Skull base surgery

Surgical inaccessibility, the obstacles of vital neural and vascular anatomy, and the overwhelming surgical mortality rate as a result of hemorrhage and sepsis have led surgeons to approach lesions of the skull base with understandable reluctance. We have, however, undergone a technical revolution in microsurgery, anesthesia, and neurodiagnosis. Innovative surgical minds have thus been armed with the technology to make surgery a reasonable alternative for these dreaded lesions. This article singles out the glomus tumor and its associated lesions, which the neuro-otologist must approach transtemporally. Their diagnosis and new treatment concepts are discussed. Old criteria for unresectability are redefined and new classifications are established. Surgery of these skull base lesions is discussed from the standpoint of the basic principles of exposure, hemostasis, and management of the facial nerve. Problems in rehabilitation of postoperative deficits are discussed.     

颅底外科学进展

颅底外科学是20余年来逐渐发展起来的一门新兴交叉学科,是近年来最活跃的外科领域之一。近10余年来已有长足的发展。本文从颅底手术术式研究,内镜在颅底手术中的应用,影像学和立体定向技术对颅底外科学发展的影响等方面回顾10年来我国颅底外科学研究成果。     

Skull base surgery for malignancy: when not to operate

The purpose of this paper is to detail the contraindications for surgery, with curative intent for those patients who suffer from a head and neck malignancy that invades the intracranial space. This is based on a 30-year experience of over 250 patients. The most important contraindications are anatomical. Surgery is not done if the following structures are invaded: brain stem, eloquent portions of the cerebrum, superior sagittal sinus, both internal carotid arteries, both cavernous sinuses and certain vital bridging veins. Certain tumor factors are absolute but are occasionally relative contraindications: such as distant metastatic disease especially if multiple and at multiple anatomic sites. Some tumors that behave in a particularly virulent fashion that defy complete resection but are often difficult to predict preoperatively. Lack of patient medical fitness or absence of patient commitment to the operative procedure is make-up two serious contraindications to surgery. Presented at the 77th Annual Meeting of the German Society for Oto-Rhino-Laryngology, Head and Neck Surgery, 24–28 May 2006, Mannheim, Germany.     

颅底恶性肿瘤的颅面联合手术国际协作研讨组的报告

随着放射影像学的进展，手术技巧的提高，结合微血管重建术，采用经颅面联合径路（cranilfacial surgery，CFS）治疗临床上罕见的颅底良恶性肿瘤，渐成为首选方法。但此类患者不多，无一个中心可收治足够数量患者并采用CFS治疗，评价其疗效。为此，由17个医疗中心组成的国际协作组进行合作，回顾分析大宗病例，以期较客观地评价CFS的安全性和有效性，本文对分析结果进行总结。     

Histopathology of metastatic temporal bone tumors

Temporal bone metastasis is now being reported with increasing frequency. To understand the process of temporal bone metastasis, complete histologic evaluation of the temporal bones is essential. In this study, 60 temporal bones from 33 patients were evaluated. Different patterns of temporal bone involvement were noted depending on the mode of spread to the temporal bone. Involvement of the temporal bone usually occurs late in the disease process and is often asymptomatic.     

Skull base chordomas

Skull base chordomas are rare midline malignancies of clival origin that represent one of the most challenging skull base tumors to treat, given their location, invasiveness, potential extension around vital neurovascular structures, and high recurrence rate. Total tumor resection is the mainstay of treatment. The combination of surgery and postoperative irradiation appears to provide the best outcome.     

Skull base chordomas

Chordomas are rare, benign tumors of the nasopharynx. Because of their location at the skull base, removal of these tumors is usually subtotal. Described is the transcervical-transmandibular approach to the skull base which can be employed in removing these tumors.     

Skull base mapping

Early experience with medium to large tumors of the temporal region has re-emphasized the value of radiologic preoperative plotting of these space occupying lesions in the sagittal, coronal, and horizontal planes. Attention to probable pathology, neurovascular structures and patient's medical status has been important in determining resectability. A standard format of the interior and exterior of the skull base and cervical spine has been employed to map these lesions. Such devices have been used by otolaryngologists in the past to depict laryngeal lesions; and provide for the skull base surgeon a common base of comparison of tumor size, chart documentation, and a means to facilitate communication among other specialists. Experience with 36 cases of skull base tumors seen since July 1979 has emphasized the occult manner in which these lesions may present.     

Skull base reconstruction

Reconstruction of skull base defects following tumor resection is of paramount importance in avoiding serious and life-threatening complications. Cranial base surgery has evolved and outcomes have steadily improved as increasingly reliable reconstructive techniques have been adapted to repair the challenging wounds in this complex anatomic region. The most significant development has been the introduction and refinement of microvascular free tissue transfer to the skull base over the past 15 to 20 years. Free flaps can reliably provide the requisite tissue to not only seal the intracranial space from the subjacent cavities, but also to restore complex craniofacial defects that often result from skull base tumor excision. Advances in alloplast technology have also expanded the armamentarium available to the reconstructive surgeon. In particular, bone substitutes, titanium hardware, and resorbable plate fixation have been shown to be very efficacious when used in carefully selected situations. Finally, tissue sealants and adhesives have become widely used as an adjunctive method to achieve a water-tight dural repair.     

Long-term results of surgery for temporal bone paragangliomas

OBJECTIVES: Assessment of the long-term results of surgery for temporal bone paragangliomas with special consideration of the patient's ability to cope with the functional deficits. STUDY DESIGN: Retrospective review of 36 patients who had undergone resection of a temporal bone paraganglioma 10 to 15 years previously. Assessment of the patients' subjective view of the functional outcome and quality of life by a questionnaire. METHODS: Clinical records were reviewed regarding size of tumor, technique of surgery, supportive therapy, and tumor recurrence. Patients were sent a 50-item questionnaire evaluating their quality of life and the preoperative and postoperative function of cranial nerves VII through XII. RESULTS: A complete tumor removal was achieved in 30 patients (83%). There was only one tumor recurrence. The major negative effects of surgery involved hearing and dysphagia, which deterioriated in 14 and 12 patients, respectively. Thirty-five of the 36 patients (97%) reported that, despite deterioration, the cranial nerve deficits were still acceptable. Seventy-five percent of the patients regained their preoperative quality of life and 97% returned to their previous occupation in 1 to 2 years. CONCLUSIONS: The otologic extradural approach allowed complete tumor removal in 83%, with minimal perioperative morbidity. No surgically induced central nervous system lesions occured. Tracheostomy was avoided and all patients resumed oral feeding. Full rehabilitation after removal of class C and CD paragangliomas may take 1 to 2 years. However, the fact that 97% of the patients finally resumed normal social life showed the ability of most patients to cope with the sequelae of surgery even in class C and CD paragangliomas.     

Combined approach surgery for removal of glomus jugulare tumors

The ideal surgical treatment for glomus jugulare tumors is total removal. Efforts have been made periodically to accomplish this since shortly after this tumor was first identified in the early 1940's. This paper describes a method of removal using a combined approach through the neck and temporal bone, preceded by a course of preoperative irradiation therapy. The early results that have been obtained using this procedure in 10 patients are reported.