INTRODUCTION

Retinopathy of prematurity (ROP) is an avoidable cause of childhood blindness

. Undergoing screening protocols and meticulous examinations by an experienced ophthalmologist is one of the main approaches that could reduce the burden of this type of blindness

. However, later presentation is significantly associated with more advanced ROP. In developing countries and even in rural areas, quite a few patients are still not referred to ophthalmologists until leukocoria is noticed mainly due to lack of routine screening for ROP

.

The surgical techniques for stage 5 ROP are demanding

.Successful anatomical results after surgery are only seen in 9%-45% of cases and, even with a successful anatomical result, the visual outcome may be limited

. Stage 5 ROP was defined as 3 subcategories, according to the International

Classification of Retinopathy of Prematurity, 3

edition, in terms of their anterior and posterior configurations. Stage 5C, was defined as total retinal detachment of closed-funnel configuration accompanied by anterior segment changes (

,marked anterior chamber shallowing, iridocorneolenticular adhesions, corneal opacification)

. There are several studies about surgical management of stage 5 ROP

. However,there is few studies about the management of stage 5C ROP with corneal opacification, which called for urgent surgery to resolve the complications, but is more challenging to manage due to the invisible fundus

. Whether and how to perform surgeries in these cases remain questionable. Regular combined lensectomy and vitrectomy were not advocated due to the corneal opacity and invisible fundus. Here, we presented a series of cases in which staged lensectomy and vitrectomy were performed. Thereafter, the long-term anatomical and visual outcomes were analyzed.

SUBJECTS AND METHODS

This study was approved by the Ethics Committee of Xinhua Hospital, Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China. All parents of the patients provided informed consent before the surgeries were undertaken. Written informed consent was also obtained from the parents for the enrollment of their children in the study.

During long-term follow-up after the two procedures, all the patients formed an anterior chamber. Fourteen eyes had clear corneas after surgery, while 8 eyes retained their corneal opacity. Three eyes had secondary glaucoma, which was controlled by medical treatment. Two eyes had ocular phthisis.The retina was reattached in 3 eyes and partially attached in 11 eyes. The retina of the remaining 8 eyes were detached,including 6 open-open or partially open funnel configurations but expanding and 2 closed configuration detachments. Visual acuities ranged from NLP to HM (Table 2). There were no statistical differences between the mean intervals of the staged surgeries among different groups of post-operative retinal status or the final visual acuity. Table 3 presents the demographics and outcomes of staged lensectomy and vitrectomy in individual patients.

Before lensectomy, all 22 eyes had corneal opacity and flat or disappeared anterior chambers. Eighteen eyes had corneal edema and the remaining 4 eyes had corneal nebula. Two eyes had complicated cataract and 7 eyes had retrolental fibroplasia.Six eyes had posterior pupillary synechiae or membranes.Seven (40%) eyes had vascularly active retinas.

現(xiàn)對本文所提出的算法與ML、SD、Rx-SD和Tx-SD檢測算法在瑞利衰落信道下的蒙特卡羅仿真結(jié)果進行分析，并將所提出的算法的計算復(fù)雜度與ML檢測和傳統(tǒng)的SD檢測包括Rx-SD和Tx-SD進行比較.

All patients underwent comprehensive examinations. Preoperative clinical findings, including the patients’ gestational age at birth and surgeries, birth weight, gender, manner of delivery, ROP status, pre- and post-operative status, and treatment were recorded.

以上主要論述了通過回應(yīng)型法模式實現(xiàn)刑法教義學知識對處罰實質(zhì)合理性的回應(yīng)，屬于一種宏觀的理念介紹和法理論證，如何具體實現(xiàn)這種“回應(yīng)”，就需要結(jié)合犯罪構(gòu)成體系本身。

We performed staged lensectomy and posterior vitrectomy in all 22 eyes. Lensectomy was performed firstly to avoid further deterioration. Topical steroids were applied to reduce the corneal edema after lensectomy. Vitrectomy was advocated if the corneal edema improved and the fundus was visible during the follow up after lensectomy. All the patients were operated on by one surgeon (Zhao PQ). All the eyes were followed for at least three years post-operatively (average 8.9±2.6y).

In our case series, all the stage 5C ROP cases had flat or disappeared anterior chambers, which indicated an urgent need for lensectomy to avoid permanent corneal damage. However,all the eyes had corneal opacity due to corneal edema or dense corneal nebula, which made it difficult to view the fundus clearly to perform vitrectomy. Additionally, in our case series, 7 eyes had vascularly active retinas. If vitrectomy is performed when the retina is vascularly, severe complications such as vitreous hemorrhage may occur

. Gopal

and Fuchino

suggested that since the disease was more vascularly active in babies less than 6 months of age, operating within 6mo has a marked risk of post-operative hemorrhages.Machemer and DeJuan

and Cusick

reported a higher success rate when babies were operated after six months of age. Anti-angiogenic treatment can possibly be an adjunctive therapy for vascularly active retina

, however, eyes must be monitored closely since intense fibrous contraction with complex retinal detachments can occur

. Staged lensectomy can rescue the cornea in stage 5C ROP and also avoid the risk of post-operative hemorrhages when the retina is vascularly active. The mean interval between the two staged surgeries in our study was 6.8±4.6mo, ranging from 2.5 to 18.5mo, which depended on the status of the corneal opacity and the vascular activity of the retina. Treatment with topical anti-inflammatory drops may be considered after lensectomy to reduce the corneal edema.

Staged lensectomy and vitrectomy(Figure 1).

Primary procedure: lensectomy (Online supplementary Video 1): 1) Apply the two-port limbal approach; 2) Drain the subretinal fluid to soften the eyeball if necessary. Then, inject viscoelastics into the anterior chamber to separate the anterior and posterior iris synechiae. Trim the edge of the iris to enlarge the pupil. 3) Perform lensectomy; 4) Remove the anterior capsule and aspirate the lens material under low suction using the vitrectomy cutter.

The authors also demonstrated that staged lensectomy and vitrectomy for stage 5C ROP with opaque cornea might be beneficial in helping preserve vision. The purpose of the surgeries is to rescue the cornea and even partly attach the retina with less complications

. Surgical intervention may prevent further ocular atrophy, improve the appearance of the eye, and somehow restore visual function (

, perception of light)

, which is very important to the patients with lowvision.

Follow-up examinations were conducted periodically. The anatomical outcomes were evaluated, including retinal status,cornea, and anterior chambers (Figure 3). Visual acuity was measured accordingly, marked as hand motion (HM), light perception (LP), and no light perception (NLP).

RESULTS

The demographics of the patients are presented in Table 1.Twenty-two eyes of 18 stage 5C ROP patients with advanced complications were included in this study. Eight patients were males and 10 were females. Their birth weight ranged from 940 to 2000 g (mean 1363.0±300.0 g). Gestational age (GA) at birth ranged from 27 to 32wk (mean 29.3±1.6wk). The average corrected GA at the time of the first surgery was 73.6±18.0wk(ranging from 50 to 123wk). The average corrected GA at the secondary vitrectomy was 102.4±21.3wk (ranging from 69 to 143wk). The mean interval between the two surgeries was 6.8±4.6mo (2.5-18.5mo).

根據(jù)當陽市水域灘涂承載力評價和水產(chǎn)養(yǎng)殖產(chǎn)業(yè)發(fā)展預(yù)測，我們以市場需求為導(dǎo)向，以資源稟賦為基礎(chǔ)，按照 “突出重點、有序推進、優(yōu)化結(jié)構(gòu)、因地制宜、協(xié)調(diào)發(fā)展”的總體要求，規(guī)劃當陽市養(yǎng)殖水域灘涂開發(fā)的總體思路，逐步優(yōu)化漁業(yè)產(chǎn)業(yè)區(qū)域布局，建立協(xié)同發(fā)展產(chǎn)業(yè)格局。

學生宿舍的條件很差，窗玻璃又不斷地被打碎，秋天里，四處漏風，只好糊上報紙，風一吹，呼答答地響起沒完沒了，尤其在深夜，感覺像睡在押運戰(zhàn)俘的列車上。這些沒玻璃的窗戶只有等到大雪紛飛、北風呼號的日子才能重新鑲上。

This study was a retrospective, interventional,consecutive case series. Twenty-two eyes of 18 stage 5C ROP patients with corneal opacification who underwent staged lensectomy and vitrectomy at Xinhua Hospital, Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai,China, from 2008 to 2017 were included in this analysis.

DISCUSSION

In this study, we recommended staged lensectomy and vitrectomy as an alternative choice. Lensectomy was performed first. Then, vitrectomy was recommended if the corneal opacity was alleviated and the fundus was visible during the follow-up period after lensectomy.

在前面確定精選pH值條件下，進行調(diào)整劑水玻璃用量試驗。試驗結(jié)果見圖9。從試驗結(jié)果可以看出，當水玻璃用量在200g/t時，精礦產(chǎn)品中銅、鉬的回收效果較好，隨著用量繼續(xù)增加，銅、鉬逐漸受到抑制。

Closed vitrectomy combined with lensectomy were performed in stage 5 ROP with retrolental fibroplasia or other complications,such as a flat anterior chamber or cataract. Whether surgical intervention is necessary in these cases remains questionable

.When making a surgical decision, controversies still exist regarding when the surgery should be performed and which surgical techniques are the most beneficial for the treatment of stage 5 ROP with advanced complications. Combined vitrectomy and lensectomy are not advocated for stage 5C ROP eyes with invisible fundus due to corneal opacity.

Surgical intervention in ROP has been described as early as 1977 by Treister and Machemer

. Two common surgery approaches used in stage 5 ROP are open-sky vitrectomy and closed vitrectomy

. Open-sky vitrectomy has the advantage of allowing two-hand dissection from a larger anterior incision; however, the maintenance of intraocular pressure(IOP) during surgery may be difficult, and there is a risk of corneal rejection post-operatively after re-suturing the cornea. Due to this, the focus has gradually shifted to closed vitrectomy with or without lensectomy

.

江豚與大熊貓一樣憨態(tài)可掬，吻部短而闊，看起來就像一直在微笑。2006年，中科院水生生物研究所科考時發(fā)現(xiàn)，長江江豚有1800頭左右，其中1000多頭生活在長江干流。到了2012年，江豚數(shù)量銳減至1000頭。2013年，世界自然保護聯(lián)盟紅色名錄將長江江豚定為“極度瀕?！蔽锓N。

In our case series, all the patients had normal anterior chambers after surgery. Fourteen out of 22 eyes had clear corneas post-operatively. Secondary glaucoma has been reported to be another complication of ROP

, in our study,3 cases had complicated glaucoma and were under medical control. Fourteen (63.6%) eyes obtained at least partial retinal reattachment after the second procedure, the successful anatomical result was higher than the result (57%) reported in the previous study with 87 eyes by Choi and Yu

.

Second procedure: vitrectomy (Figure 2, Online supplementary Video 2).Vitrectomy was performed when the corneal edema alleviated and did not obscure the view of the retina and/or the retina turned vascularly inactive. 1) Apply the three-port limbal approach; 2) Remove the pre-retinal tissue completely without retinal break formation using 23/25G intraocular forceps and scissors through bimanual dissection under coaxial illumination of the microscope; 3) Inject the viscoelastic solution to achieve retinal reattachment and to maintain the eyeball pressure at the end of the surgery. Use silicone oil tamponade in the surgery if retinal break was present during vitrectomy. 4) Suture the sclerotomies.

作為以漢語為母語的中國，在學習英語的過程中首先要解除48個因素，但是小學階段學生可能在初次接觸這類知識的過程中會產(chǎn)生陌生感。為此，就需要教師能夠在日常教學過程中多聽多看。以此進一步培養(yǎng)學生形成語感。

印度素食文化直接影響當?shù)芈糜螛I(yè)的形式表現(xiàn)為兩點，一是傳統(tǒng)素食節(jié)日；二是全素食城市——帕利塔納吸引來的旅游人群。

Our study has several limitations. First, it was a retrospective and non-comparative consecutive case series study. Second,the study was based on one surgeon’s experience.

In conclusion, the management of the condition of stage 5C ROP patients with flat anterior chamber and central corneal opacity is challenging. Staged lensectomy and posterior vitrectomy are procedures that can prevent further complications, such as corneal endothelium decompensation,leukoma, and secondary glaucoma. Surgical intervention can achieve a favorable retinal status to some extent and preserve some useful eyesight in advanced ROP cases.

The authors thank all the patients who were enrolled in the study.

Supported by the National Natural Science Foundation of China (No.81770963; No.81770964).

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