Improving Stereotaxic Neurosurgery Techniques and Procedures Greatly Reduces the Number of Rats Used per Experimental Group—A Practice Report

Techniques of stereotaxic surgery are commonly used in research laboratories by a range of students, technicians, and researchers. To meet the evolving requirements imposed by international legislation, and to promote the implementation of 3R rules (replacement, reduction, and refinement) by reducing experimental error, animal morbidity, and mortality, it is essential that standard operating procedures and proper conduct following such complex surgeries be precisely described and respected. The present report shows how refinements of our own neurosurgical techniques over decades, have significantly reduced the number of animals (rats) used in experiments and improved the animals’ well-being during the post-surgical recovery period. The current pre-, per-, and post-surgical procedures used in our laboratory are detailed. We describe the practical aspects of stereotaxic neurosurgery that have been refined in our laboratory since 1992 and that cover various areas including appropriate anesthesia and pain management during and after surgery, methods to determine the stereotaxic coordinates, and the best approach to the target brain structure. The application of these optimal surgical methods that combine reliable and reproducible results with an acute awareness of ethics and animal welfare leads to a significant reduction in the number of animals included in experimental research in accordance with ethical and regulatory rules as required by the European Directive on laboratory animal welfare.

EVALUATION OF RADIOLOGICAL FEATURES AND TUMOUR CHARACTERISTICS AND THEIR SIGNIFICANCE IN OUTOME OF INTRACRANIAL MENINGIOMAS

Meningioma is one of the most common intracranial tumours. Several advancements have been made for establishing the etiopathogenesis of meningiomas, including gene mutation and DNA methylation. Many factors have been found to be associated with tumour grade, time to recurrence, overall survival and prognosis. Today, with the availability of detailed radiological assessment and better micro neurosurgical techniques, the outcome has improved signicantly. This study is aimed at evaluating detailed radiological features of meningiomas along with its characteristics like vascularity, adhesiveness and edema and to determine their signicance in outcome. SUMMARY: Meningioma is amongst the most common brain tumours. Several factors have been found to be associated with its origin, growth, grade, time to recurrence, outcome and overall prognosis. This prospective evaluation of 68 consecutive patients of intracranial meningioma was aimed at evaluating their detailed radiological features along with tumour characteristics like vascularity, adhesiveness and edema and to determine their signicance in outcome. Our study showed MRI was most useful tool for preoperative evaluation of tumour characteristics like edema, vascularity and adhesiveness which guide surgical outcome. Less vascular and adhesive tumours had good outcome as compared to highly vascular and strongly adhesive tumours. Size of tumour too was associated with outcome. In our study, all patients (100%) of grade 0 tumour removal had good outcome which was statistically highly signicant (p<0.01). Most common histological variant was transitional type. We advocate aggressive surgical therapy as the primary and main mode of treatment in relation to the preoperative characteristics and features from imaging studies.

Chemogenetics: Beyond Lesions and Electrodes

The field of chemogenetics has rapidly expanded over the last decade, and engineered receptors are currently utilized in the lab to better understand molecular interactions in the nervous system. We propose that chemogenetic receptors can be used for far more than investigational purposes. The potential benefit of adding chemogenetic neuromodulation to the current neurosurgical toolkit is substantial. There are several conditions currently treated surgically, electrically, and pharmacologically in clinic, and this review highlights how chemogenetic neuromodulation could improve patient outcomes over current neurosurgical techniques. We aim to emphasize the need to take these techniques from bench to bedside.

Surgical Resection of a Parietal Osteoma in a Domestic Ferret Using Advanced Neurosurgical Techniques

ABSTRACT A 3.5 yr old male neutered ferret presented with progressive enlargement of a right dorsocaudal skull mass that had occurred over 18 mo. Computed tomography imaging revealed a large (2.4 × 2.7 cm), well-defined, pedunculated osseous mass arising from the right parietal bone. Cytology was inconclusive, and surgical biopsy was consistent with an osteoma. Further enlargement of the mass occurred over the next 3 mo, at which time surgical intervention was pursued. The patient recovered well, despite the persistence of a bony defect at the former mass site, and no mass regrowth occurred in the 14 mo following the surgical resection. This is one of only two reports in the literature to document the surgical removal of an osteoma in a ferret, and this is the sole case in which a custom apparatus was fabricated for head stabilization, a multiaxis adjustable surgical table was used to improve access to the surgical site, and an ultrasonic scalpel was used for the mass resection.

Importance and Evidence of Extent of Resection in Glioblastoma

Maximal safe resection is an essential part of the multidisciplinary care of patients with glioblastoma. A growing body of data shows that gross total resection is an independent prognostic factor associated with improved clinical outcome. The relationship between extent of glioblastoma (GB) resection and clinical benefit depends critically on the balance between cytoreduction and avoiding neurologic morbidity. The definition of the extent of tumor resection, how this is best measured pre- and postoperatively, and its relation to volume of residual tumor is still discussed. We review the literature supporting extent of resection in GB, highlighting the importance of a standardized definition and measurement of extent of resection to allow greater collaboration in research projects and trials. Recent developments in neurosurgical techniques and technologies focused on maximizing extent of resection and safety are discussed.

Functional Neurosurgery in Africa: A Scoping Review

Functional neurosurgery covers a set of neurosurgical techniques that aims at restoring functional neurologic disorders. In Africa, less data is available to map out this activity, though the increased prevalence of diseases such as epilepsy or Parkinson's disease, which results in a high morbidity and mortality rate. However, functional neurosurgery remains very scarce and costly in these countries, hence difficult to implement. A scoping review will be performed to map functional neurosurgery activities in Africa. The Arksey and O’Malley’s scoping review methodology will be used to collect data, and a PRISMA chart used to follow-up data.