Successful Complete Revascularization With PCI Using Super-Low Volume of Contrast Medium in a Patient With Three-Vessel Disease Including 2 Chronic Total Occlusions With Severe Renal Dysfunction.

The most important factor for preventing contrast-induced nephropathy (CIN) during percutaneous coronary intervention (PCI) in patients with severe renal dysfunction is to minimize the contrast volume. Herein, we report a successful case of complete revascularization after 3 separate PCI procedures using a super-low volume of contrast medium in a patient with 3-vessel disease, including two chronic total occlusions (CTOs). A 70-year-old man having exertional angina despite maximal medical therapy was referred to our hospital. He had severe renal dysfunction (estimated glomerular filtration rate 19 mL/minute/1.73 m2). Coronary angiography, in which a total volume of 15 mL (over 3 injections) of contrast medium was used after hydration with normal saline, demonstrated 2 CTOs in the proximal left circumflex artery (LCX) and the proximal right coronary artery (RCA) as well as focal stenosis in the mid left descending artery (LAD). Because the patient refused coronary artery bypass grafting, we opted for revascularization with PCI, divided into 3 procedures. We made full use of microcatheter tip injection and evaluation with intravascular ultrasound and achieved complete revascularization with a total of 31 mL of contrast medium: 9 mL for RCA, 6 mL for LAD, and 16 mL for LCX, without the occurrence of CIN. Additionally, we present tips for performing PCI using super-low contrast medium.

Surgically induced changes in retinal vessel diameter, retinal nerve fibre layer thickness, and the optic disc after 23-gauge pars plana vitrectomy.

The aim of the study is to investigate the retinal vascular calibre, retinal nerve fibre layer's thickness, and optic disc changes in patients after pars plana vitrectomy. We examined 40 eyes in 40 patients who had undergone unilateral pars plana vitrectomy at three time points: prior to surgery, and at 3 and 6 months after the operation. The diameters of central retinal arteries and veins were measured using retinal photographs. The central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) were calculated using the revised Parr-Hubbard formula. Retinal nerve fibre layer thickness was obtained using Stratus optical coherence tomography. The cup-to-disc vertical ratio of the optic disc was evaluated using stereo optic disc photography. There were no significant differences between the eyes of individual patients before the operation. Cup-to-disc vertical ratios of the optic disc were significantly increased 3 and 6 months postoperatively (p < 0.01, p < 0.01), and there was a significant difference between the operative eye and fellow eye at the same time points (p < 0.01, p < 0.01). Changes in CRAE and CRVE in the operative eyes were significantly larger than the fellow eyes 6 months postoperatively (p < 0.01, p < 0.01). The retinal nerve fibre layer thickness showed no significant changes. While there were no changes in retinal nerve fibre layer thickness, vitrectomy induced changes in the cup-to-disc vertical ratio of the optic disc and retinal vessel diameter for at least 6 months after surgery.

Intravitreal bevacizumab and feeder vessel laser treatment for a posteriorly located retinal capillary hemangioma.

Retinal capillary hemangioma (RCH) is strongly associated with von Hippel-Lindau (VHL) disease. Treatment of this sight-threatening condition is often unsatisfactory despite multiple treatment options available. We here describe an interesting case of a 50-year-old male with RCH located in the perifoveal region of the left eye. Subretinal bleed, exudation, and macular edema resulted in progressive deterioration of visual acuity. Fundus photography, fluorescein angiography, and optical coherence tomography (OCT) were used to serially monitor the lesion. After ruling out systemic lesions of VHL disease, the patient was subjected to direct laser photocoagulation of the lesion which resulted in further loss in vision with increase in bleed and exudation. Subsequently, the patient was given 2 monthly intravitreal injections of bevacizumab followed by laser photocoagulation of feeder arteriole. This combination therapy resulted in resolution of exudation, bleed, and macular edema with improvement in visual acuity. Thus, vision-threatening RCH may be safely and effectively treated by means of a combination therapy comprising of intravitreal bevacizumab and feeder vessel treatment.

RETINAL NEOVASCULARIZATION FROM A PATIENT WITH CUTIS MARMORATA TELANGIECTATICA CONGENITA.

PURPOSE: To report a rare case of peripheral retinal neovascularization in a patient diagnosed with cutis marmorata telangiectatica congenita (CMTC). METHODS: Observational case report. RESULTS: A 16-year-old girl was referred to clinic for retinal evaluation. The patient had a clinical diagnosis of CMTC later confirmed by skin biopsy. Examination revealed temporal peripheral retinal sheathing, as well as lattice degeneration in both eyes. Wide-field fluorescein angiogram showed substantive peripheral retinal nonperfusion with evidence of vascular leakage from areas of presumed retinal neovascularization. The patient subsequently had pan retinal photocoagulation laser treatment to each eye without complication. DISCUSSION: Cutis marmorata telangiectatica congenita is a rare vascular condition known to affect multiple organ systems including the eyes. Although ocular manifestations of CMTC are rare, instances of congenital glaucoma, suprachoroidal hemorrhage, and bilateral total retinal detachments resulting in secondary neovascular glaucoma have been reported. Our patient demonstrates the first reported findings of peripheral nonperfusion and retinal neovascularization related to CMTC in a 16-year-old girl. We propose early retinal examination, wide-field fluorescein angiogram, and early pan retinal photocoagulation laser treatment in patients with peripheral nonperfusion and retinal neovascularization from CMTC.

Retinal vessel analyzer measurements of the effect of panretinal photocoagulation on the retinal arteriolar diameter in diabetic retinopathy.

PURPOSE: The purpose of this study was to investigate the effect of panretinal photocoagulation (PRP) on the retinal arteriolar diameter in patients with diabetic retinopathy using a retinal vessel analyzer. METHODS: Ten eyes of 6 consecutive patients with type II diabetes and severe nonproliferative or proliferative diabetic retinopathy were studied prospectively. Measurements of the retinal arteriolar diameter were performed before the first photocoagulation session and after the end of the PRP treatment. RESULTS: Retinal arteriolar diameter before PRP was 131 +/- 15 arbitrary units and decreased to 112 +/- 14 arbitrary units after PRP (P = 0.012). There was a significant vasoconstriction of 13.8% +/- 8.3% following PRP. Mean visual acuity before and after PRP was 0.31 +/- 0.36 logarithm of the minimal angle of resolution and 0.28 +/- 0.30 logarithm of the minimal angle of resolution, respectively (P = 0.68). There was no significant change in mean arterial pressure before and after PRP (P = 0.89). There was no correlation between the visual acuity change or the number of laser burns and the percentage change in the retinal arteriolar diameter (P > 0.1). CONCLUSION: Panretinal photocoagulation has a vasoconstrictive effect on retinal arterioles in patients with severe nonproliferative or proliferative diabetic retinopathy. These results are consistent with an autoregulatory response of the retinal circulation to increased inner retinal oxygen tension after PRP. The retinal vessel analyzer is a fast, accurate, noninvasive, online measuring system for the study of the retinal vascular response to PRP in patients with diabetic retinopathy.

Semiautomated intraocular laser surgery using handheld instruments.

BACKGROUND AND OBJECTIVE: In laser retinal photocoagulation, hundreds of dot-like burns are applied. We introduce a robot-assisted technique to enhance the accuracy and reduce the tedium of the procedure. MATERIALS AND METHODS: Laser burn locations are overlaid on preoperative retinal images using common patterns such as grids. A stereo camera/monitor setup registers and displays the planned burn locations overlaid on real-time video. Using an active handheld micromanipulator, a 7 x 7 grid of burns spaced 650 microm apart is applied to both paper slides and porcine retina in vitro using 30 milliseconds laser pulses at 532 nm. Two scenarios were tested: unaided, in which the micromanipulator is inert and the laser fires at a fixed frequency, and aided, in which the micromanipulator actively targets burn locations and the laser fires automatically upon target acquisition. Error is defined as the distance from the center of the observed burn mark to the preoperatively selected target location. RESULTS: An experienced retinal surgeon performed trials with and without robotic assistance, on both paper slides and porcine retina in vitro. In the paper slide experiments at an unaided laser repeat rate of 0.5 Hz, error was 125+/-62 microm with robotic assistance and 149+/-76 microm without (P < 0.005), and trial duration was 70+/-8 seconds with robotic assistance and 97+/-7 seconds without (P < 0.005). At a repeat rate of 1.0 Hz, error was 129+/-69 microm with robotic assistance and 166+/-91 microm without (P < 0.005), and trial duration was 26+/-4 seconds with robotic assistance and 47+/-1 seconds without (P < 0.005). At a repeat rate of 2.0 Hz on porcine retinal tissue, error was 123+/-69 microm with robotic assistance and 203+/-104 microm without (P < 0.005). CONCLUSION: Robotic assistance can increase the accuracy of laser photocoagulation while reducing the duration of the operation.

Early laser photocoagulation for extensive retinal avascularity in infants with incontinentia pigmenti.

PURPOSE: To describe the clinical features and treatment outcomes of severe retinopathy in eyes with incontinentia pigmenti (IP) of infants within a few months of birth. STUDY DESIGN: Retrospective clinical study. METHODS: Six eyes of three patients (6-day-old girl, 5-month-old girl, and 14-day-old boy) with IP were examined and treated under general anesthesia. Ophthalmologic examinations were performed including images from wide-angle fluorescein angiography (FA), swept-source optical coherence tomography (OCT), and OCT angiography (OCTA). RESULTS: Ophthalmoscopy showed prominent vascular tortuosity in five eyes, retinal hemorrhages in four eyes, and incomplete vascular development in two eyes. FA showed extensive avascularity including the posterior pole of the retina in all cases except one eye. Prompt and intensive laser photocoagulation stabilized the pre-proliferative severe retinopathy in five eyes; however, foveal structure and vessel anomalies were detected in three of six eyes by OCT and two of five eyes by OCTA. CONCLUSION: Severe retinopathy in the neonatal period and infancy was present not only in the periphery but also in the posterior pole including the fovea, which might be related to retinal vascular maldevelopment. It is, therefore, recommended that wide-angle fundus FA examination be performed in the early postnatal period to detect early signs of severe retinopathy in infants with IP.

Robot-assisted vitreoretinal surgery: development of a prototype and feasibility studies in an animal model.

PURPOSE: To develop a prototype robotic system designed to assist vitreoretinal surgery and to evaluate its accuracy and maneuverability. DESIGN: Experimental study. PARTICIPANTS: This study used harvested porcine eyes. METHODS: After development of a prototype robotic system, pointing accuracy tests of the system were performed on graph paper and in harvested porcine eyes. The average maximal deviation from the aiming point to the actual position of the tip of the instrument was compared between manually conducted procedures and those conducted with robotic assistance. The feasibility of creating posterior vitreous detachment (PVD), retinal vessel sheathotomy (RVS), and retinal vessel microcannulation also were evaluated in porcine eye models, and the success rates of 4 consecutive attempts for each kind of procedure were evaluated. MAIN OUTCOME MEASURES: The average maximum deviation in pointing accuracy tests both on graph paper and in animal eye models was a main outcome measure. The success rate of making PVD, RVS, and retinal vessel microcannulation was the other primary outcome measure. RESULTS: The pointing accuracy was superior with robotic assistance both on graph paper (327.0 microm vs. 32.3 microm) and in animal eye models (140.8 microm vs. 33.5 microm). Creating PVD, RVS, and retinal vessel microcannulation was feasible in 4 of 4 attempts, 4 of 4 attempts, and 2 of 4 attempts, respectively. The 2 failures in microcannulation were considered to be the result of difficulty in visual differentiation between the retinal vessel and retina in harvested porcine eyes. CONCLUSIONS: Improved accuracy and desirable feasibility of a prototype robotic system to assist vitreoretinal surgery were shown in this study. Research for wider implementation of robot-assisted surgery should be continued; there are some hurdles to overcome.

Vascular abnormalities in aggressive posterior retinopathy of prematurity detected by fluorescein angiography.

PURPOSE: To evaluate fluorescein angiography (FA) in eyes with aggressive posterior retinopathy of prematurity (AP-ROP). DESIGN: Retrospective, nonrandomized case series. PARTICIPANTS: Three patients (6 eyes) with AP-ROP. METHODS: Three patients (6 eyes) diagnosed with AP-ROP during ROP screening between July 2007 and July 2008 were included in this study. Fundus photographs and FA were obtained before and after laser and surgical treatment using a wide-field digital pediatric imaging system. MAIN OUTCOME MEASURES: Fluorescein angiography and fundus photographs. RESULTS: At the initial stage of AP-ROP, FA showed vascular abnormalities, including capillary nonperfusion throughout the vascularized retina, shunting in the vascularized retina, a circumferential demarcation line, and limited vessel development, which was difficult to identify only by ophthalmoscopy. After treatment, FA showed poorly developed retinal vessels, including 4 small major vessels without an arcade pattern, small macular vessels, an inhomogeneous capillary bed, and absence of a capillary-free zone in the fovea. CONCLUSIONS: Capillary bed loss throughout the vascularized posterior retina is characteristic of AP-ROP and may exacerbate retinopathy.

[Leber miliary aneurysms--a case report]. / Tetniaki prosówkowate Lebera--opis przypadku.

We present a case of 21 years old male with significant unilateral decrease of vision. Ophthalmoscopic examination revealed distinct macular edema and peripheral retinal edema. Fluorescein angiography showed peripheral retinal telangiectasia, arteriolal and venous shunts and large areas of hypoperfusion. Base on that picture, diagnosis of miliary Leber aneurysms was made. It followed by laser photocoagulation of retina: macular GRID and peripheral scatter. After 4 months return of normal visual acuity was noted, as well as lack of retinal edema in fluorescein angiography.

Design and evaluation of a new bioelectrical impedance sensor for micro-surgery: application to retinal vein cannulation.

PURPOSE: Nowadays, millions of people suffer from retinal vein occlusion, a blind-making eye disease. No curative treatment currently exists for this vascular disorder. However, a promising treatment consists in injecting a thrombolytic drug directly inside the affected retinal vessel. Successfully puncturing miniature vessels with diameters between 50 and 400 [Formula: see text] remains a real challenge, amongst others due to human hand tremor, poor visualisation and depth perception. As a consequence, there is a significant risk of double-puncturing the targeted vessel. Sub-surfacic injection of thrombolytic agent could potentially lead to severe retinal damage. METHODS: A new bio-impedance sensor has been developed to visually display the instant of vessel puncture. The physical working principle of the sensor has been analysed, and a representative electrical model has been derived. Based on this model, the main design parameters were derived to maximise the sensor sensitivity. A detailed characterisation and experimental validation of this concept were conducted. RESULTS: Stable, repeatable and robust impedance measurements were obtained. In an experimental campaign, 35 puncture attempts on ex vivo pig eyes vessels were conducted. A confusion matrix shows a detection accuracy of 80% if there is a puncture, a double puncture or no puncture. The 20% of inaccuracy most probably comes from the limitations of the employed eye model and the experimental conditions. CONCLUSIONS: The developed bio-impedance sensor has shown great promise to help in avoiding double punctures when cannulating retinal veins. Compared to other puncture detection methods, the proposed sensor is simple and therefore potentially more affordable. Future research will include validation in an in vivo situation involving vitreoretinal surgeons.

EyeSAM: graph-based localization and mapping of retinal vasculature during intraocular microsurgery.

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.

Optical coherence tomography angiography features in patients with idiopathic full-thickness macular hole, before and after surgical treatment.

PURPOSE: To present optical coherence tomography (OCT) angiography features in patients with idiopathic full-thickness macular hole before and after vitrectomy. STUDY DESIGN: Prospective case series study. MATERIALS AND METHODS: Patients presenting with an idiopathic full-thickness macular hole (IMH) who underwent posterior vitrectomy with internal limiting membrane peeling and gas tamponade were included in the study. En face OCT and OCT angiography (OCTA) was performed pre- and postoperatively using 3×3 mm scans (Optovue, XR Avanti). Foveal avascular zone (FAZ) area, macular hole size (MHS), central retinal thickness (CRT), macular parafoveal choriocapillary flow area (MCFA), and fovea vessel density (FVDS) were measured and assessed using OCTA. Best-corrected visual acuity (BCVA) was examined before and 3 months after surgery. RESULTS: Twenty-eight eyes of 28 patients were included in the study. The mean age of patient group was 68.28 years. The hole was closed in all eyes after the initial surgery. OCTA showed enlargement of FAZ and increased CRT in foveal area. Mean preoperative FAZ area was 0.39±0.07 mm2. En face images of the middle retina showed a range of preoperative cystic patterns surrounding the hole. BCVA was improved from 0.1±0.11 preoperatively to 0.42±0.17 postoperatively. Mean FAZ area was reduced to 0.24±0.07 mm2 postoperatively with resolution of macular hole and adjacent cystic areas. Mean CRT was reduced from 396±62.6 µm pre-operatively to 272±30.7 µm postoperatively. After vitrectomy, the parafoveal choriocapillary flow area and FVDS of IMH eyes increased compared with the preoperative measurements. CONCLUSION: Quantitative evaluation of vascular and morphological changes following IMH surgery using OCTA shows the potential for recovery due to vascular and neuronal plasticity. OCTA showing vascular changes and their quantitative characteristics might be a useful tool for the assessment of macular holes before and after surgical treatment.

Adult Coats' Disease, Dubin-Johnson Syndrome, and the Search for Targeted Therapies.

Coats' disease is nonhereditary retinal vascular disorder characterized by telangiectatic retinal vessels with prominent aneurysmal changes and exudation. A conclusive etiology has not yet been determined. In this retrospective case report and literature review, a 64-year-old male with Dubin-Johnson syndrome presented with unilateral retinal vascular changes and exudation consistent with a diagnosis of adult Coats' disease. The authors conclude that patients with Dubin-Johnson syndrome carry mutations in a multidrug resistance associated protein (MRP). MRPs are also expressed in the retina, retinal pigment epithelium, and vascular endothelium, where they export toxins and metabolites, and may serve as a therapeutic target. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:318-321.].

Pathologic roles of prorenin and (pro)renin receptor in the eye.

Recent reports indicated that tissue renin-angiotensin system (RAS) was upregulated and angiotensin II type 1 receptor signaling plays crucial roles in ocular inflammation and neovascularization; however, the precise mechanism for activating tissue RAS had not been defined until recently. (Pro)renin receptor, a recently identified molecule existing in the major organs but not in the circulation, has attracted growing attention as an activator of tissue RAS. When the handle region of the prorenin prosegment binds to (pro)renin receptor, prorenin undergoes a conformational change to its enzymatically active state without the conventional proteolysis of the prorenin prosegment. Systemic treatment with a peptide with the structure of the handle region (handle region peptide; HRP), which competitively binds to (pro)renin receptor as a decoy peptide and inhibit the nonproteolytic activation of prorenin, resulted in the suppression of retinal inflammation and neovascularizaion in the rodent models. Retinal expression of RAS-related inflammatory and angiogenic molecules, such as intercellular adhesion molecule-1, monocyte chemotactic protein-1, and vascular endothelial growth factor, was also suppressed with application of HRP. These findings demonstrate that nonproteolytically activated prorenin plays a significant role in the ocular inflammation and neovascularization.

Subthreshold diode micropulse photocoagulation for the treatment of chronic central serous chorioretinopathy with juxtafoveal leakage.

PURPOSE: To report the visual and clinical outcomes of subthreshold diode micropulse (SDM) laser photocoagulation for chronic idiopathic central serous chorioretinopathy (ICSC) with juxtafoveal leakage. DESIGN: Prospective, noncomparative, interventional case series. PARTICIPANTS: Twenty-six eyes in 25 patients with persistent ICSC and juxtafoveal leakage longer than 4 months' duration. METHODS: All eyes were assigned to SDM photocoagulation. Eyes were divided into 3 groups based on the findings of fluorescein angiography. Groups 1 and 2 were those patients with source leakage without and with associated retinal pigment epithelial atrophy (RPE), respectively, whereas group 3 consisted of patients with diffuse RPE decompensation with indeterminate source leakage. All patients were followed-up for at least 6 months. MAIN OUTCOME MEASURES: The preoperative and postoperative best-corrected visual acuity, number of sessions of SDM photocoagulation, foveal thickness, and resolution of subretinal fluid (SRF) evaluated by ocular coherence tomography (OCT) were recorded. Patients also were tested for the presence or absence of laser-related scotoma with Amsler grid screening. RESULTS: Groups 1, 2, and 3 consisted of, respectively, 6, 9, and 11 eyes. In group 1, all patients had total SRF resorption after 1 session of SDM photocoagulation. Eight eyes in group 2 had total SRF resorption after 1 to 3 sessions of SMD laser, whereas 1 patient had persistent SRF. In group 3, only 5 eyes had SRF resorption at the end of the follow-up, and the other 6 eyes needed photodynamic therapy for final SRF resorption. At the end of follow-up, the average preoperative foveal thickness was reduced by more than half of its original thickness. A gain of visual acuity of 3 lines or more was achieved in 15 eyes (57.7%), and a gain of between 1 and 3 lines was achieved in 6 eyes (23.1%). CONCLUSIONS: Subthreshold diode laser is effective in the treatment of ICSC with point source leakage. However, for eyes with diffuse leakage, a less favorable response was noted. A multicenter, randomized clinical trial is needed to ascertain the real efficacy and the appropriate settings of SMD for chronic ICSC. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Sensitivity of Cross-Trained Deep CNNs for Retinal Vessel Extraction.

Automatic segmentation of vascular network is a critical step in quantitatively characterizing vessel remodeling in retinal images and other tissues. We proposed a deep learning architecture consists of 14 layers to extract blood vessels in fundoscopy images for the popular standard datasets DRIVE and STARE. Experimental results show that our CNN characterized by superior identifying for the foreground vessel regions. It produces results with sensitivity higher by 10% than other methods when trained by the same data set and more than 1% with cross training (trained on DRIVE, tested with STARE and vice versa). Further, our results have better accuracy $> 0 .95$% compared to state of the art algorithms.

Fluorescein Angiographic Abnormalities in the Contralateral Eye with Normal Fundus in Children with Unilateral Coats' Disease.

PURPOSE: We report the detection of peripheral retinal vascular abnormalities in the fellow eye with normal fundus in children with unilateral Coats' disease. METHODS: The clinical records of patients diagnosed with Coats' disease were retrospectively reviewed. We recorded the subjects' characteristics and obtained fundus photography and fluorescein angiography (FA) images. The main outcome measure was peripheral vascular abnormalities in the contralateral eye with normal fundus in children with unilateral Coats' disease, observed with FA. RESULTS: Out of 47 patients with Coats' disease, two (4.3%) were diagnosed with clinically bilateral Coats' disease. Of the 45 patients with presumed unilateral Coats' disease, four (8.9%) had bilateral abnormal peripheral vasculature in FA. The mean age of these four patients was 6.4 ± 5.4 years (range, 1 to 14 years), and three patients were male (75%). All four had peripheral retinal nonperfusion, and two (50%) received laser photocoagulation due to peripheral leakage with telangiectatic vessels. CONCLUSIONS: Coats' disease may more often be a bilateral disease with asymmetry than previously thought. Patients with Coats' disease should undergo careful examination of the fellow eye with FA in order to detect and treat vascular abnormalities that are not visible clinically.

Recurrent vitreous hemorrhage secondary to retinal vessel avulsion.

Spontaneous vitreous hemorrhage is a rare entity, present in 7 out of 100,000 inhabitants. It is associated with different pathologies; however, it is rarely reported to be caused by retinal vessel avulsion syndrome. In the present manuscript, we report a case of avulsion of retinal vessels associated with recurrent vitreous hemorrhage managed, at first, by photocoagulation, but due to the several recurrence of bleeding, the patient went into surgical management.