Page 41 - WNS 2022 Program Book-Final version

Spontaneous Resolution of Chiari I Malformation in an Adult. A Case
Report and Literature Review
Barbara Lazio, MD, FAANS, Providence-Swedish NeurosurgeryWestern
Washington
Co-authors: Dahlia Scher, BSc, University of California San Diego
Introduction:
With the wide availability of magnetic resonance imaging for brain and cervi-
cal spine complaints, adult patients are diagnosed with Chiari I malformation
more frequently. While there are few reports of spontaneous resolution of
Chiari I malformation in adults, it is important to consider when choosing con-
servative versus surgical management in minimally symptomatic and asymp-
tomatic patients.
Case Report:
A woman presented to a neurosurgeon at age 55 with a two-year history of
left-sided headaches and left facial numbness. She had no association of
headache with position, cough, or Valsalva. MRI brain demonstrated cerebel-
lar tonsillar ectopia 12 mm below the foramen magnum. Due to atypical
symptoms, surgical management was not recommended. She presented ten
years later with dizziness and gait disturbance. MRI cervical spine showed
resolution of cerebellar tonsillar ectopia and no syringomyelia.
Methods:
A comprehensive literature review was conducted on PubMed, Google Schol-
ar and Web of Science with keywords “Chiari I malformation,” “spontaneous
resolution,” and “adult.” Articles including exclusively pediatric patients and
patients treated surgically were excluded. Articles including treatment for
other intracranial pathologies were excluded.
Results and Conclusions:
We identified sixteen cases of spontaneous regression of adult Chiari I mal-
formation in the literature. The case presented was similar to the 16 previous-
ly reported cases in the nonoperative treatment. Unlike the previous cases,
this patient never had symptoms attributable to Chiari I malformation. The
natural history of minimally and asymptomatic Chiari I malformation in adults
is not well documented radiographically. This case illustrates radiographic
resolution of cerebellar tonsillar ectopia and strengthens the argument for
conservative management in patients with radiographic cerebellar tonsillar
ectopia and atypical symptoms.
Figure 1. A. Sagittal T1 brain MRI 2011 demonstrating 12 mm cerebellar
tonsillar ectopia B. Sagittal T2 cervical spine MRI 2021 demonstrating resolu-
tion of cerebellar tonsillar ectopia

A B

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