太空“眼科手术”——记“哈勃”的最后一次在轨维修

“哈勃”空间望远镜于1990年4月25日登天．由光学系统．科学仪器和辅助系统三大部分组成．另外还有2副太阳电池帆板和2个抛物面天线。中间圆筒是望远镜的主体，圆筒前部是光学系统。

Amniotic membrane transplantation for porous sphere orbital implant exposure

Objective: This study is aimed at describing the clinical outcome of amniotic membrane transplantation for exposure of porous sphere implants. Methods: A retrospective review of consecutive cases of porous sphere orbital implant exposure was carried out. Eight cases were presented between May 2004 and Oct. 2006 (5 males, 3 females; mean age 44.5 years). Six had enucleation and two had evisceration. Exposure occurred in two primary and six secondary. Orbital implant diameter was 22 mm in seven cases and 20 mm in one case. Six patients are with hydroxyapatite and two with high-density porous polyethylene (Medpor) orbital implants. The mean time from implantation to exposure was 1.1 months (range 0.8~2 months). All patients required surgical intervention. Results: The time of follow-up ranged from 3.0 to 28.0 months (mean 16.5 months). Amniotic membrane grafting successfully closed the defect without re-exposure in all of these patients. The grafts were left bare with a mean time to conjunctiva of about 1 month (range 0.8~1.5 months). Conclusion: Exposed porous sphere implants were treated suc-cessfully with amniotic membrane graft in all of patients. The graft is easy to harvest. This technique is useful, dose not lead to prolonged socket inflammation and infection, and it is valuable application extensively.

Iris recognition:a biometric method after refractive surgery

Iris recognition,as a biometric method,outperforms others because of its high accuracy. Iris is the visible internal organ of human,so it is stable and very difficult to be altered. But if an eye surgery must be made to some individuals,it may be rejected by iris recognition system as imposters after the surgery,because the iris pattern was altered or damaged somewhat during surgery and cannot match the iris template stored before the surgery. In this paper,we originally discuss whether refractive surgery for vision correction(LASIK surgery) would influence the performance of iris recognition. And experiments are designed and tested on iris images captured especially for this research from patients before and after refractive surgery. Experiments showed that refractive surgery has little influence on iris recognition.

EFFECTS OF PREOPERATIVE SOFT CONTACT LENS WEAR ON HIGHER-ORDER ABERRATIONS AFTER LASER IN SITU KERATOMILEUSIS

Objective To evaluate the effects of preoperative soft contact lens (SCL) wear on higher-order aberrations(HOAs)correction after wavefront-guided and conventional laser in situ keratomileusis (LASIK). Methods A prospective randomized double-masked comparative study was conducted in 180 eyes of 90 patients scheduled for LASIK, including 92 eyes of 46 patients with previous SCL wear. The patients were divided into four groups: no SCL-conventional group, SCL-conventional group, no SCL-wavefront group and SCL-wavefront group. Preoperative and postoperative examinations included uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), contrast sensitivity and HOAs. Results The UCVA and BSCVA were 20/20 in all patients at 6 months postoperatively. And 36.3%, 22.7%, 18.1% and 35.4% gained one line or more of BSCVA in no SCL-wavefront group, SCL-wavefront group, no SCL-conventional group and SCL-conventional group, respectively. Both the safety index and efficacy index surpassed one in 4 groups and were highest in no SCL-wavefront group. The increase in root-mean-square (RMS) values of HOAs was significantly lower in no SCL-wavefront group and higher in SCL-wavefront group. At 6 months postoperatively, the increase in RMS of HOAs (RMSh) were 0.67, 1.58, 1.17 and 1.28 in no SCL-wavefront group, SCL-wavefront group, no SCL-conventional group and SCL-conventional group, respectively. Conclusion Preoperative contact lens wear has significant influence on the efficacy of HOAs correction in wavefront-guided LASIK. Patients with contact lens wear preoperatively should be cautious when scheduled for wavefront-guided LASIK.

Pattern of ocular trauma among the elderly in Kashan, Iran

Objective：Ocular trauma is a common cause of visual impairment and accounts for 38% to 52% of all patients presenting as ophthalmic accident and emergency cases to the hospital.The purpose of this study is to describe the pattern of ocular injuries that leads to hospitalization in the elderly in Kashan,Iran.Methods：In the retrospective consecutive case series,a total of 94 geriatric patients （≥ 65 years） who admitted and underwent management for ocular trauma from April 2001 to March 2011 at Matini Hospital of Kashan,the only center of eye surgery in the region of Kashan,were reviewed.The items include age,sex,injury mechanism,site and extent of damage,presenting and final best corrected visual acuity at least 3 months after trauma,which were reviewed and analyzed with SPSS software.Results：During the 10 years,94 eyes of 94 patients with ocular trauma were included.Mean age of patients was （77.5±5.1） years （range 65 to 102 years）.Male to female ratio was 2.76.The mechanism of ocular injury included sharp trauma in 56 patients （59.6%） and blunt in 38 patients （40.4%）.Trauma occurred mostly in males （69 patients,73.4%） and at the work place （38 patients,40.4%）.On admission the visual acuity in 50 patients （53.2%） with damaged eyes was light perception to hand motion.While the final best corrected visual acuity in 36 patients （38.3%） was better than hand motion.Conclusion：Ocular trauma is a serious cause of visual impairment in the elderly.Appropriate and timely management may improve their visual prognosis.

Epidemiology of eye injuries sustained by military personnel in China

Objective： To investigate the epidemiological characteristics of eye injuries sustained by military personnel in Chinese army. Methods： Eleven military evacuation hospitals located in different regions were selected for this study. We reviewed all the medical records of eye injuries sustained by military personnel between January 2005 and December 2009. Patients＇ information was collected. All data were put into database and analyzed statistically. Results： Totally there were 415 inpatients with eye injuries （442 eyes） and their mean age was 24.40 years. Eye injury accounts for 13.51% of all eye diseases in this study. From 2006 to 2009, the number of eye injury increased gradually. Among them, 175 （42.17%） were injured in leisure time, and 145 （34.94%） in working time. Twenty-two （5.30%） patients had an eye surgery or history of eye disease before injury. In all, 246 patients （59.28%） were sent to evacuation hospital within 24 hours and 64 （56.64%） underwent surgeries in 24 hours after injury. There were 389 patients （93.73%） hospitalized for 1 time. Visual acuities of 187 eyes （42.31%） were grade 1 （≥ 20/40） after injury. When discharge, 349 eyes （78.96%） obtained a visual acuity of grade 1. Conclusion： Eye injury has a very frequent incidence in Chinese army and much more attention should be paid to prevent it.