A case series of percutaneous transforamen ovale biopsies in cavernous sinus lesions

The majority of cavernous sinus lesions are meningiomas, for which treatment (fractioned radiotherapy or radiosurgery), if indicated, is usually initiated upon image-based diagnosis. However, this region can be affected by a wide variety of pathological processes and the risk of misdiagnosis exists. As pathological diagnosis can be obtained by biopsy through the foramen ovale in selected cases, we asked the question as to whether systematically performing this procedure before treatment would provide additional, relevant diagnostic information. All the cases referred to our department between January 2008 and December 2019 for cavernous sinus lesions that were considered for treatment and anatomically suitable for transforamen ovale biopsy were included. Outcomes and subsequent treatment or follow-up data were collected. Thirty-five patients were included. Twenty-six were highly suspected to have meningioma or schwannoma at imaging, among whom biopsy allowed diagnosis confirmation in 17 cases (65%). For the nine patients for whom biopsy was indicated upon suspected malignancy or inflammatory disease on imaging, biopsy revealed three meningiomas and one lymphoma and was not contributory in five cases (56%), three of which underwent open surgery. Three patients (8.5%) had persistent neuralgia at the last follow-up. When cavernous sinus meningioma or schwannoma is highly suspected upon predefined imaging criteria by an experienced neuroradiologist, invasive exploration before treatment does not seem to be indicated. Otherwise, transforamen ovale biopsy might be consider in selected cases as a minimally invasive option to obtain pathological analysis.