In cases where autologous bone graft reconstruction is not possible (such as comminuted fractures, bone graft reabsorption, or infection) and the use of synthetic material is required, polymethylmethacrylate (PMMA) use is a safe and efficient solution. Studies comparing the incidence of postoperative complications between autologous and synthetic cranioplasty are heterogeneous, not allowing a conclusion of which is the best material for skull defects reconstruction. Current medical literature lacks prospective well-delineated studies with long-term follow-up that analyze the impact of antibiotic use in PMMA cranial reconstruction of moderate and large defects. A prospective series of patients, who underwent cranioplasty reconstruction with PMMA impregnated with antibiotic, were followed for 2 years. Authors collected data regarding demographic status, clinical conditions, surgical information, and its complications. A total of 58 patients completed full follow-up with a mean group age of 40 years and a male predominance (77%). Major complications that required surgical management were identified in 5 patients, and 10 patients evolved with minor complications. Postoperative surgical site infection incidence was 3.2%. The infection rate in patients submitted to PMMA flap cranioplasty impregnated with antibiotic is significantly inferior comparing to the data described in medical literature. A lower infection incidence impacts secondary endpoints such as minimizing surgical morbidity, mortality, hospitalization period, and, consequently, costs.

INDICATIONS: CORRIDOR AND LIMITS OF EXPOSURE: The endoscopic endonasal transpterygoid approach (EETPA) provides direct access to the petrous apex, lateral clivus, inferior cavernous sinus compartment, jugular foramen, and infratemporal fossa. ^1,2 In the coronal plane, it provides exposure far beyond a traditional sphenoidotomy. ANATOMIC ESSENTIALS: NEED FOR PREOPERATIVE PLANNING AND ASSESSMENT: The pterygoid process of the sphenoid bone forms the junction between the body and greater sphenoid wing before bifurcating because it descends into medial and lateral plates. The key to this exposure lies in the region's bony foramina: the palatovaginal canal, vidian canal, and foramen rotundum. ³ ESSENTIALS STEPS OF THE PROCEDURE: After performing a maxillary antrostomy, stepwise exposure of these foramina leads to the pterygopalatine fossa. The sphenopalatine artery is cauterized as it becomes the posterior septal artery at the sphenopalatine foramen, and the maxillary sinus' posterior wall is opened to expose the pterygopalatine fossa. After mobilizing and retracting the contents of the pterygopalatine fossa, the pterygoid process is removed, improving access in the coronal plane. ⁴ PITFALLS/AVOIDANCE OF COMPLICATIONS: Vidian neurectomy causes decreased or absent lacrimation. Injury to the maxillary nerve or its branches results in facial, palatal, or odontogenic anesthesia or neuralgia. In addition, the EEPTA precludes the ability to raise an ipsilateral nasal septal flap, making it crucial to plan reconstruction preoperatively. ^4,5 VARIANTS AND INDICATIONS FOR THEIR USE: There are 5 variants of the EEPTA: extended pterygopalatine fossa, lateral recess of the sphenoid sinus, petrous apex, infratemporal fossa and petrous carotid artery, and middle and posterior skull base. ⁵ The patient consented to the procedure. Images in the video used with permission as follows: images at 0:33 and 1:15 reused from Bozkurt et al, ³ © Georg Thieme Verlag KG; image at 0:39 from Prosser et al, ⁵ © John Wiley and Sons; images at 0:54, 9:03, and 9:38 from Kasemsiri et al, ¹ © John Wiley and Sons; images at 1:07 and 9:44 from Falcon et al, ² © John Wiley and Sons; image at 1:15 from Sandu et al, ⁴ © Springer Nature.

Introduction: Optimal planning and minimally invasive surgical approach are essential to complete craniopharyngiomas (CP) resection with limited postoperative morbidity. Given the nature of craniopharyngioma recurrence, complete resection of the neoplasm is crucial. Since CP arise from the pituitary stalk and may grow anteriorly or laterally, some cases require an extended endonasal craniotomy. The extension of the craniotomy is crucial to expose the whole tumor and to make its dissection from the surrounding structures feasible. In order to guide the extension of the approach, the intraoperative use of ultrasound is helpful for the surgeons. The objective of this paper is to describe and to demonstrate the applicability of the utilization of intraoperative ultrasound (US) guidance for planning and confirmation of craniopharyngioma resection in EES.Method: The authors selected one operative video of a sellar-suprassellar craniopharyngioma gross-totally resected by EES. The authors demonstrate the extended sellar craniotomy, the anatomic landmarks that guide bone drilling and dural opening, the aspect of the intraoperative real time US, tumor resection and dissection from the surrounding structures.Results: The solid component of the tumor was mostly isoechogenic in texture compared to the anterior pituitary gland, with several wide spread hyperechogenic images corresponding to calcifications and hypoechogenic vesicles corresponding to cysts inside the CF (“salt-and-pepper” pattern).Discussion: The intraoperative endonasal US is a new surgical tool that allows for real-time active imaging for skull base procedures, such as sellar region tumors. Besides tumor evaluation, the intraoperative US helps the neurosurgeon to determine the size of craniotomy, to anticipate the relation between the tumor and vascular structures and to guide the best strategy for gross-total resection of the tumor.Conclusion: The EES allows a straight access to the craniopharyngiomas located in the sellar region or that grow anteriorly or superiorly. This approach allows the surgeon to dissect the tumor with minimal manipulation of the surrounding structures, when compared to craniotomy approaches. In order to accomplish that, the use of intraoperative endonasal ultrasound helps the neurosurgeon to perform the most suitable strategy, optimizing the rate of success.

Among patients with clinical hemifacial spasm (HFS), imaging exams aim to identify the neurovascular conflict (NVC) location. It has been proven that the identification in the preoperative exam increases the rate of surgical success. Despite the description of specific magnetic resonance image (MRI) acquisitions, the site of neurovascular compression is not always visualized. The authors describe a new MRI finding that helps in the diagnosis of HFS, and evaluate the sensitivity, specificity, and interobserver correlation of the described sign. A cross-sectional study including cases of hemifacial spasm treated surgically from 1 August 2011 to 31 July 2021 was performed. The MRIs of the cases were independently evaluated by two experienced neuroradiologists, who were blinded regarding the side of the symptom. The neuroradiologists were assigned to evaluate the MRIs in two separate moments. Primarily, they evaluated whether there was a neurovascular conflict based on the standard technique. Following this initial analysis, the neuroradiologists received a file with the description of the novel sign, named Prevedello Sign (PS). In a second moment, the same neuroradiologists were asked to identify the presence of the PS and, if it was present, to report on which side. A total of 35 patients were included, mostly females (65.7%) with a mean age of 59.02 (+0.48). Since the 35 cases were independently evaluated by two neuroradiologists, a total of 70 reports were included in the analysis. The PS was present in 66 patients (sensitivity of 94.2%, specificity of 91.4% and positive predictive value of 90.9%). When both analyses were performed in parallel (standard plus PS), the sensitivity increased to 99.2%. Based on the findings of this study, the authors conclude that PS is helpful in determining the neurovascular conflict location in patients with HFS. Its presence, combined with the standard evaluation, increases the sensitivity of the MRI to over 99%, without increasing risks of harm to patients or resulting in additional costs.