Superior orbital fissure narrowing and tumor-associated pain in spheno-orbital meningiomas.

INTRODUCTION: Spheno-orbital meningiomas (SOMs) represent a distinct subtype of meningioma characterized by their unique multi-compartmental invasion pattern. Previous studies have investigated correlations between SOMs and visual manifestations. However, our comprehension of pain associated with SOMs remains limited. This study aims to provide insight into the pathophysiology underlying SOM-related pain through measurements of tumor volume and superior orbital fissure (SOF) narrowing. METHODS: This retrospective study included patients who underwent surgical resection of a SOM between 2000 and 2022. Preoperative CT and/or MRI scans were analyzed, and the tumor volume of each segment was measured. Bony 3D reconstructions were used to measure the area of the SOF, and SOF narrowing was calculated. RESULTS: The study cohort included 66 patients diagnosed with SOMs, among which 25.8% (n = 17) presented with pain. Postoperatively, 14/17 (82.4%) of patients reported pain improvement. There was no significant correlation between the total volume or the volume of tumor within each compartment and the presence of pain on presentation (p > 0.05). The median SOF narrowing was significantly different between patients presenting with and without tumor-associated pain with median of 11 mm2 (IQR 2.8-22.3) and 2 mm2 (IQR 0-6), respectively (p = 0.005). Using logistic regression, a significant correlation between the degree of SOF narrowing and the presence of SOM-associated pain on presentation was identified, with an aOR of 1.2 (95% CI 1.12-1.3, p = 0.02). CONCLUSION: While the exact cause of tumor-associated pain remains unclear, SOF narrowing seems to play a role in pain among SOM patients. Based on the radiological characteristics, SOF neurovascular decompression is recommended in SOM patients.

The vectorial technique: a novel neuronavigation-based tool to measure angles of exposure during skull base dissections.

The angle of exposure (AnE) represents a metric that is particularly useful for analyzing circular bony structures during skull base dissections. The authors aimed to develop and validate a neuronavigation-based method to measure the AnE. A formula based on vectorial geometry and the coordinates of three points collected with a neuronavigation system was developed to measure the AnE. The method was validated using a plexiglass phantom head. To demonstrate its applicability, the authors measured the AnE in 6 cadaveric specimens after exposure of the hypoglossal canal using a far-medial approach (FMA) and a far-lateral transtubercular approach (FLTA) and in 6 different specimens after exposure of the jugular foramen using an FLTA and a retrosigmoid approach (RSA). The mean angles measured at 45°, 90°, and 180° using a goniometer during the validation test were 44.8° ± 1.1°, 90.8° ± 1.2°, and 179.7° ± 0.8° using the novel formula (p > 0.05). In the first illustrative application, the mean AnEs for the FMA and FLTA were 129° ± 0.9° and 243° ± 1.9°, respectively. In the second scenario, the mean AnEs were 192° ± 1.3° for the FTLA and 143° ± 2.1° for the RSA. The neuronavigation-based technique described is a highly accurate method to measure the AnE.

Oculomotor nerve cavernous malformation: case report and operative video.

BACKGROUND: Cavernous malformations (CMs) are clusters of thin-walled sinusoidal vessels without well-defined walls. Though they can occur anywhere in the neuroaxis, cranial nerve (CN) CMs are rare. METHOD: We report a 47-year-old male with gradual CN III palsy. Initial imaging showed no significant findings, but a follow-up MRI revealed a growing lesion along CN III. Intraoperative findings confirmed a CN III CM. Diagnosing and treating CN III CM are complex. Radiological findings lack specificity, requiring consideration of various diagnoses for patients with isolated CN III palsy and abnormal radiological findings. CONCLUSION: Surgery is the gold standard, aiming for complete lesion removal while minimizing neurological complications.

Exoscope-assisted temporal bone resection: operative videos of the lateral and total techniques.

Skull base malignancies arising from the parotid gland, skin, or external auditory canal (EAC) can potentially involve the temporal bone. Management of these invasive tumors represents a true challenge considering the critical neurovascular relationships. Exoscope-assisted temporal bone resection (TBR) plays a crucial role in addressing such malignancies. The extent of disease is evaluated using the Pittsburgh staging system, which then guides the boundaries of resection. Lateral TBR (LTBR) relies on removal of the EAC and lateral ossicles and is generally appropriate for stage T1 and T2 tumors. Total TBR (TTBR) is reserved for high-grade tumors involving the petrous apex. The video can be found here: https://stream.cadmore.media/r10.3171/2023.10.FOCVID23135.

Volumetric Analysis of Spheno-Orbital Meningiomas: Prognostic Correlation and a Compartmentalized Approach.

BACKGROUND AND OBJECTIVES: Spheno-orbital meningiomas arise from the arachnoid villi cap cells at the sphenoid ridge and have the ability to spread through soft tissue extension and cranial bone invasion. Owing to their orbital hyperostosis and intraorbital soft tissue extension, they commonly present with ophthalmologic manifestations. This study aims to investigate the correlation between tumor volume with the presenting symptoms and postoperative outcomes. METHODS: This retrospective study analyzed patients who underwent surgical resection of spheno-orbital meningiomas. Tumor volumes in different compartments were measured using preoperative and postoperative imaging. Linear and logistic regression analyses were used to identify correlations between tumor volumes and presenting symptoms preoperatively and postoperative outcomes. RESULTS: Sixty-six patients were included in this study, of whom 86.4% had proptosis, 80.3% had decreased visual acuity (VA), 30.3% had visual field defects, and 13.6% had periorbital edema. Preoperatively, proptosis linearly correlated with intraosseous tumor volume (coefficient = 0.6, P < .001), while the decrease in baseline VA correlated with the intraorbital tumor volume (coefficient = 0.3, P = .01). The odds of periorbital edema were found to increase with an increase in intraosseous tumor volume with an adjusted odds ratio of 1.4 (95% CI, 1.1-1.7, P = .003), while the odds of visual field defects were found to increase with an increase in intraorbital tumor volume with an adjusted odds ratio of 2.7 (95% CI, 1.3-5.6, P = .01). Postoperatively, the volume of intraosseous tumor resected linearly correlated with the improvement in proptosis (coefficient = 0.7, P < .001), while the volume of intraorbital tumor resected linearly correlated with improvement in VA (coefficient = 0.5, P < .001) and with a larger effect size in patients presenting with moderate-to-severe decrease in VA preoperatively (coefficient = 0.8). CONCLUSION: Underscoring the importance of each tumor compartment relative to the patient's symptomatology serves as a valuable guide in implementing a compartmentalized resection approach tailored to the surgical objectives.

Therapeutic response to pazopanib: case report and literature review on molecular abnormalities of aggressive prolactinomas.

Introduction: Aggressive prolactinomas (APRLs) pose a significant clinical challenge due to their high rate of regrowth and potentially life-threatening complications. In this study, we present a case of a patient with an APRL who had a trial of multiple therapeutic modalities with the aim to provide a review of molecular abnormalities and management of APRLs by corroborating our experience with previous literature. Methods: A total of 268 articles were reviewed and 46 were included. Case reports and series, and studies that investigated the molecular and/or genetic analysis of APRLs were included. Special care was taken to include studies describing prolactinomas that would fall under the APRL subtype according to the European Society of Endocrinology guidelines; however, the author did not label the tumor as "aggressive" or "atypical". Addiontionally, we present a case report of a 56-year-old man presented with an invasive APRL that was resistant to multiple treatment modalities. Results: Literature review revealed multiple molecular abnormalities of APRLs including mutations in and/or deregulation of ADAMTS6, MMP-9, PITX1, VEGF, POU6F2, CDKN2A, and Rb genes. Mismatch repair genes, downregulation of microRNAs, and hypermethylation of specific genes including RASSF1A, p27, and MGMT were found to be directly associated with the aggressiveness of prolactinomas. APRL receptor analysis showed that low levels of estrogen receptor (ER) and an increase in somatostatin receptors (SSTR5) and epidermal growth factor receptors (EGFR) were associated with increased invasiveness and higher proliferation activity. Our patient had positive immunohistochemistry staining for PD-L1, MSH2, and MSH6, while microarray analysis revealed mutations in the CDKN2A and POU6F2 genes. Despite undergoing two surgical resections, radiotherapy, and taking dopamine agonists, the tumor continued to progress. The patient was administered pazopanib, which resulted in a positive response and the patient remained progression-free for six months. However, subsequent observations revealed tumor progression. The patient was started on PD-L1 inhibitor pembrolizumab, yet the tumor continued to progress. Conclusion: APRLs are complex tumors that require a multidisciplinary management approach. Knowledge of the molecular underpinnings of these tumors is critical for understanding their pathogenesis and identifying potential targets for precision medical therapy.

Thermal Analysis of an Ultrasonic Aspirator Micro Claw Tool Compared With Standard High-Speed Drilling During Internal Auditory Canal Opening in a Cadaveric Model.

BACKGROUND: The ultrasonic aspirator micro claw tool (UAmCT) can be used to remove the bone of the internal auditory canal (IAC) during vestibular schwannoma resection via the retrosigmoid approach (RSA) without the risk of a spinning drill shaft. However, the thermal profile of the UAmCT during IAC removal has not been reported. OBJECTIVE: To compare the thermal profile of the UAmCT during access of the IAC to that of a conventional high-speed drill (HSD) and to present an illustrative case of this application. METHODS: IAC opening via RSA was performed in 5 embalmed cadaveric specimens using the UAmCT with 3, 8, and 15 mL/min irrigation on the left and the HSD at 75 000 revolutions per minute and 0%, 14%, and 22% irrigation on the right. Peak bone surface temperatures were measured 4 times in 20-second intervals, and statistical analyses were performed using SPSS software. An illustrative case of a vestibular schwannoma resected via an RSA using the UAmCT to access the IAC is presented. RESULTS: The IAC was opened in all 5 specimens using both the UAmCT and HSD without complication. The mean peak bone surface temperatures were significantly lower with the UAmCT compared with the HSD ( P < .001). The UAmCT did not meaningfully prolong the operating time in the illustrative case, and the IAC was accessed without complication. CONCLUSION: The UAmCT may be a safe and effective alternative to HSD for IAC opening during vestibular schwannoma resection via the RSA. Larger studies under clinical conditions are required to further validate these findings.

Radial Forearm Free Flap with Parapharyngeal Pedicle Corridor for Reconstruction of Anterior Skull Base Defects.

BACKGROUND: The radial forearm free flap (RFFF) is an indispensable tool for the reconstruction of a range of defects, including those of the skull base. Several options for routing of the RFFF pedicle have been described, and the parapharyngeal corridor (PC) has been proposed as an option and employed for a nasopharyngeal defect. However, there are no reports of its use for the reconstruction of anterior skull base defects. The objective of this study is to describe the technique for free tissue reconstruction of anterior skull base defects using the RFFF and routing of the pedicle via the PC. METHODS: Relevant neurovascular landmarks and critical surgical steps for reconstruction of anterior skull base defects with an RFFF and routing of the pedicle via the PC are reported using an illustrative clinical case and cadaveric dissections. RESULTS: We present a case of a 70-year-old man who underwent endoscopic transcribriform resection of cT4N0 sinonasal squamous cell carcinoma and was left with a large anterior skull base defect that persisted despite several repair attempts. An RFFF was utilized to repair the defect. This report is the first description of the clinical use of the PC for free tissue repair of an anterior skull base defect. CONCLUSIONS: The PC is an option for routing the pedicle during the reconstruction of anterior skull base defects. When the corridor is prepared as described in this case, a direct route exists from the anterior skull base to cervical vessels, simultaneously maximizing the reach of the pedicle and minimizing the risk of kinking.

A Cost-Effective and Reproducible Cadaveric Training Model for Internal Carotid Artery Injury Management During Endoscopic Endonasal Surgery: The Submersible Peristaltic Pump.

BACKGROUND: Internal carotid artery injury (ICAI) represents one of the most challenging complications in endoscopic endonasal neurosurgery and its rarity results in limited opportunities for trainees and surgeons to achieve proficiency in its management. Currently, available models for ICAI have employed costly systems that prevent their widespread use. The objective of this study is to validate an affordable submersible peristaltic pump (SPP)-based model as a reproducible and realistic paradigm for ICAI management training. METHODS: A laceration of the left parasellar internal carotid artery was purposely carried out in 2 human cadaveric heads. A blood substitute was perfused to ensure a perfusion flow of 1 L/min using an affordable SPP. A cohort of 20 neurosurgery and otolaryngology residents, fellows, and attendings were enrolled to evaluate the realism and content validity of the model using a validated 5-grade questionnaire. RESULTS: The model proved to mimic a real intraoperative scenario of ICAI with an expected output flow of 1 L/min. Questionnaire responses reported a realistic experience and the impact of this model on improving trainee surgical coordination and capability to rehearse the most accepted repair technique. The use of a fixed noninjected head allowed the reproducibility of the training session without the additional cost of new fresh-frozen heads. The affordable SPP allowed an impactful reduction of ICAI model training expenses maintaining high realism. CONCLUSIONS: The SPP-based ICAI model with noninjected cadaveric specimens is an affordable and cost-effective system that allows reproducibility and realism. These qualities favor greater adoption in neurosurgery and otolaryngology training curricula.

A rare case of fat embolism syndrome secondary to abdominal liposuction and gluteal fat infiltration.

Fat embolism syndrome (FES) is a rare, life-threatening condition habitually associated with traumatic events such as fractures and, less commonly, burns, liposuction and bone marrow harvesting and transplant [ 1]. The biochemical theory for this condition suggests that fat droplets embolize and convert into fatty acids, eventually leading to toxic injury and inflammation, which results in increased vascular permeability, edema and hemorrhage [ 2]. FES may have an asymptomatic interval lasting 12-72 hours after the insult; however, in some cases, signs have also been seen intraoperatively. Pulmonary signs and symptoms are customarily the earliest and manifest in 75% of patients. Nevertheless, neurologic and dermatologic manifestations are also characteristic, and most severe cases could perhaps present with disseminated intravascular coagulation, right ventricular dysfunction, shock or death. The following case consists of a 37-year-old patient that presented with fat embolism syndrome during liposuction and gluteal fat infiltration.

Ultrashort-segment Hirschsprung disease in a 4-year-old female.

Hirschsprung disease (HSCR) is characterized by the absence of neuronal ganglion cells in a distal portion of the intestinal tract [1]. In 1691, Frederick Ruysch described the disease as congenital megacolon. HSCR-associated congenital anomalies have been reported in 5-32% of affected patients [2]. The clinical symptoms of HSCR are usually evident in the neonatal period. However, in some cases where the extent of the aganglionic segment is short, symptoms may become clinically relevant later in childhood [3]. HSCR is one of the most difficult diseases to identify in pediatric surgery due to its multiple clinical, histological and radiological variations [2, 3]. The goal of surgical management is to remove the aganglionic segment and reconstruct the intestinal tract through techniques such as Swenson, Duhamel and Soave [4]. The following case consists of a 4-year-old patient with a chronic presentation of constipation secondary to ultrashort-segment Hirschsprung disease.

Implementing culturally competent transplant care and implications for reducing health disparities: A prospective qualitative study.

BACKGROUND: Despite available evidence-based interventions that decrease health disparities, these interventions are often not implemented. Northwestern Medicine's® Hispanic Kidney Transplant Program (HKTP) is a culturally and linguistically competent intervention designed to reduce disparities in living donor kidney transplantation (LDKT) among Hispanics/Latinos. The HKTP was introduced in two transplant programs in 2016 to evaluate its effectiveness. OBJECTIVE: This study assessed barriers and facilitators to HKTP implementation preparation. METHODS: Interviews and group discussions were conducted with transplant stakeholders (ie administrators, nurses, physicians) during implementation preparation. The Consolidated Framework for Implementation Research (CFIR) guided interview design and qualitative analysis. RESULTS: Forty-four stakeholders participated in 24 interviews and/or 27 group discussions. New factors, not found in previous implementation preparation research in health-care settings, emerged as facilitators and barriers to the implementation of culturally competent care. Implementation facilitators included: stakeholders' focus on a moral imperative to implement the HKTP, personal motivations related to their Hispanic heritage, and perceptions of Hispanic patients' transplant education needs. Implementation barriers included: stakeholders' perceptions that Hispanics' health insurance payer mix would negatively impact revenue, a lack of knowledge about LDKT disparities and patient data disaggregated by ethnicity/race, and a perception that the family discussion component was immoral because of the possibility of coercion. DISCUSSION AND CONCLUSIONS: Our study identified novel barriers and facilitators to the implementation preparation of a culturally competent care intervention. Healthcare administrators can facilitate organizations' implementation of culturally competent care interventions by understanding factors challenging care delivery processes and raising clinical team awareness of disparities in LDKT.

Nontraumatic chylothorax secondary to lymphoma and filariasis.

Chylothorax is characterized by extravasation of chyle into the pleural space resulting from thoracic duct damage. The effusion is most commonly unilateral, with the right and left side being affected in 50% and 33.3% of the patients, respectively. Only 16.66% of cases present a bilateral effusion. The underlying etiology can be classified as spontaneous or traumatic. The diagnosis is made through pleural fluid analysis and imaging studies. The following article presents two cases of left spontaneous chylothorax: a 26-year-old male presenting with a chylous pleural effusion due to a non-Hodgkin lymphoma and a 47-year-old patient from a tropical area with a chylous pleural effusion attributed to filariasis. Filariasis as a cause of chylothorax is uncommon and there is not much literature on the topic. Alongside the case presentations, information on chylothorax etiology, mechanism, diagnosis and treatment options is provided.