Here's a nice example of a posterior Frontal Glioma that was removed under mapping using General Anesthesia. This is a 42-year-old male who presented with multiple seizures. MRI evaluation revealed relatively minimally enhancing Glioma which turned out eventually to be an Anaplastic Astrocytoma affecting the posterior frontal lobe. Functional MRI revealed the location of the motor cortex to be at least two gyri posterior to the posterior aspect of the tumor. I elected to use mapping under general anesthesia because during the removal of the subcortical portion of the tumor, the motor tracts could become very intimately associated with the capsule of the tumor. The motor fibers or the descending motor fibers travel more anteriorly to reach the Corona Radiata and therefore subcortical mapping can add another level of safety in aggressive resection of the tumor. Here's a wide craniotomy. You can see the location of the tumor that is demarcated using the black suture. I went ahead and did motor mapping. You can see the location of the motor cortex as expected based on functional MRI. This mapping methodology allowed me to determine the appropriate threshold for subcortical mapping of the motor fibers. Standard techniques were used for resection of the tumor. The peeled resection technique followed by disconnection of the tumor from the surrounding white matter tracts, as demonstrated here. I expect to expose the Sylvian vessels along the inferior aspect of the tumor. Here's the Sylvian fissure. The more superficial part of the tumor was removed. Here are the M2 branches within the fissure. Again, subcortical mapping was used for aggressive remove of the tumor, more posteriorly. In this case, no activation was noted upon removal of the tumor. Again, along its more posterior sections. Post-operative MRI revealed adequate removal of the tumor and this patient recovered from his surgery without any deficits. Thank you.
Please login to post a comment.