Neuronavigation-assisted trajectory planning for deep brain biopsy with susceptibility-weighted imaging

Development and Application of the Portable Electromagnetic Navigation for Neurosurgery

BACKGROUND AND OBJECTIVE

Electromagnetic navigation technology has demonstrated significant potential in enhancing the accuracy and safety of neurosurgical procedures. However, traditional electromagnetic navigation systems face challenges such as high equipment costs, complex operation, bulky size, and insufficient anti-interference performance. To address these limitations, our study developed and validated a novel portable electromagnetic neuronavigation system designed to improve the precision, accessibility, and clinical applicability of electromagnetic navigation technology in cranial surgery.

METHODS

The software and hardware architecture of a portable neural magnetic navigation system was designed. The key technologies of the system were analysed, including electromagnetic positioning algorithms, miniaturized sensor design, optimization of electromagnetic positioning and navigation algorithms, anti-interference signal processing methods, and fast three-dimensional reconstruction algorithms. A prototype was developed, and its accuracy was tested. Finally, a preliminary clinical application evaluation was conducted.

RESULTS

This study successfully developed a comprehensive portable electromagnetic neuronavigation system capable of achieving preoperative planning, intraoperative real-time positioning and navigation, and postoperative evaluation of navigation outcomes. Through rigorous collaborative testing of the system's software and hardware, the accuracy of electromagnetic neuronavigation has been validated to meet clinical requirements.

CONCLUSIONS

This study developed a portable neuroelectromagnetic navigation system and validated its effectiveness and safety through rigorous model testing and preliminary clinical applications. The system is characterized by its compact size, high precision, excellent portability, and user-friendly operation, making it highly valuable for promoting navigation technology and advancing the precision and minimally invasive nature of neurosurgical procedures.

Automatic Path-Planning Techniques for Minimally Invasive Stereotactic Neurosurgical Procedures-A Systematic Review

This review systematically examines the recent research from the past decade on diverse path-planning algorithms tailored for stereotactic neurosurgery applications. Our comprehensive investigation involved a thorough search of scholarly papers from Google Scholar, PubMed, IEEE Xplore, and Scopus, utilizing stringent inclusion and exclusion criteria. The screening and selection process was meticulously conducted by a multidisciplinary team comprising three medical students, robotic experts with specialized knowledge in path-planning techniques and medical robotics, and a board-certified neurosurgeon. Each selected paper was reviewed in detail, and the findings were synthesized and reported in this review. The paper is organized around three different types of intervention tools: straight needles, steerable needles, and concentric tube robots. We provide an in-depth analysis of various path-planning algorithms applicable to both single and multi-target scenarios. Multi-target planning techniques are only discussed for straight tools as there is no published work on multi-target planning for steerable needles and concentric tube robots. Additionally, we discuss the imaging modalities employed, the critical anatomical structures considered during path planning, and the current status of research regarding its translation to clinical human studies. To the best of our knowledge and as a conclusion from this systematic review, this is the first review paper published in the last decade that reports various path-planning techniques for different types of tools for minimally invasive neurosurgical applications. Furthermore, this review outlines future trends and identifies existing technology gaps within the field. By highlighting these aspects, we aim to provide a comprehensive overview that can guide future research and development in path planning for stereotactic neurosurgery, ultimately contributing to the advancement of safer and more effective neurosurgical procedures.

Safety and efficacy of frameless stereotactic robot-assisted intraparenchymal brain lesion biopsies versus image-guided biopsies: a bicentric comparative study

PURPOSE

User-friendly robotic assistance and image-guided tools have been developed in the past decades for intraparenchymal brain lesion biopsy. These two methods are gradually becoming well accepted and are performed at the discretion of the neurosurgical teams. However, only a few data comparing their effectiveness and safety are available.

METHODS

Population-based parallel cohorts were followed from two French university hospitals with different surgical methods and defined geographical catchment regions (September 2019 to September 2022). In center A, frameless robot-assisted stereotactic intraparenchymal brain lesion biopsies were performed, while image-guided intraparenchymal brain lesion biopsies were performed in center B. Pre-and postoperative clinical, radiological, and histomolecular features were retrospectively collected and compared.

RESULTS

Two hundred fifty patients were included: 131 frameless robot-assisted stereotactic intraparenchymal brain lesion biopsies in center A and 119 image-guided biopsies in center B. The clinical, radiological, and histomolecular features were comparable between the two groups. The diagnostic yield (96.2% and 95.8% respectively; p = 1.000) and the overall postoperative complications rates (13% and 14%, respectively; p = 0.880) did not differ between the two groups. The mean duration of the surgical procedure was longer in the robot-assisted group (61.9 ± 25.3 min, range 23-150) than in the image-guided group (47.4 ± 11.8 min, range 25-81, p < 0.001). In the subgroup of patients with anticoagulant and/or antiplatelet therapy administered preoperatively, the intracerebral hemorrhage > 10 mm on postoperative CT scan was higher in the image-guided group (36.8%) than in the robot-assisted group (5%, p < 0.001).

CONCLUSION

In our bicentric comparative study, robot-assisted stereotactic and image-guided biopsies have two main differences (shorter time but more frequent postoperative hematoma for image-guided biopsies); however, both techniques are demonstrated to be safe and efficient.

When to discharge patients following a neuronavigation-assisted brain biopsy for supratentorial lesion? A single-center experience

OBJECTIVE

Most brain biopsies are performed using the frame-based stereotactic technique and several studies describe the time taken and rate of complications, often allowing an early discharge. In comparison, neuronavigation-assisted biopsies are performed under general anesthesia and their complications have been poorly described. We examined the complication rate and determined which patients will worsen clinically.

METHODS

All adults who underwent a neuronavigation-assisted brain biopsy for a supratentorial lesion from Jan, 2015, to Jan, 2021, in the Neurosurgical Department of the University Hospital Center of Bordeaux, France, were analyzed retrospectively in accordance with the Strengthening the Reporting of Observational studies in Epidemiology (STROBE) statement. The primary outcome of interest was short-term (7 days) clinical deterioration. The secondary outcome of interest was the complication rate.

RESULTS

The study included 240 patients. The median postoperative Glasgow score was 15. Thirty patients (12.6 %) showed acute postoperative clinical worsening, including 14 (5.8 %) with permanent neurological worsening. The median delay was 22 h after the intervention. We examined several clinical combinations that allowed early postoperative discharge. A preoperative Glasgow prognostic score of 15, Charlson Comorbidity Index ≤ 3, preoperative World Health Organization Performance Status ≤ 1, and no preoperative anticoagulation or antiplatelet treatment predicted postoperative worsening (negative predictive value, 96.3 %).

CONCLUSION

Optical neuronavigation-assisted brain biopsies might require longer postoperative observation than frame-based biopsies. Based on strict preoperative clinical criteria, we consider to plan postoperative observation for 24 h a sufficient hospital stay for patients who undergo these brain biopsies.

High intratumoral susceptibility signal grade on susceptibility-weighted imaging: a risk factor for hemorrhage after stereotactic biopsy

OBJECTIVE

This study aimed to examine the association of preoperative intratumoral susceptibility signal (ITSS) grade with hemorrhage after stereotactic biopsy (STB).

METHODS

The authors retrospectively reviewed 66 patients who underwent STB in their institution. Preoperative factors including age, sex, platelet count, prothrombin time-international normalized ratio, activated thromboplastin time, antiplatelet agent use, history of diabetes mellitus and hypertension, target location, anesthesia type, and ITSS data were recorded. ITSS was defined as a dot-like or fine linear low signal within a tumor on susceptibility-weighted imaging (SWI) and was graded using a 3-point scale: grade 1, no ITSS within the lesion; grade 2, 1-10 ITSSs; and grade 3, ≥ 11 ITSSs. Postoperative final tumor pathology was also reviewed. The association between preoperative variables and the size of postoperative hemorrhage was examined.

RESULTS

Thirty-four patients were men and 32 were women. The mean age was 66.6 years. The most common tumor location was the frontal lobe (27.3%, n = 18). The diagnostic yield of STB was 93.9%. The most common pathology was lymphoma (36.4%, n = 24). The ITSS was grade 1 in 37 patients (56.1%), grade 2 in 14 patients (21.2%), and grade 3 in 15 patients (22.7%). Interobserver agreement for ITSS was almost perfect (weighted kappa = 0.87; 95% CI 0.77-0.98). Age was significantly associated with ITSS (p = 0.0075). Postoperative hemorrhage occurred in 17 patients (25.8%). Maximum hemorrhage diameter (mean ± SD) was 1.78 ± 1.35 mm in grade 1 lesions, 2.98 ± 2.2 mm in grade 2 lesions, and 9.51 ± 2.11 mm in grade 3 lesions (p = 0.01). Hemorrhage > 10 mm in diameter occurred in 10 patients (15.2%), being symptomatic in 3 of them. Four of 6 patients with grade 3 ITSS glioblastomas (66.7%) had postoperative hemorrhages > 10 mm in diameter. After adjusting for age, ITSS grade was the only factor significantly associated with hemorrhage > 10 mm (p = 0.029). Compared with patients with grade 1 ITSS, the odds of postoperative hemorrhage > 10 mm in diameter were 2.57 times higher in patients with grade 2 ITSS (95% CI 0.31-21.1) and 9.73 times higher in patients with grade 3 ITSS (95% CI 1.57-60.5).

CONCLUSIONS

ITSS grade on SWI is associated with size of postoperative hemorrhage after STB.

TRPV4 mRNA is elevated in the caudate nucleus with NPH but not in Alzheimer's disease

Symptoms of normal pressure hydrocephalus (NPH) and Alzheimer's disease (AD) are somewhat similar, and it is common to misdiagnose these two conditions. Although there are fluid markers detectable in humans with NPH and AD, determining which biomarker is optimal in representing genetic characteristics consistent throughout species is poorly understood. Here, we hypothesize that NPH can be differentiated from AD with mRNA biomarkers of unvaried proximity to telomeres. We examined human caudate nucleus tissue samples for the expression of transient receptor potential cation channel subfamily V member 4 (TRPV4) and amyloid precursor protein (APP). Using the genome data viewer, we analyzed the mutability of TRPV4 and other genes in mice, rats, and humans through matching nucleotides of six genes of interest and one house keeping gene with two factors associated with high mutation rate: 1) proximity to telomeres or 2) high adenine and thymine (A + T) content. We found that TRPV4 and microtubule associated protein tau (MAPT) mRNA were elevated in NPH. In AD, mRNA expression of TRPV4 was unaltered unlike APP and other genes. In mice, rats, and humans, the nucleotide size of TRPV4 did not vary, while in other genes, the sizes were inconsistent. Proximity to telomeres in TRPV4 was <50 Mb across species. Our analyses reveal that TRPV4 gene size and mutability are conserved across three species, suggesting that TRPV4 can be a potential link in the pathophysiology of chronic hydrocephalus in aged humans (>65 years) and laboratory rodents at comparable ages.

Feasibility of freehand CT and 3-T MR guided brain aspiration biopsies with 18/20-gauge coaxial needles

BACKGROUND AND PURPOSE

An accurate histopathological examination with minimal neuronal damage is essential for optimizing treatment strategies of central nervous system lesions. We investigated the feasibility and safety of CT and 3-tesla (3 T) MR-guided freehand brain aspiration biopsies with 18/20-gauge coaxial needles in performing a single imaging unit.

MATERIALS AND METHODS

We reviewed CT and 3 T-MR guided freehand aspiration biopsies with 18/20-gauge coaxial needles of 33 patients (11-female and 22-male, mean and median ages: 53 years, min-max 21-79 years) in our tertiary hospital within an 8-year-period were included in this retrospective study. Lesion sizes, diagnostic yield, morbidity, and mortality rates of these biopsies without a scalp incision, surgical burr-hole, or stereotactic-instrumentation/neuro-navigation guidance were assessed. All biopsies were performed with local anesthesia and sedation within a single imaging unit of our radiology department. All free-hand biopsies were done as in-patient procedures and the patients were closely observed after the biopsies.

RESULTS

The mean diameter of the lesions was 27 mm (median 25; range 15-46 mm). The diagnostic yield of all free-hand brain biopsies was 88% [one inconclusive result (90%) for 3 T-MR; three inconclusive results (87%) for CT]. There was no major hemorrhage or hematoma, no clinical deterioration, or no infection in our patients on early- and late-phase examinations. Postprocedural minor hemorrhage with a ≤ 2 cm diameter was observed in two patients. The morbidity rate of the study population is 6%. There was no procedure-related infection or mortality in the post-procedural 3 weeks.

CONCLUSIONS

Freehand CT or 3 T-MR guided aspiration biopsy was a safe and feasible method for pathological diagnosis of intracranial lesions. Biopsy workflow was simplified with this technique. It could be considered a valuable alternative for stereotaxic biopsies, especially for centers that do not have stereotaxic equipment or experience.

A comparison of the efficacy, safety, and duration of frame-based and Remebot robot-assisted frameless stereotactic biopsy

OBJECTIVE

The aim of this study was to compare the efficacy, safety, and duration of Remebot robot-assisted frameless brain biopsy with those of standard frame-based stereotactic biopsy.

PATIENTS AND METHODS

A retrospective analysis of 66 patients undergoing stereotactic brain biopsy in our department from January 2015 to January 2019 was performed. We divided the patients into two groups: the frame-based group (n = 35) and the Remebot robot group (n = 31). Data on clinical characteristics, total procedure length, overall discomfort, diagnostic yield, complications, and postoperative length of hospital stay were retrospectively reviewed and compared between these two groups.

RESULTS

No significant difference in diagnostic yield was detected in the two groups, with frame-based biopsy having a diagnostic yield of 91.4% and Remebot robot-assisted frameless brain biopsy having a diagnostic yield of 93.5%. The duration of the total procedure was 116.5 min for the frame-based biopsy and 80.1 min for the Remebot robot-assisted frameless brain biopsy (p < 0.001). There were no statistically significant differences in complication rate or postoperative duration of hospitalization between the two groups. The overall patient discomfort in the frame-based group was significantly greater than that in the Remebot robot group (visual analog scale score 2.7 ± 1.2 versus 1.5 ± 0.7, p = 0.001).

CONCLUSIONS

Remebot robot-assisted frameless brain biopsy was as efficacious and safe as standard stereotactic frame-based biopsy. However, frameless biopsy can alleviate the suffering of the patient and reduce the total duration of the procedure. Remebot robot-assisted frameless brain biopsy is easy to use and better accepted by patients than frame-based biopsy.

Susceptibility-Based Neuroimaging: Standard Methods, Clinical Applications, and Future Directions

The evaluation of neuropathologies using MRI methods that leverage tissue susceptibility have become standard practice, especially to detect blood products or mineralization. Additionally, emerging MRI techniques have the ability to provide new information based on tissue susceptibility properties in a robust and quantitative manner. This paper discusses these advanced susceptibility imaging techniques and their clinical applications.