Factors affecting diagnostic yield in stereotactic biopsy for brain lesions: a 5-year single-center series

Analysis of factors influencing diagnostic yield and target point error in robot-assisted stereotactic brain biopsy: a single-center experience

Robot-assisted brain tissue biopsy plays a pivotal role in diagnosing complex intracranial lesions. This study retrospectively examines the factors influencing the diagnostic yield and target point error (TPE) in frameless intracranial stereotactic brain biopsy using the Remebot surgical robot. The clinical data of 584 patients who underwent robot-assisted stereotactic brain biopsy at Xuanwu Hospital, China, between April 2019 and December 2023 were analysed. The data collected included histopathological diagnosis results and TPEs. Univariate and multivariate logistic regression analyses were performed to explore the factors influencing diagnostic yield. Multivariate linear regression was used to analyse the factors influencing TPE. MRI enhancement was an independent factor influencing the diagnostic yield, with enhanced lesions showing a higher rate (OR = 0.017, 95% CI: 0.007-0.041; P < 0.001). Larger target volumes were also correlated with higher positivity rates (OR = 1.484, 95% CI: 1.259-1.751; P < 0.001). Smaller TPEs were associated with higher positivity rates (OR = 0.103, 95% CI: 0.045-0.233; P < 0.001). Larger entry point tangential angles resulted in smaller TPEs (b = -0.093, t = -38.034, P < 0.001), and supratentorial locations had smaller errors than infratentorial locations did (b = -0.514, t = -9.182, P < 0.001). Markpoint registration was more accurate than facial laser scanning registration was (b = -0.064, t = -2.484, P = 0.013). Robot-assisted frameless stereotactic biopsy is an accurate and safe method. It is crucial to strictly adhere to the surgical indications, such as selecting cases with significant imaging enhancement. The puncture path should be planned rationally, with the biopsy needle inserted as vertically as possible to the cranial surface. A more suitable registration method should be chosen, and if higher precision is required, marked point registration should be used. This will ensure the accuracy of the target and achieve a higher diagnostic yield.

Intraoperative ex-vivo epifluorescent diagnostics of stereotactic brain biopsies using EndoScell scanner: diagnostic accuracy study

Brain biopsy is commonly employed for the histological diagnosis of complex intracranial diseases. To improve the positive diagnostic rate, the precision of intraoperative tissue sampling is critical. This study evaluated the accuracy of fluorescence imaging technology in rapidly distinguishing tumours from nontumour tissue during surgery, thus providing real-time feedback to surgeons and optimizing the surgical workflow. Biopsy samples from 65 patients were selected for this study. The lesion tissues were sequentially stained with sodium fluorescein and methylene blue, followed by fluorescence imaging via a handheld EndoScell scanner under an intraoperative cellular microscope. Frozen section examinations and haematoxylin-eosin (HE) staining were performed on the same lesion tissue by the pathology department. The time required for fluorescence imaging and pathology of frozen sections was recorded. The results of fluorescence imaging (whether the tissue was a tumour or nontumour tissue) and frozen pathology (whether the tissue was a tumour or nontumour tissue) were also recorded. The HE staining results were used as the final gold standard for diagnosis. The sensitivity, specificity, area under the curve (AUC), Kappa consistency test, and diagnostic efficiency of both methods were calculated. Lesion tissue and diagnostic results were successfully obtained from all 65 patients. When HE-stained histopathology was used as the gold standard, the sensitivity of fluorescence imaging was 100% (95% CI: 0.917-1.000), and the specificity was 63.6% (95% CI: 0.316-0.876). In comparison, the sensitivity of frozen section pathology was 88.9% (95% CI: 0.767-0.954), and the specificity was 100% (95% CI: 0.679-1.000). Both methods demonstrated high diagnostic accuracy. ROC curve analysis revealed that the AUCs for fluorescence imaging and frozen pathology were 0.818 and 0.944, respectively, with no significant difference observed in diagnostic performance (Z = 1.597, P > 0.05). Kappa consistency tests indicated that the Kappa value for frozen pathology compared with HE staining was 0.730 (P < 0.001); for fluorescence imaging compared with HE staining, the Kappa value was 0.744 (P < 0.001), thus demonstrating strong agreement with the HE staining results for both methods. In terms of time efficiency, fluorescence imaging was significantly faster than frozen section pathology [6 (4, 7) min vs. 48 (46, 55) min, Z=-9.856, P < 0.001], thus showing a clear advantage regarding time efficiency for fluorescence imaging. Intraoperative fluorescence imaging via an EndoScell scanner, which represents a novel method for histopathological diagnosis, has high diagnostic accuracy and efficiency. This method provides real-time guidance for tissue sampling strategies in brain biopsy, thereby improving the positive diagnostic rate and reducing surgical risk.

Improving Diagnostic Yield and Accuracy of Stereotactic Biopsies through Changes in Practice and Techniques: An 8-Year Single-Center Comparative Study

Background  Stereotactic biopsies are used to aid neurosurgeons in clinching the diagnosis of intracranial lesions that are difficult to access surgically. A published study of stereotactic biopsies in our center demonstrated a diagnostic yield of only 76% for biopsies from the year 2014 to 2019. A set of criteria/prerequisites was applied to increase yield. Objective  The aim of the study was to identify the improvement in accuracy and yield after implementation of a set of criteria/prerequisites. Materials and Methods  This was a retrospective and prospective analysis of all patients who underwent stereotactic biopsies from the year 2014 to 2022. This study was conducted at Sarawak General Hospital, Malaysia. A set of stereotactic criteria/prerequisites was introduced since 2020, which include preoperative careful, meticulous trajectory planning and target selection, regular checking and maintenance of equipment, larger burr holes, and good sampling techniques. Results  A total of 83 patients underwent stereotactic biopsies from the year 2014 to 2022. Frameless and frame-based methods were used for 45 (54%) and 38 (46%) patients, respectively. The overall diagnostic yield of all biopsies was 84%. Fifty patients underwent stereotactic biopsies prior to implementation of good practice guidelines in 2020 with a positive histopathological yield and accuracy of 76 and 88%, respectively. Thirty-three biopsies done postimplementation demonstrated a yield and accuracy of 97% ( p  < 0.05). There was also a shift of preference toward frame-based methods after 2019, with 85% of these biopsies being frame based. Conclusion  This comparative study shows that adherence to specific stereotactic biopsy guidelines and techniques introduced in our center has successfully improved our biopsy yield and accuracy.

Comparison of diagnostic yields, operative times, and post-operative hemorrhage between twist drill versus burr hole craniotomy approaches for stereotactic needle brain biopsy

Stereotactic frameless needle brain biopsy is a common neurosurgical procedure performed via twist drill or open burr hole approaches. We aim to compare diagnostic yields and surgical outcomes to delineate the safety and efficacy of both approaches. A retrospective database of all stereotactic needle biopsy procedures performed at a single institution over 30 months was conglomerated. Demographics, medical comorbidities, operative details/complications, immediate post-operative imaging, and pathology were abstracted. Two hundred and twenty-five needle biopsies were identified, of which 165 (73.3%) were open, and 60 (26.7%) were twist drill. Diagnostic pathology yield rates between open (84.8%) and twist drill (93.3%) approaches were similar (p = 0.15), with a median of 4 cores taken in each (p = 0.30). Diagnostic tissue yields with an intra-operative pause for pathology confirmation was 90.4% compared to 79.1% without pause (p = 0.036, OR 2.49). Median operative times for open versus twist drill procedures were 68.0 min (IQR 49-83) versus 35.5 min (IQR 26-54), respectively (Wilcoxon p < 0.001), which remained significant after controlling for awaiting intraoperative pathology using bivariable linear modeling (p < 0.001). Intraoperative bleeding through the needle cannula was noted in 22 patients (9.8%), including eight twist drill (13.3%) and 14 open needles (8.5%). Of 197 cases (87.6%) with post-operative cranial imaging (CT/MRI), 90 (45.7%) demonstrated some degree of post-operative hemorrhage characterized as superficial (n = 10, 11.1%), deep/intralesional (n = 64, 71.1%) bleeding, or both (n = 16, 17.9%). Bleeding rates between open (46.7%) and twist drill (43.3%) approaches were similar (p = 0.78). Post-operative clinical decline or neurological change was noted in 9 patients (4.0%), including one twist drill (1.7%) and eight open needles (4.8%), among which 7 (78%) had deep blood products identified on post-operative imaging. Stereotactic needle biopsy via twist drill approach has similar diagnostic yield rates, asymptomatic bleeding rates, and post-operative complications with significantly shorter operative time and smaller incision size than conventional open burr hole needle biopsy. Using intra-operative frozen histopathology for presumed sufficient diagnostic tissue may improve final pathologic diagnostic rates regardless of approach technique.

Sodium fluorescein and 5-aminolevulinic acid fluorescence- guided biopsy in brain lesions: a systematic review and meta-analysis

PURPOSE

Stereotactic brain biopsies are highly efficient for diagnosing intracerebral pathologies, particularly when surgical resection is infeasible. Fluorescence-based agents such as 5-aminolevulinic acid (5-ALA) and fluorescein sodium (NaFl) can enhance diagnostic accuracy and safety, improving the visualization of lesional tissues. This meta-analysis aimed to evaluate their effect on diagnostic yield and complication rates of brain biopsies.

METHODS

This study adhered to Cochrane and PRISMA guidelines. We assessed studies for diagnostic yield and complication rates. Data was analyzed using a random-effects model in RStudio. Diagnostic accuracy measures such as sensitivity and predictive values were calculated based on fluorescence visibility in biopsy samples.

RESULTS

Thirty-two non-randomized studies were included, comprising 947 patients, with a mean age ranging from 37 to 77 years, and a mean sample number ranging from 1 to 15 specimens. Diagnostic yields were high: 93% for NaFl and 96% for 5-ALA. Major complications occurred in 3% of procedures with both agents, while minor complications were reported in 7% and 5% with NaFl and 5-ALA respectively. The Negative-predictive-value (NPV) of 5-ALA and NaFl were 8-11% and 60-80% respectively. NaFl demonstrates higher sensitivity and specificity at 84% and 100% compared to 5-ALA's 66%. and 85% respectively.

CONCLUSION

5-ALA and NaFl provide high diagnostic yields with acceptable safety profiles in stereotactic biopsies. NaFl showed higher sensitivity and specificity. NaFl outperforms 5ALA in terms of NPV making it more efficient for small lesions near eloquent regions or major blood vessels. The significance of these findings can be further ascertained through randomized trials.

Rapid tumor DNA analysis of cerebrospinal fluid accelerates treatment of central nervous system lymphoma

ABSTRACT

Delays and risks associated with neurosurgical biopsies preclude timely diagnosis and treatment of central nervous system (CNS) lymphoma and other CNS neoplasms. We prospectively integrated targeted rapid genotyping of cerebrospinal fluid (CSF) into the evaluation of 70 patients with CNS lesions of unknown cause. Participants underwent genotyping of CSF-derived DNA using a quantitative polymerase chain reaction-based approach for parallel detection of single-nucleotide variants in the MYD88, TERT promoter, IDH1, IDH2, BRAF, and H3F3A genes within 80 minutes of sample acquisition. Canonical mutations were detected in 42% of patients with neoplasms, including cases of primary and secondary CNS lymphoma, glioblastoma, IDH-mutant brainstem glioma, and H3K27M-mutant diffuse midline glioma. Genotyping results eliminated the need for surgical biopsies in 7 of 33 cases (21.2%) of newly diagnosed neoplasms, resulting in significantly accelerated initiation of disease-directed treatment (median, 3 vs 12 days; P = .027). This assay was then implemented in a Clinical Laboratory Improvement Amendments environment, with 2-day median turnaround for diagnosis of CNS lymphoma from 66 patients across 4 clinical sites. Our study prospectively demonstrates that targeted rapid CSF genotyping influences oncologic management for suspected CNS tumors.

Diagnostic yield of postmortem brain examination following premortem brain biopsy for neoplastic and nonneoplastic disease

Medical autopsies have decreased in frequency due in part to advances in radiological techniques and increased availability of molecular and other ancillary testing. However, premortem diagnosis of CNS disease remains challenging; while ∼90% of brain tumor biopsies are diagnostic, only 20%-70% of biopsies for presumed nonneoplastic disease result in a specific diagnosis. The added benefits of performing an autopsy following surgical brain biopsy are not well defined. A retrospective analysis was performed of patients who underwent brain biopsy and autopsy at Brigham and Women's Hospital from 2003 to 2022. A total of 135 cases were identified, including 95 (70%) patients with primary CNS neoplasms, 16 (12%) with metastatic tumors, and 24 (18%) with nonneoplastic neurological disease. Diagnostic concordance between biopsy and autopsy diagnosis was excellent both for primary CNS neoplasms (98%) and metastatic tumors (94%). Conversely, patients with nonneoplastic disease received definitive premortem diagnoses in 7/24 (29%) cases. Five (21%) additional patients received conclusive diagnoses following autopsy; 8 (33%) received a more specific differential diagnosis compared to the biopsy. Overall, autopsy confirmed premortem diagnoses or provided new diagnostic information in 131/135 (97%) cases, highlighting the value in performing postmortem brain examination in patients with both neoplastic and nonneoplastic diseases.

Novel application of robot-guided stereotactic technique on biopsy diagnosis of intracranial lesions

Introduction

This study was performed to examine whether there is a link between the application of three types of robot-guided stereotactic biopsy techniques and the diagnostic rate of intracranial lesion biopsy.

Methods

The study involved 407 patients who underwent robot-guided stereotactic intracranial lesion biopsy at Xuanwu Hospital of Capital Medical University from January 2019 to December 2021. Age, sex, lesion characteristics, lesion distribution, surgical method, and target path depth were assessed for their impact on the biopsy diagnostic rate.

Results

The patients' mean age was 42.1 years (range, 6 months-82 years). All patients underwent robot-assisted stereotactic brain biopsy using one of three different systems: a ROSA robotic system (n=35), the CAS-R-2 (n=65), or the REMEBOT domestic robotic system (n=307). No significant difference was found in the diagnostic rate of positive histopathological findings or the mean time of surgery among the three biopsy modalities. The diagnostic rate was 93.86%. Multiple linear regression analysis showed that age, sex, and biopsy modality did not affect the diagnostic rate n>0.05), whereas enhancing lesions and smaller-volume lesions (≤l cm3) were significantly correlated with the diagnostic rate (p = 0.01). Lesions located in the suprasellar and pineal regions were significantly associated with the negative diagnostic rate (p<0.05).

Conclusion

The presence of enhancing lesions, lesion location, and lesion volume significantly affected the diagnostic rate of brain biopsy. Age, sex, lesion depth, and biopsy modality did not significantly affect the diagnostic rate. All three procedures had high safety and effectiveness.