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  • Author or Editor: Robert W.J. Ryan x
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Robert J. Spinner, Bernd W. Scheithauer, Arie Perry, Kimberly K. Amrami, Ryan Emnett and David H. Gutmann

✓ The authors report on a patient without neurofibromatosis Type 1 or 2 (NF1 or NF2) and without evidence of schwannomatosis, who was found to have an unusual combination of nerve sheath tumors—a large cellular schwannoma and multifascicular involvement of a plexiform neurofibroma arising from the same site within the radial nerve and posterior cord of the infraclavicular brachial plexus. This case broadens the spectrum of combined pathological features of nerve sheath tumors. Genetic studies revealed a combined loss of neurofibromin and merlin in both regions and chromosome arm 22q deletion within the neurofibroma component only. The latter finding supports the suggestion that these were two different clonal neoplasms, and is consistent with a collision tumor pattern.

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James C. Dickerson, Katherine L. Harriel, Robert J. Dambrino IV, Lorne I. Taylor, Jordan A. Rimes, Ryan W. Chapman, Andrew S. Desrosiers, Jason E. Tullis and Chad W. Washington


Deep vein thrombosis (DVT) is a major focus of patient safety indicators and a common cause of morbidity and mortality. Many practices have employed lower-extremity screening ultrasonography in addition to chemoprophylaxis and the use of sequential compression devices in an effort to reduce poor outcomes. However, the role of screening in directly decreasing pulmonary emboli (PEs) and mortality is unclear. At the University of Mississippi Medical Center, a policy change provided the opportunity to compare independent groups: patients treated under a prior paradigm of weekly screening ultrasonography versus a post–policy change group in which weekly surveillance was no longer performed.


A total of 2532 consecutive cases were reviewed, with a 4-month washout period around the time of the policy change. Criteria for inclusion were admission to the neurosurgical service or consultation for ≥ 72 hours and hospitalization for ≥ 72 hours. Patients with a known diagnosis of DVT on admission or previous inferior vena cava (IVC) filter placement were excluded. The primary outcome examined was the rate of PE diagnosis, with secondary outcomes of all-cause mortality at discharge, DVT diagnosis rate, and IVC filter placement rate. A p value < 0.05 was considered significant.


A total of 485 patients met the criteria for the pre–policy change group and 504 for the post–policy change group. Data are presented as screening (pre–policy change) versus no screening (post–policy change). There was no difference in the PE rate (2% in both groups, p = 0.72) or all-cause mortality at discharge (7% vs 6%, p = 0.49). There were significant differences in the lower-extremity DVT rate (10% vs 3%, p < 0.01) or IVC filter rate (6% vs 2%, p < 0.01).


Based on these data, screening Doppler ultrasound examinations, in conjunction with standard-of-practice techniques to prevent thromboembolism, do not appear to confer a benefit to patients. While the screening group had significantly higher rates of DVT diagnosis and IVC filter placement, the screening, additional diagnoses, and subsequent interventions did not appear to improve patient outcomes. Ultimately, this makes DVT screening difficult to justify.

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Roger J. Packer, Leslie N. Sutton, Joel W. Goldwein, Giorgio Perilongo, Greta Bunin, Janis Ryan, Bruce H. Cohen, Gulio D'Angio, Eric D. Kramer, Robert A. Zimmerman, Lucy B. Rorke, Audrey E. Evans and Luis Schut

✓ Between 1975 and 1989, 108 children with newly diagnosed medulloblastoma/primitive neuroectodermal tumor (MB/PNET) of the posterior fossa were treated at the authors' institution. The patients were managed uniformly, and treatment included aggressive surgical resections, postoperative staging evaluations for extent of disease, and craniospinal radiation therapy with a local boost.

Beginning in 1983, children with MB/PNET were prospectively assigned to risk groups; those with “standard-risk” MB/PNET were treated with radiation therapy alone, while those in the “poor-risk” group received similar radiation therapy plus adjuvant chemotherapy with 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU), vineristine, and cisplatin. The 5-year actuarial disease-free survival rate for all patients treated between 1975 and 1982 was 68%, and 73% when patients who died within 2 weeks after operation were excluded. This survival rate was statistically better for patients treated after 1982 (82%) compared to those treated between 1975 and 1982 (49%) (p < 0.004). There was no difference in disease-free survival rates over time for children with standard-risk factors; however, there was a significant difference in the 5-year survival rate for poor-risk patients treated prior to 1982 (35%) compared to those treated later (87%) (p < 0.001). For the group as a whole, a younger age at diagnosis correlated with a poorer survival rate; however, this relationship between age and outcome was significant only for children treated before 1983 (p < 0.001). These results demonstrated an encouraging survival rate for children with MB/PNET, especially those treated with aggressive surgical resection followed by both radiation therapy and chemotherapy. The results strongly suggest that chemotherapy has a role for some, and possibly all, children with MB/PNET.

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Oral Presentations

2010 AANS Annual Meeting Philadelphia, Pennsylvania May 1–5, 2010