Bulbar "Red Flag" Symptoms and a 21-Year Diagnostic Delay in Adult Arnold-Chiari Type II Malformation With Tracheoesophageal Fistula and Syringomyelia: A Case Report.

The simultaneous occurrence of Arnold-Chiari Malformation Type II (ACM II), syringomyelia, and an acquired tracheoesophageal fistula (TEF) in a young adult is exceptionally rare and represents a major diagnostic challenge. Arnold-Chiari Malformation II is characterized by the herniation of cerebellar structures through the foramen magnum. It usually presents in infancy in association with myelomeningocele; co-existing TEF and syringomyelia in an adult, as in our patient, is seldom documented. Notably, the present case represents a Chiari II phenotype without spinal dysraphism, lying outside the classic definition that requires an associated myelomeningocele. A 21-year-old male presented with a two-year history of progressive neurological and oropharyngeal symptoms. He also reported nasal regurgitation, cervicogenic vertigo, photophobia, and hoarseness. Neurological examination revealed multidirectional nystagmus, optic atrophy in the right eye, right cerebellar signs, fasciculations, and fundoscopy showed a filled disc and temporal margin blurring in the right eye. MRI of the brain and cervical spine revealed a 10.3 mm herniation of the cerebellar tonsils below the foramen magnum, typical of ACM Type II with syringomyelia. The brain CT scan identified a tracheoesophageal fistula above the carina with a 0.5 cm communication and a diverticulum on the right side of the trachea. Initially, the patient was treated symptomatically with antihistamines, antibiotics, and nasal sprays. The patient was also given multidisciplinary consultation for neurosurgical decompression and underwent posterior fossa decompression surgery, including suboccipital craniectomy and C1 laminectomy, to relieve compression at the foramen magnum and restore cerebrospinal fluid flow. This case underscores an unusual constellation of ACM Type II with extracranial complications and highlights the diagnostic importance of neuroimaging in complex craniospinal presentations.