Hitting a moving target: evolution of a treatment paradigm for atypical meningiomas amid changing diagnostic criteria.

OBJECT: The World Health Organization (WHO) reclassified atypical meningiomas in 2000, creating a more clear and broadly accepted definition. In this paper, the authors evaluated the pathological and clinical transition period for atypical meningiomas according to the implementation of the new WHO grading system at their institution. METHODS: A total of 471 meningiomas occurring in 440 patients between 1994 and 2006 were retrospectively reviewed to determine changes in diagnostic rates, postoperative treatment trends, and early outcomes. RESULTS: Between 1994 and 2000, the incidence of the atypical meningiomas ranged from 0 to 3/year, or 4.4% of the meningiomas detected during the entire period. After 2002, the annual percentage of atypical meningiomas rose over a 2-year period, leveling off at between 32.7 and 35.5% between 2004 and 2006. The authors also found a recent trend toward increased use of adjuvant radiation therapy for incompletely resected atypical meningiomas. Prior to 2003, 18.7% were treated with this therapy; after 2003, 34.4% of lesions received this treatment. Incompletely resected tumors were treated with some form of radiation 76% of the time. In cases of complete resection, most patients were not given adjuvant therapy but were expectantly managed by close monitoring using serial imaging and by receiving immediate treatment for tumor recurrence. The overall recurrence rate for expectantly managed tumors was 9% over 28.2 months, and 75% of recurrences responded to delayed radiation therapy. CONCLUSIONS: The authors documented a significant change in the proportion of meningiomas designated as atypical during a transition period from 2002 to 2004, and propose a conservative strategy for the use of radiation therapy in atypical meningiomas.

Use of the clavicle in anterior cervical discectomy/corpectomy fusion procedures: cadaveric feasibility study.

INTRODUCTION: Graft sources for cervical fusion procedures include synthetic materials, donor grafts, and autologous bones such as the iliac crest. Considering the data that autologous bone grafts seem to generate the best results for fusion, the next logical step is to seek alternative donor sites so as to attempt to reduce the morbidity associated with these procedures. To our knowledge, autologous clavicle has not been explored as a potential source for cervical fusion. Therefore, the following study was performed to verify the utility of this bone for these procedures. MATERIALS AND METHODS: Seven adult cadavers were used for this study. In the supine position, a standard surgical approach and dissection to the anterior cervical spine were performed. Specimens underwent a standard discectomy or corpectomy with placement of harvested ipsilateral clavicle previously dissected. An anterior cervical plating system was next placed over these sites using standard techniques. Measurements of the harvested clavicle were made. RESULTS: The results of our morphometric analysis were as follows: An average of 5 cm of bone was easily removed from the middle one third of the clavicle. No gross injury was found to vicinal neurovascular structures. The middle one third of the clavicle offered sufficient bone for the one to two segments fused in our study with remaining bone for at least two additional segments. The mean diameter of this part of the clavicle was 1.2 cm. CONCLUSIONS: Based on our cadaveric study, such a bony substitute as autologous clavicle might be a reasonable alternative to the iliac crest for use in anterior cervical fusion procedures.