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AIM: To analyse the changing trends in penetrating keratoplasty (PKP) indications. METHODS: This retrospective study included all patients with PKP between 2006 and 2017. Patients were classified using histological diagnoses. Our groups were more than 10 various keratopathies. Additionally, two different time-periods (2006-2012 and 2013-2017) were analysed. Results: Totally 1721 histological analyses of 1214 patients were available for review. The diagnoses were pseudophakic or aphakic bullous keratopathy in 487 (28.3%), regraft in 443 (25.7%), acute necrotizing and ulcerative keratitis in 313 (18.2%), corneal scar in 153 (8.9%), keratoconus in 140 (8.1%). Fuchs’ dystrophy in 61 (3.5%), corneal dystrophy other than Fuchs’ in 46 (2.7%), other diagnoses in 44 (2.6%) and failed endothelial keratoplasty graft in 34 (2.0%) cases. From the first to the second analysed time-period, incidence of acute necrotizing and ulcerative keratitis, corneal scar, Fuchs’ dystrophy increased (P≤0.032 for all) and incidence of keratoconus significantly decreased (P=0.015). Conclusion: Pseudophakic or aphakic bullous keratopathy is the leading indication for PKP, followed by regraft and acute necrotizing and ulcerative keratitis.  相似文献   
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Purpose: To investigate the impact of donor and recipient factors on graft survival in penetrating keratoplasty (PK).

Material and Methods: This retrospective study included 365 eyes that underwent PK using corneas from 231 donors between June 2010 and June 2015. Patients were divided into three groups (group 1: primary endothelial diseases; group 2: iatrogenic endothelial disorders; and group 3: other pathologies with a healthy endothelium) according to PK indications. The primary outcome measure was corneal graft survival at the last visit (clear or opaque). Graft clarity was assessed using Kaplan–Meier survival analysis.

Results: The most frequent PK indication was keratoconus (KC) (20.5%) followed by pseudophakic bullous keratopathy (PBK) (18.9%). Donor age had a negative impact on endothelial cell density (ECD) measured by an eye bank specular microscope (p < 0.001). Median best-corrected visual acuity in logarithm of the minimum angle of resolution units increased from 2.1 to 0.8 at 1 year after PK (p < 0.001). The clear graft rate was 96.7% at year 1, 88.8% at year 2, and 85.5% at year 3. Overall graft survival was 84.9% during a median of 39 months (range: 24–79 months) of follow-up. A higher graft survival rate (67.2%) was observed in KC compared to PBK during 6 years (p < 0.001). Recipients younger than 50 years of age showed a better graft survival rate than those older than 70 years of age (p = 0.037). Donor ECD, time between excision and death, and preservation time had no significant effect on graft survival. Frequent graft rejection episodes (GREs) and additional procedures during surgery had a negative impact on graft survival (p < 0.001 and p = 0.014, respectively). A worse graft survival was observed in group 2 compared to groups 1 and 3 (p = 0.042).

Conclusions: Young recipient age and KC were associated with a better graft survival. Graft endothelial density and preservation time had no impact on graft survival. PBK, low vision at baseline and year 1, frequent GREs, and additional interventions during surgery had a negative impact on graft survivals.  相似文献   

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目的 分析先天性角膜混浊(congenital corneal opacities,CCO)患儿的临床特征,为其诊断及治疗提供依据。方法 回顾性分析2017年1月1日至12月31日在我院接受手术治疗的CCO患儿的临床资料,包括CCO患儿一般特征及临床分类、患病单双侧、相关的眼部和全身异常、病理改变和接受的治疗等资料。结果 本研究纳入66例(93眼)CCO患儿,其中年龄3~36(13.11±9.63)个月,39例(59.1%)为单眼患病,最常见的临床类型是Peters异常(32例,48.5%)和角膜巩膜化(15例,22.7%);虹膜粘连(61眼,65.6%)和白内障(22眼,23.7%)是两种最常见的眼部异常;5例(7.6%)患儿出现全身异常,包括生长迟缓(4例)和先天性脑缺陷(1例)。93眼中85眼(91.4%)进行了穿透性角膜移植术,6眼(6.5%)进行了板层角膜移植术。结论 年龄≤3岁的CCO患儿中最常见的临床类型为Peters异常及角膜巩膜化;除角膜混浊外,CCO患儿还可能存在虹膜粘连、白内障等眼部异常或生长迟缓等全身异常;穿透性角膜移植术为治疗CCO的主要手术方法。  相似文献   
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The cross-sectional area of a blood vessel determines its resistance, and thus is a regulator of local blood flow. However, the cross-sections of penetrating vessels in the cortex can be non-circular, and dilation and constriction can change the shape of the vessels. We show that observed vessel shape changes can introduce large errors in flux calculations when using a single diameter measurement. Because of these shape changes, typical diameter measurement approaches, such as the full-width at half-maximum (FWHM) that depend on a single diameter axis will generate erroneous results, especially when calculating flux. Here, we present an automated method—thresholding in Radon space (TiRS)—for determining the cross-sectional area of a convex object, such as a penetrating vessel observed with two-photon laser scanning microscopy (2PLSM). The thresholded image is transformed back to image space and contiguous pixels are segmented. The TiRS method is analogous to taking the FWHM across multiple axes and is more robust to noise and shape changes than FWHM and thresholding methods. We demonstrate the superior precision of the TiRS method with in vivo 2PLSM measurements of vessel diameter.  相似文献   
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Missile embolization to the heart occurs infrequently in penetrating trauma. The lack of a concentrated experience at any single institution contributes to the controversies pertaining to diagnostic and therapeutic approaches to management. The objective of this study was to describe a case of a left ventricular bullet embolus and provide a detailed diagnostic and therapeutic framework for management of intracardiac projectiles. Initial management of a patient with suspected intracardiac projectiles is dictated by his or her hemodynamic status. Unstable patients generally require operative intervention. In the stable patient, associated injuries must be sought. Localization of the projectile can be aided by echocardiogram, fluoroscopy, or angiography. Definitive management is individualized, and can range from observation to percutaneous or operative extraction. The decision depends on the cardiac chamber involved, the patients' symptoms, and the projectile's size, shape, and location within the chamber. Missile embolus to the heart is an infrequent occurrence, but when found presents a diagnostic and therapeutic challenge. Management strategies should be individualized. A detailed management algorithm is provided.  相似文献   
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