RESUMO
Aims: The aim was to analyze the learning curve of phacoemulsification (phaco) performed by residents without experience in performing extra‑capsular cataract extraction (ECCE) in a step‑by‑step training program (SBSTP). Materials and Methods: Consecutive surgical records of phaco performed from March 2009 to Sept 2011 by four residents without previous ECCE experience were retrospectively reviewed. The completion rate of the first 30 procedures by each resident was calculated. The main intraoperative phaco parameter records for the first 30 surgeries by each resident were compared with those for their last 30 surgeries. Intraoperative complications in the residents’ procedures were also recorded and analyzed. Results: A total of 1013 surgeries were performed by residents. The completion rate for the first 30 phaco procedures was 79.2 ± 5.8%. The main reasons for halting the procedure were as follows: Anterior capsule tear, inability to crack the nucleus, and posterior capsular rupture during phaco or cortex removal. Cumulative dissipated energy of phaco power used during the surgeries was significantly less in the last 30 cases compared with the first 30 cases (30.10 ± 17.58 vs. 55.41 ± 37.59, P = 0.021). Posterior capsular rupture rate was 2.5 ± 1.2% in total (10.8 ± 4.2% in the first 30 cases and 1.7 ± 1.9% in the last 30 cases, P = 0.008; a statistically significant difference). Conclusion: The step‑by‑step training program might be a necessary process for a resident to transit from dependence to a self‑supported operator. It is also an essential middle step between wet lab training to performing the entire phaco procedure on the patient both effectively and safely.
RESUMO
BACKGROUND: Human β-defensin is mainly located in various tissues epidermis or epithelium, also exists in ocular surface, but its ocular surface and its role of ocular surface diseases remain poorly understood.OBJECTIVE: To observe the distribution of human β-defensins in ocular surface tissue, and to analyze their potential effects on ocular surface disease. DESIGN, TIME AND SETTING: In vitro controlled observation with regard to ocular surface tissue was performed at the Central Laboratory, Xinhua Hospital, Medical College of Shanghai Jiao Tong University and Cell Biochemistry Institute, Chinese Academy of Sciences Shanghai Branch, between October 2006 and December 2007.MATERIALS: A total of 18 inflammatory conjunctival specimens consisted of 6 pterygium surface bulbar conjunctiva, 4 bulbar conjunctival cysts, 4 acid burn conjunctiva, 2 thermal burn conjunctiva and 2 conjunctival granuloma; 15 inflammatory corneal specimens included 6 viral keratitis, 4 fungal keratitis, 3 bacterial keratitis and 2 eye removal following corneal perforation; 9 cadaver normal bulbar conjunctiva samples, 8 cadaver normal corneal samples. METHODS: RT-PCR method and immunohistochemistry were applied to detect human β-defensin expression in 50 samples. MAIN OUTCOME MEASURES: Distribution and location of human β-defensin proteins in normal and inflammatory ocular surface tissues. RESULTS: RT-PCR showed that human β-defensin 1 and human β-defensin 3 were positive in all of the tested samples, whereas human β-defensin 2 existed in a majority of inflammatory ocular surface tissues and no expression was observed in normal ocular surface tissues. Immunohistochemistry analysis revealed most of inflammatory ocular surface tissues expressed human β-defensins 1 and 2, distributing in epithelial cell layer and predominantly in basal lamina, occasionally infiltration of stromal cells was observed, only a small number of human β-defensin 2 expression was absent; normal cornea and conjunctiva samples presented with human β-defensin 1 expression, distributing in epithelial cells and predominantly in basal lamina, only few expressed human β-defensin 2.CONCLUSION: Human β-defensin 1 and 3 appear to be constitutively expressed in surface epithelial cells and basal lamina of normal and inflammatory ocular surface tissues, while human β-defensin 2 may be induced to express in the majority of inflammatory ocular surface tissues. Three human β-defensins expression plays a pivotal role in preventing ocular surface infection and promoting ocular surface injury repair.
RESUMO
Objective Corneal endothelial decompensation is caused by many corneal diseases. It often results in severe clinical complications. Endothelial keratoplasty (EK) is a new therapy for corneal endothelial decompensation. This study aimed to investigate a new approach to establishing corneal endothelial decompensation animal model with Descemetorhexis technique in order to better understand the tissue response to EK. Methods Thirty New Zealand white rabbits were randomly divided into three groups according to different surgical procedures; corneal endothelial cells (CEC), Descemet's membrane and corneal endothelial cells (DM + CEC) as well as Descemet' s stripping with endothelial keratoplasty(DSEK) group and 10 eyes for each. The right eyes of rabbits were as surgery eyes. Other 10 rabbits were as DSEK donors. Corneal transparency, anterior chamber response and graft location were examined once per day for two weeks under the slit lamp. Comeal thickness was measured by ultrasound biomicroscope. Corneal endothelial cells were analyzed using vital staining with alizarin red and trypan blue in 2, 4 and 8 weeks after operation. Results The cornea in DM + CEC group remained opaque throughout the observation period. In CEC and DSEK group, corneal clarity was gradually restored and corneal thickness was significantly less than that in the DM + CEC group during the postoperative 8 weeks. There were significant differences in corneal thickness between the DM + CEC group and CEC group or DSEK group during the postoperative 8 weeks (P ＜0. 05). The vital staining showed that most Descemetorhexis area was not covered by endothelial cells even 2 months after surgery. Conclusion A new corneal endothelial decompensation model is successfully established for the study of corneal endothelial keratoplasty, which is helpful for understanding the wound-healing of rabbit corneal endothelium after Descemel' s membrane damage.
RESUMO
BACKGROUND: Intraocular contract lens (ICL) implantation emerges as a crystal refrangibilit operation to rectify and cure high myopia in recent years. Collagen, a new material, is consisted of collagen Ⅳ and aquagel in Starr Company. It is an ideal material for ICL; however, high price is restricted to its development at a certain degree.OBJECTIVE: To find out ideal method of collagen ICL implantation through animal experiment in rabbit eyes and evaluate intraocular biocompatibility by observing inflammatory reaction and variation of inflammatory mediators.DESIGN: Single exponent and opening study.SETTING: Department of Ophthalmology, Xinhua Hospital affiliated to Medical College of Shanghai Jiaotong University.MATERIALS: The experiment was carried out in Xinhua Hospital affiliated to Medical College of Shanghai Jiaotong University and Shanghai Nanyang Radio-immunity Testing Center from August 1999 to March 2000.Twenty New Zealand rabbits were divided into three groups according to randomly digital table: ICL implantation group (n=8), operative control group (n=6) and blank control group (n=6).METHODS: ① Right eyes of rabbits in ICL implantation group were suffered from ICL implantation and peripheral operation of iris [1]; however,right eyes of rabbits in operative control group were only suffered from peripheral operation of iris. After operation, hormone-antibioltic eyedrops were dribbled into eyes four times a day for total 10 days. At 1, 4 and 7days after operation, 2.5 mg dexasone + 40 000 U cidomycin were subconjunctivally injected into eyes. Rabbits in black control group did not receive any operation. ② At 1, 4, 7, 14 days and 1 month after operation,indexes of operative eyes in ICL implantation group and operative control group were measured including luctuation of intraocular pressure, damage of corneal endothelium, protein leakage in anterior chamber, depth of anterior chamber, hyphema, posterior synechiae of iris, ICL decentration and lens opacity. ③ At 1, 4, 7, 14 days and 1 month, samples of aqueous humor were aspirated from operative eyes of rabbits in ICL implantation group, operative control group and blank control group. Radioimmunoassay (RIA) was used to examine the concentration of prostaglandin-E2 (PGE2)in aqueous.MAIN OUTCOME MEASURES: ① Results of reaction in anterior chamber at each time point before and after operation; ② results of PGE2 concentration of inflammatory mediators in aqueous humor after operation.RESULTS: All 20 rabbits were involved in the final analysis. ① Changes of intraocular pressure at each time point before and after operation: As compared with that before operation, intraocular pressure was not changed in ICL implantation group and operative control group at each time point after operation (P ＞ 0.05). ② Damage of corneal endothelium and leakage in anterior chamber after operation: ICL implantation group: Five eyes were shown as shallow anterior chamber at various degrees on the first day after operation, and recovered normally within 1 week; hemorrhage was observed in anterior ch amber of two eyes and absorbed after 2 weeks; two eyes had anterior and posterior synechiae of iris, respectively, and pupil was deformed slightly; ICL decentration at various degrees was observed in two eyes; point-like opacity was observed in anterior bursal membrane of crystal in one eye after 1 month. Operative control group: Leakage of grade 1-2 was observed in 6 eyes on the first day after operation and was absorbed within 1 week. Cornea was clearing, and hyphema, shallow anterior chamber, posterior synechiae of iris and lens opacity were not changed. ③ PGE2 concentration of inflammatory mediators in aqueous humor after operation:PGE2 oncentration was the highest in ICL implantation group at 1-4 days after operation, and then it was decreased gradually; however, PGE2 concentration was similar at 14 days and 1 month after operation (P＞0.05).CONCLUSION: There is no obvious occurrence of chronic uveitis in anterior chamber after ICL implantation. PGE2 concentration in anterior chamber is decreased gradually, and this suggests that a classic foreignbody granulomatous inflammation emerges after ICL implantation, which reflects a good tolerance of ICL for ocular tissue.
RESUMO
BACKGROUND: A new type of materials, Collamer, is polymerized with type V collagen and HEMA by Staar company, which is a good material for the establishment of intraocular contact lens(ICL). There is no similar material in our country.OBJECTIVE: To evaluate the biocompatibility of ICL made mainly by collagen-polymer in animals.DESIGN: A randomized controlled trial.SETTING: Testing Center of Shanghai Institute of Biomaterial.MATERIALS: Our study was conducted in the Testing Center of Shanghai Institute of Biomaterial from January 2000 to April 2000. Cell strain: hearty L-929 cells(fibroblast of mouse) after 48-72 hours of passage; Twenty white guinea pig of either gender aged between 1 month and 3 months with a body mass between 300 g and 500 g; Seven healthy adult New Zealand rabbit of either gender(female rabbits were not required pregnant for pyrogenic reaction test) with a body mass between 1.7 kg and 3.0 kg or between 2.5 kg and 3.5 kg(experimental animals were obtained from Shanghai experimental animal center, ordinary grade).INTERVENTIONS: Collagen was used to perform the following biological tests: ① cytotoxicity test (cell growth rate); ② anaphylaxis test; ③ pyrogenic reactions test; ④ subcutaneous implant test. The data were analyzed and evaluated according to criteria.MAIN OUTCOME MEASURES: ① Growth and proliferation of fibroblast in mice; ② Reactions of erythema and edema of every provocation site and every observatory time after the induction of intradermal injection and local patch test; ③ Increase of body temperature of the rabbit after the injection of the extraction of the material into auricle marginal vein; ④ Reactions around the materials after 4 weeks of collagen implantation in rabbits subcutaneously.RESULTS: ① Cytotoxicity test: relative growth rate of collagen group was 99％ to 106%, and the toxicity grade was level 0 - 1. ② Anaphylaxis test:there was no erythema or edema reaction at every provocation site at each time point of collagen group. The skin reaction to collagen-polymer was level 0. ③ Pyrogenic reactions test: the temperature increased in rabbit was below 0.6 ℃ and the total increase of the temperature was below 1.4 ℃ in rabbits. ④ Subcutaneous implant test: there was very little lymphocyte infiltration around the sample in both collagen group and control group with Level I inflammatory reaction. And the evaluation of the formation of fiber cyst was level I.CONCLUSION: Results of material biological evaluation tests demonstrate that this collagen-polymer has high biocompatibility, and can become an ideal material for ICL.