Retinal function after scleral buckling for recent onset rhegmatogenous retinal detachment: assessment with electroretinography and optical coherence tomography

PURPOSE: To investigate central and peripheral retinal function after scleral buckling surgery for recent onset rhegmatogenous retinal detachment (RD). METHODS: Fifteen phakic patients with rhegmatogenous RD for <1 week underwent scleral buckling surgery. Clinical investigation, optical coherence tomography (OCT), full-field electroretinography (ERG), and multifocal ERG (mfERG) with fundus illumination were performed preoperatively and 6 months postoperatively. RESULTS: Anatomical success was achieved in 14 patients. mfERG amplitudes were reduced preoperatively in detached retina, with significant improvement at follow-up (P = 0.002). Foveal amplitudes improved significantly (P = 0.027). There was no significant difference in postoperative mfERG amplitudes between areas that had been preoperatively detached or attached (P = 0.739). In the subgroup of eight patients in whom the detachment engaged the fovea preoperatively, rod function improved significantly as assessed with full-field ERG (P = 0.008). In these patients, the extent of detachment ranged between 4 clock hours and 6 clock hours, as compared with 2 clock hours and 5 clock hours in the remaining patients. OCT showed subretinal foveal fluid in four patients at follow-up. CONCLUSIONS: In recent onset rhegmatogenous RD, total rod and localized central retinal dysfunction in detached retina can improve significantly after reattachment. mfERG and OCT are suitable tools for further studies of functional outcomes in RD.     

影响视网膜脱离患者视网膜功能的因素

目的:评价视网膜脱离患者年龄、病程、视网膜脱离面积、黄斑脱离情况等因素对视网膜功能的影响。方法:将孔源性视网膜脱离(retinal detachment,RD)188例189眼的患者年龄、病程、视网膜脱离面积、黄斑脱离情况、视力与视网膜脱离眼的fERG和mfERG各指标进行相关分析。结果:影响RD眼fERG和mfERG的主要因素是脱离面积、黄斑脱离和视力。以|γ|>0.4,且P≤0.05判定为有相关性。脱离面积与明视和暗适应最大反应ERG a、b波幅值,30Hz闪烁光幅值,OPs波数和幅值负相关;与mfERG象限野P1波幅值密度、幅值负相关。相关系数最高者为fERG暗适应最大反应b波幅值(γ=-0.704)。黄斑脱离与明视和暗适应最大反应ERG b波幅值,30Hz闪烁光ERG幅值负相关;与mfERG环形野环1的P1波幅值密度、幅值负相关,与mfERG象限野P1波幅值密度负相关,相关系数最高者为mfERG环形野环1的P1波幅值(γ=-0.584)。视力与明视和暗适应最大反应a、b波幅值,30Hz闪烁光幅值,OPs子波数和幅值正相关;与mfERG环形野环1的P1波幅值密度、幅值正相关,相关系数最高者为30Hz闪烁光ERG幅值(γ=0.597)。RD眼的fERG异常率最高者为暗适应最大反应ERG b波幅值,异常率为71.3%,视网膜脱离象限野mfERG异常率最高者为P1波幅值,异常率为85.3%。结论:影响RD患者视网膜功能的重要因素是脱离面积和黄斑脱离情况。RD眼对视网膜功能异常反应的mfERG对视网膜功能异常反应的敏感性高于fERG。     

Peeling of internal limiting membrane during vitrectomy for complicated retinal detachment prevents epimacular membrane formation

Background  To investigate the clinical benefit of internal limiting membrane (ILM) peeling at the macula for the prevention of epimacular membrane formation following vitreous surgery using silicone oil for the treatment of complicated retinal detachment. Methods  This was a non-randomized, retrospective, interventional study of a case series. Patient charts were reviewed retrospectively for 20 consecutively recruited patients who underwent successful primary vitrectomy with ILM peeling at the macula using silicone oil (group 1) and 22 consecutively recruited patients who underwent successful primary vitrectomy using silicone oil without ILM peeling at the macula for complicated rhegmatogenous retinal detachment (group 2). The main outcome measures were distant visual acuity and epimacular membrane formation. The data were analyzed and compared using Fisher’s Exact test, Pearson Chi-square test, independent t-test, Mann–Whitney U-test, and a repeated ANOVA. Results  The mean age of patients was 52.7 ± 12.6 years in group 1 and 53.2 ± 13.3 years in group 2 (p = 0.89). The mean follow-up time was 24.6 ± 7.6 weeks in group 1 and 34.1 ± 12.6 weeks in group 2 (p = 0.01). Preoperatively, ten eyes in group 1 and 10 eyes in group 2 were pseudophakic; the macula was detached in all cases. Silicone oil had been removed from all eyes of both groups at least 3 months before the final examination. There were no significant differences between the two groups with regard to sex (p = 0.44), mean duration of retinal detachment (p = 0.12), mean preoperative visual acuity (logMAR), mean number of retinal breaks (p = 0.43), and grade of proliferative vitreoretinopathy (p = 0.35). The final visual acuity (logMAR) was 0.60 ± 0.30 in group 1 and 0.72 ± 0.35 in group 2 (p = 0.49). Four eyes in group 1 and two eyes in group 2 underwent cataract surgery during silicone oil removal. Epimacular membrane formation was observed in two eyes before silicone oil removal and in four eyes within 8 weeks after silicone oil removal in group 2. No epimacular membrane formation was seen in group 1 (p = 0.02). Conclusion  ILM peeling at the macula during vitreous surgery with silicone oil for the treatment of complicated retinal detachment may prevent epimacular membrane formation without negatively affecting distant visual acuity. The results of this study were presented at the 8th Euretina Congress 2008, Vienna, Austria. The authors have no conflicting interests in the subject matter presented.     

Correlation between functional and anatomical assessments by multifocal electroretinography and optical coherence tomography in central serous chorioretinopathy

To evaluate the correlation between functional and anatomical assessments with multifocal electroretinography (mfERG) and optical coherence tomography (OCT) in patients with acute central serous chorioretinopathy (CSC). Thirty-four eyes of 34 patients with acute CSC underwent mfERG and OCT examinations. First-order mfERG N1 and P1 response amplitudes and latencies were analyzed. OCT parameters measured included central subretinal fluid (SRF) thickness, central retinal thickness, total central foveal thickness, vertical, and horizontal diameters of SRF, and macular volume. Correlation analyses were performed between best-corrected visual acuity (BCVA), mfERG parameters, and OCT measurements. Correlation analysis showed that logMAR BCVA was significantly correlated with mfERG N1 amplitudes of rings 1 and 2 (P = 0.006), N1 latency of ring 4 (P = 0.012), and P1 latency of ring 1 (P = 0.036). No significant correlation was observed between logMAR BCVA and any of the OCT measurements. For the correlation between mfERG parameters and OCT measurements, mfERG N1 and P1 latencies of the paracentral rings were significantly correlated with the central SRF thickness (P ≤ 0.024), diameters of the SRF (P ≤ 0.018), and macular volume (P ≤ 0.030). MfERG responses but not OCT measurements correlated with logMAR BCVA in patients with acute CSC. The amount of SRF nonetheless correlated with the mfERG N1 and P1 latencies of the paracentral rings, suggesting that impairment in the conduction of electrical responses in the paracentral macula is proportional to the severity of serous macular detachment in CSC. MfERG and OCT can complement each other in the functional and anatomical assessments in CSC.     

The effect of thalidomide on neovascularization in a mouse model of retinopathy of prematurity

Purpose Abnormal angiogenesis is the hallmark feature of retinopathy of prematurity (ROP), and contributes to the severe visual loss that accompanies this disease. Thalidomide is a well-known anti-angiogenic drug. We tested the assumption that injection of intraperitoneal thalidomide could reduce the severity of oxygen-induced retinopathy (OIR) in a mouse model. Methods Forty-three baby wild type mice were used in this study. The mouse model of oxygen-induced retinopathy consisted of a 5-day exposure to 75% oxygen from postnatal day 7 to 12 (P12) followed by 5 days in room air (relative hypoxia). Control mice were those with normally developing retinal vasculature exposed to room air from birth until postnatal day 17 (P17). Thalidomide (200 mg/Kg) was administered daily intraperitoneally to control and ROP mice in two protocols: (1) from P12 to P16, and (2) from P11 to P15 . Fluorescein-conjugated dextran angiography of retinal vasculature was performed on P17, and retinal whole mounts were prepared to score features of retinopathy. The parameters that were scored in a masked fashion included blood vessel growth, blood vessel tufts formation, extra retinal neovascularization, degree of central constriction, and tortuosity of vessels. These parameters constitute the Modified Retinopathy Scoring System (MRSS). In addition, quantification of the number of blood vessel tufts was performed in a masked fashion with hematoxylin & eosin (H&S) staining of paraffin-embedded eye sections. Results The retinopathy score by MRSS in the thalidomide treated mice was similar to that of untreated mice that were exposed to oxygen (9.3 ± 1.9 vs 10.15 ± 1.6; p = 0.21). The neovascularization count was also similar between the two groups (10.4 ± 5.6 vs 9.6 ± 4.8; p = 0.56). In the control group left in the room air, the retinopathy score was 0.19 ± 0.37 (p = 0) and the neovascularization count was also very low (2.92 ± 2.14; p = 0). Conclusions Although thalidomide might have a proven anti-angiogenic and anti-inflammatory effect, our model did not show a significant effect on the retinopathy. The reason might be an ineffective level of the drug in the retina due to ineffective metabolism of the drug, or due to blockage of the drug by the blood-retina barrier, or the involvement of other factors besides those influenced by thalidomide in the process. Poster presented at ISOPT, Berlin 2006.     

Regional Assessment of Cone System Function Following Uncomplicated Retinal Detachment Surgery

Purpose: To evaluate regional cone system function after uncomplicated retinal detachment (RD) surgery, by recording focal electroretinograms (FERGs) from the central and paracentral regions of the posterior pole. Methods: FERGs in response to either a central (eccentricity: 0–2.25 deg) or a paracentral annular (2.25–9 deg) uniform field, presented on a light adapting background and sinusoidally flickered at 41 Hz (95% modulation depth, 93 cd/m² mean luminance) were recorded from 16 eyes (16 patients) 2 weeks to 420 months following uncomplicated RD surgery (encircling procedure with or without scleral buckling). Pre-operatively, 10 out of 16 eyes had a macular RD. Mean time elapsed from onset of symptoms to surgery was 20 days (range: 5–90 days). Post-operatively, visual acuity ranged 0.1 to 1.0. Eight age-matched normal subjects served as controls. Amplitude and phase of the FERG fundamental harmonic were measured. Results: Compared to control eyes, affected eyes’ central and paracentral FERGs were on average reduced in amplitude (by 40% and 28%, respectively, p<0.01) and delayed in phase (by 70 and 100 degrees, respectively, p<0.01). Eyes with a macular RD did not differ in FERG amplitude or phase from eyes that had a peripheral RD. In individual affected eyes, central, but not paracentral FERG amplitudes were negatively correlated (p=0.05) with time elapsed from onset of symptoms to surgery. Conclusions: Central and paracentral cone system dysfunction may be detected even at lengthy time intervals from retinal reattachment, independent of the presence of a pre-operative macular RD. The extent of central loss appears to be inversely related to RD duration, in agreement with previous reflectometric findings on foveal cone photopigment density [Liem et al., 1994; Ophthalmology 10: 1945-51].     

Preoperative duration of retinal detachment and preoperative central retinal artery hemodynamics: repercussion on visual acuity

Purpose  To analyze if preoperative duration of primary rhegmatogenous retinal detachment (RD) influences preoperative central retinal artery (CRA) hemodynamics with repercussions on logarithmic (LogMAR) visual acuity (VA). Methods  Prospective clinical cohort study on 66 healthy patients (33 with proliferative vitreoretinopathy (PVR) and 33 with no PVR) with unilateral RD candidates for scleral buckling (SB) surgery (PVR <C3) as a first and single surgical procedure. CRA Doppler sonography parameters (peak systolic, end diastolic velocities and resistibility index) and IOP were measured before SB. Pearson’s correlations were evaluated between preoperative RD duration and each preoperative CRA parameter, and also between both variables and the LogMAR VAs (preoperative, postoperative 8 months, and the difference: postoperative 8 months minus preoperative). Results  Preoperative duration of RD was correlated (with statistical significance both PVR and no PVR) with pre- and postoperative 8 months LogMAR VAs (both positive correlations), with preoperative IOP (negative correlation), and with preoperative CRA parameters (negative correlations with CRA velocities and positive correlation with resistibility index). Preoperative CRA parameters (correlated with preoperative IOP in PVR) were correlated (negatively for CRA velocities and positively for CRA RI) with LogMAR VAs (preoperative, postoperative 8 months, and difference) in PVR. The average preoperative RD duration was longer in the PVR group than in the no PVR group (p < 0.0001). A longer preoperative RD duration was associated with macula-off in both groups. Macula-off and PVR respectively showed lower preoperative IOP and lower preoperative CRA velocities than macula-on and no PVR. Conclusions  Preoperative CRA parameters and LogMAR VAs (pre-, and postoperative 8 months) were influenced by preoperative RD duration in both no PVR and PVR. Preoperative CRA parameters were correlated with LogMAR VAs (pre-, postoperative 8 months, and the difference) only in PVR. Postoperative 8 months and preoperative LogMAR VAs were only correlated (with statistical significance) in macula-on cases of both the PVR and no PVR groups.     

One-year results of combined photodynamic therapy and intravitreal bevacizumab injection for retinal pigment epithelial detachment secondary to age-related macular degeneration

Background  To evaluate the efficacy of combined photodynamic therapy (PDT) and intravitreal bevacizumab injection in eyes with a serous pigment epithelial detachment (PED) associated with age-related macular degeneration (AMD). Methods  Twenty-two eyes with a serous PED exceeding two disc areas associated with AMD with choroidal vascular abnormalities [choroidal neovascularization (n = 10), polypoidal choroidal vasculopathy (n = 9), and retinal angiomatous proliferation (n = 3)] received combined PDT and intravitreal bevacizumab, and were followed about every 6 weeks for more than 1 year. Additional treatments were given for residual or recurrent lesions. The main outcome measures were changes in the PED height measured by optical coherence tomography, and the best-corrected visual acuity. Results  After one treatment, the PED resolved in 12 eyes (55%) and the PED decreased in ten eyes (45%). There was no recurrence in eight (36%) eyes; however, PED recurred in 14 eyes. At 1 year, the average PED height decreased to 413 microns from the baseline 751 microns (p < 0.001). Twenty eyes (91%) had improved or stabilized vision; two eyes had decreased vision due to a retinal pigment epithelial tear and subretinal hemorrhage. Conclusions  Combined PDT and intravitreal bevacizumab may decrease the PED height and stabilize visual acuity at 1 year. The authors have no proprietary and financial interest in any aspect of this report.     

30 Hz-flicker mfERG in primary open-angle glaucoma patients

Purpose This study was performed in an attempt to gain more information on whether the 30 Hz-flicker mfERG indeed provides a sensitive measure of dysfunction in patients with primary open-angle glaucoma (POAG) as has been suggested previously.Methods Eighteen POAG patients with visual field defects (MD > 2.2 dB) and glaucomatous optic neuropathies as well as 10 control subjects underwent mfERG recording as follows: 30 Hz-flicker mfERG, LED stimulus screen, 61 hexagons, L _max: 180 cd/m², L _min: 0 cd/m², recording time: ∼5 min, filter setting: 10–200 Hz. The 30 Hz response (also called the fundamental or the first harmonic response (1HW) and the second harmonic wave at 60 Hz (2HW) were analysed as an overall response and in quadrants, as well as in 4 small neighbouring areas per quadrant. The patients’ mfERGs were compared to those of the control group and to the mean defect values (MD) of the corresponding quadrants of the Octopus perimetry.Results Neither in the overall response, nor in the quadrants, nor in the smaller areas examined did amplitudes and phases of the 1HW and the 2HW or the amplitude ratio of the 2HW to the 1HW (DFT-ratio) differ from the controls (P > 0.05—ANOVA). There was no significant correlation between mfERG values and the MD (Spearman-test, Bonferroni).Conclusion Thus, the 30 Hz-flicker mfERG does not seem to be sensitive enough to separate glaucoma patients from normal.     

Effect of intravitreal plasmin on vitreous removal through a 25-gauge cutting system in the rabbit in vivo

Purpose  Intravitreal plasmin creates a posterior vitreous detachment, but may also liquefy the vitreous. This study measures the rate of vitreous removal from rabbit eyes after plasmin injection in vivo. Methods  Intravitreal injections of 150 IU hyaluronidase (n = 5), 0.5 activity units (AU, n = 6) or 0.9 AU of streptokinase-activated human plasmin (n = four groups of 6) in 0.1 ml were performed in rabbits, the fellow eyes received 0.1 ml BSS. After 30 min (hyaluronidase), 30 min, 4 h, 12 h or 24 h (0.9 AU plasmin) or 24 h (0.5 AU plasmin), 1 ml of vitreous was removed from each eye without infusion, using a 25-gauge cutter and a standardized protocol. Animals were sacrificed after surgery. Results  Compared to fellow eyes, the average rate of vitreous removal was increased by hyaluronidase by 68.9 ± 6.3% (p < 0.05) and by 0.5 AU plasmin (24 h) by 26.8 ± 3.3% (p < 0.05). 0.9 AU of plasmin increased removal rates by 0.8 ± 10% (n.s.), 15.4 ± 6.3% (p < 0.05), 40.3 ± 3.1% (p < 0.05), and 71.9 ± 32.4% (p < 0.05) after 30 min, 4 h, 12 h and 24 h incubation respectively. The ratios of removal rates of treated/control eyes in the 0.9 AU groups showed a linear correlation with incubation time (r = 0.783, p < 0.0001). Conclusion  Intravitreal plasmin increases the rate of vitreous removal in rabbits. This work was presented in part at the 76th Annual Meeting of the Association for Research in Vision and Ophthalmology, 2004. Supported in part by grants from the University of Aachen, Germany and the Deutsche Forschungsgemeinschaft (HE 3503/1-1) to M. Hermel, and by NuVue Technologies, Keene, New Hampshire, USA. W. Dailey and M. Hartzer have a proprietary interest in plasmin.     

Fundus autofluorescence findings in a mouse model of retinal detachment

Purpose. Fundus autofluorescence (fundus AF) changes were monitored in a mouse model of retinal detachment (RD). Methods. RD was induced by transscleral injection of hyaluronic acid (Healon) or sterile balanced salt solution (BSS) into the subretinal space of 4-5-day-old albino Abca4 null mutant and Abca4 wild-type mice. Images acquired by confocal scanning laser ophthalmoscopy (Spectralis HRA) were correlated with spectral domain optical coherence tomography (SD-OCT), infrared reflectance (IR), fluorescence spectroscopy, and histologic analysis. Results. In the area of detached retina, multiple hyperreflective spots in IR images corresponded to punctate areas of intense autofluorescence visible in fundus AF mode. The puncta exhibited changes in fluorescence intensity with time. SD-OCT disclosed undulations of the neural retina and hyperreflectivity of the photoreceptor layer that likely corresponded to histologically visible photoreceptor cell rosettes. Fluorescence emission spectra generated using flat-mounted retina, and 488 and 561 nm excitation, were similar to that of RPE lipofuscin. With increased excitation wavelength, the emission maximum shifted towards longer wavelengths, a characteristic typical of fundus autofluorescence. Conclusions. In detached retinas, hyper-autofluorescent spots appeared to originate from photoreceptor outer segments that were arranged within retinal folds and rosettes. Consistent with this interpretation is the finding that the autofluorescence was spectroscopically similar to the bisretinoids that constitute RPE lipofuscin. Under the conditions of a RD, abnormal autofluorescence may arise from excessive production of bisretinoid by impaired photoreceptor cells.     

Bevacizumab (Avastin) treatment in patients with retinal angiomatous proliferation

Aim To determine the anatomical and functional outcome after injection of bevacizumab (Avastin, Genentech) in eyes with retinal angiomatous proliferation (RAP). Design Prospective interventional case series. Methods Sixteen eyes of 16 consecutive patients with visual loss due to RAP underwent intravitreal injections of 1.25 mg (0.05 ml) bevacizumab. Best corrected visual acuity testing, fluorescein and ICG-angiography as well as OCT imaging were performed at baseline and at each follow-up visit within a 3-month period. Results Mean visual acuity pre-injection was 0.68 ± 0.36 logMAR (n = 16), mean reading ability 0.58 ± 0.26 logRAD (n = 11). Far vision increased significantly by a mean of 1.7 ± 2 lines 4 weeks after the injection (p = 0.004), as did reading (0.6 ± 2.3 lines, p > 0.05). Both remained stable up to 3 months. Central retinal thickness decreased from 367 ± 112 μm (mean±SD) to 272 ± 123 μm 3 months after injection (p = 0.006). Leakage decreased angiographically in 12 eyes (75%) and remained stable in four eyes (25%). Re-injection of bevacizumab within the 3-month follow-up period was performed once in eight eyes, and twice in one eye. No adverse events were observed. Conclusion Intravitreal bevacizumab (Avastin) resulted in a reduction of leakage, intra- and subretinal fluid. An increase in visual acuity was seen already 4 weeks after first injection. However, a complete occlusion of feeder vessels could not be achieved within this 3-month period. Randomized clinical trials would be required to evaluate dose and frequency of injections and possible beneficial effects of combination therapies, as well as the long-term results.     

Functional implications of short‐term retinal detachment in porcine eyes: study by multifocal electroretinography

Purpose: The aim of the study was to determine the type and magnitude of detectable changes in pig multifocal electroretinography (mfERG) induced by the vitreoretinal surgical procedures necessary to gain access to the subretinal space. Methods: Twenty pigs underwent posterior segment surgery. Six animals had a vitrectomy (V), six had in addition a retinal bleb detachment (V + B); five had in addition a retinal diathermia on the bleb (V + B + D) and three received a retinotomy in the diathermized retinal area (V + B + D + R). mfERG evaluation was performed at baseline and 1 and 6 weeks postoperatively. Selected eyes were enucleated for histological evaluation. Results: The retinal detachments blebs all reattached spontaneously. All four surgical sequences resulted in slight, non‐significant changes in the mfERG peaks. A trend towards an amplitude reduction of the mfERG peaks N1, P1 and N2 were observed within the first postoperative week. After 6 weeks, all amplitudes had normalized. Of the implicit times only that of peak N1 (after retinal diathermia) was prolonged significantly at 1 week (P = 0.037). However, it returned to the preoperative level after 6 weeks. Histologically, the retinal detachment bleb was characterized by transient double layering of the retinal pigment epithelium (RPE) and loss photoreceptor outer segments. Conclusion: Access to the subretinal space in pigs can be gained without permanent detectable changes in the mfERG. A short‐term retinal detachment was found to cause only reversible electrophysiological and histological changes in the outer retina, which suggests that this procedure is tolerated well in the porcine retina. The size of the known destructive lesion (retinotomy) was too small to be detected, given the spatial resolution of the mfERG method applied. In the future, the presented protocol can be used to assess the functional outcome of surgery and transplantation in the subretinal space in pigs.     

复杂性视网膜脱离的多焦视网膜电图研究

目的 探讨多焦视网膜电图（mfERG）对复杂性视网膜脱离（RD）视功能客观评价的意义。方法 应用VERIS ScienceTM 4．2mfERG检测仪对80例复杂性RD患者的双眼进行检测,并与正常对照组比较。结果 复杂性RD患者的对侧眼、患眼在6个环的N1波、P1波振幅密度较正常对照组降低,潜时延长,差异均有统计学意义（P〈0．01）。有严重玻璃体积血组的N1、P1波振幅密度在2～6环高于无严重玻璃体积血组,差异均有统计学意义（P〈0．05）。重度PVR组的N1、P1波振幅密度低于轻度PVR组,在6个环差异均有统计学意义（P〈0．05）。黄斑裂孔组在所有6个环的N1、P1波振幅密度较正常对照组降低,潜时延长,差异均有统计学意义（P〈0．01）。结论 mfERG能客观定量评价复杂性RD患者的视功能。严重的玻璃体积血、黄斑裂孔、PVR对视功能有明显影响。     

Uveal and capsular biocompatibility of two foldable acrylic intraocular lenses in patients with endogenous uveitis — a prospective randomized study

Background  To compare a hydrophobic and a hydrophilic acrylic single-piece intraocular lens (IOL) in uveitis patients with respect to biocompatibility and visual outcome. Methods  Prospective, randomized study in patients with noninfectious uveitis after phacoemulsification and implantation of either a hydrophobic AcrySof™ (group 1, n = 30) or a hydrophilic Akreos adapt™ (group 2, n = 30), sharp-edged acrylic IOL. The primary outcome was uveal biocompatibility, detected by giant-cell deposition, anterior chamber cell count and laserflare photometry over a 6-month follow-up period. Secondary outcome measures were capsular biocompatibility, as detected by posterior capsule opacification (PCO), lens epithelial cell outgrowth and Nd:YAG capsulotomies, and visual outcome. Results  The groups did not differ with respect to anatomic type of uveitis, immunosuppressive treatment, associated systemic disease, and intraoperative manipulation. The number of giant cells on the anterior IOL surface was higher in group 1 than in group 2 (p = 0.03). The number of anterior chamber cells, laser flare photometry levels, and uveitis reactivations after surgery did not differ between the groups. After 6 months, the number of patients with PCO development (p = 1.0) and Nd:YAG capsulotomies (p = 0.21), lens epithelial cell outgrowth, visual outcome and uveitis complications were comparable in both groups. Conclusions  Both of the acrylic IOLs used had good uveal and capsular biocompatibility, leading to significant improvement in BCVA in patients with noninfectious uveitis. No obvious differences were detected at 6 months with respect to uveal and capsular biocompatibility and visual outcome. The authors have no financial interest in any of the materials used in this study.     

Visual fixation development in children

Background The ability to keep steady fixation on a target is one of several aspects of good visual function. However, there are few reports on visual fixation during childhood in healthy children. Methods An infrared eye-tracking device (Orbit) was used to analyse binocular fixation behaviour in 135 non-clinical participants aged 4–15 years. The children wore goggles and their heads were restrained using a chin and forehead rest, while binocularly fixating a stationary target for 20 s. Results The density of fixations around the centre of gravity increased with increasing age (p < 0.01), and the time of fixation without intruding movements increased with increasing age (p = 0.02), while intruding saccades decreased with increasing age (p < 0.01). The number of blinks and drifts did not differ between 4 and 15 years, and there were no significant differences with regard to gender or laterality in any of the investigated variables. No nystagmus was observed. Conclusion This study establishes values for visual fixation behaviour in a non-clinical population aged 4–15 years, which can be used for identifying children with fixation abnormalities.     

Glial cell reactivity in a porcine model of retinal detachment

PURPOSE: Detachment of the neural retina from the pigment epithelium causes, in addition to photoreceptor deconstruction and neuronal cell remodeling, an activation of glial cells. It has been suggested that gliosis contributes to the impaired recovery of vision after reattachment surgery that may involve both formerly detached and nondetached retinal areas. Müller and microglial cell reactivity was monitored in a porcine model of rhegmatogenous retinal detachment, to determine whether gliosis is present in detached and nondetached retinal areas. METHODS: Local detachment was created in the eyes of adult pigs by subretinal application of hyaluronate. Retinal slices were immunostained against glial intermediate filaments and K+ and water channel proteins (aquaporin-4, Kir4.1, Kir2.1), and P2Y receptor proteins. In retinal wholemounts, adenosine 5'-triphosphate (ATP)-induced intracellular Ca2+ responses of Müller cells were recorded, and microglial and immune cells were labeled with Griffonia simplicifolia agglutinin isolectin I-B4. K+ currents were recorded from isolated Müller cells. RESULTS: At 3 and 7 days after surgery, Müller cells in detached retinas showed a pronounced gliosis, as revealed by the increased expression of the intermediate filaments glial fibrillary acidic protein and vimentin, by the decrease of Kir4.1 immunoreactivity and of the whole-cell K+ currents, and by the increased incidence of cells that showed Ca2+ responses on stimulation of purinergic (P)2 receptors by ATP. By contrast, the immunohistochemical expression of Kir2.1 and aquaporin-4 were not altered after detachment. The increase in the expression of intermediate filaments, the decrease of the whole-cell K+ currents and of the Kir4.1 immunolabeling, and the increase in the Ca2+ responsiveness of Müller cells were also observed in attached retinal areas surrounding the focal detachment. The density of microglial-immune cells at the inner surface of the retinas increased in both detached and nondetached retinal areas. The immunoreactivities for P2Y1 and P2Y2 receptor proteins apparently increased only in detached areas. CONCLUSIONS: Reactive responses of Müller and microglial cells are not restricted to detached retinal areas but are also observed in nondetached regions of the porcine retina. The gliosis in the nondetached retina may reflect, or may contribute to, neuronal degeneration that may explain the impaired recovery of vision observed in human subjects after retinal reattachment surgery.     

Visual Field and Multifocal Electroretinography and their Correlations in Patients on Hydroxychloroquine Therapy

Purpose To evaluate the effects of hydroxychloroquine on visual field and multifocal electroretinography (mfERG) and their correlations in patients taking hydroxychloroquine.Methods This was a cross-sectional study in which patients on hydroxychloroquine therapy underwent automated 10-2 threshold static visual field examination and mfERG recordings. Non-parametric unadjusted and age-adjusted Spearman correlation coefficients ρ were calculated between the cumulative dose of hydroxychloroquine and the visual field mean deviation (MD) and pattern standard deviation (PSD) values; and the mfERG response amplitudes and peak latencies. Correlation analysis was also performed between the visual field MD and PSD values and the mfERG response amplitudes and peak latencies.Results A total of 26 eyes in 13 patients were analyzed. The mean duration of hydroxychloroquine therapy was 4.9 years and the mean cumulative dose was 574 g. No significant correlation was found between the cumulative dose of hydroxychloroquine and the visual field MD and PSD values. There were significant correlations between the cumulative dose of hydroxychloroquine and mfERG N1 and P1 response amplitudes for the central rings (ring 1–3). The correlations between the dose of hydroxychloroquine and mfERG N1 and P1 response amplitudes were strongest for the paracentral ring 2 (ρ =−0.63 and ρ =−0.62, respectively, P = 0.001). Significant correlations were also found between the visual field MD values and mfERG response amplitudes of various ring eccentricities.Conclusions In patients on hydroxychloroquine, mfERG response amplitude correlated with both the 10-2 visual field MD values and with the cumulative dose of hydroxychloroquine used. The use of mfERG can provide objective measurement of retinal function in patients on hydroxychloroquine and may provide supplementary quantitative information to visual field findings.     

Circulatory parameters in the retrobulbar central retinal artery and vein of patients with diabetes and medically treated systemic hypertension

Background  We aim to study the circulatory parameters in the retrobulbar central retinal artery and vein in diabetic patients with and without medically treated systemic hypertension. Methods  The study included 108 patients with diabetes that were allocated in four different groups according to the presence of diabetic retinopathy (DR) and hypertension: group 1—patients without DR and without hypertension (n = 23), group 2—patients without DR and with hypertension (n = 21), group 3—patients with nonproliferative DR and without hypertension (n = 36), group 4—patients with nonproliferative DR and with hypertension (n = 28). The circulatory parameters that were evaluated were: peak systolic blood velocity (PSV), end-diastolic blood velocity (EDV), maximum venous velocity (Vmax), minimum venous velocity (Vmin) and the Pourcelot index which were measured using color Doppler imaging. Non-parametric tests were used to test inter-group differences. Spearman’s coefficient of correlation was tested between ocular perfusion pressure and the circulatory parameters in each of the patient groups. Contingency table was performed to test the relation of diabetic retinopathy and hypertension to the PSV in the central retinal artery. Results  The PSV and EDV in the central retinal artery was significantly higher in group 1 (p = 0.02, p = 0.04) and group 2 (p = 0.02, p = 0.02) than in group 3. The Pourcelot index in the central retinal vein was significantly lower in group 1 than in group 4 (p = 0.02), and in group 2 than in groups 3 and 4 (p = 0.02, p < 0.01). A significant relationship was detected between the presence of hypertension, the stage of diabetic retinopathy and the PSV in the central retinal artery of our patients (χ² = 8.29; p = 0.04). Conclusion  Medically treated hypertension affects the retrobulbar circulatory parameters in the central retinal artery and vein in diabetes.     

Preoperative B-scan ultrasonography of the vitreoretinal interface in phakic patients undergoing rhegmatogenous retinal detachment repair and its prognostic significance

Purpose To perform ultrasonographic evaluation of the preoperative status of the posterior vitreoretinal interface in phakic patients undergoing surgery for retinal detachment (RD) with flap tear(s) and to investigate its relationship with postoperative anatomic and visual acuity outcomes. Methods A prospective, consecutive case series including 50 phakic eyes of 49 patients with retinal detachment and flap tear(s) undergoing retinal detachment surgery by a single vitreoretinal surgeon, who was unaware of the patient’s preoperative B-scan ultrasonographic findings. Main outcome measures were comparisons between patients with partial versus complete posterior vitreous detachment (PVD) of primary retinal reattachment rates (retinal reattachment with a single surgical procedure), rates of retinal reattachment at month 12, and visual acuity outcomes at month 12. Results Partial PVD was observed in 22 (44%) eyes and complete PVD in 28 (56%) eyes. Eighteen eyes underwent pneumatic retinopexy, 15 underwent scleral buckling, and 17 underwent pars plana vitrectomy. Retinal reattachment with a single surgical procedure was achieved in 76% (38/50) of eyes, including 54.5% (12/22) of eyes with partial PVD at baseline and 92.9% (26/28) of eyes with complete PVD at baseline (P < 0.01). Stratification by type of surgical intervention demonstrated a significantly higher rate of primary anatomic success for pneumatic retinopexy among patients with complete PVD compared to partial PVD (P = 0.02). Retinal reattachment at month 12 was achieved in 100% (50/50) of eyes. At last follow-up, the mean (±SD) number of interventions was 1.70 (±1.10) for patients with partial PVD at baseline and 1.10 (±0.30) for patients with complete PVD (P < 0.01). There was no significant difference among the groups in mean change in visual acuity from baseline to month 12, nor in the distribution of visual acuities at month 12. Conclusions In phakic patients with retinal detachment and flap tear(s), a higher primary anatomic success rate may be associated with the presence of a complete PVD compared to a partial PVD. Subgroup analysis suggests that the presence of partial PVD at baseline might influence negatively the primary anatomic success rate, particularly for eyes undergoing pneumatic retinopexy. Presented in part as a paper at the ARVO 2004 Annual Meeting, Fort Lauderdale, FL, and at the American Society of Retina Specialists 2004 Annual Meeting, San Diego, CA. The authors have full access to all the data in the study and agree to allow Graefe’s Archive for Clinical and Experimental Ophthalmology to review our data upon request. Financial interest: F. Rezende, none; M. Kapusta, none; R. Costa, none; I. Scott, none. An erratum to this article can be found at