Type One Chiari Malformation as a Cause of Central Sleep Apnea and
Hypoventilation in Children
Abstract
Objectives: Chiari type 1 malformation (CM1) may occasionally
lead to central sleep apnea (CSA). We studied, in a large clinical
cohort of pediatric CM1 patients, the effect of CM1 on breathing during
sleep. Methods: This is a retrospective single pediatric
pulmonology center study with a systematic evaluation of pediatric CM1
patients under age 18 with polysomnography (PSG) during 2008-2020.
Children with syndromes were excluded. All patients had undergone head
and spine magnetic resonance imaging. Results: We included 104
children with CM1 with a median age of 7 (interquartile range (IQR)
5-13) years. The median extent of tonsillar descent (TD) was 13 (IQR
10-18) mm. Syringomyelia was present in 19 children (18%). Of all
children, 57 (55%) had normal PSG, 31 (30%) showed periodic breathing
or central apnea index ≥5 h -1, and 16 (15%)
displayed features of compensated central hypoventilation and periods
with end-tidal or transcutaneous carbon dioxide 99 th
percentile level above 50 mmHg. TD had the best predictive value for
central breathing disorders. In a linear model, both age (61%) and TD
(39%) predicted median respiratory rate (R = 0.33, p <
0.001). Conclusions: Although severe CSA is a rare complication
of brainstem compression in pediatric patients with CM1, short
arousal-triggered episodes of periodic breathing and mild compensated
central hypoventilation are common. TD shows the best but still poor
prediction of the presence of a central breathing disorder. This
highlights the use of PSG in patient evaluation. Posterior fossa
decompression surgery effectively treats central breathing disorders.