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BACKGROUND: One-piece modified orbitozygomatic approach (OZA) is an extended version of the pterional approach that also includes orbital walls and frontal process of the zygomatic bone. For this craniotomy one burr hole must be placed in MacCarty keyhole and another - in the temporal region. OBJECTIVE: To develop a technique of the one-piece modified OZA with single a burr hole in the alternative sphenoid ridge keyhole that allows access to orbit, anterior cranial fossa and middle cranial fossa and apply it intraoperatively. METHODS: A single human head specimen was used. The dissection was performed using standard surgical instruments high-speed Stryker drill. Every stage of the approach was photographed. We also report a surgical case of a patient with orbital cavernous hemangioma that was resected using the described technique. RESULTS: The technique of the one-piece modified OZA with a single burr hole in the alternative sphenoid ridge keyhole is described, and its advantages and limitations are analyzed. The technique is used to totally resect an orbital cavernous hemangioma with good functional and cosmetic result. CONCLUSION: Modified OZA with a single burr hole in the sphenoid ridge keyhole is possible and may be an alternative to the classic technique. The advantages of this variation are the placement of just one burr hole and the preservation of a larger portion of the orbital roof. The latter facilitates better bone reconstruction and better cosmetic outcome. Disadvantages are the difficulty of identifying the location of the sphenoid ridge keyhole and risk of damaging the dura.
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Craneotomía , Hemangioma Cavernoso , Humanos , Craneotomía/métodos , Base del Cráneo/cirugía , Hueso Esfenoides/cirugía , Órbita/cirugía , Hemangioma Cavernoso/cirugíaRESUMEN
The pterional craniotomy with anterior clinoidectomy is a surgical technique used to resect sphenoid ridge meningiomas. It involves drilling the bone of the anterior clinoid process to gain access to the skull base, including the cavernous sinus and petrous apex particularly. This approach offers several advantages, including excellent exposure of the surgical site, minimal brain retraction, and the ability to visualize and protect critical neurovascular structures. We present a case of a 59-year-old woman presented with headache, dizziness, blurry vision, and unsteady gait for several months. The brain magnetic resonance imaging with gadolinium contrast showed a large space-occupying homogeneously-enhancing lesion at the left skull base, displacing the surrounding structures, including the frontal lobe, temporal lobe, and brainstem. Herein, we present the intraoperative video on a case in which the pterional craniotomy with anterior clinoidectomy that can allow the exposure and resection of the tumor extending into the posterior fossa was utilized for the resection of a large left sphenoid ridge meningioma with brain stem compression.
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BACKGROUND: Paraclinoid aneurysms represent a challenge for neurosurgeons due to the anatomical complexity of this region. Then, innovative techniques such as the extradural sphenoid ridge approach are suitable for a safe microsurgical clipping. METHOD: A description of the surgical technique was made by the senior author, a vascular neurosurgeon experienced with the use of this approach in the management of paraclinoid aneurysms exemplified through a clinical case. CONCLUSION: Microsurgical clipping through an extradural sphenoid ridge keyhole approach for small and midsize paraclinoid aneurysms is an excellent treatment modality with good clinical and surgical results.
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Aneurisma Intracraneal , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/cirugía , Procedimientos Neuroquirúrgicos/métodos , Microcirugia/métodos , Hueso Esfenoides/diagnóstico por imagen , Hueso Esfenoides/cirugíaRESUMEN
OBJECTIVE: To investigate the surgical method and efficacy of the extended pterional approach in the resection of huge medial sphenoid ridge meningiomas (MSRMs). METHODS: Retrospective analysis of clinical data from 41 patients diagnosed with MSRMs (diameter ≥4.0 cm) from Nanjing Brain Hospital between January 2012 and February 2022 was conducted. Within 24 hours after surgery, head computed tomography and magnetic resonance imagingwere reviewed to evaluate the extent of tumor resection based on Simpson grading. Cranial magnetic resonance imagingwas repeated 3 to 60 months after surgery to assess tumor recurrence or progression. Preoperative, discharge, and follow-up Karnofsky functional status scores (KPS) were assessed to determine patients' functional status. Repeated-measures analysis of variance was utilized to compare KPS at preoperative, hospital discharge, and final follow-up. RESULTS: The 41 selected cases included 38 cases (92.7%) of Simpson I-III resection and 3 cases (7.3%) of Simpson IV resection. All the cases had typical pathological features and definite pathological diagnoses. There were 2 recurrent tumors and 4 progressed tumors when the patients were followed up from 3 months to 60 months after operations. The results demonstrated that the KPS score at the final follow-up (91.4 ± 9.6) was higher than at hospital discharge (85.3 ± 8.9) and preoperation (78.2 ± 8.5) (F = 69.46, P = 0.033). CONCLUSIONS: The use of the extended pterional approach in the resection of huge MSRMs appears to be an effective surgical method. Careful dissection and preservation of vascular and neural structures, as well as meticulous microsurgical techniques in managing cavernous sinus tumors, can lead to reduced surgical complications and improved treatment outcomes.
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Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/diagnóstico por imagen , Meningioma/cirugía , Meningioma/complicaciones , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/cirugía , Neoplasias Meníngeas/complicaciones , Estudios Retrospectivos , Recurrencia Local de Neoplasia/cirugía , Recurrencia Local de Neoplasia/complicaciones , Resultado del Tratamiento , Procedimientos Neuroquirúrgicos/métodosRESUMEN
BACKGROUND: During the pterional-transsylvian approach, we sometimes encounter the proximal Sylvian fissure (SF) deviating laterally beyond the fold of the sphenoidal ridge (SR) and experience difficulty dissecting the SF due to the deep and oblique dissection plane. In the present study, we explored the association between the height of the SR and lateral deviation of the SF during the pterional-transsylvian approach. METHODS: The association between the height of the SR on axial computed tomography and the presence of a laterally deviated SF was evaluated by reviewing patients who had undergone pterional craniotomy. RESULTS: Among the 52 patients included, lateral deviation of the SF was observed in 8 patients (13.4%). The median height of the SR was significantly smaller in patients with laterally deviated SF (6.0 mm) than in patients with non-deviating SF (13.4 mm; P < 0.0001). The oculomotor nerves and middle fossa were observed at the edge of the dissection plane of the SF in all patients with a laterally deviating SF, while medial structures such as the internal carotid artery or optic nerve were observed in patients with non-deviating SF. CONCLUSIONS: Small SR was associated with lateral deviation of the proximal SF.
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Corteza Cerebral , Craneotomía , Humanos , Craneotomía/métodos , Corteza Cerebral/cirugía , Hueso Esfenoides/diagnóstico por imagen , Hueso Esfenoides/cirugía , Base del Cráneo/cirugía , Arteria Carótida Interna/cirugíaRESUMEN
Intracranially located teratomas usually involve midline brain structures. However, they rarely occur in adults. A 26-year-old woman presented with a growing intracranial mass lesion in the left sphenoid ridge without neurological deficits. Magnetic resonance imaging revealed homogenous hyperintensities without contrast enhancement. The patient underwent gross total excision of the soft, yellowish sphenoid ridge tumor with no cystic component. The surgery was uneventful, with no intraoperative complications. Histological analysis revealed a mature teratoma. She attended regular outpatient neuroradiology follow-up appointments. The present case is an unusual example of a mature teratoma with regard to location, neuroimaging appearance, macroscopic intraoperative findings, histological tumor subtype, and patient age and sex.
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Teratoma , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Teratoma/diagnóstico por imagen , Teratoma/cirugíaRESUMEN
BACKGROUND: Resection of giant sphenoclinoidal meningiomas (SCLM) remains difficult. We discuss a patient presenting with right eye near blindness who underwent total removal of a giant SCLM, resulting in normal vision and no recurrence. METHOD: Utilizing frontotemporal craniotomy, devascularization, debulking, and detachment was achieved. Microdissection of tumor off the optic nerve and carotid perforators was accomplished, resulting in total resection, visual normalization, and no deficits using efficient face-to-face microscope set-up, 2-surgeon 4-hand technique, and double bipolar-suction arrangement. CONCLUSION: Frontotemporal craniotomy was adequate. Preservation of the optic nerve and carotid artery is key. Meticulous microsurgical techniques and refined instruments are important for success.
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Neoplasias Meníngeas , Meningioma , Ceguera/etiología , Ceguera/cirugía , Humanos , Neoplasias Meníngeas/complicaciones , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/cirugía , Meningioma/complicaciones , Meningioma/diagnóstico por imagen , Meningioma/cirugía , Procedimientos Neuroquirúrgicos , Hueso Esfenoides , Resultado del TratamientoRESUMEN
BACKGROUND: We report a technique for the sphenoid ridge keyhole approach using the Lone Star (LS) retractor system as an extracranial tissue retractor in microsurgical clipping of unruptured middle cerebral artery aneurysms. METHODS: The LS retractor system is used as the extracranial tissue retractor. A skin incision (50-60 mm) without shaving is made. The temporal fascia is cut, and skin and fascia flap are reflected anteriorly. On the temporal muscle, keyhole craniotomy is registered using the navigation system such that the lateral edge of the sphenoid ridge is the center of the craniotomy. After the temporal muscle is split in the direction of the muscle fiber, keyhole craniotomy of approximately 30 mm in diameter is created. After dural incision, the Sylvian fissure is dissected by a standard microsurgical technique using brain retractors, and the target aneurysm is clipped. RESULTS: By precise registration of the sphenoid ridge keyhole craniotomy, the Sylvian fissure emerged in the center of the keyhole. Using the LS retractor system, a flat and shallow operative field was obtained. There were no complications using this method. CONCLUSIONS: We optimized the craniotomy, manipulating the target aneurysm in the center of the keyhole. It did not interfere with conventional microsurgical techniques.
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Craneotomía/métodos , Aneurisma Intracraneal/cirugía , Microcirugia/métodos , Hueso Esfenoides/cirugía , Humanos , Instrumentos QuirúrgicosRESUMEN
Background Of the minimally invasive "keyhole" alternatives to the pterional region, the supraorbital eyebrow approach is the most widely adopted. Yet it can prove disadvantageous when a more direct lateral microsurgical trajectory of attack to the Sylvian fissure and anterior middle fossa are needed. Objective The extended lateral orbital (XLO) approach was designed to be direct and minimally invasive, with the sphenoid ridge at the center of exposure. Methods Five injected cadaver heads were used for anatomic study of the XLO approach. The anatomic course of the frontalis branch of facial nerve was studied in relation to the XLO incision. Following XLO incision, the bone exposure was measured. The intracranial microsurgical exposure was assessed subjectively. Application of the technique in representative clinical operative cases is provided. Results The frontalis nerve was protected in the subgaleal fat pad, with an average minimum distance of 2.3 cm from the XLO incision. The mean calvarial area exposure was 4.95 cm 2 and consistently centered on the sphenoid ridge. Excellent access to ipsilateral Sylvian's fissure, perisylvian regions, and supra-/parasellar structures was possible. The main limitations related to exposure of the posterior Sylvian fissure and the expected limitations of microsurgical instrument manipulation from a smaller craniotomy. Conclusions The XLO approach is a minimally invasive keyhole approach to the pterional region that affords a unique lateral trajectory via a craniotomy centered on the sphenoid ridge. Excellent exposure to properly selected lesions is possible. The incision is at a safe distance from the frontalis branch and shows excellent cosmetic healing.
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OBJECTIVE: The superficial middle cerebral vein (SMCV) is of clinical importance because of its contribution to the venous drainage of the superficial part of the cerebrum. Sphenoid ridge meningioma (SRM) grows adjacent to the SMCV and its drainage routes, and is thought to occasionally influence the hemodynamics of the SMCV, although this has seldom been suggested in the literature. We investigated the effect of SRM on the SMCV via blood flow analysis using multi-detector computed tomography. PATIENTS AND METHODS: Overall, 22 patients with SRM who preoperatively underwent contrast-enhanced dynamic computed tomography at our institution were included in this study. We serially measured the Hounsfield units at each point of the SMCV and its adjacent veins on the side on which the tumor was located. We then obtained a time-density curve for each point via gamma distribution fitting. We determined the time-to-peak at each point by calculating the derivative of the time-density curve function and deduced the direction of blood passing through each vein by comparing the time-to-peak values between several points. RESULTS: In total, 26 SMCVs were measured in 19 out of 22 cases. Of the 26 SMCVs, 16 were patent in the medial portion and contributed to normal venous drainage: 4 of them emptied into the cavernous sinus (CS), and 12 of them into the para-cavernous sinus (ParaCS). Out of the 10 that had their medial portions occluded because of the effects of the tumor, 6 SMCVs mainly drained into the vein of Labbé and/or the vein of Trolard retrogradely. However, in 2 of these, the small medial portions of the SMCVs near the occluded portion were maintained anterogradely by the collateral venous structures. In 4 SMCVs, the blood flow through the collateral veins remained anterograde; this was considered to contribute to normal venous drainage. CONCLUSION: The SRM is likely to cause occlusion or stenosis in the SMCV and influence its hemodynamics. In cases in which the connection between the SMCV and the CS or the ParaCS has been lost, the SMCV may still be involved in normal venous drainage via the collateral veins in some of those cases. Thus, the contribution of these veins to normal venous drainage in the brain should be analyzed preoperatively in careful detail.
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Venas Cerebrales/diagnóstico por imagen , Hemodinámica/fisiología , Neoplasias Meníngeas/diagnóstico por imagen , Meningioma/diagnóstico por imagen , Adulto , Anciano , Angiografía Cerebral , Venas Cerebrales/fisiopatología , Circulación Cerebrovascular , Angiografía por Tomografía Computarizada , Constricción Patológica/diagnóstico por imagen , Constricción Patológica/etiología , Constricción Patológica/fisiopatología , Femenino , Humanos , Masculino , Neoplasias Meníngeas/complicaciones , Neoplasias Meníngeas/cirugía , Meningioma/complicaciones , Meningioma/cirugía , Persona de Mediana Edad , Tomografía Computarizada Multidetector , Hueso Esfenoides , Adulto JovenRESUMEN
BACKGROUND: Extracerebral neuroglial heterotopias are rare manifestations of cerebral tissue outside the brain whose most common form is the so-called nasal glioma. In this case report we illustrate the first case of heterotopic neuroglial tissue within the bone of the skull. CASE DESCRIPTION: Our patient underwent surgery for a sphenoid ridge meningioma. Aside from the expected meningioma, histopathologic examination showed a small amount of intraosseous heterotopic neuroglial tissue. CONCLUSIONS: The pathogenesis of cerebral heterotopias is diverse. Most of the midline lesions are probably residuals of former meningoencephaloceles. The pathogenesis of extracranial nonmidline lesions is more questionable. Their cause might be a former trauma, inflammatory disease, or surgery. Another option is that they represent primary neuroglial heterotopias, as it is supposed for manifestations of the lung. The coexistence of a heterotopia and a meningioma in this case is probably a coincidence. It is also debatable whether the broad tumor extension within the bone and/or the heterotopia might go back to alterations of the bone structure.
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Encéfalo , Coristoma/patología , Neoplasias Craneales/patología , Coristoma/cirugía , Craniectomía Descompresiva/métodos , Femenino , Humanos , Imagen por Resonancia Magnética , Neoplasias Meníngeas/patología , Neoplasias Meníngeas/cirugía , Meningioma/patología , Meningioma/cirugía , Persona de Mediana Edad , Invasividad Neoplásica , Neoplasias Craneales/cirugía , Hueso Esfenoides/patología , Hueso Esfenoides/cirugía , Tomografía Computarizada por Rayos X , Trastornos de la Visión/etiología , Trastornos de la Visión/patologíaRESUMEN
OBJECTIVE: Sphenoid wing meningiomas are the third most common group of intracranial meningiomas. Their management is a challenge because of their bone invasion potential and their proximity to neurovascular structures and the cavernous sinus. METHODS: A cohort of 141 patients with sphenoid wing meningioma who were operated on and followed up between 1986 and 2018 were retrospectively analyzed. Demographic data, clinical and radiologic features, surgical results, and follow-up data are presented. The effects of adjuvant treatments (radiosurgery, radiotherapy, and chemotherapy) are reviewed. The invasion pattern of tumors and other factors were noted to analyze the extent of resection. Recurrence/regrowth rates were also analyzed. RESULTS: There were 96 female and 45 male patients with a median age of 51 years (range, 17-87 years). The median follow-up was 62 months (range, 1-303 months). Tumors were grouped as spheno-orbital (31 patients), lateral (34 patients), middle (35 patients), and medial (41 patients). Gross total resection was achieved in 98 patients, and 43 tumors were resected subtotally. One hundred and twenty of these cases had World Health Organization grade I pathology, whereas the remainder had grade II. In the follow-up, there were 14 recurrences of totally resected tumors, and 24 regrowths were observed in the subtotally resected group. No invasion pattern was strongly predictive of extent of resection alone, and a scoring system was built up and proposed. CONCLUSIONS: Sphenoid wing meningioma is a large group with characteristics associated with skull base meningiomas and convexity meningiomas. The results of surgery and other adjuvant treatments are heterogeneous.
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Neoplasias Meníngeas/cirugía , Meningioma/cirugía , Neoplasias de la Base del Cráneo/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada , Femenino , Humanos , Masculino , Neoplasias Meníngeas/complicaciones , Neoplasias Meníngeas/patología , Meningioma/complicaciones , Meningioma/patología , Persona de Mediana Edad , Clasificación del Tumor , Recurrencia Local de Neoplasia/cirugía , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Radiocirugia/estadística & datos numéricos , Radioterapia Adyuvante/estadística & datos numéricos , Reoperación/estadística & datos numéricos , Estudios Retrospectivos , Neoplasias de la Base del Cráneo/complicaciones , Neoplasias de la Base del Cráneo/patología , Resultado del Tratamiento , Adulto JovenRESUMEN
Frontolateral craniotomy procedures have advanced from conventional craniotomy to mini-craniotomy, and to contemporary keyhole surgery. In this context, it is important for the neurosurgeon to precisely locate the pterion. The distance of the pterion center from midpoint of zygomatic arch and posterolateral margin of frontozygomatic suture was studied bilaterally in 50 whole adult skulls in Indian ethnic group. The depth of optic canal and sphenoid ridge from the pterion was recorded bilaterally in fifty cut adult skulls and fifteen three-dimensional computed tomography scans. The suture length, thickness, and morphology were studied. The data were analyzed using SPSS software, two-tailed Student's t test, binary logistic regression and receiver operating characteristic curve for sexual dimorphism. The pterion center was located at a mean distance of 37.02 mm above the midpoint of zygomatic arch, 28.20 mm behind the posterolateral margin of frontozygomatic suture, 42.73 mm lateral to the optic canal and 10.59 mm from the sphenoid ridge. The location did not exhibit sexual dimorphism. In 20% cases the pterion center was 40 mm or more above the midpoint of the zygomatic arch and in 5% cases 35 mm or more posterior to the posterolateral margin of frontozygomatic suture. The mean suture length was 10±3 mm. The mean thickness at the center of the pterion was 3.52±1.45 mm. The commonest variety was sphenoparietal followed by frontotemporal, epipteric, and stellate types. A thorough knowledge of these dimensions has innumerable neurosurgical implications in resection of sellar, parasellar, and paraclinoid tumors and circulatory aneurysms.
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Adulto , Humanos , Aneurisma , Neoplasias Encefálicas , Craneotomía , Etnicidad , Modelos Logísticos , Neurocirujanos , Curva ROC , Cráneo , Suturas , CigomaRESUMEN
PURPOSE: We have diagnosed 35 cases of the supposedly rare condition metopic-sagittal synostosis in the past 20 years. Here, we introduce their clinical symptoms, neuroradiological findings, and surgical treatment methods, as well as discuss the relevant literature. METHODS: Subjects included 35 patients (33 boys and 2 girls; mean age 4.2 years; range 1-8 years). Magnetic resonance imaging (MRI) confirmed that there were no abnormal findings in the brain. Thirty patients presented with symptoms including speech delay, hyperactivity, autistic tendency, motor impairment, self-mutilation, and panic/temper tantrum behaviors. No other congenital malformation was observed, and all cases were considered to be the non-syndromic type. The final diagnosis was made using three-dimensional computed tomography (3D-CT) scans. The surgery was done the fronto-orbital advancement in addition to remove the large parts of sphenoid bones including sphenoid ridges at the skull base and trimmed the calvarium as necessary to reduce pressure. RESULTS: Surgical intervention improved clinical symptoms in nearly all 35 patients; cosmetic problems in patients with scaphocephaly were also corrected. CONCLUSIONS: In the cases of child patients with metopic-sagittal synostosis who had clinical symptoms, surgical intervention improved such symptoms, suggesting its potential utility for metopic-sagittal synostosis with clinical symptoms. A surgical procedure focusing on the skull base was important for our successes. Based on the fact that metopic-sagittal synostosis was diagnosed in 35 patients at one institution over a relatively short period of time, this pathological condition may not be as rare as is currently believed.
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Craneosinostosis/fisiopatología , Craneosinostosis/cirugía , Procedimientos Neuroquirúrgicos/métodos , Distribución por Edad , Niño , Preescolar , Craneosinostosis/diagnóstico por imagen , Femenino , Humanos , Imagenología Tridimensional , Lactante , Presión Intracraneal/fisiología , Imagen por Resonancia Magnética , Masculino , Distribución por Sexo , Hueso Esfenoides/cirugía , Resultado del TratamientoRESUMEN
Objective:To investigate the value of 3D printing technology in sphenoid ridge meningioma dissection. Methods:By using craniocerebral spiral enhanced CT scan DICOM images, the skull, vessels, and tumor were extracted, reconstructed, and assembled and integrated in the same coordinate system. Then, we constructed a 3D virtual model and a 3D-printed entity model, which was ap-plied for preoperation and postoperation. Results:Virtual models of the brains of five patients were reconstructed successfully and 3D entity models were produced. The models expressed the relationship among tumors, adjacent blood vessels, and the important posi-tion of the nerve tissue. Then, the models were applied to the reference before surgery planning and after surgery. Five cases were successfully performed. Conclusion:The use of the entity model of sphenoid ridge meningioma is important in optimizing operation plans, improving tumor resection, and reducing intraoperative bleeding.
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Objective: To explore the application of extensive pterional approach combined with cutting of the zygomatic arch for the resection of large sphenoid ridge meningioma. Methods: Thirty-three patients with large sphenoid ridge meningioma underwent operation using the extensive pterional approach combined with cutting of the zygomatic arch. Twenty patients with large sphenoid ridge meningioma received operation with the traditional pterional approach as the control. The resection rate, operative time, intraoperative blood loss, and postoperative complications were compared between the groups. Results: Two groups of patients underwent craniotomy under microscope. The Simpon grade I resection and grade Ⅱ resection rate was 93.9％ in the cutting of the zygomatic arch approach group and 60.0％ in the control group (P<0.01). The operative time was (325.2±121.3) min in the cutting of the zygomatic arch approach group, which was significantly shorter than that in the control group with (406.4±182.9) min (P<0.05). The intraoperative blood loss was (502.5±101.8) mL and (697.7±115.4) mL in the two groups (P<0.05). In addition, postoperative complication rate was 15.2％ and 45.0％ in the cutting the zygomatic arch approach group and the control group, respectively (P<0.05). No death was reported in both groups. Conclusion: Extensive pterional approach combined with cutting of the zygomatic arch can fully expose the anatomical structures of the skull base and the sellar region to eliminate the influence of temporal muscle in the exposure of the surgical area. The operative field is exposed to reduce the stretch injury to only the frontotemporal brain tissue, which might be helpful for the complete resection of large sphenoid ridge meningioma, and is more conducive to neurovascular anatomy and relevant functional protection.
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The one-piece orbitozygomatic (OZ) approach is traditionally based on the McCarty keyhole. Here, we present the use of the sphenoid ridge keyhole and its possible advantages as a keyhole for the one-piece OZ approach. Using transillumination technique the osteology of the sphenoid ridge was examined on 20 anatomical dry skull specimens. The results were applied to one-piece OZ approaches performed on freshly frozen cadaver heads. We defined the center of the sphenoid ridge keyhole as a superficial projection on the lateral skull surface of the most anterior and thickest part of the sphenoid ridge. It was located 22 mm (standard deviation [SD], 0.22 mm) from the superior temporal line; 10.7 mm (SD, 0.08 mm) posterior and 7.1 mm (SD, 0.22 mm) inferior to the frontozygomatic suture. The sphenoid ridge burr hole provides exposure of frontal, temporal dura as well as periorbita, which is essential for the later bone cuts. There is direct access to removal of the thickest (sphenoidal) part of the orbital roof, after which the paper-thin (frontal) part of the orbital roof is easily fractured. The sphenoid ridge is an easily identifiable landmark on the lateral skull surface, located below the usual placement of the McCarty keyhole, with comparative exposure.
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Objective To explore the application of magnetic resonance angiography and virtual reality technique in preoperative planning for sphenoid ridge meningioma. Methods Ten patients with sphenoid ridge meningiomas were examined by brain CT, MRI and MRA before operation. Then the image data were transferred to the Dextroscope system. The images were reconstructed using the Radiodexter software to display the three dimensional image. The tumor and its adjacent anatomic structures could be viewed and the system tools allowed for simulation of the operation, so the full information of the tumor, basilar texture, and nerves and vessels could be obtained. A pre-operative planning was done and was compared with intra- operation situation. Results The virtual reality images of the 10 cases were successfully conducted, and all the procedures were performed according to the pre-operative planning, with a consistent rate of 100%. Radical resection was achieved and all the 10 patients and there were no sequelea. Conclusion Magnetic resonance angiography and the virtual reality system can provide the information of tumor and its adjacent structures, so it can Hp the neurosurgeons no planning the details for operation, contributing to operation safety and tumor resection.
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Objective To explore the microsurgical technique in managing medial sphenoid ridge meningioma.Methods The clinical data of 23 cases of medial sphenoidal ridge meningioma were analyzed retrospectively.The main points of microsurgical treatment of medial sphenoid ridge meningioma were discussed.Results Of 23 cases of medial sphenoid ridge meningiomas,total removal was made in 15 cases,subtotal removal in 6 cases and partial removal in 2 cases.The microsurgical outcomes were satisfactory in all the patients and no patients died.Conclusion The microsurgery via the pterional approach to the medial sphenoid ridge meningiomas can greatly heighten total resection rate of the tumors.Total resection of the tumor depends on its position,character and degree of edema of surrounding tissues.Palliative operations combined with postoperative radiotherapy should be carried out for treating the tumors that can only be subtotally and partially removed.