Open-globe injuries (OGI) result in complicated and diverse conditions with different mechanisms and anatomical locations, which lead to completely different outcomes based on when to perform pars plana vitrectomy (PPV) after trauma. The PPV operation time points are generally divided into early (0 - 3 days), delayed (4 - 14 days), and late (> 2 weeks). There are still some controversies about the PPV time points after OGI. Injuries with intraocular foreign bodies or high risk of infection usually need early surgery to reduce the occurrence of endophthalmitis. However corneal edema and vitreous hemorrhage can increase the difficulties for early diagnosis and surgery. If there is choroidal hemorrhage or severe trauma in the back part of the eye, delayed intervention can allow the blood clots to be liquefied and removed easily. But there is higher incidence of postoperative complications. Late surgery can reduce the difficulty of PPV, but the increased incidence of proliferative vitreoretinopathy may lead to severe retinal traction, tears and postoperative scar formation.
PURPOSE:To evaluate the activitv of protein kinase C(PKC) in response to retinal photochemical insult in rat. Furthermore, to investigate the effect of dexamethasone(DXM ) on PKC activity. METHODS :The experiments were performed on 48 SI') rats whieh were separated into two groups,control and treated groups,and the latter received daily intraperitoneal injections of DXM (1 mg/kg)for 5 consecutive days,starting 3 days before light exposure. The animals were continually exposed to green fluorescent light (510nm~560nm) with an illuminance level of (1 900plusmn;106.9)lx for 24 hrs.The retinal enzyme activity of PKC was tested at 6 hrs,1 day,3 days,7 days,and 14 days after light exposure respectively. RESULTS:In animal models,PKC activity showed a transient increase in both groups at 6 hrs after light exposure and then decrease persistently there alter. The activity of PKC was unresponsive to DXM intervention. CONCLUSIONS :These results suggested that the persistent lower PKC activity might result in disturbance of retinal function in rat retinal photochemical injury. （Chin J Ocul Fundus Dis,1997,13: 78-80）
Objective To further investigate pathologic mechanism of retinal phototrauma. Methods Twenty Wistar rats were divided into control and experimental groups.Their eyes were extracted in 12，24 and 36 hours after light exposure.HE stained retina samples were examined and TDT-mediated dUTP nick end labelling(TUNEL)method was employed to distinguish apoptotic cells. Results After 12-hour light exposure,slight vesiculation was observed in the rod outer segment of the retinas.After 24-hour light exposure,the outer nuclear layer showed predominant fractured and condensed nuclei and fragmented DNA.After 36-hour light exposure,the rod outer and inner segments were lysed and most of the nuclei in the outer nuclear layer were disappeared. Conclusions Apoptosis of photoreceptor cell is one of the important mechanisms which cause experimental retinal photoinjury of rats. (Chin J Ocul Fundus Dis, 1999, 15: 167-169)
ObjectiveTo investigate the effect of blue light on Ca2+-protein kinase C (PKC) signaling pathway in human retinal pigment epithelial (RPE) cells in vitro. MethodsPrimary human RPE cells were cultured in vitro and characterized. The experiments were carried out using the 4th generation of human RPE cells. The PKC protein level was measured by Western blot to determine the most appropriate concentration of phorbol ester (PMA) and calcium phosphate binding protein (calphostin C) on PKC expression. Non-radioactive isotope method was used to determine the effect of blue light on PKC expression of cultured cells. Blue-light damage model of human RPE cells was established by 6 hour irradiation of medical blue-light lamp [20 W, 450-500 nm wavelength, (2000±500) Lux], and 24 hours prolongation of post-exposure culture. The human RPE cells were randomly divided into 5 groups. Group A did not receive light irradiation, group B only received blue light irradiation, group C was blue light irradiation and 0.1 mmol/L nifedipine treatment, group D was blue light irradiation and 100.0 nmol/L calphostin C treatment, group E was blue light irradiation and 100.0 nmol/L PMA treatment. Intracellular Ca2+ concentration was measured by acetoxymethyl ester (Fluo 3-AM) labelling and confocal microscope imaging. ResultsThe PKC protein expression in 100.0 nmol/L or 200.0 nmol/L PMA-treated groups was higher than 0.1, 1.0, 10.0, and 50.0 nmol/L PMA-treated groups, the difference was statistically significant (F=217.537, P<0.05), but there was no statistically difference between 100.0 nmol/L and 200.0 nmol/L PMA-treated groups (P=0.072). The PKC protein expression in 100.0 nmol/L or 200.0 nmol/L calphostin C-treated groups was lower than 5.0, 25.0, 50.0, and 75.0 nmol/L calphostin C-treated groups, the difference was statistically significant (F=164.543, P<0.05), but there was no statistically difference between 100.0 nmol/L and 200.0 nmol/L calphostin C-treated groups (P=0.385). PKC level in blue light group was higher than non-light group, the difference was statistically significant (t=-9.869, P<0.05). The Ca2+ fluorescence intensity values in group B, C, D and E was higher than group A, the difference was statistically significant (F=26 764.92,P<0.05). The Ca2+ fluorescence intensity values in group E was higher than group B, C and D (P<0.05), and that in group B was higher than group C and D (P<0.05). ConclusionsThe PKC activity and intracellular Ca2+ concentration in human RPE cells increase after blue-light irradiation. Both calcium channel inhibitor nifedipine and PKC inhibitor calphostin C can reduce intracellular Ca2+ concentration in human RPE cells. PMA can induce intracellular Ca2+ concentration in human RPE cells after blue light irradiation.
Purpose To observe the changes of choroidal circulati on and the retinal lesions caused by ocular contusion with indocyanine green ang iography (ICGA). Methods ICGA examination was performed on 30 cases (30 eyes) of various traumatic condition in conjunction with fundus fluorescein angiography (FFA). Results FFA of 19 cases (63.3%) showed the hypofluorence in quadrant or whole disc in accordance with the area of delayed filling of choroid. Twentysix cases (86.2%) showed d efected choroidel perfusion in ICGA,among them 16 cases showed localized delayed perfusion, in which the shortest perfusion time was 1 min 50 s and the l ongest time was 5 min.43 s,and 10 patients showed localized perfusion defect,and reversed filling time of retinochoroid vessels in 6 patients. Five cases (16.6%) had delayed filling time in both choroidal and central retinal vessels . Damage of retinal pigment epithelium was found in the areas of choroidal abnor mal perfusion. Conclusion ICGA combined with simultane ously FFA, is valuable in evaluating blunt injury of the ocular fundus and ben eficial to its diagnosis and treatment. (Chin J Ocul Fundus Dis, 2001,17:122-124)
Objective To observe the clinical characteristics of severe ocular detonator explosive injuries and to evaluate the therapeutic effects of vitrectomy on it. Methods Clinical data of 37 consecutive patients (65 eyes) with severe ocular detonator explosive injuries were retrospectively analyzed. The patients included 36 males and 1 female with the average age of 28.6 years. The biocular injuriy was in 31 cases (83.8 %), and one-eyed injury was in 6 cases (16.2%). A total of 48 eyes had severe explosive injury. The visual acuity was no light perception in 9 eyes in which 3 eyeballs were obviously atrophic, light perception in 28 eyes, hand moving in 4 eyes, and counting finger/33 cm in 7 eyes. Vitrectomy was performed on 46 eyes, in which 41 had severe ocular explosive injury. There were no vitreous surgery indications in 13 eyes of 19 eyes didnprime;t undergo surgery; the other 6 eyes didnprime;t undergo surgery due to the atrophic eyeballs or economic reasons. The treating time after trauma was within 1 week in 7 patients (18.9%), 1 week to 1 month in 13 (35.2%), and more than 1 month in 17 (45.9%). The follow-up duration lasted 6 months to 2 years after operation with the average of 8.6 months. Results In 65 eyes, the occupation ratio of conjunctival foreign bodies was 66.2%; corneal foreign bodies was 46.2%; vitreous hemorrhage was 70.8%; intraocular foreign bodies (IOFB) was 69.2%; retinal shocking injury or optic nerve blasting injury was 56.9%. The visual acuity improved in 33 eyes, remained unchanged in 25 eyes, and decreased in 7 eyes. In 46 eyes which had undergone vitrectomy, IOFB injuries was in 35 eyes (76.1%); the visual acuity increased in 26 eyes (59.5%), remained unchanged in 13 eyes (28.3%), and didnprime;t cure in 7 eyes (15.2%) in which 2 eyes underwent ocular enucleation and 5 eyes were atrophic. The increasing rate of visual acuity in the patients who accepted the treatment more than 1 month after injury was low. The occupation ratio of monocular blindness was 51.4% and biocular blind was 8.1%. Conclusions Most of severe ocular explosive injuries by detonator are with IOFB. causes of the high blinding rate are late treatment and serious injury. Strengthening the diagnosis and treatment of retinal shock and optic nerve blast, and performing vitrectomy as soon as possible can improve prognositc visual function of injured eyes.
Objective To evaluate the visual results,surgical tec hnique and safety of secondary intraocular lens (IOL) implantation in aphakic eyes following vitrectomy and lensectomy for complicated ocular trauma or retinal detachment． Methods The clinical records of 3 2 cases (32 eyes),received these surgeries during November 1996 and December 1999,were reviewed retrospectively.During the secondary operation，intraocular infu sion through the pars plana was performend and the type of IOL was chosen based on the integrity of lens capsule. Results The study included 30 eyes suffering from trauma (foreign bodies in 15 eyes,penetrating injury with traumatic endophthalmitis and with vitreous hemorrhage in 6 eyes respectively, blunt trauma with lens dislocation in 3 eyes),and 2 eyes with primary retinal detachment.Those eyes all received vitrectomy,lensectomy,and/or remova l of foreign bodies and corneal suture.The interval of two operations ranged from 1 to 16 months with an average of 6.8plusmn;3.7 months.Posterior chamber IOL was implanted in the ciliary sulcus in 25 eyes with a whole or 2/3 of lens capsule,trans scleral suture fixation of IOL in 5 eyes,anterior chamber IOL and IOL with artificialiris in one eye respectively.Silicone oil was removed in 5 eyes duri ng the secondary operation.Post-operative visual improvement was achieved in 29 eyes.Main complications were corneal edema and low intraocular pressure after operation. Conclusion Intraocular infusion and proper IOL implantation during the secondary operation following vitrectomy can provide selected aphakic eyes with better visual recovery. (Chin J Ocul Fundus Dis, 2001,17:96-98)
Objective To explore the therapeutic value and effects of relaxing retinotomy for perforating traction retinal detachment(PTRD). Method A retrospective survey was done in 21 patinets (21 eyes) with PTRD who underwent vitrectomy combined with relaxing retinotomy in our hospital from 1998 to 2001.Results The retinae were completely reattached in all 21 cases. The visual acuity of 12 patients (57%) was counting finger, and the best visual acuity was 0.05. Among the 18 patients who were followed up for 6 to 25 months, 14(77.8%) remained retinal reattachment. Conclusions Relaxing retinotomy is effective for anatomic reattachment of PTRD, especially to the patients with retinal incarceration and severe proliferative vitreoretinopathy. (Chin J Ocul Fundus Dis，2003，19：5-7)
Objective To investigate the therapeutic effects of subconjunctival verapamil on outcome in an experimental model of traumatic proliferative vitreoretinopathy. Methods An experimental model of traumatic proliferative vitreoretinopathy was induced in pigme nt rabbits,which then were selected randomly to receive either subconjunctival verapamil injection treatment or a placebo injection(control)daily for 3 weeks.Animals were examined by indirect ophthalmoscopy at weekly intervals for 5 weeks. Eyes were enucleated for light microscopy 5 weeks later. Results Fifty-six percent(18 of 32)of the rabbits receiving subconjunctival verapamil injection had developed tractional retinal detachment,whereas eighty-one percent(26 of 32)of control animals had developed tractional retinal detachment(chi;2=4.655,P=0.031).The results of clinical examination and light microscopy didn't show evidence of toxicity between the verapamil treated animals and control animals. Conclusion Subconjunctival verapamil decreased the incidence of tractional retinal detachment due to traumatic proliferative vetreoretinopathy in this rabbit model.Verapamil at the dose used in this model has no evident toxicity on rabbit eyes.Further studies are needed to determine the doseresponse and efficacy of the drug. (Chin J Ocul Fundus Dis,1999,15:69-71)
Objective To find out about the characteristics and prognosis of retinal detachment due to ocular contusion.Methods The clinical data of 36 patients(36 eyes)with retinal detachment due to ocular contusion were retrospectively analyzed.Results There were 3 eyes(8．3％)with huge retinal hole(≥90°)，4 eyes(11．1％)oral tear of ora serrata retinae，4 eyes(11．1％)with macular hole，3 eyes(8.3％)with tractive retinal detachment，and 22 eyes(61．2％)with retinal hole(lt;90°)at other positions(including temporal peripheral hole in 9，nasal peripheral hole in 5，and posterior polar hole in 8).Proliferative vitreoretinopathy(PVR)was found in a11 patients withConclusions Retinal detachment due to ocular contusion often go with PVR．The interval from contusion to retinal detachment varies from days to months.Visual prognosis can be good when retinal detachment is diagnosed and treated in time． (Chin J Ocul Fundus Dis，2004，20：1-66)