Extensive extracranial growth of spheno-orbital meningioma: illustrative case

BACKGROUND: Spheno-orbital meningioma (SOM) typically presents with a classic triad of symptoms (i.e., proptosis, visual impairment, and ocular paresis), resulting from intraorbital tumor invasion. The authors present a very rare case of SOM in which the chief complaint was swelling of the left temporal region, which, to the best of their knowledge, has not been reported previously. OBSERVATIONS: The patient presented with marked extracranial extension to the left temporal region but unremarkable intraorbital extension, even on radiological examination. Physical examination of the patient showed almost no exophthalmos or restriction of left eye movement, consistent with the radiological findings. Four separate meningioma specimens were removed by extraction (i.e., one each from the intracranial, extracranial, and intraorbital segments of the tumor and one from the skull). The World Health Organization grade was 1 and the MIB-1 index was less than 1%, indicating a diagnosis of a benign tumor. LESSONS: SOM may be present even in patients with only temporal swelling and few ocular-related symptoms, and detailed imaging evaluations may be required to identify the tumor.