Natural and surgical history of Chiari malformation Type I in the pediatric population

Abstract

<jats:sec> <jats:title>OBJECT</jats:title> <jats:p>The natural and surgical history of Chiari malformation Type I (CM-I) in pediatric patients is currently not well described. In this study the authors discuss the clinical and radiological presentation and outcomes in a large cohort of pediatric CM-I patients treated with either conservative or surgical management.</jats:p></jats:sec> <jats:sec> <jats:title>METHODS</jats:title> <jats:p>The authors retrospectively reviewed 95 cases involving pediatric patients with CM-I who presented between 2004 and 2013. The patients ranged in age from 9 months to 18 years (mean 8 years) at presentation. The cohort was evenly split between the sexes. Twenty-five patients underwent posterior fossa decompression (PFD) with either dural splitting or duraplasty. Seventy patients were managed without surgery. Patients were followed radiologically (mean 44.8 months, range 1.2–196.6 months) and clinically (mean 66.3 months, range 1.2–106.5 months).</jats:p></jats:sec> <jats:sec> <jats:title>RESULTS</jats:title> <jats:p>Seventy patients were treated conservatively and followed with serial outpatient neurological and radiological examinations, whereas 25 patients were treated with PFD. Of these 25 surgical patients, 11 were treated with duraplasty (complete dural opening) and 14 were treated with a dura-splitting technique (incomplete dural opening). Surgical intervention was associated with better clinical resolution of symptoms and radiological resolution of tonsillar ectopia and syringomyelia (p = 0.0392). Over the course of follow-up, 20 (41.7%) of 48 nonsurgical patients who were symptomatic at presentation experienced improvement in symptoms and 18 (75%) of 24 symptomatic surgical patients showed clinical improvement (p = 0.0117). There was no statistically significant difference in resolution of symptoms between duraplasty and dura-splitting techniques (p = 0.3572) or between patients who underwent tonsillectomy and tonsillopexy (p = 0.1667). Neither of the 2 patients in the conservative group with syrinx at presentation showed radiological evidence of resolution of the syrinx, whereas 14 (87.5%) of 16 patients treated with surgery showed improvement or complete resolution of syringomyelia (p = 0.0392). In the nonsurgical cohort, 3 patients (4.3%) developed new or increased syrinx.</jats:p></jats:sec> <jats:sec> <jats:title>CONCLUSIONS</jats:title> <jats:p>The overwhelming majority of CM-I patients (92.9%) managed conservatively do not experience clinical or radiological progression, and a sizeable minority (41.7%) of those who present with symptoms improve. However, appropriately selected symptomatic patients (sleep apnea and dysphagia) and those presenting with syringomyelia should be considered surgical candidates because of the high rates of clinical (75%) and radiological improvement (87.5%).</jats:p></jats:sec>

Unexpected Progression of Tonsillar Herniation in Two Pediatric Cases with Chiari Malformation Type I and Review of the Literature

“…Currently, there is no consensus on the criteria for selection of patients with CM-1 for surgery; however, there are various studies and arguments on the advantages of conservative management and surgery in CM-1 [3, 28]. The most common reasons for surgical treatment during the follow-up period are remarked as medically refractory and persistent headaches, sleep apnea, and changes in syrinx [14].…”

“…Chiari malformation type 1 (CM-1), which is the most common type of CM, is characterized with tonsillar herniation with cut-off 5 mm below the foramen magnum, besides there is no consensus on radiological diagnostic criteria [1-3]. Additionally, the pathogenesis of this disease still remains unclear with suggestion of various genetic, nongenetic, and epigenetic theories [1].…”

“…Cases are mostly asymptomatic at the time of diagnosis and the symptoms of presentation may change with age [1]. Adults most commonly present with posterior headache and/or neck pain, nausea and vomiting, and vertigo; children may also have occult findings along with ataxia, sensory and motor deficits, and lower cranial nerve abnormalities like oropharyngeal dysfunction especially in those younger than 2 years old [3-6]. …”

Spontaneous Resolution of Chiari 1-Associated Syringomyelia: A Report of Two Cases

“…A recent study by Pomeraniec et al [7] retrospectively reviewed 95 pediatric cases of CM1. Seventy patients were treated conservatively and then followed with serial outpatient neurological and radiological examinations.…”

Management of Chiari I deformity in Children and Adolescents: A report from the Consensus Taskforce of the Brazilian Society of Pediatric Neurosurgery

“…18 Similarly, Pomeraniec et al studied 95 CID pediatric patients and concluded that 92.9% of the patients managed conservatively did not experience clinical or radiological progression, whereas 41.7% of those who had presented with symptoms improved during follow-up. 19 Lastly, Langridge et al have recently performed a systematic review of the natural history and conservative management of adult and pediatric patients with CID. Fifteen papers were included in their meta-analysis, allowing for these authors to conclude that the natural history of mild symptomatic and asymptomatic CID is relatively benign and nonprogressive, and that it is reasonable to observe asymptomatic patients and subjects with mild symptoms even in the presence of significant tonsillar descent or syringomyelia.…”