Successful treatment of medically and surgically refractory lymphocytic hypophysitis with fractionated stereotactic radiotherapy: a single-center experience and systematic literature review.

PURPOSE: To explore the potential role of focused radiotherapy in managing the lymphocytic hypophysitis (LH) refractory to medical therapy and surgery. METHOD: A systematic literature review was conducted following PRISMA guidelines to identify the studies on radiation treatment for hypophysitis, along with the experience in our institution. RESULTS: The study included eight patients, three from our institution and five from existing literature. The age at presentation ranged from 37 to 75 years old, with a median age of 58. The presenting symptoms involved headache in seven patients and diplopia in two patients. Pre-radiation visual field defects were noticed in four patients. All patients exhibited variable degrees of hypopituitarism before radiation, with oral corticosteroids being the initial medical treatment. Immunosuppressive therapy was attempted in two patients prior to radiation. Seven patients had a history of transsphenoidal surgery with a histologically confirmed LH. Three patients underwent stereotactic radiosurgery (SRS), while the remaining received FSRT, with a mean irradiation volume of 2.2 cm3. A single-session total dose of 12 -15 Gy was administered in the SRS group. In the FSRT group, doses ranged from 24 to 30 Gy with a median dose of 25 Gy, delivered in 2 Gy fractions. Four patients achieved a resolution of visual field defects, while another two patients demonstrated improvement in their associated focal neurologic deficits. No change in pre-existing endocrine status was shown after radiation, except in one patient. Clinical response was achieved in seven patients after a single course of radiation, while one patient required the second course. Six patients remained stable on low-dose glucocorticoid during at least a 12-month follow-up period, and one discontinued it entirely without experiencing relapse. Three patients demonstrated a complete radiologic response, while the remaining showed a partial radiologic response. CONCLUSIONS: Focused radiation, including FSRT, can play a role in symptomatic relief, effective mass shrinkage, and minimizing radiation exposure to critical surrounding structures in patients with refractory LH. However, further research efforts are necessary to better clarify its effects and optimal dose planning.

Clinical characteristics and outcomes after trigeminal schwannoma resection: a multi-institutional experience.

Given their rarity, the clinical course of patients undergoing trigeminal schwannoma (TS) resection remains understudied. The objective of this study is to describe clinical characteristics and outcomes in patients undergoing surgical resection for TS in a multi-institutional cohort. This is a retrospective study of patients undergoing TS resection at two institutions between 2004 and 2022. Patient, radiographic, and clinical characteristics were reviewed and analyzed with standard statistical methods. Thirty patients were included. The median patient age was 43 (IQR: 35-52) years, and 14 (47%) patients were female. Median clinical and radiographic follow-ups were 43 (IQR: 20-81) and 47 (IQR: 27-97) months respectively. The most common presenting symptoms were trigeminal hypesthesia (57%) and headaches (30%), diplopia (30%), and ataxia/cerebellar signs (30%). The median maximum tumor diameter was 3.3 (IQR: 2.5-5.4) cm. Most tumors were Samii type C (50%) and mixed cystic-solid (63%). Surgical approaches included endoscopic endonasal (33%), supratentorial (30%), combined/staged (20%), infratentorial (10%), and anterior petrosal (7%) approaches. Gross-total resection was achieved in 16 (53%) patients. Radiographic tumor recurrence was noted in four patients at a median of 79 (range 5-152) months. Twenty-six (87%) patients reported improvements in at least one symptom by last follow-up. The most common perioperative complication was new cranial nerve deficit, with 17% of patients having a transient deficit and 10% having a permanent cranial nerve deficit. Surgical resection of TS showed good progression-free survival and symptom improvement, but was associated with cranial nerve deficits.

Endoscopic endonasal decompression of the optic nerve in the setting of compressive lesions: how I do it.

BACKGROUND: Many lesions in the anterior skull base may compress the optic nerve (ON), leading to vision loss, and even irreversible blindness. Although decompression of the optic nerve has traditionally been achieved transcranially, the endoscopic endonasal approach (EEA) is gaining traction as a minimally invasive approach recently. METHOD: We describe the key steps of an EEA ON decompression. The relevant surgical anatomy with illustration is described. Additionally, a video detailing our technique and instruments on an illustrative case is provided. CONCLUSION: Endoscopic endonasal approach ON decompression with a straight feather blade is a feasible, minimally invasive procedure to decompress the ON in the setting of anterior skull base mass lesions.

Endoscopic endonasal marsupialization of rathke cleft cysts: clinical outcomes and risk factors analysis of visual impairment, pituitary dysfunction, and CSF leak.

OBJECTIVE: This paper assesses the clinical and imaging characteristics, histopathological findings, and treatment outcomes of patients with Rathke's cleft cyst (RCC), as well as identifies potential risk factors for preoperative visual and pituitary dysfunction, intraoperative cerebrospinal fluid (CSF) leak, and recurrence. Through analyzing these factors, the study aims to contribute to the current understanding of the management of RCCs and identify opportunities for improving patient outcomes. METHODS: We performed a retrospective analysis of 45 RCC patients between ages 18-80 treated by Endoscopic Endonasal Approach (EEA) and cyst marsupialization between 2010 and 2022 at a single institution. RESULTS: The median patient age was 34, and 73% were female. The mean follow-up was 70 ± 43 months. Preoperative visual impairment correlated with cyst diameter (OR = 1.41, 95% CI = 1.07 to 1.85, p-value = 0.01) and older age (OR = 1.06, 95% CI = 1.01 to 1.11, p-value = 0.02). Intraoperative CSF leaks were 11 times more likely for cysts ≥ 2 cm (OR = 11.3, 95% CI = 1.25 to 97.37, p-value = 0.03), with the odds of leakage doubling for every 0.1 cm increase in cyst size (OR = 1.41, 95% CI = 1.08 to 1.84, p-value = 0.01). Preoperative RCC appearing hypointense on T1 images demonstrated significantly higher CSF leak rates than hyperintense lesions (OR = 122.88, 95% CI = 1.5 to 10077.54, p-value = 0.03). Preoperative pituitary hypofunction was significantly more likely in patients with the presence of inflammation on histopathology (OR = 20.53, 95% CI = 2.20 to 191.45, p-value = 0.008 ) and T2 hyperintensity on magnetic resonance imaging (MRI) sequences (OR = 23.2, 95% CI = 2.56 to 211.02, p-value = 0.005). Notably, except for the hyperprolactinemia, no postoperative improvement was observed in pituitary function. CONCLUSION: Carefully considering risk factors, surgeons can appropriately counsel patients and deliver expectations for complications and long-term results. In contrast to preoperative visual impairment, preoperative pituitary dysfunction was found to have the least improvement post-surgery. It was the most significant permanent complication, with our data indicating the link to the cyst signal intensity on T2 MR and inflammation on histopathology. Earlier surgical intervention might improve the preservation of pituitary function.

Subfascial dissection and extended temporal muscle detachment for middle fossa approach.

BACKGROUND: The soft tissue dissection for the middle fossa approach requires adequate management of the neuro, vascular, and muscular structures in order to maximize exposure and diminish morbidities. METHODS: An incision anterior to the tragus is performed, extending from the zygomatic process to the superior temporal line. The superior temporal artery is exposed, followed by a subfascial dissection of the frontalis nerve. The temporal muscle is dissected and released from the zygoma. All cranial landmarks are exposed for the 5 × 5 cm temporal fossa craniotomy. CONCLUSION: This novel approach provides a safe and adequate access to perform an extended middle fossa craniotomy.

Effects of Cranioplasty After Decompressive Craniectomy on Neurological Function and Cerebral Hemodynamics in Traumatic Versus Nontraumatic Brain Injury.

After decompressive craniectomy (DC), cranioplasty (CP) can help to normalize vascular and cerebrospinal fluid circulation besides improving the patient's neurological status. The aim of this study was to investigate the effects of CP on cerebral hemodynamics and on cognitive and functional outcomes in patients with and without a traumatic brain injury (TBI). Over a period of 3 years, 51 patients were included in the study: 37 TBI patients and 14 non-TBI patients. The TBI group was younger (28.86 ± 9.71 versus 45.64 ± 9.55 years, P = 0.0001), with a greater proportion of men than the non-TBI group (31 versus 6, P = 0.011). Both groups had improved cognitive outcomes (as assessed by the Mini-Mental State Examination) and functional outcomes (as assessed by the Barthel Index and Modified Rankin Scale) 90 days after CP. In the TBI group, the mean velocity of blood flow in the middle cerebral artery ipsilateral to the cranial defect increased between the time point before CP and 90 days after CP (34.24 ± 11.02 versus 42.14 ± 10.19 cm/s, P = 0.0001). In conclusion, CP improved the neurological status in TBI and non-TBI patients, but an increment in cerebral blood flow velocity after CP occurred only in TBI patients.

A Comparative Study of the Effects of Early Versus Late Cranioplasty on Cognitive Function.

Cranioplasty (CP) after decompressive craniectomy (DC) is associated with neurological improvement. We evaluated neurological recovery in patients who underwent late CP (more than 6 months after DC) in comparison with early CP. This prospective study of 51 patients investigated neurological function using the Addenbrooke's Cognitive Examination Revised (ACE-R), Mini-Mental State Examination (MMSE), Barthel Index (BI), and Modified Rankin Scale (mRS) prior to and after CP. Most patients with traumatic brain injury (74%) were young (mean age 33.4 ± 12.2 years) and male (33/51; 66%). There were general improvements in the patients' cognition and functional status, especially in the late-CP group. The ACE-R score increased from the time point before CP to 3 days after CP (51 ± 28.94 versus 53.1 ± 30.39, P = 0.016) and 90 days after CP (51 ± 28.94 versus 58.10 ± 30.43, P = 0.0001). In the late-CP group, increments also occurred from the time point before CP to 90 days after CP in terms of the MMSE score (18.54 ± 1.51 versus 20.34 ± 1.50, P = 0.003), BI score (79.84 ± 4.66 versus 85.62 ± 4.10, P = 0.028), and mRS score (2.07 ± 0.22 versus 1.74 ± 0.20, P = 0.015). CP is able to improve neurological outcomes even more than 6 months after DC.

Microsurgical Resection of Giant Radio-Induced Cavernous Malformation: 2- Dimensional Video.

Radioinduced cavernous malformations (RICMs) are low-flow, angiographically occult vascular lesions. Giant radioinduced cavernous malformations (GRICMs) are a subtype of RICMs that are characterized by their large size. GRICMs are defined as RICMs that are larger than 3 cm in diameter.1 They are uncommon conditions accounting for 0.1% to 0.5% among patients who have received radiation therapy for head and neck cancer or brain tumors.2,3 The risk of developing GRICMs increases with the dose of radiation received and the length of time since radiation exposure.4 Other factors that may increase the risk of developing GRICMs include age, genetic predisposition, and underlying medical conditions.5 Due to the relatively low incidence of GRICMs and the limited number of studies on this condition, there are limited data about the management of this condition. This case report describes a 12-year-old female who was previously treated for a pilocytic astrocytoma in 2012. After undergoing stereotactic biopsy and whole-brain radiotherapy (50 gray in 28 sections), she was diagnosed with a radioinduced cavernous malformation in 2016 during follow-up imaging. The RICM was managed conservatively with imaging follow-up, which showed no increase in size between 2016 and 2019. However, in 2020, the patient experienced a seizure episode associated with left-sided hemiplegia. Further investigation with cranial magnetic resonance imaging and digital subtraction angiography showed a mixed-intensity image and surrounded by a low signal intensity rim on T2-weighted images, representing hemosiderin in the right central lobe, with intense perilesional edema, with no enhancement. Given the size and location of the mass, the patient underwent microsurgical resection of the RICM (Video 1). The surgery was successful, and the lesion was successfully resected. This case highlights the importance of careful monitoring for RICMs in patients who have received radiation therapy, as well as the potential for these lesions to cause significant symptoms and disability. The case also demonstrates that surgical intervention may be necessary in some cases to manage RICMs and that microsurgical resection can be an effective treatment option. The patient gave informed consent for surgery and video recording.

Management of frontoethmoidal osteoma causing pneumocephalus and cerebrospinal fluid leakage with minimally invasive techniques: illustrative cases.

BACKGROUND: Osteoid osteoma is a common benign bone tumor frequently seen in the frontoethmoid region. However, involvement of the skull base is rare, with few cases previously reported. OBSERVATIONS: The authors report two cases of spontaneous, symptomatic frontoethmoidal osteoma: one presented with neurological deficit secondary to tension pneumocephalus and the other with cerebrospinal fluid leakage. The first case was managed with a transfrontal sinus craniotomy and pneumocephalus decompression with osteoma resection and skull base reconstruction. The second case was managed with a uninaral endoscopic endonasal approach to the anterior skull base with osteoma resection and reconstruction. LESSONS: Given the paucity of cases with associated tension pneumocephalus described in the literature, it was relevant to describe the authors' experience with surgical decision-making and the expected outcomes among patients with this pathology when using minimally invasive techniques.

Outcomes of Extended Middle Fossa Approach for Petroclival Tumors in the Elderly.

Objective The aims of the study are (1) to evaluate the extended middle fossa approach (eMCF) for resection of tumors in the petroclivus and anterior cerebellopontine angle (CPA) and (2) to compare surgical outcomes between elderly (≥65 years) and nonelderly patients. Design Retrospective cohort. Setting Tertiary referral center. Participants Adults with petroclival, anterior CPA, or posterior fossa lesions who underwent an eMCF approach from 2012 to 2021 were included in the study. Main Outcome Measure Demographics, symptoms, cranial nerve (CN) function, and postoperative outcomes. Results Twenty-nine patients (mean age of 55 years, 59% females) were identified. Eleven (38%) were ≥65 years (65-79 years). The most common pathology was meningioma ( n = 13, 45%), followed by vestibular schwannoma ( n = 4, 14%) and squamous cell carcinoma ( n = 3, 10%). Nineteen tumors (65.5%) were located in the petroclivus, 7 (24%) involved the cavernous sinus, and 10 (34%) were located in the posterior fossa. The mean tumor maximal diameter was 3.4 cm (range: 1.3-7.9 cm). Gross total tumor resection was accomplished in 15 (52%) patients. Most patients ( n = 23, 79%) did not develop new CN deficits postoperatively. Of the 13 patients who had complete pre- and postoperative audiometric data, 69% ( n = 9) maintained their hearing. Comparing the elderly versus nonelderly patients, there were no significant differences in the development of new CN palsies ( p = 0.14), length of stay ( p = 0.91), or incidence of postoperative complications ( p = 0.30). Conclusions The eMCF approach provides exposure to the petroclival region, anterior CPA cistern, and posterior fossa for a variety of pathologies. It has a favorable safety profile in the elderly (≥65 years) population with low morbidity.

Endoscopic endonasal approach for resection of sellar leiomyosarcoma metastasis: illustrative case.

BACKGROUND: Leiomyosarcoma (LMS) is a rare neoplasm that arises from tissues of embryonic mesodermal origin. Primary tissues of origin can include smooth muscle cells of the abdominopelvic viscera, blood vessels, or arrector pili muscles. LMS is known to metastasize to the lungs, with few reported cases of spread to the central nervous system. OBSERVATIONS: A 66-year-old male with cutaneous LMS of the left forearm with metastases to the lungs and kidney that had been treated with chemoradiation presented with worsening headaches. Magnetic resonance imaging revealed a sellar lesion. An endocrine workup was unremarkable. Imaging over 6 months revealed rapid interval growth. Positron emission tomography demonstrated moderate uptake. Given the rapid growth, the patient was offered an endoscopic endonasal approach for resection. Pathology confirmed LMS. LESSONS: To the authors' knowledge, this is the first documented case of LMS metastasis to the sella. Pituitary carcinoma or metastases to the sellar region should be in the differential among patients with sellar region tumors with a rapid growth rate, bony erosion, or findings of lesions in the upper cervical lymph nodes or soft tissue. Tumors that show significant interval growth should raise suspicion for nonadenomatous lesions, and surgical intervention should be considered even in the absence of endocrinological dysfunction or cranial neuropathies. https://thejns.org/doi/10.3171/CASE2435.

Management of recurrent giant hemangiopericytoma: illustrative cases.

BACKGROUND: Hemangiopericytoma (HPC) is a rare malignancy accounting for 0.4% of intracranial tumors. HPCs are characterized by local aggressiveness, high rates of recurrence, and a tendency to metastasize to extracranial sites. These features make management of HPCs challenging, often requiring a combination of radical resection and radiation. Given their rarity, optimal treatment algorithms remain undefined. OBSERVATIONS: The authors report a series of four patients who underwent resection of intracranial HPC. Mean age at presentation was 49.3 years. Three patients had reoperation for progression of residual tumor, and one patient was surgically retreated for recurrence. One patient received adjuvant radiotherapy following initial resection, and three patients received adjuvant radiotherapy following resection of recurrent or residual disease. There was one death in the series. Average progression-free survival and overall survival following the index procedure were 32.8 and 82 months, respectively. Progression occurred locally in all patients, with metastatic recurrence in one patient. LESSONS: The current gold-standard treatment for intracranial HPC consists of gross-total resection followed by radiation therapy. This approach allows satisfactory local control; however, given the tendency for these tumors to recur either locally or distally within or outside of the central nervous system, there is a need for salvage therapies to improve long-term outcomes for patients.

The infundibulochiasmatic angle and the favorability of an endoscopic endonasal approach in type IV craniopharyngioma: illustrative case.

BACKGROUND: Lesions located in the floor of the third ventricle are among the most difficult to access in neurosurgery. The neurovascular structures can limit transcranial exposure, whereas tumor extension into the third ventricle can limit visualization and access. The midline transsphenoidal route is an alternative approach to tumor invading the third ventricle if the tumor is localized at its anterior half and a working space between the optic apparatus and the pituitary infundibulum exists. The authors introduce the "infundibulochiasmatic angle," a valuable measurement supporting the feasibility of the translamina terminalis endoscopic endonasal approach (EEA) for resection of type IV craniopharyngiomas. OBSERVATIONS: Due to a favorable infundibulochiasmatic angle measurement on preoperative magnetic resonance imaging (MRI), an endoscopic endonasal transsellar transtubercular approach was performed to resect a type IV craniopharyngioma. At 2-month follow-up, the patient's neurological exam was unremarkable, with improvement in bitemporal hemianopsia. Postoperative MRI confirmed gross-total tumor resection. LESSONS: The infundibulochiasmatic angle is a radiological tool for evaluating the feasibility of EEA when resecting tumors in the anterior half of the third ventricle. Advantages include reduced brain retraction and excellent rates of resection, with minimal postoperative risks of cerebrospinal fluid leakage and permanent pituitary dysfunction.

Ultrasound-guided endoscopic endonasal resection of sellar and suprasellar craniopharyngiomas.

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.

Endoscopic Endonasal Transpterygoid Approach: Technical Lessons.

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. 5The 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.

Endoscopic ultrasound guided resection of a Cushing's adenoma invading the medial cavernous sinus wall using the "interdural peeling" technique.

Cushing's adenoma invading the cavernous sinus requires aggressive resection to be cured. MRI is frequently inconclusive for identifying microadenomas, and visualizing the involvement of the medial cavernous sinus is even more challenging. In this video, the authors present a patient with an adrenocorticotropic hormone (ACTH)-producing microadenoma with doubtful left medial cavernous sinus involvement on MRI. She underwent an endoscopic endonasal exploration of the medial compartment of the cavernous sinus. The abnormally thickened wall, confirmed by intraoperative endoscopic endonasal ultrasound, was safely excised using the "interdural peeling" technique. Complete resection of the tumor resulted in normalization of her postoperative cortisol levels and disease remission with no complications. The video can be found here: https://stream.cadmore.media/r10.3171/2023.4.FOCVID22150.

Real-time ultrasound guidance in the endoscopic endonasal resection of a retro-odontoid pannus: Technical note and case illustration.

Background and Objectives: Odontoidectomy is a surgical procedure indicated in the setting of various pathologies, with the main goal of decompressing the ventral brain stem and spinal cord as a result of irreducible compression at the craniovertebral junction. The endoscopic endonasal approach has been increasingly used as an alternative to the transoral approach as it provides a straightforward, panoramic, and direct approach to the odontoid process. In addition, intraoperative ultrasound (US) guidance is a technique that can optimize safety and surgical outcomes in this context. It is used as an adjunct to neuronavigation and provides intraoperative confirmation of decompression of craniovertebral junction structures in real time. The authors aim to present the use and safe application of real-time intraoperative US guidance during endonasal endoscopic resection of a retro-odontoid pannus. Methods: A retrospective chart review of a single case was performed and presented herein as a case report and narrated operative video. Results: A minimally invasive US transducer was used intraoperatively to guide the resection of a retro-odontoid pannus and confirm spinal cord decompression in real time. Postoperative examination of the patient revealed immediate neurological improvement. Conclusions: Intraoperative ultrasonography is a well described and useful modality in neurosurgery. However, the use of intraoperative US guidance during endonasal endoscopic approaches to the craniovertebral junction has not been previously described. As demonstrated in this technical note, the authors show that this imaging modality can be added to the ever-evolving armamentarium of neurosurgeons to safely guide the decompression of neural structures within the craniocervical junction with good surgical outcomes.

Comparison Between Surgical and Conservative Treatment for AOSpine Type A3 and A4 Thoracolumbar Fractures without Neurological Deficit: Prospective Observational Cohort Study.

Objective To compare the clinical results between conservative (CS) and surgical treatment (CXS) of A3 and A4 fractures without neurological deficit. Methods Prospective observational study of patients with thoracolumbar fractures type A3 and A4. These patients were separated between the surgical and conservative groups, and evaluated sequentially through the numeric rating scale (NRS), Roland-Morris disability questionnaire (RMDQ), EuroQol-5D (EQ-5D) quality of life questionnaire, and Denis work scale (DWS) up to 2.5 years of follow-up. Results Both groups showed significant improvement, with no statistical difference in pain questionnaires (NRS: CXS 2.4 ± 2.6; CS 3.5 ± 2.6; p > 0.05), functionality (RMDQ: CS 7 ± 6.4; CXS 5.5 ± 5.2; p > 0.05), quality of life (EQ-5D), and return to work (DWS). Conclusion Both treatments are viable options with equivalent clinical results. There is a tendency toward better results in the surgical treatment of A4 fractures.

A New Finding on Magnetic Resonance Imaging for Diagnosis of Hemifacial Spasm with High Accuracy and Interobserver Correlation.

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.

A modern approach to olfactory groove meningiomas.

OBJECTIVE: Management of olfactory groove meningiomas (OGMs) has changed significantly with the advances in extended endoscopic endonasal approaches (EEAs), which is an excellent approach for patients with anosmia since it allows early devascularization and minimizes retraction on the frontal lobes. Craniotomy is best suited for preservation of olfaction. However, not infrequently, a tumor presents after extending outside the reach of an EEA and a solely transcranial approach would require manipulation and retraction of the frontal lobes. These OGMs may best be treated by a staged EEA-craniotomy approach. In this study the authors' goal was to present their case series of patients with OGMs treated with their surgical approach algorithm. METHODS: The authors conducted an IRB-approved, nonrandomized historic cohort including all consecutive cases of OGMs treated surgically between 2010 and 2020. Patient demographic information, presenting symptoms, operative details, and complications data were collected. Preoperative and postoperative tumor and T2/FLAIR intensity volumes were calculated using Visage Imaging software. RESULTS: Thirty-one patients with OGMs were treated (14 craniotomy only, 11 EEA only, and 6 staged). There was a significant difference in the distribution of patients presenting with anosmia and visual disturbance by approach. Tumor size was significantly correlated with preoperative vasogenic edema. Gross-total resection was achieved in 90% of cases, with near-total resection occurring twice with EEA and once with a staged approach. T2/FLAIR hyperintensity completely resolved in 90% of cases and rates did not differ by approach. Complication rates were not significantly different by approach and included 4 CSF leaks (p = 0.68). CONCLUSIONS: A staged approach for the management of large OGMs with associated anosmia and significant lateral extension is a safe and effective option for surgical management. Through utilization of the described algorithm, the authors achieved a high rate of GTR, and this strategy may be considered for large OGMs.