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.

Clinical and anatomical analysis of the epileptogenic spread patterns in focal cortical dysplasia patients

Background

Focal cortical dysplasia (FCD) is one of the main causes of intractable epilepsy, which is amendable by surgery. During the surgical management of FCD, the understanding of its epileptogenic foci, interconnections, and spreading pathways is crucial for attaining a good postoperative seizure free outcome.

Methods

We retrospectively evaluated 54 FCD patients operated in Federal Center of Neurosurgery, Tyumen, Russia. The electroencephalogram findings were correlated to the involved brain anatomical areas. Subsequently, we analyzed the main white matter tracts implicated during the epileptogenic spreading in some representative cases. We prepared 10 human hemispheres using Klinger's method and dissected them through the fiber dissection technique.

Results

The clinical results were displayed and the main white matter tracts implicated in the seizure spread were described in 10 patients. Respective FCD foci, interconnections, and ectopic epileptogenic areas in each patient were discussed.

Conclusion

A strong understanding of the main implicated tracts in epileptogenic spread in FCD patient remains cardinal for neurosurgeons dealing with epilepsy. To achieve meaningful seizure freedom, despite the focal lesion resection, the interconnections and tracts should be understood and somehow disconnected to stop the spreading.

Preoperative tractography algorithm for safe resection of tumors located in the descending motor pathways zone

BACKGROUND

Diffusion tensor imaging (DTI) tractography facilitates maximal safe resection and optimizes planning to avoid injury during subcortical dissection along descending motor pathways (DMPs). We provide an affordable, safe, and timely algorithm for preoperative DTI motor reconstruction for gliomas adjacent to DMPs.

METHODS

Preoperative DTI reconstructions were extracted from a prospectively acquired registry of glioma resections adjacent to DMPs. The surgeries were performed over a 7-year period. Demographic, clinical, and radiographic data were extracted from patients' electronic medical records.

RESULTS

Nineteen patients (12 male) underwent preoperative tractography between January 1, 2013, and May 31, 2020. The average age was 44.5 years (range, 19-81 years). A complete radiological resection was achieved in nine patients, a subtotal resection in five, a partial resection in three, and a biopsy in two. Histopathological diagnoses included 10 patients with high-grade glioma and nine with low-grade glioma. A total of 16 perirolandic locations (10 frontal and six frontoparietal) were recorded, as well as two in the insula and one in the basal ganglia. In 9 patients (47.3%), the lesion was in the dominant hemisphere. The median preoperative and postoperative Karnofsky Performance Scores were 78 and 80, respectively. Motor function was unchanged or improved over time in 15 cases (78.9%).

CONCLUSION

This protocol of DTI reconstruction for glioma removal near the DMP shows good results in low-term neurological functional outcomes.

Understanding the molecular profiling of diffuse gliomas classification: A brief overview

Background

Gliomas represent almost 30% of all primary brain tumors and account for 80% of malignant primary ones. In the last two decades, significant progress has been made in understanding gliomas' molecular origin and development. These advancements have demonstrated a remarkable improvement in classification systems based on mutational markers, which contribute paramount information in addition to traditional histology-based classification.

Methods

We performed a narrative review of the literature including each molecular marker described for adult diffuse gliomas used in the World Health Organization (WHO) central nervous system 5.

Results

The 2021 WHO classification of diffuse gliomas encompasses many molecular aspects considered in the latest proposed hallmarks of cancer. The outcome of patients with diffuse gliomas relies on their molecular behavior and consequently, to determine clinical outcomes for these patients, molecular profiling should be mandatory. At least, the following molecular markers are necessary for the current most accurate classification of these tumors: (1) isocitrate dehydrogenase (IDH) IDH-1 mutation, (2) 1p/19q codeletion, (3) cyclin-dependent kinase inhibitor 2A/B deletion, (4) telomerase reverse transcriptase promoter mutation, (5) α-thalassemia/ mental retardation syndrome X-linked loss, (6) epidermal growth factor receptor amplification, and (7) tumor protein P53 mutation. These molecular markers have allowed the differentiation of multiple variations of the same disease, including the differentiation of distinct molecular Grade 4 gliomas. This could imply different clinical outcomes and possibly impact targeted therapies in the years to come.

Conclusion

Physicians face different challenging scenarios according to the clinical features of patients with gliomas. In addition to the current advances in clinical decision-making, including radiological and surgical techniques, understanding the disease's molecular pathogenesis is paramount to improving the benefits of its clinical treatments. This review aims to describe straightforwardly the most remarkable aspects of the molecular pathogenesis of diffuse gliomas.

Photo-Stacking Technique for Neuroanatomical High-Definition Photography and 3D Modeling

BACKGROUND

three-dimensional neuroanatomical knowledge is vital in neurosurgery. Technological advances improved 3D anatomical perception, but they are usually expensive and not widely available. The aim of the present study was to provide a detailed description of the photo-stacking technique for high-resolution neuroanatomical photography and 3D modeling.

METHODS

The photo-stacking technique was described in a step-by-step approach. The time for image acquisition, file conversion, processing, and final production was measured using two processing methods. The toral number and file size of images are presented. Measures of central tendency and dispersion report the measured values.

RESULTS

Ten models were used in both methods achieving 20 models with high-definition images. The mean number of acquired images was 40.6 (14-67), image acquisition time 51.50 ± 18.8s, file conversion time 250 ± 134.6 s, processing time 50.46 ± 21.46 s and 41.97 ± 20.84 s, and 3D reconstruction time was 4.29 ± 0.74 s and 3.89 ± 0.60 s for methods B and C, respectively. The mean file size of RAW files is 1010 ± 452 MB and 101.06 ± 38.09 MB for JPG files after conversion. The mean size of the final image means size is 71.9 ± 0.126 MB, and the mean file size of the 3D model means is 37.4 ± 0.516 MB for both methods. The total equipment used was less expensive than other reported systems.

CONCLUSION

The photo-stacking technique is a simple and inexpensive method to create 3D models and high-definition images that could prove valuable in neuroanatomy training.

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.

Anatomic variations of the floor of the third ventricle: Surgical implications for endoscopic third ventriculostomy

Background:

Endoscopic third ventriculostomy (ETV) is currently used as a treatment for different types of hydrocephalus. However, the anatomical endoscopic variants of the third ventricle floor (3VF), as well as their surgical implications, have been underrated. The anatomic variations of the 3VF can influence the technique and the success rate of the ETV. The purpose of this article is to describe the anatomical variations of 3VF, assess their incidence, and discuss the implications for ETV.

Methods:

Intraoperative videos of 216 patients who underwent ETV between January 2012 and February 2020 at Hospital Infantil Universitario de San José, Bogotá, Colombia were reviewed. One hundred and eighty patients who met the criteria to demonstrate the type of 3VF were selected.

Results:

3VF types were classified as follows: (1) Thinned, (2) thickened, (3) partially erased, (4) globular or herniated, and (5) narrowed.

Conclusion:

Knowledge of anatomical variations of the 3VF is paramount for ETV and it influences the success rate of the procedure.

Microsurgical Anatomy of the Central Retinal Artery

BACKGROUND

The central retinal artery (CRA) has been described as one of the first branches of the ophthalmic artery.It arises medial to the ciliary ganglion and after a sinuous path within the orbital cavity it penetrates the lower surface of the dura mater that covers the optic nerve, approximately 1 cm behind the eyeball. However, the numerous anatomic descriptions that were made of the CRA have been insufficient or unclear in relation to certain characteristics that are analyzed in the present study.

METHODS

An electronic literature search was made in the PubMed database and a cadaver dissection was performed on 11 orbits fixed in formaldehyde.

RESULTS

Results were obtained regarding the source, collateral branches, curves, direction, length of the optic nerve, dural perforation site, distance, path and relations, diameter, and area of the central artery of the retina.

CONCLUSIONS

Our anatomic study innovates in 2 aspects of the CRA: area and curves. Not only was there a simple count of the number of curves, but it also analyzed the angle presented by each of the curves based on photos obtained in high definition, with a digital program to reduce the margin of error. These curvatures of the CRA were classified according to their spatial disposition within the orbital cavity based on a pattern that was easy to understand. Data were obtained from the area of the CRA on the penetration of the CRA into the dural sheath of the optic nerve.