Author(s)
P. L. Purcell
J. P. Manning
R. A. Bly
S. A. Farley
S. C. Manning
Affiliation(s)
University Of Washington; Seattle Children's Hospital
Abstract:
Introduction: This study reviews our institution’s 15-year experience with surgical management of frontonasal dermoids and assesses how concordant the results of computed tomography (CT) and magnetic resonance imaging (MRI) were with surgical findings of intracranial extension. Methods: Cases at our tertiary care center were identified through radiology report query. Only cases of pathologically confirmed dermoid cysts were included. Operative findings and frequency of intracranial extension were reviewed. Receiver operating characteristic (ROC) curves were generated for CT and MRI detection of intracranial extension; ROC area equal to 1 indicates 100% sensitivity and specificity. Results: 92 children with frontonasal dermoids were identified. Mean age at diagnosis was 18.3 months (range: birth – 192 months). The most common surgical approaches were direct excision (78.4%), external rhinoplasty (9%), and transcranial/craniotomy (6.8%). Six cases (6.8%) had intracranial extension on surgical report. Of those, 5 had undergone CT imaging with 4 correctly identifying intracranial extension; 5 had undergone MRI with 3 correctly identifying intracranial extension. Areas under the ROC curves were calculated to be 0.8 for CT (95% CI [0.5, 1]) and 0.64 for MRI (95% CI [0.29, 1]). There was no significant difference between CT and MRI in ROC analysis, (p=0.3). Two cases with intracranial extension were successfully treated with endoscopic-assisted external rhinoplasty. Conclusion: Intracranial extension of frontonasal dermoids is rare, and few patients required craniotomy in our series. CT may be comparable to MRI at detecting intracranial extension, although MRI protocols have evolved over the course of the study.