Clinical question: 43-year-old female with pseudotumor cerebri, CRS with associated left anterior ethmoid encephalocele versus mucocele. Evaluate for encephalocele involving paranasal sinuses. Signs and symptoms: As above. Pre- and postenhanced brain MRI:Negative diffusion weighted series.Examination demonstrate a small bony defect of the left fovea ethmoidalis with evidence of herniation of the left frontal lobe and minimally of the CSF through the defect into the left anterior ethmoid air cells. There is also a bony defect along the posterior wall of left frontal sinus inferior with resultant herniation of the left frontal lobe into the left frontal sinus and with slight extension across the midline to the right. The herniated left frontal lobe extends approximately 22 mm inferiorly into the left anterior ethmoid. The encephalocele in the left anterior ethmoid measures approximately 23 x 13 mm (axial T2 series 601 image 15) and 15 x 19 mm in transaxial dimensions in the frontal sinuses (axial T2 series 601 image 17).There is no detectable signal abnormality of the frontal lobe intracranially or its herniated segment within the left frontal and left ethmoid air cells. There is no convincing evidence of any mass effect/remodeling of the left lamina papyracea.The anatomical morphology and signal intensity of brain parenchyma is otherwise within normal on all MRI sequencesUnremarkable sacral cortex, cortical sulci, ventricular system and CSF spaces otherwise and with normal brain myelination. Post enhanced images demonstrate no abnormal enhancement of brain parenchyma or the meninges.Unremarkable images through the orbits and including axial fat sat post enhanced series.Normal signal intensity of the calvarium and soft tissues of the scalp without abnormal enhancement.Paranasal sinuses are well pneumatized and there is evidence of a small focus of mucosal thickening in the dorsal aspect of the right maxillary sinus. Bilateral mastoid air cells and middle ear cavities demonstrate normal pneumatization signal patterns.
1.Evidence of left anterior ethmoid and left frontal encephalocele as detailed. The herniated left frontal lobe into the left frontal sinus demonstrate slight extension across the midline to the right frontal sinus. Encephalocele extends approximately 22 mm inferiorly into the left anterior ethmoid. Bony defects inferiorly along the posterior wall of left frontal sinus as well as left fovea ethmoidalis.2.Unremarkable pre and post enhanced brain MRI otherwise.