A review and update on the ophthalmic implications of Susac syndrome

Successful treatment of a complete Susac syndrome in a 16-year-old boy: A case report

Key Clinical Message

We reported a pediatric case of SuS with a complete diagnosis triad. Although the optimal treatment of SS is unclear, prompt diagnosis and treatment can result in almost a complete recovery.

Abstract

Susac's syndrome (SuS) is a rare, autoimmune disorder known as a typical triad of sensorineural hearing impairment, central nervous system involvement, and multiple branch retinal artery occlusions (BRAOs). It is usually misdiagnosed or underdiagnosed because its symptoms may vary at the presentation time. Diagnosis can be established based on neuroimaging, ophthalmic examination, and audiometry, which match the clinical symptoms. SuS is very limited and rare in childhood and can be easily misdiagnosed with multiple sclerosis or acute disseminated encephalomyelitis. We report a 16-year-old boy patient with a completed SuS triad including BRAO in fluorescent angiography (FA), mild to moderate sensory neural hearing loss (SNHL), "Snowball lesions," and "pearl of string" signs in magnetic resonance imaging (MRI). Successful treatment was achieved with methylprednisolone, rituximab, azathioprine, cyclophosphamide, and plasmapheresis. SuS is a rare disorder, which rarely presents with a full triad and all the manifestations may not be present at the onset of the disease, leading to misdiagnosis or underdiagnosis. Our case is exceptional because he was in a pediatric age and presented with a complete triad of SuS which adds to the rarity of this disease. Although optimal treatment of SuS is unclear, our treatment regimen resulted in almost a complete recovery.

Fatal Presentation of Susac Syndrome in a Congenitally Deaf Patient With a Cochlear Implant

OBJECTIVE

To report a fatal case of Susac syndrome in a congenitally deaf patient with a cochlear implant and a history of migraines, emphasizing the diagnostic challenges in patients with preexisting conditions.

PATIENT

A 33-year-old male with congenital hearing loss, a cochlear implant, and chronic migraines who presented with mild subacute auditory disturbance and headaches that later progressed to severe encephalopathy.

INTERVENTION

Explantation of a non-magnetic resonance imaging (MRI) compatible cochlear implant followed by MRI, fundoscopy, and the administration of immunosuppressive medications.

MAIN OUTCOME MEASURES

Diagnosis was confirmed by characteristic MRI appearance and the presence of a hemi-retinal artery occlusion.

RESULTS

After weeks of immunosuppressive treatment, the patient died of a global cerebral ischemic event of unknown origin.

CONCLUSIONS

For patients with preexisting sensorineural hearing loss and cochlear implants, Susac syndrome poses a diagnostic challenge. Auditory disturbances in the absence of cochlear implant failure should prompt further evaluation for visual disturbances and encephalopathy. MRI and fundoscopy should be performed to detect other features of the disease.

Brain fog and vessel clogs

We present a unique case of a 36-year-old female presenting with features suggestive of bilateral combined vascular occlusion, hearing loss, and encephalopathy. Multimodal imaging was done for both eyes fundus evaluation including wide-field color fundus photography, optical coherence tomography, and fundus fluorescein angiography. After extensive ocular and systemic investigations, she was diagnosed to have Susac syndrome (SS). She was referred to a neurologist and otologist for systemic evaluation and underwent laser photocoagulation in both eyes, followed by pars plana vitrectomy in her left eye. Combined bilateral retinal vascular occlusion in association with SS is very rare.

Susac syndrome in a patient with chronic myelocytic leukemia: Consequence or coincidence?

Purpose

In this study, we report a patient who presented with both chronic myelocytic leukemia (CML) and Susac syndrome (SS).

Observations

A 45-year-old male diagnosed with CML in the blast phase sought consultation due to a deterioration in vision in his right eye. He also had hearing loss and severe migraneous headaches. Best corrected visual acuity was light perception and 20/20 in the right and left eyes, respectively. The slit lamp examination and intraocular pressure were within normal ranges for both eyes. Upon dilated fundoscopy, organized vitreous hemorrhage was observed in the right eye, while the left eye exhibited extensive sclerotic vessels with retinal neovascularization in the periphery. Ultrasound of the right eye showed tractional retinal detachment. Optical coherence tomography of the left retina showed thinning of the retina in temporal macula. Fluorescein angiography revealed a substantial nonperfused region in the peripheral left retina, accompanied by arterioarterial and arteriovenous collaterals, along with microaneurysms. MRI showed scattered foci of hyperintensity within the supratentorial white matter, mostly subcortical on T2-weighted and fluid-attenuated inversion-recovery. The patient received a diagnosis of SS and was subsequently referred to the neurology service for further assessment and potential treatment.

Conclusion and importance

SS may manifest as a presentation of CML. It is advisable to conduct investigations for SS in CML patients experiencing neurological, ophthalmological, or otological symptoms.

Susac syndrome: a case report with initial presentation of incomplete bitemporal hemianopia

Susac syndrome (SS) is a rare microangiopathy affecting the precapillary arterioles of the brain, inner ear, and retina. We present a novel case of SS, presenting as acute incomplete bitemporal field loss in addition to temporally spaced neurological and vestibulocochlear symptoms. A 39-year-old female was referred to the ophthalmology clinic with acute incomplete bitemporal hemianopia and worsening hemicrania. History revealed progressive hearing loss, subjective short-term memory impairment, and vertigo temporally spaced over the preceding 12 months. Magnetic resonance brain revealed multiple small colosal lesions and liner 'spoke' lesions. Fundus fluorescein angiography revealed multiple branch retinal artery occlusions in the right eye. Audiometry confirmed bilateral sensorineural hearing loss. Treatment included intravenous corticosteroids and rituximab. This case highlights the importance of early consideration and evaluation of SS in individuals presenting with atypical ocular disturbances, where no clear cause can be elicited, in order to limit the sequelae of disease.

RETINAL FLUORESCEIN ANGIOGRAPHY IN SUSAC SYNDROME: A SHIFTING PATTERN OF ARTERIOLAR WALL HYPERFLUORESCENCE-A REPORT OF TWO CASES

BACKGROUND

Susac syndrome consists of the triad of encephalopathy, branch retinal artery occlusion, and hearing loss and is believed to be an immune-mediated endotheliopathy. Arteriolar wall hyperfluorescence (AWH) on retinal fluorescein angiography (FA) has been described in the literature as a classic ophthalmic sign for Susac syndrome. In this article, we report a pattern of distally shifting segments of AWH on FA over time that was observed in two cases.

METHODS

Two cases of Susac syndrome are presented with an emphasis on FA findings, obtained at frequent intervals during follow-up.

RESULTS

In both cases, FA displays a shifting pattern of segments of AWH distal to the localization of the AWH observed on the previous FA.

CONCLUSION

In patients with Susac syndrome, FA plays an important role in aiding diagnosis and monitoring the efficacy of treatment and disease activity during follow-up. In these two cases, the angiography revealed how the AWH can migrate along the vessel over time. This is the first published report showing an evolving distally shifting pattern of AWH in patients with Susac syndrome.

A young soldier with Susac syndrome: a case report

Background

Susac syndrome is a rare disease with multisystem manifestations. While the exact pathogenesis is not known, it has been proposed to be an autoimmune endotheliopathy affecting the microvasculature of the brain, retina, and inner ear. The disease is characterized by a triad of encephalopathy, vision loss, and hearing loss. However, patients may not have the triad at initial presentation and present with only a single finding.

Case presentation

A 25-year-old male resident of Panu Akil presented to Combined Military Hospital Lahore with complaints of dizziness and vertigo associated with severe migraine like headaches. He experienced sudden painless loss of vision in his right eye and was admitted to the medical intensive care unit. On examination, he had right-beating nystagmus and diplopia along with scintillating scotoma. After his admission, contrast-enhanced magnetic resonance imaging (MRI) was done which showed numerous enhancing bilateral white matter internal capsule micro-infarcts indicating typical “string of pearls” sign and a snowball lesion on the corpus callosum. His fundus fluorescein angiography (FFA) did not exhibit any branched retinal artery occlusions (BRAO). Fundoscopy showed the presence of drusen spots. His pure tone audiometry was unremarkable. Based on the highly characteristic findings present on the MRI, a diagnosis of Susac syndrome was made. He was started on injection methylprednisolone 1 gm IV in 500 ml normal saline over 1 h once a day for 5 days and then once a week for 8 weeks. He was also started on tablet mycophenolate mofetil 500 mg once daily for 7 days. Patient showed marked clinical improvement afterwards.

Conclusions

Susac syndrome is a rare multisystem illness with an often insidious presentation. Patients can be misdiagnosed due to the nonspecific nature of the early complaints present in the disease. High index of suspicion is required for timely diagnosis and adequate management. Although no specific guidelines exist, management consists mainly of immunosuppressants.

Susac syndrome: The importance of an early diagnosis

A 38-year-old man who attended the emergency department with headache, accompanied by vomiting, bradypsychia and gait instability, for which he was admitted to Neurology for study. During his admission, he began to present bilateral hearing loss and blurred vision in the left eye, with areas of arterial occlusion and hyperfluorescence of the arterial wall being observed in the ophthalmological examination. As a result, he was diagnosed with Susac syndrome. He was treated with systemic corticosteroids, as well as with rituximab and subsequently, with intravenous immunoglobulins and mycophenolate mofetil. The patient managed to preserve visual acuity, with gait instability and bilateral hearing loss as sequelae. Early diagnosis of Susac syndrome is important, because a delay in the start of treatment can lead to irreversible sequelae such as deafness, blindness or neurological involvement.

Susac's syndrome - A new ocular finding and disease outcome

BACKGROUND

Susac's syndrome, a rare autoimmune vasculo-occlusive disease, may pose a diagnostic challenge and result in a devastating ocular and systemic outcome. Our study identifies a new retinal finding and evaluates disease outcome. We aimed to assess clinical and imaging findings, systemic manifestations and disease outcome in patients with ocular Susac's syndrome under immunosuppressive/immunomodulation therapies.

METHODS

Retrospective tertiary center study including patients with a diagnosis of Susac's syndrome with >12 months follow up. Medical record review including ocular, neurological and auditory clinical and imaging findings, and treatment modalities. Main outcome measures were clinical manifestations and disease outcome.

RESULTS

Seven patients (14 eyes) with a mean age of 34.1 years were included. Mean follow-up was 31.9 months (12.4-72.4). All had bilateral ocular disease. Retinal microaneurysms, a new ocular finding, were demonstrated in 5 patients and persisted at the final visit. In 5 eyes, they further extended during follow-up. All were treated with immunosuppressive drugs and 5/7 additional immunomodulation therapy. At last examination, best corrected visual acuity was >20/40 in all eyes, 1/10 eyes had visual field deterioration, no eye had active ocular disease, all patients achieved neurological stability, and 1 patient had auditory deterioration.

CONCLUSION

Retinal microaneurysms, a new ocular finding in Susac's syndrome, were present in most of our patients, indicating ischemic retinal damage. Immunosuppressive and immunomodulation therapies seem to be highly effective in the control of disease activity.

The Value of Optical Coherence Tomography Angiography (OCT-A) in Neurological Diseases

Optical coherence tomography angiography (OCT-A) was commercially introduced in 2014. OCT-A allows a fast, non-invasive, three-dimensional analysis of the retinal vasculature from the vitreoretinal interface to the choriocapillaris. The results can be evaluated separately in automated or custom-defined retinal layers. Since its introduction, OCT-A has also been used in patients with neurological diseases in order to find and characterize retinal biomarkers. Many neurological diseases have retinal manifestations, often preceding the key symptoms of the neurological disease. Anatomically and developmentally, the retina is a part of the brain. In contrast to the brain, the retina is easily accessible for imaging methods; moreover, retinal imaging is more cost-effective than brain imaging. In this review, the current knowledge about OCT-A findings and possible OCT-A biomarkers in neurological diseases is summarized and discussed regarding the value of OCT-A as a diagnostic tool in neurological diseases.

Pediatric uveitis: Role of the pediatrician

The challenges of childhood uveitis lie in the varied spectrum of its clinical presentation, the often asymptomatic nature of disease, and the evolving nature of the phenotype alongside normal physiological development. These issues can lead to delayed diagnosis which can cause significant morbidity and severe visual impairment. The most common ocular complications include cataracts, band keratopathy, glaucoma, and macular oedema, and the various associated systemic disorders can also result in extra-ophthalmic morbidity. Pediatricians have an important role to play. Their awareness of the various presentations and etiologies of uveitis in children afford the opportunity of prompt diagnosis before complications arise. Juvenile Idiopathic Arthritis (JIA) is one of the most common associated disorders seen in childhood uveitis, but there is a need to recognize other causes. In this review, different causes of uveitis are explored, including infections, autoimmune and autoinflammatory disease. As treatment is often informed by etiology, pediatricians can ensure early ophthalmological referral for children with inflammatory disease at risk of uveitis and can support management decisions for children with uveitis and possible underling multi-system inflammatory disease, thus reducing the risk of the development of irreversible sequelae.

INVESTIGATING MICROANGIOPATHY USING SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN PATIENTS WITH SUSAC SYNDROME

PURPOSE

To determine whether optical coherence tomography angiography is of diagnostic utility for Susac syndrome (SuS) by quantifying microvascular retinal changes.

METHODS

We enrolled 18 eyes of 9 healthy controls and 18 eyes of 9 patients with chronic SuS (12 had previous branch retinal artery occlusions and 6 were clinically unaffected). Images of the fovea were taken using an optical coherence tomography angiography system. Analysis included vessel density, fractal dimension, vessel diameter, and measurements of the foveal avascular zone (area, eccentricity, acircularity index, and axis ratio) in deep and superficial retinal layers.

RESULTS

Skeleton density and inner ring vessel density were significantly lower in patients with SuS (skeleton density: Susac 0.11 ± 0.01 vs. controls 0.12 ± 0.01, P = 0.027. VD: SuS 0.39 ± 0.04 vs. controls 0.42 ± 0.02, P = 0.041). Eccentricity and axis ratio were significantly higher in patients with SuS (EC: Susac 0.61 ± 0.11, controls 0.51 ± 0.10, P = 0.003; axis ratio: Susac 1.57 ± 0.28, controls 1.39 ± 0.11, P = 0.005). SuS eyes (affected and unaffected) had poorer outcomes of the remaining vascular parameters compared with controls (P > 0.05).

CONCLUSION

Optical coherence tomography angiography identified chronic microvascular changes in the eyes of patients with chronic SuS. Even clinically unaffected SuS eyes showed poorer vascular parameters. Although further research is needed, this noninvasive imaging modality seems to have the potential to serve as a valuable additive diagnostic tool.

WIDEFIELD FLUORESCEIN ANGIOGRAPHY IN THE DIAGNOSIS OF SUSAC SYNDROME

PURPOSE

To present the clinical manifestations and results of key diagnostic investigations in patients with Susac syndrome, with special emphasis on the principal role of fluorescein angiography (FA) of the peripheral retina.

METHODS

A retrospective analysis of medical records (collected 2000-2019) of 20 patients (15 women and five men), aged 20 to 51 years (mean age: 31.6 years) with complete or incomplete Susac syndrome diagnosed by an ophthalmic examination and widefield fluorescein angiography (WF-FA) by Spectralis and Optos Tx200.

RESULTS

Fluorescein angiography abnormalities included vascular changes in the posterior pole in 64.7% and in the peripheral retina in 82.4%. Widefield FA abnormalities in the peripheral retina alone were seen in 35.3% and in the posterior pole, but without peripheral vascular involvement, in 17.6%. Secondary leakage from veins was noted in 58.8%.

CONCLUSION

Widefield FA of the peripheral retina has a key role in cases of suspected Susac syndrome as it confirms the diagnosis and assesses disease activity. In addition to the characteristic findings, late-phase FA revealed leakage from veins which is not a typical sign. Patients experiencing migraine headaches may benefit from increasing awareness of neurologists and otologists who more promptly referred patients with suspected Susac syndrome for ophthalmologic evaluation and WF-FA of the peripheral retina.

Scoping review of cochlear implantation in Susac's syndrome

OBJECTIVE

Scoping review of published literature to establish clinical characteristics and audiologic outcomes in patients diagnosed with Susac's Syndrome(SS) who have undergone cochlear implantation (CI).

DATA SOURCES

All published studies of CI in SS and contribution of two of our own patients who have not been reported previously.

METHODS

A comprehensive search of MEDLINE (via PubMed) was carried out in March 2020 using the following keywords and related entry terms: Susac's Syndrome, Cochlear Implantation.

RESULTS

Our search identified a total of five case reports of CI in SS. With the addition of our two patients reported here, we analyzed characteristics and outcomes in seven patients. Mean age at implantation was 30 years old (range 19-46), with six women and one man implanted. Mean time from onset of hearing loss to implantation was 17 months (range three months to four years). Best reported postoperative speech understanding was reported via different metrics, with six of seven patients achieving open set speech scores of 90% or better, and one subject performing at 68%. Vestibular symptoms were present preoperatively in four of seven patients (57%), with vestibular testing reported in two patients, and showing vestibulopathy in one patient. No complications were reported following cochlear implantation.

CONCLUSION

Cochlear implantation is a viable option for hearing rehabilitation in patients with SS, with levels of attainment of open set speech comparable to other populations of CI candidates.

Multimodal Imaging in Susac Syndrome: A Case Report and Literature Review

Susac syndrome (SS) is a rare microangiopathy that involves arterioles of the brain, retina, and cochlea. Diagnosis is extremely difficult because of the rarity of the disease and because the signs and symptoms often occur at different times. Multidisciplinary approaches and multimodal images are mandatory for diagnosis and prompt therapy. In this report, we describe a case of SS and the application of multimodal retinal imaging to evaluate the ophthalmologic changes and to confirm diagnosis. Early diagnosis and therapy based on the associations of steroids and immunosuppressants are necessary to limit the sequelae of the disease.

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's Syndrome: An Updated Review

Susac's syndrome is a rare immune-mediated endotheliopathy that mainly affects young women. It is characterised by the presence of encephalopathy, retinal vaso-occlusive disease and hearing loss. Diagnosis is based on the clinical presentation, brain magnetic resonance imaging, retinal fluorescein angiography, and audiometry. Treatment consists of immunosuppressive therapy. This review focuses on recent developments in the diagnosis and management of the condition.

Neuro-ophthalmic manifestations of Susac syndrome

PURPOSE OF REVIEW

This review discusses general features and organ-specific presentations of Susac syndrome as well as diagnosis and treatment.

RECENT FINDINGS

Latest literature regarding demographics, new diagnostic modalities such as optical coherence tomography and treatment options for Susac syndrome are discussed in detail in this review, summarizing the most recent updated information.

SUMMARY

Susac syndrome is a rare, underdiagnosed, and often misdiagnosed disease that can lead to severe complications such as deafness, vision loss, dementia, and death. It involves the central nervous system and may mimic other neurological and neuro-ophthalmological diseases.

Use of ultra-wide field retinal imaging and optical coherence tomography angiography in the diagnosis of incomplete Susac syndrome

PURPOSE

To describe clinical findings through ultra-wide field (UWF) images and optical coherence tomography angiography (OCT-A), in Susac's syndrome (SS).

METHODS

SS patients were retrospectively analyzed in a single center. Clinical features, ultra-wide-field retinographies (UWF-PR), UWF fluorescein angiographies (UWF-FA), and optical coherence tomography angiography & en face (OCT-A/EF) were reviewed.

RESULTS

Twelve eyes from six patients with a mean follow-up of 35.66 months ± SD 36.88 were included. UWF-PR showed areas of retinal whitening and cotton-wool spots in all the eyes after acute attack. Segmentary mid peripheral arteriolitis could be observed in five eyes by UWF-FA in acute and convalescent stages. OCT-A revealed capillary density changes in all of the affected eyes. During the acute phase there was a well-preserved superficial capillary network, while deep retinal plexus showed a lower density in the affected areas. OCT-A/EF revealed deep retinal plexus drop-out and surrounding edematous retina in acute attacks, becoming atrophic over time. Conversely, superficial plexus was much less affected. Perifoveal reperfusion was seen in seven eyes after the acute attack.

CONCLUSIONS

UWF-PR/FA and OCT-A/EF might be helpful to stablish an early diagnosis and to monitor SS progression.

Complete Susac syndrome in a 22-year old male in Colombia: Case report and a review of the literature

We report the case of a 22 year-old male with a clinical picture of 4 months onset of headaches, deafness, and a decrease of vision in the left eye. His mother mentioned he also had changes in behaviour and mood. The magnetic resonance scan of the brain showed multiple hyper-intense lesions in the knee of the corpus callosum. The hearing test reported a neurosensory deafness. In the ophthalmoscopy, a retinal infarction was observed in the nerve fibre layer in the left eye, which was confirmed using optical coherence tomography. The fluorescein angiography showed multiple foci of hyperfluorescence of the arteriole walls, arteriole filling defects, and regional ischaemia foci of the choroid. These findings confirmed the presumed diagnosis of a Susac syndrome. This is one of the few cases reported in the literature of a Susac syndrome in a young man with the complete diagnostic triad, and the first in Colombia.

Rituximab in the treatment of Susac’s syndrome: Report of a case

Significance

Susac’s syndrome is a rare retinocochleocerebral immune-mediated endotheliopathy and clinically manifests as a pathognomonic triad of encephalopathy, hearing loss, and branch retinal artery occlusion. This triad is rarely present at symptom onset, thus, it is often initially misdiagnosed. To date, Susac’s syndrome has persisted as an elusive entity and there are numerous treatment regimens proposed with varying effectiveness mainly based on case series.

Purpose

To report our 12-month follow-up experience in the treatment of Susac’s syndrome with rituximab.

Case report

A 25-year-old female presenting with headache, paresthesias, tinnitus, peripheral vertigo, and a branch retinal artery occlusion. The patient had a personal history of anxiety-depressive disorder. After discarding other infectious/autoimmune conditions and magnetic resonance imaging suggestive findings of Susac’s syndrome, we observed a prompt response to the combination of intravenous immunoglobulin, corticosteroids, and rituximab.

Conclusion

A standard treatment paradigm is lacking in Susac’s syndrome as randomized controlled trials do not exist. There are no definitive scores to predict its outcome, and early diagnosis is important as the organs involved can easily become irreversibly damaged. Thus, patients with Susac’s syndrome must be treated promptly and aggressively. Our report highlights the possibility of positive long-term prognosis with an early use of rituximab. However, a systematic therapeutic approach on the basis of controlled trials is mandatory to develop a consensus.