# Clinical experiences and learning curves from robot-assisted neurosurgical biopsies with Stealth Autoguide™

## TL;DR

This study evaluates robot-assisted brain tumor biopsies using Stealth Autoguide™, finding them safe and effective with a high diagnostic success rate.

## Contribution

The study provides clinical insights and learning curve analysis for a new robotic system in neurosurgical biopsies.

## Key findings

- Robot-assisted biopsies achieved an 87.3% diagnostic yield.
- Surgeons accounted for only 12% of variability in surgery time.
- Complications were comparable to traditional biopsy methods.

## Abstract

Biopsies of intracranial lesions are a cornerstone in the diagnosis of unresectable tumors to guide neurooncological treatment; however, the procedure is also associated with risks. The results from the cranial robot guidance system Stealth Autoguide™ were studied after introduction at a neurosurgical department. Primary aims include the presentation of clinical and radiological data, accuracy of radiological diagnosis, learning curves of the new technology, diagnostic yield, and precision. The secondary aim was to study complications.

Retrospective data inclusion was performed on patients ≥ 18 years undergoing biopsy with Stealth Autoguide™ due to suspected brain tumors in the first 3 years after the introduction of the technique. Data regarding clinical characteristics, intraoperative variables, pathological diagnosis, and complications were recorded. Analyses of learning curves were performed.

A total of 79 procedures were performed on 78 patients with a mean age of 62 years (SD 12.7, range 23–82), 30.8% were female. Tumors were often multifocal (63.3%) and supratentorial (89.9%). The diagnostic yield was 87.3%. The first-hand radiological diagnosis was correct in 62.0%. A slight decrease in operation time was observed, although not significant. The surgeon contributed to 12% of the variability.

Robot-assisted biopsies with Stealth Autoguide™ seem to be comparable, with regards to complications, to frame-based and other frameless neurosurgical biopsies. Learning curves demonstrated no statistical differences in time of surgery and only 12% surgeon-related variation (ie, variation caused by the change of performing surgeon), suggesting a successful implementation of this technical adjunct.

Neurosurgeons will sometimes biopsy a tumor to officially diagnose it if it is too risky to remove with surgery. Biopsies are typically performed by the surgeon without the use of robots. In this study, the authors wanted to describe their experience with robot-assisted brain tumor biopsies. To do this, they reviewed the medical records of patients who had brain tumor biopsies done with a commercial robot. Their results showed that 78 patients had a robot-assisted brain tumor biopsy at their hospital. A diagnosis was achievable for 87% of these patients. The time taken for surgery did not seem to change much over the study period, and the surgeon only accounted for a small portion of the differences in the length of surgery. Although 41% of patients had some bleeding at the site of biopsy, the bleedings were most often small and rarely caused problems for the patient.