Positional dysphagia secondary to a Chiari I malformation.
We describe a previously unreported phenomenon: positional dysphagia secondary to a Chiari I malformation. A 38-year-old woman presented with progressive dysphagia and cough. Flexible endoscopic evaluation of swallowing detected severe pharyngeal dysphagia and aspiration, as well as an intermittent cough reflex with all consistencies in the upright position. Various compensatory strategies were attempted to relieve the aspiration, but only assumption of the supine position was successful. Subsequent magnetic resonance imaging detected a herniation of the cerebellar tonsils to the level of C2 and the presence of a cervical syrinx--findings consistent with a Chiari I malformation. After surgical decompression of the malformation, the patient's symptoms completely resolved.
A Chiari I malformation is a congenital anomaly characterized by a downward herniation of the cerebellar tonsils through the foramen magnum. It often does not manifest until the second or third decade of life. The typical presentation includes headache, dizziness, an unsteady gait, lower cranial nerve signs, a loss of sensation in the upper spine, and upper motor-neuron signs. (1) Dysphagia does occur in patients with a Chiari I malformation, but it is uncommon. (2)
We describe a unique case of positional dysphagia secondary to a Chiari I malformation. To the best of our knowledge, such a finding has not been previously reported in the literature.
A 38-year-old woman with hypertension and iron deficiency anemia presented to an otolaryngologist and a speech-language pathologist with a 3-month history of progressive dysphagia. Initially, she had experienced intermittent dysphagia that resulted in coughing with any type of food or liquid. Later her condition progressed to coughing and choking during every meal. In addition to the dysphagia, she had a 3-year history of chronic cough, for which she had seen multiple physicians, and she had been unsuccessfully treated for gastroesophageal reflux and asthma. She also reported a sensation of pressure within her head during laughing that had occurred occasionally since childhood. Finally, she had also experienced brief and severe headaches with cough for several years, intermittent paresthesias down both arms, and recent mild balance problems.
On examination, the patient exhibited no dysarthria, no ptosis, normal extraocular movements, symmetrical but weak palate elevation, and normal tongue movements. She had full strength, brisk reflexes in all extremities, downgoing toes on plantar reflex testing, normal cerebellar test results, a steady gait, and normal sensation in her back, supraclavicular area, and elsewhere.
Flexible endoscopic evaluation of swallowing (FEES) detected severe pharyngeal dysphagia and aspiration, as well as an intermittent cough reflex with all consistencies in the upright position. Various compensatory strategies--including chin tuck, head lean, and assumption of the supine position--were attempted, but only assumption of the supine position led to cessation of the aspiration.
The patient was able to safely eat and drink while in the supine position. Her severe and unexplained dysphagia prompted us to obtain a magnetic resonance imaging (MRI) scan of the brain and to refer her to the neurology service. The MRI showed herniation of the cerebellar tonsils to the level of C2 and the presence of a cervical syrinx--findings consistent with a Chiari I malformation (figure). She underwent a suboccipital craniectomy and C1-C2 laminectomy without complication. Six days later, her chronic cough had resolved and she had only trace aspiration of thin liquids during FEES. Two weeks postoperatively, her dysphagia had completely resolved.
Dysphagia with a Chiari I malformation is relatively uncommon; the estimated prevalence ranges between 2.5 and 6%. (2,3) There have been reports of dysphagia as the sole presenting symptom of a Chiari I malformation, but they are rare. (4) To the best of our knowledge, positional dysphagia has not been previously described in the literature. In addition, improvement in the supine position of positional dysphagia secondary to any underlying etiology is not commonly encountered.
We present two working hypotheses as to why our patient's swallowing improved while in the supine position:
* One intriguing possibility is that when our patient was upright, crowding of the craniocervical junction by the cerebellar tonsils compressed the medulla and resulted in dysfunction of the glossopharyngeal nerves. When she was supine, the pressure on the medulla was relieved, resulting in improved glossopharyngeal nerve function. This hypothesis is consistent with the rapid resolution of the dysphagia following surgical decompression, suggesting a transient pharyngeal dysfunction.
* A second possibility is that our patient gained a mechanical advantage in the supine position, and food was directed toward her posterior pharynx and away from the larynx, which reduced aspiration. This is a previously documented phenomenon, and this compensatory technique is occasionally used in patients with dysphagia. (5)
Knowledge of the potential association between positional dysphagia and a Chiari malformation is important for clinicians who evaluate patients with unexplained swallowing disorders. In patients who present with unexplained dysphagia, the diagnosis of a Chiari malformation or other cause of lower cranial nerve dysfunction should be considered when an instrumental swallowing evaluation demonstrates resolution of aspiration in the supine position.
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(1.) Milhorat TH, Chou MW, Trinidad EM, et al. Chiari I malformation redefined: Clinical and radiographic findings for 364 symptomatic patients. Neurosurgery 1999;44(5):1005-17.
(2.) Dyste GN, Menezes AH, VanGilder JC. Symptomatic Chiari malformations. An analysis of presentation, management, and long-term outcome. J Neurosurg 1989;71(2):159-68.
(3.) Mohr PD, Strang FA, Sambrook MA, Boddie HG. The clinical and surgical features in 40 patients with primary cerebellar ectopia (adult Chiari malformation). Q ! Med 1977;46(1):85-96.
(4.) Achiron A, Kuritzky A. Dysphagia as the sole manifestation of adult type I Arnold-Chiari malformation. Neurology 1990;40(1):186-7.
(5.) Ha IS, Park SO, An HM, Park IS. The usefulness of supine position on swallowing of liquid diet in neurogenic dysphagia: Comparison with sitting position. J Korean Acad Rehabil Med 2001;25(6): 916-22.
David L. White, MD; Catherine J. Rees, MD; Susan G. Butler, PhD; Stephen B. Tatter, MD, PhD; Lisa W. Markley, MS, CCC-SLP; Michael S. Cartwright, MD
From the Department of Otolaryngology (Dr. White, Dr. Rees, and Dr. Butler), the Department of Neurosurgery (Dr. Tatter), and the Department of Neurology (Dr. Cartwright), Wake Forest University School of Medicine, Winston-Salem, N.C.; and the Audiology and Speech Pathology Service, the Durham VA Medical Center, Durham, N.C. (Ms. Markley).
Corresponding author: Catherine J. Rees, MD, Center for Voice and Swallowing Disorders, Wake Forest University School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157. E-mail: firstname.lastname@example.org