title: Proposed Diagnostic Criteria, Classification Schema, and Review of Literature of Notochord-Derived Ecchordosis Physaliphora.
abstract: Ecchordosis physaliphora (EP) is a benign notochordal remnant derived from ectopic nests found along the craniospinal axis. It typically presents asymptomatically and is diagnosed using classic radiologic features, particularly location, T1-hypointensity, T2-hyperintensity, and lack of enhancement following gadolinium (Gd) contrast administration. Distinguishing EP from its malignant counterpart, chordoma, is of paramount importance, given the aggressive nature of the latter. Advances in imaging and immunohistochemistry have aided in diagnosis to an extent but, to our knowledge, identification of the genetic fingerprint of EP has yet to take place. Further cytological analysis of these lesions in search of a genetic link is warranted. We propose here a set of diagnostic criteria based on features consistently cited in the literature. In this literature review, 23 case reports were identified and collated into a summary of symptomatic cases of ecchordosis physaliphora. An illustrative case report of two patients was also included.
authors.affiliation: Department of Neurosurgery, Cooper Neurological Institute, Cooper University Hospital.
authors.forename: Carlito
authors.initials: C
authors.lastname: Lagman
authors.affiliation: Center for Neurosurgical Outcomes Research, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center.
authors.forename: Kunal
authors.initials: K
authors.lastname: Varshneya
authors.affiliation: Department of Neurosurgery, Cedars-Sinai Medical Center.
authors.forename: J Manuel
authors.initials: JM
authors.lastname: Sarmiento
authors.affiliation: Department of Neurosurgery, Cooper Neurological Institute, Cooper University Hospital.
authors.forename: Alan R
authors.initials: AR
authors.lastname: Turtz
authors.affiliation: Department of Neurological Surgery, Vanderbilt University Medical Center.
authors.forename: Rohan V
authors.initials: RV
authors.lastname: Chitale
keywords: chordoma; ecchordosis physaliphora; notochordal remnant; retroclival lesion