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Optogenetics may enable mutation-independent, circuit-specific restoration of neuronal function in neurological diseases. Retinitis pigmentosa is a neurodegenerative eye disease where loss of photoreceptors can lead to complete blindness. In a blind patient, we combined intraocular injection of an adeno-associated viral vector encoding ChrimsonR with light stimulation via engineered goggles. The goggles detect local changes in light intensity and project corresponding light pulses onto the retina in real time to activate optogenetically transduced retinal ganglion cells. The patient perceived, located, counted and touched different objects using the vector-treated eye alone while wearing the goggles. During visual perception, multichannel electroencephalographic recordings revealed object-related activity above the visual cortex. The patient could not visually detect any objects before injection with or without the goggles or after injection without the goggles. This is the first reported case of partial functional recovery in a neurodegenerative disease after optogenetic therapy.

International audience; PurposeTo describe the application of OCT-A in various posterior uveitis disorders in our experience and to compare it with the available literature.MethodsEighteen eyes with the diagnoses of multifocal choroiditis (MFC), multifocal placoid pigment epitheliopathy (APMPPE), multiple evanescent white dot syndrome (MEWDS), tuberculous serpiginous-like choroiditis (SLC), serpiginous choroiditis (SC), and birdshot chorioretinopathy (BSCR) were studied.ResultsWe found flow void of the choriocapillaris in patients with APMPPE, SC, MFC, BSCR, and in SLC. In contrast, perfusion of the choriocapillaris seemed normal in patients with MEWDS.ConclusionsWe confirmed that OCT-A contributes new information on the physiopathology of white dot syndromes and inflammatory chorioretinopathies, notably on whether or not the choriocapillaris is involved. Comparing the OCT-A features allowed us to suggest that both APMPPE and SLC might be part of the same spectrum of inflammatory disease with primary involvement at the level of the choriocapillaris and secondary RPE damage.

Purpose To characterize evolution of macular injury from a high-powered blue handheld laser using multimodal imaging and describe successful surgical treatment. Methods Observational clinical case report. Results A 17-year-old boy presented with unilateral acute loss of vision with discrete white macular lesions, full-thickness disruption of retinal layers, and hyperreflective material at the fovea on optical coherence tomography caused by exposure to a 445 nm blue-light handheld laser with power up to 2,000 mW characterized as a Class IV laser. The injury evolved into an approximately 950-μm full-thickness macular hole 3 weeks later with visual acuity of 20/400. Vitrectomy and internal limiting membrane peel resulted in anatomic success and final vision at 4 months of 20/25. Conclusion High-powered lasers can induce significant disruption of retinal layers, inflammatory debris, and full-thickness macular holes with momentary exposure that, despite poor anatomic prognostic factors, can have successful surgical outcomes.

To evaluate alterations in treatment burden and course of exudative age-related macular degeneration in patients who contracted endophthalmitis from intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections.Retrospective study at the University of Pittsburgh Medical Center examining frequency of anti-VEGF injections, activity of choroidal neovascularization, and visual acuity before and after endophthalmitis treatment.Twenty-one patients meeting inclusion criteria were identified, of whom 7 (33%) patients did not restart anti-VEGF treatment 12 months after endophthalmitis because of quiescence of exudative age-related macular degeneration without significant visual acuity loss (P0.05). Patients who resumed anti-VEGF treatment exhibited 32% and 38% decreases in injection frequency by 12 and 24 months after endophthalmitis, respectively (P0.05). On first optical coherence tomography follow-up, 10 patients exhibited quiescence of choroidal neovascularization activity, although there were no measurable changes in macular thickness (P0.05). No differences in post-endophthalmitis exudative age-related macular degeneration progression or treatment burden were observed when factoring adjuvant intravitreal steroid therapy, culture results, nor choroidal neovascularization subtypes.Endophthalmitis resolution is associated with a decrease in choroidal neovascularization activity and a reduction of anti-VEGF treatment burden in patients with exudative age-related macular degeneration.

Purpose To report refractive outcomes of scleral-fixated intraocular lens (IOL) implantation with Gore-Tex (W.L. Gore & Associates, Newark, DE) suture and combined pars plana vitrectomy and compare predicted refractive outcomes among 5 IOL power calculation formulas. Design Retrospective case series. Participants Patients undergoing scleral-fixated IOL implantation with Gore-Tex suture at our institution between January 2015 and June 2018. Methods Comparison of preoperative biometrics with postoperative refraction and calculation of predicted refractive outcome with 5 different IOL formulas. Main Outcome Measures Prediction error and absolute error to compare postoperative refraction with refraction predicted by lens power calculation formulas. Results Thirty-one eyes of 31 patients were included. All power calculations assumed in-the-bag position of the IOL. The Akreos A060 (Bausch & Lomb, Rochester, NY) was implanted in 23 eyes and the CZ70BD (Alcon, Fort Worth, TX) in 8 eyes, and all lenses were sutured 3 mm behind the limbus. Average postoperative spherical equivalent (SE) was –0.79±0.95 diopters (D). Average prediction error (postoperative SE refraction minus target refraction) was –0.19±0.72 D. Postoperative SE was within 1.0 D of target in 25 of 31 patients (81%) and 2.0 D of target in 31 of 31 patients (100%). The repeated-measures analysis of variance of absolute error by lens power formula was significant (P = 0.012), with Haigis demonstrating greater error. There was no significant difference among Barrett II, Sanders-Retzlaff-Kraff theoretical (SRK/T), Holladay 2, or Hoffer Q. Conclusions For eyes undergoing pars plana vitrectomy with scleral-sutured IOL implantation, assumption of in-the-bag IOL position when calculating lens power leads to acceptable refractive outcomes. Barrett II, SRK/T, Holladay 2, and Hoffer Q formulas were noninferior to each other.

Purpose: Drusen are dynamic sub-RPE deposits that are risk factors for late-stage agerelated macular degeneration (AMD). Here we show a new imaging method using floodillumination adaptive optics (FIAO) that reveal drusen with high contrast and resolution. Methods: A fovea-centered 4° × 4° FIAO image and eight surrounding images with gaze displaced by ±2° vertically and horizontally were acquired. Clinical color fundus and spectral-domain optical coherence tomography were acquired for clinical grading and comparison. Custom software registered overlapping FIAO images and fused the data statistically to generate a fovea-centered 4° × 4° gaze-dependent image. Our dataset included 15 controls (aged 31–72) and 182 eyes from 104 AMD patients (aged 56–92), graded as either normal aging (n = 7), and early (n = 12), intermediate (n = 108) and late AMD (n = 42); 27 had subretinal drusenoid deposits (SDDs), and 83 were imaged longitudinally. Results: No gaze varying structures were detected in young eyes. In aging eyes with no evidence of age-related changes, putative drusen Translational Relevance: This new technique offers promise as a robust and sensitive method to detect, map, quantify, and monitor the dynamics of drusen in aging and AMD.

Retinal membrane peeling requires delicate manipulation. The presence of the surgeon's physiological tremor, the high variability and often low quality of the ophthalmic image, and excessive forces make the tasks more challenging. Preventing unintended movement caused by tremor and unintentional forces can reduce membrane injury. With the use of an actively stabilized handheld robot, we employ a monocular camera-based surface reconstruction method to estimate the retinal plane and we propose the use of a virtual fixture with the application of a hard stop and motion scaling to improve control of the tool tip during delaminating in a laboratory simulation of retinal membrane peeling. A hard stop helps to limit downward force exerted on the surface. Motion scaling also improves the user's control of contact force when delaminating. We demonstrate a reduction of maximum force and maximum surface-penetration distance from the estimated retinal plane using the proposed technique.

Author(s): Muqit, Mahiul MK; Hubschman, Jean Pierre; Picaud, Serge; McCreery, Douglas B; van Meurs, Jan C; Hornig, Ralf; Buc, Guillaume; Deterre, Martin; Nouvel-Jaillard, Celine; Bouillet, Elodie; Fovet, Claire-Maelle; Hantraye, Philippe; Sahel, Jose; Martel, Joseph N; Le Mer, Yannick | Abstract: PURPOSE:To evaluate the surgical technique for subretinal implantation of two sizes of PRIMA photovoltaic wireless microchip in two animal models, and refine these surgical procedures for human trials. METHODS:Cats and Macaca fascicularis primates with healthy retina underwent vitrectomy surgery and were implanted with subretinal wireless photovoltaic microchip at the macula/central retina. The 1.5mm PRIMA chip was initially studied in feline eyes. PRIMA implant (2mm,1.5mm sizes) arrays were studied in primates. Feasibility of subretinal chip implantation was evaluated with a newly-developed surgical technique, with surgical complications and adverse events recorded. RESULTS:The 1.5mm implant was placed in the central retina of 11 feline eyes, with implantation duration 43-106 days. The 1.5mm implant was correctly positioned into central macula of 11 primate eyes, with follow-up periods of minimum 6 weeks (n = 11), 2 years (n = 2), and one eye for 3 years. One primate eye underwent multi-chip 1.5mm implantation using two 1.5mm chips. The 2mm implant was delivered to 4 primate eyes. Optical coherence tomography confirmed correct surgical placement of photovoltaic arrays in the subretinal space in all 26 eyes. Intraoperative complications in primate eyes included retinal tear, macular hole, retinal detachment, and vitreous hemorrhage that resolved spontaneously. Postoperatively, there was no case of significant ocular inflammation in the 1.5mm implant group. CONCLUSIONS:We report subretinal implantation of 1.5mm and 2mm photovoltaic arrays in the central retina of feline and central macula of primate eyes with a low rate of device-related complications. The in vivo PRIMA implantation technique has been developed and refined for use for a 2mm PRIMA implant in ongoing human trials.

Purpose: The purpose of this article is to examine the clinical outcomes of scleral fixation of intraocular lenses (IOLs) using Gore-Tex suture at our institution. Methods: A retrospective chart review was conducted of patients who underwent scleral fixation of an IOL with Gore-Tex suture with concurrent pars plana vitrectomy. Intraoperative and postoperative complications were assessed. Results: Seventy-four eyes of 74 patients were included with a mean follow-up interval of 210 days (range, 33–720 days). The mean best-corrected visual acuity improved from 20/480 (1.38 logarithm of the minimum angle of resolution [logMAR]) preoperatively to 20/78 (0.59 logMAR) postoperatively ( P < .001). Indications included dislocated lens implant (42), aphakia without capsular support (18), and subluxation of crystalline lens (14). Bausch and Lomb Akreos AO60 IOL was implanted in 52 eyes, Alcon CZ70BD in 15, and Bausch and Lomb enVista MX60 in 6. Postoperative complications included temporary ocular hypertension in 9 eyes (12%), temporary hypotony in 7 (9%), cystoid macular edema in 3 eyes (4%), corneal decompensation in 2 eyes (3%), IOL dislocation requiring exchange in 1 case (1.4%), vitreous hemorrhage in 2 cases (3%), and retinal detachment in 2 cases (3%). There were no cases of postoperative suture breakage or erosion, endophthalmitis, or hyphema. Conclusions: The use of Gore-Tex suture in scleral fixation of posterior chamber IOLs was well tolerated at a mean follow-up interval of 210 days. There were no suture-related complications.

This paper presents techniques for robot-aided intraocular surgery using monocular vision in order to overcome erroneous stereo reconstruction in an intact eye. We propose a new retinal surface estimation method based on a structured-light approach. A handheld robot known as the Micron enables automatic scanning of a laser probe, creating projected beam patterns on the retinal surface. Geometric analysis of the patterns then allows planar reconstruction of the surface. To realize automated surgery in an intact eye, monocular hybrid visual servoing is accomplished through a scheme that incorporates surface reconstruction and partitioned visual servoing. We investigate the sensitivity of the estimation method according to relevant parameters and also evaluate its performance in both dry and wet conditions. The approach is validated through experiments for automated laser photocoagulation in a realistic eye phantom in vitro. Finally, we present the first demonstration of automated intraocular laser surgery in porcine eyes ex vivo.

Purpose To demonstrate the efficacy and safety of once-daily nepafenac 0.3% ophthalmic suspension versus vehicle, based on clinical outcomes, after cataract surgery in patients with diabetes. Design Two prospective, randomized, multicenter, double-masked, vehicle-controlled phase 3 studies. Participants Total, 615 patients in study 1 and 605 patients in study 2. Methods Patients were randomized (1:1) to topical nepafenac 0.3% or vehicle once-daily starting the day before surgery and continuing for 90 days thereafter. Main Outcome Measures Key efficacy variables were: patients (%) in whom macular edema (ME) developed (≥30% increase from preoperative baseline central subfield macular thickness) within 90 days after cataract surgery and the patients (%) with a best-corrected visual acuity (BCVA) improvement of ≥15 letters from preoperative baseline through day 14 maintained through day 90. Secondary end points included: patients (%) with a BCVA improvement of ≥15 letters from preoperative baseline through days 90 and 60 and safety over 3 months. Results A significantly lower percentage of patients demonstrated ME within 90 days after surgery with nepafenac 0.3% versus vehicle (study 1: 2.3% vs. 17.3%; P P = 0.001; pooled: 4.1% vs. 15.9%; P P P = 0.671) in study 2, and 55.4% versus 46.7% ( P = 0.003) in the pooled analysis. A greater percentage of patients treated with nepafenac 0.3% versus vehicle in study 1 and similar percentage in study 2 had a BCVA improvement of ≥15 letters from preoperative baseline through day 90 (77.2% vs. 67.7% [ P = 0.009] and 65.4% vs. 65.9% [ P = 0.888]) and through day 60 (76.2% vs. 64.7% [ P = 0.002] and 68.9% vs. 62.1% [ P = 0.092]). No unanticipated adverse events were observed. Conclusions These studies demonstrated the clinical benefits of nepafenac 0.3% over vehicle in reducing the risk of postoperative ME, with the integrated analysis showing improved BCVA after cataract surgery in patients with diabetic retinopathy, with no unanticipated safety events.

To characterize evolution of macular injury from a high-powered blue handheld laser using multimodal imaging and describe successful surgical treatment.Observational clinical case report.A 17-year-old boy presented with unilateral acute loss of vision with discrete white macular lesions, full-thickness disruption of retinal layers, and hyperreflective material at the fovea on optical coherence tomography caused by exposure to a 445 nm blue-light handheld laser with power up to 2,000 mW characterized as a Class IV laser. The injury evolved into an approximately 950-μm full-thickness macular hole 3 weeks later with visual acuity of 20/400. Vitrectomy and internal limiting membrane peel resulted in anatomic success and final vision at 4 months of 20/25.High-powered lasers can induce significant disruption of retinal layers, inflammatory debris, and full-thickness macular holes with momentary exposure that, despite poor anatomic prognostic factors, can have successful surgical outcomes.

Vitreoretinal surgery procedures demand high precision and have to be performed with limited visualization and access. Using virtual fixtures in conjunction with robotic surgery has the potential to improve the safety and accuracy of these procedures. A cornerstone of many of these virtual fixtures is reconstruction of the retinal surface with respect to the surgical tool, which is difficult to obtain due to the inadequacy of traditional stereo vision techniques in the intact eye. A structured-light technique applied using an actuated handheld instrument has been proposed to combat this problem, but it only provides a reconstruction at the start of the procedure; it cannot update it as the eye moves during surgery. We propose updating the initial estimate of the retinal plane a single point at a time, by continued detection of a laser aiming beam in each camera frame, as in the initial structured-light approach. This paper presents the technique and demonstrates it via experiment.

To report refractive outcomes of scleral-fixated intraocular lens (IOL) implantation with Gore-Tex (W.L. GoreAssociates, Newark, DE) suture and combined pars plana vitrectomy and compare predicted refractive outcomes among 5 IOL power calculation formulas.Retrospective case series.Patients undergoing scleral-fixated IOL implantation with Gore-Tex suture at our institution between January 2015 and June 2018.Comparison of preoperative biometrics with postoperative refraction and calculation of predicted refractive outcome with 5 different IOL formulas.Prediction error and absolute error to compare postoperative refraction with refraction predicted by lens power calculation formulas.Thirty-one eyes of 31 patients were included. All power calculations assumed in-the-bag position of the IOL. The Akreos A060 (BauschLomb, Rochester, NY) was implanted in 23 eyes and the CZ70BD (Alcon, Fort Worth, TX) in 8 eyes, and all lenses were sutured 3 mm behind the limbus. Average postoperative spherical equivalent (SE) was -0.79±0.95 diopters (D). Average prediction error (postoperative SE refraction minus target refraction) was -0.19±0.72 D. Postoperative SE was within 1.0 D of target in 25 of 31 patients (81%) and 2.0 D of target in 31 of 31 patients (100%). The repeated-measures analysis of variance of absolute error by lens power formula was significant (P = 0.012), with Haigis demonstrating greater error. There was no significant difference among Barrett II, Sanders-Retzlaff-Kraff theoretical (SRK/T), Holladay 2, or Hoffer Q.For eyes undergoing pars plana vitrectomy with scleral-sutured IOL implantation, assumption of in-the-bag IOL position when calculating lens power leads to acceptable refractive outcomes. Barrett II, SRK/T, Holladay 2, and Hoffer Q formulas were noninferior to each other.

The interplay of multiple biologic pathways and processes acts in synchrony to repair wounded tissue. Proangiogenic and inflammatory mediators allow enhanced delivery of oxygen and nutrients to repair wounded tissue. Fibrosis is the hallmark feature of wound healing in its final stage. In the eye, subretinal fibrosis, a nonfunctioning mass of fibrotic tissue situated in the subretinal space, is a manifestation of aberrant repair and is the characteristic end-stage subretinal lesion in exudative or neovascular age-related macular degenerative. The subretinal fibrotic lesion is preceded by gradual degeneration of the outer retinal cellular structures, the development of neovascular vessels, inflammation, and retinal tissue damage that culminates into the development of subretinal fibrosis. In this chapter, we will review the pathobiology of exudative age-related macular degeneration (AMD) as it relates to the pathogenesis of its end-stage visually devastating cicatricial lesion: subretinal fibrosis.

PURPOSE: Robot-assisted intraocular microsurgery can improve performance by aiding the surgeon in operating on delicate micron-scale anatomical structures of the eye. In order to account for the eyeball motion that is typical in intraocular surgery, there is a need for fast and accurate algorithms that map the retinal vasculature and localize the retina with respect to the microscope. METHODS: This work extends our previous work by a graph-based SLAM formulation using a sparse incremental smoothing and mapping (iSAM) algorithm. RESULTS: The resulting technique, “EyeSAM,” performs SLAM for intraoperative vitreoretinal surgical use while avoiding spurious duplication of structures as with the previous simpler technique. The technique also yields reduction in average pixel error in the camera motion estimation. CONCLUSIONS: This work provides techniques to improve intraoperative tracking of retinal vasculature by handling loop closures and achieving increased robustness to quick shaky motions and drift due to uncertainties in the motion estimation.

Frequency domain multiplexing (FDM) is a useful for making multiple measurements simultaneously, such as in optical and electromagnetic position trackers. Much interference is periodic (e.g., AC power harmonics), and is rejected well by FDM, but impulse disturbances are also common. Impulses corrupt the entire spectrum for a short period, and are better rejected in the time domain. Nonlinear blanking is a simple way to suppress impulses, but cannot be easily realized when the required dynamic range is large, and problematic noise may be far smaller than the signal. The described multi-rate Kalman filter upsamples the prediction to the input rate so that impulse departures from the predicted signal are easily detected and blanked out. Also, noise levels in unused adjacent channels are used to estimate measurement noise so that the Kalman filter adapts more slowly when noise is high, keeping output noise roughly constant even in the presence of longer noise bursts.

PURPOSE To illustrate spontaneous resolution of macular epiretinal membranes and inactivation of retinal hemangioma exudation after fluorescein potentiated argon laser treatment of bilateral capillary hemangiomas in a patient with a de novo heterozygous deletion in Exon 2 of the von Hippel-Lindau gene. METHODS Interventional case report. RESULTS A 23-year-old man with subjective complaints of blurry vision, photophobia, and glare. On presentation, visual acuity was 20/20 in the right eye and 20/25 in the left eye with metamorphopsia. On the basis of bilateral retinal hemangiomas on clinical examination and characterization with multimodal imaging, a diagnosis of von Hippel-Lindau disease was made. Genetic testing identified a de novo, disease-causing heterozygous deletion in Exon 2 of the von Hippel-Lindau gene. The patient underwent 4 sessions of fluorescein potentiated 532 nm argon green laser treatment directed at retinal hemangiomas. No adverse sequelae of laser treatment were noted. Seven months after the initial presentation, the patient's vision was 20/20 in both eyes with interval resolution of metamorphopsia. There was spontaneous resolution of a macular epiretinal membrane with normalization of the macular retinal microstructure. The retinal hemangiomas in both eyes appeared inactive, and no new lesions were noted. CONCLUSION Fluorescein potentiated argon laser successfully treated bilateral retinal hemangiomas in our patient with von Hippel-Lindau disease. Additional studies to characterize the full clinical potential of fluorescein potentiated argon laser therapy may be warranted.

Purpose Lifitegrast is an integrin antagonist that decreases T-cell–mediated inflammation associated with dry eye disease (DED). We report the results of OPUS-2, a phase III study evaluating the efficacy and safety of lifitegrast compared with placebo for the treatment of DED. Design A 12-week, multicenter, randomized, prospective, double-masked, placebo-controlled clinical trial. Participants Adults aged ≥18 years with use of artificial tears within 30 days, inferior corneal staining score ≥0.5 (0–4 scale), Schirmer tear test (without anesthesia) ≥1 and ≤10 mm, and eye dryness score ≥40 (0–100 visual analogue scale [VAS]). Methods Subjects were randomized 1:1 after 14-day placebo run-in to lifitegrast ophthalmic solution 5.0% or placebo twice daily for 84 days. Main Outcome Measures Co-primary efficacy end points were change, from baseline to day 84, in eye dryness score (VAS, both eyes) and inferior corneal fluorescein staining score in the designated study eye. Secondary end points were change, from baseline to day 84, in ocular discomfort score (0–4 scale) in study eye, eye discomfort score (VAS), total corneal staining score in the study eye, and nasal conjunctival lissamine green staining score (0–4 scale) in the study eye. Treatment-emergent adverse events (TEAEs) were recorded. Results A total of 718 subjects were randomized: placebo, n=360; lifitegrast, n=358 (intent-to-treat population). Lifitegrast-treated subjects experienced greater improvement in eye dryness than placebo-treated subjects (treatment effect, 12.61; 95% confidence interval [CI], 8.51–16.70; P P = 0.6186). There was nominally significant improvement of secondary symptom end points among lifitegrast-treated subjects: ocular discomfort (nominal P = 0.0005) and eye discomfort (nominal, P Conclusions Lifitegrast met the co-primary symptom end point (eye dryness) but not the co-primary sign end point (inferior corneal staining). Secondary end point findings were consistent with this pattern. Most ocular TEAEs were mild to moderate; there were no unexpected TEAEs. Lifitegrast warrants further consideration as a treatment for DED.

A 72-year-old man presented after a single choroidal mass was incidentally detected on fundus examination of his right eye. The patient has a history of multiple myeloma and neuroendocrine thymoma diagnosed 6 and 10 years before presentation, respectively. Fine-needle aspiration biopsy revealed metastatic choroidal carcinoid tumor. The patient was subsequently treated with brachytherapy (iodine-125).

Background and Objective Laser photocoagulation is a mainstay or adjuvant treatment for a variety of common retinal diseases. Automated laser photocoagulation during intraocular surgery has not yet been established. The authors introduce an automated laser photocoagulation system for intraocular surgery, based on a novel handheld instrument. The goals of the system are to enhance accuracy and efficiency and improve safety. Materials and Methods Triple-ring patterns are introduced as a typical arrangement for the treatment of proliferative retinopathy and registered to a preoperative fundus image. In total, 32 target locations are specified along the circumferences of three rings having diameters of 1, 2, and 3 mm, with a burn spacing of 600 μm. Given the initial system calibration, the retinal surface is reconstructed using stereo vision, and the targets specified on the preoperative image are registered with the control system. During automated operation, the laser probe attached to the manipulator of the active handheld instrument is deflected as needed via visual servoing in order to correct the error between the aiming beam and a specified target, regardless of any erroneous handle motion by the surgeon. A constant distance of the laser probe from the retinal surface is maintained in order to yield consistent size of burns and ensure safety during operation. Real-time tracking of anatomical features enables compensation for any movement of the eye. A graphical overlay system within operating microscope provides the surgeon with guidance cues for automated operation. Two retinal surgeons performed automated and manual trials in an artificial model of the eye, with each trial repeated three times. For the automated trials, various targeting thresholds (50–200 μm) were used to automatically trigger laser firing. In manual operation, fixed repetition rates were used, with frequencies of 1.0–2.5 Hz. The power of the 532 nm laser was set at 3.0 W with a duration of 20 ms. After completion of each trial, the speed of operation and placement error of burns were measured. The performance of the automated laser photocoagulation was compared with manual operation, using interpolated data for equivalent firing rates from 1.0 to 1.75 Hz. Results In automated trials, average error increased from 45 ± 27 to 60 ± 37 μm as the targeting threshold varied from 50 to 200 μm, while average firing rate significantly increased from 0.69 to 1.71 Hz. The average error in the manual trials increased from 102 ± 67 to 174 ± 98 μm as firing rate increased from 1.0 to 2.5 Hz. Compared to the manual trials, the average error in the automated trials was reduced by 53.0–56.4%, resulting in statistically significant differences (P ≤ 10−20) for all equivalent frequencies (1.0–1.75 Hz). The depth of the laser tip in the automated trials was consistently maintained within 18 ± 2 μm root-mean-square (RMS) of its initial position, whereas it significantly varied in the manual trials, yielding an error of 296 ± 30 μm RMS. At high firing rates in manual trials, such as at 2.5 Hz, laser photocoagulation is marginally attained, yielding failed burns of 30% over the entire pattern, whereas no failed burns are found in automated trials. Relatively regular burn sizes are attained in the automated trials by the depth servoing of the laser tip, while burn sizes in the manual trials vary considerably. Automated avoidance of blood vessels was also successfully demonstrated, utilizing the retina-tracking feature to identify avoidance zones. Conclusion Automated intraocular laser surgery can improve the accuracy of photocoagulation while ensuring safety during operation. This paper provides an initial demonstration of the technique under reasonably realistic laboratory conditions; development of a clinically applicable system requires further work. Lasers Surg. Med. 47:658–668, 2015. © 2015 Wiley Periodicals, Inc.

Background Peeling procedures in retinal surgery require micron-scale manipulation and control of sub-tactile forces. Methods Hybrid position/force control of an actuated handheld microsurgical instrument is presented as a means for simultaneously improving positioning accuracy and reducing forces to prevent avoidable trauma to tissue. The system response was evaluated, and membrane-peeling trials were performed by four test subjects in both artificial and animal models. Results Maximum force was reduced by 56% in both models compared with position control. No statistically significant effect on procedure duration was observed. Conclusions A hybrid position/force control system has been implemented that successfully attenuates forces and minimizes unwanted excursions during microsurgical procedures such as membrane peeling. Results also suggest that improvements in safety using this technique may be attained without increasing the duration of the procedure. Copyright © 2015 John Wiley & Sons, Ltd.

Purpose This report describes a fulminant infection with Clostridium perfringens after an intravitreal anti-vascular endothelial growth factor injection. Methods This is a retrospective case review. Results Our patient's rapid infection eventually led to enucleation, despite broad-spectrum antibiotic therapy. Conclusion Reporting rare causes and common clinical findings of C. perfringens ocular infection may lead to earlier detection and intervention.

We describe early efforts in design and development of an In-Loop Electromagnetic Tracker (ILEMT), designed to meet the demanding latency and resolution requirements for handheld robotic systems that perform active stabilization of hand motion during microsurgery. The objective is to surpass the best commercial electromagnetic trackers in latency while matching them in root-bandwidth/resolution. The concept is to use frequency-domain multiplexing for fast measurement and high accuracy during rapid motion, and bifrequency dual-path eddy-current compensation (reducing distortion from metals without sacrificing speed). The use of two widely spaced carrier frequencies (e.g., 300 Hz and 10 kHz) enables a particularly simple way of reducing the eddy-current interference caused by nonferrous metals. Previously, metal compatibility has come at the price of reduced measurement speed.

Background Fast and accurate mapping and localization of the retinal vasculature is critical to increasing the effectiveness and clinical utility of robot-assisted intraocular microsurgery such as laser photocoagulation and retinal vessel cannulation. Methods The proposed EyeSLAM algorithm delivers 30 Hz real-time simultaneous localization and mapping of the human retina and vasculature during intraocular surgery, combining fast vessel detection with 2D scan-matching techniques to build and localize a probabilistic map of the vasculature. Results In the harsh imaging environment of retinal surgery with high magnification, quick shaky motions, textureless retina background, variable lighting and tool occlusion, EyeSLAM can map 75% of the vessels within two seconds of initialization and localize the retina in real time with a root mean squared (RMS) error of under 5.0 pixels (translation) and 1° (rotation). Conclusions EyeSLAM robustly provides retinal maps and registration that enable intelligent surgical micromanipulators to aid surgeons in simulated retinal vessel tracing and photocoagulation tasks.

This paper presents robot-aided intraocular laser surgery using a handheld robot known as Micron. The micromanipulator incorporated in Micron enables visual servoing of a laser probe, while maintaining a constant distance of the tool tip from the retinal surface. The comparative study was conducted with various control methods for evaluation of robot-aided intraocular laser surgery.

This paper describes recent work in the development of the In-Loop Electromagnetic Tracker (ILEMT), designed to meet the demanding latency and resolution requirements for active stabilization of hand motion during precision manipulations such as microsurgery. The prototype surpasses the fastest commercial EM trackers by > 4x in root bandwidth/resolution and 2x in latency. The use of two widely spaced carrier frequencies (e.g., 300 Hz and 10 kHz) enables a particularly simple way of reducing the eddy-current interference caused by nonferrous metals present in the workspace. Previously, metal compatibility has only been achieved at a large cost to measurement speed.

Aicardi syndrome is a rare congenital disorder with a classic triad of infantile spasms, chorioretinal lacunae, and agenesis of the corpus callosum. We report the use of fluorescein angiography and spectral domain optical coherence tomography to examine the posterior segment structures in an 8-month-old girl with Aicardi syndrome. Most of the observed features correlated with previously published histopathological findings, but inner nuclear layer cysts have not been previously described. To our knowledge, this is the first study of the tomographic and angiographic chorioretinal features in vivo.

Massive submacular hemorrhage can cause disastrous visual complications. Prompt displacement away from the fovea is desirable in some patients. We describe a novel surgical technique involving subretinal air as a therapeutic adjuvant for massive submacular hemorrhage displacement.

To describe the corticosteroid-sparing success in controlling chronic uveitis in patients treated with TNFα inhibitors.Retrospective longitudinal case series of patients started on infliximab (n = 31) or adalimumab (n = 12) for chronic noninfectious uveitis at a tertiary referral center. The main outcome was corticosteroid-sparing success. Secondary outcomes were sustained control of inflammation regardless of corticosteroid-sparing effect, tapering of concurrent nonbiologic therapy, and discontinuation.Sustained control of inflammation with corticosteroid-sparing success on infliximab and adalimumab, respectively, was achieved in 33.3 and 37.5% at 3 months, 60.7 and 62.5% at 6 months, and 60.9 and 57.1% at 12 months. Median time to this outcome was 98 days for infliximab and 169 days for adalimumab. Six infliximab patients had adverse reactions.Infliximab and adalimumab improve control of ocular inflammation and are successful corticosteroid-sparing agents. However, time to corticosteroid-sparing control of inflammation may take a few months with either agent, and adverse reactions may limit treatment.