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Purpose: To identify a casual pathway between the alteration in visual experience, due to form deprivation and hyperopic defocus, and the increase in eye growth, we searched for candidate genes having regulatory effects on eye growth under myopic conditions. Methods: The expression of the brain-derived neurotrophic factor, neurotrophin-3, sonic hedgehog, nerve growth factor, Six-3 and the Lh-2 group of genes in the transcriptional level after experimentally induced myopia (form-deprivation by goggles and by hyperopic defocus using negative spectacle lenses) were evaluated by semiquantitative reverse transcriptional polymerase chain reaction and Northern blot analysis. Results: Results showed that only the sonic hedgehog gene was differentially expressed in the experimentally induced myopic retinal samples compared with controls. Conclusions: The sonic hedgehog gene may have regulatory functions in the signaling of the cascade of events that leads to axial elongation and vitreous enlargement of the eye under myopic conditions.

PURPOSE: To evaluate the visual development in infants with stage 1 approximately 3 ROP and compare their visual results with healthy preterm infants. PATIENTS AND METHODS: One hundred forty-four premature infants were recruited and were divided into 3 groups according to the stage of ROP. Randomly selected preterm subjects with no ROP were taken as controls. Ophthalmic examinations started 4 to 7 weeks after birth and were repeated as needed until the retina was fully vascularized or until any ROP that developed had resolved. Grating acuity was measured by acuity cards between 35-45 weeks of corrected age and by PL method at 12, 18 and 24 months of age. RESULTS: Infants with stage 3 ROP had slightly lower visual acuity scores compared to other infants at most of the testing points throughout the 35-45 week period, which did not show statistical significance at any week. Infants with stage 2 and 3 ROP had similar visual acuity values but slightly lower acuity scores than infants with stage I or no ROP at the 12 month follow-up. The differences were not statistically significant. Stage 3 ROP infants had significantly lower acuity scores compared to infants with stage 1-2 or no ROP at the 18 and 24 month follow-up visits (p

手術時期4歳以下の両眼性先天白内障10例,片眼性先天白内障12例,片眼性外傷性白内障3例を対象に形態覚遮断弱視の治療の実際と問題点について検討した。両眼性先天白内障症例が術後視機能,弱視治療のコンプライアンスともに最も良好であった。一方片眼性先天白内障症例は極早期手術例を除いて手術時期と術後視力に相関があり,視力不良例が多く治療に苦慮する例が多かった。外傷性白内障症例は弱視治療は良好に行えており術後視機能はほぼ良好であった。本弱視では片眼性先天白内障症例が感受性期にうけた形態覚遮断が最も大きいものと考えられるが,治療としてはできるだけ原因疾患を迅速に取り除き,固定化を防ぐことが最も重要であるため,親に対する心理的なサポートを含めた生後早期からの注意深い観察と適切な対処をすることが必要であると考えた。

To clarify whether nitric oxide synthase (NOS) is involved in development of myopia, we examined the influence of form deprivation on the expressions of NOS isoform mRNA.NOS isoform cDNAs were amplified from total RNA extracted from control and 7-day-form-deprived chick retina-RPE (retinal pigment epithelium)-choroid, using competitive RT-PCR (reverse-transcription polymerase chain reaction). Each NOS isoform protein was also analyzed by Western blotting and immunohistochemistry.Expression of inducible NOS (iNOS) mRNA was highest in the control chick retina-RPE-choroid, followed by the expression of brain NOS (bNOS) mRNA. Expression of endothelial NOS (eNOS) mRNA was faint. The iNOS protein level, however, was only slightly higher than the levels of the bNOS and eNOS proteins and was found mainly in the outer part of the photoreceptor layer and inner and outer parts of RPE and choroid. bNOS alone was found in the outer nuclear layer. Although form deprivation reduced the iNOS and bNOS mRNA expressions, only the iNOS protein showed significant reduction.All three NOS isoforms were expressed in chick retina-RPE-choroid. Predominant expression of iNOS, instead of bNOS and eNOS, suggested the existence of ocular tissue-specific regulation of the iNOS gene. In addition to differences in expression level, bNOS displayed regional differential expression. Moreover, only iNOS was reduced in response to form deprivation. It is suggested that NOS isoforms may be differentially involved in the mechanisms regulating the posterior eye tissues, including myopic eye growth.

生後24週以内で先天白内障手術をうけた両眼性症例6例12眼,片眼性症例2例2眼の術後視力経過,立体視機能について検討した。手術時年齢は,両眼性は平均17.3±5.5週の両眼同時手術で片眼性では3週と20週であった。術後は速やかにハードコンタクトレンズの装用を行い,また左右差が確認された症例については多くとも覚醒時間の半分までの健眼遮蔽を指示した。術後視機能については,両眼性では全例0.6以上でうち4例7眼が1.0の視力を得ることができ立体視は4例に認められた。片眼性では1例が1.0の良好な視力が得られたが,健眼遮蔽のコンブライアンスが不十分な1例は,0.04の視力しか得られなかった。立体視は視力良好例にも獲得することができなかった。両眼性症例は視力,両眼視機能は概ね良好であったが,片眼性では両眼視機能獲得の難しさが確認された。

我々は屈折性および不同視性弱視症例のうち乱視を起因とする症例についてその治療経過を検討した。症例は乱視性屈折性弱視22例44眼,乱視性不同視弱視16例16眼につき最終視力,治療開始時より視力1.0を獲得するまでの期間およびTitmus Stereo Testsによる立体視について調べた。屈折性弱視では,86.4%の患児が視力1.0を獲得し,94.7%に100秒以下の立体視を得た。不同視弱視では93.8%の患児に視力1.0を得られ,100秒以下の立体視を得たのは93.3%であり,極めて良好な結果が得られた。乱視度数と治療開始時より視力1.0の獲得期間,乱視度数と立体視との間には2群とも相関関係はみられなかった。動物実験による経線弱視とは異なり,乱視を起因とする弱視症例の視力予後は極めて良好であることが確認できた。

The purpose of this study was to evaluate changes in the expression of different genes in chick retinal tissues after induction of experimental myopia and to evaluate the roles of these genes in the regulation of postnatal eye growth and myopia. Form-deprivation using occlusive goggles and hyperopic defocus by negative spectacle lenses were used to induce myopia in hatched chicks. Expression levels of Sonic hedgehog , its receptor complex, and other retinal cell genes were evaluated by semi-quantitative reverse transcription-polymerase chain reaction. Levels of Sonic hedgehog protein were further evaluated by Western blot analysis. The induction of myopia caused significant increase in expression of Sonic hedgehog mRNA and protein and increased expression of blue and red opsin mRNA. In contrast, the expression of mRNA for Sonic hedgehog receptor complex (Patched–Smoothened) , rhodopsin , vimentin , green opsin , violet opsin , and HPC-1 were unaffected by the induction of myopia. The increase in expression of Sonic hedgehog in chick retinas in experimentally-induced myopia suggests involvement in the retina control of postnatal eye growth. Furthermore, Sonic hedgehog may influence the expression of blue and red opsins under myopic conditions.

Form-deprivation of chicks during early postnatal development results in ocular enlargement and great myopic refractive error (form-deprivation myopia). Previous studies have indicated that the retina, RPE and choroid play important roles in ocular enlargement in form-deprivation myopia. We aimed to isolate genes up-regulated in the retina-RPE-choroid of form-deprived chick eyes. A suppression subtractive hybridization method was used to compare mRNA expression in the retina-RPE-choroid of form-deprived and control eyes. One up-regulated cDNA was isolated and identified as part of chick delta1-crystallin cDNA. Northern blot and RT-PCR analyses demonstrated that delta1-crystallin mRNA was up-regulated in the retina-RPE at day 7 after form-deprivation treatment. Semi-quantitative RT-PCE analysis of the expression of several transcription factors indicated that Sox1 and Sox3 were upregulated in parallel with delta1-crystallin mRNA in form-deprived eyes. Northern blot analysis demonstrated that alphaA-, betaA3/A1-, betaB1-, and betaB2-crystallin mRNAs were also up-regulated in form-deprived eyes. Although the detailed mechanisms and functions of the crystallin family genes in the retina-RPE-choroid of form-deprived eyes remain unclear, results of our study suggests that form-deprivation affects the expression of these genes in chick eyes.

To evaluate the results of congenital cataract extraction and postoperative visual function, we retrospectively reviewed the records of 95 patients who underwent pars plana (plicata) lensectomy or aspiration surgery. Forty-nine percent of the patients with bilateral aphakia and 25% with bilateral pseudophakia had a Landolt visual acuity of 0.5 or above at the final visit. The figures were 31% and 66% for patients with unilateral aphakia and pseudophakia, respectively. Eight patients (16.3%) with bilateral and 2 patients (5.8%) with unilateral cataract for whom contact lenses were prescribed after surgery attained fine stereopsis. Five of 8 patients (62.5%) with unilateral cataract who had intraocular lens implantation ended up with gross or fine stereopsis. We stress that very early surgery and optical correction in the sensitive period of binocular visual development should be instituted, especially in the presence of dense opacities. A good postoperative visual outcome can be achieved in patients undergoing late surgery if the opacities are light or partial in nature. We also reemphasize the importance of aggressive and diligent visual rehabilitation and occlusion therapy against amblyopia.

Conclusions: The IOL power calculation formulae show less accuracy in pediatric cases. It is also difficult to predict the changes in refraction for pediatric cases.