Morphometric analysis of the foramen ovale in the Mexican population using computed tomography scan.

Background: The assessment of cranial foramina is an important part of the objective diagnostic and therapeutic study relevant to pathologies involving structures of the skull base. The study of the foramen ovale not only holds significance for anatomical development but also bears profound surgical importance, such as in trigeminal neuralgia, and diagnostic importance in tumors and various types of epilepsy. It becomes relevant in fine-needle aspiration techniques in perineural tumor procedures, for electroencephalographic analysis in seizures, and therapeutic procedures such as percutaneous trigeminal rhizotomy for trigeminal neuralgia. Methods: A cross-sectional study at the Department of Neurosurgery, Specialties Hospital, La Raza National Medical Center, Mexico City, involved 70 patients aged >18 years who underwent a single skull computed tomography scan between July 2023 and March 2024. Patients with sufficient scan quality and optimal visualization of skull base foramina were included in the study. Measurements of tomographic images were taken using Inobitec's DICOM file viewer. Data analysis in Microsoft Excel yielded mean, standard deviation, and 95% confidence interval (CI) for morphometric parameters of the foramen ovale. Results: Analysis of tomographies from 70 patients revealed a total of 140 foramen ovale, evenly split between 25 males (35.7%) and 45 females (64.3%). The measurements for the maximum anteroposterior diameter, transverse diameter, and surface area of all foramina were as follows: 6.61 ± 0.25 mm (95% CI), 3.97 ± 0.21 mm (95% CI), and 20.84 ± 1.58 mm2 (95% CI), respectively. Specific measurements for the right and left sides were obtained: for the right side, 6.59 ± 0.26 mm (95% CI) and 3.89 ± 0.21 mm (95% CI) for the maximum anteroposterior and transverse diameters, respectively, and 20.38 ± 1.62 mm2 (95% CI) for the surface area. For the left side, the measurements were 6.63 ± 0.24 mm (95% CI), 4.05 ± 0.21 mm (95% CI), and 21.31 ± 1.55 mm2 (95% CI) for the maximum anteroposterior diameter, transverse diameter, and surface area, respectively. The maximum and minimum dimensions for anteroposterior and transverse diameters were 10.67 mm, 4.41 mm, 7.09 mm and 2.36 mm, respectively, with a corresponding range for the surface area of 10.16 mm2-44.13 mm2. The average minimum distance between the foramen ovale and the foramen spinosum was 2.32 ± 0.24 mm (95% CI). In males, the average size of the foramen ovale was 23.66 ± 1.61, which was 22% larger than the average size in females (19.28 ± 1.45) (P = 0.0001). Conclusion: The foramen ovale is one of the main anatomical structures of the skull base, and besides that, it is complex and not directly accessible for clinical evaluation, useful information can be obtained through morphometric analysis. The present study provides specific anatomical data with morphological patterns to increase the understanding of the characteristics of the foramen ovale in the Mexican population. These are intended to be helpful in the pursuit of acknowledging the morphometrics and thus being able to plan neurosurgical procedures in the middle cranial fossa.

[Brain aneurysms treatment with pCONus2 device. Initial experience at IMSS]. / Aneurismas cerebrales tratados con dispositivo pCONus2. Experiencia inicial en el IMSS.

Background: pCONus2 device has been used in some countries as coadyuvant in the treatment of wide-neck bifurcation aneurysms with coils. Objective: To present the first series of brain aneurysms treated with pCONus2 in the Mexican Institute for Social Security (IMSS). Material and methods: We retrospectively present the first 13 aneurysms treated from October 2019 to February 2022 with pCONus2 device at a third level hospital. Results: 6 aneurysms located at anterior communicating artery, 3 at middle cerebral artery bifurcation, 2 at internal carotid artery bifurcatión, and 2 at the tip of basilar artery were treated. Device deployment was performed without complications and it was possible to embolize aneurysms with coils in 12 patients (92%), while on an internal carotid bifurcation aneurysm (8%) there was an incident of a pCONus2 petal migration toward vascular lumen caused by coils mesh pressure, situation that was solved by placing an nitinol self-expandable microstent. In 7 cases (54%) we performed coiling technique after microcatheter passage through pCONus2, while in 6 cases (46%) we used the jailing technique without complications. Conclusions: pCONus2 is a useful device for wide-neck bifurcation aneurysms embolization. In Mexico our experience is yet limited; however, the first cases have been successful. Furthermore, we showed the first cases treated using jailing technique. Much more cases are required in order to carry out a statistically conclusive analysis and to establish the effectiveness and safety of the device.

Introducción: el dispositivo pCONus2 ha sido usado en algunos países como coadyuvante en el tratamiento con coils de los aneurismas de cuello ancho localizados en las bifurcaciones. Objetivo: presentar los primeros aneurismas tratados con pCONus2 en el Instituto Mexicano del Seguro Social (IMSS). Material y métodos: se exponen retrospectivamente 13 casos de pacientes tratados con pCONus2 de octubre de 2019 a febrero de 2022 en un hospital de tercer nivel del IMSS. Resultados: se trataron 6 aneurismas de la arteria comunicante anterior, 2 de la bifurcación de la arteria carótida interna, 3 en la bifurcación de la arteria cerebral media y 2 del tope de la arteria basilar. El uso del pCONus2 se hizo sin complicaciones ni incidentes en 12 pacientes (92%), mientras que en un aneurisma de la bifurcación de carótida interna (8%) ocurrió la migración de un pétalo del dispositivo hacia la luz vascular, motivado por la presión de la malla de coils, que se solucionó con un microstent. Siete aneurismas (54%) fueron embolizados con coils después del paso del microcatéter a través del pCONus2, mientras que en 6 (46%) se utilizó la técnica jailing, sin complicaciones ni incidentes. Conclusiones: el pCONus2 es un dispositivo útil en la embolización de aneurismas localizados en bifurcaciones arteriales. En México la experiencia todavía es poca, pero los primeros casos han sido exitosos. Mostramos, además, los primeros casos tratados con la técnica de jailing. Se requieren más casos en nuestro país para hacer un análisis estadísticamente concluyente y determinar la efectividad y seguridad del dispositivo.

Intracranial aneurysms in pediatric population treated with flow diverters: A single-center experience.

Background: Pediatric intracranial aneurysms (PIAs) are uncommon. Flow diverters (FDs) have shown to be effective on treatment of selected aneurysms. Methods: We describe 10 cases of PIAs treated with FDs at one medical center in Mexico, from April 2015 to April 2020. Results: Out of 230 patients treated with FDs, 10 (4.3%) were pediatric. Average age was 9.4 years old (R: 6-15). Two patients (20%) had subarachnoid hemorrhage, 3 had epilepsy (30%), 3 (30%) had clinical signs of cranial nerve compression, and 4 (40%) had only headache. Two patients were in 1a grade of Hunt and Kosnik scale. Out of the nonruptured aneurysms, 7 (70%) were in 15 points of Glasgow Coma Scale and 1 patient (10%) was in 13 points. Treatment was performed without complications; nevertheless, appropriate distal deployment was not achieved in one case. At discharge, nine patients had 5 points of Glasgow Outcome Scale. All patients underwent computed tomography angiography or digital subtraction angiography at 1, 3, 6, and 12 months, 2 patients (20%) had a 2-year follow-up, and 3 patients (30%) had a 3-year follow-up. According to Kamran grading scale, 9 patients (90%) were classified as Grade 4 and 1 patient (10%) as Grade 3. Conclusion: Even though it is a small series, as this is an uncommon disease, we may suggest that FDs are useful to treat properly selected PIAs. Our study has consecutive imaging assessment at least a year of follow-up in which aneurysm stable occlusion was observed in 90% of patients.