A COVID-19-Related Retinopathy Case Report.

The recent outbreak of the severe acute respiratory syndrome coronavirus-2 has been declared a worldwide pandemic by the WHO. Within various multi-organ involvements, several ocular manifestations have been described. We report the case of a patient diagnosed with COVID-19 who presented with a progressive increase of bilateral cotton wool spots over a 1-week period, despite quick and complete recovery of systemic signs of the disease and no ocular symptoms. We followed the evolution of such lesions over a 3-month period. Here, we underline the importance of retinal screening even if no ocular symptom is reported. Furthermore, we demonstrate the essential role of fundus examination as a reflection of systemic vascular changes.

Taurine treatment of retinal degeneration and cardiomyopathy in a consanguineous family with SLC6A6 taurine transporter deficiency.

In a consanguineous Pakistani family with two affected individuals, a homozygous variant Gly399Val in the eighth transmembrane domain of the taurine transporter SLC6A6 was identified resulting in a hypomorph transporting capacity of ~15% compared with normal. Three-dimensional modeling of this variant has indicated that it likely causes displacement of the Tyr138 (TM3) side chain, important for transport of taurine. The affected individuals presented with rapidly progressive childhood retinal degeneration, cardiomyopathy and almost undetectable plasma taurine levels. Oral taurine supplementation of 100 mg/kg/day resulted in maintenance of normal blood taurine levels. Following approval by the ethics committee, a long-term supplementation treatment was introduced. Remarkably, after 24-months, the cardiomyopathy was corrected in both affected siblings, and in the 6-years-old, the retinal degeneration was arrested, and the vision was clinically improved. Similar therapeutic approaches could be employed in Mendelian phenotypes caused by the dysfunction of the hundreds of other molecular transporters.

Bi-allelic Loss-of-Function Variants in DNMBP Cause Infantile Cataracts.

Infantile and childhood-onset cataracts form a heterogeneous group of disorders; among the many genetic causes, numerous pathogenic variants in additional genes associated with autosomal-recessive infantile cataracts remain to be discovered. We identified three consanguineous families affected by bilateral infantile cataracts. Using exome sequencing, we found homozygous loss-of-function variants in DNMBP: nonsense variant c.811C>T (p.Arg271∗) in large family F385 (nine affected individuals; LOD score = 5.18 at θ = 0), frameshift deletion c.2947_2948del (p.Asp983∗) in family F372 (two affected individuals), and frameshift variant c.2852_2855del (p.Thr951Metfs∗41) in family F3 (one affected individual). The phenotypes of all affected individuals include infantile-onset cataracts. RNAi-mediated knockdown of the Drosophila ortholog still life (sif), enriched in lens-secreting cells, affects the development of these cells as well as the localization of E-cadherin, alters the distribution of septate junctions in adjacent cone cells, and leads to a ∼50% reduction in electroretinography amplitudes in young flies. DNMBP regulates the shape of tight junctions, which correspond to the septate junctions in invertebrates, as well as the assembly pattern of E-cadherin in human epithelial cells. E-cadherin has an important role in lens vesicle separation and lens epithelial cell survival in humans. We therefore conclude that DNMBP loss-of-function variants cause infantile-onset cataracts in humans.

JNK Inhibition Reduced Retinal Ganglion Cell Death after Ischemia/Reperfusion In Vivo and after Hypoxia In Vitro.

Mitogen-activated protein kinases (MAPKs) are key regulators that have been linked to cell survival and death. Among the main classes of MAPKs, c-jun N-terminal kinase (JNK) has been shown to mediate cell stress responses associated with apoptosis. In Vitro, hypoxia induced a significant increase in 661W cell death that paralleled increased activity of JNK and c-jun. 661W cells cultured in presence of the inhibitor of JNK (D-JNKi) were less sensitive to hypoxia-induced cell death. In vivo, elevation in intraocular pressure (IOP) in the rat promoted cell death that correlated with modulation of JNK activation. In vivo inhibition of JNK activation with D-JNKi resulted in a significant and sustained decrease in apoptosis in the ganglion cell layer, the inner nuclear layer and the photoreceptor layer. These results highlight the protective effect of D-JNKi in ischemia/reperfusion induced cell death of the retina.

Development of an intravitreal peptide (BQ123) sustained release system based on poly(2-hydroxyoctanoic acid) aiming at a retinal vasodilator response.

PURPOSE: Development of a novel formulation for intravitreal administration, in which the endothelinA receptor antagonist BQ123 is incorporated in a biodegradable and injectable polymer drug delivery system, poly(2-hydroxyoctanoic acid), aiming at a prolonged retinal vasodilator response. METHODS: BQ123 was incorporated in poly(2-hydroxyoctanoic acid), leading to an easily injectable, homogenous mixture. In vitro release profiles were obtained in porcine vitreous humor (n=6). The ex vivo biocompatibility was studied by placing the formulation in contact with porcine retinal tissues and performing histology. In a pilot in vivo study, the change in retinal vessel diameter of mini pigs (n=2) was followed over 3 h after an intravitreal injection of the formulation, as well as the release of BQ123 from the polymer system for approximately 7 days (n=6). RESULTS: In vitro, a constant release profile was obtained, releasing approximately 91% of BQ123 within 7 days. Histology on the porcine retinal tissues showed good ex vivo biocompatibility. In vivo, a vasodilative response was observed, with a retinal vessel diameter increase from 14% after 15 min, for approximately 39% after 3 h. At t=3 h, the BQ123 concentration in the vitreous humor was 0.7±0.2 µg/mL, followed by 1.5±1.0 and 1.1±0.8 µg/mL after 3 and 7 days, respectively. 39.9%±6.0% of BQ123 was still present in the polymer depot at t=7 days. CONCLUSIONS: The results show that an intravitreal injection of this drug delivery system leads to a prolonged vasodilative response and a BQ123 release over 7 days, suggesting its therapeutic potential in the management of retinal ischemic conditions.

Autophagy induction does not protect retina against apoptosis in ischemia/reperfusion model.

The role played by autophagy after ischemia/reperfusion (I/R) in the retina remains unknown. Our study investigated whether ischemic injury in the retina, which causes an energy crisis, would induce autophagy. Retinal ischemia was induced by elevation of the intraocular pressure and modulation of autophagic markers was analyzed at the protein levels in an early and late phase of recovery. Following retinal ischemia an increase in LC3BII was first observed in the early phase of recovery but did not stay until the late phase of recovery. Post-ischemic induction of autophagy by intravitreal rapamycin administration did not provide protection against the lesion induced by the ischemic stress. On the contrary, an increase in the number of apoptotic cells was observed following I/R in the rapamycin treated retinas.

Safety of 20-gauge transconjunctival sutureless vitrectomy.

PURPOSE: To study the safety of 20-gauge transconjunctival sutureless vitrectomy. METHODS: Clinical data of patients who underwent 20-gauge transconjunctival sutureless vitrectomy for the first time, for various disorders, were reviewed retrospectively. The main outcome measures were the number of sclerotomies requiring suturing as well as the intra- and postoperative complications. RESULTS: A total of 179 operations were performed. Indications for vitrectomy included 68 idiopathic epiretinal membranes, 26 macular holes, 23 phakic and 16 pseudophakic retinal detachments, and 46 various other, less common etiologies. Of these 179 operations, 166 (93%) were sutureless. Of the 537 sclerotomies created, 25 (5%) received a single transconjunctival-scleral suture. Intraoperative complications included premature dislodging of the cannulas in 2 sclerotomies and an iatrogenic horseshoe tear at 1 sclerotomy site. Postoperative complications comprised transient hypotony in 14 cases, subconjunctival gas in 2 cases, and choroidal effusion in 1 case. No serious complications (such as endophthalmitis) were observed. CONCLUSION: 20-gauge transconjunctival sutureless vitrectomy can be considered safe, as the intra- and postoperative complications observed are neither numerous nor significant. Sclerotomies appear to be safe and relatively easy to perform, without compromising the advantages of sutureless surgery.

Long-term results of the effect of intravitreal ranibizumab on the retinal arteriolar diameter in patients with neovascular age-related macular degeneration.

PURPOSE: To study the effect of intravitreal (IVT) ranibizumab on the retinal arteriolar diameter in patients with neovascular age-related macular degeneration (AMD). METHODS: Ten eyes of 10 patients with previously untreated neovascular AMD were included. All eyes had three monthly IVT injections of ranibizumab and then were retreated as needed, based on visual acuity and optical coherence tomography (OCT) criteria. The diameter of the retinal arterioles was measured in vivo with a retinal vessel analyser (RVA) before the first IVT injection, 7 and 30 days after the first, the second and the third injection, and at month 12 of follow-up. RESULTS: A significant vasoconstriction of the retinal arterioles was observed following each one of the first three IVT injections of ranibizumab. Thirty days following the first, second and third injection, there was a mean decrease of 8.4 ± 3.2%, 11.9 ± 4.5% and 18.5 ± 7.2%, respectively, of the retinal arteriolar diameter compared with baseline (p < 0.01). At month 12, the vasoconstriction was still present with a mean decrease of 19.1 ± 8.3% of the retinal arteriolar diameter compared with baseline (p < 0.01). Median number of ranibizumab injections was 4 (range 3-10). There was no correlation between the number of injections and percentage diameter decrease at month 12 (r = -0.54, p > 0.1). There was no significant change in mean arterial pressure (MAP) during the period of follow-up (p > 0.05). CONCLUSIONS: These results suggest that IVT ranibizumab induces sustained retinal arteriolar vasoconstriction in eyes with neovascular AMD.

Design and in vitro assessment of L-lactic acid-based copolymers as prodrug and carrier for intravitreal sustained L-lactate release to reverse retinal arteriolar occlusions.

Ophthalmic conditions in which the retinal vasculature is obstructed generally lead to vision loss. Administration of the vasodilator L-lactate might offer a treatment strategy by restoring the blood flow, but unfortunately its effect after single intravitreal injection is short-lived. This study describes a concept in which the sustained release of L-lactic acid from a biodegradable copolymer system is investigated. The 50:50 (n/n) copolymer system, composed of L-lactic acid and L,D-2-hydroxyoctanoic acid, is a viscous injectable that will form an intravitreal drug depot. Hydrolysis of the copolymer will automatically lead to the release of L-lactic acid, which will convert to L-lactate at physiological pH, thereby providing a carrier and pro-drug in one. In vitro and ex vivo release studies demonstrate an L-lactic acid release over several weeks. Biocompatibility of the co-polymer and its degradation products is shown on a human retinal pigment epithelial cell line and on ex vivo retinal tissues. A low molecular weight copolymer (1200 g/mol) with low polydispersity has promising properties with a constant release profile, good biocompatibility and injectability.

Preretinal partial pressure of oxygen gradients before and after experimental pars plana vitrectomy.

PURPOSE: To evaluate preretinal partial pressure of oxygen (PO2) gradients before and after experimental pars plana vitrectomy. METHODS: Arteriolar, venous, and intervascular preretinal PO2 gradients were recorded in 7 minipigs during slow withdrawal of oxygen-sensitive microelectrodes (10-µm tip diameter) from the vitreoretinal interface to 2 mm into the vitreous cavity. Recordings were repeated after pars plana vitrectomy and balanced salt solution (BSS) intraocular perfusion. RESULTS: Arteriolar, venous, and intervascular preretinal PO2 at the vitreoretinal interface were 62.3 ± 13.8, 22.5 ± 3.3, and 17.0 ± 7.5 mmHg, respectively, before vitrectomy; 97.7 ± 19.9, 40.0 ± 21.9, and 56.3 ± 28.4 mmHg, respectively, immediately after vitrectomy; and 59.0 ± 27.4, 25.2 ± 3.0, and 21.5 ± 4.5 mmHg, respectively, 2½ hours after interruption of BSS perfusion. PO2 2 mm from the vitreoretinal interface was 28.4 ± 3.6 mmHg before vitrectomy; 151.8 ± 4.5 mmHg immediately after vitrectomy; and 34.8 ± 4.1 mmHg 2½ hours after interruption of BSS perfusion. PO2 gradients were still present after vitrectomy, with the same patterns as before vitrectomy. CONCLUSION: Preretinal PO2 gradients are not eliminated after pars plana vitrectomy. During BSS perfusion, vitreous cavity PO2 is very high. Interruption of BSS perfusion evokes progressive equilibration of vitreous cavity PO2 with concomitant progressive return of preretinal PO2 gradients to their previtrectomy patterns. This indicates that preretinal diffusion of oxygen is not altered after vitrectomy. The beneficial effect of vitrectomy in ischemic retinal diseases or macular edema may be related to other mechanisms, such as increased oxygen convection currents or removal of growth factors and cytokines secreted in the vitreous.

Retinal blood flow evaluation.

Much of our basic knowledge of retinal blood flow regulation is based on data obtained from animal experiments through the use of invasive techniques. However, during the last decades, major developments in the field of optics and lasers have led to a variety of noninvasive techniques, which have been applied to the human eye for the investigation of retinal hemodynamics, and more specifically the regulation of retinal blood flow in response to a number of physiological and pharmacological stimuli. The Retinal Vessel Analyzer has markedly simplified the measurement of the diameter of retinal vessels, as well as the change in this diameter evoked by various physiological stimuli (dynamic measurements). Bidirectional laser Doppler velocimetry allows the measurement of absolute red blood cell centerline velocity, which, when combined with the diameter allows the calculation of retinal blood flow in the main retinal vessels. Laser Doppler flowmetry and laser speckle flowgraphy are techniques that measure the velocities of blood in discrete areas of the retinal tissue microcirculation. Adding a scanning capability, a spatial map of velocities across the retinal tissue is obtained. The blue-field simulation technique allows the quantification of the velocity, number and velocity pulsatility of leukocytes moving in the retinal capillaries of the macular region. With color Doppler imaging, the peak systolic and end-diastolic values of blood velocity in the ophthalmic and central retinal artery are measured, from which a resistivity index is obtained. These techniques may help better understand the role of altered retinal blood flow and its regulation in the pathogenesis of retinal diseases of vascular origin.

The rationale of retinal endovascular fibrinolysis in the treatment of retinal vein occlusion: from experimental data to clinical application.

PURPOSE: We describe a retinal endovascular fibrinolysis technique to directly reperfuse experimentally occluded retinal veins using a simple micropipette. METHODS: Retinal vein occlusion was photochemically induced in 12 eyes of 12 minipigs: after intravenous injection of 10% fluorescein (1-mL bolus), the targeted retinal vein segment was exposed to thrombin (50 units) and to Argon laser (100-200 mW) through a pars plana approach. A beveled micropipette with a 30-µm-diameter sharp edge was used for micropuncture of the occluded vein and endovascular microinjection of tissue plasminogen activator (50 µg/mL) in 11 eyes. In one control eye, balanced salt solution was injected. The lesion site was examined histologically. RESULTS: Retinal vein occlusion was achieved in all cases. Endovascular microinjection of tissue plasminogen activator or balanced salt solution led to reperfusion of the occluded retinal vein in all cases. Indicative of successful reperfusion were the following: continuous endovascular flow, unaffected collateral circulation, no optic disk ischemia, and no venous wall bleeding. However, balanced salt solution injection was accompanied by thrombus formation at the punctured site, whereas no thrombus was observed with tissue plasminogen activator injection. CONCLUSION: Retinal endovascular fibrinolysis constitutes an efficient method of micropuncture and reperfusion of an experimentally occluded retinal vein. Thrombus formation at the punctured site can be prevented by injection of tissue plasminogen activator.

Retinal vessel diameter can reliably be determined in minipigs using Retinal Vessel Analyser with a microscope-mounted fundus camera.

PURPOSE: Retinal Vessel Analyser (RVA) is a validated instrument to measure retinal vessel diameter in humans. The purpose of this study was to assess the reproducibility (inter-observer reliability) and the repeatability (test-retest reliability) of RVA with a microscope-mounted fundus camera to determine retinal vessel diameter in minipigs. METHODS: Ocular fundus image from five anaesthetized minipigs was recorded in a digital videotape for approximately 5 min, under stable systemic arterial pressure and gas conditions. To evaluate the reproducibility, each one of two investigators used RVA to measure the diameter of the superior temporal retinal artery on five separate 30-second video sequences from each minipig, which were the same video sequences for both investigators. To evaluate the repeatability, one investigator performed five measurements on a single, randomly selected, 30-second video sequence from each minipig. The reproducibility was determined using the intra-class correlation coefficient (ICC), and the repeatability was assessed using the coefficient of variation (COV). Bland-Altman plots were also used to assess agreement between the two investigators. RESULTS: Retinal arteriolar diameter measurements with RVA in minipigs were highly reproducible. Differences between the two investigators were lower than 0.7%. The ICC was 1.00, indicating perfect reproducibility, and the mean COV was 0.18%, reflecting excellent repeatability of the measurements with RVA. CONCLUSION: Retinal vessel diameter can reliably be determined not only in humans, but also in minipigs, using the commercially available RVA apparatus and a microscope-mounted fundus camera.

Vision impairment during cardiac surgery and extracorporeal circulation: current understanding and the need for further investigation.

The aim of this article was to provide a comprehensive review of current knowledge regarding ocular hemodynamic alterations affecting the retinal neuroglial cells and optic nerve head (ONH) function during cardiac surgery. Literature indicates that visual loss after heart surgery is a rare but devastating complication provoked by two main causes of optic ischaemia and infarction during on-pump cardiac procedures: microembolism and/or hypoperfusion. Retinal ischaemia and ischaemic optic neuropathy are two possible major consequences of extracorporeal circulation in cardiac surgery. The hemodynamic modifications within the vascular beds of retina and ONH during cardiovascular operations have been incompletely studied. Consequently, it is of great interest to investigate the hemodynamic changes during cardiopulmonary bypass within the choroidal, retinal and optic nerve microcirculations as well as other potential causes of vaso-occlusion. Maintaining stable hemodynamic parameters during cardiovascular surgery seems to be the key to prevent visual impairment.

23-gauge transconjunctival sutureless vitrectomy: visual outcomes and complications.

PURPOSE: To report results and complications of 23-gauge transconjunctival sutureless pars plana vitrectomy for a variety of vitreoretinal diseases. METHODS: A prospective consecutive case series study was performed in 66 eyes of 66 patients. Indications for surgery were epiretinal membrane (n = 20), rhegmatogenous retinal detachment (n = 19: 14 pseudophakic, 5 phakic), macular hole (n = 16), vitreous hemorrhage (n = 5), cyclodialysis (n = 1), intraocular lens luxation (n = 1), asteroid hyalosis (n = 1), congenital retinoschisis (n = 1), and endophtalmitis (n = 2). Main outcome measures included visual acuity, intraocular pressure, and intra- and post-operative complications. RESULTS: Mean patient age at time of operation was 68 ± 12 years. Overall, visual acuity improved from 1.03 ± 1.00 logMAR preoperatively to 0.32 ± 0.33 logMAR postoperatively (p < 0.01) after a mean follow-up time of 9.3 ± 4.7 months. Mean preoperative intraocular pressure was 13.9 ± 3.5 mmHg, and mean postoperative intraocular pressure was 17.9 ± 9.6 mmHg on day 1 (p < 0.01) and 14.7 ± 2.8 mmHg (p = 0.05) at final visit. Concerning complications, 2 cases of hypotony and 7 of hypertony occurred on day 1, a macular hole reopened some weeks later, and a retinal detachment recurred in one case. CONCLUSION: 23-gauge transconjunctival sutureless vitrectomy is an effective and safe technique for a variety of vitreoretinal diseases.

Idiopathic macular epiretinal membrane surgery and ILM peeling: anatomical and functional outcomes.

PURPOSE: Evaluation of the visual and anatomical outcomes following idiopathic macular epiretinal membrane (ERM) removal, with or without internal limiting membrane (ILM) peeling, and review of the literature. METHODS: A retrospective study of 39 eyes operated for idiopathic ERM was conducted. Pars plana vitrectomy was combined with ERM removal and Indocyanine green (ICG) assisted ILM peeling in 24 eyes. RESULTS: In Group A (without ILM peeling), mean preoperative BCVA was 0.48 logMAR (0.3 in decimal units), whereas mean postoperative BCVA was 0.37 logMAR (0.4 in decimal units). In Group B (with ILM peeling), mean preoperative BCVA was 0.58 logMAR (0.25 in decimal units), whereas mean postoperative BCVA was 0.31 logMAR (0.5 in decimal units). No statistically significant difference was observed between Groups A and B regarding preoperative or postoperative BCVA (p>0.1, Student's t-test). OCT measurement of postoperative foveal thickness reveled a significant decrease in thickness in both groups; however, no correlation was observed between postoperative BCVA and postoperative foveal thickness (Pearson's correlation coefficient = 0.139; p>0.1). CONCLUSIONS: In spite of final visual acuity improvement following idiopathic ERM removal, recovery of a normal foveal thickness is not achieved in the majority of the cases. ICG assisted ILM peeling does not affect the functional outcome of idiopathic ERM removal.

Vasomotor effect of intravitreal juxta-arteriolar injection of L-lactate on the retinal arterioles after acute branch retinal vein occlusion in minipigs.

PURPOSE: To investigate the effect of L-lactate on retinal arteriolar diameter after acute branch retinal vein occlusion (BRVO) in minipigs. METHODS: Thirteen eyes of 13 minipigs were evaluated, with the animals under general anesthesia. BRVO was induced by a standard method of argon laser endophotocoagulation. Two hours after BRVO, an intravitreal, juxta-arteriolar microinjection of 50 µL L-lactate 0.5 M (pH 7.4) was performed in nine eyes. Four eyes received a microinjection of 50 µL of the solvent (pH 7.4) that was used to prepare the solution of L-lactate and served as controls. Retinal arteriolar diameter changes were measured using a retinal vessel analyzer. RESULTS: Overall (n = 13), 2 hours after BRVO, there was a 9.0% ± 1.4% decrease in the retinal arteriolar diameter in the affected ares compared to baseline (P < 0.001). An increase of 26.2% ± 8.2% (P = 0.004) of the arteriolar diameter was evidenced 5 minutes after L-lactate juxta-arteriolar microinjection (n = 9) compared with the diameter before L-lactate microinjection. Thereafter, the vasodilatory effect of L-lactate persisted and remained significant until the end of the study period (27.7% ± 7.8% at 30 minutes) compared with the diameter before L-lactate microinjection (P = 0.002). Microinjection of the solvent alone (n = 4) did not produce any significant effect on the retinal arterioles, which remained constricted at all time-points (P > 0.1). CONCLUSIONS: These findings demonstrate a significant arteriolar vasodilation after intravitreal juxta-arteriolar L-lactate microinjection in eyes with experimental BRVO in the affected areas. L-lactate microinjection can reverse the arteriolar vasoconstriction that occurs in acute experimental BRVO.

Association of ranibizumab (Lucentis®) or bevacizumab (Avastin®) with dexamethasone and triamcinolone acetonide: an in vitro stability assessment.

The in vitro stability of monoclonal antibodies used for age-related macular degeneration, ranibizumab and bevacizumab, was investigated. The aggregation profile of the antibodies was compared, alone and after association with dexamethasone sodium phosphate or triamcinolone acetonide. Commercial formulations of ranibizumab and bevacizumab were dialysed into three different buffers. After dialysis, samples were stored at 4°C, 25°C and 40°C during 35 days, alone and in combination with dexamethasone sodium phosphate, triamcinolone acetonide phosphate solution or triamcinolone acetonide suspension. Combined formulations based on both commercial formulations were investigated as well. The aggregation state of the antibodies was measured by multi-angle light scattering (MALS) after separation by asymmetrical flow field-flow fractionation (AFFF) or size-exclusion chromatography (SEC). Ranibizumab results to be more stable than bevacizumab, alone and in combination with dexamethasone sodium phosphate or triamcinolone acetonide. Elevation in concentration, pH and temperature causes a decrease in stability of both antibodies. The association of triamcinolone acetonide phosphate solution with either ranibizumab or bevacizumab is observed to be the least stable combination of all samples tested. Dexamethasone sodium phosphate was shown to have a stabilizing effect on bevacizumab, although this is not the case for its combination with the commercial formulation Avastin®. The results demonstrate that the in vitro association of either ranibizumab or bevacizumab with dexamethasone sodium phosphate or triamcinolone acetonide suspension does not decrease the stability of these antibodies. Although ranibizumab is more stable than bevacizumab in vitro, further research has to point out how this affects their mechanism of action in vivo.

Pars plana vitrectomy in the treatment of severe complicated toxoplasmic retinochoroiditis.

PURPOSE: To present the anatomic and functional results of pars plana vitrectomy performed in severe complicated toxoplasmic retinochoroiditis. METHODS: Three patients, 2 women and 1 man aged 57, 22, and 57 years, are presented. The first patient was under immunosuppressive therapy for dermatomyositis and underwent diagnostic/therapeutic vitrectomy for severe toxoplasmic panuveitis with dense vitritis. The other 2 patients underwent vitrectomy for macula-off rhegmatogenous retinal detachment that developed after severe toxoplasmic panuveitis. RESULT: Preoperative visual acuity was hand movement for the first 2 patients and 20/400 for the third. All patients received pars plana vitrectomy with epiretinal membrane peeling, laser photocoagulation, and SF6 gas tamponade. The second and third patients needed 5 and 3 additional operations, respectively, including extensive retinotomies and silicone-oil tamponade, for recurrent retinal detachment due to proliferative vitreoretinopathy. At the end of the follow-up period (11, 5, and 1 year, respectively), the retina was attached and visual acuity was 20/30 for the first patient but counting fingers for the other 2 patients. CONCLUSIONS: Severe panuveitis and/or recurrent retinal detachment may develop in some cases of ocular toxoplasmosis, compromising the visual prognosis. Retinal detachment due to toxoplasmosis is generally complex, and long-acting tamponade with silicone oil should be contemplated for anatomic retinal reattachment.