Journal of Neurosurgery
Best of 2016
Francisco A. Ponce, Wael F. Asaad, Kelly D. Foote, William S. Anderson, G. Rees Cosgrove, Gordon H. Baltuch, Kara Beasley, Donald E. Reymers, Esther S. Oh, Steven D. Targum, Gwenn S. Smith, Constantine G. Lyketsos, and Andres M. Lozano
This report describes the stereotactic technique, hospitalization, and 90-day perioperative safety of bilateral deep brain stimulation (DBS) of the fornix in patients who underwent DBS for the treatment of mild, probable Alzheimer's disease (AD).
The ADvance Trial is a multicenter, 12-month, double-blind, randomized, controlled feasibility study being conducted to evaluate the safety, efficacy, and tolerability of DBS of the fornix in patients with mild, probable AD. Intraoperative and perioperative data were collected prospectively. All patients underwent postoperative MRI. Stereotactic analyses were performed in a blinded fashion by a single surgeon. Adverse events (AEs) were reported to an independent clinical events committee and adjudicated to determine the relationship between the AE and the study procedure.
Between June 6, 2012, and April 28, 2014, a total of 42 patients with mild, probable AD were treated with bilateral fornix DBS (mean age 68.2 ± 7.8 years; range 48.0–79.7 years; 23 men and 19 women). The mean planned target coordinates were x = 5.2 ± 1.0 mm (range 3.0–7.9 mm), y = 9.6 ± 0.9 mm (range 8.0–11.6 mm), z = −7.5 ± 1.2 mm (range −5.4 to −10.0 mm), and the mean postoperative stereotactic radial error on MRI was 1.5 ± 1.0 mm (range 0.2–4.0 mm). The mean length of hospitalization was 1.4 ± 0.8 days. Twenty-six (61.9%) patients experienced 64 AEs related to the study procedure, of which 7 were serious AEs experienced by 5 patients (11.9%). Four (9.5%) patients required return to surgery: 2 patients for explantation due to infection, 1 patient for lead repositioning, and 1 patient for chronic subdural hematoma. No patients experienced neurological deficits as a result of the study, and no deaths were reported.
Accurate targeting of DBS to the fornix without direct injury to it is feasible across surgeons and treatment centers. At 90 days after surgery, bilateral fornix DBS was well tolerated by patients with mild, probable AD.
Clinical trial registration no.: NCT01608061 (clinicaltrials.gov)
Yan Michael Li, Dima Suki, Kenneth Hess, and Raymond Sawaya
Glioblastoma multiforme (GBM) is the most common and deadliest primary brain tumor. The value of extent of resection (EOR) in improving survival in patients with GBM has been repeatedly confirmed, with more extensive resections providing added advantages. The authors reviewed the survival of patients with significant EORs and assessed the relative benefit/risk of resecting 100% of the MRI region showing contrast-enhancement with or without additional resection of the surrounding FLAIR abnormality region, and they assessed the relative benefit/risk of performing this additional resection.
The study cohort included 1229 patients with histologically verified GBM in whom ≥ 78% resection was achieved at The University of Texas MD Anderson Cancer Center between June 1993 and December 2012. Patients with > 1 tumor and those 80 years old or older were excluded. The survival of patients having 100% removal of the contrast-enhancing tumor, with or without additional resection of the surrounding FLAIR abnormality region, was compared with that of patients undergoing 78% to < 100% EOR of the enhancing mass. Within the first subgroup, the survival durations of patients with and without resection of the surrounding FLAIR abnormality were subsequently compared. The data on patients and their tumor characteristics were collected prospectively. The incidence of 30-day postoperative complications (overall and neurological) was noted.
Complete resection of the T1 contrast-enhancing tumor volume was achieved in 876 patients (71%). The median survival time for these patients (15.2 months) was significantly longer than that for patients undergoing less than complete resection (9.8 months; p < 0.001). This survival advantage was achieved without an increase in the risk of overall or neurological postoperative deficits and after correcting for established prognostic factors including age, Karnofsky Performance Scale score, preoperative contrast-enhancing tumor volume, presence of cyst, and prior treatment status (HR 1.53, 95% CI 1.33–1.77, p < 0.001). The effect remained essentially unchanged when data from previously treated and previously untreated groups of patients were analyzed separately. Additional analyses showed that the resection of ≥ 53.21% of the surrounding FLAIR abnormality beyond the 100% contrast-enhancing resection was associated with a significant prolongation of survival compared with that following less extensive resections (median survival times 20.7 and 15.5 months, respectively; p < 0.001). In the multivariate analysis, the previously treated group with < 53.21% resection had significantly shorter survival than the 3 other groups (that is, previously treated patients who underwent FLAIR resection ≥ 53.21%, previously untreated patients who underwent FLAIR resection < 53.21%, and previously untreated patients who underwent FLAIR resection ≥ 53.21%); the previously untreated group with ≥ 53.21% resection had the longest survival.
What is believed to be the largest single-center series of GBM patients with extensive tumor resections, this study supports the established association between EOR and survival and presents additional data that pushing the boundary of a conventional 100% resection by the additional removal of a significant portion of the FLAIR abnormality region, when safely feasible, may result in the prolongation of survival without significant increases in overall or neurological postoperative morbidity. Additional supportive evidence is warranted.
Robert F. Spetzler, Cameron G. McDougall, Joseph M. Zabramski, Felipe C. Albuquerque, Nancy K. Hills, Jonathan J. Russin, Shahram Partovi, Peter Nakaji, and Robert C. Wallace
The authors report the 6-year results of the Barrow Ruptured Aneurysm Trial (BRAT). This ongoing randomized trial, with the final goal of a 10-year follow-up, compares the safety and efficacy of surgical clip occlusion and endovascular coil embolization in patients presenting with subarachnoid hemorrhage (SAH) from a ruptured aneurysm. The 1- and 3-year results of this trial have been previously reported.
In total, 500 patients with an SAH met the entry criteria and were enrolled in the study. Of these patients, 471 were randomly assigned to the treatments: 238 to surgical clipping and 233 to endovascular coiling. Six patients who died before treatment and 57 patients with nonaneurysmal SAHs were excluded, leaving a total of 408 patients who underwent clipping (209 assigned) or coiling (199 assigned). Whether to treat patients within the assigned group or to cross over patients to the other group was at the discretion of the treating physician; 38% (75/199) of the patients assigned to coiling were crossed over to clipping and 1.9% (4/209) assigned to clipping were crossed over to coiling. The outcome data were collected by a dedicated nurse practitioner. The primary outcome analysis was based on the assigned treatment group; poor outcome was defined as a modified Rankin Scale (mRS) score > 2 and was independently adjudicated. Six years after randomization, 336 (82%) of 408 patients who had been treated were available for examination.
On the basis of an mRS score of > 2, and similar to the results at the 3-year follow-up, no significant difference in outcomes (p = 0.24) was detected between the 2 treatment groups. Complete aneurysm obliteration at 6 years was achieved in 96% (111/116) of the clipping group and in 48% (23/48) of the coiling group (p < 0.0001). In the period between the 3- and 6-year follow-ups, 3 additional patients assigned to coiling and none assigned to clipping received retreatment, for overall retreatment rates of 4.6% (13/280) for clipping and 16.4% (21/128) for coiling (p < 0.0001).
When aneurysm location was considered, the 6-year results continued to match the previously reported results, with no difference in outcome for anterior circulation aneurysms at most time points. Of the anterior circulation aneurysms assigned to coiling treatment, 42% (70/168) were crossed over to clipping treatment. The outcomes for posterior circulation aneurysms continued to favor coiling. The randomization process was unexpectedly skewed, with 18 of 21 treated aneurysms of the posterior inferior cerebellar artery (PICA) being assigned to clipping, but even when PICA aneurysms were removed from the analysis, outcomes for the posterior circulation aneurysms still favored coiling.
Although BRAT was statistically underpowered to detect small differences, these results suggest little difference in outcome between the 2 treatments for anterior circulation aneurysms. This was not the case for the posterior circulation aneurysms, where coil embolization appeared to provide a sustained advantage over clipping. Aneurysm obliteration rates in BRAT were significantly lower and retreatment rates significantly higher in the patients undergoing coiling than in those undergoing clipping. However, despite the fact that retreatment rates were higher after coiling, no recurrent hemorrhages were known to have occurred in patients undergoing coiling in BRAT who were followed up for 6 years. Sufficient questions remain about the relative benefits of the 2 treatment modalities to warrant further well-designed randomized trials.