Neuroendoscopy has increasingly become a valuable tool for treating several neurosurgical conditions. Ventriculoscopy is now routinely used not only in endoscopic third ventriculostomy but also in procedures such as septostomy, shunt malfunction, ventricular lavage, intraventricular hematoma, multiloculated and complex hydrocephalus, tumor biopsy, cyst fenestration and aqueductoplasty, among others.1, 2, 3, 4, 5, 6, 7 As the range of ventriculoscopic indications expands, the complexity of these procedures naturally rises. To overcome these technical challenges, creative solutions are often required to develop tools that assist us during these demanding surgeries.

Neuronavigation has proved to be a great device for surgical management of several neurosurgical conditions such as tumor resection and biopsy, surgery for epilepsy, spinal procedures, and proximal catheter placement. Combining neuronavigation with anatomic knowledge enables precise intraoperative localization even in cases where the patient's underlying condition has distorted the normal anatomy.8 This integration frequently leads to more precise, efficient, and safe procedures.

Similar to the use of neuronavigation for endonasal skull base surgery or for proximal ventricular catheter placement, neuronavigation has also been described as a tool to assist ventriculoscopic surgeries.9, 10, 11, 12, 13 Most authors advocate for the use of frameless navigation because this option is less time-consuming and avoids the need of bulky stereotaxic frames.14,15 Regarding frameless neuronavigation, some authors use frameless infrared optical-based systems,16, 17, 18 while others prefer frameless, pinless electromagnetic (EM)-based systems.19, 20, 21, 22, 23, 24 Each ventriculoscope and each neuronavigation system has its pros and cons as well as unique features. Although many authors have described the use of neuronavigation during ventriculoscopy, the vast majority do not provide step-by-step details on how the instruments and devices are setup to perform these procedures accurately.

Given that many of these procedures are performed on infants or patients with thin skulls resulting from chronic hydrocephalus, or on patients who may require intraoperative head mobilization, our proposal is centered around the use of frameless, pinless EM-based systems. To simplify and enhance neuronavigation in ventriculoscopy, we present a dynamic workflow proposal for continuous navigation for the LOTTA ventriculoscope (Karl Storz, Tuttlingen, Germany). By using widely available materials, 3-dimensional (3D) printing technology or modifying the original trocar, we describe step-by-step how to navigate the trajectory during the ventriculostomy step and how to navigate the intraventricular work. Our method eliminates the need for rigid head fixation, thus allowing for greater flexibility during the procedure. Additionally, it avoids the use of bulky infrared optical-based attachments on the ventriculoscope, simplifying the setup and enhancing maneuverability.