Saccadic movements assessment in eccentric fixation: A study in patients with Stargardt disease.

PURPOSE: To investigate saccadic movements in subjects with eccentric fixation due to a deep central scotoma in Stargardt disease (STGD). METHODS: We studied 10 patients with STGD and 10 healthy subjects (control group). Saccadic movements of all the 20 subjects were assessed by using the eye tracker technique Tobii Glasses Pro 2. Standard measurements of reading ability (MNREAD charts), visual acuity (ETDRS charts), contrast sensitivity (Pelli-Robson charts), reading contrast threshold and speed (REX charts), retinal sensitivity and stability and localization of the fixation (MP1 fundus perimetry) were obtained in all subjects. RESULTS: The saccadic movements time was significantly slower in STGD than in healthy subjects (699 ± 193 ms vs 299 ± 40 ms, p < 0.001). When STGD patients moved fixation to the target localized in retinal scotomatous areas, the movement was significantly slower compared to non scotomatous areas in the retina (1103 ± 798 ms vs 524 ± 187 ms, p = 0.039). There was a trend toward a correlation between slow saccadic movements in STGD subjects and the reading performance indices, although statistical significance was not achieved. CONCLUSION: Ocular saccades guided by eccentric fixation in STGD patients are significantly slower than in the control group, especially when the target corresponds to retinal areas with a deep scotoma. These results can explain the worse reading performance in STGD subjects, in particular when a non-viewing area on the right part of the text is present.

Spatiotemporal representation of long-delayed systems: An alternative approach.

Dynamical systems with long-delay feedback can exhibit complicated temporal phenomena, which once reorganized in a two-dimensional space are reminiscent of spatiotemporal behavior. In this framework, a normal forms description has been developed to reproduce the dynamics, and the opportunity to treat the corresponding variables as true space and time has since been established. However, recently, an alternative approach has been proposed [F. Marino and G. Giacomelli, Phys. Rev. E 98, 060201(R) (2018)2470-004510.1103/PhysRevE.98.060201] with a different interpretation of the variables involved, which better takes into account their physical character and allows for an easier determination of the normal forms. In this paper, we extend such idea and apply it to a number of paradigmatic examples, paving the way to a rethinking of the concept of spatiotemporal representation of long-delayed systems.

Long-term follow-up and "double layer sign" in patients affected by circumscribed choroidal hemangioma.

BACKGROUND: Photodynamic therapy has revolutionised the treatment of circumscribed choroidal hemangiomas. The aim of this report is to report the long-term follow-up of patients affected by circumscribed choroidal hemangioma treated using photodynamic therapy. MATERIALS AND METHODS: We retrospectively reviewed patients affected by circumscribed choroidal hemangioma examined at the Retinal Medical Department at the Eye Clinic in Florence. We studied circumscribed choroidal hemangiomas treated using photodynamic therapy with at least 1 follow-up examination. Verteporfin was administered intravenously for 10 min (6 mg/m2 body surface area). After infusion (5 min), a 689 nm laser was applied with a light dose of 50 J/cm2. RESULTS: Ten eyes of 10 patients with circumscribed choroidal hemangioma who underwent Photodynamic therapy were included in our series (2 females and 8 males; average age at diagnosis 47.8 ± 9.3 yrs.; age range: 27-56 years). Five patients (5/10; 50 %) received only the photodynamic treatment whereas 5 patients (5/10; 50 %) also received other treatments (laser photocoagulation, intravitreal injection). On average, the patients received 2 photodynamic treatments (range 1-4). Four patients (4/10, 40 %) had a > 5-year follow-up; (average 4.5 ± 3.7 yrs. range 6 months - 10 years). In 2 patients we identified the "double layer sign" at the optical coherence tomography examination on circumscribed choroidal hemangioma. CONCLUSIONS: In our series, photodynamic therapy was a safe and effective treatment for circumscribed choroidal hemangioma during long-term follow-up. The double layer sign, which can be detected in several choroidal pathologies, suggests common pathogenetic mechanisms for circumscribed choroidal hemangiomas and central serous chorioretinopathy/polypoidal choroidopathy spectrum disease.

The Veterans Affairs Low-Vision Visual Functioning Questionnaire-48 (VA LV VFQ-48): Performance of the Italian version.

PURPOSE: The Veterans Affairs Low-Vision Visual Functioning Questionnaire-48 is among the most validated tools to collect patient-reported outcomes in a low-vision population. We have aimed to conduct a pilot validation of the Italian version of the Veterans Affairs Low-Vision Visual Functioning Questionnaire-48. METHODS: The Veterans Affairs Low-Vision Visual Functioning Questionnaire-48 was translated using a standardized procedure and then administered to consecutive low-vision patients attending rehabilitation services in three centers. Patients were interviewed by a trained psychologist regarding the individual items of the tool. RESULTS: We included 131 patients with a mean visual acuity of 0.91 logMAR (standard deviation: 0.42 logMAR), mostly affected by age-related macular degeneration. The Veterans Affairs Low-Vision Visual Functioning Questionnaire-48 showed high internal consistency (Cronbach's alpha: 0.98) and good item-test and item-rest correlation (median: 0.73 and 0.71, respectively). Both the overall score and the subscale (reading, visual motor, mobility and visual information) scores significantly correlated with visual acuity, reading acuity and speed. Reading speed achieved the best absolute correlation with the Veterans Affairs Low-Vision Visual Functioning Questionnaire-48 scores (Spearman r: 0.39-0.49). CONCLUSION: The Italian version of the Veterans Affairs Low-Vision Visual Functioning Questionnaire-48 is a valid tool to assess patients attending low-vision services. Revising a few items may further improve the tool.

Relationship Between Acuity and Contrast Sensitivity: Differences Due to Eye Disease.

Purpose: Visual acuity (VA) and contrast sensitivity (CS) characterize different aspects of visual function. Whereas VA is a standard test in routine eye exams and clinical trials, CS is often not included. We investigated the pathology-specific dissociation between VA and CS by quantifying and comparing the relationship between these two measures in common ocular pathologies. Methods: VA and CS data were assembled from 1113 subjects, including groups with cataract (n = 450), age-related macular degeneration (AMD; n = 232), glaucoma (n = 100), retinitis pigmentosa (RP; n = 87), and normal ocular health (n = 244). VA and CS were measured by the Early Treatment Diabetic Retinopathy Study chart and Pelli-Robson chart, respectively. Results: Even when VA was relatively normal (<0.3 logMAR), the four ocular pathology groups showed quantitatively different mean CS deficits relative to normal controls, ranging from -0.01 log units for cataract to 0.23 log units for RP. When the entire range of VA was considered, the corresponding deficits in CS were noticeably different across these four groups, being least for cataract and progressively more severe for glaucoma, AMD, and RP. For every 1.0 logMAR loss of VA, the corresponding deficit in CS ranged from 0.22 logCS for cataract to 0.97 logCS for RP. Conclusions: The quantitative relationship between VA and CS depends on the ocular pathology. CS appears to provide valuable complementary information to VA in the early detection of eye disease and when evaluating visual impairment.

Excitable Wave Patterns in Temporal Systems with Two Long Delays and their Observation in a Semiconductor Laser Experiment.

Excitable waves arise in many spatially extended systems of either a biological, chemical, or physical nature due to the interplay between local reaction and diffusion processes. Here we demonstrate that similar phenomena are encoded in the time dynamics of an excitable system with two, hierarchically long delays. The transition from 1D localized structures to curved wave segments is experimentally observed in an excitable semiconductor laser with two feedback loops and reproduced by numerical simulations of a prototypical model. While closely related to those found in 2D excitable media, wave patterns in delayed systems exhibit unobserved features originating from causality related constraints. An appropriate dynamical representation of the data uncovers these phenomena and permits us to interpret them as the result of an effective 2D advection-reaction-diffusion process.

Evidence of a Critical Phase Transition in Purely Temporal Dynamics with Long-Delayed Feedback.

Experimental evidence of an absorbing phase transition, so far associated with spatiotemporal dynamics, is provided in a purely temporal optical system. A bistable semiconductor laser, with long-delayed optoelectronic feedback and multiplicative noise, shows the peculiar features of a critical phenomenon belonging to the directed percolation universality class. The numerical study of a simple, effective model provides accurate estimates of the transition critical exponents, in agreement with both theory and our experiment. This result pushes forward a hard equivalence of nontrivial stochastic, long-delayed systems with spatiotemporal ones and opens a new avenue for studying out-of-equilibrium universality classes in purely temporal dynamics.

Reading aids for adults with low vision.

BACKGROUND: The purpose of low-vision rehabilitation is to allow people to resume or to continue to perform daily living tasks, with reading being one of the most important. This is achieved by providing appropriate optical devices and special training in the use of residual-vision and low-vision aids, which range from simple optical magnifiers to high-magnification video magnifiers. OBJECTIVES: To assess the effects of different visual reading aids for adults with low vision. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2017, Issue 12); MEDLINE Ovid; Embase Ovid; BIREME LILACS, OpenGrey, the ISRCTN registry; ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). The date of the search was 17 January 2018. SELECTION CRITERIA: This review includes randomised and quasi-randomised trials that compared any device or aid used for reading to another device or aid in people aged 16 or over with low vision as defined by the study investigators. We did not compare low-vision aids with no low-vision aid since it is obviously not possible to measure reading speed, our primary outcome, in people that cannot read ordinary print. We considered reading aids that maximise the person's visual reading capacity, for example by increasing image magnification (optical and electronic magnifiers), augmenting text contrast (coloured filters) or trying to optimise the viewing angle or gaze position (such as prisms). We have not included studies investigating reading aids that allow reading through hearing, such as talking books or screen readers, or through touch, such as Braille-based devices and we did not consider rehabilitation strategies or complex low-vision interventions. DATA COLLECTION AND ANALYSIS: We used standard methods expected by Cochrane. At least two authors independently assessed trial quality and extracted data. The primary outcome of the review was reading speed in words per minute. Secondary outcomes included reading duration and acuity, ease and frequency of use, quality of life and adverse outcomes. We graded the certainty of the evidence using GRADE. MAIN RESULTS: We included 11 small studies with a cross-over design (435 people overall), one study with two parallel arms (37 participants) and one study with three parallel arms (243 participants). These studies took place in the USA (7 studies), the UK (5 studies) and Canada (1 study). Age-related macular degeneration (AMD) was the most frequent cause of low vision, with 10 studies reporting 50% or more participants with the condition. Participants were aged 9 to 97 years in these studies, but most were older (the median average age across studies was 71 years). None of the studies were masked; otherwise we largely judged the studies to be at low risk of bias. All studies reported the primary outcome: results for reading speed. None of the studies measured or reported adverse outcomes.Reading speed may be higher with stand-mounted closed circuit television (CCTV) than with optical devices (stand or hand magnifiers) (low-certainty evidence, 2 studies, 92 participants). There was moderate-certainty evidence that reading duration was longer with the electronic devices and that they were easier to use. Similar results were seen for electronic devices with the camera mounted in a 'mouse'. Mixed results were seen for head-mounted devices with one study of 70 participants finding a mouse-based head-mounted device to be better than an optical device and another study of 20 participants finding optical devices better (low-certainty evidence). Low-certainty evidence from three studies (93 participants) suggested no important differences in reading speed, acuity or ease of use between stand-mounted and head-mounted electronic devices. Similarly, low-certainty evidence from one study of 100 participants suggested no important differences between a 9.7'' tablet computer and stand-mounted CCTV in reading speed, with imprecise estimates (other outcomes not reported).Low-certainty evidence showed little difference in reading speed in one study with 100 participants that added electronic portable devices to preferred optical devices. One parallel-arm study in 37 participants found low-certainty evidence of higher reading speed at one month if participants received a CCTV at the initial rehabilitation consultation instead of a standard low-vision aids prescription alone.A parallel-arm study including 243 participants with AMD found no important differences in reading speed, reading acuity and quality of life between prism spectacles and conventional spectacles. One study in 10 people with AMD found that reading speed with several overlay coloured filters was no better and possibly worse than with a clear filter (low-certainty evidence, other outcomes not reported). AUTHORS' CONCLUSIONS: There is insufficient evidence supporting the use of a specific type of electronic or optical device for the most common profiles of low-vision aid users. However, there is some evidence that stand-mounted electronic devices may improve reading speeds compared with optical devices. There is less evidence to support the use of head-mounted or portable electronic devices; however, the technology of electronic devices may have improved since the studies included in this review took place, and modern portable electronic devices have desirable properties such as flexible use of magnification. There is no good evidence to support the use of filters or prism spectacles. Future research should focus on assessing sustained long-term use of each device and the effect of different training programmes on its use, combined with investigation of which patient characteristics predict performance with different devices, including some of the more costly electronic devices.

Pseudo-spatial coherence resonance in an excitable laser with long delayed feedback.

The effect of noise in an excitable semiconductor laser with feedback is studied in the framework of the spatio-temporal representation of long delayed systems. Propagation, noise-induced creation, and destruction of excitable pulses in the pseudo time are observed. The addition of a variable quantity of noise leads to the occurrence of a phenomenon that we term "pseudo-spatial coherence resonance." A phenomenological model well describes the system and allows for a comparison with the experimental observations. A simple Monte Carlo approach is also introduced and permits to explain the features observed in terms of the key dynamical ingredients of the physical system.

Aflibercept in Serous Foveal Detachment in Dome-Shaped Macula: Short-Term Results in a Retrospective Study.

BACKGROUND AND OBJECTIVE: To evaluate short-term efficacy of intravitreal aflibercept (Eylea; Regeneron, Tarrytown, NY) in serous foveal detachment (SFD) in dome-shaped macula (DSM). PATIENTS AND METHODS: A retrospective, noncomparative case series. Three monthly aflibercept injections were administered. Early Treatment Diabetic Retinopathy Study best-corrected visual acuity (BCVA), optical coherence tomography central subfield thickness (CST), and subretinal fluid (SRF) at baseline and at 2 months and 4 months after the last injection were considered for statistical analysis. RESULTS: The authors reviewed nine eyes affected by SFD in DSM. Mean BCVA improved from 0.42 LogMAR at baseline to 0.33 LogMAR at final follow-up (P = .06), and mean CST and SRF reduced from 347 µm to 295 µm (P = .09) and from 146 µm to 99 µm (P < .01), respectively. None of the considered eyes had resolution of the SRF. CONCLUSIONS: Three monthly aflibercept injections may improve BCVA and reduce CST and SRF in SFD of DSM. Further prospective studies are necessary to state the real efficacy of this approach. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:822-828.].

Splitting in the pinning-depinning transition of fronts in long-delayed bistable systems.

We investigate the formation of localized domains through front pinning in a periodically forced, bistable semiconductor laser with long-delayed optoelectronic feedback. At difference with 1D spatially extended systems, the transition from the pinning to the propagation regime occurs via two separated bifurcations, each corresponding to the unpinning of one of the fronts surrounding the localized domain. The bifurcation splitting is systematically explored, unveiling the crucial role played by the forcing frequency. The experimental results are reproduced and interpreted by means of a prototypical model of our system.

Long-Term Follow-Up of Choroidal Neovascularization due to Angioid Streaks with pro re nata Intravitreal Anti-VEGF Treatment.

PURPOSE: To evaluate the long-term outcomes of intravitreal anti-vascular endothelial growth factor (VEGF) drugs with a pro re nata (PRN) regimen for the treatment of choroidal neovascularization (CNV) secondary to angioid streaks (AS). METHODS: This is a retrospective, multicenter, noncomparative case series of consecutive AS eyes affected by treatment-naïve CNV. A complete ophthalmologic examination was performed every 30-45 days after the loading phase, including fluorescein angiography and/or optical coherence tomography. RESULTS: In all, 52 eyes of 39 patients were treated with intravitreal bevacizumab and/or ranibizumab and followed up for a mean of 33.8 months. The best corrected visual acuity at baseline was 20/40, and it deteriorated by an average of 6.8 ETDRS letters per year (p < 0.001). We performed an average of 5.1, 6.5, and 6.8 injections at the 1-, 2-, and 3-year follow-up, respectively. CONCLUSIONS: Intravitreal anti-VEGF drugs in a PRN regimen with close monitoring appear to slow the progression of CNV in AS, but they do not prevent the affected eyes from progressive visual loss.

Reading Ability and Quality of Life in Stargardt Disease.

PURPOSE: To study the reading performance of patients with Stargardt disease (STGD) and the relationship between clinical vision measurements and vision-related quality of life (VRQOL). METHODS: We studied both eyes of 16 patients with STGD. Each patient was examined for best-corrected visual acuity (Early Treatment Diabetic Retinopathy Study [ETDRS]), reading ability (MNREAD and REX charts), contrast sensitivity (Pelli-Robson charts), fixation study (MP1 microperimeter), and VRQOL (25-item National Eye Institute Visual Function Questionnaire [NEI VFQ-25]). The correlation pattern among these variables was examined and an exploratory factor analysis was used to investigate dimensionality of both visual function and VRQOL. RESULTS: Mean ETDRS visual acuity was about 20/160 (0.9 logMAR). All studied psychophysical measures were highly or moderately correlated with MNREAD reading speed (p<0.05 level). A similar correlation was found between psychophysical measures and VRQOL, which was higher for MNREAD measures of acuity (r = -0.75) and speed (r = 0.74). Accordingly, exploratory factor analysis suggested that a single latent dimension explained most of the variance of vision psychophysical measures as well as of VRQOL. CONCLUSIONS: We propose that reading ability should be assessed in patients with STGD, since we found that both MNREAD reading speed and visual acuity are strong determinants of quality of life. The observed relation between reading ability and VRQOL in STGD suggests that in these patients appropriate low vision rehabilitation can improve both reading performance and consequently VRQOL. Finally, our data support the use of reading speed and visual acuity as important outcome measures for monitoring STGD progression.

Complex Active Optical Networks as a New Laser Concept.

Complex optical networks containing one or more gain sections are investigated, and the evidence of lasing action is reported; the emission spectrum reflects the topological disorder induced by the connections. A theoretical description compares well with the measurements, mapping the networks to directed graphs and showing the analogies with the problem of quantum chaos on graphs. We show that the interplay of chaotic diffusion and amplification leads to an emission statistic with characteristic heavy tails: for different topologies, an unprecedented experimental demonstration of Lévy statistics expected for random lasers is here provided for a continuous-wave pumped system. This result is also supported by a Monte Carlo simulation based on the ray random walk on the graph.

Dynamical systems with multiple long-delayed feedbacks: Multiscale analysis and spatiotemporal equivalence.

Dynamical systems with multiple, hierarchically long-delayed feedback are introduced and studied extending our previous work [Yanchuk and Giacomelli, Phys. Rev. Lett. 112, 174103 (2014)]. Focusing on the phenomenological model of a Stuart-Landau oscillator with two feedbacks, we show the multiscale properties of its dynamics and demonstrate them by means of a space-time representation. For sufficiently long delays, we derive a normal form describing the system close to the destabilization. The space and temporal variables, which are involved in the space-time representation, correspond to suitable time scales of the original system. The physical meaning of the results, together with the interpretation of the description at different scales, is presented and discussed. In particular, it is shown how this representation uncovers hidden multiscale patterns such as spirals or spatiotemporal chaos. The effect of the delay size and the features of the transition between small and large delays is also analyzed. Finally, we comment on the application of the method and on its extension to an arbitrary, but finite, number of delayed feedback terms.

Ocular surface temperature in age-related macular degeneration.

Background. The aim of this study is to investigate the ocular thermographic profiles in age-related macular degeneration (AMD) eyes and age-matched controls to detect possible hemodynamic abnormalities, which could be involved in the pathogenesis of the disease. Methods. 32 eyes with early AMD, 37 eyes with atrophic AMD, 30 eyes affected by untreated neovascular AMD, and 43 eyes with fibrotic AMD were included. The control group consisted of 44 healthy eyes. Exclusion criteria were represented by any other ocular diseases other than AMD, tear film abnormalities, systemic cardiovascular abnormalities, diabetes mellitus, and a body temperature higher than 37.5°C. A total of 186 eyes without pupil dilation were investigated by infrared thermography (FLIR A320). The ocular surface temperature (OST) of three ocular points was calculated by means of an image processing technique from the infrared images. Two-sample t-test and one-way analysis of variance (ANOVA) test were used for statistical analyses. Results. ANOVA analyses showed no significant differences among AMD groups (P value >0.272). OST in AMD patients was significantly lower than in controls (P > 0.05). Conclusions. Considering the possible relationship between ocular blood flow and OST, these findings might support the central role of ischemia in the pathogenesis of AMD.

Clinical outcomes and rotational stability of a 4-haptic toric intraocular lens in myopic eyes.

PURPOSE: To evaluate the refractive outcomes and rotational stability of a 4-haptic toric intraocular lens (IOL) in myopic eyes and the correlations between IOL rotation and refractive sphere, axial length (AL), and white-to-white (WTW) diameter. SETTING: Eye Clinic, Careggi Hospital, Florence, Italy. DESIGN: Prospective case series. METHODS: Phacoemulsification cataract extraction and implantation of an AT Torbi 709M IOL were performed. Corneal astigmatism was 1.50 diopters (D) or greater and the AL between 25.0 mm and 27.0 mm in all eyes. The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, and IOL axis were evaluated preoperatively and postoperatively up to 6 months. RESULTS: The study enrolled 20 eyes (20 patients). The UDVA and CDVA improved significantly postoperatively (P<.001). The mean refractive spherical equivalent decreased significantly from -7.10 D±1.78 (SD) preoperatively to -0.55±0.25 D 1 day postoperatively (P<.001) and remained stable thereafter. Vector analysis showed that 90% and 85% of the eyes were within ±0.25 D for J0 and J45, respectively. At 3 months and 6 months, the mean IOL rotation was 2.66±1.53 degrees and 3.00±1.69 degrees, respectively (P<.001), with 95% of eyes and 90% of eyes, respectively, within ±5 degrees. A positive correlation was found between IOL rotation and preoperative sphere; none was found with AL and WTW. CONCLUSIONS: Implantation of the 4-haptic toric IOL in myopic eyes was effective and safe. The IOL showed no significant rotation over the 6-month follow-up. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Pattern formation in systems with multiple delayed feedbacks.

Dynamical systems with complex delayed interactions arise commonly when propagation times are significant, yielding complicated oscillatory instabilities. In this Letter, we introduce a class of systems with multiple, hierarchically long time delays, and using a suitable space-time representation we uncover features otherwise hidden in their temporal dynamics. The behavior in the case of two delays is shown to "encode" two-dimensional spiral defects and defects turbulence. A multiple scale analysis sets the equivalence to a complex Ginzburg-Landau equation, and a novel criterium for the attainment of the long-delay regime is introduced. We also demonstrate this phenomenon for a semiconductor laser with two delayed optical feedbacks.

Results of intravitreal ranibizumab with a prn regimen in the treatment of extrafoveal and juxtafoveal neovascular membranes in age-related macular degeneration.

PURPOSE: To evaluate the efficacy of intravitreal ranibizumab with a "pro re nata" regimen in the treatment of nonsubfoveal neovascular membranes secondary to age-related macular degeneration. METHODS: Retrospective noncomparative case series. Thirty-one eyes with naive nonsubfoveal neovascularization secondary to age-related macular degeneration were consecutively enrolled and treated with ranibizumab intravitreal injections according to a pro re nata regimen. The follow-up was performed monthly up to 6 months and quarterly up to 2 years (25 patients). Early treatment diabetic retinopathy study best-corrected visual acuity and lesion size analysis with fluorescein angiography were recorded. RESULTS: The mean baseline early treatment diabetic retinopathy study best-corrected visual acuity worsened from 20/40 (0.28 logMAR) at baseline to 20/50 (0.42 logMAR) at 1-year follow-up and 20/60 (0.53 logMAR) at 2-year follow-up. The mean lesions size nearly doubled from baseline at the 2-year follow up (1.19-2.47 mm). Twenty-two patients had one or more recurrences at 1-year follow-up. All 25 patients developed a recurrence at 2 years with 7 cases developing a recurrence by 12 months. Twelve cases progressed to subfoveal lesions by the 24-month visit. CONCLUSION: Other regimens described in the literature might result in a more the satisfactory outcome using more frequent follow-up and more frequent intravitreal injections.

Front pinning and localized states analogues in long-delayed bistable systems.

Localized structures have been observed in many spatially extended systems of either biological, chemical, or physical nature. Here, we study experimentally front pinning and dissipative localized structures in a delayed optical system based on a bistable semiconductor laser with optoelectronic feedback. We observe that many of the concepts known to apply to spatially localized structures also apply in this context, with specificities related to the lack of reversibility symmetry. Numerical simulations based on purely prototypical modeling reproduce very well the experimental findings, which indicates that the results do not depend on the specific physical system under consideration, but are, on the contrary, very generic features of time delayed systems.