Virtual preoperative planning and 3D tumoral reconstruction with Horos open-source software.

Background: Presurgical three-dimensional (3D) reconstructions allow spatial localization of cerebral lesions and their relationship with adjacent anatomical structures for optimal surgical resolution. The purpose of the present article is to present a method of virtual preoperative planning aiming to enhance 3D comprehension of neurosurgical pathologies using free DICOM image viewers. Case Description: We describe the virtual presurgical planning of a 61-year-old female presenting a cerebral tumor. 3D reconstructions were created with the "Horos®" Digital Imaging and Communications in Medicine viewer, utilizing images obtained from contrast-enhanced brain magnetic resonance imaging and computed tomography. The tumor and adjacent relevant structures were identified and delimited. A sequential virtual simulation of the surgical stages for the approach was performed with the identification of local gyral and vascular patterns of the cerebral surface for posterior intraoperative recognition. Through virtual simulation, an optimal approach was gained. Accurate localization and complete removal of the lesion were achieved during the surgical procedure. Virtual presurgical planning with open-source software can be utilized for supratentorial pathologies in both urgent and elective cases. Virtual recognition of vascular and cerebral gyral patterns is helpful reference points for intraoperative localization of lesions lacking cortical expression, allowing less invasive corticotomies. Conclusion: Digital manipulation of cerebral structures can increase anatomical comprehension of neurosurgical lesions to be treated. 3D interpretation of neurosurgical pathologies and adjacent anatomical structures is essential for developing an effective and safe surgical approach. The described technique is a feasible and accessible option for presurgical planning.

Fresado de hueso temporal: modelo de bajo costo y aplicación sencilla / Temporal bone drilling: low-cost and easy-to-use model

Introducción: Desarrollar y potenciar las habilidades neuroquirúrgicas que se requieren en la disección del hueso temporal aplicado a la realización de abordajes quirúrgicos transtemporales, a través de modelos de bajo costo y aplicación sencilla. Materiales y métodos: Trabajamos sobre huesos temporales secos, con insumos hospitalarios descartables y con materiales básicos obtenidos en ferreterías. Se identificaron con silicona y teflón coloreados con acrílico, estructuras vasculares y nerviosas que forman los principales reparos anatómicos y se utiliza material sintético de látex adherido a la superficie endocraneal para recrear duramadre. Realizamos un estudio exhaustivo del hueso temporal con las diferentes estructuras anatómicas íntimamente relacionadas con él, abordándolo desde diferentes vistas. Una vez familiarizados con la anatomía, se ensayan abordajes neuroquirúrgicos y disecciones anatómicas profundizando el conocimiento sobre las estructuras relevantes no visibles previa a la disección. Discusión: En la formación neuroquirúrgica no solo importa el conocimiento teórico, sino que se requiere praxis eficaz aplicada al mismo y se logra sólo a través de auténticas experiencias, la cual da al practicante, la oportunidad de ensayar aspectos de un abordaje para lograr competencia previa a su aplicación en el paciente. Conclusión: El residente puede utilizar esta técnica de fácil acceso y bajo costo para realzar su experiencia de aprendizaje anatómico y fresado de huesos temporales y así poder discutir aspectos y ensayar un abordaje previo a una cirugía.

Introduction: Develop and enhance the neurosurgical skills required for temporal bone drilling applied to transtemporal surgical approaches through low cost and simple application models. Materials and methods: We worked on dry temporal bones with disposable hospital supplies and basic materials obtained in hardware stores. Vascular and nervous structures that form the main anatomical structures are identified with silicone and Teflon colored with acrylic and synthetic latex material is attached to the endocranial surface to recreate the dura mater. We carried out an exhaustive study of the temporal bone with the different anatomical structures intimately related to it, approaching it from different views. Once familiarized with the anatomy, neurosurgical approaches and anatomical dissections are practiced, increasing the understanding of the relevant structures not visible prior to dissection. Discussion: During neurosurgical training theoretical knowledge is not the only domain that matters, rather effective praxis applied to i t is needed and achieved only through authentic experiences, which gives the practitioner the opportunity to examine aspects of an approach in order to achieve expertise prior to its application to the patient. Conclusion: The resident can use this accessible and low cost technique to enhance their experience in anatomical learning and temporal b ones drilling and therefore, be able to discuss certain aspects and practice an approach prior to surgery.

[Invasive sinonasal papilloma with intracranial invasion: Case report and bibliographic review]. / Papiloma invertido sinunasal con invasión intracraneal: Reporte de caso y revisión bibliográfica.

INTRODUCTION: Inverted papilloma is a locally-aggressive benign neoplasm of the paranasal sinuses with a high potential for recurrence and malignancy. Intracranial extension is infrequent, and dural penetration even more so, typically associated with recurrence of the disease or its degeneration into squamous cell carcinoma. CLINICAL CASE: A 32-year-old female patient consulted us for an exophytic lesion in her right nostril and exophthalmos, associated with headache, anosmia and dysgeusia. Craniofacial and brain CT and brain MRI demonstrated a lesion in the right nostril, extending into the aerial sinuses, orbital lateral wall and anterior fossa, with osteolysis and intracranial invasion towards the right frontal region. A mass effect and brain compression were noted. A histological diagnosis of inverted papilloma was made initially. Upon later resection of the lesion by double access, with reconstruction of the anterior cranial fossa, a definitive diagnosis was made of inverted papilloma of the Schneiderian type, with areas of atypical transformation in situ. Post-operatively, the patient has had a favorable course, with full upper airway patency and neither complications nor signs of recurrence after four years of follow-up. CONCLUSIONS: Intracranial invasion of this pathology is extremely uncommon. When it exists, the tumor has a high potential for local recurrence. Consequently, complete excision of the lesion determines the patient's prognosis.

[Intraventricular schwannoma of the choroid plexus. Case report and review of the literature]. / Schwannoma intraventricular del plexo coroideo. Descripción de un caso y revisión de la bibliografía.

INTRODUCTION: Intraventricular tumors account for approximately 10% of central nervous system tumors. The intraventricular schwannomas are rare because there are only 15 cases reported in the international literature. CASE REPORT: A forty-one years old female, with a history of migraines during 17 years, consulted for headaches and nausea. Brain computed tomography and magnetic resonance imaging evidenced solid nodular lesion at the right occipital horn with homogeneous contrast enhancement. Complete excision was performed through a right parietal craneotomy and a transcortical approach. The postoperative evolution was favorable. The pathology report: schwannoma. The magnetic resonance imaging 18 months after resection showed no recurrence of tumors. CONCLUSION: Intraventricular schwannomas are very rare tumors. Surgery is treatment of choice for total resection. This is a diagnosis to consider in intraventricular tumors.