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101.
儿童白内障术后远期结果的研究进展 总被引:1,自引:1,他引:0
本文对近几年一些学者对儿童白内障远期随访结果进行了综述和评价。手术时机选择、儿童特殊的屈光变化以及如何精确测定儿童植入人工晶状体性能及屈光度都对儿童白内障术后远期视功能产生影响。慢性青光眼是儿童白内障术后远期丧失视力的主要原因。长期弱视治疗是获得手术成功的保证之一。因此,要真正获得有用的视功能,应重视儿童白内障手术后的后续治疗,并提议应建立完善的白内障术后追踪随访和弱视治疗机构。 相似文献
102.
目的 研究虹膜夹型有晶状体眼人工晶状体(iris-claw phakic intraocular lens,ICPIOL)植人术后对比敏感度(contrastsensitivity,CS)的变化。方法 2005年5月至12月于温州医学院附属眼视光医院和中山大学中山眼科中心接受ICPIOL(Verisyse,美国AMO公司)植入术的高度近视眼患者12例(23只眼),分别在术前、术后1、3、6个月采用CS测试灯箱(CSV-1000型,美国Vector Vision公司)检查暗视状态下无/有眩光时的对比敏感度函数(contrast sensitivity function,CSF)。结果 术后1、3、6个月等效球镜度数分别为(-0.60±0.77)D,(-0.48±0.77)D,(-0.34±0.53)D,与术前(-15.53D±3.65D)差异均有显著统计学意义(P均〈0.001),最佳矫正视力(IogMAR)分别为0.064-0.12,0.02±0.09,-0.003±0.08,与术前(0.21±0.12)差异均有显著统计学意义(P均〈0.001)。术后各空间频率的CS与术前比较有增高趋势。术后3个月6、12、18周/度的CS在无眩光时和有眩光时均明显提高(P均〈0.01),开始接近正常范围。术后3、6个月在各空间频率上CS差异均无统计学意义(P均〉0.05)。结论 ICPIOL植入术矫治高度近视眼可以使CSF恢复到接近正常范围,显著改善视功能,是一种适用于高度乃至超高度近视眼的可供选择的屈光手术。 相似文献
103.
视网膜缺血对兔视神经纤维损害的定量研究 总被引:2,自引:0,他引:2
目的:定量研究视网膜缺血对视神经的损害。方法:通过计算机图像分析定量测算视神经纤维数量;通过前房灌注平衡液,造成超高眼压,形成兔视网膜完全缺血模型,观察视神经纤维数量的变化。结果:正常兔眼平均视神经轴突数为109608±14561(n=22);视网膜缺血眼视神经纤维数量明显减少(P〈0.001)。结论:急性高眼压造成的视网膜缺血可使视神经节细胞及轴突的数量明显减少,应用计算机图像分析可定量检测这种 相似文献
104.
对60例输卵管结扎术后近段闭塞(间质部及峡部)妇女采用改良输卵管子宫角植入术,并对部分病例切除的近段输卵管标本进行病理形态学观察。病理检查发现:①输卵管慢性炎症;②输卵管子宫内膜异位症;③管腔内增生的纤维组织填塞。术后随访50例(83.33%),输卵管通畅46例(92%),宫内妊娠29例(58%),校正妊娠率为63.04%,宫外孕1例,表明宫角植入术用于此类结扎术后输卵管近段闭塞病例的复通有较好疗效。对此术式的关键点及术后宫内妊娠率与绝育年限、年龄、术后输卵管长度的关系作了分析。 相似文献
105.
106.
目的 探究SMILE术后眼压的预测并校正。方法 回顾性研究+前瞻性验证。纳入2019-12/2021-12于中部战区总医院行SMILE的患者90例(180眼),随机抽取30眼为验证集,余150眼为训练集。前瞻性录入2022-01/2022-09SMILE的51例(102眼)为测试集。首先分析训练集手术前3d、术后1wk、1mo、3mo及6mo的眼压情况,确定眼压稳定期及于术前的眼压变化量(ΔIOP);再选取球柱镜代数和(SC)、球镜度(DS)、柱镜度(DC)及眼压(IOP)、中央角膜厚度(CCT)、角膜平均曲率(Km)、前房深度(ACD),眼压稳定时的变化量(ΔCCT、ΔKm、ΔK1、ΔK2、ΔACD)及个体因素,纳入与ΔIOP相关的因素拟合回归模型;最后建立适合临床SMILE术后眼压预测及校正的公式并作效能验证。结果 除术后1wk、3mo及6moIOP三者间无明显差异外,余时段IOP间差异均有统计学意义(P<0.05);各因素与ΔIOP拟合最佳回归方程:ΔIOP=0.459IOP术前-0.183SC-0.041Age+1.292ΔACD-1.270(调节R2=0.533,P<0.001)。仅纳入术前IOP和SC,拟合简化方程:ΔIOP=0.496IOP术前-0.194SC-2.952(调节R2=0.498,P<0.001);预测和校正公式:IOP术后预测=0.5IOP术前+0.2SC+3,IOP术后校正=IOP术后+0.5IOP术前–0.2SC–3。简化公式的效能验证显示良好。结论 SMILE术后3月IOP趋于稳定,且ΔIOP与屈光度相关。SMILE术后IOP可通过简化公式作快速临床预测和校正。 相似文献
107.
6 mandibles were radiographically examined bilaterally to visualise the mandibular canal. 5 imaging techniques were used: periapical radiography, panoramic radiography, hypocycloidal tomography, spiral tomography and computed tomography (CT). Panoramic radiographs were obtained with 2 different X-ray machines. The CT-examinations comprised direct images and standard reconstructions based on axial slices. The specimens were subsequently sectioned for contact radiography. The visibility of the mandibular canal was estimated by 3 observers at special reference points on all radiographs and classified as clearly visible, questionable visibility or not visible. The contact radiographs served as the "gold standard". The inter-observer and the intra-observer agreement were assessed by calculating the overall agreement and the x value. Direct coronal computed tomography, as well as spiral and hypocycloidal tomography, gave better visualisation of the mandibular canal than periapical and panoramic radiography. 相似文献
108.
《The Knee》2022
BackgroundPatellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography.PurposeTo report the postoperative outcomes of patients age 21 and younger treated with particulated juvenile allograft cartilage (PJAC) for full-thickness cartilaginous defects of the patellofemoral joint. The primary aim was to report surgical outcomes and complication rates, as well as return to sport activity. A secondary aim was to provide objective scores of defect restoration by magnetic resonance imaging (MRI) assessment.MethodsA retrospective review of all PJAC cases conducted between 2012 and 2019 at a single tertiary care urban musculoskeletal institution was conducted. Patients 21 years old or younger with minimum clinical follow up of 1 year and postoperative MRI at a minimum of 6 months were included. Cartilage restoration by MRI was independently assessed using the International Cartilage Repair Society’s (ICRS) standardized system.ResultsThirty four patients, 36 knees, were included, with mean age 16.1 ± 3.1 years old. Return to sport rate among patients who participated in a sport preoperatively was 100%. On independent MRI assessment, two thirds of defects achieved an overall grade of normal or nearly normal, while 28 patients (78%) had majority defect fill. Primary graft failure occurred in two cases and one patient experienced a surgical complication.ConclusionRestoration of patellofemoral chondral defects in young patients with particulated juvenile allograft results in satisfactory short-term outcomes and postoperative MRI appearance, along with high rates of return to sport and low rate of complications and graft failure.What is known about the subject: Patellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography. Several cartilage restoration techniques are available, but these rarely achieve the same mechanical properties as native hyaline cartilage. PJAC is a cell-based technique that has demonstrated promise since its introduction in 2007.What this study adds to existing knowledge: This series of patients adds the largest single cohort of pediatric and adolescent patients who receive PJAC for defects of the patellofemoral joint. Surgeons treating patients in this age group should be aware of every technique, and their respective outcomes. 相似文献
109.
Osamu Sakai Yasuhide Nakayama Yasushi Nemoto Yoshihiro Okamoto Taiji Watanabe Keiichi Kanda Hitoshi Yaku 《Journal of artificial organs》2005,8(2):119-124
A novel sutureless vascular connecting system, an assembly with a delivery rod, an introducing sheath, and a connecting device, was developed for easy implantation of small-caliber vascular grafts less than 2 mm in internal diameter. A microporous stainless tube (length 2 mm, external diameter 1.6 mm, wall thickness 65 µm, pore diameter 400 µm, pore-to-pore distance 500 µm) was designed to serve as a connecting device. The feasibility of the system was tested using two types of preliminary animal experiments. One animal model consisted of graft implantation into the rat abdominal aorta (1.5 mm in diameter). The connecting device was inserted into the proximal and distal ends of the aorta through the introducing sheath by pushing the delivery rod with the connecting device placed over it. Subsequently, the aortic segments were inserted into both ends of model grafts made of segmented polyurethane (1.8 mm in internal diameter) and were fixed with banding silk threads from the exterior. The procedure was completed within 20 min without requiring specialized microsurgery techniques. Blood leakage and obstruction did not occur. The second model consisted of an end-to-end anastomosis between rabbit common carotid arteries (2 mm in diameter), which was performed within several minutes of blood flow interruption. Scanning electron microscopy demonstrated that the luminal surface of the device was fully covered with endothelial cells (ECs) after 1 week as a result of transluminal ingrowth of native ECs through the micropores in the device. This endothelialization may prevent early thrombus-induced occlusion. This simple and “easy-to-learn” technique will promote the development of small-caliber arterial grafts, and furthermore, it may have potential for clinical application. 相似文献
110.
The significance of coasting duration during ovarian stimulation for conception in assisted fertilization cycles 总被引:6,自引:0,他引:6
Ulug U Bahceci M Erden HF Shalev E Ben-Shlomo I 《Human reproduction (Oxford, England)》2002,17(2):310-313
BACKGROUND: Withholding gonadotrophin administration and postponing HCG injection, termed coasting, has been suggested as a treatment modality in cases of impending ovarian hyperstimulation syndrome (OHSS). It presents an opportunity to reduce the risk of OHSS and salvage the treatment, without apparent compromise to outcome. However, the duration of the coasting period, which would maintain the advantage without reducing conception rate, has not been fully established. In this retrospective study, we attempted to define the optimal interval of coasting in patients at risk of developing OHSS. METHODS: Patients were grouped according to the number of days elapsed between cessation of gonadotrophins and administration of HCG. Overall, out of 207 patients (mean age 30.76 +/- 0.33 years) coasting lasted 1 day in 39 cycles (18.8%), 2 days in 61 cycles (29.4%), 3 days in 49 cycles (23.6%) and > or = 4 days in the remaining 58 cycles (28.5%). RESULTS: There was no difference between the groups in patients' age, serum estradiol concentrations at the time of HCG administration, oocyte maturity, fertilization and embryo cleavage rates. However, patients in whom coasting lasted > or = 4 days had significantly reduced implantation (10.5%) and pregnancy (26.7%) rates compared with patients with a shorter coasting interval (ranges 18.4-27.9 and 41-55.7% respectively; P < 0.05). CONCLUSION: Coasting for >3 days appears to reduce implantation and pregnancy rates while in-vitro oocyte and embryo quality do not appear to be affected. We suggest that in patients who need coasting for >3 days, cryopreservation of embryos should be considered. 相似文献