Clinical Analysis of 42 Cases of Ocular Ischemic Syndrome

Radiation retinopathy vs. ocular ischemic syndrome: how to reach the diagnosis?

We present a case of diagnostic interest; we present the differential diagnosis and the complementary tests necessary to reach it, in addition to highlighting the importance of a correct collection of background and clinical history. A 54-year-old woman with a history of carcinoma of the floor of the mouth treated with radiotherapy and chemotherapy develops ischemic retinopathy. It was necessary to perform a systemic study and differential diagnosis with entities such as ocular ischemic syndrome and radiation retinopathy, due to the similarity in the clinical findings found. Radiation retinopathy should be ruled out in any patient with visual impairment and a history of radiotherapy treatment. A broad differential diagnosis and systemic study are required to rule out entities such as ocular ischemic syndrome and diabetic retinopathy, in addition to early treatment to avoid possible complications.

Comparison of Ophthalmic Artery Morphological Characteristics and Retinal Vessel Diameter for Identifying Ocular Ischemic Syndrome

Purpose

To investigate the morphological characteristics of the ophthalmic artery (OA) and retinal vessels in ocular ischemic syndrome (OIS) and to compare their ability to identify OIS.

Methods

This cross-sectional observational study included 21 patients with unilateral OIS and 17 controls matched for age, sex, degree of internal carotid artery (ICA) stenosis, and cerebral collateral patency. This study used a three-dimensional reconstruction based on computed tomographic angiography to measure the morphological characteristics of the OA and the ICA. Quantitative measurements of retinal vessel diameter were performed using the Integrative Vessel Analysis software. Receiver operating characteristic (ROC) curve analysis was performed to assess the ability of the OA diameter and the central retinal artery equivalent (CRAE) to identify OIS.

Results

The diameter of the OA (odds ratio = 0.001; P = 0.001) and the CRAE (odds ratio = 0.951; P = 0.028) were significantly associated with the presence of OIS after adjusting for age, sex, and the degree of the ICA stenosis. The areas under the curve for the OA diameter and the CRAE were, respectively, 0.871 (P < 0.001) and 0.744 (P = 0.017) according to the ROC curves analysis.

Conclusions

The OA diameter measurement identified OIS better than CRAE measurement. The OA may reflect the changes in ocular blood supply in patients with OIS earlier than retinal vessels. The OA of eyes with OIS may undergo arterial wall remodeling, leading to a decrease in OA diameter and further reduction in blood flow.

Blood flow perfusion in visual pathway detected by arterial spin labeling magnetic resonance imaging for differential diagnosis of ocular ischemic syndrome

Background

Ocular ischemic syndrome (OIS), attributable to chronic hypoperfusion caused by marked carotid stenosis, is one of the important factors that cause ocular neurodegenerative diseases such as optic atrophy. The current study aimed to detect blood flow perfusion in a visual pathway by arterial spin labeling (ASL) and magnetic resonance imaging (MRI) for the differential diagnosis of OIS.

Methods

This diagnostic, cross-sectional study at a single institution was performed to detect blood flow perfusion in a visual pathway based on 3D pseudocontinuous ASL (3D-pCASL) using 3.0T MRI. A total of 91 participants (91 eyes) consisting of 30 eyes with OIS and 61 eyes with noncarotid artery stenosis-related retinal vascular diseases (39 eyes with diabetic retinopathy and 22 eyes with high myopic retinopathy) were consecutively included. Blood flow perfusion values in visual pathways derived from regions of interest in ASL images, including the retinal-choroidal complex, the intraorbital segments of the optic nerve, the tractus optics, and the visual center, were obtained and compared with arm-retinal circulation time and retinal circulation time derived from fundus fluorescein angiography (FFA). Receiver operating characteristic (ROC) curve analyses and the intraclass correlation coefficient (ICC) were performed to evaluate the accuracy and consistency.

Results

Patients with OIS had the lowest blood flow perfusion values in the visual pathway (all p < 0.05). The relative intraorbital segments of optic nerve blood flow values at post-labeling delays (PLDs) of 1.5 s (area under the curve, AUC = 0.832) and the relative retinal-choroidal complex blood flow values at PLDs of 2.5 s (AUC = 0.805) were effective for the differential diagnosis of OIS. The ICC of the blood flow values derived from the retinal-choroidal complex and the intraorbital segments of the optic nerve between the two observers showed satisfactory concordance (all ICC > 0.932, p < 0.001). The adverse reaction rates of ASL and FFA were 2.20 and 3.30%, respectively.

Conclusion

3D-pCASL showed that the participants with OIS had lower blood flow perfusion values in the visual pathway, which presented satisfactory accuracy, reproducibility, and safety. It is a noninvasive and comprehensive differential diagnostic tool to assess blood flow perfusion in a visual pathway for the differential diagnosis of OIS.

The mechanism and therapeutic strategies for neovascular glaucoma secondary to diabetic retinopathy

Neovascular glaucoma (NVG) is a devastating secondary glaucoma characterized by the appearance of neovascular over the iris and the proliferation of fibrovascular tissue in the anterior chamber angle. Proliferative diabetic retinopathy (PDR) is one of the leading causes of NVG. Currently increasing diabetes population drive the prevalence rate of NVG into a fast-rising lane. The pathogenesis underlying NVG makes it refractory to routine management for other types of glaucoma in clinical practice. The combination of panretinal photocoagulation (PRP), anti-vascular endothelial growth factor (VEGF) injections, anti-glaucoma drugs, surgical intervention as well as blood glucose control is needed. Early diagnosis and aggressive treatment in time are crucial in halting the neovascularization process and preserving vision. This review provides an overview of NVG secondary to diabetic retinopathy (DR), including the epidemiology, pathogenesis and management, so as to provide a better understanding as well as potential therapeutic strategies for future treatment.

An Ocular Chameleon

Patients presenting with transient visual loss is common in emergency departments. Neurologists, ophthalmologists and emergency care physicians may be called upon to evaluate such patients. Monocular visual loss should be differentiated from the binocular involvement as the oetologies, investigations and management of such patients differ considerably. We report a case of monocular visual loss that involved predominantly one eye but affected the other side independently, albeit less frequently. A meticulous history, thorough general, neurological and ophthalmological examinations are necessary in such patients to identify the cause and to treat appropriately. Ocular ischemic syndrome (OIS) is due to chronic hypoperfusion of the structures supplied by ophthalmic artery leading to monocular visual loss. Stenosis of the ipsilateral internal carotid artery from a variety of causes is the main underlying mechanism. The first case of OIS was reported by Hedges in 1963 and the term was coined later by Barry and Magargal. Ocular ischemic syndrome is an important differential diagnosis to consider especially in older people and those with vascular risk factors. An overview of important differential diagnosis, clinical features and treatment of OIC are discussed in this article. A multidisciplinary team is optimal for the management of ocular ischemic syndrome.

A review of neovascular glaucoma. Etiopathogenesis and treatment

Neovascular glaucoma (NVG) is a type of secondary glaucoma, refractory to treatment, often incurable, with very poor visual prognosis. It is characterized by the appearance of new vessels over the iris and iridocorneal angle and frequently associates the presence of a fibrovascular membrane which limits the aqueous humor outflow from the anterior chamber. The most common causes of NVG are: central retinal vein occlusion, proliferative diabetic retinopathy, and ocular ischemic syndrome. Once the gonioscopy developed as a part of clinical examination, it became possible to visualize the new vessels of the anterior segment of the eye in early stages and to understand the mechanisms of increased intraocular pressure (IOP), including narrowing and closing of the iridocorneal angle. Also, the modern imaging techniques, such as optical coherence tomography angiography and fluorescein angiography became indispensable for the clinician. Thus, an early diagnosis, followed by starting an appropriate therapy: panretinal photocoagulation or administration of anti-VEGF drugs, with or without hypotensive ocular therapy, allows the preservation of visual functions for patient's better quality of life. However, one or more surgeries will often be required, especially in the advanced stages of the disease, which do not respond to drug therapy. Managing the NVG we should aim to: 1) reduce ocular ischemia and treat its underlying cause, 2) reduce elevated IOP, once installed and 3) control the inflammatory process. Anyway, the best treatment is prevention, so we must be very attentive at patients with risk factors for developing the NVG. Abbreviations: NVG = neovascular glaucoma, ICA = iridocorneal angle, IOP = intraocular pressure, TM = trabecular meshwork, AH = aqueous humor, AC = anterior chamber, PRP = panretinal photocoagulation, VEGF = vascular endothelial growing factor, Anti-VEGF = anti- vascular endothelial growing factor, PAS = peripheral anterior synechiae, CRVO = central retinal vein occlusion, PDR = proliferative diabetic retinopathy, DR = diabetic retinopathy, OIS = ocular ischemic syndrome, CRAO = central retinal artery occlusion, ROP = retinopathy of prematurity, FEVR = familial exudative vitreoretinopathy, PVR = proliferative vitreoretinopathy, MMPs = matrix metalloproteinases, VEGFR = vascular endothelial growing factor receptor, PDGF = platelet-derived growth factor, PIGF = placental growth factor, NRP = neuropilins, HIF = hypoxia-inducible factor, SDF1 = stromal cell-derived factor 1, DDL4 = delta like ligand 4, NICD = Notch intracellular domain, TIMMPs = tissue inhibitors of matrix metalloproteinases, ANGPT = angiopoietin, Tie 2 = tyrosine-protein kinase receptor for angiopoietins, IGF-1 = insulin-like growth factor 1, RPE = retinal pigment epithelium, IL = interleukin, TNF = tumor necrosis factor, bFGF = basic fibroblast growth factor, TGF = transforming growth factor, HGF = hepatocyte growth factor, TNFR 2 = tumor necrosis factor receptor 2, OIR = oxygen induced retinopathy, NVI = neovascularization of the iris, NVA = neovascularization of the iridocorneal angle, FA = fluorescein angiography, RAPD = relative afferent pupillary defect, CNP = capillary non-perfusion, NVE = neovascularization elsewhere in the retina, NVD = neovascularization of the optic disc, FFA = fundus fluorescein angiography, OCTA = optical coherence tomography angiography, B-scan US = B-scan ocular ultrasound, AS-OCT = anterior segment optical coherence tomography, ARC = anterior retinal cryotherapy, FDA = food and drug administration, United States of America, BVZ = bevacizumab, RBZ = ranibizumab, AFB = aflibercept, AMD/ ARMD = age related macular degeneration, DME = diabetic macular edema, GDDs = glaucoma drainage devices, MMC = mitomycin C, 5-FU = 5-fluorouracil, AGV = Ahmed glaucoma valve, AADI = Aurolab aqueous drainage implant, MIGS = minimally invasive glaucoma surgery, BCVA = best corrected visual acuity, TVT = Tube versus Trabeculectomy study, MPC = micro-pulse cyclophotocoagulation.

Utility of Doppler ultrasound for the study of ocular vascular disease

Ocular vascular problems represent an emerging pathology within the activity of the internist. Ocular ultrasound is a widely used technique to evaluate a variety of eye conditions. Specifically, Doppler ultrasound of the ophthalmic vessels has become a very useful tool in diagnosing various eye diseases. Doppler ultrasound allows for examining blood flow in the eye even in the presence of eye opacities that impede viewing the posterior segment of the eye. In this review, we describe the principles and techniques of an ocular vascular Doppler ultrasound examination in clinical practice and provide a general approach to the ultrasound characteristics of the most important vascular eye disorders for internists. These include central retinal artery and vein occlusions, chronic retinal ischemic syndrome, anterior optic ischemic neuropathy, and diabetic retinopathy.

Neovascular glaucoma - A review

Neovascular glaucoma (NVG) is a sight-threatening secondary glaucoma characterized by appearance of new vessels over the iris and proliferation of fibrovascular tissue in the anterior chamber angle. Retinal ischemia is the common driving factor and common causes are central retinal vein occlusion, proliferative diabetic retinopathy, and ocular ischemic syndrome. The current rise in the prevalence of NVG is partly related to increase in people with diabetes. A high index of suspicion and a thorough anterior segment evaluation to identify the early new vessels on the iris surface or angle are essential for early diagnosis of NVG. With newer imaging modalities such as the optical coherence tomography angiography and newer treatment options such as the anti-vascular endothelial growth factor, it is possible to detect retinal ischemia early, tailor appropriate treatment, monitor disease progression, and treatment response. The management strategies are aimed at reducing the posterior segment ischemia, reduce the neovascular drive, and control the elevated intraocular pressure. This review summarizes the causes, pathogenesis, and differential diagnoses of NVG, and the management guidelines. We also propose a treatment algorithm of neovascular glaucoma.

Usefulness of orbital colour Doppler ultrasound in vascular-related monocular vision loss

Acute, painless, monocular vision loss (APMVL) usually has a vascular aetiology. We conducted a prospective observational study from 2011 to 2018 to analyse the added value of colour Doppler imaging to assess orbital vessel blood flow in the diagnosis of APMVL. The study included 67 patients (39 [58.2%] men; mean age, 65.9 years [SD 13.7]) with APMVL evaluated at the Neurosonology Laboratory within the first 5 days of symptom onset, who were classified as having either transient or persistent monocular blindness. The blood flow in the ophthalmic and central retinal arteries was assessed using colour Doppler ultrasound with a linear 7.5-MHz transducer. Thirty-three (49.3%) patients presented transient monocular blindness, with reduced blood flow in either the ophthalmic or central retinal artery. The group with persistent vision loss included 24 cases of central retinal artery occlusion (CRAO) and 10 cases of ischaemic optic neuropathy (35.8% and 14.9%, respectively, of the total sample). These patients were older and had a higher prevalence of hypertension and mild carotid atherosclerosis. Orbital colour Doppler ultrasound (OCDUS) clarified the mechanism/cause of the ischaemia in 11 (16.4%) patients and showed abnormal flow in 46 (68.7%) patients, confirming the vascular origin in 19 (57.6%) of the transient monocular blindness cases. Lower peak systolic velocity was observed in patients with CRAO (p < 0.001), and a velocity < 10 cm/s in the central retinal artery was independently associated with the diagnosis of CRAO. OCDUS can be helpful in confirming the vascular cause and identifying the aetiology of APMVL.

Ocular adverse events associated with immune checkpoint inhibitors: a novel multidisciplinary management algorithm

Ocular immune-related adverse events (IrAEs) associated with use of checkpoint inhibitors (CPIs) in cancer therapeutics are relatively rare, occurring in approximately 1% of treated patients. Recognition and early intervention are essential because the degree of tissue damage may be disproportionate to the symptoms, and lack of appropriate treatment risks permanent loss of vision. International guidelines on managing ocular IrAEs provide limited advice only. Importantly, local interventions can be effective and may avoid the need for systemic corticosteroids, thereby permitting the continuation of CPIs. We present a single institution case series of eight affected patients managed by our multidisciplinary team. Consistent with previously published series and case reports, we identified anterior uveitis as the most common ocular IrAE associated with CPIs requiring intervention. Based on our experience, as well as published guidance, we generated a simple algorithm to assist clinicians efficiently manage patients developing ocular symptoms during treatment with CPIs. In addition, we make recommendations for optimising treatment of uveitis and address implications for ongoing CPI therapy.

Effects of Selenium and Melatonin on Ocular Ischemic Syndrome

Purpose

To determine the effects of selenium, melatonin, and selenium + melatonin administered for one month on anterior chamber (AC) malondialdehyde (MDA) and AC glutathione (GSH) levels in patients with ocular ischemic syndrome.

Materials and Methods

Thirty-five patients were included in the study. Study groups were formed as follows: (1) control group, (2) ischemia group, (3) selenium + ischemia group, (4) melatonin + ischemia group, and (5) selenium + melatonin + ischemia group. AC samples were obtained. MDA and GSH levels in AC samples were evaluated.

Results

MDA levels were significantly increased in ischemia groups. Selenium and melatonin supplementation resulted in reduction of MDA levels and significant increase in GSH values.

Discussion

Increased lipid peroxidation associated with ischemia of the anterior segment has been prevented by selenium and melatonin supplementation. This trial is registered with ClinicalTrials.gov NCT04005222.

Significant changes of the choroid in patients with ocular ischemic syndrome and symptomatic carotid artery stenosis

Purpose

To evaluated the changes in choroidal vasculature in patients with ocular ischemic syndrome (OIS) and in the ipsilateral eyes of patients with symptomatic carotid artery stenosis (CAS)

Method

A total of 50 patients (15 patients with OIS, 10 patients with symptomatic CAS, 25 patients of age-and sex-matched control group) were included, and the medical records were retrospectively reviewed. The mean subfoveal choroidal thickness (SFCT) of each eye was measured, and binary images of the choroid were evaluated to compare the mean choroidal area and the luminal area.

Results

The mean SFCT was 170.5±75.3 μm in the eyes with OIS, 154.8±62.9 μm in the ipsilateral eyes with symptomatic CAS, and 277.5±73.2 μm in the right eyes of the control group patients (P<0.001). The mean choroidal area was 494,478.6±181,846.2 μm2 in the eyes with OIS, 453,750.0±196,725.8 μm2 in the ipsilateral eyes with symptomatic CAS, and 720,520±281,319.5 μm2 in the control group eyes (P = 0.036). The mean luminal area was 333,185.7±112,665.9 μm2 in the eyes with OIS, 313,983.3±132,032.1 μm2 in the ipsilateral eyes with symptomatic CAS, and 480,325.0±185,112.6 μm2 in the control group eyes (P = 0.046). The mean SFCT, mean choroidal area, and mean luminal area were significantly smaller in the eyes with OIS (P = 0.017, P = 0.005, and P = 0.004, respectively), and those with symptomatic CAS (P = 0.020, P = 0.016, and P = 0.021, respectively) than in the unaffected contralateral eyes. There were no significant differences between the eyes in the control group (P = 0.984, P = 284, and P = 0.413, respectively).

Conclusion

The mean SFCT, mean choroidal area, and mean luminal area were significantly thinner in the eyes with OIS and the ipsilateral eyes with symptomatic CAS, compared with the control group eyes. The eyes with OIS and those with symptomatic CAS had significantly thinner SFCT, and smaller choroidal area and luminal area than the unaffected contralateral eyes. Choroid may reflect the vascular status of the carotid artery, indicated by choroidal thinning and decreasing choroidal area, especially luminal area.