Ophthalmodynamometry and corticosteroids in central retinal vein occlusion

Purpose : This is the first report of the monitoring of the clinical progress of a central retinal vein occlusion by measuring the retinal venous collapse pressure using ophthalmodynamometry.
Method : A 38-year-old woman with a non-ischaemic central retinal vein occlusion received systemic prednisone. The dose of prednisone was increased and decreased both abruptly and gradually. The response was monitored by weekly measurements of visual acuity, retinal appearance and retinal venous collapse pressure. The retinal appearance was assessed by comparison of repeated stereo colour photographs and fluorescein angiographs. Retinal venous collapse pressure was estimated by taking the mean of four or more ophthalmodynamometric measurements.
Results : An inverse relationship between the ophthalmodynamometric retinal venous collapse pressure and systemic prednisone dosage was observed. The visual acuity and retinal appearance remained unchanged throughout the follow-up.
Conclusions : Ophthalmodynamometry in this case was a useful method of quantitatively monitoring the response of central retinal vein occlusion to systemic prednisone. The response would not have been detected if only visual acuity and retinal appearance were used to monitor the progress.     

Retinal fascin: functional nature, subcellular distribution, and chromosomal localization

PURPOSE: To investigate the functional properties, subcellular localization, and chromosomal location of retinal fascin. METHODS: Recombinant retinal fascin protein was prepared by using a baculovirus-insect expression system. Actin-binding and -bundling assays were performed with chick actin purified from skeletal muscle. Western blot analysis and immunohistochemistry were performed with a polyclonal antibody raised against bovine retinal fascin. A human retinal cDNA library was screened with an expressed sequence tag cDNA fragment. Chromosomal location was determined with fluorescent in situ hybridization. RESULTS: The actin-binding and actin-bundling activities of retinal fascin were demonstrated by high- and low-speed centrifugation assays. Formation of filamentous (F)-actin bundles by retinal fascin in vitro was also morphologically confirmed by fluorescence microscopy and electron microscopy. Immunohistochemical analysis revealed that retinal fascin protein was localized specifically in the outer and inner segments of the photoreceptor cells in the retina. Two splicing variants of human retinal fascin cDNA were also located. One clone encoded 492 amino acids, and the other encoded 516 amino acids. The gene encoding retinal fascin was localized to human chromosome 17, region q24 -25. CONCLUSIONS: These results suggest that retinal fascin may play a role in formation of unique morphologic structures of the photoreceptor cells and is a candidate gene for retinal degenerative disorders.     

Inter-observer agreement and sensitivity of Optomap images for screening peripheral retinal lesions in patients undergoing refractive surgery

Purpose:The aim of this study was to compute the sensitivity, specificity and inter-reader variability of ultra-widefield retinal imaging (Optomap 200Tx) for screening retinal lesions before myopic refractive surgery.Methods:Two hundred and eight eyes of 109 consecutive refractive surgery candidates were included in this study. All subjects underwent Optomap 200Tx, mydriatic slit-lamp lens examination and dilated retinal examination with scleral indentation by a retinal specialist. Retinal findings by indirect dilated examination by retinal specialist was considered as the gold-standard. Sensitivity analyses for the readers were calculated between the Optomap images and the gold-standard retinal examination.Results:Seventy-three of the 208 eyes (35.1%) had peripheral retinal lesions diagnosed by the retinal specialist on dilated fundus examination. Peripheral lesions were seen on the Optomap images in 111 (53.4%) eyes. Compared to the dilated retinal examination, the detection rate with the Optomap 200Tx was 78.1% and specificity rate was 60%. The accuracy rate between the 3 readers ranged from 72% to 87%. The highest accuracy was noted with the reader post 1 year of retinal training (86.54%).Conclusion:The Optomap 200Tx showed a high sensitivity and moderate specificity for identifying peripheral retinal lesions in eyes undergoing refractive surgery. The Optomap examination is a convenient, fast and feasible method for detecting the pathological fundus changes in myopic eyes. The reliability of the examination improves when the images are interpreted by a reader with prior retinal training.     

Changes in retinal blood flow volume in experimental retinal vein compression]

The authors quantitated the retinal blood flow volume during and immediately after experimental compression of the temporal retinal vein in 5 Macaca fuscata monkey eyes. The hydrogen clearance method was used to quantitate the retinal blood flow volume. After placing a microelectrode on the retinal surface, we measured the blood flow volume 4 times at a 15-minute interval. This value served as a baseline for the experiments. Next we compressed the temporal retinal vein near the disc with a 25-gauge needle with a rounded tip under guidance by an indirect ophthalmoscope. We measured the blood flow volume during compression. The compression was maintained for 3 minutes. Further blood flow determination was performed 7 minutes after release of compression and was repeated 4 times at a 15-minute interval. During compression of the temporal retinal vein, the retinal blood flow volume in the area served by the vein decreased by an average of 35%. The flow volume recovered rapidly and remained stable after release of compression. There was no reactive hyperemia. This model appears useful to elucidate the retinal circulation of branch retinal vein occlusion.     

Ophthalmodynamometric assessment of the central retinal vein collapse pressure in eyes with retinal vein stasis or occlusion

PURPOSE: Using a new Goldmann contact lens associated ophthalmodynamometric device, it was the purpose of the present study to determine the central retinal vein collapse pressure in eyes with retinal vein occlusions or retinal venous stasis. METHODS: The prospective clinical non-interventional comparative study included 19 patients with central retinal vein occlusion ( n=8), branch retinal vein occlusion (n=4), or retinal venous stasis (n=7) and 42 subjects of a control group. With topical anesthesia, a Goldmann contact lens fitted with a pressure sensor was put onto the cornea. Pressure was exerted on the globe by pressing the contact lens, and the pressure value at the time when the central retinal vein started pulsating was noted. RESULTS: Central retinal vein collapse pressure measured 103.6+/-25.4 arbitrary units (AU) in eyes with central retinal vein occlusion what was significantly higher than in the eyes with retinal venous stasis (58.1+/-37.5 AU; p=0.02) and the eyes with branch retinal vein occlusion (43.8+/-25.5 AU; p=0.004). In the latter two groups, the measurements of the central retinal vein collapse pressure were significantly (p<0.001) higher than the measurements in the eyes of the control group (4.2+/-7.8 AU). CONCLUSION: As measured by a new ophthalmodynamometer with direct biomicroscopic visualization of the central retinal vessels during examination, central retinal vein collapse pressure is significantly higher in eyes with central retinal vein occlusion, followed by eyes with branch retinal vein occlusion, eyes with retinal venous stasis and, finally, normal eyes. These findings may have diagnostic and therapeutic implications.     

Noninvasive imaging by optical coherence tomography to monitor retinal degeneration in the mouse.

PURPOSE: Optical coherence tomography (OCT) is a high-resolution imaging technique that measures the intensity of backscattered light from biological microstructures in living tissue. The objective was to evaluate OCT as a routine, noninvasive technique for quantitative measurements of retinal thickness and detachment in small animal models of retinal degenerative diseases. METHODS: An OCT scanning unit was designed and built to visualize retinal tissue from rodents at high resolution in vivo. Several normal and retinal degeneration (rd) mouse strains with different pigmentation, as well as a transgenic mouse strain that carries a wild-type beta-PDE gene in an rd/rd background, were analyzed at different ages. Retinal detachment was induced by subretinal injection of saline. Retinal function was evaluated by full-field ERG, and then each retina was cross-sectionally scanned by OCT. OCT image analysis and measurements of retinal thickness were performed. Animals were then killed and retinal histology was documented. RESULTS: OCT images of the mouse retina revealed structural landmarks allowing assignment of retinal structures. There was no difference in the OCT pattern between pigmented and nonpigmented mice. Changes in the retinal thickness measured by OCT correlated very well with the loss in function measured by ERG and histology in rd/rd and rd/rd/tg(+) transgenic mice at a variety of ages. In addition, retinal detachment caused by surgery was easily visualized and observed by OCT imaging. CONCLUSIONS: OCT imaging is applicable to the mouse retina. There is excellent agreement between the retinal thickness measured by OCT, ERG amplitude, and retinal histology, thus validating OCT imaging as a sensitive and noninvasive tool for monitoring the structural progression of retinal diseases in rodent models. OCT also appears useful for visualizing retinal detachments in the mouse.     

裂孔源性视网膜脱离的最小量巩膜外加压手术

目的探讨裂孔源性（原发性）视网膜脱离巩膜外加压手术的最小量手术方式及其效果。方法裂孔源性视网膜脱离26例（26眼），在手术显微镜下行球结膜环形剪开、四直肌预置牵引线，在间接检眼镜下行视网膜裂孔精确定位及中度冷凝，手术显微镜下行巩膜外放液及巩膜缝线固定外加压块，所有外加压均采用修剪后的小硅胶海绵块，只固定巩膜褥式缝线1对。多发性裂孔于每个裂孔处分别于巩膜表面以1对褥式缝线固定硅胶海绵。所有手术眼均未行环扎术。手术后随访3～9月。结果所有患者手术过程顺利，无术中并发症，手术损伤小；手术后眼底检查外加压精确地顶压裂孔，视网膜完全复位25眼，1眼高度近视于手术后2周视网膜脱离复发经玻璃体手术后视网膜复位；手术后视力提高者21眼，不变4眼，下降1眼。结论最小量的外加压手术的优点是精确、可靠、创伤小，能避免传统巩膜扣带手术的一些并发症，手术成功率高。     

Detection of paravascular retinal cysts before using OCT in a highly myopic patient

Purpose We describe a case of high myopia who developed paravascular retinal rarefaction generated by vitreoretinal adhesion on retinal vessels detected using optical coherence tomography (OCT).Methods A 31-year-old man received a regular ophthalmologic examination for high myopia including detailed fundus examination and OCT.Results Detailed fundus examination revealed retinal rarefaction and fissure-like findings alongside the superior temporal retinal artery and vein in the right eye. OCT images revealed vitreoretinal adhesions on the retinal artery and a paravascular cystoid space in the inner retina. There was no retinal detachment. The axial length had increased by 1.50 mm over 15 years.Conclusion Paravascular retinal rarefaction as well as pseudohole formation caused by vitreoretinal adhesion on retinal vessels was detected in this patient using OCT. OCT might be useful to detect early-stage retinal pathologies caused by paravascular vitreoretinal traction in highly myopic patients.     

Acute Retinal Necrosis after Herpetic Encephalitis

PURPOSE: To report a case of unilateral acute retinal necrosis after herpetic encephalitis CASE REPORT: A young man was referred with a chief complaint of blurred vision and pain of the left eye 1 month after herpetic encephalitis in the left frontotemporal lobe. The patient had multiple foci of retinitis in the retinal periphery associated with vitritis, blot retinal hemorrhage and retinal arteriolitis. The impression of acute retinal necrosis was confirmed by polymerase chain reaction of aqueous humor by detecting herpes simplex virus type 2; therefore, the patient received intravenous acyclovir. CONCLUSION: Herpetic encephalitis may be a risk factor for acute retinal necrosis. The virus may reach the eye by the trans-axonal route. Prophylaxis with acyclovir may be necessary after herpetic encephalitis to prevent acute retinal necrosis.     

Endothelin-1-mediated retinal artery vasospasm and the rabbit electroretinogram.

Electroretinogram (ERG) changes invariably accompany the selective interruption of the retinal circulation that occurs in human central retinal artery occlusion. Since arteriolar ligation or ocular hypertension in the rabbit eye is occasionally used to model human central retinal artery occlusion, we conducted the present study to determine whether selective interruption of the retinal circulation of the rabbit eye alters retinal function as measured by the ERG. The vasoconstrictor, endothelin-1, was injected into the vitreous of rabbits' eyes to induce complete vasospasm and selective interruption of the retinal circulation. This procedure was compared to vascular ligation of the ophthalmic and ciliary arteries in which both the retinal and choroidal circulations were interrupted. A total of 8 rabbits was studied. Circulation was monitored angiographically in half of the eyes, and retinal function was monitored by the ERG in the remaining eyes. Endothelin-1 obliterated retinal arteriolar blood flow without affecting choroidal blood flow for at least 1 hr. Although ERG a-wave amplitude showed a small decline over 2 hr, b-wave and oscillatory potential amplitudes (measures of inner retinal function) showed no loss over this period. In contrast, ligation of the ophthalmic and ciliary arteries produced complete obliteration of both retinal arteriolar and choroidal blood flow and complete loss of the ERG after 2 min. Endothelin-1 induces acute, selective interruption of retinal arteriolar blood flow which has no significant physiologic effect on inner retinal function of the rabbit as monitored by the ERG. The avascular rabbit retina appears to be a poor choice for modeling human retinal artery occlusion.     

高度近视眼黄斑部视网膜神经上皮层厚度的分区测量研究

目的:研究高度近视眼黄斑部各区域视网膜神经上皮层厚度的分布特点,并分析其与性别、年龄、眼压、等效球镜度数和眼轴长度之间的相关性。方法:除眼底视盘旁近视弧外无其他眼部异常和眼底病变的高度近视患者102例,随机选取每例患者1眼受检。所有受检眼均予眼压、屈光检查、眼轴长度测定、9个区域的黄斑视网膜神经上皮层平均厚度和黄斑中心凹视网膜厚度最小值测定。将黄斑部各区域视网膜神经上皮层平均厚度和黄斑中心凹视网膜厚度最小值与性别、年龄、眼压、等效球镜度数及眼轴长度进行相关性分析和偏相关分析。各区黄斑视网膜神经上皮层平均厚度和黄斑中心凹视网膜厚度最小值进行多配对样本的Friedman检验。结果:本组受检者黄斑中心凹视网膜厚度最小值为175.34±29.01μm。各区黄斑视网膜神经上皮层平均厚度分布存在显著差异:内环区视网膜神经上皮层厚度较外环区厚;鼻侧和上下方视网膜神经上皮层较厚,颞侧较薄;中央区和中心小凹最薄。随着眼轴的延长,中央区视网膜神经上皮层厚度增厚,外环区上方视网膜神经上皮层变薄。结论:眼轴长度增加所致的黄斑视网膜神经上皮层厚度改变可能是高度近视黄斑变性发生发展的病理基础。     

Effects of periocular administration of triamcinolone acetonide on leukocyte-endothelium interactions in the ischemic retina

PURPOSE: Recent studies have reported that intravitreal or posterior sub-Tenon's injection of triamcinolone acetonide (TA) is effective in the treatment of macular edema resulting from retinal microcirculatory disturbances such as diabetic retinopathy and retinal vein occlusion. The effects of periocular administration of TA on leukocyte-endothelium interactions were studied after transient retinal ischemia. METHODS: Transient retinal ischemia was induced by temporary ligation of the optic nerve sheath for 60 minutes in male Long-Evans rats. After the induction of ischemia, experimental eyes received a periocular injection of TA (2 mg). In control animals, the same volume of saline was administered. Leukocyte dynamics were evaluated in the retinal microcirculation using acridine orange digital fluorography. Also, retinal thickness was studied by using optical coherence tomography and a histologic METHOD: The retinal mRNA expression of P-selectin and intercellular adhesion molecule (ICAM)-1 was semiquantitatively studied with RT-PCR. RESULTS: The leukocytes rolling along retinal vein linings increased after ischemia in the vehicle-treated rats (32.5 +/- 2.1 cells/min). No rolling leukocytes, however, were seen in the TA-treated rats. The number of accumulated leukocytes was significantly lower in the TA-treated rats (831 +/- 99 cells/mm2) than in the control (971 +/- 81 cells/mm2, P < 0.05). The treatment decreased the retinal thickness and the mRNA expression of P-selectin and ICAM-1. CONCLUSIONS: The present study demonstrated that the periocular injection of TA effectively decreased retinal thickness and inhibited leukocyte-endothelium interactions in the retina after ischemia. Downregulation of adhesion molecules of retinal vascular endothelium induced by TA may play a role in the course.     

小鼠视网膜体外电转化及Transwell体外培养的方法

目的　介绍小鼠视网膜体外电转化及体外培养的方法,并对其关键技术步骤进行探讨。方法　将新生小鼠处死后,取出眼球分离视网膜,利用电转化仪将携带绿色荧光蛋白（green fluorescent protein,GFP）报告基因的质粒转入视网膜细胞,然后在Transwell小室中铺片培养,利用免疫荧光方法检测Rhodopsin基因的表达。结果　视网膜体外培养10 d,Rhodopsin和DAPI染色显示视网膜形态完整。通过电转化方法将GFP质粒导入视网膜细胞,进行体外培养5~10 d后可检测GFP报告基因的表达。结论　视网膜体外电转化结合体外培养方法是一种快速、高效研究视网膜相关基因的方法,可以应用于视网膜疾病、视网膜发育及相关基因功能等研究,具有独特的优势。     

Risk factors for persistent epiphora following successful canalicular laceration repair

AIM:To identify the risk factors of epiphora in patients with anatomical patency after surgical repair of canalicular laceration.METHODS:This retrospective case series included 178 cases of canalicular laceration repair from 2005 to 2012.Demographic data collected from each patient included age,sex,type of injury,distance from the distal lacerated end of the canaliculus to the punctum,the severity score for the structural abnormity of the medial canthus,the duration of stent placement,and the timing of surgery.The risk factors for epiphora were evaluated using Logistic regression models.RESULTS:Among the 178 cases,45(25.3%)with lacrimal patency after irrigation had symptomatic epiphora at the final follow-up.Patients'sex,age,type of injury,duration of stent placement,timing of surgery,and concurrent trauma were not found to be significantly associated with symptomatic epiphora after surgical repair of the lacerated canaliculus(P>0.05).A distance of more than 5 mm from the distal cut end to the punctum was closely and significantly associated with symptomatic epiphora after surgical repair of the lacerated canaliculus(P<0.01).Symptomatic epiphora was significantly more frequent in patients with higher severity scores for structural abnormities of the medial canthus(P<0.01).CONCLUSION:Our results indicate that the risk factors for postoperative symptomatic epiphora include a further distance between the distal cut end and the lacrimal punctum and a higher severity score for structural abnormities of the medial canthus.These findings could be used to prognosticate postoperative symptomatic epiphora.     

Structural features of attached retina in rhegmatogenous retinal detachments

PURPOSE: To examine the thickness and structural features of the ophthalmoscopically normal-appearing, attached retina in rhegmatogenous retinal detachments by optical coherence tomography (OCT) and compare them with those of the fellow eye. METHODS: Seventy eyes of 35 patients with rhegmatogenous retinal detachments were included in this study. The retinal detachments were not total. None of the patients had pathologic myopia or a history of ocular surgery. The fellow eyes were ophthalmoscopically normal and used as controls. Attached retinal sites of the eyes with a retinal detachment and the corresponding retinal sites of the fellow eyes were examined by OCT. Three OCT sections were taken from each eye, and thicknesses of three reflective zones corresponding to the inner part of the neurosensory retina (partial neurosensory retina), photoreceptor-photoreceptor outer segment, and total retinal thickness on each OCT section were measured and compared with those of the fellow eye. These three measurements were taken as the main outcome measures and performed on five different sites of each OCT section taken from each eye. RESULTS: The mean partial neurosensory retinal thickness of the attached retina in the eyes with a retinal detachment and the corresponding retinal sites in the fellow eyes was 172.74 +/- 14.23 microm and 170.60 +/- 16.51 microm, respectively. There was no statistically significant difference between these two values. The mean photoreceptor outer segment thickness of the attached retina in the eyes with a retinal detachment and the corresponding retinal sites in the fellow eyes was 62.74 +/- 12.02 microm and 58.23 +/- 15.14 microm, respectively. There was a statistically significant difference between these two values. The mean total retinal thickness of the still-attached retina in the eyes with a retinal detachment and the corresponding retinal sites in the fellow eyes were 293.23 +/- 27.87 microm and 277.06 +/- 19.12 microm, respectively. There was a statistically significant difference between these two values. CONCLUSIONS: The main difference between the two groups of eyes was at the level of the thickness of the black hyporeflective zone, corresponding anatomically to the photoreceptor and photoreceptor outer segment that enlarges in the retinal detachments. Therefore, there may be a subclinical retinal detachment or a global retinal relaxation even in the ophthalmoscopically normal-appearing, still-attached retina. This may be the underlying cause of preoperative and postoperative signs and symptoms. Additional studies are required to confirm these findings.     

α-硫辛酸治疗大鼠视网膜缺血再灌注损伤Fas/FasL的表达与细胞凋亡的关系

目的:探讨Fas/FasL在大鼠视网膜缺血再灌注损伤(retinal ischemia reperfusion injury,RIRI)中的表达与细胞凋亡的关系及α-硫辛酸(α-LA)的治疗作用。方法:采用升高眼内压的方法建立RIRI模型,将54只SD大鼠随机分为正常组、缺血再灌注(IR)组和α-LA干预组,IR组及α-LA干预组在12,24,48,72h光镜观察视网膜内层厚度及神经节细胞丢失,TUNEL法检测视网膜神经细胞凋亡,免疫组织化学法检测视网膜组织Fas/FasL蛋白的表达。结果:IR组视网膜内层变薄,神经节细胞数目减少。细胞凋亡出现于再灌注后12h,并逐渐递增,24h达到高峰,48h开始下降。Fas/FasL表达与凋亡的神经细胞改变基本一致。α-LA干预组视网膜内层厚度和神经节细胞数目有一定恢复。凋亡细胞在12,24,48h组明显低于IR组(P<0.05);Fas表达在12,24h组较IR组显著下降(P<0.05);FasL表达在12,24,48h组较IR组明显下降(P<0.05)。结论:Fas/FasL系统参与RIRI,导致神经节细胞凋亡;α-LA可下调Fas/FasL表达,减少神经节细胞凋亡。     

Transient increased retinal hemorrhage and the retinal venous blood flow change in the course of non-ischemic central retinal vein occlusion treated with an anticoagulant

PURPOSE: To investigate transient increased retinal hemorrhage during anticoagulant therapy and changes in the retinal venous blood flow in the course of non-ischemic central retinal vein occlusion (CRVO). METHODS: Seventeen patients(eighteen eyes) with non-ischemic CRVO were studied. The retinal vein diameter, blood velocity, and blood flow were determined by the laser Doppler method in seven patients. RESULTS: The retinal hemorrhage increased in nine eyes (50%); however, the retinal hemorrhage was transient and it finally decreased without vision loss in seven of the eyes. The retinal hemorrhage increased in the other two eyes and they became ischemic. The vessel diameter decreased and both velocity and blood flow increased in six of the seven patients two weeks after the treatment. There was no significant change in blood flow in cases which showed a transient increase in retinal hemorrhage, and they did not show a decrease in vision; however, only one eye which became ischemic showed a decrease in blood flow. CONCLUSION: We can judge whether an increase in retinal hemorrhage is transient or the clinical condition is getting worse in an early stage by measuring the retinal vein blood flow quantitatively by laser Doppler flowmetry.     

Retinal vascular development and pathologic retinal angiogenesis are not impaired in matrix metalloproteinase-2 deficient mice

PURPOSE: Earlier studies have suggested a role for metalloproteinase-2 (MMP-2) in retinal angiogenesis. To investigate this further, we have studied retinal vascular development and pathologic ischemia-induced retinal angiogenesis in MMP-2-deficient and wild-type mice. METHODS: Vascular development of the retina was studied in retinal flatmounts, whereas pathologic retinal angiogenesis was analyzed in retinal flatmounts and on histologic sections using a model of ischemia-induced retinopathy. The time course of MMP-2 mRNA expression was determined by in situ hybridization and real-time polymerase chain reaction (PCR). RESULTS: Formation of the retinal vascular plexus was not significantly different in MMP-2-deficient mice as compared to wild-type mice. In ischemia-induced retinopathy, there was an increased formation of extraretinal neovascular tufts in the MMP-2-deficient mice (p < 0.05). MMP-2 mRNA expression did not correlate to either retinal vascular development or to ischemia-induced formation of extraretinal vascular tufts. CONCLUSIONS: The current data suggest that MMP-2 is not essential for either retinal vascular development or pathologic retinal neovascularization in the mouse.     

Transient ischemic injury in the rat retina caused by thrombotic occlusion-thrombolytic reperfusion

PURPOSE: To establish a clinically relevant model of transient retinal ischemia by thrombotic occlusion-thrombolytic reperfusion of the central retinal artery of the rat. METHODS: Thrombus was photochemically induced in the central retinal artery by the combination of intravenous injection of photo-sensitive dye, rose bengal, and green laser irradiation focused on the artery. Transient retinal ischemia for 60 minutes was achieved by a subsequent systemic administration of tissue-type plasminogen activator to reperfuse the occluded vessel. Samples of retinas were excised from the animals killed 3, 9, 12, 24, 48, and 78 hours after the reperfusion. The experimental data were processed using the TdT-dUTP terminal nick-end labeling (TUNEL) method to detect apoptotic cells. RESULTS: The transient retinal ischemia caused time-sequential apoptotic changes in the retinal cells as evaluated by counting the number of TUNEL-positive cells. The most remarkable changes occurred in the central area of retina, and further on the sections taken 24 hours after reperfusion. The peripheral area was less affected, and the outer nuclear cell layer was almost unaffected throughout the observation period. CONCLUSIONS: The proposed method to cause retinal transient ischemia is highly reproducible, and it is easy to simulate the progress and topographical distribution of retinal changes observed in the clinical cases of central retinal arterial occlusion and its subsequent thrombolytic reperfusion. This may provide a useful tool for constructing the effective thrombolytic strategies against the central retinal arterial occlusion and for evaluating the effects of neuroprotective agents.     

Retinal fixation of traumatic retinal detachment with metallic tacks: a case report with 10 years' follow-up

BACKGROUND: Retinal rupture and detachment caused by traumatic ocular perforation has a poor prognosis without extensive repair procedures. The authors describe the phases of treatment of a complex injury in a 21-year-old man with a traumatic retinal rupture in whom metallic tacks were used for retinal fixation. The report does not include histopathology. METHODS: Observational case report and literature review. The outcome of a 10-year follow-up is evaluated at the latest visit by determining the visual acuity (VA) and by observing the state of retina and tacks. RESULTS: A traumatic retinal rupture with detachment was treated with titanium tacks for retinal fixation. By inserting a total of 13 metallic tacks for the repair of a temporal postequatorial retinal rupture and adjacent retinal detachment a successful outcome was achieved. Two additional operations were performed to reattach the retina of nasal hemisphere in the same eye. One dislodged tack was removed at the final operation. Ten years later, at the last intervention, VA was 12/20 in the injured eye. The retina was completely attached, and the remaining 12 tacks were in place, although six of them were partially pushed up by an encircling band. Proliferative vitreoretinopathy (PVR) was absent, and a relatively narrow circumferential zone of scar tissue adjacent to the row of tacks was visible. The patient occasionally experienced glare in the affected eye, but was otherwise symptom-free. CONCLUSION: Reports of long-term experiences with mechanical retinal refixation with metallic tacks are scarce. Especially in extended use, the tacks are claimed to cause several complications, including PVR. Although modern ophthalmic surgery offers a variety of methods for retinal reattachment, the complexity of the damage caused by trauma may lead to a dead end in refixation attempts. Nevertheless, retinal tacks may represent an adjunctive remedy in complex retinal detachment cases.