Endoscopic endonasal pituitary sacrifice for select tumors with retrochiasmatic and/or retrosellar extension: surgical anatomy, operative technique, and case series.

OBJECTIVE: Tumors located in the retrochiasmatic region with extension to the third ventricle might be difficult to access when the pituitary-chiasmatic corridor is narrow. Similarly, tumor extension into the interpeduncular and retrosellar space poses a major surgical challenge. Pituitary transposition techniques have been developed to gain additional access. However, when preoperative pituitary function is already impaired or the risk of postoperative panhypopituitarism (PH) is considered to be particularly high, removal of the pituitary gland (PG) might be the preferred option to increase the working corridor. The aim of this study was to describe the relevant surgical anatomy, operative steps, and clinical experience with the endoscopic endonasal pituitary sacrifice (EEPS) and transsellar approach. METHODS: This study comprised anatomical dissections to highlight the relevant surgical steps and a retrospective case series reporting clinical characteristics, indications, and outcomes of patients who underwent EEPS. The surgical technique is as follows: both lateral opticocarotid recesses are exposed laterally, the limbus sphenoidale superiorly, and the sellar floor inferiorly. After opening the dura, the PG is detached circumferentially and mobilized off the medial walls of the cavernous sinuses. The descending branches of the superior hypophyseal artery are coagulated, and the stalk is transected. After removal of the PG, drilling of the dorsum sellae and bilateral posterior clinoidectomies are performed to gain access to the hypothalamic region, interpeduncular, and prepontine cisterns. RESULTS: From 2018 to 2023, 11 patients underwent EEPS. The cohort comprised mostly tuberoinfundibular craniopharyngiomas (n = 8, 73%). Seven (64%) patients had partial or complete anterior PG dysfunction preoperatively, while 4 (36%) had preoperative diabetes insipidus. Because of the specific tumor configuration, the chance of preserving endocrine function was estimated to be very low in patients with intact function. The main reasons for pituitary sacrifice were impaired visibility and surgical accessibility to the retrochiasmatic and retrosellar spaces. Gross-total tumor resection was achieved in 10 (91%) patients and near-total resection in 1 (9%) patient. Two (18%) patients experienced a postoperative CSF leak, requiring surgical revision. CONCLUSIONS: When preoperative pituitary function is already impaired or the risk for postoperative PH is considered particularly high, the EEPS and transsellar approach appears to be a feasible surgical option to improve visibility and accessibility to the retrochiasmatic hypothalamic and retrosellar spaces, thus increasing tumor resectability.

The "STARS" study: advanced preoperative rehearsal and intraoperative navigation in neurosurgical oncology.

BACKGROUND: Neurosurgical 3D visualizers and simulators are innovative devices capable of defining a surgical strategy in advance and possibly making neurosurgery safer by rehearsing the phases of the operation beforehand. The aim of this study is to evaluate Surgical Theater™ (Surgical Theater LLC, Mayfield, OH, USA), a new 3D neurosurgical planning, simulation, and navigation system, and qualitatively assess its use in the operating room. METHODS: Clinical data were collected from 30 patients harboring various types of brain tumors; Surgical Theater™ was used for the preoperative planning and intraoperative 3D navigation. Preoperative and postoperative questionnaires were completed by first and second operators to get qualitative feedback on the system's functionality. Furthermore, we measured and compared the impact of this technology on surgery duration. RESULTS: Neurosurgeons were overall satisfied when using this rehearsal and navigation tool and found it efficient and easy to use; interestingly, residents considered this device more useful as compared to their more senior colleagues (with significantly higher scores, P<0.05), possibly because of their limited anatomical experience and spatial/surgical rehearsal ability. The length of the surgical procedure was not affected by this technology (P>0.05). CONCLUSIONS: Surgical Theater™ system was found to be clinically useful in improving anatomical understanding, surgical planning, and intraoperative navigation, especially for younger and less experienced neurosurgeons.

The "STARS-CASCADE" Study: Virtual Reality Simulation as a New Training Approach in Vascular Neurosurgery.

OBJECTIVE: Surgical clipping has become a relatively rare procedure in comparison to endovascular exclusion of cerebral aneurysms. Consequently, there is a declining number of cases where young neurosurgeons can practice clipping. For this reason, we investigated the application of a new 3-dimensional (3D) simulation and rehearsal device, Surgical Theater, in vascular neurosurgery. METHODS: We analyzed data of 20 patients who underwent surgical aneurysm clipping. In 10 cases, Surgical Theater was used to perform the preoperative 3D planning (CASCADE group), while traditional imaging was used in the other cases (control group). Preoperative 3D simulation was performed by 4 expert and 3 junior neurosurgeons (1 fellow, 2 residents). During postoperative debriefings, expert surgeons explained the different aspects of the operation to their younger colleagues in an interactive way using the simulator. Questionnaires were given to the surgeons to get qualitative feedback about the simulator, and the junior surgeons' performance at simulator was also analyzed. RESULTS: There were no differences in surgery outcomes, complications, and surgical duration (P > 0.05) between the 2 groups. Senior neurosurgeons performed similarly when operating at the simulator as compared with in the operating room, while junior neurosurgeons improved their performance at the simulator after the debriefing session (P < 0.005). CONCLUSIONS: Surgical Theater proved to be realistic in replicating vascular neurosurgery scenarios for rehearsal and simulation purposes. Moreover, it was shown to be useful for didactic purposes, allowing young neurosurgeons to take full advantage and learn from senior colleagues to become familiar with this demanding neurosurgical subspecialty.

The "STARS-CT-MADE" Study: Advanced Rehearsal and Intraoperative Navigation for Skull Base Tumors.

BACKGROUND: Skull base meningiomas represent a challenge for neurosurgeons, and the procedures are typically performed by experienced neurosurgeons, thus limiting resident training. A new simulation and rehearsal device can be used as an aid for senior surgeons during these operations and serve as a training tool for junior surgeons. METHODS: Forty patients harboring an anterior/middle fossa meningioma were recruited. Surgical Theater, a rehearsal/simulation platform, was used for preoperative planning and intraoperative 3D navigation on 20 patients (CT-MADE group), while the remaining (control group) underwent a traditional navigation. Qualitative comparisons between the 2 groups were made with regard to surgical procedure and patient outcome. Satisfaction questionnaires were completed by expert neurosurgeons and residents to assess the overall usefulness of the platform. Furthermore, the surface of the simulated craniotomy performed during the planning was compared with the one actually performed during surgery in order to evaluate the reliability of the planning. RESULTS: No differences between the 2 groups were found (surgery duration: P = 0.4; visual impairment: P = 0.56). Both residents and senior neurosurgeons enjoyed using the platform for intraoperative navigation and planning; simulated craniotomies were significantly smaller as compared with the real ones (P = 0.009), probably because it was not intuitive to depict the exact margins of the operculum with the platform. CONCLUSION: Surgical Theater helped residents to improve their anatomic and procedural comprehension and was deemed as a useful aid to safely perform some demanding neurosurgical procedures, by both senior and junior surgeons.

Informed consent through 3D virtual reality: a randomized clinical trial.

BACKGROUND: The informed consent is a defining moment that should allow patients to understand their condition, what procedure they are undergoing, and what consequences may follow. This process should foster trust and promote confidence, without increasing patients' anxiety. New immersive 3D imaging technologies may serve as a tool to facilitate this endeavor. METHODS: In a prospective, single-center, randomized controlled clinical trial (SPLICE Study: Surgical Planning and Informed Consent Study; ClinicalTrials.gov NCT03503487), 40 patients undergoing surgery for intracranial tumors were enrolled. After undergoing a traditional surgical informed consent acquisition, 33 patients were randomized 1:1:1 to 3 groups: in 2 experimental groups, patients underwent a 3D, immersive informed consent with two different surgical planners (group 1 and group 2); in the control group, patients underwent an informed consent supported by traditional 2D radiological images. RESULTS: Patients in the experimental groups appreciated this communication experience, while their objective comprehension was higher ((score mean (SD)): group 1 82.65 (6.83); group 2 77.76 (10.19)), as compared with the control group (57.70 (12.49); P < 0.001). Subjective comprehension and anxiety levels did not differ between experimental groups and control group. CONCLUSIONS: 3D virtual reality can help surgeons and patients in building a better relationship before surgery; immersive 3D-supported informed consent improves patients' comprehension of their condition without increasing anxiety. This new paradigm may foster trust between surgeons and patients, possibly restraining medical-legal acts. TRAIL REGISTRATION: ClinicalTrials.gov NCT03503487.

EANS Basic Brain Course (ABC): combining simulation to cadaver lab for a new concept of neurosurgical training.

BACKGROUND: Neurosurgical training has traditionally been based on an apprenticeship model that requires considerable time and exposure to surgeries. Unfortunately, nowadays these requirements are hampered by several limitations (e.g., decreased caseload, worktime restrictions). Furthermore, teaching methods vary among residency programs due to cultural differences, monetary restrictions, and infrastructure conditions, with the possible consequence of jeopardizing residents' training. METHODS: The EANS Basic Brain Course originated from a collaboration between the Besta NeuroSim Center in Milano and the Swiss Foundation for Innovation and Training in Surgery in Geneva. It was held for 5 neurosurgical residents (PGY1-3) who participated to this first pilot experience in January 2019. The main goal was to cover the very basic aspects of cranial surgery, including both technical and non-technical skills. The course was developed in modules, starting from the diagnostic paths and communication with patients (played by professional actors), then moving to practical simulation sessions, rapid theoretical lessons, and discussions based on real cases and critical ethical aspects. At the end, the candidates had cadaver lab sessions in which they practiced basic emergency procedures and craniotomies. The interaction between the participants and the faculties was created and maintained using role plays that smoothly improved the cooperation during debriefs and discussions, thus making the sessions exceedingly involving. RESULTS: At the end of the course, every trainee was able to complete the course curriculum and all the participants expressed their appreciation for this innovative format, with a particular emphasis on the time spent learning non-technical skills, confirming that they feel this to be a fundamental aspect of a comprehensive training in neurosurgery. CONCLUSIONS: It is possible that this combined concept of training on technical and non-technical skills, using emerging technologies along with pedagogic techniques and cadaver dissection, may become the state-of-the-art for European Neurosurgical training programs in the next future.

Filling the gap between the OR and virtual simulation: a European study on a basic neurosurgical procedure.

BACKGROUND: Currently available simulators are supposed to allow young neurosurgeons to hone their technical skills in a safe environment, without causing any unnecessary harm to their patients caused by their inexperience. For this training method to be largely accepted in neurosurgery, it is necessary to prove simulation efficacy by means of large-scale clinical validation studies. METHODS: We correlated and analysed the performance at a simulator and the actual operative skills of different neurosurgeons (construct validity). We conducted a study involving 92 residents and attending neurosurgeons from different European Centres; each participant had to perform a virtual task, namely the placement of an external ventricular drain (EVD) at a neurosurgical simulator (ImmersiveTouch). The number of attempts needed to reach the ventricles and the accuracy in positioning the catheter were assessed. RESULTS: Data suggests a positive correlation between subjects who placed more EVDs in the previous year and those who get better scores at the simulator (p = .008) (fewer attempts and better surgical accuracy). The number of attempts to reach the ventricle was also analysed; senior residents needed fewer attempts (mean = 2.26; SD = 1.11) than junior residents (mean = 3.12; SD = 1.05) (p = .007) and staff neurosurgeons (mean = 2.89, SD = 1.23). Scoring results were compared by using the Fisher's test, for the analysis of the variances, and the Student's T test. Surprisingly, having a wider surgical experience overall does not correlate with the best performance at the simulator. CONCLUSION: The performance of an EVD placement on a simulator correlates with the density of the neurosurgical experience for that specific task performed in the OR, suggesting that simulators are able to differentiate neurosurgeons according to their surgical ability. Namely this suggests that the simulation performance reflects the surgeons' consistency in placing EVDs in the last year.

USim: A New Device and App for Case-Specific, Intraoperative Ultrasound Simulation and Rehearsal in Neurosurgery. A Preliminary Study.

BACKGROUND: Intraoperative ultrasound (iUS) is an excellent aid for neurosurgeons to perform better and safer operations thanks to real time, continuous, and high-quality intraoperative visualization. OBJECTIVE: To develop an innovative training method to teach how to perform iUS in neurosurgery. METHODS: Patients undergoing surgery for different brain or spine lesions were iUS scanned (before opening the dura) in order to arrange a collection of 3-dimensional, US images; this set of data was matched and paired to preoperatively acquired magnetic resonance images in order to create a library of neurosurgical cases to be studied offline for training and rehearsal purposes. This new iUS training approach was preliminarily tested on 14 European neurosurgery residents, who participated at the 2016 European Association of Neurosurgical Societies Training Course (Sofia, Bulgaria). RESULTS: USim was developed by Camelot and the Besta NeuroSim Center as a dedicated app that transforms any smartphone into a "virtual US probe," in order to simulate iUS applied to neurosurgery on a series of anonymized, patient-specific cases of different central nervous system tumors (eg, gliomas, metastases, meningiomas) for education, simulation, and rehearsal purposes. USim proved to be easy to use and allowed residents to quickly learn to handle a US probe and interpret iUS semiotics. CONCLUSION: USim could help neurosurgeons learn neurosurgical iUS safely. Furthermore, neurosurgeons could simulate many cases, of different brain/spinal cord tumors, that resemble the specific cases they have to operate on. Finally, the library of cases would be continuously updated, upgraded, and made available to neurosurgeons.