Presentation
Acute onset psychosis.
Patient Data
6cm x 6.3cm x 4.5cm (AP x trans x CC) T1 isointense, T2 to slightly hyperintense, vividly contrast enhancing, diffusion restricting extra axial anterior cranial fossa mass arising from the olfactory groove and surrounding the falx anteriorly is demonstrated. Numerous small flow voids representing vessels are seen around the periphery of the lesion. The mass exerts significant local mass effect with cortical buckling and lateral displacement of the medial aspects of the frontal lobes and posterior displacement of the genu of the corpus callosum. The frontal horns of the lateral ventricles are splayed by the mass and the anterior cerebral arteries are displaced posteriorly and draped over the posterosuperior aspect of the mass.
Moderate surrounding T2/flair signal hyper intensity within frontal lobes and anterior temporal poles bilaterally representing vasogenic edema. The basal cisterns remain uneffaced. No uncal or transtentorial herniation.
The coronal imaging is significantly motion degraded however appears to extend through the cribriform plate into the superior nasal vault.
Note is made of a partially "empty sella".
Conclusion: Large anterior cranial fossa extraaxial mass straddling the falx with the imaging features of favoring olfactory groove meningioma.
MICROSCOPIC DESCRIPTION: Paraffin sections show a moderately hypercellular meningioma with a well developed syncytial architecture. Tumor cells have uniform nuclear features. No mitotic figures or areas of necrosis are identified and there is no evidence of brain invasion. Broad attachment to dura is identified.
DIAGNOSIS: Olfactory groove tumor: Meningioma.