Response

We thank authors Cardinale et al., directors of the International SEEG course, for their passionate feedback on our article, and we are humbled that some of our standard work tools were of interest. As modern medicine trends toward the standardization of care, efforts to document and apply standardized workflows to surgical procedures facilitates operative efficiency while balancing competing interests, including surgical training.^1–4 Process improvement that targets surgery should involve surgeons as key stakeholders. As Cardinale and colleagues highlight, the creation of standard work tools for stereo-electroencephalography (sEEG) is innovative, and our article delineates how these tools were used: first, to streamline an existing process, and second, to duplicate that process at another institution. We are grateful for the opportunity to clarify the intent of our report, which was to identify the impact of standardization of neurosurgical procedures performed by neurosurgeons as it relates to sEEG.

Merriam-Webster’s dictionary defines “dynamic” as an adjective meaning “marked by usually continuous and productive activity or change.”⁵ Our selection of this word was meant to convey the spirit of continuous work that marks the quality and process improvements that were our goals in this endeavor.

As the use of sEEG with epilepsy surgery increases throughout the world, there are increasing numbers of neurologist-epileptologists, radiologists, neurosurgeons, neurophysiologists, and EEG technicians involved in care teams and research. At many institutions, there are also students on these teams. In order to facilitate and standardize communication in increasingly complex healthcare teams, tools for improving quality and streamlining processes are important. While issues that motivate quality improvement are often local, there are themes involved in this endeavor that are echoed through multiple clinical teams regardless of institutions and borders.

In their letter the authors correctly point out that our manuscript is not a historical review, and we are grateful for their addition of important perspectives and highlights. There is no questioning the magnitude of the contributions made by the French and Italian pioneers in the surgical implantation of depth electrodes (DEs). On the basis of their findings, DE trajectories have always been highly considered in diagnosing epileptogenesis and identifying the epileptogenic zone (EZ). Regardless of surgical technique, the placement of DEs is a surgically nuanced procedure that is based on synthesis of multimodal information in the epilepsy workup. The current techniques now incorporate technologies that were previously not available. These technologies include robotic assistance and computer guidance, with continual advances in structural and functional imaging. Surgical plans may be modified based on the suspected morphology of the EZ or local thermodynamics to take advantage of technological advancements in therapy such as laser interstitial thermal therapy (LITT). We specify that this philosophy of ongoing care improvement aided by new technology includes DEs in our definition of the term “dynamic sEEG” as a vital tool in the “quest for localization of the SOZ … placed in a trajectory that would optimize the subsequent laser ablation of that SOZ.” This defines a diagnostic targeting process which is optimized for passage of a laser along the same trajectory and through the same bolt—a clear evolution in incorporating technologies, which is built on the framework of previous descriptions of sEEG.

Cardinale and colleagues further suggest, “The resulting names seem to us too complicated, but only the acceptance rate from the pertinent community will provide an assessment of the effective usability of the proposed system.” We respect this viewpoint. The Letter to the Editor forum is a welcome avenue for thoughtful discussion. Current naming conventions are alphanumeric, yet unformatted; although this simplicity has advantages, the current system misses an opportunity to encode the extensive data underlying the anatamo-electro-clinical hypothesis which led to the creation of the system. In addition, the terms used are usually designed to name and plan open surgical resections, and thus they identify whole structures, the dimensions of which are beyond the maximum ablation volume of a single laser. Our presented naming convention has limitations, such as the coding of ictal and interictal EEG data. This limitation and others will be further addressed with more use and collective experience.

As multicenter and global research collaboration becomes the norm, the ability to archive and communicate the complex information from each surgical epilepsy case will be increasingly relevant. While the method we present is in its early stages, we ask the field to join us in the design thinking, uptake, evaluation, adjustment, and refinement that will enable the bringing together of the power of multiple centers to continue to push the field of epilepsy surgery to deliver better outcomes for patients and their families.

Since the first implementation of sEEG by the French and Italian cognoscenti, there have passed decades of technological advancement during which the management of epilepsy patients has improved. Surgical process improvement is inexorably linked with the education of neurosurgeons and multidisciplinary teams. We all agree that standard work tools are not “simple stuff,” they are the basis upon which thoughtful innovation emerges, and higher-order thinking evolves.⁶