Frameless robot-assisted stereotactic biopsies for lesions of the brainstem-a series of 103 consecutive biopsies

Comparative Analysis of Efficacy and Safety of Frame-Based, Frameless, and Robot-Assisted Stereotactic Brain Biopsies: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVES

For 50 years, frame-based stereotactic brain biopsy has been the "gold standard" for its high diagnostic yield and safety, especially for complex or deep-seated lesions. Over the past decade, frameless and robotic alternatives have emerged. This report evaluates and compares the outcomes, diagnostic yield, and safety of these methods.

METHODS

Major databases were screened for studies reporting data on diagnostic yield, postoperative hemorrhage, neurological deficits, and mortality after frame-based, robot-assisted or neuronavigation-assisted frameless biopsies. Meta-analysis with random-effect modeling was performed to compare diagnostic yield, operative duration, length of stay, complications, and mortality.

RESULTS

A total of 92 studies were included with 9801 patients in the frame-based group, 2665 in the robot-assisted group, and 1862 in the frameless group. Pooled diagnostic yield rates were 97% (96%-98%, I 2 = 49%) in robot-assisted, 95% (94%-96%, I 2 = 74%) in frame-based, and 94% (91%-96%, I 2 = 55%) frameless groups with a statistically significant difference ( P < .01, I 2 = 71%). The mean total operative duration including anesthesia, system setup, patient registration, trajectory planning, and skin incision to closure was significantly shorter in the robot-assisted group (76.6 vs 132.7 vs 97.3 minutes, P < .01). The duration from skin incision to closure was comparable between the groups (robot-assisted: 37.8 mins, frame-based: 42.6 minutes, frameless: 58.2 minutes; P = .23). Pooled rates of symptomatic hemorrhage (0.005% vs 0.009% vs 0.007, P = .71, I 2 = 34%), asymptomatic hemorrhage (4% vs 3% vs 3%, P = .64, I 2 = 93%), transient neurological deficit (3% vs 2% vs 2%, P = .5, I 2 = 72%), permanent neurological deficit (0.001% vs 0.001% vs 0.0002, P = .78, I 2 = 47%), and mortality (0% vs 0.001% vs 0.006%, P < .01, I 2 = 10%) were similar between groups. Deaths were mainly due to postprocedural hemorrhage (robotic: 46%, frame-based: 48%, frameless: 72%).

CONCLUSION

Robot-assisted biopsy is not inferior in diagnostic yield and safety to the gold standard frame-based and neuronavigation-assisted frameless biopsy methods.

Frameless Stereotactic Biopsy of Brainstem Tumors Using the Stealth Autoguide: A Technical Note

BACKGROUND AND OBJECTIVES

In the molecular era of neuro-oncology, it is increasingly necessary to obtain tissue for next-generation sequencing and methylome profile for prognosis and targeted oncological management. Brainstem tumors can be technically challenging to biopsy in the pediatric population. Frame-based and frameless techniques have previously been described and proven to be safe and efficacious in children. Recent cranial robotic guidance platforms have augmented the fluency of frameless stereotactic approaches, but the technical nuances of these procedures in children are not often discussed. We present a technical workflow for frameless stereotactic biopsy of brainstem tumors in children using the Medtronic Stealth Autoguide cranial robotic guidance platform and examine safety and efficacy of this surgical approach.

METHODS

A minimally invasive, frameless, transcerebellar approach is described, including operative steps and workflow. We assessed operative times, diagnostic accuracy and yield, and complication rates.

RESULTS

Five patients underwent biopsy with the technique described. The youngest patient in our series was of 2 years. The intended target was achieved on postoperative imaging in all cases, and diagnostic tissue was obtained in all 5 patients. One patient had a clinically insignificant hemorrhage.

CONCLUSION

Frameless stereotactic biopsy of the brainstem can be performed safely, efficiently, and accurately using the Medtronic Stealth Autoguide robotic platform in children as young as 2 years.

Robot-assisted stereotactic brain biopsy: A systematic review and meta-analysis

INTRODUCTION

Intracranial lesions often require tissue diagnosis through stereotactic biopsies. Originating in the 1970s, this technique has progressed, but limitations and risks persist. Recently, robot-assisted techniques have made strides, providing the potential for safer and more precise procedures. This study assesses the effectiveness and safety of robot-assisted brain biopsies.

METHODS

Following Cochrane and PRISMA guidelines, PubMed, Embase, and Web of Science were searched for publications up to July 2024. Outcomes assessed included neurological deficits, hemorrhage, mortality, target point error, operative time, and length of stay. Data extraction and bias assessment were conducted using standardized methods, and statistical analysis was performed using R software.

RESULTS

In this meta-analysis, 27 papers were included, involving 2605 patients. The gender distribution was 1448 males to 1141 females. The mean error in millimeters for the entry point error was 1.04 (95%CI: 0.72-1.37), while the target point error was 1.08 (95%CI: 0.49-1.66). The mean operative time was 52.45 min (95%CI: 37.83-67.07). Diagnostic yield had an estimated rate of 98% (95%CI: 97-98%; I²=31%). The length of hospital stay was 4.64 days (95%CI: 3.13, 6.14), from admission to discharge. The postoperative hemorrhage had an estimated risk of 6% (95%CI: 4-9%; I²=71%), while for transient neurological deficits, it was 4% (95%CI: 2-6%; I²=60%). Finally, the death related to the procedure was found to have an estimated risk of 0% (95%CI: 0-0%; I²=0%).

CONCLUSION

Our study found that the diagnostic yield of stereotactic brain biopsy, especially with robotic assistance, has proven to be highly effective. Robot-assisted biopsies also seems to reduce operative times and demonstrate high precision with low entry point error and target point error. Additionally, complication rates appear to be relatively low, and the average hospital stay is favorably short, underscoring the advantages of robotic assistance in stereotactic brain biopsy procedures.

Frame-based stereotactic biopsies of brainstem lesions - Monocentric comparison of the transfrontal and the suboccipital-transcerebellar approach over a 16-year period

Both the transfrontal and the suboccipital-transcerebellar approach are frequently used trajectories for frame-based stereotactic biopsies of brainstem lesions. Nevertheless, it remains unclear which approach is more favorable in terms of complications, diagnostic success and outcome, especially considering the location of the lesion within the brainstem. This study compared the safety and diagnostic yield of these two approaches. Furthermore, a brainstem zone model was created to answer the question, whether there is a favorable approach depending on the location of the lesion in the brainstem. A retrospective analysis of 84 consecutive cases of frame-based stereotactic biopsies for brainstem lesions via either transfrontal or suboccipital-transcerebellar approaches over a 16-year period was performed. Clinical and surgical data regarding trajectories, histopathology, complications and outcome was collected. The brainstem was divided in anatomical zones to compare the use of the two approaches depending on the location of the lesions. A total of n = 84 cases of stereotactic biopsies for brainstem lesions were performed. In 36 cases the suboccipital-transcerebellar approach was used, while in 48 cases surgery was performed via the transfrontal approach. The patient's demographic data were comparable between the two approaches. Overall diagnostic yield was 90.5% (93.8% transfrontal vs. 86.1% suboccipital, p = 0.21, Risk Difference (RD) 0.077, CI [-0.0550, 0.2090]). Complications occurred in 11 cases (total complication rate: 13.1%; 12.5% transfrontal vs. 13.9% suboccipital, p = 0.55, RD 0.014, CI [-0.1607, 0.1327]). The brainstem model showed a more frequent use of the suboccipital approach in lesions of the dorsal pons. The transfrontal approach was used more frequently in mesencephalic targets. No significant differences in terms of complications and diagnostic yield were observed, even though complications in medullary lesions appeared higher using the transfrontal approach. This study showed, that if the approaches are used for their intended target locations there are no significant differences between the transfrontal and the suboccipital-transcerebellar approach for frame-based stereotactic biopsies of brainstem lesions in terms of diagnostic yield and safety. Therefore, our data suggests that both approaches should be considered for stereotactic biopsy of brainstem lesions.

Safety and Technical Efficacy of Pediatric Brainstem Biopsies: An Updated Meta-Analysis of 1000+ Children

BACKGROUND

Brainstem tumors represent ∼10% of pediatric brain tumors, ∼80% of these are diffuse midline glioma. Given invariably poor prognosis in diffuse midline glioma, there continues to be immense variation worldwide in performing biopsy of these lesions. Several contemporary studies in recent years have provided new data to elucidate the safety profile of biopsy and an updated meta-analysis is thus indicated.

METHODS

We found 29 studies of pediatric brainstem biopsy in the last 20 years (2003-2023, 1002 children). We applied meta-analysis of proportions using a random-effects model to generate point estimates, confidence intervals, and measures of heterogeneity.

RESULTS

Eighty-seven percent of procedures were stereotactic needle biopsies (of these, 62% with a frame, 14% without frame, and 24% robotic.) Biopsy resulted in a histological diagnosis ("technical yield") in 96.8% of cases (95% CI 95.4-98.2). Temporary complications were seen in 6% (95 CI 4-8), with the most common neurological complications being 1) cranial nerve dysfunction, 2) worsening or new ataxia, and 3) limb weakness. Permanent complications (excluding death) were seen in 1% (95% CI 0.5-2), most commonly including cranial nerve dysfunction and limb weakness. Five deaths were reported in the entire pooled cohort of 1002 children (0.5%).

CONCLUSIONS

When counseling families on the merits of brainstem biopsy in children, it is reasonable to state that permanent morbidity is rare (<2%). If biopsy is performed specifically to facilitate enrollment in clinical trials requiring a molecular diagnosis, the risks of biopsy outlined here should be weighed against potential benefits of trial enrollment.

Stereotactic frame-based biopsy of infratentorial lesions via the suboccipital-transcerebellar approach with the Zamorano-Duchovny stereotactic system-a retrospective analysis of 79 consecutive cases

OBJECTIVE

Lesions of the posterior fossa (brainstem and cerebellum) are challenging in diagnosis and treatment due to the fact that they are often located eloquently and total resection is rarely possible. Therefore, frame-based stereotactic biopsies are commonly used to asservate tissue for neuropathological diagnosis and further treatment determination. The aim of our study was to assess the safety and diagnostic success rate of frame-based stereotactic biopsies for lesions in the posterior fossa via the suboccipital-transcerebellar approach.

METHODS

We performed a retrospective database analysis of all frame-based stereotactic biopsy cases at our institution since 2007. The aim was to identify all surgical cases for infratentorial lesion biopsies via the suboccipital-transcerebellar approach. We collected clinical data regarding outcomes, complications, diagnostic success, radiological appearances, and stereotactic trajectories.

RESULTS

A total of n = 79 cases of stereotactic biopsies for posterior fossa lesions via the suboccipital-transcerebellar approach (41 female and 38 male) utilizing the Zamorano-Duchovny stereotactic system were identified. The mean age at the time of surgery was 42.5 years (± 23.3; range, 1-87 years). All patients were operated with intraoperative stereotactic imaging (n = 62 MRI, n = 17 CT). The absolute diagnostic success rate was 87.3%. The most common diagnoses were glioma, lymphoma, and inflammatory disease. The overall complication rate was 8.7% (seven cases). All patients with complications showed new neurological deficits; of those, three were permanent. Hemorrhage was detected in five of the cases having complications. The 30-day mortality rate was 7.6%, and 1-year survival rate was 70%.

CONCLUSIONS

Our data suggests that frame-based stereotactic biopsies with the Zamorano-Duchovny stereotactic system via the suboccipital-transcerebellar approach are safe and reliable for infratentorial lesions bearing a high diagnostic yield and an acceptable complication rate. Further research should focus on the planning of safe trajectories and a careful case selection with the goal of minimizing complications and maximizing diagnostic success.

Feasibility and Accuracy of Robot-Assisted, Stereotactic Biopsy Using 3-Dimensional Intraoperative Imaging and Frameless Registration Tool

BACKGROUND

Robot-assisted stereotactic biopsy is evolving: 3-dimensional intraoperative imaging tools and new frameless registration systems are spreading.

OBJECTIVE

To investigate the accuracy and effectiveness of a new stereotactic biopsy procedure.

METHODS

Observational, retrospective analysis of consecutive robot-assisted stereotactic biopsies using the Neurolocate (Renishaw) frameless registration system and intraoperative O-Arm (Medtronic) performed at a single institution in adults (2019-2021) and comparison with a historical series from the same institution (2006-2016) not using the Neurolocate nor the O-Arm.

RESULTS

In 100 patients (55% men), 6.2 ± 2.5 (1-14) biopsy samples were obtained at 1.7 ± 0.7 (1-3) biopsy sites. An histomolecular diagnosis was obtained in 96% of cases. The mean duration of the procedure was 59.0 ± 22.3 min. The mean distance between the planned and the actual target was 0.7 ± 0.7 mm. On systematic postoperative computed tomography scans, a hemorrhage ≥10 mm was observed in 8 cases (8%) while pneumocephalus was distant from the biopsy site in 76%. A Karnofsky Performance Status score decrease ≥20 points postoperatively was observed in 4%. The average dose length product was 159.7 ± 63.4 mGy cm. Compared with the historical neurosurgical procedure, this new procedure had similar diagnostic yield (96 vs 98.7%; P = .111) and rate of postoperative disability (4.0 vs 4.2%, P = .914) but was shorter (57.8 ± 22.9 vs 77.8 ± 20.9 min; P < .001) despite older patients.

CONCLUSION

Robot-assisted stereotactic biopsy using the Neurolocate frameless registration system and intraoperative O-Arm is a safe and effective neurosurgical procedure. The accuracy of this robot-assisted surgery supports its effectiveness for daily use in stereotactic neurosurgery.

A Comparison of the Safety, Efficacy, and Accuracy of Frame-Based versus Remebot Robot-Assisted Stereotactic Systems for Biopsy of Brainstem Tumors

BACKGROUND

Brainstem tumors are rare and extremely heterogeneous and present significant challenges in surgical treatment. Thus, biopsies often set the foundation for the diagnosis of brainstem tumors. Multimodal, image-guided, robot-assisted frameless stereotactic biopsies are increasingly popular in neurosurgery centers. This study aimed to compare the safety, efficacy, and duration of the Remebot robot-assisted (Remebot) frameless brainstem tumor biopsy versus those of frame-based stereotactic biopsy.

METHOD

A retrospective analysis of 33 patients with brainstem tumors who underwent stereotactic brainstem biopsies in the department of neurosurgery from January 2016 to January 2021 was conducted. The patients were divided into two groups: the Remebot group (n = 22) and the frame-based group (n = 11). The clinical characteristics, trajectory strategy, duration of procedure, diagnostic yielding, histopathological diagnosis, and postoperative complications were retrospectively analyzed and compared between the groups.

RESULTS

More pediatric patients performed Remebot frameless brainstem tumor biopsy than frame-based biopsy, with a mean age of 17.3 ± 18.7 vs. 32.8 ± 17.1 (p = 0.027). The diagnostic yield had no significant difference in the two groups, with the diagnostic yield of frame-based biopsy and Remebot frameless brain biopsy being 90.9% and 95.5%, respectively. The time of the total process was 124.5 min for the frame-based biopsy and 84.7 min for the Remebot frameless brain biopsy (p < 0.001). There were no significant differences with respect to the occurrence of complication or the duration of the operation between the two groups.

CONCLUSION

Remebot frameless stereotactic brainstem biopsy is as safe and efficacious as frame-based stereotactic biopsy. However, Remebot frameless biopsy can reduce the total duration of the procedure and has better application in young pediatric patients. Remebot frameless stereotactic biopsies can be a better option towards the safe and efficient treatment of brainstem tumors.

A New Noninvasive Frameless Registration System for Stereotactic Cranial Biopsy: A Technical Note

BACKGROUND

Although frame-based stereotactic biopsy is still considered the gold standard for brain biopsies, frameless robot-assisted stereotactic systems are now able to provide an equal level of safety and accuracy. However, both systems suffer from a lack of efficiency of the operative workflow.

OBJECTIVE

To describe the technique of a new frameless and noninvasive registration tool Neurolocate (Renishaw). This tool, combined with an intraoperative cone-beam computed tomography imaging system like O-ARM (Medtronic), might facilitate the achievement and workflow of robot-assisted stereotactic intracranial biopsies.

METHODS

Neurolocate is a 3-dimensional fiducial tool fixed directly on the Neuromate (Renishaw) robot arm. It consists of 5 radio-opaque spherical fiducials, whose geometry is constant. This tool made it possible to carry out the coregistration then the biopsy in the same operating time, following a five-step procedure described here. We retrospectively extracted selected preliminary results from our initial experience.

RESULTS

Over 1 year, 23 consecutive adult patients were biopsied with Neurolocate in our center. The mean overall operative time, from patient's installation to skin closure, was 97 minutes ± 27 (SD). The entire procedure took place in a single location unit (operating room), which facilitated workflow and surgical planning. No invasive gesture was performed outside of the operating time.

CONCLUSION

Neurolocate is a new frameless and noninvasive registration tool that could improve workflow and flexibility for operating room management and surgical planning. It may also increase the comfort of patients undergoing robot-assisted intracranial stereotactic biopsies. The accuracy and safety profile should be addressed in specific studies.

Frameless Robotic-Assisted Biopsy of Pediatric Brainstem Lesions: A Systematic Review and Meta-Analysis of Efficacy and Safety

BACKGROUND

Pediatric brainstem lesions are diagnoses that require tissue sampling to advance our understanding of them and their management. Frameless, robot-assisted biopsy of these lesions has emerged as a novel, viable biopsy approach. Correspondingly, the aim of this study was to quantitively and qualitatively summarize the contemporary literature regarding the likelihood of achieving tumor diagnosis and experiencing any postoperative complications.

METHODS

Searches of 7 electronic databases from inception to September 2022 were conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Articles were screened against prespecified criteria. Outcomes were pooled by random-effects meta-analyses of proportions where possible.

RESULTS

A total of 8 cohort studies satisfied all criteria. They described 99 pediatric patients with brainstem lesions in whom frameless, robot-assisted biopsy was involved in their work-up. There were 62 (63%) male and 37 (37%) female patients with a median age of 9 years at time of biopsy. Overall, all patients had sufficient tissue obtained by initial biopsy for evaluation. Pooled estimate of achieving tumor diagnosis was 100% (95% confidence interval [CI] 97%-100%) across all studies with a high degree of certainty. Across all studies, there were no cases of procedure-related mortality. The pooled estimates of transient and permanent complications after biopsy were 10% (95% CI 4%-19%) and 0% (95% CI 0%-2%), respectively, of very low and low degrees of certainty each.

CONCLUSIONS

The contemporary metadata demonstrates the frameless, robot-assisted biopsy of pediatric brainstem lesions is both effective and safe when performed in an experienced setting. Further research is needed to augment robot and automated technologies into workup algorithms.

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

Stereotactic frame-based brain tumor biopsy (SFB) is a potent diagnostic tool considering its minimal invasiveness, though its diagnostic power and safety for brainstem lesions remain to be discussed. Here, we aimed to examine the usefulness of SFB for brainstem tumors. Twenty-two patients with brainstem tumors underwent 23 SFBs at our institution during 2002–2021. We retrospectively analyzed patient characteristics, tumor pathology, surgical procedures, and outcomes, including surgery-related complications and the diagnostic value. Seven (32%) tumors were located from the midbrain to the pons, eleven (50%) in the pons only, and four (18%) from the pons to the medulla oblongata. The target lesions were in the middle cerebellar peduncles in sixteen procedures (70%), the cerebellum in four (17%), the inferior cerebellar peduncles in two (9%), and the superior cerebellar peduncles in one (4%). A definitive diagnosis was made in 21 patients (95%) at the first SFB. The diagnoses were glioma in seventeen (77%) cases, primary central nervous system lymphoma in four (18%), and a metastatic brain tumor in one (5%). The postoperative complications (cranial nerve palsy in three [13%] cases, ataxia in one [4%]) were all transient. SFB for brainstem tumors yields a high diagnostic rate with a low risk of morbidity.