Case 13 Olfactory groove meningioma

Figure 13: MRI of the patient axial with contrast.

Clinical presentation

• A 62-year-old male patient presented with a condition that started four months ago with a fainting attack, followed by the development of dizziness two months later.
• The condition is associated with a diffuse, dull, aching headache that increases with stress and decreases with analgesics, not associated with vomiting.
• Fundus examination showed no papilledema.
• Motor functions are at full power.
• Sensory functions and sphincters are intact.

• Q1 : Could you tell the sequence of the MRI shown here? What clues lead you to your answer?
• It is a T1 with contrast, as the sinuses are enhancing. Venous sinus enhancement is important when evaluating contrast patterns of enhancement because it serves as a guide that the MRI was taken under optimal conditions.

• Q2: From the appearance of the lesion, what is its origin (both anatomical and pathological/microscopic)? What is the main blood supply to this extra-axial lesion?
• Anatomically, the lesion originates from the cribriform plate. Pathologically, it involves arachnoid cap cells. The main blood supply to the lesion is from the ethmoidal artery, which arises from the ophthalmic artery.

• Q3: During surgery for this lesion, what is the most critical area on the surface of the tumor related to important structures, and what are these important structures?
• The most critical surface is the postero-superior surface. It is located near important structures such as the anterior cerebral artery, optic nerve and chiasm, and the pituitary stalk. Sharp dissection is required in this area during surgery.