The aim of this study was to investigate the factors affecting cough ability, and to compare the assisted cough methods in patients with Duchenne muscular dystrophy (DMD). A total seventy-one male patients with DMD were included in the study. The vital capacity (VC) and maximum insufflation capacity (MIC) were measured. The unassisted peak cough flow (UPCF) and three different techniques of assisted peak cough flow were evaluated. UPCF measurements were possible for all 71 subjects. But when performing the three different assisted cough techniques, peak cough flows (PCFs) could be obtained from only 51 subjects. The mean value of MICs (1801 ± 780 cc) was higher than that of VCs (1502 ± 765 cc) (p < 0.01). All three assisted cough methods showed a significantly higher value than the unassisted method (F=80.92, p < 0.01). The manual assisted PCF under MIC (MPCFmic) significantly exceeded those produced by manual assisted PCF (MPCF) or PCF under MIC (PCFmic). The positive correlation between the MIC, VC difference (MIC-VC), and the difference between PCFmic and UPCF (PCFmic-UPCF) was seen (r=0.572, p < 0.01). The preservation of pulmonary compliance is important for the development of an effective cough as well as assisting the compression and expulsive phases. Thus, the clinical importance of the inspiratory phase and pulmonary compliance in assisting a cough should be emphasized.

small case series for the management of brainstem metastases using Gamma Knife Radiosurgery (GKRS) 12,16,18,22,26,35) . The present study assessed outcomes following our use of GKRS for the management of brainstem metastasis, and we investigated the effect of treatment on tumor size and survival time. MATERIALS AND METHODS Patient characteristicsFrom November 1992 to June 2010, a total of 32 patients underwent GKRS for local control of brainstem metastasis at our institute. The clinical characteristics of the 32 patients are summarized in Table 1. The study population consisted of 23 men and 9 women, with a mean age of 56.1 years (range, 39-73). The primary malignancy was lung cancer in 21 patients, breast cancer in 3, renal cell cancer in 2, prostate cancer in 2, and hepatocellular carcinoma, colorectal cancer in 1, gastric cancer in 1, and melanoma in 1. Fourteen patients had score of more than 70 on the Karnofsky performance status (KPS), and 18 had scores of less than 70. Lesions were located in the pons in 23 patients, the midbrain in 6 and the medulla oblongata in 3 patients. Fifteen patients presented with brainstem signs which INTRODUCTIONMetastasis to the brain is a frequent complication of malignant tumors of the lung, breast, kidney, and of malignant melanoma 2) . Metastatic brain lesions are estimated to eventually develop in 15 to 40% of patients with cancer 31) , and autopsy studies show brain metastases in 24% of cancer patients. However, brainstem metastases are uncommon, and account for only 3 to 5% of all brain metastases 8,17,30) . Brainstem metastases are generally not treated surgically due to the risk of causing neurological damage. Whole brain radiation therapy (WBRT) and stereotactic radiosurgery have been reported to provide benefits in brain metastases patients 3,4,9,10,14,19,29) . However, the benefits of such treatment in brainstem metastasis patients remain unclear.Since the first report of Huang et al. series 15) , there were some Department of Neurosurgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, KoreaObjective : Brainstem metastases are rarely operable and generally unresponsive to conventional radiation therapy or chemotherapy. Recently, Gamma Knife Radiosurgery (GKRS) was used as feasible treatment option for brainstem metastasis. The present study evaluated our experience of brainstem metastasis which was treated with GKRS. Methods : Between November 1992 and June 2010, 32 patients (23 men and 9 women, mean age 56.1 years, range 39-73) were treated with GKRS for brainstem metastases. There were metastatic lesions in pons in 23, the midbrain in 6, and the medulla oblongata in 3 patients, respectively. The primary tumor site was lung in 21, breast in 3, kidney in 2 and other locations in 6 patients. The mean tumor volume was 1,517 mm 3 (range, 9-6,000), and the mean marginal dose was 15.9 Gy (range, 6-23). Magnetic Resonance Imaging (MRI) was obtained every 2-3 months following GKRS. Follow-up MRI was possible in 24 patients at a mean follow-up durat...