The transcondylar approach to craniocervical meningiomas.

Surgical removal of foramen magnum meningiomas poses great challenges due their deep location within the central skull base and their proximity to vital neurovascular structures. This video depicts the operative nuances of surgical management for a 59-year-old female who presented with a right-sided spinocranial meningioma. Simpson Grade I resection was achieved through a right transcondylar approach. The patient's postoperative period was unremarkable, and she was discharged home on postoperative Day 5 for periodic follow-up. The transcondylar approach safely exposes the craniocervical junction at the anterior aspect of the neuraxis and still allows the surgeon to access the tumor through a parallel plane, with minimum morbidity. The video can be found here: https://youtu.be/P0-kXjAkw9U .

Microsurgical management of a high-grade brain arteriovenous malformation in the central lobe after unsuccessful radiosurgery.

The recommendation for the great majority of high-grade brain arteriovenous malformations (bAVMs) is observation, except for those patients with recurrent hemorrhages, progressive neurological deficits, steal-related symptoms, or AVM-related aneurysms, for whom intervention should be considered. These are general recommendations, and the decision should be made on an individual basis. Surgical resection of an AVM in the central lobe may cause postoperative sensorimotor deficits since this anatomical region includes the pre- and postcentral gyri on the lateral surface and the paracentral lobule on the medial surface. The authors present a patient with a ruptured high-grade bAVM in the central lobe who underwent previous surgery for hematoma evacuation and previous radiosurgery, and whose indication for reoperation was proposed based on progressive hemiparesis. Microsurgical resection was possible after a wide frontoparietal craniotomy, which made all the nidus borders accessible. This case illustrates the anatomy and surgical technique for large nidus AVMs in eloquent areas, showing that complete microsurgical resection is possible with good clinical outcome. The video can be found here: https://youtu.be/Cpd1PK6BLIM .

Quantitative non-nutritive sucking measurement as a predictor of oral feeding readiness in newborns.

Background and purpose: The purpose of this study is to examine the relationship between the parameters of a silver nanowire-based flexible pressure sensor developed to measure the non-nutritive sucking (NNS) performance and predict the nutritive sucking status in preterm infants. Methods: Preterm infants who were referred for feeding difficulty during the transition period from tubal feeding to oral feeding were enrolled in our study. A flexible pressure sensor was used to measure the non-nutritive sucking parameters of neonates. The evaluator stimulated the infants' lips and tongue with a pacifier integrated with a sucking pressure sensor, to check whether non-nutritive sucking had occurred. When the sucking reflex was induced, it was measured. The infants' sucking characteristics were subdivided into classifications according to the NOMAS criteria and full oral feeding (FOF) status. Quantitative NNS measurement according to the feeding state was compared between groups. Results: When comparing the quantitative NNS measurement by feeding characteristics, the average sucking pressure was significantly higher in infants in the FOF capable group than those in the incomplete FOF group. In addition, the maximum and average sucking pressure was significantly higher in infants with a normal sucking pattern compared to those with a disorganized sucking pattern. The average NNS pressure was divided over the range of 0-3 kPa and the same weight was assigned to each item. When the optimal cut-off value for the sensitivity and specificity of the average NNS pressure to estimate the FOF was set, a pressure of 1.5 kPa yielded the highest sensitivity (84.62%) and specificity (67.65%) on the receiver operating characteristic (ROC) curve. The area under the curve (AUC) was 0.786, and this result was statistically significant. Conclusions: This study presents a quantitative parameter for non-nutritive sucking in preterm infants with the use of a flexible pressure sensor. Results show possible quantitative indicators that can aid in predicting when preterm infants can transition to oral feeding and their prognosis. This will serve as a basis for future research on determining the feeding transition period of newborns with health conditions that affect oral feeding.

Case Report: Esthesioneuroblastoma Involving the Optic Pathways.

Olfactory neuroblastoma, or esthesioneuroblastoma, is an uncommon malignant tumor originating from the neural crest that commonly occurs in the upper nasal cavity. Its ectopic origin is extremely rare, especially when located in the optical pathways. This paper reports the case of a giant ectopic esthesioneuroblastoma of the optic pathways that were surgically treated through a cranio-orbital-zygomatic (COZ) craniotomy with extensive resection, in addition to a literature review. The patient is a 46-year-old female presenting with a 4-month history of visual loss in the left eye. Since she was previously blind in the right eye from a traumatic injury, it was evolving to loss of bilateral vision. Imaging depicted an expansive infiltrating lesion involving the entire path of the right optic nerve, extending to the optic chiasm, cisternal portion of the left optic nerve, bilateral optic tract, and hypothalamus. Investigation of pituitary function was unremarkable. Esthesioneuroblastoma is a rare tumor with poorly defined standard clinical management. Its ectopic presentation makes the diagnosis even more challenging, making it difficult to manage these cases properly. Surgeons should be aware of this rare possibility, as early aggressive treatment is likely to be associated with better results.

Anterior Transpetrosal Approach and Microsurgical Resection of a Petrous Tentorial Meningioma: 3-Dimensional Operative Video.

Tentorial meningiomas are challenging tumors because of its complex relationship with vital neurovascular structures. We present the case of a 41-yr-old female with a history of right-sided facial numbness associated with pain around the ear. Magnetic resonance imaging demonstrated a lesion in the right tentorium edge closely related with the porus trigeminus, suggestive of a meningioma. Because of worsening of symptoms the patient underwent surgery for tumor removal. A standard temporo-zygomatic craniotomy was performed, followed by an extradural peeling of the middle fossa; the petrous apex was drilled allowing access to the posterior fossa dura. Dural opening was carried connecting the temporal and posterior fossa, and the tentorium was then cut to the incisura. The tumor was identified and completely removed reaching Simpson grade I resection. Postoperatively, the patient presented a right dry eye in the first days that fully improved, and also a right-sided facial paralysis (House-Brackmann grade IV) and diplopia, both recovered completely after 4 mo. We believe that facial paralysis was the result of an undesired traction of the geniculate ganglion, or upon the nerve itself. To avoid such complication, dissection over the GSPN must be carried parallel to that nerve. Facial numbness and pain improved with no neurological other deficits. Tentorial meningiomas are complex deep-seated lesions that can be successfully approached through an anterior transpetrosal route in selected cases. Informed consent was obtained from the patient for publication of this operative video. Anatomical images were a courtesy of the Rhoton Collection, American Association of Neurological Surgeons/Neurosurgical Research and Education Foundation.

Intracranial aneurysms presenting with mass effect over the anterior optic pathways: neurosurgical management and outcomes.

OBJECT: Intracranial aneurysms may grow closer to anterior optic pathways, causing mass effect over these anatomical structures, including visual deficit. The authors retrospectively reviewed a series of aneurysms in patients presenting with visual field deficit caused by mass effect, to analyze the aneurysm's characteristics, the neurosurgical management of these aneurysms, as well as their clinical, visual, and radiological outcomes. METHODS: The authors reviewed the medical charts, neuroimaging examination results, and surgical videos of 15 patients presenting with visual symptoms caused by an aneurysm's mass effect over the anterior optic pathways. These patients were treated at the Department of Neurosurgery, Center of Neurology and Neurosurgery Associates, Hospital Beneficência Portuguesa de São Paulo, Brazil. Statistical analysis was performed to identify the variables related to partial or total recovery of the visual symptoms. RESULTS: All patients underwent microsurgical clip placement and emptying of their aneurysms. After a mean follow-up of 38.5 months, the mean postoperative Glasgow Outcome Scale score was 4.33, and the visual outcomes were as follows: 1 patient (6.6%) unchanged, 7 (46.6%) improved, and 7 (46.6%) experienced complete recovery from visual deficits. The variables that influenced the visual outcomes were the size of the aneurysm (p = 0.039), duration of the visual symptoms (p = 0.002), aneurysm wall calcification (p = 0.010), and intraluminal thrombosis (p = 0.007). Postoperative examination using digital subtraction angiography showed complete aneurysm occlusion in 14 (93.3%) of the 15 patients. CONCLUSIONS: Intracranial aneurysms causing mass effect over the anterior optic pathways usually present with complex features. The best treatment option must include not only the aneurysm occlusion but also relief of the mass effect. Microsurgical clip placement with reduction of aneurysmal mass effect achieved improvement in visual ability or recovery from visual impairment, as well as total aneurysm occlusion, in 93.3% of the study group. Therefore, this option is well supported as the first choice of treatment for intracranial aneurysms presenting with mass effect over the anterior visual pathways.

A rare anomaly of the anterior communicating artery complex hidden by a large broad-neck aneurysm and disclosed by three-dimensional rotational angiography.

Double fenestration of the anterior communicating artery (ACoA) complex associated with an aneurysm is a very rare finding and is usually caused by ACoA duplication and the presence of a median artery of the corpus callosum (MACC). We present a patient in whom double fenestration was not associated with ACoA duplication or even with MACC, representing therefore, a previously unreported anatomic variation. A 43 year old woman experienced sudden headache and the CT scans showed subarachnoid haemorrhage (SAH). On admission, her clinical condition was consistent with Hunt and Hess grade II. Conventional digital subtraction angiography (DSA) was performed and revealed multiple intracranial aneurysms arising from both middle cerebral arteries (MCA) and from the ACoA. Three-dimensional rotational angiography (3D-RA) disclosed a double fenestration of the ACoA complex which was missed by DSA. The patient underwent a classic pterional approach in order to achieve occlusion of both left MCA and ACoA aneurysms by surgical clipping. The post-operative period was uneventful. A rare anatomical variation characterised by a double fenestration not associated with ACoA duplication or MACC is described. The DSA images missed the double fenestration which was disclosed by 3D-RA, indicating the importance of 3D-RA in the diagnosis and surgical planning of intracranial aneurysms.

Surgical Approaches to the Temporal Horn: An Anatomic Analysis of White Matter Tract Interruption.

BACKGROUND: Surgical access to the temporal horn is necessary to treat tumors and vascular lesions, but is used mainly in patients with mediobasal temporal epilepsy. The surgical approaches to this cavity fall into 3 primary categories: lateral, inferior, and transsylvian. The current neurosurgical literature has underestimated the interruption of involved fiber bundles and the correlated clinical manifestations. OBJECTIVE: To delineate the interruption of fiber bundles during the different approaches to the temporal horn. METHODS: We simulated the lateral (trans-middle temporal gyrus), inferior (transparahippocampal gyrus), and transsylvian approaches in 20 previously frozen, formalin-fixed human brains (40 hemispheres). Fiber dissection was then done along the lateral and inferior aspects under the operating microscope. Each stage of dissection and its respective fiber tract interruption were defined. RESULTS: The lateral (trans-middle temporal gyrus) approach interrupted "U" fibers, the superior longitudinal fasciculus (inferior arm), occipitofrontal fasciculus (ventral segment), uncinate fasciculus (dorsolateral segment), anterior commissure (posterior segment), temporopontine, inferior thalamic peduncle (posterior fibers), posterior thalamic peduncle (anterior portion), and tapetum fibers. The inferior (transparahippocampal gyrus) approach interrupted "U" fibers, the cingulum (inferior arm), and fimbria, and transected the hippocampal formation. The transsylvian approach interrupted "U" fibers (anterobasal region of the extreme capsule), the uncinate fasciculus (ventromedial segment), and anterior commissure (anterior segment), and transected the anterosuperior aspect of the amygdala. CONCLUSION: White matter dissection improves our knowledge of the complex anatomy surrounding the temporal horn. Identifying the fiber bundles at risk during each surgical approach adds important information for choosing the appropriate surgical strategy.

Neurosurgical management of cerebellar cavernous malformations.

OBJECT: The aim of this study was to analyze cerebellar cavernous malformations (CMs) with respect to epidemiological, clinical, radiological, and therapeutic aspects. METHODS: Between 1984 and 2004, 100 patients were surgically treated for intracranial CMs at the Division of Neurosurgery of Federal University of Sao Paulo. The authors reviewed the records of 10 patients whose lesions were located in the cerebellum. There were four male and six female patients (ratio 1:1.5) whose ages ranged from 14 to 45 years (mean age 33 years). Clinical presentation was sudden or acute in all cases, and neuroimaging examinations performed in all patients demonstrated signs of bleeding. The mean size of the malformations was 4.6 cm, and in all but one patient the lesions were totally removed without complications. After a mean follow-up period of 70 months, all patients were considered to be in good or excellent clinical condition. CONCLUSIONS: Cerebellar CMs should be analyzed separately from other posterior fossa CMs. These lesions can reach large sizes and cause massive hemorrhages, resulting in acute or sudden presentation. Surgery is a safe and effective option that provides a curative treatment when a complete removal is achieved.

Predictors of Outcome in Nontraumatic Spontaneous Acute Spinal Subdural Hematoma: Case Report and Literature Review.

OBJECTIVES: To analyze the clinical presentation and outcome of nontraumatic spontaneous acute spinal subdural hematoma by observing the predictors of outcome. METHODS/RESULTS: This study was based on a case report and systematic review of the international literature. Among the 151 patients, 80 were female and 65 were male (1.25 female/1.0 male). The age distribution ranged from 6 months to 87 years, with a small increase in incidence between the first and second decade of life and a major peak at age 60 years. The difference of proportion of good results between patients with and without established neurologic deficits was: 0.488, 95% confidence interval (95% CI) 0.237-0.648, P = 2.71e-08; coagulopathy was 0.335, 95% CI 0.163-0.508, P = 0.0002; SAH was 0.0539, 95% CI -0.119 to 0.226, P = 0.6529; lumbar puncture/associated diseases was 0.149 95% CI -0.032 to 0.330, P = 0.1171; surgery was 0.0593, 95% CI -0.114 to 0.233, P = 0.5838; and hematoma extension equal or longer than 5 levels was 0.010 95% CI -0.178 to 0.197, P = 1. CONCLUSIONS: Although mortality and morbidity associated with nontraumatic spontaneous acute spinal subdural hematoma has decreased during the last 2 decades, the disease still carries a mortality rate of approximately1.3% and a morbidity (permanent neurologic deficits) rate of 28%. The main factors affecting the outcome are neurologic status at presentation and coagulopathies.

Spinal surgery for degenerative lumbar spine disease: Predictors of outcome.

OBJECTIVES: Identify predictors of outcomes for results in Degenerative Lumbar Spine Disease (DLSD). PATIENTS AND METHODS: A retrospective analysis of 164 patients who underwent surgery for DLSD was performed. The study duration was 24 months (January 2013-December 2014). The patients were first evaluated and were assessed for their results regarding the extent of surgery in four groups: patients undergoing surgery for treatment of one segment, two segments, three segments, and four or more segments of DLS. Posteriorly, the same group of patients was divided based on the presence or absence of Dural Tear (DT) during surgery. In addition, the relationship between elderlies and the incidence of surgical site infection (SSI) and reoperation was also analyzed. RESULTS: A total of 193 surgeries were performed on 164 patients (74 males/90 females), with a mean age of 53.18 years old (53.18 ± 17.54). SSI occurred in 7.31% of cases and re-operations due to SSI or because of complications resulting from the first procedure occurred in 11,58% of cases. Results statistically significant were found regarding the incidence of SSI (P=0.05) and the rate of re-operation (p=0.003) in surgeries involving more than three segments. DT is directly related to the rate of re-operation (p=0.0172) and SSI (p=0.0002). Elderly patients were not a predictor of poor outcome, neither to incidence of SSI (p=0.2), nor chance of re-operation (p=0.36). CONCLUSION: Surgeries involving more than three segments are directly related to SSI, incidence of accidental DT and chance of re-operation. The presence of DT during the procedure is presented as a predictor of postoperative SSI and an increase in re-operation rate. Furthermore, elderly patients are not related to a higher risk for SSI and re-operations.

Neurosurgical Management of Nonmissile Penetrating Cranial Lesions.

OBJECTIVE: The objective of this study is to present a case series of nonmissile penetrating (NMP) injuries and to establish a workflow for an uncommon mechanism of traumatic head injury through the analysis of each case, classification of the type of lesion, management, and outcome score at follow-up. METHODS: From January 1991 to December 2008, 36,000 patients presenting with traumatic brain injury (TBI) were admitted in the Department of Neurosurgery, Hospital Antônio Targino, Campina Grande-PB, Brazil. From these patients, 11 presenting with lesions caused by NMP objects were selected. RESULTS: Among the 11 patients, 9 were men and 2 were women. Their ages ranged from 7 to 74 years old (mean age ± SD, 29.1 ± 22.99 years). All patients underwent neuroradiologic evaluation. The entry point was classified as natural (orbit) or artificial (skull transfixation), and we also divided the patients presenting with secondary parenchymal or vascular damage from those presenting with only lesions caused by the primary penetration into the cranium and meninges. All patients were neurosurgically treated with removal of the foreign body through craniotomy, except the patient whose object (pen) was removed without craniotomy with local anesthesia. Glasgow Coma Scale (GCS) score on admission was a statistically significant factor on prognosis, and any patient who presented with a GCS score of 15 evolved satisfactorily, and there were no deaths in this group of patients (P = 0.04). CONCLUSIONS: TBIs caused by NMP objects are unusual and caused by aggression, self-inflicted harm (in the case of psychiatric patients), and accident. The foreign body may enter into the skull through a natural hole (orbit, nose, mouth, or ear) or crosses the skull, causing a fracture and creating an artificial hole. Preoperative neuroradiologic assessment is paramount for the correct neurosurgical approach. The main prognostic factor for these patients is the GCS score at admission.

Assessment of Cerebral Blood Flow with Micro-Doppler Vascular Reduces the Risk of Ischemic Stroke During the Clipping of Intracranial Aneurysms.

OBJECTIVE: To analyze the impact of the introduction of Micro-Doppler vascular (MDV) as a method of cerebral blood flow analysis during microsurgical clipping of intracranial aneurysms to check the partial occlusion of the aneurysm and the occurrence of stenosis by comparing these results with those provided by the postoperative digital subtraction angiography (DSA) scan as well as the occurrence of ischemic infarction on the postoperative computed tomography (CT) images. PATIENTS AND METHODS: We reviewed retrospectively the last 50 patients operated on before the introduction of the MDV (group 1) compared with the first 50 patients operated on using this technique (group 2). RESULTS: Nine (18%) of the 50 patients evaluated in the group 1 showed a new hypodensity in the postoperative CT images, whereas only 2 (4%) patients showed infarction in the group 2 (P = 0.02). In addition, in the group 1, 10 (20%) patients presented unexpected findings on DSA images (residual aneurysms, stenosis, and arterial occlusion), whereas in the group 2, those unexpected DSA findings were observed in only 3 (6%) patients (P = 0.023). CONCLUSION: MDV is an excellent method for cerebral blood flow assessment during the microsurgical clipping of intracranial aneurysms, reducing the unexpected angiographic results (residual aneurysms, stenosis, and arterial occlusion), as well as reducing the incidence of ischemic infarction on postoperative CT images, evidence of the positive impact of this method in the microsurgical treatment of intracranial aneurysms.

Impact of body mass index in spinal surgery for degenerative lumbar spine disease.

BACKGROUND: Obesity is a factor for degenerative lumbar spine disease (DLSD), with increasing prevalence worldwide. Consequently, patients who are overweight or obese have benefited from surgical treatment for DLSD, despite their anatomical and clinical differences. OBJECTIVES: To analyse the effect of body mass index (BMI) in spinal surgery for degenerative lumbar spine disease (DLSD). PATIENTS AND METHODS: A retrospective analysis of 100 patients who underwent surgery for DLSD was performed. The study time was 13 months (January 2013-January 2014). The patients were first evaluated with regard to their BMI and were subsequently divided into four groups of patients: BMI <25, BMI between 25 and 30, BMI between 30 and 35, and BMI above 35. The same patients were assessed for their results regarding the extent of surgery in four groups: patients undergoing surgery for treatment of one segment, two segments, three segments, and four or more segments of DLS. The aspects evaluated were surgical time, bleeding, surgical complications, surgical site infection (SSI), and re-operation due to failure of the first procedure. RESULTS: A total of 118 surgeries were performed on 100 patients (52 male/48 female), mean age 52.77 years old (52.77 ± 14.45), range between 26 and 85 years old, and a mean BMI of 29.43 kg/m(2) (29.43 ± 5.54). The surgical time averaged 258.1 min (258.1 ± 82.79); the bleeding was 660 millilitres (ml) (660 ± 509.1); complications that were related to the surgical procedure occurred in 38% of cases; SSI occurred in 5% of cases, and re-operations or SSI due to complications occurred in 12% of cases. After analysis of all variables, it was observed that the groups were homogeneous without statistical variation when divided by the BMI; however, it was also observed that the extent of surgery was the factor responsible for the increased rate of SSI (p=0.05) and increased potential of re-operation due to complications (p=0.003). CONCLUSION: BMI is not a complicating factor for the outcome of patients undergoing surgery for DLSD in terms of SSI, surgical complications, and re-operation rates. Furthermore, the extent of surgery was associated with increased postoperative SSI and the need for a second surgery due to the failure of the first procedure.

Supracerebellar transtentorial approach-resection of the tentorium instead of an opening-to provide broad exposure of the mediobasal temporal lobe: anatomical aspects and surgical applications: clinical article.

OBJECT: The aim of this study was to describe the surgical anatomy of the mediobasal aspect of the temporal lobe and the supracerebellar transtentorial (SCTT) approach performed not with an opening, but with the resection of the tentorium, as an alternative route for the neurosurgical management of vascular and tumoral lesions arising from this region. METHODS: Cadaveric specimens were used to illustrate the surgical anatomy of the mediobasal region of the temporal lobe. Demographic aspects, characteristics of lesions, clinical presentation, surgical results, follow-up findings, and outcomes were retrospectively reviewed for patients referred to receive the SCTT approach with tentorial resection. RESULTS: Ten patients (83%) were female and 2 (17%) were male. Their ages ranged from 6 to 59 years (mean 34.5 ± 15.8 years). All lesions (3 posterior cerebral artery aneurysms, 3 arteriovenous malformations, 3 cavernous malformations, and 3 tumors) were completely excluded or resected. After a mean follow-up period of 143 months (range 10-240 months), the mean postoperative Glasgow Outcome Scale score was 4.9. CONCLUSIONS: Knowledge of the surgical anatomy provides improvement for microsurgical approaches. The evolution from a small opening to a resection of the tentorium absolutely changed the exposure of the mediobasal aspect of the temporal lobe. The SCTT approach with tentorial resection is an excellent alternative route to the posterior part of mediobasal aspect of the temporal lobe, and it was enough to achieve the best neurosurgical management of tumoral and vascular lesions located in this area.

Advances in the treatment and outcome of brainstem cavernous malformation surgery: a single-center case series of 300 surgically treated patients.

BACKGROUND: Brainstem cavernous malformations (BSCMs) are relatively uncommon, low-flow vascular lesions. Because of their relative rarity, relatively little data on their natural history and on the efficacy and durability of their treatment. OBJECTIVE: To evaluate the long-term durability of surgical treatment of BSCMs and to document patient outcomes and clinical complications. METHODS: The charts of all patients undergoing surgical treatment of BSCM between 1985 and 2009 were reviewed retrospectively. The study population consisted of 300 patients who had surgery for BSCM. Forty patients were under 19 years of age at surgery; pediatric BSCMs have been reported separately. Patient demographics, lesion characteristics, surgical approaches, and patient outcomes were examined. RESULTS: The study population consisted of 260 adult patients with a female-to-male ratio of 1.5 and mean age of 41.8 years. Of the 260 patients, 252 presented with a clinical or radiographic history of hemorrhage. The mean follow-up in 240 patients was 51 months. The mean Glasgow Outcome Scale on admission, at discharge, and at last follow-up was 4.4, 4.2, and 4.6. Postoperatively, 137 patients (53%) developed new or worsening neurological symptoms. Permanent new deficits remained in 93 patients 3(36%). There were perioperative complications in 74 patients (28%); tracheostomy, feeding tube placement, and cerebrospinal fluid leakage were most common. Eighteen patients (6.9%) experienced 20 rehemorrhages. Twelve patients required reoperation for residual/recurrent BSCM. The overall annual risk of postoperative rehemorrhage was 2%/patient. CONCLUSION: Although BSCM surgery has significant associated risks, including perioperative complications, new neurological deficits, and death, most patients have favorable outcomes. Overall, surgery markedly improved the risk of rehemorrhage and related symptoms and should be considered in patients with accessible lesions.

Supracerebellar infratentorial approach to cavernous malformations of the brainstem: surgical variants and clinical experience with 45 patients.

OBJECTIVE: The supracerebellar infratentorial (SCIT) approach can be performed at the midline (median variant), lateral to the midline (paramedian variant), or at the level of the angle formed by the transverse and sigmoid sinuses (extreme lateral variant). We analyzed our experience with SCIT approaches for the surgical treatment of cavernous malformations of the brainstem (CMBs). METHODS: Demographic, clinical, radiologic, and surgical data from 45 patients (20 males and 25 females; mean age, 36.2 years) with CMBs surgically removed through SCIT approaches were reviewed retrospectively. Anatomic information was explored using cadaver head dissection. RESULTS: Twenty-three lesions were in the midbrain, 3 were at the midbrain and extended to the thalamus, 9 were at the pontomesencephalic junction, and 10 were in the upper pons. All patients presented with hemorrhage. The median variant was used in 13 patients, the paramedian variant in 9, and the extreme lateral variant in 23. Intraoperatively, all CMBs were associated with a developmental venous anomaly. At last follow-up, 88% of the patients were the same or better. After a mean follow-up of 20 months, their mean Glasgow Outcome Scale score was 4.1. CONCLUSION: SCIT approaches provide excellent exposure to CMBs located at the posterior incisural space, not only in the midline but also in the posterolateral surface of the upper pons and midbrain. Careful preoperative planning and neuronavigational assistance are needed to determine the best angle of attack and trajectory for SCIT approaches. Refined microsurgical techniques are paramount to achieve safe surgical removal of CMBs with good outcomes.

Surgical management of glomus jugulare tumors: a proposal for approach selection based on tumor relationships with the facial nerve.

OBJECT: The goal of this paper is to analyze the extension and relationships of glomus jugulare tumor with the temporal bone and the results of its surgical treatment aiming at preservation of the facial nerve. Based on the tumor extension and its relationships with the facial nerve, new criteria to be used in the selection of different surgical approaches are proposed. METHODS: Between December 1997 and December 2007, 34 patients (22 female and 12 male) with glomus jugulare tumors were treated. Their mean age was 48 years. The mean follow-up was 52.5 months. Clinical findings included hearing loss in 88%, swallowing disturbance in 50%, and facial nerve palsy in 41%. Magnetic resonance imaging demonstrated a mass in the jugular foramen in all cases, a mass in the middle ear in 97%, a cervical mass in 85%, and an intradural mass in 41%. The tumor was supplied by the external carotid artery in all cases, the internal carotid artery in 44%, and the vertebral artery in 32%. Preoperative embolization was performed in 15 cases. The approach was tailored to each patient, and 4 types of approaches were designed. The infralabyrinthine retrofacial approach (Type A) was used in 32.5%; infralabyrinthine pre- and retrofacial approach without occlusion of the external acoustic meatus (Type B) in 20.5%; infralabyrinthine pre- and retrofacial approach with occlusion of the external acoustic meatus (Type C) in 41%; and the infralabyrinthine approach with transposition of the facial nerve and removal of the middle ear structures (Type D) in 6% of the patients. RESULTS: Radical removal was achieved in 91% of the cases and partial removal in 9%. Among 20 patients without preoperative facial nerve dysfunction, the nerve was kept in anatomical position in 19 (95%), and facial nerve function was normal during the immediate postoperative period in 17 (85%). Six patients (17.6%) had a new lower cranial nerve deficit, but recovery of swallowing function was adequate in all cases. Voice disturbance remained in all 6 cases. Cerebrospinal fluid leakage occurred in 6 patients (17.6%), with no need for reoperation in any of them. One patient died in the postoperative period due to pulmonary complications. The global recovery, based on the Karnofsky Performance Scale (KPS), was 100% in 15% of the patients, 90% in 45%, 80% in 33%, and 70% in 6%. CONCLUSIONS: Radical removal of glomus jugulare tumor can be achieved without anterior transposition of the facial nerve. The extension of dissection, however, should be tailored to each case based on tumor blood supply, preoperative symptoms, and tumor extension. The operative field provided by the retrofacial infralabyrinthine approach, or the pre- and retrofacial approaches, with or without closure of the external acoustic meatus, allows a wide exposure of the jugular foramen area. Global functional recovery based on the KPS is acceptable in 94% of the patients.

The craniocaudal extension of posterolateral approaches and their combination: a quantitative anatomic and clinical analysis.

OBJECTIVE: The aim of this study was to describe quantitatively the properties of the posterolateral approaches and their combination. METHODS: Six silicone-injected cadaveric heads were dissected bilaterally. Quantitative data were generated with the Optotrak 3020 system (Northern Digital, Waterloo, Canada) and Surgiscope (Elekta Instruments, Inc., Atlanta, GA), including key anatomic points on the skull base and brainstem. All parameters were measured after the basic retrosigmoid craniectomy and then after combination with a basic far-lateral extension. The clinical results of 20 patients who underwent a combined retrosigmoid and far-lateral approach were reviewed. RESULTS: The change in accessibility to the lower clivus was greatest after the far-lateral extension (mean change, 43.62 +/- 10.98 mm2; P = .001). Accessibility to the constant landmarks, Meckel's cave, internal auditory meatus, and jugular foramen did not change significantly between the 2 approaches (P > .05). The greatest change in accessibility to soft tissue between the 2 approaches was to the lower brainstem (mean change, 33.88 +/- 5.25 mm2; P = .0001). Total removal was achieved in 75% of the cases. The average postoperative Glasgow Outcome Scale score of patients who underwent the combined retrosigmoid and far-lateral approach improved significantly, compared with the preoperative scores. CONCLUSION: The combination of the far-lateral and simple retrosigmoid approaches significantly increases the petroclival working area and access to the cranial nerves. However, risk of injury to neurovascular structures and time needed to extend the craniotomy must be weighed against the increased working area and angles of attack.

Surgical management of foramen magnum meningiomas.

The objective of the study is to describe our experience in the surgical management of foramen magnum meningiomas with regard to the clinical-radiological findings, the surgical approach and the outcomes after mid-term follow up. Over a 5-year period, 15 patients presenting with meningiomas of the foramen magnum underwent surgical treatment. The medical records were reviewed in order to analyze the clinical-radiological aspects, as well as the surgical approach and the outcomes. Based on the preoperative magnetic resonance imaging exams, the tumors were classified as anterior or anterolateral in the axial slices and clivospinal or spinoclival in the sagittal slices. The lateral approach was used in all cases. However, the extent of bone removal and the management of the vertebral artery were tailored to each patient. Fourteen patients were females, and one was male, ranging in age from 42 to 74 years (mean 55,9 years). The occipital condyle was partially removed in eight patients, and in seven patients, removal was not necessary. Total removal of the tumor was achieved in 12 patients, subtotal in two, and partial resection in one patient. Postoperative complications occurred in two patients. Follow-up ranged from 6 to 56 months (mean 23.6 months).There was no surgical mortality in this series. The extent of the surgical approach to foramen magnum meningiomas must be based on the main point of dural attachment and tailored individually case-by-case. The differentiation between the clivospinal and spinoclival types, as well as anterior and anterolateral types, is crucial for the neurosurgical planning of foramen magnum meningiomas.