Microsurgical and illustrative anatomy of the cavernous sinus, middle fossa, and paraclival triangles: a straightforward, comprehensive review.

The middle fossa, cavernous sinus, and paraclival triangles consist of ten triangles. Their use in a surgical approach is vast; most are used as landmarks to access and identify other structures of surgical interest. Multiple labels, borders, and contents mentioned by different authors make understanding and reproduction challenging and confusing. This study aims to organize and clarify recent or most relevant publications and disclose our portrayal of the ten triangles using cadaveric dissection and simple and practical figures. Four middle fossa triangles, four cavernous sinus triangles, and two paraclival triangles were dissected and delineated in a cadaveric specimen. Drawings were simplified to eliminate confusion and evaluate the triangles effortlessly. Similarities and differences in triangle names, border limits, and contents are described in a precise form. The recognition of triangle landmarks allows for treating pathologies in a frequently distorted anatomy or challenging to access structure. That is why an accurate knowledge of the surgical anatomy should be mastered, and a safe approach should be accomplished.

The sellar barrier on preoperative imaging predicts intraoperative cerebrospinal fluid leak: a prospective multicenter cohort study.

BACKGROUND: The type of sellar barrier observed between a pituitary tumor and cerebrospinal fluid (CSF) on preoperative magnetic resonance imaging (MRI) may predict intraoperative CSF leak during endonasal pituitary surgery. This is the first multicentric prospective cohort trial to study the sellar barrier concept and CSF leak rate during endoscopic pituitary surgery. METHODS: This multi-center, international study enrolled patients operated for pituitary adenomas via fully endoscopic endonasal surgery over a period of 4 months. The independent variable was the subtype of sellar barrier observed on preoperative MRI (strong, mixed or weak); the dependent variable was the presence of an intraoperative CSF leak. The primary goal was to determine the association between a particular type of sellar barrier and the risk of intraoperative CSF leak. Appropriate statistical methods were then applied for data analysis. RESULTS: Over the study period, 310 patients underwent endoscopic endonasal surgery for pituitary tumor. Preoperative imaging revealed a weak sellar barrier in 73 (23.55%), a mixed sellar barrier in 75 (24.19%), and a strong sellar barrier in 162 (52.26%) patients. The overall rate of intraoperative CSF leak among all patients was 69 (22.26%). A strong sellar-type barrier was associated with significantly reduced rate of intraoperative CSF leak (RR = 0.08; 95% CI 0.03-0.19; p < 0.0001), while a weak sellar barrier associated with higher rates of CSF leak (RR = 8.54; 95% CI 5.4-13.5; p < 0.0001). CONCLUSIONS: The preoperative MRI of pituitary patients can suggest intraoperative CSF leak rates, utilizing the concept of the sellar barrier. Patients with a weak sellar barrier carry a higher risk for an intraoperative CSF leak, whereas a strong sellar barrier on MRI seems to mitigate intraoperative CSF leak. We propose that preoperatively assessment of the sellar barrier can prepare surgeons for intraoperative CSF leak repair.

Rating the incidence of iatrogenic vascular injuries in thoracic and lumbar spine surgery as regards the approach: A PRISMA-based literature review.

PURPOSE: To assess the rate, timing of diagnosis, and repairing strategies of vascular injuries in thoracic and lumbar spine surgery as their relationship to the approach. METHODS: PubMed, Medline, and Embase databases were utilized for a comprehensive literature search based on keywords and mesh terms to find articles reporting iatrogenic vascular injury during thoracic and lumbar spine surgery. English articles published in the last ten years were selected. The search was refined based on best match and relevance. RESULTS: Fifty-six articles were eligible, for a cumulative volume of 261 lesions. Vascular injuries occurred in 82% of instrumented procedures and in 59% during anterior approaches. The common iliac vein (CIV) was the most involved vessel, injured in 49% of anterior lumbar approaches. Common iliac artery, CIV, and aorta were affected in 40%, 28%, and 28% of posterior approaches, respectively. Segmental arteries were injured in 68% of lateral approaches. Direct vessel laceration occurred in 81% of cases and recognized intraoperatively in 39% of cases. CONCLUSIONS: Incidence of iatrogenic vascular injuries during thoracic and lumbar spine surgery is low but associated with an overall mortality rate up to 65%, of which less than 1% for anterior approaches and more than 50% for posterior ones. Anterior approaches for instrumented procedures are at risk of direct avulsion of CIV. Posterior instrumented fusions are at risk for injuries of iliac vessels and aorta. Lateral routes are frequently associated with lesions of segmental vessels. Suture repair and endovascular techniques are useful in the management of these severe complications.

Endoscopic anatomy of the sellar barrier: From the anatomical model to the operating room.

BACKGROUND: The sellar barrier concept reflects the association between the components of the roof of the pituitary fossa and the risk of intraoperative cerebrospinal fluid (CSF) leak in the surgery of pituitary adenomas. We based our concept in previous reports on the microsurgical anatomy of the pituitary fossa's superior wall. However, proof of the usefulness of this concept in endoscopic approaches is yet missing. The aim of this study was to describe the endoscopic anatomy of the sellar barrier and its subtypes in a laboratory setting and to provide evidence of its clinical usefulness. METHODS: We provided anatomical models in six fresh-frozen head and neck specimens. We performed an endoscopic endonasal approach and recreated a pathological model of each possible subtype of sellar barrier. To demonstrate the usefulness of this model in clinical practice, we conducted a prospective study including all patients with pituitary adenoma operated by an endoscopic approach between June and July 2019. RESULTS: We successfully recreated the models for each subtype of sellar barrier. When analyzing the clinical cases, we found that intraoperatively, 73.69% (14) had a strong sellar barrier; 21.05% (4) had mixed sellar barrier, and 5.26% (1) had weak sellar barrier. We recorded one case of intraoperative CSF leak in a patient with a weak sellar barrier by magnetic resonance imaging. CONCLUSION: We described the endoscopic anatomy of the sellar barrier and we recreated the three subtypes in anatomical models. We also identified these subtypes in a series of clinical cases, proving its clinical usefulness.

Minimally invasive asterional approach for microvascular decompression in trigeminal neuralgia.

OBJECTIVE: Trigeminal neuralgia (TN) is a neuropathic disorder that can be treated surgically. This study aimed to present the surgical findings and the clinical outcomes of 26 patients with TN treated by minimally invasive asterional surgery. METHODS: Longitudinal descriptive study. Twenty-six patients with TN underwent minimally invasive asterional surgery. The medical history, surgical findings, therapeutic response, and complications were registered. They were followed for 36 months. RESULTS: Nineteen cases were associated with vascular compression; five were associated with arachnoiditis. The two remaining cases were associated with multiple sclerosis and post-herpetic neuralgia. The pain was substantially reduced in all patients in the immediate postoperative period. At 36 months, in 25 patients, total or acceptable pain control was achieved. In the long term, 22 patients evolved with no permanent complications. CONCLUSION: The microvascular decompression surgery by an asterional approach is an alternative with similar results to the classic retrosigmoid approach to treat TN, but that adds the benefits of the principles of minimally invasive surgery. Constant efforts need to be made to optimize minimally invasive surgical techniques for TN.

[Abordaje asterional mínimamente invasivo para descompresión microvascular en neuralgia del trigémino].

OBJECTIVE: Trigeminal neuralgia (TN) is a neuropathic disorder that can be treated surgically. This study aimed to present the surgical findings and the clinical outcomes of 26 patients with TN treated by minimally invasive asterional surgery. METHODS: Longitudinal descriptive study. Twenty-six patients with TN underwent minimally invasive asterional surgery. The medical history, surgical findings, therapeutic response, and complications were registered. They were followed for 36 months. RESULTS: Nineteen cases were associated with vascular compression; five were associated with arachnoiditis. The two remaining cases were associated with multiple sclerosis and post-herpetic neuralgia. The pain was substantially reduced in all patients in the immediate postoperative period. At 36 months, in 25 patients, total or acceptable pain control was achieved. In the long term, 22 patients evolved with no permanent complications. CONCLUSION: The microvascular decompression surgery by an asterional approach is an alternative with similar results to the classic retrosigmoid approach to treat TN, but that adds the benefits of the principles of minimally invasive surgery. Constant efforts need to be made to optimize minimally invasive surgical techniques for TN.

OBJETIVO: La neuralgia del trigémino (NT) es un trastorno neuropático susceptible de tratamiento quirúrgico. El objetivo es presentar los hallazgos quirúrgicos y resultados obtenidos en 26 pacientes con NT, tratados mediante un abordaje asterional mínimamente invasivo para descompresión vascular trigeminal. MÉTODOS: Estudio longitudinal descriptivo. Se intervino mediante abordaje asterional a 26 pacientes. Se registró el historial médico, hallazgos quirúrgicos, respuesta al tratamiento y complicaciones. Se les dio seguimiento durante 36 meses. RESULTADOS: Diecinueve casos se asociaron a compresión vascular, cinco casos a aracnoiditis y los dos restantes se relacionaron con esclerosis múltiple y neuralgia postherpética. El dolor se controló significativamente en todos los pacientes durante el postoperatorio inmediato. A 36 meses de seguimiento, en 25 pacientes se alcanzó un control total o aceptable del dolor. A largo plazo 22 pacientes evolucionaron sin complicaciones permanentes. CONCLUSIONES: La cirugía de descompresión microvascular a través de un abordaje asterional mínimamente invasivo para el tratamiento de la NT es una alternativa con resultados similares al abordaje retrosigmoideo clásico, pero que suma las bondades de una técnica quirúrgica que se rige con los principios de la mínima invasión. Se requieren esfuerzos constantes para optimizar las técnicas quirúrgicas en el tratamiento de la NT.

[Endoscopic treatment of 140 pituitary tumors, results and complications]. / Tratamiento endoscópico de 140 tumores de hipófisis, resultados y complicaciones.

OBJECTIVE: To present the clinical and radiographic outcomes of 140 patients with pituitary adenomas treated by an endoscopic endonasal approach (EEA) over a period of 4 years. MATERIAL AND METHODS: A retrospective analysis was performed between 2011 and 2014. Pre and post operative MRI, ophtalmological assessment, endocrinological laboratory evaluation and surgical morbidity and mortality were assessed. RESULTS: 57,9% of the patients had functional tumors (n=81), acromegaly being the most frequent sub-type (29.3%). 78.6% of the lesions were macroadenomas (n=110) of which 56.4% (n=62) involved the cavernous sinus, 61 patients presented with visual field defects (44%) of which 50.8% of patients showed improvement after surgery. Gross total removal was achieved in 60% of the cases. Hormonal remission was achieved in the 75% of the patients with functional tumors. The morbidity rate was 15% and one patient died after surgery (mortality 0.7%). CONCLUSION: EEA is a safe and effective tool to treat pituitary adenomas. The main limitation for complete surgical resection is the cavernous sinus invasion.

[Facial paralysis surgery. Current concepts]. / Cirugía de la parálisis facial. Conceptos actuales.

Facial palsy is a relatively common condition, from which most cases recover spontaneously. However, each year, there are 127,000 new cases of irreversible facial paralysis. This condition causes aesthetic, functional and psychologically devastating effects in the patients who suffer it. Various reconstructive techniques have been described, but there is no consensus regarding their indication. While these techniques provide results that are not perfect, many of them give a very good aesthetic and functional result, promoting the psychological, social and labour reintegration of these patients. The aim of this article is to describe the indications for which each technique is used, their results and the ideal time when each one should be applied.

Microsurgical Resection of a Medulla Oblongata Cavernoma: 3-Dimensional Operative Video.

Cavernous malformations occur in approximately 0.5% of the population. When it comes to the medulla oblongata, the incidence rate is around 5%.1,2 Patients with these conditions face potential risks such as hemorrhaging, substantial mortality, and morbidity. The symptoms experienced by the patient vary depending on the extent of hemorrhaging and the location of the lesion. Surgery stands as the primary and essential form of treatment in these cases.1-4 The aim of this operative video was to present the removal of a medulla oblongata cavernoma. The patient consented to the procedure and to the publication of her images and surgical video. We describe the case of a 53-year-old woman presenting with headaches and with swallowing difficulties, being tracheostomized on hospital admission. Magnetic resonance imaging showed a lesion located at the medulla oblongata. Owing to the patient's symptoms and cavernoma bleeding, surgical resection was determined. There were no adverse outcomes after surgery, and the patient evolved favorably. Postoperative imaging displayed complete removal of the cavernoma. Microsurgical resection of cavernomas in this location with neurophysiological monitoring and selection of the safe entry zone is an effective option.1-4.

Three-Stage Surgical Resection in Semisitting Position of Sphenocavernopetroclival-Foramen Magnum Meningioma: 3-Dimensional Operative Video.

Large meningiomas extending through the middle cranial fossa, posterior fossa, and foramen magnum (FM) represent a surgical challenge even for experienced skull base surgeons.1 Although decompression may be necessary for offering clinical improvement, surgical risks may involve cranial nerves and vascular injury. We present a case of a sphenocavernopetroclival-FM meningioma, with our surgical plan extending through the sphenoid region, FM, and posterior fossa to the anterior arch of C1. We designed a 2-day, 3-stage surgical strategy to achieve complete surgical resection for offering better long-term prognosis and satisfactory postoperative neurological outcome.2 The surgical plan was completed in 2 days of surgery: the first day the extradural part for achieving optimal tumor exposure and the second day the intradural part to tackle tumor resection in a 3-stage fashion. The first stage consisted in a far lateral approach to access the lower portion of the tumor extending from the FM to the spinal region; the second stage focused on the portion of the tumor extending through the inferior clivus and the petroclival region; and the third stage consisted in resecting the tumor extending from the petroclival region to the sphenoid region.3 A near-total resection was achieved, with a very small tumor remnant observed at the level of the tentorium on postoperative MRI, which was treated with radiosurgery owing to the young age of the patient. This is a 3-dimensional operative video showing the surgical steps of the tumor resection. The patient consented to the procedure and to the publication of her image.

Novel Hybrid Technique for Preservation of Frontal Branch of Facial Nerve: Subgaleal Preinterfascial Dissection.

OBJECTIVE: The pterional approach is the workhorse of skull-base neurosurgery, which allows virtual access to any intracranial lesion around the circle of Willis. Preserving the frontotemporal branch of the facial nerve and conserving the temporal muscle's symmetry are fundamental objectives besides the access that can be obtained through this versatile neurosurgical technique. This manuscript proposes a subgaleal preinterfascial dissection, a novel hybrid technique that provides advantages of previously described temporal muscle dissection techniques while preserving the integrity of facial nerve branches and the unobstructed broad pterional region. We describe the subgaleal preinterfascial dissection as a safe and simple to technique to achieve preservation of the facial nerve frontal branches during anterolateral approaches. METHODS: Two cadaveric heads were skillfully dissected and studied to perform a proper subgaleal preinterfascial dissection on both sides of each cadaver. Afterward, the same technique was employed in 108 patients during a pterional approach for different neurosurgical diseases, with a postoperative follow-up of 6 months. RESULTS: None of the 108 patients presented postoperative frontotemporal branch palsy during postoperative follow-up. Likewise, no complications related to the proposed technique were present. CONCLUSIONS: The subgaleal preinterfascial dissection is a reliable, safe technique that may be employed during a pterional approach with an unobstructed surgical view and excellent cosmetic and functional results, preserving the frontotemporal branch of the facial nerve.

Defining the limits of the anterior wall of the cavernous sinus through an endoscopic view: Cadaveric anatomical study.

Background: The anterior wall of the cavernous sinus (CS) represents an important landmark for endoscopic surgery that although mentioned before, no precise anatomical boundaries have been described. We describe the anatomical landmarks that delimit the anterior wall of the CS, emphasizing its importance as a reference for accessing the CS through endoscopic approaches. Methods: Six adult cadaveric heads fixed with formaldehyde and injected with colored silicone were studied. In all the heads, an endonasal endoscopic approach to the sellar and parasellar regions was performed and the anatomy of the anterior wall of the CS was studied. Results: Four consistent anatomical landmarks that mark the limits of the anterior wall of the CS were found in all the specimens: anterosuperiorly, the lateral opticocarotid recess; posterosuperiorly, the medial opticocarotid recess; anteroinferiorly, the inferior part of the maxillary strut; and posteroinferiorly, the superolateral angle of the clival recess. Conclusion: It is of paramount importance to recognize the anatomical landmarks that define the limits of the anterior wall of the CS to achieve a safe access to this so complex region.

Optic Foraminotomy versus Anterior Clinoidectomy for Small Superior-Projecting Paraclinoid Aneurysms: Visual and Angiographic Outcome Evaluation.

INTRODUCTION: Optic foraminotomy (OF) has been recently proposed as an alternative to anterior clinoidectomy (AC) for selected types of paraclinoid aneurysms. In this study, OF and AC were compared for small superior-projecting paraclinoid aneurysms assuming visual and angiographic results as outcome measures. Indications for OF are also discussed. METHODS: Data of patients who underwent surgery for a paraclinoid aneurysm in the last 10 years were collected across 3 tertiary hospitals. Small to regular-size and superior projecting aneurysms were sorted. Multiple and complex aneurysms were excluded. Records of patients who went through OF were compared with those of patients who underwent AC. Neurologic outcome was reported as a modified Rankin Scale. Aneurysm complete occlusion rate and rate of approach-related worsened vision were selected as outcome measures of efficacy and safety, respectively, of the OF versus AC. Unpaired t test and χ2 test were used for numerical and categorical variables, respectively. A P value less than 0.05 was considered statistically significant. RESULTS: OF and AC groups involved 18 and 25 patients, respectively. Complication rate, overall neurologic outcome, rate of approach-related worsened vision, and complete occlusion rate did not differ between the groups. The average follow-up was 51 ± 34 and 60 ± 41 months in the OF and AC groups, respectively. CONCLUSIONS: Compared to AC, OF did not show either a higher rate of approach-related worsened vision or a lower aneurysm complete occlusion rate. OF can be considered a valid alternative to the AC for small superior-projecting dorsal ICA wall paraclinoid aneurysms.

Comparative Analysis of Surgical Working Corridors for Meckel Cave Trigeminal Schwannomas: A Quantitative Anatomic Study.

BACKGROUND AND OBJECTIVES: Volumetric analysis of the working corridors of the interdural approach to the Meckel cave may lead to a selection of routes which are anatomically more advantageous for trigeminal schwannoma resection. The herein-reported anatomic study quantitively compares the infratrochlear (IT) transcavernous, anteromedial (AM), and anterolateral (AL) corridors, highlighting their feasibility, indications, advantages, and limitations. METHODS: Anatomic boundaries and depth of Meckel cave, porus trigeminus, IT transcavernous, AM, and AL corridors were identified in 20 formalin-fixed latex-injected cadaveric heads and were subsequently measured. The corridor areas and volumes were derived accordingly. Each opening angle was also calculated. Angles and volumes were compared using analysis of variance. Statistical significance was set at a P -value <.05. RESULTS: The IT transcavernous corridor volume was greater than that of the AM and AL. The opening angle of the AM middle fossa triangle was wider than the other 2. CONCLUSION: The IT corridor can be advantageous for Meckel cave schwannomas invading the cavernous sinus and those with a notable extension into the posterior fossa because the transcavernous approach maximizes the working space into the retrosellar area. The AM middle fossa corridor is strategic in schwannomas confined to the Meckel cave with a minor extension into the posterior fossa. It raises the chance of total resection with a single approach involving the porus trigeminus opening.

Guanti bianchi technique for resection of selected pituitary adenomas.

Introduction: Since the introduction of the endoscopic endonasal approach (EEA) to skull base, the nasal phase has been a true challenge as it represents the moment of definition of the corridor, thus defining the instruments maneuverability at tumor removal phase. The longstanding cooperation between ENT and neurosurgeons have provided the possibility of creating adequate corridor with maximal respect toward nasal structures and mucosa. This sparked the idea of entering the sella as thieves, so we named "Guanti Bianchi" technique a lesser invasive variation of the approach for the removal of selected pituitary adenoma. Research Question: The purpose of this study is to present the preliminary results of "Guanti Bianchi" technique. Material and Methods: Data from 17 patients undergoing "Guanti Bianchi" technique (out of 235 standard EEA) at our center, were retrospectively analysed. ASK Nasal-12, a quality-of-life instrument developed specifically to assess patient perception of nasal morbidity, was administered pre- and postoperatively. Results: 10 (59%) patients were men and 7 (41%) women. The mean age was 67.7 (range 35-88). The average duration of the surgical procedure was 71.17 minutes (range 45-100). GTR was achieved in all patients, no postoperative complications were observed. Baseline ASK Nasal-12 was near normal in all patients, 3/17 (17,6%) experienced transitory very mild symptoms without any worsening at 3 and 6 months. Discussion and Conclusions: This minimally invasive technique does not require turbinectomy or carving of the nasoseptal flap, it alters the nasal mucosa as little as necessary, and it is quick and easy to perform.

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.

A simple technique for generating 3D endoscopic images.

Background: Most neurosurgical photographs are limited to two-dimensional (2D), in this sense, most teaching and learning of neuroanatomical structures occur without an appreciation of depth. The objective of this article is to describe a simple technique for obtaining right and left 2D endoscopic images with manual angulation of the optic. Methods: The implementation of a three-dimensional (3D) endoscopic image technique is reported. We first describe the background and core principles related to the methods employed. Photographs are taken demonstrating the principles and also during an endoscopic endonasal approach, illustrating the technique. Later, we divide our process into two sections containing explanations, illustrations, and descriptions. Results: The results of taking a photograph with an endoscope and its assembly to a 3D image has been divided into two parts: Photo acquisition and image processing. Conclusion: We conclude that the proposed method is successful in producing 3D endoscopic images.

Microneurosurgical anatomy of the basal cisterns: A brief review for cisternostomy.

Background: Cisternostomy is a surgical technique thought of and developed as an option for severe brain trauma treatment. It demands a particular knowledge and skill to microsurgically approach basal cisterns and effectively manipulate their contents. To perform this procedure safely, the anatomy and pathophysiology must be clearly understood. Methods: Detailed microscopic dissection and anatomical review were done, after a detailed reading of facts and recent publications about cisternostomy. Cisternal pathways and landmark planning are described and augmented using a new method to show de arachnoid borders. Finally, a brief discussion is written as a synopsis. Results: Cisternostomy requires thorough microscopic knowledge and microsurgical skills. This paper intends to provide information to understand better the anatomy related, thus, easing the learning curve. The technique used to show arachnoid borders, complementing cadaveric and surgical images, was useful for this purpose. Conclusion: To perform this procedure safely, it is mandatory to handle microscopic details of cistern anatomy. Reaching a core cistern is necessary to assure effectiveness. This procedure needs, as well, surgical step-by-step landmark planning and performing. Cisternostomy could be a life-saving procedure and a new powerful tool for severe brain trauma treatment. Evidence is being collected to support its indications.

Surgical corridors to foramen magnum meningiomas: a mini-review.

Gross-total resection of foramen magnum meningiomas remains the gold standard of treatment and should be performed whenever possible. The transcondylar approach (and its variations) represents the most used approach for meningiomas located in the lateral or anterior borders of the foramen magnum. Endoscopic transclivus approaches represent a useful option in selected cases of anterior midline foramen magnum meningiomas, to be performed in centers with advanced experience in endoscopic skull base surgery, with the caveats of increased risk of postoperative cerebrospinal fluid leak. Alternatively, radiosurgery remains an option for well-selected cases, especially for the management of asymptomatic patients with small enlarging tumors. Advances in molecular profiling, as well as genetic analysis, may guide adjuvant treatment.

[Neurovascular decompression in trigeminal neuralgia: Functional outcome]. / Descompresión neurovascular en neuralgia trigeminal: resultado funcional.

INTRODUCTION: The most frequent pathology of the fifth cranial nerve is trigeminal neuralgia (TN), characterized by unilateral orofacial pain, of a paroxysmal nature, with distribution in one or more divisions of the trigeminal nerve. The main objective of this work is to demonstrate the efficacy and safety of neurovascular decompressive surgery (NVD). METHODS: Retrospective analytical study, patients operated on for NVD by TN (n: 155), from January 2006 - 2022, using a retrosigmoid approach and clinicalradiological follow-up, whose intraoperative recording was in 3D system (n: 42). RESULTS: 83.3% (n=35) presented classic NT and 16.7% (n = 7) idiopathic. The right side prevailed with 59.5% (n = 25) and paroxysmal pain with 81% (n=34) of representation in the entire series. Compression of arterial origin represented 76.2% (n: 32) of the cases, the superior cerebellar artery represented the first cause of neurovascular compression (NVC) in 52.4% (n: 22) in the exit zone of the trigeminal nerve. The validity of the magnetic resonance imaging (MRI) protocol selected for this series was analyzed; evidencing a high sensitivity of MRI with 97%, and a specificity of 86%. CONCLUSION: The sensitivity and specificity of highdefinition MRI studies and with special protocols for the evaluation of TN, as gold standard paraclinical, were presented. The DNV offered safe results, a high percentage of the patients were described as successful. The 3D recording allowed retrospective analysis with a vision identical to that of the surgeon during the intraoperative period, the type of NVC.

Introducción: La afección más frecuente del V nervio craneal es la neuralgia del trigémino (NT), se caracteriza por dolor orofacial unilateral, paroxístico, distribuyéndose en una o más divisiones del nervio trigémino. El objetivo de presente trabajo es demostrar la eficacia y seguridad de la cirugía descompresiva neurovascular (DNV). Métodos: Estudio analítico retrospectivo, pacientes intervenidos para DNV por NT (n: 155), desde enero de 2006 - 2022, mediante un abordaje retrosigmoideo y seguimiento clínico-radiológico, cuyo registro intraoperatorio fue en sistema 3D (n: 42). Resultados: 83.3% (n=35) presentó NT clásica y 16.7% (n = 7) idiopática. La mayoría con afectación del lado derecho 59.5% (n = 25) y el dolor paroxístico con 81% (n = 34). La compresión de origen arterial representó 76.2% (n: 32) de los casos, la arteria cerebelosa superior representó la primera causa de compresión neurovascular (CNV) en un 52.4% (n:22) en la zona de salida del nervio trigémino. Se analizó la validez del protocolo de resonancia magnética (RM) seleccionado para esta serie; evidenciando una alta sensibilidad de la RM con 97%, y una especificidad del 86%. Conclusión: Se demostró la sensibilidad y especificidad de los estudios de resonancia magnética (RM) de alta definición y con protocolos especiales para la evaluación de la NT, como paraclínico estándar de oro. La DNV ofreció resultados seguros, un alto porcentaje de los pacientes se calificaron como exitosos. El registro 3D permitió analizar en retrospectiva con una visión idéntica a la del cirujano durante el intraoperatorio, el tipo de CNV.