Optical coherence tomography angiography in the diagnosis of ocular disease

Clinical imaging provided by optical coherence tomography (OCT) and its variant, OCT-angiography (OCT-A), has revolutionised eyecare practice. The imaging techniques allow for the identification and quantification of ocular structures, supporting the diagnosis and prognosis of eye disease. In this review, an overview of the usefulness of OCT-A imaging in the diagnosis and management of a range of ocular conditions is provided when used in isolation or in combination with other imaging modalities and measures of visual function (visual field results). OCT-A imaging has the capacity to identify and quantify ocular vasculature non-invasively, thereby assisting the clinician in the diagnosis or to determine the efficacy of intervention in ocular conditions impacting retinal vasculature. Thus, additional clinically useful information can be obtained in eye diseases involving conditions such as those impacting retinal vessel occlusion, in diabetic retinopathy, inherited retinal dystrophy, age-related macular degeneration, choroidal neovascularisation and optic nerve disorders. Through a clinical case series, various ocular conditions are reviewed, and the impact of OCT-A imaging is discussed. Although OCT-A imaging has great promise and is already used in clinical management, there is a lack of set standards to characterise altered vascular features in disease and consequently for prognostication, primarily due to a lack of large-scale clinical trials and variability in OCT-A algorithms when generating quantitative parameters.

Central Retinal Artery Occlusion in Young Adults at High Altitude: Thin Air, High Stakes

Rana, Vipin, Pradeep Kumar, Sandeepan Bandopadhyay, Vijay K. Sharma, Meenu Dangi, Dattakiran Joshi, Sanjay Kumar Mishra, Satyabrat Srikumar, and V.A. Arun. Central retinal artery occlusion in young adults at high altitude: thin air, high stakes. High Alt Med Biol. 00:000-000, 2024.-We present five cases of young security personnel who were posted at high altitude (HA) for a duration of at least 6 months and presented with a sudden decrease of vision in one eye. The diagnosis of central retinal artery occlusion (CRAO) was made in all patients. Fundus fluorescein angiography and optical coherence tomography of the macula supported the diagnosis. None of these cases had any preexisting comorbidities. Erythrocytosis was noticed in all patients, and two of them had hyperhomocysteinemia. Four out of five patients showed either middle cerebral artery or internal carotid artery (ICA) thrombosis on computed tomography angiography. The patients were managed by a team of ophthalmologist, hematologist, vascular surgeon, and neurologist. In cases of incomplete ICA occlusion, patients were managed surgically. However, in the case of complete ICA occlusion, management was conservative with antiplatelet drugs. This case series highlights HA-associated erythrocytosis and hyperhomocysteinemia as important risk factors for CRAO in young individuals stationed at HA.

Safety and effectiveness of IV Thrombolysis in retinal artery occlusion: A multicenter retrospective cohort study

BACKGROUND

Retinal artery occlusion (RAO) may lead to irreversible blindness. For acute RAO, intravenous thrombolysis (IVT) can be considered as treatment. However, due to the rarity of RAO, data about IVT safety and effectiveness is limited.

METHODS

From the multicenter database ThRombolysis for Ischemic Stroke Patients (TRISP), we retrospectively analyzed visual acuity (VA) at baseline and within 3 months in IVT and non-IVT treated RAO patients. Primary outcome was difference of VA between baseline and follow up (∆VA). Secondary outcomes were rates of visual recovery (defined as improvement of VA ⩾ 0.3 logMAR), and safety (symptomatic intracranial hemorrhage (sICH) according to ECASS II criteria, asymptomatic intracranial hemorrhage (ICH) and major extracranial bleeding). Statistical analysis was performed using parametric tests and a linear regression model adjusted for age, sex and baseline VA.

RESULTS

We screened 200 patients with acute RAO and included 47 IVT and 34 non-IVT patients with complete information about recovery of vision. Visual Acuity at follow up significantly improved compared to baseline in IVT patients (∆VA 0.5 ± 0.8, p < 0.001) and non-IVT patients (∆VA 0.40 ± 1.1, p < 0.05). No significant differences in ∆VA and visual recovery rate were found between groups at follow up. Two asymptomatic ICH (4%) and one (2%) major extracranial bleeding (intraocular bleeding) occurred in the IVT group, while no bleeding events were reported in the non-IVT group.

CONCLUSION

Our study provides real-life data from the largest cohort of IVT treated RAO patients published so far. While there is no evidence for superiority of IVT compared to conservative treatment, bleeding rates were low. A randomized controlled trial and standardized outcome assessments in RAO patients are justified to assess the net benefit of IVT in RAO.

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.

Correlation of Measurements From Doppler Ultrasound and Optical Coherence Tomography in Glaucoma

OBJECTIVES

To relate the changes in ocular structure and hemodynamic response in primary open-angle glaucoma (POAG).

METHODS

Patients with POAG (n = 46) and control subjects (n = 53) were recruited. Retinal nerve fiber layer and ganglion cell complex were evaluated using optical coherence tomography (OCT). Blood flow was characterized in ophthalmic artery (OA) and central retinal artery (CRA) using color Doppler ultrasonography (CDU), and resistivity index (RI) was calculated. Measurements from CDU and OCT were statistically correlated and the degree of the association was examined. Receiver operating characteristics was produced based on RI and optimal threshold was determined.

RESULTS

In POAG patients, OCT revealed neuronal damage and CDU indicated increased resistance to arterial flow. Flow dynamics correlated negatively with the ocular tissue dimensions, sufficiently establishing an association between the ocular structure and its hemodynamic response. Based on the possibility of indirect POAG diagnosis with CDU, threshold 0.7 for RI of OA yielded 73.9% sensitivity and 77.4% specificity in distinguishing the cases of POAG from the controls. Threshold of 0.66 for RI of CRA, had higher specificity of 83%, but lower sensitivity of 52.1%.

CONCLUSIONS

Ocular flow exhibits different characteristics in individuals with POAG than normal. The changes associated with the underlying neuronal structure, suggesting the possibility of a potential new diagnostic biomarker for POAG. This justifies further studies with a larger cohort, examining the ocular flow with CDU in POAG and comparing it against OCT findings for establishing the power of CDU in differential diagnosis or glaucoma progression.

Consensus Opinion for The Management of Soft Tissue Filler Induced Vision Loss

There are multiple treatment strategies proposed for the management of vision loss related to the injection of soft tissue fillers. Currently, there is no internationally accepted consensus on the immediate management of soft tissue filler induced vision loss (STFIVL). A recent systematic review of the literature concluded that there is not enough evidence to support retrobulbar hyaluronidase, and alternative treatments require exploration. The available literature demonstrates the inconsistent and unproven success of retrobulbar and peribulbar hyaluronidase in reversal of soft filler induced vision loss. Various therapeutics have been used to aid the reversal of vision loss but with mixed outcomes. The current evidence base does not support the use of retrobulbar and peribulbar hyaluronidase. The use of retrobulbar hyaluronidase for reversing soft tissue filler induced vision loss is controversial. Its efficacy remains unproven and there is mixed evidence within the literature. The current evidence suggests that there may be an increased risk of introducing severe adverse events associated with retrobulbar hyaluronidase and may even exacerbate the problem for those clinicians who are not ophthalmology trained. Therefore, we recommend two alternative treatment pathways for ophthalmology and non-ophthalmology trained practitioners. The suggested goal of this publication is to understand the pathophysiology of STFIVL, recognize signs and symptoms, and to propose algorithms to manage vision loss for both non-ophthalmology and ophthalmology trained clinicians. Clinicians must act swiftly and arrange immediate transfer to an emergency department or ophthalmology specialist setting to give the patient the best chance of vision restoration. The focus of any intervention for non-ophthalmology trained clinicians should be based around the immediate use of non-invasive techniques.

Acute central retinal artery occlusion: Proposed therapeutic approach for ocular stroke

Összefoglaló. Az agy és a szem vascularis katasztrófái számos esetben egymáshoz társuló vagy egymást előre jelző kórképek. Az arteria centralis retinae occlusio az ér rekanalizációjának hiányában a retina szöveteinek irreverzibilis károsodását okozza. Sem a nemzetközi, sem a hazai stroke-irányelvek nem foglalkoznak az ocularis stroke problémakörével, annak ellenére, hogy az arteria centralis retinae occlusio okozta retinalis ischaemia minden tekintetben megfelel az akut ischaemiás stroke definíciójának. Az eddig rendelkezésre álló irodalmi adatok alapján arteria centralis retinae occlusio esetén az intravénás thrombolysis 4,5 órán belül alkalmazva növeli a szignifikáns mértékű visusjavulás esélyét. Az országban jelenleg 4 centrum (Pécsi Tudományegyetem, Szegedi Tudományegyetem, Debreceni Egyetem, Semmelweis Egyetem) tervezi az ocularis stroke kezelésében a thrombolysis bevezetését. A maradandó látásromlás és a szekunder cerebrovascularis események megelőzése érdekében elengedhetetlen az alapellátásban és a társszakmákban dolgozó kollégákkal való szoros együttműködés. Orv Hetil. 2021; 162(47): 1871-1875. Summary. Vascular events of the brain and the eye may occur concomitantly or sequentially. In the absence of recanalization, central retinal artery occlusion causes irreversible damage to the retinal tissues. Even though retinal ischemia secondary to central retinal artery occlusion meets the definition of acute ischemic stroke, neither the international nor the Hungarian stroke guidelines mention ocular stroke. Based on the available literature, intravenous thrombolysis of the central retinal artery within 4.5 hours of occlusion can increase the odds of significant vision improvement. Currently 4 centers (University of Pécs, Debrecen, Szeged, and Semmelweis University) are planning to introduce thrombolysis in the treatment of ocular stroke. To prevent permanent visual loss and secondary cerebrovascular events, timely intervention requires the collaboration between general practitioners and other specialties. Orv Hetil. 2021; 162(47): 1871-1875.

Vitrectomy and manipulation of intraocular and arterial pressures for the treatment of nonarteritic central retinal artery occlusion

The purpose of this study is to describe a surgical technique and report the functional outcome of treating nonarteritic central retinal artery occlusion (CRAO) in 2 eyes of two consecutive male patients. Two males (A) and (B) presented 6 days and few hours, respectively, after symptom onset with the clinical features typical of CRAO, including sudden severe deterioration of vision to counting fingers and a cherry-red spot in the left and right fovea, respectively. While A had been on recent treatment for hypertension and hyperlipidemia, B had no significant medical history. Both patients underwent surgery, A, 9 days, and B, <15 h after symptom onset. Surgery involved a vitrectomy, lowering of intraocular pressure (<3 mmHg), and gradual increase of arterial pressure to 165/100 mmHg (through the slow injection of intravenous adrenaline). Intraoperatively, this resulted in immediate perfusion and visible dilation of the blood-filled central retinal artery (CRA) and retinal arteriolar network and dilatation of the central retinal vein. The final vision settled to 6/60 in A and 6/36+1 in B. Although preoperative macular infarction persisted in both eyes as demonstrated by optical coherence tomography angiography, both patients claim a convincing subjective visual benefit. The procedure appeared to have positively changed the natural history of the disease in both eyes. Vitrectomy with the manipulation of intraocular and arterial pressures significantly increases ocular perfusion along the entire CRA, which can dislodge CRA thrombo-emboli and has the potential to restore retinal perfusion and improve visual outcome if undertaken before irreversible retina damage. This is a relatively straightforward technique and should join the list of surgical techniques for treating CRAO.

Evaluation of ultrasonographic optic nerve sheath diameter and central retinal artery Doppler indices by point-of-care ultrasound in pediatric patients with increased intracranial pressure

BACKGROUND

Measurement of the optic nerve sheath diameter (ONSD) with point-of-care ultrasound (POCUS) is a non-invasive and radiation-free technique that can be used to assess increased intracranial pressure (ICP). Ophthalmic artery and central retinal artery Doppler indices can be used like transcranial Doppler to evaluate increased ICP. This study aims to examine the diagnostic value of ONSD measurements and central retinal artery Doppler indices in the evaluation of pediatric patients with increased ICP.

METHODS

This was a prospective, case-controlled single center study. The study group was comprised of a total of 38 pediatric patients with increased ICP and the control group included 19 healthy children. Ophthalmic ultrasound was performed and ONSD and central retinal artery Doppler indices were measured.

RESULTS

The mean age of the study group was 80.84 ± 65.12 months. The mean ONSD was 5.9 ± 0.8 (3.6-8.1) mm in the study group and the mean resistive index (RI) was 0.71 ± 0.08 (min:0,55-max:1) and was significantly greater than the control group (p < 0.001 and p < 0.001, respectively). In terms of predicting increased ICP, the ONSD measurement was the strongest parameter, with its area under the curve: 0.767 (95 percent confidence interval: 0.68-0.85). In the study group, the cut-off value for ONSD was 5.8 mm (66 percent sensitivity, 100 percent specificity) and the cut-off value for RI was 0.68 (63 percent sensitivity, 83 percent specificity).

CONCLUSIONS

Point-of-care ultrasound is a noninvasive and important tool in pediatric intensive care units. Our study is significant as one of the few pediatric studies where central retinal artery Doppler indices are evaluated in addition to OSND, in patients with increased ICP.

Impact of Radioiodine Treatment on Doppler Flow Parameters in the Central Retinal Artery and Ophthalmic Artery in Patients With Hyperthyroidism

OBJECTIVES

The aim of this study was to identify changes in Doppler flow parameters in the central retinal artery (CRA) and ophthalmic artery (OA) that could be indicative of de novo development of thyroid-associated orbitopathy in the early period after radioiodine treatment.

METHODS

Eighty-two patients with hyperthyroidism were enrolled: 44 with Graves disease and 38 with toxic nodular goiter. In both groups, blood flow parameters in the CRA and OA were analyzed before and 2 and 4 weeks after radioiodine administration. The peak systolic velocity and end-diastolic velocity (EDV) were evaluated, and the resistive index (RI) was calculated.

RESULTS

There were no statistically significant differences in the peak systolic velocity, EDV or RI between groups at baseline and 4 weeks after radioiodine administration. Two weeks after radioiodine administration, the RI in the CRA (P = .034) and EDV in the OA (P = .026) were significantly lower, and the EDV in the CRA (P = .004) was higher in patients with Graves disease than in patients with toxic nodular goiter. There was an inverse correlation between baseline thyrotropin receptor autoantibody (TRAb) levels and the difference between the RI at weeks 4 and 2 (RI3-RI2) in the CRA (r = -0.458; P < .05) and a positive correlation between the baseline anti-thyroid peroxidase antibody concentration and RI3-RI2 in the OA (r = 0.435; P < .05).

CONCLUSIONS

Administration of radioiodine results in more prominent features of hyperkinetic circulation. Patients with Graves disease and high TRAb titers have a lower sensitivity to radioiodine treatment. High TRAb titers suggest higher disease activity and a weaker therapeutic effect of radioiodine.

The entry point of the central retinal artery into the outer meningeal sheath of the optic nerve

INTRODUCTION

The entry point of the central retinal artery (CRA) into the outer meningeal sheath of the optic nerve posterior to the globe has been studied and debated for more than one hundred years. The authors have supervised an orbital anatomy course for more than two decades. This article summarizes previous studies of the CRA and presents the results of dissections of 67 orbits.

MATERIALS AND METHODS

Heads were hemisected prior to dissection at the Vagelos College of Physicians and Surgeons of Columbia University. The authors measured the entry point of the CRA with a caliper and noted the meridional orientation of the CRA.

RESULTS

The mean entry point was 10.65 mm posterior to the globe, with a range of 5 to 18 mm. Most commonly, the CRA entered the sheath in the inferior meridian, but some entered slightly inferomedially or inferolaterally.

CONCLUSIONS

The entry point of the CRA into the sheath of the optic nerve is variable, and without detailed angiography the clinician cannot know the course of the CRA prior to performing invasive intraorbital procedures. Knowledge of common variations in CRA entry into the outer meningeal sheath of the optic nerve should help to minimize injury during surgery.

Treatment of Periorbital and Palpebral Arteriovenous Malformations

Objectives: To clarify clinically challenging palpebral arteriovenous malformations (AVMs) and to propose a novel therapeutic modality, we developed a multi-disciplinary approach for the management of AVMs with ulcer. Approach: First, the central retinal artery was secured with embolization by the transophthalmic arterial, a terminal branch of the internal carotid artery (ICA), and then, the branches of the external carotid artery (ECA) were embolized to cause a response in the AVM vasculature followed by sclerotherapy and surgery. Results: Over a 3-year follow-up of palpebral and periorbital AVMs in four females and one male 20 to 50 years of age with a mean age of 38 years, complete remission of the lesions were seen with no major complication, such as blindness, ptosis, or cerebral infarction, with functionally sound and esthetically acceptable results, with no recurrence or worsening even with one case of ulceration postembolization. Innovation: Planned treatment of palpebral and periorbital AVMs, which have been often left untreated because of their complex vasculature and a risk of total blindness due to occlusion of the central retinal artery. A "wait-and-watch" approach is frequently taken. It is important to secure the periphery to the bifurcation of the central retinal artery of the ICA, and then, embolization through the ECA results in complete remission of the lesion, followed by sclerotherapy and surgery, which are successful both in terms of function and esthetics. Conclusion: First, securing the central retinal artery leads to safer and complete resolution of palpebral and periorbital AVMs; wounding or therapeutic complications such as skin necrosis may be seen, but this approach results in complete remission in 3 years with no major complications.

A case report of isolated orbital vasculitis mimicking retinal migraine: A potential cause of recurrent transient monocular blindness and ipsilateral headache

BACKGROUND

Retinal migraine is an important differential diagnosis of recurrent transient monocular blindness accompanied by headache when other etiologies are excluded. Here, we report a case of orbital vasculitis which initially mimicked retinal migraine.

CASE REPORT

A 47-year-old woman had recurrent episodes of fully reversible transient monocular blindness accompanied by ipsilateral headache for 15 months. The patient's neuroimaging and cardiac and ophthalmologic evaluations were normal. With a diagnosis of retinal migraine, her symptoms remitted in response to prophylactic treatment with topiramate and propranolol for 8 months. Three months after discontinuation of medications, transient monocular blindness recurred. High-resolution vessel wall magnetic resonance imaging revealed enhancement of the ipsilateral orbital vessels. Isolated orbital vasculitis was diagnosed. Complete remission of transient monocular blindness was achieved after steroid pulse therapy.

DISCUSSION

Isolated orbital vasculitis should be considered in differential diagnosis of recurrent transient monocular blindness and ipsilateral headache. High-resolution vessel wall magnetic resonance imaging can be helpful for the diagnosis.

Treatment of Nonarteritic Acute Central Retinal Artery Occlusion

Central retinal artery occlusion (CRAO) is an event most often caused by an embolus originating in the ipsilateral carotid artery, aortic arch, or heart. CRAO may result from partial or complete occlusion of the central retinal artery (CRA), which acts as the primary blood supply to the inner neurosensory retina, and typically results in profound vision loss and permanent visual disability. No consensus has emerged regarding the optimal treatment of CRAO. All proposed treatments are of questionable efficacy and many have uncertain risk profiles. In certain circumstances, thrombolysis may be attempted as a treatment option; however, the evidence to support broad use of thrombolytics in the treatment of acute CRAO remains elusive. It is known that the risk factors that predispose to other cardiovascular and cerebrovascular events are often present in CRAO. Accordingly, identification of patients at highest risk of stroke and secondary prevention of ischemic events remains the primary focus of management. This review offers a summary of the clinical presentation, diagnosis, and prognosis of CRAO, with an emphasis on treatment options.

Reduced Central Retinal Artery Blood Flow Is Related to Impaired Central Visual Function in Retinitis Pigmentosa Patients

PURPOSE

We evaluated the test-retest repeatability of blood flow velocities in the retrobulbar central retinal artery (CRA) and explored whether reduced blood flow is related to the degree of visual function loss in retinitis pigmentosa (RP) patients with wide range of disease severity.

MATERIALS AND METHODS

We measured CRA peak systolic velocity (PSV) and end diastolic velocity (EDV) to calculate mean flow velocity (MFV) in 18 RP patients using color Doppler imaging with spectral flow Doppler (GE Logiq7 ultrasound) twice in each eye at each of two visits within a month. At each of these two visits, we measured ETDRS visual acuity (VA), quick Contrast Sensitivity Function (qCSF), Goldmann visual fields (GVF), 10-2 Humphrey visual fields (HVF), and dark-adaptation at 5° from fixation with the AdaptDx; multifocal electroretinography (mfERG) was obtained at a single visit.

RESULTS

Mean coefficients of variation for PSV, EDV and MFV were 16.1-19.2% for within-visit measurements and 20.1-22.4% for between-visit measures. Across patients, greater visual function loss assessed with VA (p = 0.04), extinguished versus measurable amplitude in ring 1 for mfERG (p = 0.001), and cone-only versus rod function with the AdaptDx (p = 0.002) were statistically significantly correlated with reduced MFV in the CRA when included a multilevel multivariate regression model along with the qCSF and HVF results, which all together accounted for 47% of the total variance in MFV. GVF log retinal areas (V4e and III4e; p = 0.30 and p = 0.95, respectively) and measurable far peripheral vision during GVF testing (p = 0.66) were not significantly related to MFV.

CONCLUSIONS

MFV in the CRA decreased with impaired central vision due to loss of both rod and cone function, had good test-retest repeatability, and may serve as a biomarker outcome to determine the potential physiological basis for improvements in RP clinical trials of therapies with indirect effects on blood flow to the retina.

Fusiform Left Carotid-Ophthalmic Artery Aneurysm Presenting with Central Retinal Artery Occlusion

Central retinal artery occlusion (CRAO) is a devastating ocular emergency characterized by acute painless visual loss in the ipsilateral eye. We describe the case of acute non-arteritic CRAO associated fusiform internal carotid-ophthalmic artery aneurysm with intraluminal thrombus. Despite the rarity of this condition, we suggest that carotid-ophthalmic artery aneurysm should be included in the differential diagnosis of CRAO.

Neuropathy optic glaucomatosa induced by systemic hypertension through activation endothelin-1 signaling pathway in central retinal artery in rats

AIM

To evaluate effect of hypertension on retinal ganglion cell (RGC) apoptosis, intraocular pressure (IOP), and the activation of endothelin-1 (ET-1) signaling pathway in central retinal artery (CRA) in rats.

METHODS

The experimental study was performed on 20 male Sprague Dawley rats that were divided into control group, and hypertension groups. The hypertension was induced by subcutaneous deoxycorticoacetate (DOCA) 10 mg/kg twice a week and administered 0.9% NaCl solution daily for 2, 6, and 10wk. Blood pressure (BP) was measured using animal BP analyzer. IOP was measured by handheld tonometry. Retinal tissue preparations by paraffin blocks were made after enucleation. The expression of ET-1, eNOS, ET-1 receptor A (ETR_A), ET-1 receptor B (ETR_B), and phosphorylated myosin light chain kinase (MLCK), and caldesmon (CaD) in CRA and RGC apoptosis were evaluated through immunofluorescent staining method then observed using laser scanning confocal microscopy.

RESULTS

BP significantly increased in all of the hypertension groups compared to control (P=0.001). Peak IOP elevation (7.78±4.14 mm Hg) and RGC apoptosis (576.15±33.28 Au) occurred on 2wk of hypertension. ET-1 expression (1238.6±55.1 Au) and eNOS expression (2814.2±70.7 Au) were found highest in 2wk of hypertension, although the ratio of ET-1/eNOS decreased since 2wk. ETR_A reached peak expression in 10wk of hypertension (1219.4±6.3 Au), while ETR_B significantly increased only in 2 weeks group (1069.2±9.6 Au). The highest MLCK expression (1190.09±58.32 Au), CaD (1670.28±18.36 Au) were also found in 2wk of hypertension.

CONCLUSION

Hypertension effects to activation of ET-1 signaling pathway significantly in CRA, elevation of IOP, and RGC apoptosis. The highest value was achieved at 2wk, which is the development phase of hypertension.

Central Retinal Artery Occlusion after the Endovascular Treatment of Unruptured Ophthalmic Artery Aneurysm: A Case Report and a Literature Review

Endovascular coil embolization for ophthalmic artery (OphA) aneurysms has a risk of occlusion of the OphA, which can lead to loss of vision. The authors report a patient with unruptured OphA aneurysm which treated with endovascular coiling and were complicated by blindness due to OphA thromboembolic occlusion after the procedure. The OphA successfully recanalized using local intra-arterial fibrinolysis with complete regain of visual acuity. The risk of visual loss due to thromboembolic complications cannot be ignored during endovascular coiling of the OphA aneurysm despite of good retrograde flow during OphA occlusion test using a balloon catheter. Rapid intervention is required for recovering visual disturbance in such a situation.

Evaluation of retrobulbar blood flow with color doppler ultrasonography in patients with central serous chorioretinopathy

BACKGROUND

To compare retrobulbar blood flow in patients with central serous chorioretinopathy (CSC) and healthy subjects using color Doppler ultrasonography.

METHODS

Thirty patients (age 23-54 years) with a first episode of acute CSC and 30 healthy controls (age 30-44 years) were evaluated. The peak systolic blood flow velocity, end-diastolic velocity (EDV), resistance index (RI), and pulsatility index (PI) were measured in the ophthalmic, posterior ciliary, and central retinal arteries.

RESULTS

The posterior ciliary and central retinal artery EDV were lower in the patient group than in the control group, whereas RI and PI values were significantly higher (p < .05). The ophthalmic artery peak systolic blood flow velocity and EDV were lower in the CSC than in the control group (p < .05) without significant difference in RI and PI.

CONCLUSIONS

Color Doppler ultrasonography provides additional insights into the pathophysiology of CSC and may support the vasospasm hypothesis.

Ultrasound assessment of ocular vascular effects of repeated intravitreal injections of ranibizumab for wet age-related macular degeneration

PURPOSE

Determine the effect of repeated intravitreal injections of ranibizumab (0.5 mg; 0.05 ml) on retrobulbar blood flow velocities (BFVs) using ultrasound imaging quantification in twenty patients with exudative age-related macular degeneration treated for 6 months.

METHODS

Visual acuity (ETDRS), central macular thickness (OCT), peak-systolic, end-diastolic and mean-BFVs in central retinal (CRA), temporal posterior ciliary (TPCA) and ophthalmic (OA) arteries were measured before, 2 days, 3 weeks and 6 months after the first injection. Patients were examined monthly and received 1-5 additional injections depending on ophthalmologic examination results.

RESULTS

Six months after the first injection, a significant increase in visual acuity 50.9 ± 25.9 versus 44.4 ± 21.7 (p < 0.01) and decrease in mean central macular thickness 267 ± 74 versus 377 ± 115 μm (p < 0.001) were observed compared to baseline. Although mean-BFVs decreased by 16%±3% in CRA and 20%±5% in TPCA (p < 0.001) 2 days after the first injection, no significant change was seen thereafter. Mean-BFVs in OA decreased by 19%±5% at week 3 (p < 0.001). However, the smallest number of injections (two injections) was associated with the longest time interval between the last injection and month 6 (20 weeks) and with the best return to baseline levels for mean-BFVs in CRA, suggesting that ranibizumab had reversible effects on native retinal vascular supply after its discontinuation. Moreover, a significant correlation between the number of injections and percentage of changes in mean-BFVs in CRA was observed at month 6 (R = 0.74, p < 0.001) unlike TPCA or OA.

CONCLUSION

Ranibizumab could impair the native choroidal and retinal vascular networks, but its effect seems reversible after its discontinuation.

A histological investigation into the correlation of central retinal artery atherosclerosis with the systemic circulation

Current research suggests that retinal arterial changes such as arteriovenous nicking and arterial narrowing are pathologically distinct from atherosclerosis. Other studies have found a positive correlation between retinal changes and systemic atherosclerosis. However, limited recent histopathologic evidence assessing atherosclerosis in the central retinal artery exists. We investigated atherosclerosis in the central retinal artery and how it correlates to atherosclerosis in the carotid and coronary arteries. Twenty-two cadavers (12 males, 10 females) were dissected, obtaining one orbit, one carotid artery, and one coronary artery from each. The specimens were sectioned and stained for histologic analysis by light microscopy using hematoxylin and eosin, Verhoeff's elastic, and Gomori's trichrome stains. The degree of atherosclerosis was graded from absent, or I (least severe) to VIII (most severe) based on the current American Heart Association guidelines. Atherosclerotic changes were present in the central retinal, coronary, and carotid arteries. A positive correlation was found between the central retinal artery and the carotid artery (r = 0.23, P = 0.15), the central retinal artery and the coronary artery (r = 0.31, P = 0.08), and the carotid artery and the coronary artery (r = 0.45, P = 0.02). The presence of low-grade atherosclerosis in the central retinal artery is prevalent in a population of advanced vascular disease. However, central retinal artery atherosclerotic lesion severity is poorly correlated with disease severity in the carotid and coronary arteries.

Low endogenous recanalization in embolic central retinal artery occlusion--the retrobulbar "spot sign"

BACKGROUND AND PURPOSE

Central retinal artery occlusion (CRAO) is most often indirectly diagnosed by lack of retinal perfusion. Direct embolus characterization may help to understand the natural course and low response to treatment. In a previous study we identified a hyperechoic signal within the optic nerve and in the central retinal artery ("spot sign").

METHODS

In this study we performed a follow-up investigation in 7 patients with CRAO and positive spot sign indicating the embolic cause of the occlusion after a median interval of 17 months (range 11-38 months) using a battery of tests (ocular color-coded sonography, optic coherence tomography [OCT], fundoscopy, amongst others).

RESULTS

The spot sign persisted in all patients, none had high-grade internal carotid artery stenosis, stroke or transient ischemic attacks. Four patients were completely blind, 3 patients were able to recognize hand movements. OCT demonstrated retinal atrophy, and fundoscopy revealed only minimal arterial perfusion.

CONCLUSIONS

The hyperechoic spot sign may be an important predictive prognostic marker for persistent loss of vision. Its persistence may indicate calcified or cholesterol emboli and may explain the low therapeutic success rate to thrombolysis. Further studies on their origin and significance in atherosclerotic disease are warranted.

Monitoring of central retinal artery and vein with color Doppler ultrasound during heart surgery as an alternative to transcranial Doppler ultrasonography: a case report

Cardiac surgery can have severe neurologic complications. The noninvasive monitoring of intracranial circulation during heart surgery is usually performed with transcranial Doppler ultrasonography. We present the case of a 66-year-old man who underwent elective cardiac surgery for aortic valve replacement and coronary artery bypass graft, in whom monitoring was performed by simultaneously assessing blood flow velocity in the central retinal artery and vein.

Effects of bisoprolol and cilazapril on the central retinal artery blood flow in patients with essential hypertension--preliminary results

BACKGROUND

A growing body of evidence suggests that effective blood pressure reduction may inhibit the progression of microvascular damage in patients with essential arterial hypertension. However, the potential influence of anti-hypertensive drugs on ocular circulation has not been studied sufficiently.

PURPOSE

The aim of our study was to evaluate the effects of anti-hypertensive therapy on blood flow in the central retinal artery in patients with systemic arterial hypertension.

MATERIAL AND METHODS

Twenty patients with essential arterial hypertension, aged 32-46 years, were examined with Doppler ultrasonography (10 MHz ultrasound probe). Blood flow velocities, pulsatility, and vascular resistance were determined before and 3 hours after systemic application of either bisoprolol 5 mg or cilazapril 2.5 mg.

RESULTS

Administered bisoprolol significantly decreased maximum (9.8 ± 0.5 cm/s versus 8.5 ± 0.6 cm/s; P < 0.05) and minimum (2.75 ± 0.19 cm/s versus 1.75 ± 0.27 cm/s; P < 0.02) velocity, increased the Pourcellot's index (0.71 to 0.79; P < 0.05) in central retinal artery. There were no statistically significant changes in central retinal artery blood flow after administration of cilazapril.

CONCLUSION

Systemic application of beta-blockers may unfavourably disturb the ocular blood flow.