Safety and therapeutic impact of stereotactic biopsy in very elderly patients with brain tumors

J Neurosurg 143:194–203, 2025

Stereotactic brain biopsy in patients aged ≥80 is safe, with high diagnostic yield (96.2%) and low persistent neurological deficit (1.9%). Prebiopsy Karnofsky Performance Status ≥70% predicts full adjuvant therapy and longer survival. Biopsy findings frequently alter management, supporting its use in very elderly brain tumor patients.

• Stereotactic brain biopsy in patients aged ≥80 years is safe and has a high diagnostic yield (96.2%).

• Symptomatic complication rate was 6.2%, with persistent neurological deficit in 1.9% and a procedure-related mortality of 0.5%.

• The biopsy changed the suspected diagnosis in 11.1% of cases, influencing patient management.

• 80.7% of patients received adjuvant treatment after biopsy; 19.3% received palliative care.

• A Karnofsky Performance Status (KPS) score ≥70% was the only significant predictor for receiving full adjuvant therapy and longer overall survival (OS).

• Median OS after biopsy was 5.6 months; longer in patients with PCNSL or methylated MGMT promoter in glioma.

• No significant increase in complications was seen with deep-seated tumors, anticoagulant use, or advanced age (≥85 or ≥90 years).

• The study supports considering biopsy for very elderly patients when technically feasible and patient condition is good.

To scan or not to scan? A retrospective cohort study analysing the efficacy of routine post‑operative CT after brain biopsy

Acta Neurochirurgica (2024) 166:288

Postoperative management following elective cranial surgery, particularly after biopsy procedures, varies significantly across neurosurgical centres. Routine postoperative head CT scans, traditionally performed to detect complications such as intracranial bleeding or cerebral oedema, lack substantial evidence supporting their necessity.

Methods This study is a retrospective cohort analysis conducted at a regional neurosurgical department of 236 patients who underwent brain biopsies between 2018 and 2022. Patient data, including demographics, surgical details, and postoperative outcomes, were collected and analysed. The outcomes investigated were the incidence and impact of postoperative CT scans on time to discharge, management changes, and the influence of preoperative anticoagulation.

Results Out of 236 patients, 205 (86.86%) underwent postoperative CT scans. There was no significant relationship between postoperative hematoma, as detected on a CT scan, and neurological deficit (p = 0.443), or between preoperative anticoagulation and postoperative bleeding on CT scans (p = 0.464). Patients who had postoperative CT scans had a significantly longer length of stay (LOS) compared to those who did not (p < 0.001). Intraoperative bleeding was a predictor of hematoma on postoperative CT (p = 0.017) but not of postoperative neurological deficit. The routine postoperative CT scan showed limited predictive value for symptomatic deficits, with a positive predictive value of 6.67% and a negative predictive value of 96.88%.

Conclusions Routine postoperative CT scans after brain biopsies do not significantly impact management or improve patient outcomes but are associated with longer hospital stays. CT scans should be reserved for patients showing clinical signs of complications rather than used as a routine procedure after a brain biopsy.

Surgical Characteristics of Intracranial Biopsy Using a Frameless Stereotactic Robotic Platform: A Single-Center Experience

Operative Neurosurgery 26:502–510, 2024

Cranial robotics are a burgeoning field of neurosurgery. To date, all cranial robotic systems described have been computerized, arm-based instruments that take up significant space in the operating room. The Medtronic Stealth Autoguide robot has a smaller operating room footprint and offers multiaxial, frame-based surgical targeting. The authors set out to define the surgical characteristics of a novel robotic platform for brain biopsy in a large patient cohort.

METHODS: Patients who underwent stereotactic biopsy using the Stealth Autoguide cranial robotic platform from July 2020 to March 2023 were included in this study. Clinical, surgical, and histological data were collected and analyzed.

RESULTS: Ninety-six consecutive patients (50 female, 46 male) were included. The mean age at biopsy was 53.7 ± 18.0 years. The mean target depth was 68.2 ± 15.3 mm. The biopsy diagnostic tissue acquisition rate was 100%. The mean time from incision to biopsy tissue acquisition was 15.4 ± 9.9 minutes. Target lesions were located throughout the brain: in the frontal

lobe (n = 32, 33.3%), parietal lobe (n = 21, 21.9%), temporal lobe (n = 22, 22.9%), deep brain nuclei/thalamus (n = 13, 13.5%),

cerebellum (n = 7, 7.3%), and brainstem (n = 1, 1.0%). Most cases were gliomas (n = 75, 78.2%). Patients were discharged home on postoperative day 0 or 1 in 62.5% of cases. A total of 7 patients developed postoperative complications (7.2%).

CONCLUSION: This cranial robotic platform can be used for efficient, safe, and accurate cranial biopsies that allow for reliable diagnosis of intracranial pathology in a minimally invasive setting.

Associations of intracranial pressure with brain biopsy, radiological findings, and shunt surgery outcome in patients with suspected idiopathic normal pressure hydrocephalus

Acta Neurochir (2017) 159: 51-61

It remains unclear how intracranial pressure (ICP) measures are associated with brain biopsies and radiological markers. Here, we aim to investigate associations between ICP and radiological findings, brain biopsies, and shunt surgery outcome in patients with suspected idiopathic normal pressure hydrocephalus (iNPH).

Method

In this study, we retrospectively analyzed data from 73 patients admitted with suspected iNPH to Kuopio University Hospital. Of these patients, 71% underwent shunt surgery. The NPH registry included data on clinical and radiological examinations, 24-h intraventricular pressure monitoring, and frontal cortical biopsy.

Results

The mean ICP and mean ICP pulse wave amplitude were not associated with the shunt response. Aggregations of Alzheimer’s disease (AD)-related proteins (amyloid-β, hyperphosphorylated tau) in frontal cortical biopsies were associated with a poor shunt response (P = 0.014). High mean ICP was associated with Evans’ index (EI; P = 0.025), disproportional sylvian and suprasylvian subarachnoid spaces (P = 0.014), and focally dilated sulci (P = 0.047). Interestingly, a high pulse wave amplitude was associated with AD-related biopsy findings (P = 0.032), but the mean ICP was not associated with the brain biopsy. The ICP was not associated with medial temporal lobe atrophy, temporal horn widths, or white matter changes. ICP B waves were associated with less atrophy of the medial temporal lobe (P = 0.018) and more severe disproportionality between the sylvian and suprasylvian subarachnoid spaces (P = 0.001).

Conclusions

The EI and disproportional sylvian and suprasylvian subarachnoid spaces were associated with mean ICP. Disproportionality was also associated with ICP B waves. These associations, although rather weak, with elevated ICP in 24-h measurements, support their value in iNPH diagnostics and suggest that these radiological markers are potentially related to the pathogenesis of iNPH. Interestingly, our results suggested that elevated pulse wave amplitude might be associated with brain amyloid accumulation.

Diagnostic Value and Safety of Brain Biopsy in Patients With Cryptogenic Neurological Disease: A Systematic Review and Meta-analysis of 831 Cases

Brain_biopsy_under_stereotaxy

Neurosurgery 77:283–295, 2015

The role of brain biopsy in patients with cryptogenic neurological disease is uncertain.

OBJECTIVE: To determine the risks and benefits of diagnostic brain biopsy for nonneoplastic indications in immunocompetent patients.

METHODS: Appropriate studies were identified by searching electronic databases.

RESULTS: We screened 3645 abstracts and included 20 studies with a total of 831 patients. Indications for biopsy were: (1a) severe neurological disease of unknown etiology in adults (n = 7) and (1b) in children (n = 2); (2) suspected primary angiitis of the central nervous system (PACNS) (n = 3); (3) chronic meningitis of unknown cause (n = 3); (4) atypical dementia (n = 4); and (5) nonneoplastic disease (n = 1). Diagnostic success rates calculated for subgroups were 51.3% (34.5-68.1) for 1a, 53.8% (42.9-64.5) for 1b, 74.7% (64.0-84.1) for 2, 30.3% (17.2-45.4) for 3, and 60.8% (41.2-78.8) for 4. Clinical impact rates were 30.5% (13.6-50.6) for 1a (n = 6), 67.1% (42.8-87.3) for 1b (n = 2), 8.3% (2.3-20.0) for 3 (n = 1), and 14.2% (6.5-24.3) for 4 (n = 2). Lymphoma (n = 32) and Creutzfeldt-Jakob disease (n = 30) were the most common diagnoses on the final histopathology reports of positive brain biopsies in 1a. In 1b, encephalitis (n = 7), PACNS (n = 6), and demyelination (n = 6) were the most common. The odds ratio for achieving a diagnostic biopsy when there was a radiological target was 3.70 (P = .014, 95% confidence interval, 1.31-10.42).

CONCLUSION: Brain biopsy in cryptogenic neurological disease was associated with the highest diagnostic yield in patients with suspected PACNS. The greatest clinical impact was seen in children with cryptogenic neurological disease. The presence of a radiological target was associated with a higher diagnostic yield.

Frameless image-guided stereotaxy with real-time visual feedback for brain biopsy

Acta Neurochir (2012) 154:1663–1667 DOI 10.1007/s00701-012-1425-y

Frame-based stereotaxy remains the “gold standard” for cerebral biopsies and functional neurosurgery though new frameless stereotactic systems are evolving continually. As the technique of frameless stereotaxy gains increasing acceptance among neurosurgeons, this study assesses the feasibility of a system for frameless imageguided stereotaxy.

Methods All patients biopsied for intracranial lesions between February 2007 and August 2010 using the BrainLAB VarioGuide frameless stereotactic system were evaluated prospectively. Prior to surgery, patients underwent magnetic resonance (MR) imaging; additionally, fluoroethyl-tyrosine (FET)-positron emission tomography (PET) images were acquired and fused to MR images in selected cases. Biopsy trajectory length, lesion volume, procedure duration, and diagnostic yield were assessed.

Results Ninety-six diagnostic biopsies in 91 patients were evaluated. Lesion volume ranged from 0.17 to 121.8 cm3; trajectory length from 25.3 to 101.9 mm. Diagnostic yield was 93.8%. Mean operation time from skin incision to wound closure was 42 min; in the operating room, it was 99 min.

Conclusions Clinical experience indicates VarioGuide to be safe and accurate. Reachable range of lesion localisation appears to be comparable to a frame-based stereotaxy system. Operation times are brief. The unique design of this frameless stereotactic system allows real-time visual feedback of needle positioning.