1/10. Microvascular reconstruction of the skull base: indications and procedures.PURPOSE: The aim of the current study was to review the use of free tissue transfer for reconstruction of the skull base and for coverage of intracranial contents. patients AND methods: From 1990 until 1996, revascularized flaps were transferred to the skull and the skull base in 11 patients in whom intracranial/extracranial resection of tumors of the skull base was performed in cooperation with the Department of neurosurgery. The defects resulted from removal of squamous cell carcinomas (n = 4), basal cell carcinomas (n = 4), malignant melanoma, malignant schwannoma, and malignant meningioma. Defect repair was accomplished by revascularized transfer of latissimus dorsi muscle flaps in seven cases and rectus abdominis flaps and forearm flaps in two cases each. In five patients with extensive intracranial tumor spread, reconstruction was performed for palliative reasons. RESULTS: A safe soft tissue closure of the intracranial and intradural space was achieved in all patients, whereas the contour of the facial skull and the neurocranium was satisfactorily restored at the same time. By using the entire length of the grafted muscle, the vascular pedicle could be positioned next to the external carotid artery and conveniently connected to the cervical vessels. The mean survival time of the patients with palliative treatment was 8.4 months, with an average duration of hospital stay of 24.5 days. CONCLUSIONS: Despite the increased surgical effort of revascularized tissue transfer, microvascular reconstruction of large skull base defects appears to be justified, even as a palliative measure.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
2/10. Cystic hygroma of the skull base.Cystic hygroma is a benign developmental tumor formed by lymph vessels that occurs in 1 of 12000 individuals and presents most frequently in the head and neck. It is often difficult to manage because the tumor frequently envelopes nearby vital structures. Lesions that extend significantly above the hyoid are especially difficult to excise because of the complexity of achieving a complete excision. This article describes a series of 3 cases of cystic hygroma that presented in the head and neck and, on further investigation, were found to also involve the skull base. This anatomic location is exceedingly rare, and these 3 cases represent new and difficult challenges not previously discussed in the literature, to our knowledge.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
3/10. Interstitial brachytherapy for skull base tumors.1. Irrespective of the histology, all tumors responded to 125I permanent BT. 2. There were no intra- or postprocedural complications, making this modality extremely safe. 3. There were no acute or late complications attributable to continuous LDR radiation with 125I permanent BT. 4. The dose distribution can be tailored to fit the tumor shape by seed placement at the desired location and by selecting the seed strength. 5. Unlike any other radiation therapy procedure, with SBT, the placement of the 125I seed or seeds is verifiable at each step of the procedure on the CT screen, making the treatment more accurate. 6. The procedure is performed under local anesthesia, and the patient is observed overnight at the most, making it safe and cost-effective. 7. Most skull base tumors are located close to the brain, cranial nerves, or blood vessels. Tolerance of these vital structures to high doses of radiation when given continuously at a LDR makes this treatment method safe.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
4/10. Complex tumors of the glomus jugulare: criteria, treatment, and outcome.OBJECT: Tumors of the glomus jugulare are benign, slow-growing paragangliomas. Their natural history, surgical treatment, and outcome have been well addressed in the recent literature; however, there remains a subgroup of complex tumors--multiple, giant, malignant, neuropeptide-secreting lesions, and those treated previously by an intervention with an adverse outcome--that is high risk, presents surgical challenges, and is associated with treatment controversy. In this article the authors report on a series of patients with complex glomus jugulare tumors and focus on treatment decisions, avoidance of complications, surgical refinements, and patient outcomes. methods: In this retrospective study, the patient population was composed of 11 male and 32 female patients (mean age 47 years) with complex tumors of the glomus jugulare who were treated by the senior author within the past 20 years. These include 38 patients with giant tumors, 11 with multiple paragangliomas (seven bilateral and four ipsilateral), two with tumors that hypersecreted catecholamine, and one with a malignant tumor. Six patients had associated lesions: one dural arteriovenous malformation, one carotid artery (CA) aneurysm, two adrenal tumors, and two other cranial tumors. All but one patient presented with neurological deficits. Cranial nerve deficits, particularly those associated with the lower cranial nerves, were the prominent feature. Twenty-eight patients underwent resection in an attempt at total removal, and gross-total resection was achieved in 24 patients. Particularly challenging were cases in which the patient had undergone prior embolization or CA occlusion, after which new feeding vessels from the internal CA and vertebrobasilar artery circulation developed. The surgical technique was tailored to each patient and each tumor. It was modified to preserve facial nerve function, particularly in patients with bilateral tumors. Intrabulbar dissection was performed to increase the likelihood that the lower cranial nerves would be preserved. Each tumor was isolated to improve its resectability and prevent blood loss. No operative mortality occurred. In one patient hemiplegia developed postoperatively due to CA thrombosis, but the patient recovered after an endovascular injection of urokinase. In four patients a cerebrospinal fluid leak was treated through spinal drainage, and in five patients infection developed in the external ear canal. Two of these infections progressed to osteomyelitis of the temporal bone. There were two recurrences, one in a patient with a malignant tumor who eventually died of the disease. CONCLUSIONS: Despite the challenges encountered in treating complex glomus jugulare tumors, resection is indicated and successful. Multiple tumors mandate a treatment plan that addresses the risk of bilateral cranial nerve deficits. The intrabulbar dissection technique can be used with any tumor, as long as the tumor itself has not penetrated the wall of the jugular bulb or infiltrated the cranial nerves. Tumors that hypersecrete catecholamine require perioperative management and malignant tumors carry a poor prognosis.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
5/10. Use of "bonnet" bypass with radial artery interposition graft in a patient with recurrent cranial base carcinoma: technical report of two cases and review of the literature.OBJECTIVE AND IMPORTANCE: Two patients with recurrent cranial base carcinomas involving the carotid artery received a "bonnet" bypass using the contralateral superficial temporal artery as the donor vessel because the ipsilateral common and external carotid arteries were unavailable. The radial artery was used as the graft. CLINICAL PRESENTATION: A 58-year-old man with ear pain and an enlarging mass involving the left cranial base and neck had undergone a right partial glossectomy and modified neck dissection followed by radiotherapy for squamous cell carcinoma. Recurrent carcinoma extensively involved the left internal carotid artery. A 46-year-old man with jaw pain and hoarseness had undergone multiple resections and radiation therapy for medullary thyroid carcinoma. magnetic resonance imaging showed recurrent tumor on the right. INTERVENTION: Both patients underwent a pterional craniotomy. The supraclinoid internal carotid artery was exposed. The radial artery was harvested. The contralateral superficial temporal artery was dissected at its bifurcation into the frontal and parietal branches. The radial artery graft was anastomosed to the superficial temporal artery and a recipient ipsilateral branch of the middle cerebral artery. The internal carotid artery was clip-ligated. After surgery, both patients remained neurologically stable. Angiography confirmed that the bypasses were patent and that the middle cerebral artery territory filled. The patients' carcinomas were resected aggressively. CONCLUSION: When aggressive resection of cranial base tumors is needed and the ipsilateral carotid artery is unavailable as a donor vessel, a "bonnet" bypass with carotid artery sacrifice may be performed. Compared with vein grafts, microsurgical anastomosis is easier and the patency rate is higher with a radial artery graft.- - - - - - - - - - ranking = 2keywords = vessel (Clic here for more details about this article) |
6/10. hemangiopericytoma of the infratemporal fossa: progression toward malignancy in a 30-year history.hemangiopericytoma is a rare vascular tumor first described by Stout and Murray in 1942 and characterized by a proliferation of Zimmermann's pericytes, smooth muscle cells arranged around blood vessels. This tumor presents as a slowly enlarging painless mass. diagnosis with certainty is often a difficult one because of the close likeness with other spindle cell tumors; it requires the help of immunohistochemical techniques and sometimes ultrastructural techniques. Only 15% of hemangiopericytomas are localized in the cervicofacial region; in particular, occurrence in the infratemporal fossa is an exceptional occurrence. In this article, we report an unusual case of recidivate hemangiopericytoma of the infratemporal fossa that has progressively assumed features of malignancy over 30 years. The hemangiopericytoma relapse potentiality is elevated, even when the histologic characteristics of the tumor indicate a low aggressivity, and therefore every hemangiopericytoma must be considered to have malignant potential. In conclusion, the unpredictable behavior of hemangiopericytoma requires a radical primary treatment to avoid the risk of relapses that always are frequent and aggressive.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
7/10. Management of cranial base chondrosarcomas.OBJECTIVE: Chondrosarcomas are rare, infiltrative, progressive lesions that occur at the cranial base. Their intimate association with cranial nerves and major vessels of the head and neck often precludes complete surgical resection. methods: Between 1983 and 2003, 23 patients (14 females, 9 males) were treated at our institution with the diagnosis of chondrosarcoma of the cranial base (mean age at presentation, 43 yr). A retrospective chart review was performed to evaluate presentation, management, and adjunctive treatment. All living patients were contacted for a current examination and disease status. RESULTS: The 23 patients underwent 43 surgical resections. Follow-up ranged from 8 months to 25 years (mean, 97 mo). Ten patients underwent various adjuvant radiation therapies. Five patients have died. Four patients have no evidence of disease, and 13 have residual tumor. One was lost to follow-up. Of 14 patients with 5 years of follow-up, 13 are living. Therefore, the absolute 5 year survival rate is 93%. The 10 year survival rate is 71%. CONCLUSION: Because of the intricate nature of the cranial base, a team approach is preferable for managing these challenging lesions. Maximum cytoreductive surgery should be pursued as an initial strategy to minimize neurological injury. Adjuvant stereotactic radiosurgery can be used to treat residual disease or small recurrences. This cohort also illustrates that patients with chondrosarcomas have better long-term survival rates than patients with chordomas of the cranial base.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
8/10. A combined reverse temporalis muscle flap and pericranial flap for reconstruction of an anterior cranial base defect: a case report.After the excision of a recurrent squamous cell carcinoma in a 52-year-old man, a reverse temporalis muscle flap combined with a pericranial flap was used to reconstruct the anterior cranial base and the frontal defect. The combined flap is based on the superficial temporal fascia supplied by the superficial temporal vessels. We recommend the usage of the combined reverse temporalis muscle flap and the pericranial flap for reconstruction of the anterior cranial base, the frontal region, and other facial defects.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
9/10. Treatment of posterior skull base tumors.Surgery for posterior skull base tumors may be associated with high morbidity and mortality because of the complex anatomy, irregular bony topography, and vital neurovascular structures in this region. We experienced three benign posterior skull base tumors. These were petroclival and foramen magnum meningiomas and a jugular formen neurinoma. Three dimensional computed tomography (3 D-CT) in addition to the conventional CT, magnetic resonance imaging (MRI), and cerebral angiography were performed preoperatively. Preoperative embolizations for the tumors were also done, and intraoperative neurophysiological monitorings were performed. The tumors could be subtotally removed with no damage to the brainstem, cranial nerves, and vessels. No newly developed postoperative neurological symptoms were observed. As to the remaining tumors, gamma knife (gamma-knife) therapy was planned. 3 D-CT was very useful in the preoperative evaluation of the surgical approach, and the intraoperative neurophysiological monitoring was considered to be necessary to prevent permanent damage. gamma-knife after direct approach was recommended for the benign posterior skull base tumors.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
10/10. Model-based surgical planning and simulation of cranial base surgery.Plastic skull models of seven individual patients were fabricated by stereolithography from three-dimensional data based on computed tomography bone images. Skull models were utilized for neurosurgical planning and simulation in the seven patients with cranial base lesions that were difficult to remove. Surgical approaches and areas of craniotomy were evaluated using the fabricated skull models. In preoperative simulations, hand-made models of the tumors, major vessels and nerves were placed in the skull models. Step-by-step simulation of surgical procedures was performed using actual surgical tools. The advantages of using skull models to plan and simulate cranial base surgery include a better understanding of anatomic relationships, preoperative evaluation of the proposed procedure, increased understanding by the patient and family, and improved educational experiences for residents and other medical staff. The disadvantages of using skull models include the time and cost of making the models. The skull models provide a more realistic tool that is easier to handle than computer-graphic images. Surgical simulation using models facilitates difficult cranial base surgery and may help reduce surgical complications.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
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