Postoperative Third Nerve Palsy after Endoscopic Endonasal Transsphenoidal Surgery for Pituitary Adenoma: Elucidating its Mechanism.

Third nerve palsy is a rare complication of transsphenoidal surgery and has been merely mentioned in different studies, but there is not any rigorous analysis focusing on this particular complication. The purpose of this study is to analyze this complication after transsphenoidal surgery for a pituitary adenoma to better understand its pathophysiology and outcome. The authors retrospectively analyzed 3 cases of third nerve palsy selected from the 377 patients operated via a transsphenoidal route between 2012 and 2021 at FLENI, a private tertiary neurology and neurosurgical medical center located in Buenos Aires, Argentina. The three patients who presented this complication were operated on via an endoscopic approach. It was observed that an extension into the cavernous sinus (Knosp grade 4) and to the oculomotor cistern was present in the three patients. The deficit was apparent immediately after surgery in two patients. For these two patients, the supposed mechanism of ophthalmoplegia was an intraoperative nerve lesion. The other patient became symptomatic in the 48 h following the surgery. The mechanism implied in this case was intracavernous hemorrhagic suffusion. The latter patient completely recovered the third nerve deficit in the 3 months that followed, while the other two recovered after 6 months postoperative. Oculomotor nerve palsy after transsphenoidal surgery is a very rare complication and appears to be transient in most cases. The invasion of both the cavernous sinus and the oculomotor cistern seems to be a major factor in its physiopathology and should be preoperatively analyzed on magnetic resonance imaging (MRI); recognizing such extension should play an important role in the surgeon's operative considerations.

Cerebellar pilocytic astrocytoma. Retrospective cohort study assessing postoperative functional outcome, cerebellar mutism and hydrocephalus.

Objective: Analyze a series of pediatric patients with cPAs evaluating factors that may modify or determine the final outcome in terms of neurological status, CMS and hydrocephalus. Materials and methods: Single Center, retrospective cohort study of surgical patients with cPA and at least 12 months of follow-up. Clinical, imaging and surgical features, histopathology and adjuvancy were assessed. Clinical outcome was categorized using the FSS and modified Bloom-Scale in the short and long term. Recurrency, PFS and mortality were also analyzed. Results: A total of 100 patients with a mean follow-up of 53.9 months, with no gender predilection, and a mean age of 7.6 years were included. The most frequent location was central and 24% of the tumors presented brainstem invasion. 79 patients had hydrocephalus at diagnosis and 48% required preoperative treatment. RT was achieved in 67% of cases. CMS was observed in 15 patients, statistically associated with location, pontine invasion, preoperative Bloom-score, and postoperative meningitis/ventriculitis. The functional "outcome" was correlated with complications such as meningitis/ventriculitis and cerebellar hematoma, mutism and recurrence. Recurrence was observed in 26% of cases and surgical reintervention was the chosen therapy. Conclusion: The treatment of cPAs in pediatric patients is associated with relatively favorable results. Recurrence, CMS and surgical complications play a prognostic value in the outcome and therefore must be managed appropriately. Early treatment with the intention of GTR should be considered, opting, if this is not possible, to leave a tumor residue over neurological damage. The treatment of hydrocephalus in the preoperative instance requires individualized management.

Risk Factors Related to Transient Diabetes Insipidus Development Following Transsphenoidal Pituitary Adenoma Resection: A Multicentric Study.

OBJECTIVE: To analyze and find risk factors associated with developing transient diabetes insipidus (DI) using a multicenter case series after trans-sphenoidal surgery. METHODS: Medical records of patients who underwent trans-sphenoidal surgery for pituitary adenoma resection between 2010 and 2021 at 3 different neurosurgical centers by 4 experienced neurosurgeons were retrospectively analyzed. The patients were divided into 2 groups (DI group or control group). Logistic regression analysis was conducted to identify risk factors associated with postoperative DI. Univariate logistic regression was performed to identify variables of interest. Covariates with a P value <0.05 were incorporated into multivariate logistic regression models to identify independently associated risk factors for DI. All statistical tests were conducted using RStudio. RESULTS: A total of 344 patients were included; 68% were women, the mean age was 46.5 years, and nonfunctioning adenomas were the most frequent (171, 49.7%). The mean tumor size was 20.3 mm. Covariates associated with postoperative DI were age, female gender, and gross total resection. The multivariable model showed that age (odds ratio [OR] 0.97, CI 0.95-0.99, P = 0.017) and female gender (OR 2.92, CI 1.50-6.03, P = 0.002) remained significant predictors of DI development. Gross total resection was no longer a significant predictor of DI in the multivariable model (OR 1.86, CI 0.99-3.71, P = 0.063), suggesting that this variable may be confounded by other factors. CONCLUSIONS: The independent risk factors for the development of transient DI were female and young patients.

Which biological pathways are responsible for the late appearance of brain metastases in renal cell carcinoma? Analysis of eight cases.

Background: Renal cell carcinoma (RCC) represents 1% of all cancers and its brain metastases amount to 8.1% of all metastatic tumors. Late brain metastases are defined as tumors that appear 10 years after diagnosis of the primary lesion. The objective of this work is to discuss which biological pathways are responsible for the late appearance of these metastases analyzing eight cases. Case Description: We report here eight cases of late brain metastases of RCC treated between 2018 and 2021. Patients consulted for different clinical complaints. Brain magnetic resonance imaging and computed tomography scan were performed on all patients. They were treated by complete surgical resection plus radiosurgery or by radiosurgery alone. The histology of most metastases showed clear cell RCC. Conclusion: In the presence of a patient with an intracranial tumor and a history of RCC with more than 10 years of evolution, the presence of late metastasis should always be considered. There are many theories described in the literature that try to explain the late appearance of brain metastases from RCC (low mitotic index, impaired immune system, cross talk, self-seeding, and among others).

Surgical Treatment of IV Ventricle Calcifying Pseudoneoplasm of the Neuraxis (CAPNON) Operative Nuances.

Calcifying pseudoneoplasm of the neuroaxis (CAPNON) is a rare, slow growing, and generally benign fibro osseous mass that can emerge throughout the entire central nervous system (CNS). When diagnosed, prompt surgical treatment can determine a good neurological outcome and possibly curative resolution. The objective of the present work is to present a step by step technical report with its video. We present a 37 year old female presented with occipital headache and cervical pain associated with dysphagia, nausea, and gait disturbances. Computed tomography (CT) scan showed a focal calcified lesion on the floor of the IV ventricle projecting toward the vermis with associated supratentorial hydrocephalus and transependymal edema. The telovelar approach was chosen for the procedure. The outcome was favorable, with no complications. Postoperative CT was performed, which revealed no residual lesion. A step by step report of a IV ventricle CAPNON that manifested with hydrocephalus is described.

Scalpel Sign in Spine Pathology: Presentation in 3 Different Rare Diagnoses.

BACKGROUND: The scalpel sign is a radiological finding observed on sagittal magnetic resonance imaging and computed tomography myelography corresponding to an indentation in the dorsal aspect of the spinal cord resembling a surgical scalpel blade. It is said to be a pathognomonic imaging discovery linked to dorsal arachnoid webs. However, other spine-related conditions may mimic dorsal arachnoid webs on magnetic resonance imaging, such as spinal arachnoid cysts or ventral spinal cord herniation, leading to misdiagnosis. METHODS: A retrospective review was performed of cases involving 3 different diagnoses at our institution in the last 5 years that shared in common the characteristic focal dorsal indentation of the spinal cord. RESULTS: Of 7 cases identified, all but 1 were treated and confirmed intraoperatively. All lesions were located at the dorsal spinal cord. Magnetic resonance imaging was the study of choice for evaluation. Clinical manifestations included back pain and lower extremity numbness and weakness together with compressive myelopathy signs and urinary symptoms. Mean follow-up was 16.8 months with satisfactory postoperative results. CONCLUSIONS: Isolated radiological presentation of the scalpel sign is not sufficient to distinguish between dorsal arachnoid webs, arachnoid cysts, and ventral herniation of the spine. However, awareness of its importance is relevant for accurate curative surgical planning.

Cervical laminoplasty with unilateral C4-5 foraminotomy: Technical note and case series.

OBJECTIVE: The open-door laminoplasty technique is widely used in the treatment of multilevel cervical myelopathy. Despite the satisfactory functional and radiological results of this technique, postoperative C5 palsy is still a severe and disabling complication with a variable incidence in the literature. The objective of this article is to describe and demonstrate the surgical technique step by step with the addition of unilateral C4-5 foraminotomy and to evaluate the results obtained to date, with special emphasis on C5 palsy. MATERIAL AND METHODS: Retrospective study of 20 patients operated on for cervical myelopathy using the "extended" laminoplasty technique, which is described step by step. RESULTS: Between January 2013 and April 2019, 20 patients were operated on using the extended laminoplasty technique. Only one patient (5%) presented postoperative C5 palsy. The postoperative recovery rate of the modified JOA (Japanese Orthopaedic Association) score was 54.5%, similar to that observed in other series. CONCLUSION: The extended cervical laminoplasty technique with unilateral C4-5 foraminotomy was developed and demonstrated for the prevention of C5 palsy. The results were analysed and an incidence of C5 palsy coinciding with the lowest percentage reported in the literature was obtained. A prospective randomised study would be useful to assess the role of preventive unilateral C4-5 foraminotomy.

"Este caso me desorientó... " / "This case disoriented me..."

Paciente masculino de 66 años que se presentó al servi-cio de guardia y urgencias por cuadro clínico caracteriza-do por mareos de 3 meses de evolución e inestabilidad de la marcha de 24 hs de evolución. Como único signo positi-vo al examen físico se constató dismetría de miembros su-periores. Se decidió estudiar con TC de cerebro en donde se identificó, en topografía pineal y tercer ventrículo, una voluminosa lesión ocupante de espacio, sólida, de aproxi-madamente 27 x 21 mm de densidad heterogénea, con pro-bable relación a restos hemáticos en distintos estadios evo-lutivos asociada a calcificaciones periféricas

Results in the treatment of intracranial hemangiopericytomas. Case series. / Resultados en el tratamiento de los hemangiopericitomas intracraneanos. Serie de casos.

OBJECTIVE: Intracranial hemangiopericytoma (HPC) is a rare central nervous system tumor characterized by its low incidence, high rate of local recurrence and risk of metastasis. The main objectives of this paper are two: to show the results in the treatment of HPC in our institution in the last 20years and to make a review of the literature on this topic. METHODS: Retrospective review that includes patients diagnosed with intracranial solitary fibrous tumor/hemangiopericytoma (SFT/HPC) that have undergone surgery from 1997 to 2017. It includes patients that had nuclear expression of STAT-6 (detected by immunohistochemistry) and gradeII/III histopathological diagnosis (defined by the World Health Organization in 2016). We collected demographic data, tumor characteristics, treatment and survival of these patients. RESULTS: A total of 19 patients fulfilled inclusion criteria. The median follow up was 96 months (12-230). The mortality rate was 21% (n=4). 57.9% of patients presented at least one tumor recurrence (n=11) (recurrences of 6%, 67% y 90% at 1, 5 and 10years). Five patients presented extracranial metastasis. Patients with tumors <6cm had greater survival (P<.05). CONCLUSIONS: A series of patients undergoing SFT/HPC were presented according to the new WHO criteria. Size is a predictor of survival. Currently there are no validated criteria for surgical resection in this pathology. A classification with surgical guidance would be useful.

Endoscopic resection through a retrosigmoid transmeatal approach of a large-sized vestibular schwannoma: operative video and technical nuances.

Surgical management of vestibular schwannomas has improved over the last 30 years. Whereas in the past the primary goal was to preserve the patient's life, today neurological function safeguarding is the main objective, with numerous strategies involving single resection, staged resections, postoperative radiosurgery, or single radiosurgery. The retrosigmoid approach remains the primary pathway for surgical access to the cerebellopontine angle (CPA). The use of an endoscope has great advantages. It contributes to the visualization and resection of residual tumor and also reduces the need for cerebellar retraction. The authors present a fully endoscopic resection of a large-sized vestibular schwannoma with facial nerve preservation. The video can be found here: https://stream.cadmore.media/r10.3171/2021.7.FOCVID21106.

Thalamic tumors in children: case series from our institution and literature review.

PURPOSE: To describe a case series of children with thalamic tumors treated at our institution in a 5-year period. METHOD: A retrospective and observational study was performed. The records of 15 patients between 2013 and 2018 were analyzed. RESULTS: From 2013 to 2018, 15 patients were treated at our institution. The male to female index was 1.5, and the median age was 8.9 (IQR 4.75-13). Seven (46%) tumors were left-sided, seven (46%) were right-sided, and one (6%) was bilateral. All patients were symptomatic at the time of treatment. Motor deficit was the most common form of presentation (73%). Gross-total resection was performed in two (13.3%) patients, subtotal resection was performed in two other patients (13.3%), and for the rest of the patients (73.3%), the chosen surgical approach was a stereotactic-guided biopsy. The average of procedures was 3.4, mostly related to the treatment for hydrocephalus. Twelve patients (80%) received treatment for hydrocephalus. Nine patients (75%) were treated with ventriculoperitoneal shunts, and four patients (33%) underwent endoscopic third ventriculostomy. High-grade tumors predominated. Grade IV tumors were diagnosed in six patients (40%), followed by grade III in four patients (26.6%), grade II in three (20%) patients, and grade I in two (13.3%) patients. Chemotherapy was given in 93% of the cases, being temozolomide, the most used drug. CONCLUSION: The clinical and surgical approaches for thalamic tumors in children have changed over time. At our institution, the lesser invasive surgical procedures are now being used more frequently.

Cervical laminoplasty with unilateral C4-5 foraminotomy: Technical note and case series. / Laminoplastia cervical con foraminotomía unilateral C4-C5: nota técnica y serie de casos.

OBJECTIVE: The open-door laminoplasty technique is widely used in the treatment of multilevel cervical myelopathy. Despite the satisfactory functional and radiological results of this technique, postoperative C5 palsy is still a severe and disabling complication with a variable incidence in the literature. The objective of this article is to describe and demonstrate the surgical technique step by step with the addition of unilateral C4-5 foraminotomy and to evaluate the results obtained to date, with special emphasis on C5 palsy. MATERIAL AND METHODS: Retrospective study of 20 patients operated on for cervical myelopathy using the "extended" laminoplasty technique, which is described step by step. RESULTS: Between January 2013 and April 2019, 20 patients were operated on using the extended laminoplasty technique. Only one patient (5%) presented postoperative C5 palsy. The postoperative recovery rate of the modified JOA (Japanese Orthopaedic Association) score was 54.5%, similar to that observed in other series. CONCLUSION: The extended cervical laminoplasty technique with unilateral C4-5 foraminotomy was developed and demonstrated for the prevention of C5 palsy. The results were analysed and an incidence of C5 palsy coinciding with the lowest percentage reported in the literature was obtained. A prospective randomised study would be useful to assess the role of preventive unilateral C4-5 foraminotomy.

Hemihypoglossal-Facial Nerve Transfer: Technical Description and Key Points: 2-Dimensional Operative Video.

Irreversible facial palsy, generally post-traumatic or postsurgical, can have devastating consequences for the patient from a functional, aesthetic, and psychological point of view. Among all of the reconstructive techniques, the hemihypoglossal-facial nerve transfer, which avoids the complete section of the hypoglossal nerve, is preferred by senior authors because of its excellent results and very low morbidity.1-5 This technique can be carried out in any neurosurgical center because it requires only basic instruments of microsurgery and a high-speed drill. However, detailed knowledge of the anatomy of the facial nerve in both its intrapetrosal and extracranial segments and of the hypoglossal nerve in its cervical segment is essential.1,6,7 Thus, previous practice in a cadaveric laboratory is recommended. The purpose of this video is to describe the technical nuances and key points of hemihypoglossal-facial nerve transfer. It was made using the surgical videos of 5 patients with a complete and irreversible facial paralysis who were operated using this technique in our institution between May and September 2019, all of whom consented to the procedure and to use for scientific purposes. The footages were edited, making a film in which the surgical technique is described in a stepwise fashion, emphasizing its most important features. To conclude, we would like to emphasize that the timing of surgery is of utmost importance and that this technique is both effective and reliable. Figures in the video at 00:54 and 01:35 are reprinted by permission from CCC: Springer Nature, Acta Neurochirurgica, Treatment of complete facial palsy in adults: comparative study between direct hemihypoglossal-facial neurorrhaphy, hemihipoglossal-facial neurorrhaphy with grafts, and massater to facial nerve transfer. Socolovsky M, Martins RS, di Masi G, Bonilla G, Siqueira M, vol 158, 945-957, copyright 2016.

Postcraniectomy pain: comparison between 2 incisions for the retrosigmoid approach. Prospective randomized study. / Dolor poscraniectomía: comparación entre 2 incisiones para el abordaje retrosigmoideo. Estudio prospectivo aleatorizado.

BACKGROUND: Suboccipital lateral approach is a common practice in neurosurgery to expose the region of the cerebellopontine angle. Postcraniectomy headache (PCH) is one of the most frequent complications that diminish the quality of life of patients. OBJECTIVE: To compare postcraniectomy pain in patients operated on for vestibular neurinomas by a suboccipital lateral approach by 2 different incisions. MATERIAL AND METHODS: Prospective randomized research study. Follow-up of patients operated for vestibular neurinomas between July 2017 and May 2019 (n=40) by the same surgeon. One group received the classical linear incision (n=20) and another group the alternative incision in an inverted "U" (modified Dandy) (n=20). Pain intensity was evaluated by numerical scale. A minimum follow-up of 3 months was carried out. The impact on quality of life was measured by the SF-36 questionnaire short version both before and after surgery. RESULTS: The average age was 46.1 years. The overall PCH index was 27.5% (n=11) of the patients. The incidence of pain in the group that received the classical incision (A) was 20% (n=4) and in group B was 35% (n=7). CONCLUSIONS: We found a higher rate of post-craniectomy headache in patients who underwent a "modified Dandy" incision. These are preliminary data of an undergoing study and we hope to obtain more representative information in the future. We recommend interdisciplinary follow up for the integral treatment of PCH.

Asistencia Endoscópica en la Descompresión Microquirúrgica del Hemiespasmo Facial / Endoscopic Assistance in Microsurgical Decompression of Facial Hemiespasm

Introducción: El hemiespasmo facial primario (HFP) se produce por la hiperexcitabilidad del nervio facial y sus núcleos de origen como consecuencia de la compresión vascular. La cirugía de descompresión neurovascular se plantea como alternativa al tratamiento médico refractario. Objetivos: Presentar nuestra experiencia respecto a esta patología. Material y métodos: Se realizó una revisión retrospectiva de pacientes operados por HPF refractarios a tratamiento médico en nuestra institución en los últimos 5 años (periodo 2014-2019). Todos fueron intervenidos vía retrosigmoidea. Se evaluaron datos demográficos, evaluación prequirúrgica y evolución postoperatoria. Resultados: Se operaron 4 pacientes bajo técnica microquirúrgica asistido por endoscopía. Edad promedio 52 años (rango 41-61) con una relación femenino masculino 3:1. El 25% (n=1) presentaba paresia facial grado 2 (HB) en el prequirúrgico. No hubo cambios en cuanto al grado de paresia facial en el postoperatorio en ningún caso. Sólo un paciente registró caída leve en la audiometría postquirúrgica. El 75% (n=3) resolvieron el HFP. Conclusión: Si bien nuestra serie es acotada a un número reducido de pacientes, la cirugía descompresiva microvascular es efectiva como alternativa al tratamiento médico refractario del HFP.

Introduction: Primary hemifacial spasm (PHS) is defined as the hyper excitability of the nerve due to the compression of the facial nerve or its nuclei, most commonly by a vascular structure. The surgical indication for microvascular decompression is resistance to pharmacological treatment or severe adverse effects. Objectives: To present our experience in the surgical treatment of this pathology with this novel technique. Materials and methods: We retrospectively reviewed all patients (n=4) with a diagnosis of PHS, who underwent endoscope-assisted microvascular decompression surgery in our institution during the last 5 years. In all the cases, we choose the retrosigmoid approach. We evaluated demographic data, preoperative evaluation, and post-operative evolution. Results: Endoscope-assisted microvascular decompression was the surgical technique in all the patients. The median age was 52 years, the female-male ratio of 3:1. Only one patient presented a grade 2 facial palsy (House-Brackmann scale) in the preoperative evaluation; there were no significant changes in the post-operative evaluation in any patient. Only one patient experienced worsening in the post-operative audiometric follow-up. The 75% (n=3) of the patients solved the HFP after the surgical treatment. Conclusion: By taking into account our experience in this small case series, we can support the concept that endoscope-assisted microvascular decompression is as effective as the open surgical treatment of the PHS.

[Placement of ventricle peritoneal shunt in the adult patient. A new protocol]. / Implante de shunt ventrículo peritoneal en el paciente adulto. Un nuevo protocol.

INTRODUCTION: Ventriculoperitoneal shunting is considered a relatively straightforward procedure, though it might ensure multiple complications. Our surgical team developed and implemented a new protocol since June 2016. The objective of this paper is to describe and illustrate the surgical technique step by step and to demonstrate that the use of the "new protocol" significantly reduces the complications associated with the procedure. METHODS: A retrospective descriptive study of 184 patients related with cerebrospinal fluid derivation systems from June 2014 to November 2017. One hundred and fourteen patients complied with the inclusion criteria. They were divided into two groups according to the protocol involved, previous (n = 59) and new (n = 55). The technique was described by photographic archive and surgical protocols. RESULTS: The technique consisting in seven phases was described. With the used of the new protocol the complications decreased significantly. After the new protocol, no ventriculoperitoneal shunt associated infections were observed. CONCLUSION: The technique for ventriculoperitoneal shunt consisting in seven phases was described thoroughly. This technique as well as a series of rules constitutes the new protocol. The implementation of the latter lessened the number of complications associated with the procedure. The "zero infection" rate is not a utopia.