IOLmodeling and light imulation for glare source analysis

眼病として眼球の水晶体が白く濁る白内障がある.この病気により一度白く濁った水晶体は元に戻ることは無い.水晶体中の白く濁った部分を除去し,その中に眼内レンズを挿入する小切開白内障手術を行うことにより,視力の回復が見込まれる.しかし,術後の後遺症の一つとしてグレアの知覚が挙げられる.グレアとはレンズを挿入したことにより生じるぎらつきのことを指す.グレアの発生原因に関する詳しい解析はまだ十分に行われていない.本稿では,グレア発生原因解析の基礎研究として,眼内レンズ断面形状のモデル化.眼内レンズに入射する光を反射・屈折を考慮して光線追跡を行い,眼底での輝度分布をシミュレーションする方法について述べる.Cataract is the eye disease which clouds the lens of the eye. Vision can be returned through the cataract operation which inserts an intraocular lens into the eye. However a postoperative after effect exists in which a glare is generated. In this paper we approximate IOL's cross section shape using least squares approach, and trace light rays via taking into accout reflection and refraction. Then by observing the distribution of Rays onto a Fundus model we determined a glare exists

IOLmodeling and light imulation for glare source analysis

MIRU2007 第10回 画像の認識・理解シンポジウム ポスター資料 ; 開催日時:2007年7月30日～8月1

A method for accurate reconstruction of fundus volume data from radially cross-sectional images

医学の分野において,眼病の早期発見および経過観察のために,眼底の3次元形状の詳細な観察が望まれている.本論文では,Optical Coherence Tomography (OCT)を用いて,放射状にスキャンされた複数枚の断面画像から,眼底ボリュームデータを高精度に構築する手法を提案する.すなわち,眼球の動きによる回転誤差を考慮して,スキャン時に生じるスキャン位置のずれを合わせる手法を開発した.この手法を用いて構築した眼底ボリュームデータに可視化処理を施すことにより,眼底表面形状とともに,眼底内部構造も観察が可能となり,医師の診断支援になることが期待される.In medicine, detail observation of a three-dimensional fundus shape is necessary for diagnosing eye-disease accurately and checking the treatment process. In the paper, we propose a method for accurate reconstruction fundus volume data from cross-sectional images scanned radially with an optical coherence tomography (OCT). We developed the method for correct deviation from positions of cross-sectional images taking into account errors caused by eye movement. Visualizing the fundus volume data generated by the proposed method, the fundus shape and the internal structures can be easily observed. The method is a promising technique for diagnosis of eye-disease

A method for accurate reconstruction of fundus volume data from radially cross-sectional images

MIRU 2007 第10回 画像の認識・理解シンポジウム ポスター資料 ; 開催場所 : 広島市立大学, 広島 ; 開催日時:2007年7月30日～8月1

Authentic role of ATP signaling in micturition reflex

Adenosine triphosphate (ATP) is a signaling molecule that regulates cellular processes. Based on previous studies of bladder function over the past decade, bladder ATP signaling was thought to have an essential role in the normal micturition reflex. In this study, we performed detailed analyses of bladder function in purinergic receptor-deficient mice using the automated voided stain on paper method and video-urodynamics. Unexpectedly, a lack of P2X2 or P2X3 receptors did not affect bladder function under normal physiological conditions, indicating that bladder ATP signaling is not essential for normal micturition reflex. In contrast, we found that lipopolysaccharide (LPS) induced markedly high levels of ATP release from the urothelium. In addition, LPS-induced rapid bladder hyperactivity was attenuated in P2X2 -/- and P2X3 -/- mice. Contrary to the previous interpretation, our present findings indicate that bladder ATP signaling has a fundamental role in the micturition reflex, especially in bladder dysfunction, under pathological conditions. Therefore, the bladder ATP signaling pathway might be a highly promising therapeutic target for functional bladder disorders. This study newly defines an authentic role for bladder ATP signaling in the micturition reflex