headache, which is present in approximately 80% of patients. Excepting pain, symptoms including motor and sensory deficits, hand muscular atrophy, lower cranial palsy, cerebellar ataxia, nystagmus, dysphagia, and dysphonia are observed (Ciaramitaro et al. 2019). Psychiatric disorders accompanying CM1 have been mentioned in a few case reports. These cases are generally adult patients diagnosed with anxiety disorders, major depression, panic disorder, and bipolar disorder. In a comprehensive study conducted on adult CM patients, 43.8% of the patients were found to have psychiatric disorders. The most common psychiatric disorders were major depressive disorder and anxiety disorder, with a rate of 18.8% and 12.5%, respectively (Bakim et al. 2013). In a study in which 86 pediatric CM 1 cases were evaluated, at least one psychiatric disorder was found in 47% of these children (Lacy et al. 2018). Here we present a case of CM1 accompanying conversion disorder for the first time in the literature.