Enhancing the Microneurosurgical Training: Development of the Folded Placenta Model for Simulation of the Deep Operative Field Challenges of Cranial Procedures.

BACKGROUND AND OBJECTIVE: Neurosurgery relies heavily on advanced manual skills, necessitating effective training models for skill development. While various models have been utilized, the human placenta has emerged as a promising candidate for microneurosurgical training due to its anatomical similarities with cerebral vasculature. However, existing placenta models have primarily focused on simulating superficial procedures, often neglecting the complexities encountered in deep operative fields during cranial surgeries. METHODS: This study obtained ethical approval and implemented a modified placenta model to address the limitations of existing training models. The key modification involved folding the placenta and placing it within a rigid container, closely mimicking the structural challenges of cranial procedures. The placenta preparation followed a standardized protocol, including the use of specialized equipment for documentation. RESULTS: The primary feature of the modified model is the folded placenta within the rigid container, which replicates cranial anatomy. This innovative approach enables trainees to engage in a comprehensive range of microsurgical exercises, encompassing vessel dissection, aneurysm clipping, tumor resection, and more. The model successfully mirrors the complexities of real cranial procedures, providing a realistic training experience. CONCLUSIONS: The presented modified placenta model serves as an effective tool for simulating the conditions encountered in deep cranial surgeries. By accurately replicating the challenges of deep operative fields, the model significantly enhances the training of neurosurgical residents. It successfully prepares trainees to navigate the intricacies and difficulties inherent in real cranial surgeries, thus contributing to improved surgical skills and readiness for neurosurgical practice.

Case report: Mirror paraclinoid aneurysm associated with mirror clinoidal meningioma.

Introduction: Clinoidal meningiomas and paraclinoid aneurysms are individually uncommon, with the coexistence of mirror paraclinoid aneurysms and clinoidal meningiomas presenting an even rarer scenario. While the association between meningiomas and aneurysms is documented, the simultaneous presence of mirror lesions for both pathologies is not reported in the literature. Clinical presentation: We report a 62-year-old female with a three-month history of moderate bifrontal headaches. Magnetic Resonance Angiography (MRA) revealed mirror paraclinoid aneurysms, prompting surgical intervention. During the procedure, mirror clinoidal meningiomas were incidentally discovered. The left aneurysm was addressed first due to higher rupture risk, followed by the right aneurysm 3 months later. Both meningiomas were confirmed as Transitional Meningiomas (Grade 1; OMS, 2021). The aneurysms were successfully clipped, and the patient had an excellent postoperative outcome. Conclusion: This case represents a unique occurrence of mirror ophthalmic segment internal carotid artery aneurysms associated with mirror clinoidal meningiomas, a combination not previously reported. Despite the limitations of MRA in detecting small meningiomas, it remains a valuable non-invasive screening tool for neurovascular diseases. The case underscores the need for further research to elucidate the association between cerebral aneurysms and meningiomas.

Simplifying the Technique of Awake Brain Surgery in a Condition of Less Equipped Neurosurgical Institution in Uzbekistan.

Currently, awake craniotomy (AC) is one of the most often employed procedures to map and resect tumors in eloquent brain areas, avoiding the use of general anesthesia (GA) and thereby reducing anesthesia-related complications and cost of surgery. Resource limitations are one of the basic reasons for avoiding AC in low- and middle-income countries (LMICs). The aim of this study is to describe the simplified protocol of awake brain surgery that can be implemented in a limited financial setting in LMICs and to share our first experience. Twenty-five patients diagnosed with tumor of the left frontotemporal lobes, all involving Broca's and Wernicke's areas, were operated on using AC. Brain mapping was executed using mono- and bipolar direct electrical stimulation including cortical and subcortical (axonal) mapping profiles, investigating basically cortical language centers. Neither neuronavigation nor intraoperative magnetic resonance imaging (MRI) was utilized due to financial constraints. AC was performed successfully in 23 of 25 patients, achieving a near-total resection in 16 (69.5%) patients, subtotal resection in 4 patients (17.39%) patients, and partial resection in 3 (13.04%) patients. In two patients, due to psychological instability-agitation and fear during the awake phase-speech test was not technically possible, so they were reintubated by giving them GA. There was no mortality in the early or postoperative period. In spite of the absence of advanced pre- and intraoperative technologies such as intraoperative MRI and navigation systems, AC can be safely performed in LMICs. These tools along with intraoperative cortical mapping and language testing can guarantee better surgical outcomes and quality of life. However, our study confirms that omitting these tools does not make a huge difference in getting good results with AC and that AC is not absolutely impossible. AC can be performed successfully, preserving eloquent brain areas, with minimum and basic set of the armamentarium like system for cortical and subcortical intraoperative neurostimulation which provides cortical/subcortical brain mapping.

Orbitozygomatic Transsylvian Resection of a Craniopharyngioma: A Step-by-Step Guide.

Adamantinomatous craniopharyngioma (ACP) is a rare sellar region tumor seen in 0.5-2 cases per million persons each year,1 presenting a bimodal distribution that peaks at 5-15 years in children and 45-60 years in adults.2 Arising from embryonic remnants of the Rathke pouch epithelium, ACPs are associated with calcifications in 90% of cases and grow cranially toward the floor of the diencephalon.1 Craniopharyngiomas are benign but locally aggressive tumors, with microsurgery being the best chance of cure.3 The natural history is to compress the optic apparatus and hypothalamic-pituitary axis as they expand, with a propensity to encase the carotids. Endoscopic transbasal approaches have gained wide acceptance in the management of these tumors.4-6 However, open microsurgical approaches via pterional and orbitozygomatic craniotomies afford wider visualization of different corridors that help mitigate the surgical risks.7-9 The orbitozygomatic craniotomy allows lesions that extend above the optic chiasm to be safely approached from an inferior-to-superior corridor.9 The wide exposure of the basal arachnoid cisterns allows protection of the lenticulostriate perforators during resection.8-11 We demonstrate a step-by-step orbitozygomatic approach with dissection of the sylvian, carotid, carotid-oculomotor, chiasmatic, and lamina terminalis cisterns that allowed safe resection of a third ventricular ACP. The patient was a male in his 70s, who presented with progressive headaches and visual impairment. Magnetic resonance imaging showed a multicystic suprasellar lesion extending through the third ventricle. The surgery was performed with no complication (Video 1). Postoperative vision stabilized, and magnetic resonance imaging showed complete resection.

Cadaveric Sheep Head Model for Anterior Clinoidectomy in Neurosurgical Training.

BACKGROUND: Anterior clinoidectomy is an important procedure used in the treatment of a range of diseases of the frontotemporal region, both vascular and tumoral. Mastering this technique requires a high level of manual skills training. The objective of the study was to describe an easily accessible and economical alternative model of anterior clinoidectomy, with a principal focus on the significance of mastering technical skills and training tactile feedback. METHODS: Five cadaveric sheep heads (10 sides) fixed in formalin and alcohol were injected with silicone and used to simulate extradural (5 sides) and intradural (5 sides) routes and 1 head was used to prepare an anatomic specimen for better demonstration of the anatomy of the paraclinoid region. RESULTS: A comparative anatomic analysis between the ovine and human anterior clinoid process was performed. Using cadaveric sheep models, all principal steps of the procedure for both the extradural and the intradural routes were imitated. CONCLUSIONS: A cadaveric sheep head model serves as a good model of anterior clinoidectomy regarding manual skills training and can serve as a good alternative to human cadaveric training.