The Far-Lateral Transcondylar Approach to Pontomedullary Junction Brainstem Cavernomas

Background: Surgical resection of symptomatic brainstem cavernous malformations has been increasingly described by high-volume neurovascular centers. When managed conservatively, these lesions have a high rate of re-hemorrhage resulting in progressive neurologic decline. Surgical treatment is recommended for symptomatic, surgically accessible lesions.¹

Objective: A variety of surgical approaches to brainstem cavernomas of the pontomedullary junction have been described. The purpose of the study is to describe the advantage of the far lateral transcondylar approach for lateral pontomedullary junction brainstem cavernomas when compared with a standard retrosigmoid suboccipital approach.

Methods: Seven patients with lateral pontomedullary junction cavernomas surgically treated at our institution between 2005 and 2012 were retrospectively reviewed. The working angles afforded by the addition of the far-lateral transcondylar component of the exposure were compared with the degree of access obtained with the retrosigmoid approach alone.

Results: All patients presented to our institution with a history of symptomatic hemorrhage from a pontomedullary junction cavernoma. All lesions were resected via a far lateral transcondylar approach. Complete resection of the malformation was achieved in all cases. There was no postoperative mortality. Of the 7 patients, 4 were improved or neurologically stable on last follow up evaluation. Mean follow up was 16 months (range 3 to 42 months). The far-lateral transcondylar approach provided a superior surgical trajectory based on the two-point method² in each case.

Conclusion: Surgical resection of pontomedullary junction cavernomas is associated with a risk of significant surgical morbidity. Based on our institution's experience, the far lateral transcondylar approach affords an improved trajectory and reduces the risk of iatrogenic brainstem injury and cranial nerve dysfunction. The far lateral approach is recommended for treatment of lateral pontomedullary junction cavernous malformations.

References

References

1 Abla AA, Turner JD, Mitha AP, Lekovic G, Spetzler RF. Surgical approaches to brainstem cavernous malformations. Neurosurg Focus 2010;29(3):E8

2 Brown AP, Thompson BG, Spetzler RF. The Two-Point Method? Evaluating Brain Stem Lesions. 1996;12:1–6