Ventrolateral pontomedullary junction cavernous malformation: illustrative case.

Area of Science:

• Neurosurgery
• Neurology

Background:

• Ventrolateral pontomedullary junction (PMJ) cavernous malformations pose surgical challenges due to their location near critical neurovascular structures.
• Preserving corticospinal tracts, vertebral artery, and cranial nerves is paramount for minimizing patient morbidity.

Purpose of the Study:

• To describe a tailored surgical approach for ventrolateral PMJ cavernous malformations presenting on the pial surface.
• To evaluate the safety and efficacy of this approach in achieving gross-total resection while preserving neurological function.

Main Methods:

• A modified far-lateral approach with limited occipital condyle drilling was utilized.
• Resection was performed along the lesion-brain plane under continuous neurophysiological monitoring.
• Lesion mobilization towards the pial opening facilitated resection, minimizing traction on eloquent tracts.

Main Results:

• Gross-total resection of the ventrolateral PMJ cavernous malformation was achieved.
• Transient worsening of abducens palsy occurred but ultimately improved beyond the preoperative baseline.
• No new permanent neurological deficits were observed postoperatively.

Conclusions:

• A tailored far-lateral corridor, combined with lesion mobilization, can enable safe resection of selected ventrolateral PMJ cavernous malformations with surface presentation.
• This technique minimizes traction on eloquent tracts, contributing to favorable surgical outcomes.