THE STEREOSCOPIC EFFECT OF A SPINNING BATON FLIGHT

INTRODUCTION: In baton twirling, catching a spinning baton is one of fundamental skills. For successful baton-catching, baton twirlers acquire the efficient visual search behavior setting their gaze not only to parabolic flight but spin of baton (Takahashi et al., 2007). Mazyn et al. (2007) reported that the learning to catch a ball is affected by stereo vision providing accurate depth perception of the ball’s movement. We consider a CAVE Automatic Virtual Environment system, 3D virtual reality display with stereoscopic effect, may be used as a training tool for baton-catching. This preliminary study aimed to examine the stereoscopic effect on the virtual reality simulation of baton-catching in a CAVE system. We reconstructed stereo- and monoscopic stimuli of spinning baton flight simulated by 3D motion capture data and assessed observer’s impression of them

放射線エネルギーの違いによる喉頭癌における吸収線量の影響

We investigated the usefulness of Gafchromic MD-55 film (Nuclear Associates, Inc.) for measuring the radiation doses on the radiotherapy of laryngeal cancers. Since larynx has thin wedge-shaped structure in anterior neck adjacent to airway, the radiation doses to the lesion may be diminished because of build-up and build-down. So, the dose has been measured with conventional measuring systems such as thermoluminescent dosimetry (TLD). However, it was not possible to evaluate the dose distribution correctly using TLD, because it is impossible to float a TLD chip in an air cavity. In this study, we employed Gafchromic MD-55 film as a dosimeter, for it can be set on the area of interest and with a measurability of dose range of 3 to 100 Gy, though it has no energy dependency. And this radiometer is composition near the soft tissue of the human body. The dose distributions to larynx were investigated with this film using neck phantom under each radiation beam energy of 4, 6 and 10 MV x-rays. Our neck phantom is made from acrylic resin and simulates a normal larynx on the basis of image information of computed tomography (CT). Moreover we observed secondary build-up and build-down curves in tissue in the vicinity of air cavities, especially at 10 MV x-rays. These findings suggest that patients with TI-T2 glottic cancers with anterior commissure invasion may receive more effective treatment with 4 MV x-rays rather than with 6 MV and 10 MV x-rays.Tl声門癌に対して放射線治療を単独で行うのは確立している方法である｡しかし,頚部は解剖学的に複雑であり,前方に薄いⅤ字形で,喉頭が気道に隣接している構造を持つので,病巣への線量はbuild-upとbuild-downの影響による線量低下が生じることが考えられる｡すなわち,放射線エネルギーの選択が喉頭癌の局所的制御に影響を及ぼすと言える｡この影響は,より高い放射線エネルギーでは,それに伴いより強く起きるということが基礎実験にて報告されている｡また,それらの線量測定は,熱ルミネセンス線量計(TLD)のような従来の測定システムで測定されていた｡しかし,空気空洞へTLD を単体 で浮かせ線量を正確に測定し評価を行うのは困難である｡本研究において,我々は Gafchromic MD-55 film (Nuclear Associates, Inc.)を使用し測定した｡ Gafchromic MD-55 film は,フィルムタイプ線量計でありエネルギー依存性がなく,3～100 Gyを測定可能であり,アクリル製頸部ファントムの空気組織境界面及び,空洞部に線量計を容易に精度良く配置することが可能である｡また,この線量計は人体の軟部組織に近い組成である｡そこで, 4, 6および10MVの各エネルギーでこの線量計を用いてエネルギーの違いによる,頸部ファントムを用いて喉頭の線量評価を行った｡その結果,我々は,特に放射線エネルギー10MVで頸部ファントムにおける,前部組織-組織空洞境界面-空洞部の一連したbuild-upおよびbuild-downを線量計で評価することができた｡これらの研究の結果､前交連浸潤を有するT1-T2に相当する声門癌患者は,放射線エネルギー6MVおよび10MVではなく,4MVを用いることによって,より効果的な放射線治療を行えると推測できる

Role of the limbus in femoral-head deformation in developmental dislocation of the hip: findings of two-directional hip arthrography.

Two-directional arthrographic findings made during conservative treatment of developmental dislocation of the hip were compared with the femoral-head configurations and radiological results obtained from long-term follow-up examinations in this retrospective study. Sixty hips were followed until at least age 14. Arthrography was carried out according to Terazawa's method. The shape of the superior, anterior, and posterior limbus was evaluated based on a modified Fujii's classification. The femoral-head configuration was classified into 4 groups, and the radiological results were evaluated using Severin's classification at the final observation. There was a statistically significant relationship between the shape of the anterior limbus, the number of portions of deformed limbus (superior, anterior, posterior), and the femoral-head configuration. Also, a statistically significant relationship between the shape of the limbus and Severin's classification was observed. These results suggest that the deformed limbus seems to play an important role in triggering femoral-head deformities, possibly via mechanical compression, and negatively affects development of the hip joint.</p

Reconstruction of Bone Defect Using the Bone Transport Technique for a Case of Osteosarcoma of the Femur

There are few reports on skeletal reconstruction using the bone transport technique to repair bone defects caused by resections of tumors associated with osteosarcoma. We attempted to reconstruct a 23 cm bone defect after resection of an osteosarcoma of the left femur, and succeeded in gaining 17 cm by bone transport. Five years after surgery, this patient remains alive without metastasis or local recurrence.</p

Association Between Aldosterone and Hypertension Among Patients With Overt and Subclinical Hypercortisolism

INTRODUCTION: Hypertension is one of the most common clinical features of patients with overt and subclinical hypercortisolism. Although previous studies have shown the coexistence of autonomous cortisol and aldosterone secretion, it is unclear whether aldosterone plays a role in hypertension among patients with hypercortisolism. Therefore, we examined the associations of plasma aldosterone concentrations (PACs) with hypertension among patients with overt and subclinical hypercortisolism. METHODS: This single-center retrospective cohort study included patients with adrenal tumor and serum cortisol levels after 1-mg dexamethasone suppression test >1.8 µg/dL (50 nmol/L). Using multivariable regression models adjusting for baseline characteristics, we investigated the association of PACs with systolic blood pressure and postoperative improvement of hypertension after the adrenalectomy. RESULTS: Among 89 patients enrolled in this study (median age, 51 years), 21 showed clinical signs of Cushing syndrome (overt hypercortisolism) and 68 did not show clinical presentations (subclinical hypercortisolism). We found that higher PACs were significantly associated with elevated systolic blood pressure among patients with subclinical hypercortisolism (adjusted difference [95% CI] = +0.59 [0.19-0.99], P = 0.008) but not among those with overt hypercortisolism. Among 33 patients with subclinical hypercortisolism and hypertension who underwent adrenalectomy, the postoperative improvement of hypertension was significantly associated with higher PACs at baseline (adjusted risk difference [95% CI] = +1.45% [0.35-2.55], P = 0.01). CONCLUSION: These findings indicate that aldosterone may contribute to hypertension among patients with subclinical hypercortisolism. Further multi-institutional and population-based studies are required to validate our findings and examine the clinical effectiveness of the intervention targeting aldosterone for such patients