Idiopathic recurrent branch retinal arterial occlusion. Natural history and laboratory evaluation

Fluorescein Angiography as a Surrogate Marker of Disease Activity in Susac Syndrome

OBJECTIVES

To evaluate the sensitivity of fluorescein angiography (FA) in detecting disease activity in Susac syndrome.

METHODS

We conducted a blinded analysis of all FA, brain MRI, and audiogram examinations performed throughout the follow-up of patients with Susac syndrome.

RESULTS

A total of 79 FA examinations, 85 brain MRI scans, and 49 audiograms were analyzed from 9 patients followed for a mean (SD) period of 6 (4) years. Disease activity was detected in 41.5% of FA examinations, 10.5% of MRI scans, and 25% of audiograms (FA vs MRI, p < 0.0001; FA vs audiogram, p = 0.06; audiogram vs MRI, p < 0.05). Within 3 months of clinical relapses, activity was observed in 57%, 24%, and 27% of FA, MRI, and audiogram examinations, respectively (FA vs MRI, p < 0.05; FA vs audiogram, p = 0.09; audiogram vs MRI, p = 1). Quantitative analysis of FA showed a mean (SD) of 2.5 (2.5) leakages (both eyes) during relapses compared with 1.2 (1.4) during remission (p < 0.05).

DISCUSSION

FA, particularly arterial leakage, demonstrated the highest sensitivity in detecting disease activity and may be a valuable tool for treatment management in Susac syndrome. Future studies with larger samples should aim to identify the optimal threshold of FA changes associated with an increased risk of relapse.

Diagnostic and therapeutic complexity of Susac syndrome

A 40-year-old man who attended the emergency department with a scotoma in right eye. He mentioned hearing difficulties and headache for months and he had sensory and motor deficits in the previous days. In the ophthalmic examination, the right eye had areas of arterial occlusion. MRI revealed hyperintense lesions. The patient was diagnosed with Susac syndrome. He was treated with systemic steroids, however, it was not enough to control the condition. Rituximab and intravenous immunoglobulins were added, which allowed the improvement of neurological symptoms, but the alteration of the visual field and the hearing defect did not recover. Early diagnosis of this pathology is essential, since delaying treatment can cause irreversible consequences. Sometimes it is difficult given the wide variety of symptoms and the course of the disease. Ocular manifestations may raise suspicion when the general symptoms are nonspecific.

A Comprehensive Update on Retinal Vasculitis: Etiologies, Manifestations and Treatments

Retinal vasculitis is characterized by inflammatory involvement of retinal arterioles, venules and/or capillaries and can be associated with a myriad of systemic and ophthalmic diseases. In this review, we have comprehensively discussed the etiologies, clinical manifestations, and presentations of retinal vasculitis. We have also included newer advances in imaging in retinal vasculitis such as OCTA and widefield imaging.

RECURRENT BRANCH RETINAL ARTERY OCCLUSION FROM SUSAC SYNDROME: CASE REPORT AND REVIEW OF LITERATURE

PURPOSE

We report a patient with branch retinal artery occlusion predominant Susac syndrome and review the literature on current diagnostic modalities and therapeutic approaches for this rare condition.

METHODS

Case report.

RESULTS

A 23-year-old white male presented with a 5-month history of a scotoma in his right eye vision, headaches, and intermittent paresthesias of the lower extremities. Ophthalmic examination was normal with the exception of a hypopigmented small retinal area inferonasal to the fovea in the right eye. Optical coherence tomography demonstrated inner retinal atrophy and optical coherence tomography angiography showed deep capillary layer vessel dropout in both eyes. Ultra-wide-field fluorescein angiography revealed bilateral arteriolar wall hyperfluorescence. Corpus callosal lesions were present on magnetic resonance imaging. Lumbar puncture demonstrated elevated protein. Audiogram was normal. A diagnosis of Susac syndrome was made. The patient initially received oral steroids followed by intravenous steroids and mycophenolate mofetil because of new branch retinal artery occlusions. Thirteen months after initial presentation, the vision was stable at 20/20 in both eyes.

CONCLUSION

It is a diagnostic challenge when recurrent branch retinal artery occlusion secondary to Susac syndrome presents without the classic symptoms. Optical coherence tomography angiography and subtle magnetic resonance imaging findings aided in early recognition of the diagnosis in our patient. Ultra-wide-field fluorescein angiography was an important tool in disease monitoring. Aggressive management with intravenous corticosteroids and initiation of immunosuppression resulted in long-term preservation of vision and improvement in visual field.

Idiopathic retinal arterial occlusive vasculitis in the setting of multiple arterial occlusions

Purpose

We present a patient with vaso-occlusive retinal vasculitis to summarize this uncommon entity and review the clinical features and management challenges applicable to patients with retinal vasculitis.

Observations

A 76-year-old male presented with sudden-onset severe central vision loss. On examination, vitreous hemorrhage, neovascularization of the optic nerve, peripheral segmental periphlebitis, vessel sclerosis, vascular sheathing, and retinal hemorrhages were observed, and a diagnosis of active vaso-occlusive retinal vasculitis was made. The patient then underwent a complete infectious, inflammatory, and neoplastic workup which returned negative. The patient was treated with locally with a sub-Tenon's injection of 40 mg triamcinolone on presentation and later with oral prednisone. At three-month follow-up, vision improved to 20/300 with regressing neovascularization and clearing of vitreous hemorrhage in the right eye (OD).

Conclusions

Considering novel associations of occlusive retinal vasculitis, it is important to recognize that idiopathic occlusive retinal vasculitis, although uncommon, can occur and represents a prototypical disease form. It is imperative that these patients have a complete infectious, inflammatory, and neoplastic workup owing to the possible overlap of masquerade clinical signs and symptoms.

Diagnostic Criteria and Treatment Algorithm for Susac Syndrome

BACKGROUND

Susac syndrome (SS) classically presents with the clinical triad of retinal artery occlusion, sensorineural hearing loss, and encephalopathy and the neuroimaging triad of white matter lesions, deep gray matter lesions, and leptomeningeal disease. However, patients can present with an incomplete clinical or neuroimaging triads making diagnosis difficult in certain situations. A standard treatment paradigm also is lacking in this illness. It is important for neuro-ophthalmologists to recognize clinical and radiographic findings that are pathognomonic for this syndrome and have a basic understanding of the available treatment options.

EVIDENCE ACQUISITION

Review of medical literature.

RESULTS

A definite diagnosis of SS is made when the clinical triad or the neuroimaging triad is present. There are numerous reports of 2 other imaging findings in this condition: arteriolar wall hyperfluorescence (AWH) on fluorescein angiography in retinal arterioles remote from retinal ischemia and central callosal lesions on MRI. Both of these imaging findings are diagnostic of SS. Gass plaques in retinal arterioles are almost always seen in the acute phase of the illness but are not pathognomonic for SS. The most common medications used in this syndrome are corticosteroids and intravenous immunoglobulin. A number of other medications have been used including mycopheolate, rituximab, azathioprine, and cyclophosphamide.

CONCLUSIONS

In the absence of the clinical triad or magnetic resonance imaging triad for SS, AWH remote from retinal vascular injury and central callosal lesions are confirmatory of the diagnosis because they have never been described in any other condition. The presence of Gass plaques in retinal arterioles should strongly suggest the diagnosis. Despite the lack of clinical trial data, patients with SS must be treated promptly and aggressively. In more fulminant cases, addition of mycophenolate mofetil or rituximab is required, followed by cyclophosphamide when disease is refractory to other medications.

Migration of segmental arteriolar fluorescein staining peripherally in eye with idiopathic recurrent branch retinal arterial occlusion

Purpose

To report a novel finding in a case of idiopathic recurrent branch retinal arterial occlusions.

Observations

We report our findings in a 31-year-old woman with an idiopathic recurrent branch retinal arterial occlusions (BRAOs) who was followed in our clinic for 16 years. Repeated fluorescein angiographies were performed to evaluate the idiopathic recurrent BRAOs. The findings showed multiple segmental arteriolar staining in the fundus. These staining were found at locations with and without branch retinal arterial occlusions. Repeated fluorescein angiography showed that these staining migrated toward the periphery. The speed of the migration of the staining was about 0.64 ± 0.22 mm/day with a range of 0.43–0.85 mm/day in the posterior pole of the eye. In each of the BRAO, the staining did not cause branch retinal arterial occlusions in the peripheral retina again.

Conclusions and importance

Segmental arteriolar staining that migrates towards the periphery may be a clue to the etiology of this disease process.

Embolic Strokes of Unknown Source and Cryptogenic Stroke: Implications in Clinical Practice

Up to a third of strokes are rendered cryptogenic or of undetermined etiology. This number is specifically higher in younger patients. At times, inadequate diagnostic workups, multiple causes, or an under-recognized etiology contributes to this statistic. Embolic stroke of undetermined source, a new clinical entity particularly refers to patients with embolic stroke for whom the etiology of embolism remains unidentified despite through investigations ruling out established cardiac and vascular sources. In this article, we review current classification and discuss important clinical considerations in these patients; highlighting cardiac arrhythmias and structural abnormalities, patent foramen ovale, paradoxical sources, and potentially under-recognized, vascular, inflammatory, autoimmune, and hematologic sources in relation to clinical practice.

Differential diagnosis of retinal vasculitis

Retinal vaculitis is a sight-threatening inflammatory eye condition that involves the retinal vessels. Detection of retinal vasculitis is made clinically, and confirmed with the help of fundus fluorescein angiography. Active vascular disease is characterized by exudates around retinal vessels resulting in white sheathing or cuffing of the affected vessels. In this review, a practical approach to the diagnosis of retinal vasculitis is discussed based on ophthalmoscopic and fundus fluorescein angiographic findings.

Acute retinal arterial occlusive disorders

The initial section deals with basic sciences; among the various topics briefly discussed are the anatomical features of ophthalmic, central retinal and cilioretinal arteries which may play a role in acute retinal arterial ischemic disorders. Crucial information required in the management of central retinal artery occlusion (CRAO) is the length of time the retina can survive following that. An experimental study shows that CRAO for 97min produces no detectable permanent retinal damage but there is a progressive ischemic damage thereafter, and by 4h the retina has suffered irreversible damage. In the clinical section, I discuss at length various controversies on acute retinal arterial ischemic disorders. Classification of acute retinal arterial ischemic disorders: These are of 4 types: CRAO, branch retinal artery occlusion (BRAO), cotton wool spots and amaurosis fugax. Both CRAO and BRAO further comprise multiple clinical entities. Contrary to the universal belief, pathogenetically, clinically and for management, CRAO is not one clinical entity but 4 distinct clinical entities - non-arteritic CRAO, non-arteritic CRAO with cilioretinal artery sparing, arteritic CRAO associated with giant cell arteritis (GCA) and transient non-arteritic CRAO. Similarly, BRAO comprises permanent BRAO, transient BRAO and cilioretinal artery occlusion (CLRAO), and the latter further consists of 3 distinct clinical entities - non-arteritic CLRAO alone, non-arteritic CLRAO associated with central retinal vein occlusion and arteritic CLRAO associated with GCA. Understanding these classifications is essential to comprehend fully various aspects of these disorders. Central retinal artery occlusion: The pathogeneses, clinical features and management of the various types of CRAO are discussed in detail. Contrary to the prevalent belief, spontaneous improvement in both visual acuity and visual fields does occur, mainly during the first 7 days. The incidence of spontaneous visual acuity improvement during the first 7 days differs significantly (p<0.001) among the 4 types of CRAO; among them, in eyes with initial visual acuity of counting finger or worse, visual acuity improved, remained stable or deteriorated in non-arteritic CRAO in 22%, 66% and 12% respectively; in non-arteritic CRAO with cilioretinal artery sparing in 67%, 33% and none respectively; and in transient non-arteritic CRAO in 82%, 18% and none respectively. Arteritic CRAO shows no change. Recent studies have shown that administration of local intra-arterial thrombolytic agent not only has no beneficial effect but also can be harmful. Prevalent multiple misconceptions on CRAO are discussed. Branch retinal artery occlusion: Pathogeneses, clinical features and management of various types of BRAO are discussed at length. The natural history of visual acuity outcome shows a final visual acuity of 20/40 or better in 89% of permanent BRAO cases, 100% of transient BRAO and 100% of non-arteritic CLRAO alone. Cotton wools spots: These are common, non-specific acute focal retinal ischemic lesions, seen in many retinopathies. Their pathogenesis and clinical features are discussed in detail. Amaurosis fugax: Its pathogenesis, clinical features and management are described.

Retinal Vasculitis

Retinal vasculitis is a sight-threatening intraocular inflammation affecting the retinal vessels. It may occur as an isolated ocular condition, as a manifestation of infectious or neoplastic disorders, or in association with a systemic inflammatory disease. The search for an underlying etiology should be approached in a multidisciplinary fashion based on a thorough history, review of systems, physical examination, and laboratory evaluation. Discrimination between infectious and noninfectious etiologies of retinal vasculitis is important because their treatment is different. This review is based on recently published articles on retinal vasculitis and deals with its clinical diagnosis, its link with systemic diseases, and its laboratory investigation.

Central and Paracentral Visual Field Defects and Driving Abilities

The effect of central and paracentral visual field defects on driving abilities has until now received little attention. To date studies and surveys have concentrated on visual acuity and peripheral field loss. Here we summarise for the first time those diseases causing central visual field defects likely to be associated with binocular visual acuity adequate for driving.

Sudden painless unilateral vision loss caused by branch retinal artery occlusion: implications for the primary care physician

We report a case of sudden onset visual loss caused by branch retinal artery occlusion. Systematic search for the cause of branch retinal artery occlusion revealed Factor V Leiden mutation and antiphospholipid antibody syndrome as the cause. Implications for diagnosis and management are discussed.

Retinal arterial wall plaques in Susac syndrome

PURPOSE

To demonstrate retinal arterial wall plaques (RAWPs) in patients with Susac syndrome, a disorder that consists of the triad of branch retinal artery occlusion, encephalopathy, and hearing loss. The clinician may misinterpret these RAWPs as emboli.

DESIGN

Observational case series.

METHODS

Four patients (one man and three women, aged 21-38 years) were examined and followed.

RESULTS

Four patients with Susac syndrome had RAWPs in association with branch retinal artery occlusions. They were present in six of eight eyes. The plaques were yellow to yellow-white and located usually away from retinal bifurcations. Retinal arterial wall plaques occur at the midarteriolar segments, whereas Hollenhorst plaques occur at vascular bifurcations. Four of six eyes had resolution of the plaques.

CONCLUSIONS

Retinal arterial wall plaques may occur with branch retinal artery occlusions in Susac syndrome. This finding should help the clinician who is struggling to make a diagnosis in a patient with an enigmatic encephalopathy and/or hearing loss. These plaques may resolve over time.

Anticardiolipin antibodies and occlusive vascular disease of the eye: prospective study

There is a recognized association between the presence of anticardiolipin antibodies and vascular occlusive disease. The purpose of our study is to detect the presence of high titers of anticardiolipin antibodies (ACA) in the serum and to correlate the titers with the severity of the vascular disease in patients with occlusive ocular vascular disease. 82 patients were included in a prospective study; 25 patients with anterior ischaemic optic neuropathy, 36 with retinal vein occlusion and 21 with retinal artery occlusion. ACA (IgG and IgM isotypes) were measured by ELISA in the sera of all patients. The group of the patients (group A) was compared to an age-matched control group of 79 healthy individuals (group B). IgG isotype (but not IgM) titers of ACA were found significantly higher in group A (P < 0.001). In patients with titers of ACA (IgG isotype) > 100 units we noted a higher incidence of a more severe disease (recurrency, involvement of both eyes or extraocular manifestations) especially among those with anterior ischaemic optic neuropathy and secondarily in those with retinal artery occlusion. Our results suggest that the association between high titers of ACA and occlusive vascular disease of the eye concerns only the IgG isotype. In addition, the detection of high titers of IgG/AGA in patients could be a useful marker for disease severity and prognosis and this observation seems to be more explicit in cases with arterial occlusive disease than in cases with venous occlusive disease.

Microemboli are not a prerequisite in retinal artery occlusive diseases

PURPOSE

Retinal artery occlusion (RAO) is caused by arterio-arterial or cardiovascular emboli in about 50% of all cases, but the role of non-embolic causes remains unclear.

SUBJECTS AND METHODS

We studied 27 patients with amaurosis fugax (AFX), branch retinal artery occlusion (BRAO), central retinal artery occlusion (CRAO) and anterior ischaemic optic neuropathy (AION). Patients underwent an evaluation of cerebrovascular and cardiovascular risk factors, measurement of haemorheological parameters, and Doppler/duplex sonography including ultrasound detection of cerebral microembolic signals and echocardiography.

RESULTS

Forty-one per cent of the patients had internal carotid atherosclerosis but only one patient had microembolic signals, probably due to a cardiac thrombus. Vascular risk factors, especially hypertension, were present in 82% of the patients correlating with abnormal haemorheological parameters such as increased thrombocyte reactivity.

CONCLUSIONS

Our results indicate that altered haemorheological parameters, especially increased thrombocyte reactivity and vascular risk factors such as arterial hypertension, are non-embolic causes of vascular disease in a significant number of patients with RAO. This should guide diagnostic and therapeutic considerations concerning RAO in cases without proven embolic sources.

Urticaria in idiopathic bilateral recurrent branch retinal arterial occlusion

Idiopathic bilateral recurrent branch retinal arterial occlusion (IBRBRAO) is a rare syndrome characterized by migraine headaches, tinnitus, vertigo, hearing loss, and recurrent branch retinal artery occlusion of unknown etiology. Affected patients frequently undergo a wide range of medical evaluation and have no apparent pathologic findings. We present here a case of IBRBRAO, associated with urticarial rash, not described in this syndrome in previous publications.

Reversal of visual loss with hyperbaric oxygen treatment in a patient with Susac syndrome

PURPOSE

The purpose of the study is to report on a 34-year-old woman with Susac syndrome who presented on two separate occasions with visual acuity loss from a recurrent branch retinal artery occlusion and underwent hyperbaric oxygen treatment with favorable outcome.

METHODS

Visual acuity was 20/400 in the left eye and count fingers in the right eye after separate occlusive events. The patient underwent hyperbaric oxygen treatment on each occasion of visual acuity loss. The patient subsequently was diagnosed with Susac syndrome (microangiopathy of the retina, brain, and middle ear). The authors present visual fields, photographs, angiograms, and ancillary tests documenting diagnosis and course of treatment.

RESULTS

On each occasion, visual acuity improved to 20/25 during and was maintained after hyperbaric oxygen treatment. Visual fields showed improvement immediately after treatment.

CONCLUSION

This is the first report of hyperbaric oxygen treatment for Susac syndrome. Dramatic post-treatment visual field and acuity changes suggest benefit of treatment. Hyperbaric oxygen treatment can be considered a treatment option for visual complications of this syndrome. Susac syndrome should be included in the differential diagnosis of recurrent branch retinal artery occlusion.

Branch retinal artery occlusion in a child

BACKGROUND

Retinal artery occlusive events are unusual in the paediatric population. The average age of their occurrence is 60 years and the aetiology most often related to cardiovascular disease.

CASE REPORT

A healthy 11-year-old white girl developed permanent unilateral visual field loss as a result of a branch retinal artery occlusion. An extensive work-up included transthoracic and transoesophageal echocardiograms, routine haematological and biochemical testing including serum lipids, screening for thrombophilia and thrombolysis, as well as autoantibodies, all of which proved to be within normal limits.

CONCLUSIONS

Recognition of the underlying aetiology is not always possible, but should be sought as prognosis for vision or survival may rest upon these findings.