Signs of Tonsillar Herniation in Children
Tonsillar herniation in children most commonly presents with occipital headache worsened by Valsalva maneuver, abnormal oropharyngeal function in children under 3 years, and scoliosis associated with syringohydromyelia in older children. 1
Clinical Presentation by Age Group
Children Under 3 Years
- Abnormal oropharyngeal function is the most common manifestation in this age group, including difficulty swallowing, choking, or feeding difficulties 1
- Respiratory symptoms may be prominent 1
Children Over 3 Years
- Occipital and cervical headaches are characteristic, though isolated occipital headache in children is rare and warrants diagnostic caution 1
- Headache exacerbated by Valsalva maneuver (coughing, sneezing, straining) is highly suggestive 1
- Scoliosis, particularly when associated with syringohydromyelia, is a typical finding 1
Key Clinical Signs to Assess
Neurological Symptoms
- Hyperreflexia in extremities 2
- Dysequilibrium or balance problems 2
- Progressive neck pain and stiffness 2
Associated Findings
- Dorsal brainstem compression manifesting as medullary symptoms 3
- Obliteration of cerebrospinal fluid space between the dorsal brainstem and tonsils on imaging 3
Critical Diagnostic Considerations
MRI of the brain with sagittal T2-weighted sequences of the craniocervical junction is the diagnostic study of choice when tonsillar herniation is suspected 1. Optional phase-contrast CSF flow studies at the craniocervical junction can provide additional information 1.
Imaging Criteria
- Any cerebellar tonsillar descent below the basion-opisthion reference line should be considered abnormal in adolescents, as the normal position averages 2.8 mm above this line 4
- Traditional criteria requiring >5 mm descent may significantly underestimate the incidence of clinically relevant tonsillar herniation 4, 3
- Ventral tonsillar herniation (tonsils crossing a line bisecting the caudal medulla) correlates with headache presentation and medullary symptoms 3
Important Clinical Pitfalls
Do Not Assume All Tonsillar Herniation is Congenital
- Acquired tonsillar herniation can occur from various causes including cerebellar tonsil inflammation, craniofacial dysostosis, or increased intracranial pressure 5, 2, 6
- In cases of infectious mononucleosis with isolated cerebellar tonsil inflammation, tonsillar herniation may resolve spontaneously with conservative treatment 2
Recognize Atypical Presentations
- Scoliosis may be an important manifestation of subclinical tonsillar herniation, with the degree of tonsillar descent correlating with curve severity 4
- Children with craniofacial dysostosis (Apert, Crouzon, Pfeiffer syndromes) are at risk for acquired cerebellar tonsillar herniation and require screening 6