Mimickers of anterior uveitis, scleritis and misdiagnoses- tips and tricks for the cornea specialist

BACKGROUND

Anterior uveitis, inflammation of the anterior chamber and related structures, is a cohort of diseases that can present to almost any general or sub-specialty Ophthalmology practice. Its features classically involve anterior chamber cell and flare. Below the surface of these two signs exist a panoply of diagnoses. BODY: The purpose of this review is to provide a general framework for diagnoses of anterior uveitis that are often missed as well as non-uveitic pathologies that often mimic anterior uveitis. Diagnostic deviation in either direction can have vision-threatening and rarely life-threatening consequences for patients. Using a comprehensive literature review we have collected a broad spectrum of etiologies of anterior uveitis that are easily missed and non-uveitic pathologies that can masquerade as anterior uveitis.

CONCLUSIONS

We present a focused review on specific misdiagnosed anterior uveitis pathologies and some of the conditions that can masquerade as anterior uveitis and scleritis.

Risk factors of internal carotid artery stenosis in patients with proliferative diabetic retinopathy: an analysis using optical coherence tomography and optical coherence tomography angiography

BACKGROUND

This research investigates the correlation between the severity of internal carotid artery (ICA) stenosis and retinal parameters in patients with proliferative diabetic retinopathy (PDR), aiming to uncover potential risk factors.

METHODS

A retrospective analysis of 68 patients (136 eyes) diagnosed with bilateral PDR from January 1, 2017, to December 31, 2021, was conducted. Carotid artery stenosis (CAS) was assessed using neck computed tomography angiography (CTA) and carotid duplex ultrasound (CDUS), with stenosis classified into two groups: normal (group 1) and mild or above (group 2), based on the North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria. Optical coherence tomography (OCT) and OCT angiography (OCTA) measured several retinal parameters, including sub foveal choroidal thickness (SFCT), retinal nerve fiber layer (RNFL) thickness, ganglion cell-inner plexiform layer (GCIPL) thickness, vessel density (VD), and foveal avascular zone (FAZ) area. Statistical analyses determined correlations between ICA degrees and retinal parameters.

RESULTS

This study showed significant differences between groups in total VD, FAZ area, total RNFL thickness, and temporal RNFL thickness, indicating that patients with more severe ICA stenosis had noticeable retinal changes. Other parameters such as hyperlipidemia, total cholesterol levels, and intraocular pressure (IOP) also differed significantly, while no notable differences were observed in SFCT, central VD, average GCIPL, and superior, nasal, and inferior RNFL thickness.

CONCLUSION

The study findings highlight retinal changes, such as an increased FAZ area, decreased total VD, and a total and thinner temporal RNFL, which suggest the need for carotid artery evaluation in patients. These findings have important clinical implications for the need for carotid work up in patients with PDR.

Preoperative Ocular Symptoms Predict Acute Glaucoma After Carotid Revascularization: An Analysis of Combined Single-Center Data and a Systematic Review

BACKGROUND

Acute glaucoma is a potential complication of carotid revascularization procedures such as endarterectomy or stenting. Although preoperative ocular hypoperfusion may predispose patients to postoperative glaucoma, the details of this complication have not been clarified.

METHODS

We retrospectively reviewed the medical records of consecutive patients who underwent carotid revascularization at our institution from January 2019 to December 2022. These patients were divided into glaucoma and nonglaucoma groups. Given the rarity of the event, a systematic literature review was performed to additionally include data from patients who developed acute glaucoma after carotid revascularization. Multivariate logistic regression was performed to identify the risk factors for acute glaucoma.

RESULTS

Thirty-five cases, including 2 from our institution, were included in the glaucoma group, and 130 were included in the nonglaucoma group. Most cases (79%) occurred within five days postoperatively. Multivariate analysis revealed that preoperative ocular symptoms were significantly associated with the development of postoperative glaucoma (odds ratio, 361.06; 95% confidence interval, 34.09-3824.27; P < 0.001). Preoperative neovascularization at the iris or anterior chamber angle, indicating severe ocular hypoperfusion, was found in 84% of patients with glaucoma. Permanent visual loss occurred in 41% of patients. The incidence of postoperative glaucoma at our institution was 1.5% (2/132). The positive predictive value of preoperative ocular symptoms for postoperative glaucoma was 0.25 (95% confidence interval, 0.18-0.32).

CONCLUSIONS

This study was the first to clarify the risk factors and characteristics of acute glaucoma after carotid revascularization.

Ocular Ischemic Syndrome due to Internal Carotid Artery Occlusion with Neurofibromatosis Type 1

Neurofibromatosis type 1 (NF-1) is associated with multiple vascular abnormalities, including internal carotid artery (ICA) stenosis/occlusion. Depending on the site of stenosis/occlusion of the ICA, both cerebral circulation and ocular circulation can be impaired. We describe a rare pediatric case of ocular ischemic syndrome (OIS) due to ICA occlusion in NF-1. The patient diagnosed with NF-1 suffered right ICA occlusion at 12 years of age, and developed right dense vitreous hemorrhage due to OIS at 13 years of age. The patient underwent right cerebral revascularization surgery to improve cerebral and ocular ischemia, but the visual acuity of the right eye did not improve. This case suggests that attention should be paid not only to cerebral ischemia but also to ocular ischemia in patients with ICA stenosis/occlusion of NF-1. Surgical interventions such as cerebral revascularization surgery should be considered in the early stages of OIS to protect visual function, and careful follow-up is required.

Acute visual loss as the first ocular symptom in a Sjögren's syndrome patient with bilateral common carotid artery occlusion: a case report

Background

Sjögren’s syndrome may be a risk factor for carotid artery stenosis. Bilateral common carotid artery occlusion (BCCAO) in a patient with Sjögren’s syndrome was not reported before. In this report, we describe a female with Sjögren’s syndrome who had acute visual loss due to ocular ischemic syndrome (OIS) with BCCAO.

Case presentation

A 50-year-old female with Sjögren’s syndrome visited our clinic with acute visual loss in the left eye. The best corrected visual acuity (BCVA) was 2/100 in the left eye, and the intraocular pressure (IOP) was normal in both eyes. Ocular ischemic change was observed during the ophthalmic examination. Aortography and computed tomography angiography (CTA) showed nearly total occlusion of the bilateral CCA. Thus, OIS with BCCAO was diagnosed. The vision in the left eye improved to 30/100 after carotid artery stenting for the left common carotid artery.

Conclusions

BCCAO may be present in patients with Sjögren’s syndrome. Large vessel abnormalities should be considered when acute visual loss is found in a patient with Sjögren’s syndrome.

Clinical Significance of Choroidal Thickness in Eyes with Ocular Ischemic Syndrome

Purpose

To determine the clinical significance of choroidal thickness and evaluate changes in choroidal thickness over time in eyes affected by ocular ischemic syndrome (OIS).

Methods

Medical records of 16 patients diagnosed with OIS between November 2017 and August 2019 were retrospectively reviewed. In every nine areas of the Early Treatment Diabetic Retinopathy Study (ETDRS) grid, we compared the differences in choroidal thickness between the eyes with OIS and unaffected eyes, and its change in the OIS eyes during the follow-up period using swept-source optical coherence tomography. We analyzed the best corrected visual acuity (BCVA), intraocular pressure (IOP), fluorescein angiography (FAG) parameters, systemic diseases, and the duration of symptoms. Correlation between FAG parameters and the choroidal thickness value ratio in the OIS eyes and the unaffected eyes, and changes in the choroidal thickness in the OIS eyes during follow-up were investigated.

Results

Median age of the subjects was 67.5 years. In the OIS eyes, all FAG parameters were delayed at the initial examination. BCVA and IOP were significantly different between the IOS and unaffected eyes. While the choroidal thickness in every nine areas of ETDRS in the OIS eyes was lesser than the unaffected eyes, the choroidal thickness of inner temporal, outer nasal, and outer temporal area showed statistically significant difference. During follow-up, changes in choroidal thickness of OIS eyes as well as correlation between the FAG parameters and the choroidal thickness value ratio between the OIS eyes and the unaffected eyes were not found to be statistically significant.

Conclusions

The choroidal thickness of the eyes with OIS was significantly less compared with the unaffected eyes. We inferred that choroidal thinning takes place in the early phase of the disease as the changes in choroidal thickness during the follow-up period were not significant.

Ocular ischemic syndrome due to severe internal carotid artery stenosis improved by intracranial stent placement: A case report

Background:

Treatment of cervical internal carotid artery (ICA) stenosis has contributed to the improvement of ocular ischemic syndrome. However, there have been few cases of visual impairment caused by ocular ischemic syndrome due to intracranial ICA stenosis, which improved through intracranial stent placement.

Case Description:

A 76-year-old man presented with right-sided paralysis. Radiographic examination revealed severe stenosis of the left intracranial ICA (distal cavernous-infraclinoid portion) and a watershed infarction of the left cerebral hemisphere. Conservative therapy including antiplatelet drugs was initiated, but severe visual acuity disturbance in his left eye occurred 1 month after onset. The antegrade ocular artery flow recovered after urgent intracranial stent placement, and his vision improved immediately after the procedure.

Conclusion:

Visual impairment presenting as ocular ischemic syndrome can occur due to severe stenosis of the intracranial ICA, and treatment of these lesions could improve the symptoms.

Retinal dysfunction induced in a mouse model of unilateral common carotid artery occlusion

Background

Retinal ischemic stresses are associated with the pathogenesis of various retinal vascular diseases. To investigate pathological mechanisms of retinal ischemia, reproducible, robust and clinically significant experimental rodent models are highly needed. Previously, we established a stable murine model of chronic hypoperfusion retinal injuries by permanent unilateral common carotid artery occlusion (UCCAO) and demonstrated chronic pathological processes in the ischemic retina after the occlusion; however, retinal functional deficits and other acute retinal ischemic injuries by UCCAO still remain obscure. In this study, we attempted to examine retinal functional changes as well as acute retinal ischemic alterations such as retinal thinning, gliosis and cell death after UCCAO.

Methods

Adult mice (male C57BL/6, 6–8 weeks old) were subjected to UCCAO in the right side, and retinal function was primarily measured using electroretinography for 14 days after the surgery. Furthermore, retinal thinning, gliosis and cell death were investigated using optical coherence tomography, immunohistochemistry and TUNEL assay, respectively.

Results

Functional deficits in the unilateral right retina started to be seen 7 days after the occlusion. Specifically, the amplitude of b-wave dramatically decreased while that of a-wave was slightly affected. 14 days after the occlusion, the amplitudes of both waves and oscillatory potentials were significantly detected decreased in the unilateral right retina. Even though a change in retinal thickness was not dramatically observed among all the eyes, retinal gliosis and cell death in the unilateral right retina were substantially observed after UCCAO.

Conclusions

Along with previous retinal ischemic results in this model, UCCAO can stimulate retinal ischemia leading to functional, morphological and molecular changes in the retina. This model can be useful for the investigation of pathological mechanisms for human ischemic retinopathies and furthermore can be utilized to test new drugs for various ischemic ocular diseases.

Diagnosis and clinical course of ocular ischemic syndrome with retinal vascular abnormalities due to unilateral ocular artery and internal carotid artery stenosis in a child with neurofibromatosis type 1: a case report

Background

Neurofibromatosis type 1 (NF1) is a hereditary disease that causes neurofibromas generally, but it has been reported to sometimes be associated with various forms of blood vessel stenosis, occlusion and vascular abnormalities of unknown mechanism. However, a symptomatic case with simultaneous ophthalmic artery stenosis and internal carotid artery stenosis is an extremely rare pathogenesis in a child with NF1. In this report, we performed the diagnosis and observation using various imaging modalities for this rare pediatric case.

Case presentation

A 6-year-old girl diagnosed with NF1 presented with gradual visual loss in the right eye. Best corrected visual acuity (BCVA) was 20/40 OD and the intraocular pressure (IOP) was normal in both eyes. Retinal vascular abnormalities with tortuous vessels and optic disc pallor were observed in the right fundus. Widefield fluorescein angiography revealed multiple sites of neovascularization and a large non-perfusion area in the peripheral retina. Optical coherence tomography angiography showed retinal vascular abnormalities in the right eye and revealed differences in inner retinal thickness and blood flow signal between the left and right eyes. Laser speckle flowgraphy showed that chorioretinal blood flow was significantly decreased in the right eye. Cerebral angiography revealed the right ophthalmic artery was significantly narrowed throughout. In addition, Magnetic resonance angiography revealed that the right internal carotid artery was significantly narrowed in the ophthalmic segment. We diagnosed ophthalmic artery and internal carotid artery stenosis with retinal vascular abnormalities and ocular ischemic syndrome in NF1. Because IOP increased to 35 mmHg, due to neovascular glaucoma in addition to mild vitreous hemorrhage occurred, panretinal photocoagulation was performed after intravitreal bevacizumab injection. After treatments, IOP normalized, but BCVA decreased to 20/100 OD. Arterial spin labeling showed normal cerebral blood flow. The patient is currently being carefully monitored.

Conclusions

We have described the diagnosis and treatment of ocular ischemic syndrome due to multiple arteries stenosis in a child with NF 1. Utilization of various imaging modalities was helpful in diagnosing the complicated pathogenesis. However, since direct intervention by neurosurgery is not possible in this case, it is expected that treatment will be extremely difficult in the future.

[Ocular ischemic syndrome : An important differential diagnosis]

BACKGROUND

Ocular ischemic syndrome is a rare disease, which must be considered as a differential diagnosis in cases of painful loss of vision.

CASE REPORT

A 63-year-old male patient presented as an emergency in our consultation with hyphemia and decompensated intraocular pressure of the right eye. The right eye had been painful for 3 weeks. Apart from nicotine abuse, no relevant pre-existing medical conditions were known. With suspected iritis, the initial treatment was performed with eye drops containing a corticosteroid. After initial improvement in symptoms, an acute deterioration occurred with decrease in visual acuity and increased pain starting 2 days previously. Biomicroscopic examination revealed rubeosis iridis with hyphemia. Due to the hyphemia the view of the fundus was greatly reduced but there were no indications for retinal bleeding. In gonioscopy a chamber angle closure was evident. Fluorescence angiography showed a significantly longer arm-retina time, a delayed arteriovenous passage, peripheral vascular leaks and reduced fluorescence of the choroid. An ocular ischemic syndrome was suspected, therefore, duplex sonography of the carotid arteries and computed tomography angiography were performed and showed complete stenosis of the right internal carotid artery and moderate stenosis of the left internal carotid artery. An intravitreal administration of anti-VEGF and panretinal laser photocoagulation were carried out. Furthermore, an evaluation of the cardiovascular risk factors was initiated as part of the interdisciplinary investigation.

Risk of Stroke in Patients With Ocular Arterial Occlusive Disorders: A Retrospective Canadian Study

Background

Monocular vision loss, attributed to either central retinal artery occlusion (CRAO), branch retinal artery occlusion (BRAO), or ocular ischemic syndrome (OIS), is thought to be associated with an increased prevalence of cerebral infarcts. However, there is a paucity of data substantiating this. We aimed to investigate this relationship in a Canadian center and further understand the importance of associated internal carotid artery stenosis in potential clinical decision making.

Methods and Results

We performed a retrospective cohort study at a comprehensive stroke center of patients presenting initially with CRAO, BRAO, or OIS to a centralized ophthalmology center over a 5‐year period. Patients were followed for 3 years for the occurrence of a hemispheric stroke. We identified 83 affected eyes, with 31 CRAO, 35 BRAO, and 17 OIS patients. Before ocular diagnosis, 32.3%, 11.4%, and 41.2% of CRAO, BRAO, and OIS patients, respectively, experienced a symptomatic stroke. Of the remaining patients, 4.8%, 12.9%, and 40%, respectively, suffered a hemispheric stroke within 3 years of ocular diagnosis. Logistic regressions suggested that for CRAO and BRAO patients together, the degree of ipsilateral internal carotid artery stenosis is unable to predict the occurrence of a stroke (P=0.18), whereas our model correctly predicted a stroke in 82.4% of OIS patients (P=0.005).

Conclusions

CRAO, BRAO, and OIS are associated with significantly increased symptomatic stroke rates. Degree of ipsilateral internal carotid artery stenosis may not be useful in risk stratification for these patients, suggesting that they should be triaged appropriately for stroke risk‐factor management, independent of internal carotid artery stenosis.

Clinical Features of Ocular Ischemic Syndrome and Risk Factors for Neovascular Glaucoma

Purpose

We aimed to examine the clinical features and prognosis of ocular ischemic syndrome and to investigate the risk factors for the development of neovascular glaucoma (NVG).

Methods

The medical records from 25 patients (25 eyes) who were diagnosed with ocular ischemic syndrome were retrospectively analyzed. We recorded the length of time between symptom onset and diagnosis, visual acuity, intraocular pressure, clinical findings of the anterior and posterior segments of the eye, fluorescein angiography, systemic diseases, smoking history, and the extent of any ipsilateral carotid artery stenosis. The risk factors for NVG in patients with ocular ischemic syndrome were investigated.

Results

The mean age was 67.9 ± 12.5 years, and 21 men and 4 women were included in this study. At initial examination, the mean logarithm of the minimum angle of resolution (logMAR) was 2.02 ± 1.26, and the mean intraocular pressure was 21.0 ± 10.3 mmHg. Among 25 eyes of the 25 patients, NVG occurred in 17 eyes after a mean period of 12.6 ± 14.0 months. The length of time between symptom onset and diagnosis (p = 0.025) and the extent of ipsilateral carotid artery stenosis (p = 0.032) were identified as significant risk factors for NVG. At the final follow-up, the mean logMAR visual acuity was 3.13 ± 1.24, showing a poor prognosis regardless of whether NVG occurred.

Conclusions

Overall, the prognosis for ocular ischemic syndrome is very poor. The risk of NVG increases with the length of time between symptom onset and diagnosis, as well as with the severity of ipsilateral carotid artery stenosis.

Takayasu arteritis presenting as isolated anterior ischemic optic neuropathy

Takayasu arteritis (TA) is a systemic vasculitis of unknown etiology that affects the aorta and its primary branches or large arteries in the proximal upper or lower extremities. Ocular manifestations of TA include microaneurysm formation, small-vessel dilation, arteriovenous anastomosis, retinal ischemia, and neovascular glaucoma. We herein report a case involving a 23-year-old Asian woman who presented with isolated acute anterior ischemic optic neuropathy and was initially misdiagnosed with optic neuritis. The stenosis and occlusion of the aorta and other proximal arteries on angiography confirmed the diagnosis of TA.

A case of dry eye secondary to ocular ischemic syndrome due to carotid artery occlusion

A case of unilateral dry eye associated with ipsilateral carotid artery occlusion.

The kallikrein system in retinal damage/protection

Kallikrein is a serine protease involved in the kallikrein-kinnin system. Kallikrein is derived from the blood plasma or tissue, and is correlated with aggravation and improvement in eye diseases, such as, glaucoma, diabetic retinopathy, age-related macular degeneration, and ocular ischemic syndrome. The plasma kallikrein stimulates retinal vascular permeability and intraocular hemorrhage. On the other hand, we had reported that the tissue kallikrein normalizes retinal vasopermeability and inhibited retinal neovascularization and retinal ischemic injury. The protective mechanisms of the tissue-derived kallikrein include the cleavage of vascular endothelial growth factor (VEGF), which suggests that the tissue kallikrein could be potentially-effective against any disease involving the VEGF production.

Bilateral Ocular Ischaemic Syndrome-Rare Complication of Rhinocerebral Mucormycosis in an Omani Patient: Case report and literature review

Ocular ischaemic syndrome (OIS) is a relatively uncommon condition. Simultaneous bilateral involvement is even less common and has been reported in only 22% of all cases of OIS. It has variable clinical presentations, of which visual loss and ocular pain are the most common. It is believed to occur when there is a 90% or greater carotid artery obstruction. This syndrome is often associated with a number of systemic diseases including diabetes mellitus, hypertension, coronary artery disease, and cerebrovascular disease. Only occasionally has it been described as a complication of rhinocerebral mucormycosis. We report an unusual case of bilateral OIS secondary to bilateral internal carotid artery thrombosis as a complication of invasive rhinocerebral mucormycosis. In addition, a review of clinical presentation, diagnostic work-up and treatment options for OIS is provided.