Visual Loss from Sphenocavernous Meningioma with Intranasal and Sphenoid Sinus Extension, the Conundrum Approach: Endoscopic, Craniotomy, Both, Sequence?

Introduction: Optic nerve compression laterally from sphenocavernous meningiomas, and medially from the intra nasal and sphenoid sinus extension could be tackled with open craniotomy or endoscopic intranasally. While both approaches may be ultimately required the timing and sequence of the approaches poses a dilemma.

Methods: A 45-year-old woman presented with 6 months progressive left eye blurred vision. MRI ([Fig. 1]) shows the intracranial and intranasal extension of the meningioma. Visual acuity was 20/60 and preoperative visual fields as illustrated in ([Fig. 2]). In addition, she also had left eye proptosis and hyperostosis of the orbital walls. The optic nerve was noted to be compressed both medially (intranasal) and laterally (intracranial). Endonasal and open craniotomy approaches were considered, and craniotomy was chosen as initial approach given the proptosis, the large intracranial component, and the feasibility of intracranial optic canal decompression.

Results: A modified cranio-orbito-zygomatic approached was performed and the intra-cranial extra cavernous portion of tumor was resected. The bony optic canal was deroofed and the falciform ligament was divided to completely release the optic nerve. Postoperative MRI is shown in [Fig. 3]. At 3 months visit, the patient reported subjective improvement and visual field test confirmed the same ([Fig. 3]). No further intervention was therefore envisaged.

At 6 months visit she reported deteriorating vision as seen on new visual field tests ([Fig. 4]). A new orbital MRI ([Fig. 4]) revealed no growth of the residual intranasal tumor or worsening of ON compression. Due to this new worsening, the patient is now being counselled for endoscopic endonasal decompression of optic nerve and resection of intra-nasal portion of the tumor.

Conclusion: This case brings forth the dilemma we face in the skull base arena vis a vis the approach to be adopted and the timing and sequence of such. Should endoscopic surgery have been performed first; or perhaps right away after the craniotomy to prevent this late decline in vision?