Treatment of Susac's syndrome

Phenotyping vestibulocochlear manifestations in Susac syndrome: a cohort study

PURPOSE

To characterize vestibulocochlear involvement in patients with Susac syndrome (SuS), a rare immune-mediated endotheliopathy of cerebral, retinal and inner ear microvasculature causing a triad of encephalopathy, branch retinal artery occlusions and sensorineural hearing loss.

METHODS

The electronic patient files of 21 patients with SuS are reviewed for data on demography, clinical presentation, disease course and audiovestibular testing.

RESULTS

All 21 patients experienced some form of audiovestibular complaints during the disease course, with vertigo and instability being most frequently reported, followed by hearing loss, tinnitus and aural fullness. These audiovestibular symptoms did not always coincide. Fifteen patients had objectified predominant low- to midfrequency sensorineural hearing loss and 8 out of 18 patients showed abnormalities on vestibular testing, most frequently vestibular evoked myogenic potential-abnormalities, indicating otolith dysfunction. Treatment protocols consisted of uniformly extensive immunosuppressive therapy and hearing loss remained mostly mild.

CONCLUSION

Audiovestibular involvement is very common in patients with SuS. Characteristic findings include a "reverse-slope" configuration on audiological testing and otolith dysfunction on vestibular testing. Aggressive immunosuppression may prevent severe audiovestibular dysfunction. Symptoms as aural fullness and otolith dysfunction may indicate an underlying hydrops. Further investigations are necessary to elucidate the histopathological mechanisms underlying these preferentially involved cochleovestibular areas. Early recognition and treatment of SuS are important to stabilize or decrease disease activity and might also have beneficial effects on inner ear outcome. THE SUBMITTED MANUSCRIPT REPORTS DATA DERIVED FROM CLINICAL OBSERVATIONS IN HUMANS: Consent for the research was provided by the Ethics Committee of Ghent University hospital (application number 2019/1443, registration date 31/12/2021, principal investigator Guy Laureys).

Long-term cognitive outcomes in Susac syndrome: A case series

Susac syndrome (SuS) presents with encephalopathy, visual disturbances, and hearing loss from immune-mediated microvascular occlusion. While acute SuS is well-described, long-term cognitive outcomes with current treatments are underknown. We assessed ten SuS patients treated in accordance with evidence-based guidelines using immunotherapies targeting humoral and cell-mediated pathways. Patients were followed for a median 3.6 years. Initially, cognition inversely correlated with corpus callosum lesions on MRI. All reported cognitive improvement; 5/10 patients had residual deficits in visual attention and executive function. Early, aggressive treatment was associated with good outcomes; extensive early corpus callosum lesions may identify patients at-risk of persistent cognitive deficits.

Fluorescein Angiography Findings in Susac Syndrome: A Multicenter Retrospective Case Series

BACKGROUND

Susac syndrome is a vasculopathy, resulting in the classic triad of branch retinal artery occlusion (BRAO), inner ear ischemia, and brain ischemia. In this retrospective chart review, we characterize fluorescein angiography (FA) findings and other ancillary studies in Susac syndrome, including the appearance of persistent disease activity and the occurrence of new subclinical disease on FA.

METHODS

This multicenter, retrospective case series was institutional review board-approved and included patients with the complete triad of Susac syndrome evaluated with FA, contrasted MRI of the brain, and audiometry from 2010 to 2020. The medical records were reviewed for these ancillary tests, along with demographics, symptoms, visual acuity, visual field defects, and findings on fundoscopy. Clinical relapse was defined as any objective evidence of disease activity during the follow-up period after initial induction of clinical quiescence. The main outcome measure was the sensitivity of ancillary testing, including FA, MRI, and audiometry, to detect relapse.

RESULTS

Twenty of the 31 (64%) patients had the complete triad of brain, retinal, and vestibulocochlear involvement from Susac syndrome and were included. Median age at diagnosis was 43.5 years (range 21-63), and 14 (70%) were women. Hearing loss occurred in 20 (100%), encephalopathy in 13 (65%), vertigo in 15 (75%), and headaches in 19 (95%) throughout the course of follow-up. Median visual acuity at both onset and final visit was 20/20 in both eyes. Seventeen (85%) had BRAO at baseline, and 10 (50%) experienced subsequent BRAO during follow-up. FA revealed nonspecific leakage from previous arteriolar damage in 20 (100%), including in patients who were otherwise in remission. Of the 11 episodes of disease activity in which all testing modalities were performed, visual field testing/fundoscopy was abnormal in 4 (36.4%), MRI brain in 2 (18.2%), audiogram in 8 (72.7%), and FA in 9 (81.8%).

CONCLUSIONS

New leakage on FA is the most sensitive marker of active disease. Persistent leakage represents previous damage, whereas new areas of leakage suggest ongoing disease activity that requires consideration of modifying immunosuppressive therapy.

Behavioral Impairment and Amnesia at the Onset of Susac Syndrome

Susac syndrome (SS) is an autoimmune microangiopathy that affects the brain, retina, and inner ear, causing a wide range of clinical manifestations. The triad of encephalopathy, visual disturbances, and hearing loss constitute the classic disease presentation. We describe an original clinical case of a young male with a definitive diagnosis of SS, who presented with disordered behavior and amnesia, initially manifested as a dissociative or anxiety disorder but with a fulminant evolution toward severe encephalopathy associated with retinal infarcts and sensorineural hearing loss. After the diagnosis of SS, aggressive immunosuppressive treatment was started with significant neurological improvement and favorable evolution during the follow-up period. SS is a rare but potentially devastating disease that can cause great disability if not properly diagnosed and treated. The onset of SS with behavioral or psychiatric manifestation can be misleading, causing a diagnostic delay.

Susac Syndrome: Description of a Single-Centre Case Series

This study describes the clinical characteristics, diagnostic results, treatment regimens, and clinical course of a cohort of patients with Susac syndrome (SS). It is a retrospective observational study of all patients with the diagnosis of SS evaluated at the Hospital Clinic (Barcelona, Spain) between March 2006 and November 2020. Nine patients were diagnosed with SS. The median time from the onset of the symptoms to diagnosis was five months (IQR 9.0), and the median follow-up time was 44 months (IQR 63.5). There was no clear predominance of sex, and mean age of symptoms onset was 36 years (range 19–59). Six patients (67%) presented with incomplete classical clinical triad, but this eventually developed in six patients during the disease course. Encephalopathy, focal neurological signs, visual disturbances, and hearing loss were the most frequent manifestations. Brain magnetic resonance imaging showed callosal lesions in all patients. Most were in remission within two years. Only four patients met the proposed criteria for definite SS. When SS is suspected, a detailed diagnostic workup should be performed and repeated over time to identify the clinical manifestations that will lead to a definite diagnosis.

EVALUATION OF TUMOR NECROSIS FACTOR INHIBITOR THERAPY IN SUSAC SYNDROME

PURPOSE

To evaluate the effect of tumor necrosis factor (TNF) inhibitor therapy on ocular relapses in patients with Susac syndrome.

METHODS

Multicenter retrospective cohort study of patients diagnosed with Susac syndrome according to classical clinical criteria. We evaluated the disease activity before and after introduction of anti-TNF therapy and its value as a steroid-sparing agent.

RESULTS

Five patients were included. All were initially treated with a combination of corticosteroids and classical immunosuppressive drugs. Infliximab was started in three patients, and adalimumab was started in two patients. Patients had on average 5 ocular relapses during a mean follow-up time of 2.59 years before introducing a TNF inhibitor, corresponding with on average 1.93 relapses per year. After the introduction of an anti-TNF agent, this number was reduced by factor 5.51 to an average of 0.35 relapses per year for a mean follow-up of 2.86 years (P = 0.10). Before anti-TNF introduction ocular relapses occurred at a mean daily dose of 34 mg of prednisone, whereas with anti-TNF treatment, corticosteroid administration could be completely stopped in four patients with one patient still needing 5 mg daily (P = 0.10). Infliximab and adalimumab generally were well tolerated, and no serious adverse events were reported.

CONCLUSION

Although not statistically significant, our results suggest that anti-TNF therapy can be a valuable option for the treatment of ocular Susac syndrome and may especially be considered in those patients unresponsive to more conventional immunosuppressive treatment.

Headache in Susac's Syndrome

PURPOSE OF REVIEW

Provide an overview of the current diagnosis, pathophysiology, and treatment of Susac's syndrome (SuS), with special emphasis on summarizing what is currently known about headache as a symptom of disease activity.

RECENT FINDINGS

The most recent literature in SuS has focused on furthering the understanding of the underlying pathology and efficacy of treatments for SuS. The importance of early recognition to facilitate timely treatment and avoid long-term disability has been highlighted. Headache, the most common symptom experienced by patients with SuS, can occur up to 6 months in advance of other symptoms, and exacerbations of headache can herald increased disease activity. Susac's syndrome (SuS) is a rare disorder classically characterized by triad of encephalopathy, branch retinal artery occlusion (BRAO), and sensory neuronal hearing loss (SNHL). The full triad is uncommon at initial presentation, which can confound efforts to make timely diagnosis and treatment decisions. Headache is the most common symptom in SuS, is often an early feature, and can help separate SuS from other diagnoses in the differential. However, the features and management of the headache associated with SuS have not been systematically defined in the literature.

Susac syndrome (Retino-cochleo-cerebral vasculitis), the ophthalmologist in the role of the whistleblower

BACKGROUND/PURPOSE

Susac syndrome is a rare microangiopathy of suspected autoimmune origin affecting arteries of the retina, the cochlea and the brain. The aim of the study was to give a review of the disease entity and determine the proportion of cases and their characteristics in a uveitis referral centre.

PATIENTS AND METHODS

Charts of patients with the diagnosis of Susac syndrome seen in the Uveitis Clinic of the Centre for Ophthalmic Specialised Care (COS), Lausanne, Switzerland were reviewed retrospectively to determine the frequency of such cases in a uveitis referral centre. Clinical symptoms and signs, functional data, imaging signs and evolution were analysed in the 3 COS cases and one case shared with the Uveitis Clinic of the Department of Ophthalmology, University of Innsbruck, Austria. Characteristic signs were searched possibly allowing a prompt diagnosis.

RESULTS

During the period from 1994 to 2019 (24 years, 2045 patients), 3 charts with the diagnosis of Susac syndrome were found (0.15%). The whole collective, including the additional case, comprised three women aged 28, 32 and 63 at presentation and one man, aged 42. None of the 3 cases that were referred were diagnosed beforehand. The characteristic item found in all 4 cases was the abrupt arterial stop or segmental interruption of arteries and increased staining of arterial wall on angiography more clearly shown on indocyanine green angiography that can potentially be proposed as a crucial diagnostic element. All 4 cases responded to dual steroidal and non-steroidal immunosuppression. Under treatment, all four patients did not show any further evolution.

CONCLUSION

Susac syndrome is a multilocation arteritis of the head that can involve the eye, ear and brain often first diagnosed by the ophthalmologist. The diagnosis is rapidly reached in uveitis referral centres but seems to be missed otherwise, A helpful angiographic sign to be searched is an abrupt or segmental arterial stop and increased staining of the arterial wall more clearly seen on indocyanine green angiography. Patients often present first to the ophthalmologist who should be acting as a whistleblower to avoid severe involvement of the brain.

The Successful Use of Infliximab in a Relapsing Case of Susac's Syndrome

Susac's syndrome is a rare and debilitating disease characterized by the triad of encephalopathy, branch retinal artery occlusions, and sensorineural hearing loss. All manifestations may not be clinically apparent at presentation resulting in delayed diagnosis. Early recognition of the syndrome may prevent disease sequelae such as permanent cognitive, visual, and hearing loss. We present such a case of Susac's syndrome that was also refractory to conventionally prescribed combination of immunosuppressive treatments including high-dose potent corticosteroids, intravenous cyclophosphamide, methotrexate, plasma exchange, rituximab, and mycophenolate. His disease was stabilized with infliximab in combination with a tapering course of low-dose prednisone. After 2 years of remission with TNF treatment, consideration is being given to ceasing therapy. He has the sequelae of bilateral sensorineural hearing loss but no visual impairment or cognitive deficits on follow-up with neuropsychometric testing. This is the first case report to our knowledge of the successful use of infliximab for a patient with Susac's syndrome that was necessary following treatment with cyclophosphamide and then rituximab.

Progressive sensorineural hearing loss many years preceding completion of Susac's syndrome triad: A case report

Susac's syndrome (SuS) is a rare disorder with a clinical triad of encephalopathy, sensorineural hearing loss, and branch retinal artery occlusions. We report a 7-year-old girl who presented with chronic, progressive sensorineural hearing loss, who, years later, presented with encephalopathy and vision loss. Such prolonged period between symptoms is unusual and to our knowledge, this is the longest interval between onset of hearing loss and completion of the full triad in SuS. In addition, she had a protracted disease course, requiring multiple immune therapies for disease control.

Otologic manifestations of Susac syndrome

Susac syndrome, a rare autoimmune disorder first described as a classic triad (encephalopathy, branch retinal artery occlusion, and sensorineural hearing loss) in 1979 by renowned physician John O. Susac, has been an advancing area of clinical interest and scientific research over the last several decades. This comprehensive review aims to succinctly highlight the breadth and detail of this enigmatic disease, with a primary focus on otologic manifestations. Topics discussed include epidemiology, pathophysiology, clinical manifestations, differential diagnoses, classification schema, laboratory investigations, characteristic audiometric findings, high-yield radiographic imaging, temporal bone histopathology, treatment strategies and overall prognosis.

Guidelines for treatment of Susac syndrome - An update

Susac syndrome is an immune-mediated, pauci-inflammatory, ischemia-producing, occlusive microvascular endotheliopathy/basement membranopathy that affects the brain, retina, and inner ear. Treatment of Susac syndrome is particularly challenging. The organs involved can easily become irreversibly damaged, and the window of opportunity to protect them is often short. Optimal outcome requires rapid and complete disease suppression. Adding to the challenge is the absence of objective biomarkers of disease activity and the great variability in presentation, timing and extent of peak severity, duration of peak severity, and natural disease course. There have been no randomized controlled trials or prospective treatment studies. We offer treatment guidelines based on cumulative clinical experience and a large cohort of patients followed longitudinally in a comprehensive database project. These guidelines state our preferences but do allow flexibility and discuss other options. The guidelines also serve as an initial step in the planning of prospective treatment studies, future consensus-based recommendations, and future randomized controlled trials.

Susac syndrome: clinical characteristics, clinical classification, and long-term prognosis

Susac syndrome is a rare condition characterized by the clinical triad of central nervous system (CNS) dysfunction, sensorineural hearing impairment, and branch retinal artery occlusion (BRAO). The purpose of this study is to examine the demographics, clinical characteristics, treatment, and long-term prognosis of Susac syndrome. The data recorded for all Susac syndrome patients treated at the Sheba Medical Center between 1998 and 2014 included demographics, clinical signs at presentation and during the disease course, imaging findings, treatment, and prognosis.Susac syndrome was diagnosed in 10 patients (age range 30-45 years). Only 2 patients presented with the full triad and 7 patients developed the full triad during mean follow-up period of 35 months. The average time to full triad was 7 months. Based on our observations at presentation, we divided the disease course into suspected, incomplete, and complete Susac syndrome. All 10 patients were treated at diagnosis with a pulse of high-dose intravenous methylprednisolone. There was improvement in visual acuity and visual field at the end of follow-up compared to baseline, but it was not statistically significant (P = 0.479 and P = 0.053, respectively). Five patients remained with neurological damage, and 5 patients had no improvement of their hearing loss at study closure. In conclusion, Susac syndrome is a rare condition that can mimic other disorders. The diagnosis is challenging because most patients do not initially present with the definitive triad. We suggest a clinical classification for the syndrome that may assist in early diagnosis.

Neurocognitive Profile of a Woman with Susac's Syndrome: Further Evidence of Cognitive Variability

OBJECTIVE

Susac's syndrome is a rare autoimmune disease characterized by encephalopathy, retinal artery occlusions, hearing loss, and lesions to the corpus callosum. To date, only four papers (five cases) have described the neuropsychological effects of the syndrome. Extant case reports of Susac's syndrome have documented varying levels of cognitive impairment; some studies have identified diffuse cerebral dysfunction, while others describe more focal impairments in attention, memory, and executive functioning.

METHOD

The goal of this case study was to provide comprehensive neurocognitive data obtained from another case of confirmed Susac's syndrome. As such, we present the case of a 42-year-old woman with a two-year history of Susac's syndrome. At the time of the neuropsychological evaluation, the patient described ongoing difficulties with memory, word-finding problems, problems with math, and poor problem-solving. Physical/sensory changes included hearing loss, tinnitus, and migraines.

RESULTS

Neuropsychological test results revealed the patient to be a woman of estimated average to high average premorbid intellect who exhibited a number of focal inefficiencies in the context of a generally intact profile. Particular cognitive weaknesses emerged on select tasks involving visuoconstruction, encoding of a wordlist, and bilateral speeded finger oscillations. She also committed three failures to maintain set on a task of cognitive flexibility. There was no evidence of memory deficits.

CONCLUSIONS

Our findings provide further evidence of cognitive interindividual variability in a confirmed case of Susac's syndrome.

SUSAC SYNDROME

PURPOSE

To describe an atypical presentation of Susac syndrome.

METHODS

Observational case report.

RESULTS

A 44-year-old man with no significant medical history presented with inferonasal visual field loss in his left eye of several months of duration. He was found to have bilateral migratory arteritis with focal areas of arteriolar occlusion in both eyes and peripheral ischemia superotemporally in his left eye. An extensive hematologic workup was negative for autoimmune disease or coagulopathy. Magnetic resonance imaging with contrast of his brain revealed a hyperintense lesion in the splenium of the corpus callosum. Auditory testing was significant for nonspecific high-frequency hearing loss in the right ear. Given the full clinical picture, a diagnosis of Susac syndrome was made.

CONCLUSION

Susac syndrome is a multisystemic, immune-mediated occlusive endotheliopathy characterized by the clinical triad of encephalopathy, branch retinal artery occlusions, and hearing loss. However, patients may present with varying degrees of this triad; thus, there should be a high index of suspicion in patients presenting with multiple artery occlusions or multifocal arteritis.

Susac's syndrome during pregnancy - the first Croatian case

Susac's syndrome (SS) is an infrequent neurological disorder characterized by the clinical triad of encephalopathy, branch retinal artery occlusion and hearing loss due to an autoimmune endotheliopathy associated with anti-endothelial cell antibodies. At the onset of the disease SS rarely appears with the complete clinical triad. The most important diagnostic procedures involved in the diagnosis of SS are brain MRI, audiometric testing and retinal fluorescein angiography. Presence of at least two components of the SS clinical triad accompanied by specific brain MRI findings is highly suggestive of SS. We report a case of a young pregnant woman with a history of encephalopathy, hearing loss and walking impairment. Brain MRI revealed a spectrum of findings previously described in patients with SS. We induced labor at 37 weeks' gestation to start with immunosuppressive treatment and avoid possible fetal toxicity. To the best of our knowledge this is the first report of SS in Croatia.

Susac's syndrome--pathogenesis, clinical variants and treatment approaches

Susac's syndrome is a rare disease that is characterised by the clinical triad of encephalopathy, branch retinal artery occlusion, and sensorineural hearing loss. It was first described as a distinctive syndrome by Susac in 1979. There have been 304 reported individual patients with Susac's syndrome. Etiopathogenesis is not clear, although it is now thought that it is an immune-mediated endotheliopathy that affects the microvasculature of the brain, retina, and inner ear. Antiendothelial cell antibodies (AECAs) play an important role in mediating the endothelial cell injury with consequent deposition of thrombotic material in the lumen of the small vessel. In biopsies of the brain, microinfarcts with atrophy of the white and grey matter could be detected. These microinfarcts are caused by a microangiopathic process with arteriolar wall proliferation, lymphocytic infiltration and basal lamina thickening. At clinical onset, the most common manifestation was central nervous system symptoms, followed by visual symptoms and hearing disturbances. Diagnosis is based on Magnetic Resonance Imaging (MRI), retinal fluorescein angiography, and audiometry; these are considered crucial tests to enable diagnosis. Antiendothelial cell antibodies (AECAs) are also of diagnostic relevance. Based on the hypothesis of being an autoimmune disease, treatment has to be immunosuppressive. In addition, anticoagulation measures, antiplatelet agents and antivasospastic agents should be considered. The majority of patients did not initially present with the complete triad of symptoms. An appropriate approach would be to perform a search for absent components of the triad if the clinical presentation is suggestive of Susac's syndrome. Improved understanding of the presentation of Susac's syndrome will prevent misdiagnosis and ensure that patients receive the best possible care.

Clinical, paraclinical and serological findings in Susac syndrome: an international multicenter study

Background

Susac syndrome (SuS) is a rare disorder thought to be caused by autoimmune-mediated occlusions of microvessels in the brain, retina and inner ear leading to central nervous system (CNS) dysfunction, visual disturbances due to branch retinal artery occlusions (BRAO), and hearing deficits. Recently, a role for anti-endothelial cell antibodies (AECA) in SuS has been proposed.

Objectives

To report the clinical and paraclinical findings in the largest single series of patients so far and to investigate the frequency, titers, and clinical relevance of AECA in SuS.

Patients and methods

A total of 107 serum samples from 20 patients with definite SuS, 5 with abortive forms of SuS (all with BRAO), and 70 controls were tested for AECA by immunohistochemistry employing primate brain tissue sections.

Results

IgG-AECA >1:100 were detected in 25% (5/20) of patients with definite SuS and in 4.3% (3/70) of the controls. Median titers were significantly higher in SuS (1:3200, range 1:100 to 1:17500) than in controls (1:100, range 1:10 to 1:320); IgG-AECA titers >1:320 were exclusively present in patients with SuS; three controls had very low titers (1:10). Follow-up samples (n = 4) from a seropositive SuS patient obtained over a period of 29 months remained positive at high titers. In all seropositive cases, AECA belonged to the complement-activating IgG1 subclass. All but one of the IgG-AECA-positive samples were positive also for IgA-AECA and 45% for IgM-AECA. SuS took a severe and relapsing course in most patients and was associated with bilateral visual and hearing impairment, a broad panel of neurological and neuropsychological symptoms, and brain atrophy in the majority of cases. Seropositive and seronegative patients did not differ with regard to any of the clinical or paraclinical parameters analyzed.

Conclusions

SuS took a severe and protracted course in the present cohort, resulting in significant impairment. Our finding of high-titer IgG1 and IgM AECA in some patients suggest that humoral autoimmunity targeting the microvasculature may play a role in the pathogenesis of SuS, at least in a subset of patients. Further studies are warranted to define the exact target structures of AECA in SuS.

Central retinal artery occlusion and Susac syndrome: a case report

BACKGROUND

Susac syndrome is a rare disease attributed to microangiopathy involving the arterioles of the brain, retina, and cochlea. Understanding the pathogenesis is incomplete, but an immune-mediated process remains the leading hypothesis.

METHODS

Report of a single case of a previously healthy 22-year-old female patient showing the complete clinical triad.

RESULTS

Diagnosis of Susac syndrome in this patient was first questioned due to the atypical initial ophthalmologic presentation with central retinal artery occlusion. Multiple relapses occurred in the fellow eye during follow-up, showing the typical branch retinal artery occlusions, allowing definite diagnosis.

CONCLUSION

Susac syndrome should be considered in the differential diagnosis when facing (young) patients with central retinal artery occlusion, especially in the presence of unexplained encephalopathy and/or sensorineural hearing loss.

A case of Susac syndrome with cervical spinal cord involvement on MRI

We describe a typical case presentation of Susac syndrome with a novel MRI finding of cervical spinal cord involvement. A 25-year-old, 14-week gestation white woman presented with two episodes of encephalopathy, responsive to steroids, with abnormal brain magnetic resonance imaging (MRI) concerning for Susac syndrome. Further studies confirmed the clinical triad of encephalopathy, branch retinal artery occlusions and hearing loss pathognomonic for Susac syndrome. Cervical spine MRI demonstrated two focal areas of high-signal abnormality at C2 and C3. We provide a brief review of Susac syndrome, data regarding pregnancy in this rare syndrome, and discuss how this unique observation may assist in the medical management of such cases and contribute to the understanding of the underlying pathophysiology.

Encephalopathic Susac's Syndrome associated with livedo racemosa in a young woman before the completion of family planning

Background

Susac’s Syndrome (SS) consists of the triad of encephalopathy, branch retinal artery occlusions (BRAO) and hearing loss (HL). Histopathologically, SS is characterised by a microangiopathy, and some observations suggest that an immune-mediated damage of endothelial cells might play a role. These findings also implicate a similarity between SS and other autoimmune diseases, most notably juvenile dermatomyositis (JDM). However, SS and JDM are commonly thought to affect distinct and non-overlapping sets of organs, and it is currently not clear how these specificities arise. Moreover, in the absence of clinical trials, some authors suggest that therapeutic approaches in SS should rely on the model of other autoimmune diseases such as JDM.

Case presentation

Here, we report a case of SS in a 32-year-old pregnant woman. She initially was admitted to the hospital with subacute severe encephalopathy and multifocal neurologic signs. As cranial magnetic resonance imaging (MRI) revealed multifocal white matter lesions including the corpus callosum, erroneously a diagnosis of multiple sclerosis (MS) was made, and intravenous methylprednisolone (IVMP) therapy was initiated. A few days later, an exanthema appeared on the trunk and extremities, which was diagnosed as livedo racemosa (LR). Several weeks later, the patient was readmitted to the clinic with an obscuration of her left visual hemifield and a bilateral HL. Ophthalmologic examination revealed extensive ischemic damage to both retinae. Now the correct diagnosis of SS was established, based on the above triad of clinical symptoms in conjunction with typical MRI and fundoscopic findings. When SS was diagnosed, the standard therapy with intravenous cyclophosphamide (IVCTX) was not instituted because of a significant risk of permanent infertility. Instead, sustained control of disease activity could be achieved with a therapeutic regime combining prednisolone, intravenous immunoglobulins (IVIG), mycophenylate mofetil (MM), and methotrexate (MTX).

Conclusions

An association with LR has only been described in very few cases of SS before and further underlines the pathogenetic relationship between SS and other autoimmune diseases such as JDM. In young women with SS and the desire for a child the combination of MM and MTX may represent a reasonable alternative to IVCTX.

Susac's syndrome as HIV-associated immune reconstitution inflammatory syndrome

Susac’s Syndrome (SS) is an autoimmune endotheliopathy of cerebral, retinal and cochlear arterioles. We report of an HIV-infected woman who developed a first SS episode following a spontaneous reduction of plasma viral load and several relapses six years later, following initiation of combined antiretroviral therapy (cART). Corticosteroids and intravenous immunoglobulins alone did not control the disease, which improved after combined treatment with acyclovir and ganciclovir. SS onset in HIV infection and relapses during cART-induced immune reconstitution are consistent with the dysimmune nature of the disease. The response to anti-herpes drugs suggests a viral contribute in this case of SS.

Susac's Syndrome in a 27-Year-Old Female

A 27-year-old woman was referred by the neurologist for ophthalmic examination. She had a history of headache, visual loss in her right eye, four-limb paresthesia, and behavioral changes over the previous 10 months. The patient complained of tinnitus and hearing loss for two weeks. The patient was initially diagnosed with multiple sclerosis, but auditory and retinal involvement (small branch retinal artery occlusion in fluorescein angiography) raised the possibility of Susac's syndrome.

Lesion morphology at 7 Tesla MRI differentiates Susac syndrome from multiple sclerosis

Background:

Although an orphan disease with still obscure aetiopathogenesis, Susac syndrome has to be considered as differential diagnosis in multiple sclerosis (MS), since its clinical presentation and paraclinical features including routine magnetic resonance imaging (MRI) findings partially overlap.

Objective:

We aimed to study a potential benefit of 7T MRI for (i) the differentiation between Susac syndrome and MS and (ii) the clarification of pathogenesis of Susac syndrome.

Methods:

Five patients suffering from Susac syndrome, 10 sex- and age-matched patients with relapsing–remitting MS (median Expanded Disability Status Scale (EDSS) score 1.5) and 15 matching healthy controls were investigated at 7 Tesla MRI. The protocol included T1-weighted MPRAGE, T2*-weighted FLASH, and TIRM sequences.

Results:

Almost all T2* FLASH lesions in patients with MS were centred by a small central vein (325 lesions; 92%) and often showed a small hypointense rim (145 lesions; 41%). In contrast, white matter lesions in Susac syndrome exhibited a perivascular setting significantly less frequently (148 lesions; 54%, p=0.002), and very rarely exhibited a hypointense rim (12 lesions; 4%, p=0.004). Furthermore, in addition to callosal atrophy, Susac patients showed cerebrospinal fluid-isointense lesions within the central part of corpus callosum that are not commonly seen in MS.

Conclusion:

At 7T MRI, plaques in MS patients and patients with Susac syndrome differed substantially with respect to morphology and pattern. Thus, lesion morphology at 7T (i) may serve as a marker to distinguish Susac syndrome from MS and (ii) reflects a different pathophysiological mechanism underlying Susac syndrome, for example microinfarction rather than demyelination.

Patterns of retinal damage facilitate differential diagnosis between Susac syndrome and MS

Susac syndrome, a rare but probably underdiagnosed combination of encephalopathy, hearing loss, and visual deficits due to branch retinal artery occlusion of unknown aetiology has to be considered as differential diagnosis in various conditions. Particularly, differentiation from multiple sclerosis is often challenging since both clinical presentation and diagnostic findings may overlap. Optical coherence tomography is a powerful and easy to perform diagnostic tool to analyse the morphological integrity of retinal structures and is increasingly established to depict characteristic patterns of retinal pathology in multiple sclerosis. Against this background we hypothesised that differential patterns of retinal pathology facilitate a reliable differentiation between Susac syndrome and multiple sclerosis. In this multicenter cross-sectional observational study optical coherence tomography was performed in nine patients with a definite diagnosis of Susac syndrome. Data were compared with age-, sex-, and disease duration-matched relapsing remitting multiple sclerosis patients with and without a history of optic neuritis, and with healthy controls. Using generalised estimating equation models, Susac patients showed a significant reduction in either or both retinal nerve fibre layer thickness and total macular volume in comparison to both healthy controls and relapsing remitting multiple sclerosis patients. However, in contrast to the multiple sclerosis patients this reduction was not distributed over the entire scanning area but showed a distinct sectorial loss especially in the macular measurements. We therefore conclude that patients with Susac syndrome show distinct abnormalities in optical coherence tomography in comparison to multiple sclerosis patients. These findings recommend optical coherence tomography as a promising tool for differentiating Susac syndrome from MS.

A brief review of Susac syndrome

Susac syndrome was named after J.O. Susac who first described the syndrome in 1979. It is characterized by the clinical triad of encephalopathy, branch retinal artery occlusion, and sensorineural hearing loss. It mainly occurs in young women. This underdiagnosed disease needs to be considered in the differential diagnosis of a broad variety of disorders. In Susac syndrome, autoimmune processes leading to damage and inflammation-related occlusion of the microvessels in brain, retina, and inner ear are thought to play a causal role. The diagnosis is based primarily on the clinical presentation, the documentation of branch retinal artery occlusion by fluorescence angiography, and characteristic findings on cerebral MRI, that help in distinguishing Susac syndrome from other inflammatory entities, like multiple sclerosis. Antiendothelial cell antibodies could be detected in some patients. Patients are successfully treated with immunosuppression, however, the best regimen still needs to be defined. As a result of the rarity of the disease, controlled therapeutic trials are missing so far. In this review, we want to demonstrate the clinical features, natural history, treatment, and clinical course of Susac syndrome, illustrated by a typical case history.

Susac syndrome: clinical characteristics and treatment in 29 new cases

BACKGROUND AND PURPOSE

  There are few clinical studies on the attempted treatments and outcomes in patients with Susac syndrome (SS) (retinocochleocerebral vasculopathy).

METHODS

  A retrospective review was performed of all patients presenting with SS at the Mayo Clinic in Rochester, Minnesota, USA (1 January 1998-1 October 2011).

RESULTS

  There were 29 cases of SS (24 women, mean age at presentation, 35 years; range, 19-65; full triad of brain, eye, and ear involvement, n = 16; mean follow-up time, 29 months). Thirty CSF analyses were performed in 27 cases (mean protein 130 mg/dl, range 35-268; mean cell count 14, range 1-86). MRI of the brain showed corpus callosal involvement (79%), T2-weighted hyperintensities (93%), and gadolinium enhancement (50%). Average lowest modified Rankin Scale score was 2.5 (median 2, range 0-5). Most patients (93%) received immunosuppressive treatment, with a mean time to treatment of 2 months following symptomatic onset. Treatments included intravenous methylprednisolone or dexamethasone (n = 23), oral corticosteroids (n = 24), plasma exchange (PLEX) (n = 9), intravenous immunoglobulin (IVIg) (n = 15), cyclophosphamide (n = 6), mycophenolate mofetil (n = 5), azathioprine (n = 2), and rituximab (n = 1). Most patients also received an antiplatelet agent (n = 21). Improvement or stabilization was noted in eight of 11 cases treated with IVIg in the acute period (three experienced at least partial deterioration) and eight of nine cases of PLEX treatment (one lost to follow up).

CONCLUSIONS

  Susac syndrome may be severe, disabling, and protracted in some patients. PLEX may be an adjunct or alternative therapy for patients who do not experience symptomatic improvement following steroid treatment.

Susac syndrome and pregnancy: disease management

Susac syndrome (SS) consists of a triad of vision loss, hearing loss, and encephalopathy due to autoimmune-mediated vascular endothelial injury. Herein we describe a 25-year-old previously healthy woman who presented at 20 weeks' gestation with symptoms of confusion, difficulty walking, and vision and hearing loss. She had branch-retinal artery occlusions on funduscopic examination, and sensorineural hearing loss. Additionally, non-contrast enhanced brain magnetic resonance imaging showed multiple white matter and callosal lesions consistent with ischemia. She was treated initially with aspirin, corticosteroids, and intravenous immunoglobulin with early improvement, although recurrent disease was treated with cyclophosphamide and rituximab after induction of premature delivery (at 35 weeks' gestation) to spare the fetus possible toxicity. We additionally discuss a general overview of SS, what is known about pregnancy and this disease, and issues regarding diagnostic and treatment approaches for SS during pregnancy.

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.

Treatments for neuro-ophthalmologic conditions

Neuro-ophthalmology covers disorders that fall between the cracks of Neurology and Ophthalmology. Neurologists see patients with neuro-ophthalmic disorders. Recognition of the diagnosis is difficult enough, but treatment can be challenging. This article reviews several common neuro-ophthalmic disorders, outlining their features and treatments, from retinal vascular disorders to eye movements and blepharospasm.