Stereotactic biopsies of brainstem lesions: which approach?

Abstract

Background Stereotactic biopsies for brainstem lesions are frequently performed to yield an accurate diagnosis and help guide subsequent management. In this study, we summarize our experience with different stereotactic approaches to brainstem lesions of different locations and discuss possible implications for safety and diagnostic yield. Methods We retrospectively analyzed 23 adult patients who underwent a stereotactic biopsy for brainstem lesions between October 2011 and December 2019. Depending on the location supra- or infratentorial, trajectories were planned. We assessed the postoperative complications during the hospital stay as well as the diagnostic yield. Results A supratentorial transfrontal approach was used in 16 (70%) cases, predominantly for lesions in the midbrain, upper pons, and medulla oblongata. An infratentorial, transcerebellar-transpeduncular approach was used in 7 (30%) cases mainly for lesions within the lower pons. All biopsies were confirmed to represent pathological tissue and a definitive diagnosis was achieved in 21 cases (91%). Three patients (13%) had transient weakness in the contralateral part of the body in the immediate postoperative period, which improved spontaneously. There was no permanent morbidity or mortality in this series of patients. Conclusion Lesions of various locations within the brainstem can be successfully targeted via either a supratentorial transfrontal or an infratentorial transcerebellar transpeduncular approach. Our high diagnostic yield of over 90% and the low rate of complications underlines the diagnostic importance of this procedure in order to guide the medical management of these patients.

The Role of Stereotactic Frame-Based Biopsy for Brainstem Tumors in the Era of Molecular-Based Diagnosis and Treatment Decisions

“…Regarding the approach, the transfrontal and transcerebellar routes are the two major surgical routes [ 11 , 15 , 16 , 17 ]; however, there is a paucity of evidence as to which approach is more suitable [ 13 , 14 , 18 ]. Dellaretti et al [ 12 ] reported that the transfrontal approach achieved a higher diagnostic rate (95%) than the transcerebellar approach (84%), but the difference was not statistically significant, similar to the observation in other studies [ 19 , 20 ]. For pediatric brainstem tumors, the diagnostic rate via the transcerebellar approach was 96% [ 13 ].…”

Response to letter: “Stereotactic biopsies of brainstem lesions: dilemma on the best trajectory”

“…On the other side, case series of brainstem stereotactic biopsies performed through a supratentorial transfrontal approach seemed not to show an increased complication rate [1,5]. Nevertheless, as discussed in our publication [2], we also believe that crossing the entire brainstem or part of it to reach a lesion has intrinsically more complication rate, as, in our experience, (transient) neurological deficits may appear without bleeding and not necessarily at the biopsy location. We also favor a transcerebellar transpeduncular approach as it is the shortest approach and avoids crossing the brainstem, as long as the lesion can be reached and biopsied.…”

Rediscovery of the transcerebellar approach: improving the risk-benefit ratio in robot-assisted brainstem biopsies

“…12 The TCA is considered more complex because of the necessity of a prone or semisitting position and a modified attachment of the stereotactic ring, respectively. 21,38 Robotic technology certainly enables a simplified application of the TCA, avoiding these restrictions as well as the disadvantages of the TFA (i.e., higher inaccuracy due to long trajectories, a small surgical corridor, and extensive effects on eloquent structures). In our opinion, the advantages of the TCA are a shorter trajectory length and a larger anatomical corridor, enabling the avoidance of eloquent tissue.…”