Treatment options for central retinal artery occlusion

Update on central retinal artery occlusion

The medical condition referred to as "central retinal artery occlusion" (CRAO) was first documented by Albrecht von Graefe in 1859. Subsequently, CRAO has consistently been identified as a serious medical condition that leads to substantial visual impairment. Furthermore, it is correlated with vascular complications that have the potential to affect crucial organs such as the brain and heart. A considerable amount of research has been extensively published on the various aspects of this topic, which is marked by notable debates and misconceptions, especially regarding its management and outcomes. The primary aim of this review article is to analyze the latest developments in the understanding of CRAO, which includes its causes, techniques for retinal imaging, systemic evaluation, and therapeutic strategies, such as vitrectomy. This review article offers readers a comprehensive learning experience to gain knowledge on the fundamental principles and recent advancements in CRAO.

The Spectrum of Isolated Retinal Artery Occlusion Secondary to Giant Cell Arteritis

We systematically reviewed the literature to investigate the clinical features of isolated arteritic retinal artery occlusion (A-RAO) associated with giant cell arteritis (GCA). The four primary types of A-RAO were central retinal artery occlusion (CRAO), hemi-central retinal artery occlusion (hCRAO), branch retinal artery occlusion (BRAO), and cilioretinal artery occlusion (CLRAO). The most reported presentation was unilateral CRAO, followed by bilateral CRAO, unilateral CLRAO, and bilateral BRAO. Most RAOs were accompanied by typical GCA signs and symptoms, which can help distinguish them from non-arteritic RAOs. When reported, temporal artery biopsy confirmed GCA in most cases. Patients with GCA may present with a broad spectrum of isolated unilateral and bilateral A-RAOs. [Ophthalmic Surg Lasers Imaging Retina 2024;55:XX-XX.].

Prostanoid signaling in retinal vascular diseases

The vasculature of the retina is exposed to systemic and local factors that have the capacity to induce several retinal vascular diseases, each of which may lead to vision loss. Prostaglandin signaling has arisen as a potential therapeutic target for several of these diseases due to the diverse manners in which these lipid mediators may affect retinal blood vessel function. Previous reports and clinical practices have investigated cyclooxygenase (COX) inhibition by nonsteroidal anti-inflammatory drugs (NSAIDs) to address retinal diseases with varying degrees of success; however, targeting individual prostanoids or their distinct receptors affords more signaling specificity and poses strong potential for therapeutic development. This review offers a comprehensive view of prostanoid signaling involved in five key retinal vascular diseases: retinopathy of prematurity, diabetic retinopathy, age-related macular degeneration, retinal occlusive diseases, and uveitis. Mechanistic and clinical studies of these lipid mediators provide an outlook for therapeutic development with the potential to reduce vision loss in each of these conditions.

Central Retinal Artery Occlusion: Visual Outcomes from a Large Northern California Cohort

PURPOSE

To assess visual acuity (VA) outcomes in a large cohort of patients diagnosed with nonarteritic central retinal artery occlusion (CRAO), and to ascertain whether time from symptom onset to presentation, presenting VA, or conservative treatment delivery (anterior chamber paracentesis, ocular massage, intraocular pressure lowering drugs, hyperventilation, or some combination of those) impacted ultimate VA outcomes.

DESIGN

Retrospective cohort study.

SUBJECTS

The study included 794 patients who presented with CRAO between 2011 and 2020. Within this cohort, 484 individuals presented within 30 days of symptom onset and had comprehensive documentation regarding the details of their presentation, management, and follow-up ≥ 90 days postdiagnosis.

METHODS

Retrospective chart review was conducted for all patients with a diagnosis of CRAO initially identified via International Classification of Diseases coding, followed by confirmation of diagnosis by 2 retina specialists. Cases of arteritic CRAO were excluded.

MAIN OUTCOME MEASURES

Visual acuity recovery, defined as improvement from ≤ 20/200 or worse at presentation to ≥ 20/100 ≥ 90 days after diagnosis.

RESULTS

Of the 794 identified patients, 712 (89.7%) presented with VA of ≤ 20/200. Similarly, 447 (92.4%) of the 484-patient subset that presented within 30 days and had comprehensive documentation presented with VA ≤ 20/200. Of the 441 of those patients with documented follow-up, 380 (86.2%) remained at that level. Of the 244 patients who presented within 4.5 hours of symptom onset, 227 (93%) presented ≤ 20/200 and 201 (92.6%) of the 217 of those with follow-up data did not improve beyond that threshold. There was no significant difference (P < 0.05) in final VA between patients presenting before versus after 4.5 hours from time of vision loss. There was also no significant difference (P < 0.05) in VA outcomes between patients who did or did not receive conservative treatment.

CONCLUSIONS

This large retrospective study further highlights the poor visual prognosis for patients with CRAO. Earlier time to presentation did not seem to impact final VA outcome, nor did conservative treatment efforts. Efficacious evidence-based treatment options are needed for this patient population.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Acute monocular visual loss: time to call the stroke team?

A man in his 90s presented with acute monocular loss of vision; the emergency department triage alerted the stroke team. He underwent urgent parallel assessments by the stroke and ophthalmology teams and was diagnosed with central retinal artery occlusion. The ultimate decision was made to manage him conservatively, rather than with intravenous thrombolysis, and his visual function has remained poor. We discuss the current evidence for using intravenous thrombolysis in people with central retinal artery occlusion and use this case to exemplify the practical issues that must be overcome if ongoing randomised clinical trials of central retinal artery occlusion confirm a definite benefit from using intravenous thrombolysis.

Ink blot leakage in central retinal artery occlusion

PURPOSE

To describe a typical case of acute central retinal artery occlusion (CRAO) with an ink-blot pattern of hyperfluorescent leak on fundus fluorescein angiography (FFA).

CASE DESCRIPTION

A 21-year-old woman came to the clinic with one day of painless right eye vision loss. Her right eye had finger counting at ½ meter. Her right eye had a relative afferent pupillary defect, but her anterior segment and intraocular pressure of both eyes were normal.

RESULTS

The right eye fundus showed signs of acute CRAO with severe grade on optical coherence tomography (OCT). FFA imaging showed a mid-phase hyperfluorescent leak that persisted until the late stage. OCT scan through the hyperfluorescent spot showed absence of neurosensory detachment with normal retinal pigment epithelium, ruling out a central serous chorioretinopathy (CSCR). Ocular massage and anterior chamber paracentesis were performed. At the 10-day follow-up, the patient's visual acuity was counting fingers at ½ meter, and the OCT scan showed findings of CRAO chronicity. The hyperfluorescent spot disappeared on the subsequent FFA.

CONCLUSION

We report a case of ink-blot leakage on FFA, similar to that observed in CSCR in an eye with acute CRAO. We propose that the hyperfluorescent spot in our acute CRAO was likely caused by red blood cell aggregation or rouleaux formation.

Causes and management of sight threatening complications of dermal filler injections: A review

Injectable dermal fillers continue to increase in popularity in aesthetic medicine. Although rare, vision loss secondary to filler injections is a devastating complication associated with a poor visual prognosis. The mechanism for vision loss is thought to be related to retrograde embolization of the dermal filler from peripheral vessels in the face into the ophthalmic arterial system. Early recognition and prompt management are essential if vision is to be salvaged. The use of retrobulbar hyaluronidase is still contentious, however when administered by a specialist, this treatment gives the best chance at visual recovery and should be considered for all cases.

IV Thrombolysis for central retinal artery occlusion - Real-world experience from a comprehensive stroke center

OBJECTIVES

Central retinal artery occlusion (CRAO) is a stroke of the retina potentially amenable to intravenous thrombolysis (IVT). We aimed to determine feasibility of an emergency treatment protocol and risk profile of IVT for CRAO in a comprehensive stroke center (CSC).

METHODS

We performed a retrospective, observational cohort study including patients with acute CRAO admitted to a CSC over 4 years. Patients are offered IVT if they present with acute vision loss of ≤ 20/200 in the affected eye, have no other cause of vision loss (incorporating a dilated ophthalmologic exam), and meet criteria akin to acute ischemic stroke. We collected socio-demographic data, triage data, time from onset to presentation, IVT candidacy, and rates of symptomatic intracranial hemorrhage (sICH)- or extracranial hemorrhage.

RESULTS

36 patients presented within the study period, mean (standard deviation (SD)) age of 70.7 (10), 52 % female, and median time (Q1, Q3) to ED presentation of 13.5 (4.3, 18.8) h. Patients within 4.5 h from onset presented more commonly directly to our ED (66.6 % vs 37.1 %, p = 0.1). Nine patients (25 %) presented within the 4.5 h window. Of those eligible, 7 (77 %) received IVT. There were no events of intracranial or extracranial hemorrhage.

CONCLUSIONS

Our study confirmed that IVT for acute CRAO is feasible. We found a high rate of treatment with IVT of those eligible. However, because 75 % of patients presented outside the treatment window, continued educational efforts are needed to improve rapid triage to emergency departments to facilitate evaluation for possible candidacy with IVT.

Aetiology, Diagnosis and Treatment of Arterial Occlusions of the Retina-A Narrative Review

Arterial occlusions of the retina are potentially sight-threatening diseases which often result in profound visual loss. The aim of this narrative review is to provide an overview of the aetiology, discuss major risk factors, describe the management and systemic assessments and evaluate existing therapies. For this review, an extensive literature search in PubMed was performed. Emboli from the heart or the carotid arteries can cause ophthalmic artery occlusion (OAO), central retinal artery occlusion (CRAO) and branch retinal artery occlusion (BRAO). Most patients with arterial occlusions have vascular risk factors such as arterial hypertension, hyperhomocysteinaemia, carotid stenosis and atrial fibrillation, which also increase the risk of cerebral stroke and myocardial infarction. Therapies such as ocular massage, thrombolysis and anterior chamber paracentesis have been suggested but are still equivocal. However, it is evident that retinal artery occlusion should be immediately treated and accompanied by interdisciplinary collaboration, since early diagnosis and the proper treatment of possible risk factors are important to reduce the risk of further damage, recurrences, other vascular diseases and mortality.

Wilderness Medical Society Clinical Practice Guidelines for Treatment of Eye Injuries and Illnesses in the Wilderness: 2024 Update

A panel convened to develop an evidence-based set of guidelines for the recognition and treatment of eye injuries and illnesses that may occur in the wilderness. These guidelines are meant to serve as a tool to help wilderness providers accurately identify and subsequently treat or evacuate for a variety of ophthalmologic complaints. Recommendations are graded based on the quality of their supporting evidence and the balance between risks and benefits according to criteria developed by the American College of Chest Physicians.

A Review of Current Literature on Central Retinal Artery Occlusion: Its Pathogenesis, Clinical Management, and Treatment

The ocular analogue of a cerebral stroke is central retinal artery occlusion (CRAO), a medical emergency concerning the eyes. Most patients experience substantial acute vision loss with a visual acuity of 20/400 or worse, resulting in decreased quality of life (QoL) and decreased functional ability. An impending cerebral stroke and ischemic heart disease are also more likely. The four distinct clinical entities that make up CRAO are non-arteritic CRAO, transitory non-arteritic CRAO, non-arteritic CRAO with cilioretinal artery sparing, and arteritic CRAO. Depending on the CRAO type, clinical traits, visual results, and treatment all vary greatly. Contrary to current belief, there is a spontaneous improvement in the optical field and vision, mainly in the first week. The likelihood of instinctive development in optical acuity in the first seven days varies greatly. The pathogenesis, epidemiology, and medical features of CRAO will be described in this review, along with present and potential management future options.

Neovascular Glaucoma Complicating Central Retinal Artery Occlusion Despite Cilioretinal Artery Sparing

This case report aims to describe a case of unilateral central retinal artery occlusion (CRAO) with cilioretinal artery sparing, which was complicated by neovascular glaucoma (NVG). A 75-year-old Indian woman with underlying normal tension glaucoma presented with the sudden onset of painless generalized blurring of the right eye's vision for a week. Her right eye vision was hand motion with the presence of a right relative afferent pupillary defect. Fundus examination revealed retinal whitening over the macula sparing the papillomacular bundle with generalized retinal arteriolar attenuation, which was suggestive of right CRAO with cilioretinal artery sparing. Systemic examination revealed high blood pressure (175/75 mmHg) without ocular bruit or audible murmur on auscultation. Optical coherence tomography of the macula showed inner retinal thickening over the temporal macula. Ultrasound carotid Doppler and computed tomography angiography of the carotid showed more than 75% stenosis over the right distal internal carotid artery. Unfortunately, she developed rubeosis iridis over her right eye two weeks after her presentation, which required pan-retinal photocoagulation. She subsequently progressed to NVG, requiring maximum anti-glaucoma medications to stabilize intraocular pressure. In conclusion, CRAO is a sight-threatening medical emergency. Thorough investigations are required to determine the underlying cause so that early intervention can be done to reduce the risk of a similar attack in the fellow eye and the risk of a cerebrovascular event or cardiac ischemia, which could be life-threatening. The presence of a cilioretinal artery does not prevent ocular neovascularization in CRAO. Hence, patients should also be closely monitored after the initial diagnosis to prevent devastating complications such as NVG.

Neuroprotection for Nonarteritic Central Retinal Artery Occlusion: Lessons from Acute Ischemic Stroke

Nonarteritic central retinal artery occlusion (NA-CRAO) is a variant of acute ischemic stroke (AIS) and is a cause of sudden severe loss of vision. There are guidelines by the American Heart Association and the American Stroke Association for the care of CRAO patients. This review explores the basis of retinal neuroprotection for CRAO and its potential for improving the outcome of NA-CRAO. Recently, there have been significant advances in research into the use of neuroprotection to treat retinal diseases, including retinal detachment, age-related macular degeneration, and inherited retinal diseases. Also, neuroprotective research in AIS has been extensive, and newer drugs tested, including Uric acid, Nerinetide, and Otaplimastat, with promising results. Progress in cerebral neuroprotection after AIS offers hope for retinal neuroprotection after CRAO; and a possibility of extrapolating research findings from AIS into CRAO. Combining neuroprotection and thrombolysis can extend the therapeutic window for NA-CRAO treatment and potentially improve outcomes. Experimented neuroprotection for CRAO includes Angiopoietin (Comp Ang1), KUS 121, Gene therapy (XIAP), and hypothermia. Efforts in the field of neuroprotection for NA-CRAO should focus on better imaging to delineate the penumbra after an acute episode of NA-CRAO (using a combination of high-definition optical coherence angiography and electrophysiology). Also, research should explore details of pathophysiologic mechanisms involved in NA-CRAO, allowing for further neuroprotective intervention, and closing the gap between preclinical and clinical neuroprotection.

Dibazol-induced relaxation of ophthalmic artery in C57BL/6J mice is correlated with the potency to inhibit voltage-gated Ca2+ channels

We aimed to explore the effect of dibazol on the ophthalmic artery (OA) and ophthalmic artery smooth muscle cells (OASMCs) of C57BL/6J mice as well as the underlying mechanisms. The OA of C57BL/6J mice was isolated under a dissecting microscope for primary OASMCs culture and myogenic tests. OASMCs were identified through morphological and immunofluorescence analyses. Morphology changes in the OASMCs were examined by staining using rhodamine-phalloidin. We performed a collagen gel contraction assay to measure the contractile and relaxant activities of the OASMCs. The molecular probe Fluo-4 AM was used to examine intracellular free Ca²⁺ levels ([Ca²⁺]_in). The myogenic effects of OA were examined using wire myography. Additionally, the whole-cell patch-clamp technique was used to investigate the mechanisms underlying the relaxant effect of dibazol on L-type voltage-gated Ca²⁺ channels (LVGC) in isolated cells. 10^-5 M dibazol significantly inhibited the contraction of OASMCs and increased the [Ca²⁺]_in response to 30 mM KCl in a concentration-dependent manner. Dizabol had a more significant relaxant effect than 10^-5 M isosorbide dinitrate (ISDN). Similarly, dibazol showed a significant dose-dependent relaxant effect on OA contraction induced by 60 mM KCl or 0.3 μM 9,11-Dideoxy-9α,11α-methanoepoxy prostaglandin F_2α (U46619). The current-voltage (I-V) curve revealed that dibazol decreased Ca²⁺ currents in a concentration-dependent manner. In conclusion, dibazol exerted relaxant effects on the OA and OASMCs, which may involve the inhibition of the Ca²⁺ influx through LVGC in the cells.

Characterization of Oxygen Nanobubbles and In Vitro Evaluation of Retinal Cells in Hypoxia

Purpose

Vein or artery occlusion causes a hypoxic environment by preventing oxygen delivery and diffusion to tissues. Diseases such as retinal vein occlusion, central retinal artery occlusion, or diabetic retinopathy create a stroke-type condition that leads to functional blindness in the effected eye. We aim to develop an oxygen delivery system consisting of oxygen nanobubbles (ONBs) that can mitigate retinal ischemia during a severe hypoxic event such as central retinal artery occlusion.

Methods

ONBs were synthesized to encapsulate oxygen saturated molecular medical grade water. Stability, oxygen release, biocompatibility, reactive oxygen species, superoxide, MTT, and terminal uridine nick-end labeling assays were performed. Cell viability was evaluated, and safety experiments were conducted in rabbits.

Results

The ONBs were approximately 220 nm in diameter, with a zeta potential of -58.8 mV. Oxygen release studies indicated that 74.06 µg of O2 is released from the ONBs after 12 hours at 37°C. Cell studies indicated that ONBs are safe and cells are viable. There was no significant increase in reactive oxygen species, superoxide, or double-stranded DNA damage after ONB treatment. ONBs preserve mitochondrial function and viability. Histological sections from rabbit eyes indicated that ONBs were not toxic.

Conclusions

The ONBs proposed have excellent oxygen holding and release properties to mitigate ischemic conditions in the retina. They are sterile, stable, and nontoxic.

Translation Relevance

ONB technology was evaluated for its physical properties, oxygen release, sterility, stability, and safety. Our results indicate that ONBs could be a viable treatment approach to mitigate hypoxia during ischemic conditions in the eye upon timely administration.

Exploratory clinical trial to evaluate the efficacy and safety of transdermal electrical stimulation in patients with central retinal artery occlusion

PURPOSE

To evaluate the efficacy and safety of transdermal electrical stimulation (TdES) using skin electrodes in patients with central retinal artery occlusion (CRAO).

METHODS

Five eyes of five patients with CRAO underwent TdES (10-ms biphasic pulses, 20 Hz, 30 min) six times at 2-week intervals. Only the affected eye was stimulated with 1.0-mA pulses in all patients. The primary endpoint was the best-corrected logMAR visual acuity. The secondary endpoints were changes in the best-corrected logMAR visual acuity, Early Treatment of Diabetic Retinopathy Study (ETDRS) visual acuity, mean deviation of the Humphrey field analyzer (HFA) 10-2, and HFA Esterman test score. We also evaluated its safety.

RESULTS

The logMAR visual acuity at 12 weeks was improved by 0.1 or more in two patients and was maintained in two patients compared to the baseline. No obvious changes in the mean logMAR visual acuity, ETDRS visual acuity, mean deviation, and HFA Esterman score were observed at 12 weeks compared to the baseline. All five enrolled patients completed the study according to the protocol. No treatment-related adverse events were observed during this study.

CONCLUSION

In this study, logMAR visual acuity was slightly improved in two patients, confirming the safety of TdES. Since CRAO has no established treatment method, further research into the effects of TdES treatment in CRAO patients may be beneficial.

The effect of COVID-19 pandemic and wearing face masks on ophthalmology practice: What is known so far? A narrative review

Face masks, along with other preventive measures, can help slow the spread of COVID-19. Despite the positive effect of the mask in combating the virus, it has some negative effects on the human body that must be followed up on and reduced. In this study, we discuss the impact of wearing face masks on the eye and the common issues associated with using them. The literature search was conducted using electronic databases such as PubMed and Google Scholar. Only articles published in English were included. A total of 39 relevant articles were deemed eligible. After the duplicate articles were removed, the titles and abstracts of 20 papers underwent full-text screening. The review comprised both prospective and retrospective investigations, case reports, and a series of reporting ocular symptoms following the use of face masks. The COVID-19 pandemic affected ophthalmology practices in managing patients. New factors must be considered, especially when dealing with anti-VEGF injections, such as the risk of endophthalmitis, tests and symptoms of patients with glaucoma, and the emerging symptoms associated with the COVID-19 vaccination. The use of face masks and breathing aids seemed to influence the tear film.

Perioperative Care of the Patient with Eye Pathologies Undergoing Nonocular Surgery

The authors reviewed perioperative ocular complications and implications of ocular diseases during nonocular surgeries. Exposure keratopathy, the most common perioperative eye injury, is preventable. Ischemic optic neuropathy, the leading cause of perioperative blindness, has well-defined risk factors. The incidence of ischemic optic neuropathy after spine fusion, but not cardiac surgery, has been decreasing. Central retinal artery occlusion during spine fusion surgery can be prevented by protecting eyes from compression. Perioperative acute angle closure glaucoma is a vision-threatening emergency that can be successfully treated by rapid reduction of elevated intraocular pressure. Differential diagnoses of visual dysfunction in the perioperative period and treatments are detailed. Although glaucoma is increasingly prevalent and often questions arise concerning perioperative anesthetic management, evidence-based recommendations to guide safe anesthesia care in patients with glaucoma are currently lacking. Patients with low vision present challenges to the anesthesia provider that are becoming more common as the population ages.

Risk Factors and Treatment Strategy for Retinal Vascular Occlusive Diseases

Retinal occlusive diseases are common diseases that can lead to visual impairment. Retinal artery occlusion and retinal vein occlusion are included in the clinical entity, but they have quite different pathophysiologies. Retinal artery occlusion is an emergent eye disorder. Retinal artery occlusion is mainly caused by thromboembolism, which frequently occurs in conjunction with life-threatening stroke and cardiovascular diseases. Therefore, prompt examinations and interventions for systemic vascular diseases are often necessary for these patients. Retinal vein occlusion is characterized by retinal hemorrhage and ischemia, which may impair visual function via several complications such as macular edema, macular ischemia, vitreous hemorrhage, and neovascular glaucoma. Even though anti-vascular endothelial growth factor therapy is the current established first-line of treatment for retinal vein occlusion, several clinical studies have been performed to identify better treatment protocols and new therapeutic options. In this review, we summarize the current findings and advances in knowledge regarding retinal occlusive diseases, particularly focusing on recent studies, in order to provide an update for a better understanding of its pathogenesis.

Central Retinal Artery: A Human Fetal Cadaveric Study with Histological Correlation

The optic nerve is the second cranial nerve. It is supplied by the central retinal artery. It is said that this artery starts getting incorporated within the optic nerve at around the sixth week of gestation, and by the ninth week it is entirely inside the optic nerve. However, the point of incorporation lies in the intraorbital course of the optic nerve. The present study aimed at identifying the location of the central retinal artery inside the optic nerve, i.e. the peripheral or central position. Human fetuses of second and third trimester were dissected to expose the optic nerve. Morphometric measurements were taken and sectioned in 3 regions. These transverse sections were subjected to histological procedures. The results showed that the central retinal artery, at its entry into the optic nerve, was peripheral and inferior in 3 of 25 optic nerves and peripheral and lateral in the remaining optic nerves. However, the arteries were all centrally placed, close to the posterior pole of the eyeball. These findings are important for the ophthalmologist in identifying certain congenital anomalies of the eyeball in neonates.

Assessment of the impact of N95 respirators or surgical masks use on the retinal microvasculature

PURPOSE

To determine the possible impact of wearing N95 respirator or surgical masks on retinal vessel diameters and choroidal thickness in healthy healthcare workers.

METHODS

Diameters of peripapillary retinal arteries and veins and choroidal thickness values at the foveal center and at 1000 μm distances from the foveal center in both nasal and temporal directions were measured before mask wearing using a spectral-domain optical coherence tomography. After four hours (h) of N95 or surgical mask wearing vessel diameter and choroidal thickness measurements were repeated.

RESULTS

A total of 52 eyes from 52 participants (28 F [53.8%]; 24 M [46.2%]) were enrolled in this study. The mean age of patients was 34.58 ± 5.24 years (25-44 years). The diameters of all measured arteries [inferior temporal artery (p = 0.003), superior temporal artery (p < 0.001), inferior nasal artery (p = 0.003), and superior nasal artery (p = 0.004)] and veins,with the exception of superior nasal vein, (inferior temporal vein (p = 0.031), superior temporal vein (p = 0.027), inferior nasal vein (p < 0.001), and superior nasal vein (p = 0.063)] increased significantly after four hour use of N95 respirators and surgical maskswhen compared to baseline. There was also a significant diameter increase of the superior temporal (p < 0.001), inferior nasal veins (p < 0.001), and superior temporal artery (p = 0.037) for N95 respirators and surgical masks use, respectively. The differences in central subfoveal, temporal, and nasal choroidal thickness between baseline and after 4 h use of N95 respirators were statistically significant (From 366.73 ± 70.81 μm to 381.23 ± 69.29μm,p < 0.001 for the subfoveal; from 324.00 ± 64.13μm to 335.40 ± 61.35 μm, p = 0.007 for the temporal; from 297.40 ± 68.18 μm to 308.23 ± 74.51μm, p = 0.002 for the nasal thicknesses). Choroidal thickness values were also increased with surgical mask use. But only the increase in central subfoveal thickness was statistically significant (From 366.78 ± 71.00 μm to 372.58 ± 76.56 μm, p = 0.031 for the central subfoveal; from 297.42 ± 68.35 μmto 302.79 ± 73.05 μm, p = 0.068 for the nasal; from 324.01 ± 64.21μm to 330.33 ± 65.84, p = 0.117 for the temporal thicknesses).

CONCLUSION

With four hours use of N95 respirators or surgical face masks, retinal vessel diameters and choroidal thicknesses showed an increase in comparison to baseline measurements. Hemodynamic changes seen secondary to hypercapnia due to prolonged use of N95 respirators or surgical masks may also be observed in the retinal and choroidal circulation. Furthermore, the use of face masks should be taken into account while assessing the retinal microvasculature.

The effects of carbogen and hyperbaric oxygen treatment on fracture healing in rats

BACKGROUND

Bone fractures and fracture healing are one of the most common problems among orthopedic surgeons. In this study, we investigated the effects of hyperbaric oxygen (HBO) and carbogen (C) treatment on fracture healing in the experimental animal model.

METHODS

Twenty-four male Wistar-Albino rats were randomly divided into three groups as Group 1 (C inhalation therapy), Group 2 (HBO inhalation therapy), and Group 3 (control group), with eight rats in each group. HBO and C treatment were given to the rats in Group 1 and Group 2 1 week before the surgical procedure and 3 weeks after the surgical procedure. Following the surgical procedure, all rats were killed at the end of the 3rd week and the healing tissue in the fracture line was evaluated clinically, radiologically, and histopathologically.

RESULTS

Although there were higher histopathological, radiological, and clinical scores in the HBO and C groups in terms of frac-ture healing compared to the control group, there was no statistically significant difference between the groups.

CONCLUSION

There are many studies in the literature that examine the systemic and local effects of HBO and C treatments and show that they increase tissue oxygenation. Our study showed that HBO and C groups had no beneficial or harmful effects on fracture healing compared to the control group.

Central Retinal Artery Occlusion after Rhinoplasty Surgery: A Case Report and Literature Review

Aim. This study was aimed at reporting a case of central retinal artery occlusion (CRAO) after rhinoplasty. Case Report. Unilateral blindness occurred in a 22-year-old woman after rhinoplasty with a history of transient visual loss due to migraine aura and vasospasm. The physical examination of the patient revealed a visual acuity of no light perception in the right eye, a 4+ relative afferent pupillary defect, disc swelling, cherry-red spot in the macula, and ischemic retina in the right eye. Based on the diagnosis of CRAO, the patient underwent anterior chamber paracentesis (AC tap) along with treatment with mannitol and intravenous hydrocortisone. Visual acuity improved to 1/10 after a two-month follow-up. Conclusion. Taking history is very important in rhinoplasty surgery, and vasoconstrictors should be limited in the patients with a suspected history of vasospasm.

Ocular ischaemia: signs, symptoms, and clinical considerations for primary eye care practitioners

Ischaemic stroke is a major disease burden as well as a leading cause of death. Early signs of ischaemic stroke can manifest in the eye, placing primary eyecare practitioners in an important position to identify patients at risk of ischaemic stroke and initiate suitable referral pathways. The vascular supply to the brain is reviewed with reference to vision including the various retinal signs and ocular symptoms associated with transient ischaemic attacks and ischaemic stroke. Using a range of clinical cases, the diverse clinical presentations of retinal embolic events, as well as other forms of vascular occlusion, are highlighted and the underlying pathophysiology is discussed. A succinct scheme for the assessment and management of ischaemic events for primary eye care practitioners is provided.

A review of the management of central retinal artery occlusion

Central retinal artery occlusion (CRAO), the ocular analog of a cerebral stroke, is an ophthalmic emergency. The visual prognosis for overall spontaneous visual recovery in CRAO is low. Furthermore, the risk of future ischemic heart disease and cerebral stroke is increased due to the underlying atherosclerotic risk factors. There is currently no guideline-endorsed treatment for CRAO. This review will describe the anatomy, pathophysiology, epidemiology, and clinical features of CRAO, and investigate the current and future management strategies.

Vision Loss Secondary to Facial and Periorbital Steroid Injection: A Systematic Review

PURPOSE

The risk of ophthalmic and retinal artery occlusions following facial and periorbital steroid injection has not been explored. This systematic review examines the prevalence, risk factors, and treatment outcomes of steroid-induced vision losses.

METHODS

A literature search in Evidence Based Medicine Reviews, MEDLINE, Embase, Pubmed, ClinicalTrials, and WHO ICTRP was performed for vision loss following facial and periorbital corticosteroid injections through July 2020.

RESULTS

Of 35 case reports, series, and reviews, 49 patients (56 eyes) with steroid-induced vision loss were analyzed. Injection sites predominantly involved the nose (45%) and periocular regions (10%). The most common type of steroid is triamcinolone (54%). Most cases were unilateral, except 7 cases of bilateral vision losses, 4 of which resulted from unilateral steroid injection. Symptoms were reported during or immediately after injections in 49% of cases. Most occlusions occurred in the ophthalmic (53%) or central retinal artery (33%). Vision most commonly presented as no light perception (37%), and 90% were 20/200 or worse. Final visual outcomes varied from 20/200 or worse (56%), 20/40 or better (30%), to in between (13%).

CONCLUSION

Most vision losses resulted from steroid injections in the nasal and periorbital area. Triamcinolone was the most common offending agent, likely due to large particle size, low solubility, and extensive particle aggregation. Dexamethasone has the opposite pharmacologic properties and has never been reported in association with vascular occlusion related vision loss. Careful steroid selection, injection techniques, and treatment strategies should be considered to prevent and treat artery occlusion.

CASE SERIES OF HYPERBARIC OXYGEN THERAPY FOR CENTRAL RETINAL ARTERY OCCLUSION

PURPOSE

To retrospectively report the outcomes of patients presenting to our facility with central retinal artery occlusion and receiving therapy with hyperbaric oxygen (HBO).

METHODS

This was a retrospective, chart review at a single hospital center. Patients with diagnosed central retinal artery occlusion were treated with HBO twice daily for 5 days during their inpatient stay for a total of 10 HBO treatments. Main outcome was change from the documented presenting best-corrected visual acuity to discharge best-corrected visual acuity. Thirty-nine patients with central retinal artery occlusion were included in the analysis during a 30-month period.

RESULTS

Twenty-eight of 39 patients (72%) had some improvement in acuity. There was a mean of 5.05 lines of improvement using a modified Snellen chart after completing their HBO treatment course. Patients treated within 12 hours of symptom onset showed the greatest improvement in their visual acuity (6.11 mean lines of improvement). Complications of therapy included middle ear barotrauma (10/39) and confinement anxiety (1/39) and did not interfere with the therapy regimen or hospital course.

CONCLUSION

This retrospective case series supports the use of emergent HBO therapy as a viable treatment option for patients with central retinal artery occlusion. Hyperbaric oxygen therapy was safely administered and well tolerated.

Thrombolysis for Central Retinal Artery Occlusion in 2020: Time Is Vision!

BACKGROUND

Acute nonarteritic central retinal artery occlusion (CRAO) is an eye stroke with poor visual prognosis and no proven effective therapies. Given advances in acute stroke care, thrombolysis in CRAO merits critical re-examination. We review the evidence for intravenous (IV) and intra-arterial (IA) tissue plasminogen activator (tPA) in CRAO management.

EVIDENCE ACQUISITION

MEDLINE, Scopus, and Cochrane online databases were systematically searched from 1960 to present, for reports of acute IV or IA therapy with alteplase or tenecteplase in nonarteritic CRAO patients. English language case reports, case series, interventional studies, or randomized controlled trials were included. The study type, age and number of subjects, the regimen administered, the time since symptoms' onset, visual outcome, and safety reports were noted.

RESULTS

Use of IV thrombolysis with alteplase was reported in 7 articles encompassing 111 patients, with 54% of them receiving IV tPA within 4.5 hours of symptom onset, and none developing symptomatic intracranial or ocular hemorrhage. Six studies described IA alteplase administration, with only 18 of a total of 134 patients (13.4%) treated within the first 6 hours after visual loss. The reported adverse events were minimal. Visual outcomes post-IV and IA thrombolysis were heterogeneously reported; however, most studies demonstrated benefit of the respective reperfusion therapies when administered very early. We found no reports of tenecteplase administration in CRAO.

CONCLUSIONS

In 2020, nonarteritic CRAO patients should theoretically receive the same thrombolytic therapies, in the same time window, as patients with acute cerebral ischemia. Eye stroke and teleeye stroke code encounters must include an expert ophthalmologic evaluation to confirm the correct diagnosis and to evaluate for ocular signs that may help guide IV tPA administration or IA management. Future research should focus on developing feasible retinal penumbra imaging studies that, similar to cerebral tissue viability or perfusion imaging, can be incorporated into the thrombolysis decision-making algorithm.

Detection of Central Retinal Artery Occlusion by Point-of-Care Ultrasound in the Emergency Department: A Case Series

Central retinal artery occlusion (CRAO) is a rare, but serious, diagnosis that can lead to blindness, most often due to thromboembolic disease. In the emergency department (ED), CRAO can present as acute, painless loss of vision. Physicians need quick ways to rule in this diagnosis due to the time-sensitive nature of the event. We describe two patients in this cases series who present to the same ED with unilateral painless vision loss and histories that include notable risk factors such as thromboembolic and atherosclerotic disease. Upon arrival, point-of-care ultrasound (POCUS) done at the bedside allowed for quick determination of CRAO. ​​​​​​​The importance of this case series is to emphasize the efficacy of POCUS in evaluating patients with painless vision loss in the ED setting. 

Clinical Manifestations and Visual Prognosis of Cilioretinal Artery Sparing Central Retinal Artery Occlusion

Purpose

To investigate the clinical manifestations and prognosis of eyes with cilioretinal artery sparing central retinal artery occlusion (CRAO).

Methods

A retrospective study was conducted on 90 eyes diagnosed with complete CRAO, including 16 cases of cilioretinal artery sparing CRAO. Clinical features, visual outcome, papillomacular bundle involvement, and remnant visual field were analyzed according to cilioretinal artery sparing.

Results

Among eyes with complete CRAO, the proportion of cilioretinal artery sparing CRAO was 17.8% (16 / 90). Mean initial best-corrected visual acuities (BCVAs) (2.04 ± 0.69 vs. 2.34 ± 0.47, p = 0.039) and final BCVAs (1.65 ± 0.87 vs. 2.22 ± 0.84, p = 0.001) were significantly better in eyes of the cilioretinal artery sparing group than the non-sparing group. The proportion with poor visual outcome (final BCVA <20 / 200) was 81.3% in the cilioretinal artery sparing group and 97.3% in the non-sparing group (p = 0.01). In sub-group analysis within cilioretinal artery sparing CRAO eyes, ischemic involvement of the papillomacular bundle at disease onset was significantly more frequent in the poor vision group (BCVA <20 / 200, 12 / 13 [92.3%]) than in the good vision group (BCVA ≥20 / 200, 1 / 3 [33.3%], p = 0.016) and it was associated with preserved central visual field.

Conclusions

Although cilioretinal artery sparing is common in CRAO and has a better prognosis than complete CRAO, the visual outcome is generally poor and only a small proportion of eyes has preserved small central visual field. Ischemic injury of the papillomacular bundle at the acute stage of CRAO correlates with poor visual outcome and could be a prognostic sign.

The actual role of thrombolytic treatment in central retinal artery occlusion

OBJECTIVE

The purpose of this study is to determine the application of thrombolytic treatment in central retinal artery occlusion (CRAO), its real benefit, safety and possible indications for treatment.

METHODS

We searched the PubMed, Cochrane and Google Scholar databases delving first into the effectiveness of the traditional treatment for CRAO, and then comparing them with new treatment strategies with intra venous or intra arterial fibrinolysis.

RESULTS

Whereas small retrospective and open-label observational trials support the use of thrombolytic therapy, multicenter randomized trials failed to demonstrate a significant visual improvement with this new strategy. Besides that, a greater risk of life threatening adverse event was observed in patients using thrombolytic treatment.

CONCLUSION

Until well-conducted clinical trials demonstrate a clear benefit of thrombolytic therapy for improving visual acuity and their benefit are weighted against the frequency and severity of adverse events, we could not recommend fibrinolysis for treating CRAO.

Central retinal artery occlusion after catheter ablation of atrial fibrillation

Central retinal artery occlusion (CRAO) is a rare but severe and urgent complication of atrial fibrillation ablation. Awareness of this ophthalmologic complication and prompt treatment are needed because ischemic damage to the retina is irreversible from 4 hours after the onset of CRAO.

The use of multimodal imaging in the evaluation of a patient with central retinal artery occlusion in the setting of asteroid hyalosis: a case report

Background

A central retinal artery occlusion (CRAO) is an ophthalmic emergency due to its strong association with cerebrovascular and cardiovascular morbidity and mortality. A timely diagnosis is necessary but difficult in the setting of dense asteroid hyalosis, as typical fundoscopic findings can be obscured. We present a case where multimodal imaging in an eye with an obscured fundus could lead to timely diagnosis and management of CRAO in a patient with acute vision loss.

Case presentation

A 94-year-old Caucasian woman with a history of exudative macular degeneration presented to the retina clinic with acute vision loss in one eye over the course of an afternoon. The patient had dense asteroid hyalosis, and a direct retinal exam was not possible. Multimodal imaging suggested a CRAO diagnosis. The patient received digital ocular massage directly prior to undergoing fluorescein angiography (FANG), which confirmed the diagnosis. The patient was transported from clinic to the emergency room for an emergency stroke workup, which revealed a spontaneous echo in the left atrial appendage, and the patient was started on antiplatelet therapy. When she presented for follow-up within a week, the patient noted that her vision had improved at the time of digital ocular massage and continued to improve thereafter. Her FANG showed marked reperfusion of the retina, and she subsequently has completely regained her baseline visual acuity.

Conclusions

Multimodal imaging is useful in evaluating visual loss in patients with acute vision loss. In addition, ocular massage is a simple, low-risk intervention that may have benefit in the treatment of acute CRAO. Patients who present to ophthalmologists with an acute CRAO need an emergency referral for evaluation of cerebrovascular and cardiovascular comorbidities.

Evaluation of the effect of n95 face mask used by healthcare professionals on choroidal thickness

PURPOSE

We aimed to show the changes in choroidal thickness (CT) with spectral domain optical coherence tomography (SD-OCT) after prolonged use of N95 mask.

METHOD

The healthcare workers who use the N95 face-mask, between 30-50 years of age who have best corrected visual acuity (BCVA) ≥10/10, spherical or cylindrical refraction errors less than 2 diopters, with normal intra ocular pressure (IOP), axial length (AL) between 22-24 mm included in the study. The choroid was imaged with enhanced depth imaging (EDI) techniques using SD-OCT. CT was measured, subfoveal, at 1000 μm nasal and temporal of the center of the fovea. Measurements were first made after wearing the N95 mask for at least 2 h without removing it and repeated 15 min after removing.

RESULTS

After 2 h of the N95 mask using without removal, the mean subfoveal CT was 293.56 ± 76.12(min:185, max:479), the mean temporal CT was 253.81 ± 63.48(min:172, max:384), the mean nasal CT was 239.18 ± 53.92(min:139, max:356). Fifteen minutes after removal of the N95 mask, the mean subfoveal CT was 250.56 ± 52.48(min:172, max:397), the mean temporal was 218.40 ± 53.58(min:129, max:354), the mean nasal CT was 210.67 ± 53.31(min:132, max:366). The differences in subfoveal, temporal and nasal CT between 2 h of N95 mask use and 15 min after removal of the mask were statistically significant (p < 0.05 for each).

CONCLUSION

Hypercapnia due to prolonged use of the N95 mask may cause choroidal hemodynamic changes and transient increased choroidal thickness.

Neuro-Ophthalmic Emergencies

Neuro-ophthalmic emergencies include optic nerve, central visual pathway, and ocular motility disorders that, if not identified and treated promptly, may lead to permanent vision loss, other significant morbidity, or mortality. This article provides a framework for approaching patients with neuro-ophthalmic symptoms and reviews the presentation, evaluation, and treatment of select emergent conditions that can cause them. Emergent causes of blurry vision, transient vision loss, papilledema, and diplopia, including giant cell arteritis, cardioembolic disease, and aggressive infection, are discussed.

Examining the Role of Retrobulbar Hyaluronidase in Reversing Filler-Induced Blindness: A Systematic Review

PURPOSE

To provide a systematic review of the literature concerning retrobulbar hyaluronidase injections as a treatment for hyaluronic acid gel filler-induced blindness and evaluate the level of evidence for this proposed therapy.

METHODS

The authors performed a search of English language articles published on the use of retrobulbar hyaluronidase to reverse vision loss precipitated by hyaluronic acid gel fillers. Articles reviewed included case reports/series, experimental investigations, expert opinion commentaries, and major reviews. To date, there have been no case-control, cohort, or randomized control studies to evaluate this treatment. Five anecdotal descriptions of hyaluronic acid gel filler blindness treated specifically with retrobulbar hyaluronidase were identified, for a total of 9 patients. One hundred twelve articles in total on this treatment and related topics, including filler-induced blindness and alternative treatments, were identified and reviewed.

RESULTS

Of the 9 documented cases of patients treated with retrobulbar hyaluronidase for hyaluronic acid-induced blindness, visual improvement was demonstrated in 2 cases. The successes, however, are undermined by inconsistent pretreatment ophthalmic assessment and documentation. Animal studies demonstrate mixed results. Laboratory studies document the inability of hyaluronidase to cross the optic nerve sheath.

CONCLUSIONS

There is not currently enough evidence to support retrobulbar hyaluronidase as a treatment for filler-induced blindness. Additional studies are needed to further evaluate its efficacy and explore alternative treatments.

Retinal hypoxia and angiogenesis with methamphetamine

Central retinal artery occlusion, retinopathy, and retinal neovascularization have been reported in methamphetamine (METH) abusers. In the current study, we investigated whether METH induces retinal neovascularization in a mouse model, and if so, whether the neovascularization is associated with increased hypoxia, hypoxia-inducible factor 1α (HIF-1α), and vascular endothelial growth factor (VEGF). Mice were administrated METH by intraperitoneal injection over a 26-day period, or injected with saline as a vehicle control. The number of retinal arterioles and venules were counted using in vivo live imaging following infusion with fluorescein isothiocyanate-dextran. Excised retinas were stained with griffonia simplicifolia lectin I and flat mounted for a measurement of vascularity (length of vessels per tissue area) with AngioTool. Retinal hypoxia was examined by formation of pimonidazole adducts with an anti-pimonidazole antibody, and HIF-1α and VEGFa protein levels in the retina were detected by immunoblot. METH administration increased vascularity (including the number of arterioles) measured on Day 26. Retinal VEGFa protein level was not changed in METH-treated mice on Day 5, but was increased on Day 12 and Day 26. Hypoxia (pimonidazole adduct formation) was increased in retinas of METH-treated mice on Day 12 and Day 26, as were HIF-1α protein expression levels. These results indicate that METH administration induces hypoxia, HIF-1α, VEGFa, and angiogenesis in the retina.

Conservative treatments for acute nonarteritic central retinal artery occlusion: Do they work?

Acute central retinal arterial occlusion has a very poor visual prognosis. Unfortunately, there is a dearth of evidence to support the use of any of the so-called "conservative" treatment options for CRAO, and the use of thrombolytics remains controversial. In this review, we address a variety of these "conservative" pharmacologic treatments (pentoxifylline, isosorbide dinitrate, and acetazolamide) and nonpharmacologic approaches (carbogen, hyperbaric oxygen, ocular massage, anterior chamber paracentesis, laser embolectomy, and hemodilution) that have been proposed as potential treatments of this condition. We conclude that the available evidence for all treatments is insufficient to conclude that any treatment will influence the natural history of this disorder. Management of CRAO patients should instead focus on reducing the risk of subsequent ischemic events, including cerebral stroke. Certain patients may be considered for acute treatment with thrombolytics, although further research must clarify the efficacy, safety, and optimal use of these therapies.

Management of Acute Central Retinal Artery Occlusion, a "Retinal Stroke": An Institutional Series and Literature Review

OBJECTIVES

Acute central retinal artery occlusion (CRAO) is an ophthalmologic emergency that often results in permanent vision loss. Over 25% are associated with acute cerebral ischemia. In the absence of existing Level I treatment options, this study aims to examine institutional practice patterns and review the literature to develop a formalized approach to the treatment of CRAO in the era of ischemic stroke protocols.

MATERIALS AND METHODS

This is a retrospective review of institutional practices in the workup and treatment of patients diagnosed with acute non-arteritic (NA) CRAO at a single center from January 2017 to August 2020.

RESULTS

Of 91 patients managed for acute NA-CRAO, 62.6% were male and average age was 66.4 years. Only 20.9% of patients presented within 4 h of symptom onset. 12.1% of patients had evidence of acute stroke on MRI, and 27.5% had ipsilateral internal carotid artery stenosis >50%. Half (52.7%) did not receive any acute treatment for CRAO, excluding antiplatelet/anticoagulation. 48.5% of patients undergoing acute medical treatment had improved visual acuity compared to 29.4% without treatment (p=0.14).

CONCLUSIONS

There is a lack of clear protocol for the management of NA-CRAO. While not reaching statistical significance, our experience mirrors the literature with patients undergoing medical treatment demonstrating improved visual acuity over those without treatment. Given the presence of acute ischemic stroke, carotid disease, and/or stroke risk factors in over 25% of patients with CRAO, multidisciplinary involvement and modern stroke algorithms should be considered for this disease.

Evaluating Retinal and Choroidal Perfusion Changes After Ocular Massage of Healthy Eyes Using Optical Coherence Tomography Angiography

Background and objectives: Ocular massage (OM) is used as a treatment option for acute retinal artery occlusion, under the assumption that it induces vessel dilatation and enhances perfusion. Since evidence of ocular perfusion alteration due to OM is lacking, we investigate the impact of OM on the hemodynamics of the posterior pole in healthy eyes in a noninvasive fashion by using optical coherence tomography angiography (OCTA). Materials and Methods: A prospective study was conducted on healthy volunteers, each of whom underwent measurements of intraocular pressure (IOP), central macular thickness (CMT), subfoveal choroidal thickness (SFCT), radial peripapillary capillary perfusion (RPCP), superficial capillary plexus perfusion (SCPP), deep capillary plexus perfusion (DCPP), choriocapillaris perfusion (CCP), Sattler’s layer perfusion (SLP) and Haller’s layer perfusion (HLP) before and after OM. OM was performed for 2 min, consisting of 10-s turns of compression and decompression of the globe. Results: A total of 21 eyes from 21 participants (median age 29) were included. After OM, IOP significantly declined (p < 0.001), while SFCT (p < 0.005), SCPP (p < 0.001), DCPP (p = 0.004) and CCP (p = 0.008) significantly increased. CMT, RPCP, SLP and HLP did not show any significant alteration due to OM. Changes in SCPP correlated positively with changes in CCP and vice versa. Conclusions: OCTA-based analysis in healthy adults following OM demonstrated a significant increase of retinal perfusion values, assumed to be due to failure of autoregulatory mechanisms. These findings may indicate a positive effect of OM as a treatment option for patients with acute retinal artery occlusion.

Oxidative Stress and Vascular Dysfunction in the Retina: Therapeutic Strategies

Many retinal diseases, such as diabetic retinopathy, glaucoma, and age-related macular (AMD) degeneration, are associated with elevated reactive oxygen species (ROS) levels. ROS are important intracellular signaling molecules that regulate numerous physiological actions, including vascular reactivity and neuron function. However, excessive ROS formation has been linked to vascular endothelial dysfunction, neuron degeneration, and inflammation in the retina. ROS can directly modify cellular molecules and impair their function. Moreover, ROS can stimulate the production of inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) causing inflammation and cell death. However, there are various compounds with direct or indirect antioxidant activity that have been used to reduce ROS accumulation in animal models and humans. In this review, we report on the physiological and pathophysiological role of ROS in the retina with a special focus on the vascular system. Moreover, we present therapeutic approaches for individual retinal diseases targeting retinal signaling pathways involving ROS.

Arterial Occlusions to the Eye: From Retinal Emboli to Ocular Ischemic Syndrome

: Abstract: A loss or lack of blood supply to the eye can result in acute loss of vision. The site of ischemia may be at the level of the retinal arterioles, the central retinal artery, or further back at the ophthalmic and internal carotid artery. Recognizing the symptoms and signs are important to help prevent permanent ischemic and irreversible blindness. The objective of this review article is to provide the general ophthalmologists with information on how to recognize the symptoms and to best manage these patients. The management is to investigate for the cause of the transient monocular visual loss and to apply secondary prevention to address atherosclerotic risk factors to prevent further ischemic events like a stroke.

Central Retinal Artery Occlusion After Nasosinal Surgery - an Insight

Objective

To describe a case of central retinal artery occlusion (CRAO) after nasosinal surgery and subject's subsequent response to hyperbaric oxygen therapy (HBOT).

Design

Observational case report.

Results

We describe a subject with diagnosed CRAO after septoplasty, bilateral inferior turbinate reduction and balloon sinuplasty, who was given hyperbaric oxygen treatment after four days of onset of CRAO with an improvement in visual acuity and visual field.

Conclusion

Even though CRAO has been rarely reported after ENT procedures and HBOT has been previously described for the treatment, this is the case report where hyperbaric oxygen was given after four days of onset, with a possible improvement.

The M.A.STE.R.S algorithm for acute visual loss management after facial filler injection

OBJECTIVE

To propose an algorithm of treatment for sudden visual loss following filler injections and perform an English-written literature search for assignment of evidence level and grade recommendation.

METHODS

Algorithm of treatment includes ocular physical Maneuvers, hyAluronidase administration, intravenous STEroids, intraocular pressure Reduction, and Supplemental Oxygen (M.A.STE .R.S) based on previous acute management reports. Special consideration for algorithm buildup was made for ophthalmic diseases that share physiopathological features such as central retinal artery occlusion, systemic vasculitis affecting vision, and acute glaucoma. Finally, a systematic cross-review of the reported cases with visual loss was done to identify the level of evidence and grant a recommendation grade.

RESULTS

A search through PubMed and Medscape databases for English-written scientific papers using the terms facial filler, retinal artery occlusion, management, treatment, complications, and adverse events quoted a total of 46 papers (190 cases) which were then analyzed. A high variability on management for treatment of sudden visual loss after facial filler injections was observed. This was attributed partially to the great diversity of medical specialists performing cosmetic facial procedures such as dermatologists, plastic surgeons, esthetic doctors and ophthalmologists, and the lack of high evidence level studies.

CONCLUSIONS

The proposed algorithm provides an initial guideline based on prior literature reports and physiopathology involving facial filler injection complications. Analysis identified 22 successfully treated cases with vision recovery (11.57%). Ocular physical maneuvers had the best evidence-based level and grade recommendation (A) for the management of acute vision loss secondary to facial filler injections.

Iatrogenic ophthalmic artery occlusion and retinal artery occlusion

Iatrogenic ophthalmic artery occlusion (IOAO) is a rare but devastating ophthalmic disease that may cause sudden and permanent visual loss. Understanding the possible etiologic modalities and pathogenic mechanisms of IOAO may prevent its occurrence. There are numerous medical etiologies of IOAO, including cosmetic facial filler injection, intravascular procedures, intravitreal gas or drug injection, retrobulbar anesthesia, intraarterial chemotherapy in retinoblastoma. Non-ocular surgeries and vascular events in arteries that are not directly associated with the ophthalmic artery, can also cause IOAO. Since IOAO has a limited number of treatment modalities, which lead to poor final visual prognosis, it is imperative to acknowledge the information regarding medical procedures that are etiologically associated with IOAO. We accumulated all searchable and available IOAO case reports (our cases and previous reported cases from the literature), classified them according to their mechanisms of pathogenesis, and summarized treatment options and responses of each of the causes. Various sporadic cases of IOAO can be categorized into three mechanisms as follows: intravascular event, orbital compartment syndrome, and increased intraocular pressure. Embolic IOAO, which is considered the primary cause of the condition, was classified into three subgroups according to the pathway of embolic movement (retrograde pathway, anterograde pathway, pathway through collateral channels). Despite the practical limitations of treating spontaneous (non-iatrogenic) retinal artery occlusion, this article will contribute in predicting and improving the prognosis of IOAO by recognizing the treatable factors. Furthermore, it is expected to provide clues to future research associated with the treatment of retinal artery occlusion.