Polysomnographic respiratory findings in patients with Arnold-Chiari type I malformation and basilar invagination, with or without syringomyelia: preliminary report of a series of cases

Abstract

Patients with craniocervical disorders (CCD) show a wide variety of symptoms and signs suggesting cerebellar and/or high cervical lesion. The anatomic localization of respiratory centers and their possible injury may explain the presence of respiratory disturbances in these diseases. The aim of this preliminary study was to evaluate the polysomnographic findings in a group of patients with CCD, most of them with Arnold-Chiari malformation type I, since sleep apnea has been referred to in isolated cases in the literature. Eleven patients (seven females and four males) with CCD diagnosed by magnetic resonance imaging referred from the neurosurgery unit were submitted to clinical history, physical examination with sleep questionnaires, and scored on the Epworth Sleepiness Scale. Full night polysomnography was performed in an Oxford SAC system where EEG, electro-oculography, electrocardiography, chin and leg electromyography, chest and abdominal efforts, airflow, and oximetry were recorded continuously. Nine patients presented with Arnold-Chiari type I malformation, of whom six showed associated syringomyelia. The other two had basilar invagination. Ninety percent of these patients complained of sleep problems (snoring, choking, and witnessed apneas) and 72% presented hypersomnolence (ESS >9). The polysomnographic findings showed sleep fragmentation in 81% of the patients and a reduction of rapid eye movement sleep in 63%. The apnea/hypopnea index was above 5 in 72%, with a predominance of central apnea. Patients with craniocervical disorders present a higher probability of displaying sleep respiratory disturbances. Their sleep complaints should be assessed and patients should be submitted to an overnight sleep recording in order to identify sleep apnea.

Arnold-Chiari malformation type I and sleep-disordered breathing: An uncommon manifestation of an important pediatric problem

“…Several questionnaires with good validity exist and can be used in a primary care setting and completed by parents while waiting to see the primary care provider. Practitioners should remember that patients with craniocervical disorders present a higher probability of displaying sleepdisordered breathing (Botelho et al, 2000). Practitioners should pay close attention to complaints of sleep disturbances and refer patients to pediatric sleep centers to identify specific problems.…”

“…The types of sleep disorders are identified as central apnea, hypoventilation, and hypoxia. These ventilatory patterns are thought to be caused by a dysfunction in the medullary centers of respiratory control or by cranial nerve dysfunction involving either the vocal cords or bulbar muscles, which mediate airway patency (Botelho et al, 2000). Keefover, Sam, Bodensteiner, and Nicholson (1995) described a 14-year-old adolescent who came to his primary care practitioner with the complaint of excessive daytime somnolence.…”

“…In some cases it may take 6 months to 1 year before improvement is seen (Dure et al, 1989;Shiihara et al, 1995). Botelho et al (2000) demonstrated that patients with craniocervical disorders have a higher probability of sleep disturbances and should have multichannel pneumogram sleep studies performed. The patients studied were diagnosed with Arnold-Chiari type I by MRI; apnea/hypopnea was present in 72% of the cases.…”

“…An MRI revealed Arnold-Chiari type I, and the child underwent suboccipital craniectomy with C1 laminectomy and duraplasty. With MRI, Arnold-Chiari type I can be detected at an earlier age, thus preventing the continuation of the condition into adulthood when individuals are more prone to sudden death resulting from the continuation of their undetected cerebellar and cranial nerve lesions (Botelho et al, 2000). The following is a case presentation of a healthy, asymptomatic 47-month-old child whose history of sleep-disordered breathing led to further evaluation and the prompt diagnosis of Arnold-Chiari malformation type I.…”

“…Cases of sudden death in asymptomatic children who at the time of autopsy were diagnosed with ArnoldChiari type I warrant greater attention to sleep/respiratory manifestations (Botelho, Bittencourt, Rotta, & Tufik, 2000;Martinot et al, 1993). In 1992, Nickerson called for "more widespread recognition of control of breathing problems in patients with Arnold-Chiari malformation" (p. 271).…”