Deep capillary retinal ischemia and high-titer prothrombin-associated antiphospholipid antibodies: A case series of three patients

Retinal ischemic cascade: New insights into the pathophysiology and imaging findings

Retinal ischemia gives rise to a complex spectrum in which the cumulative profile of ischemia of the middle and inner retina can be highly variable. We reviewed the current knowledge on paracentral acute middle maculopathy (PAMM) pathophysiology and accompanying risk factors, the middle and inner retinal vasculature and blood flow, and the vulnerability of the middle retina in vaso-occlusive disorders. The inner nuclear layer (INL) is easily affected by slight degrees of retinal hypoperfusion and ischemia. INL infarction starts at perivenular sites, manifesting as skip PAMM lesions and a fern-like appearance in cross-sectional and en face views, respectively. With horizontal progression, INL infarction may develop into diffuse globular PAMM. If vertical progression occurs, the entire middle and inner portions of the retina can be affected. Transmural infarction of the middle and inner retina would be at the end of this spectrum. This gradient of ischemic progression resembles an ischemic cascade. We review the evidence supporting the term "retinal ischemic cascade," which encompasses a broad continuum of manifestations with roots in middle retinal infarction. With this terminology, variations in spatial and temporal progression and resolution of ischemia can also be delivered; it further enables addressing the possible associations between the middle and inner retinal ischemic patterns.

Ocular findings in asymptomatic patients with primary antiphospholipid syndrome

BACKGROUND

Primary antiphospholipid syndrome (PAPS) is characterized by the presence of antiphospholipid antibodies (aPL), repetitive fetal loss, and arterial/venous thrombosis and no association with other autoimmune rheumatic disease. Ocular involvement can also occur including retinal vascular thrombosis and neuro-ophthalmological manifestations, such as optic neuropathy and amaurosis fugax. Early detection of ocular changes is crucial to minimize functional loss.

PURPOSE

To perform a multimodal evaluation, including the use of Optical Coherence Angiotomography (OCTA), in patients with PAPS without ocular complaints and compare with healthy individuals.

METHODS

We performed a complete structural and functional ophthalmological evaluation using OCTA and microperimetry exam in patients with PAPS, followed at a tertiary Rheumatology outpatient clinic.

RESULTS

We included 104 eyes of 52 subjects [PAPS without ocular complaints (N = 26) and healthy individuals (N = 26)]. Among PAPS patients, 21 were female (80.8%) and 21 (80.8%) were Caucasians. PAPS manifestations were venous (65.4%), arterial thrombosis (34.6%), and obstetrical (34.6%) and all of them had lupus anticoagulant. Ophthalmologic findings were more frequent in PAPS compared to healthy individuals (19.2% vs. 0%, p = 0.05). The most common retinal change was paracentral acute middle maculopathy (PAMM) (3 patients, 5 eyes), followed by drusen (1 patient, 2 eyes) and pachychoroid pigment epitheliopathy (PPE) (1 patient, 1 eye). Hypertension and hyperlipidemia were present in 100% of the PAPS patients with PAMM, while only six patients (26.1%) with PAPS without PAMM presented these two risk factors together (p = 0.03).

CONCLUSIONS

We provide novel evidence that approximately 20% of our asymptomatic PAPS patients without ocular symptoms have ophthalmologic findings that require early identification and careful surveillance focusing on minimizing systemic and vascular risk factors.

Evaluation of subclinical retinal microvascular changes in systemic lupus erythematosus patients using optical coherence tomography angiography and its relationship with disease activity

Objective

This study aimed to investigate subclinical retinal microvascular changes with optical coherence tomography angiography (OCTA) in patients with systemic lupus erythematosus (SLE) and healthy controls (HCs), and to evaluate the relationship between OCTA findings and Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K).

Materials and Methods

In this study, 47 eyes of SLE and 41 eyes of healthy control (HC) were evaluated. The SLE patients were divided into two subgroups: low disease activity (LDA) (SLEDAI≤5) and high disease activity (HDA) (SLEDAI>6). The results of OCTA were compared between SLE patients and HCs as well as the SLE subgroups. The relationship between OCTA results and SLEDAI-2K was evaluated.

Results

There were no differences in foveal avascular zone (FAZ) areas between the SLE patients and HCs. Central foveal thickness (CFT) was lower in SLE patients ( p = .046). Superficial capillary plexus (SCP) vessel density (VD) in SLE patients was significantly lower only in the foveal area compared to that in HCs ( p = .006). Deep capillary plexus (DCP) VD in SLE patients was significantly lower in all areas except the temporal parafoveal area compared to that in the HCs. There was no statistically significant difference between SLE groups with LDA and HDA in FAZ or any of the other areas, including SCP and DCP. When the correlation between OCTA findings and SLEDAI-2K was examined, both SCP and DCP VD were found to be negatively correlated.

conclusions

It was observed that DCP VDs were affected in SLE patients with LDA, and SCP VDs were also affected in addition to DCP with HDA. This suggests that DCP may be the first capillary plexus to be comprised in SLE. VDs were negatively correlated with disease activity. It was concluded that OCTA can be a useful tool in assessing subclinical retinal microvascular pathology and disease activity in patients with SLE.

Vascular abnormalities in uveitis

Inflammation can involve several ocular structures, including the sclera, retina, and uvea, and cause vascular changes in these tissues. Although retinal vasculitis is the most common finding associated with uveitis involving the posterior segment, other vascular abnormalities may be seen in the retina. These include capillary nonperfusion and ischemia, vascular occlusions, preretinal neovascularization, microaneurysms and macroaneurysms, and telangiectasia. Moreover, vasoproliferative tumors and subsequent coat-like response can develop secondary to uveitis. Fluorescein angiography is ideal for the investigation of retinal vascular leakage and neovascularization, while optical coherence tomography angiography can provide depth resolved images from the superficial and deep capillary plexus and can demonstrate vascular remodeling. Choroidal vascular abnormalities primarily develop in the choriocapillaris or in the choroidal stroma and can appear as flow void in optical coherence tomography angiography and filling defect and vascular leakage in indocyanine green angiography. Extensive choriocapillaris nonperfusion in the presence of choroidal inflammation can increase the risk of choroidal neovascular membrane development. Iris vascular changes may manifest as dilation of vessels in stroma due to inflammation or rubeosis that is usually from ischemia in retinal periphery secondary to chronic inflammation. More severe forms of scleral inflammation, such as necrotizing scleritis, are associated with vascular occlusion in the deep episcleral plexus, which can lead to necrosis of sclera layer and uveal exposure.

Ophthalmologic manifestations in primary antiphospholipid syndrome patients: A cross-sectional analysis of a primary antiphospholipid syndrome cohort (APS-Rio) and systematic review of the literature

OBJECTIVE

There is a broad spectrum of eye involvement in antiphospholipid syndrome (APS). The majority of descriptions are presented as case reports that include mostly APS patients secondary to systemic lupus erythematosus (SLE), with no compelling evidence in primary APS (PAPS). This study aimed to describe ocular manifestations in our well-defined PAPS cohort (APS-Rio) and then perform a systematic literature review (SLR) of ocular manifestations in patients with APS or positivity to aPL without SLE.

METHODS

We retrospectively analyzed PAPS patients followed at our outpatient clinics. All patients fulfilled Sydney APS classification criteria (2006). We evaluated them for ocular symptoms and previous ocular diagnoses. Antiphospholipid antibodies and clinical APS manifestations were compared between patients with and without ocular manifestations. For the SLR, electronic databases were searched up to November 2019.

RESULTS

We studied 105 PAPS patients; 90.5% were female and 56.2% were Caucasian. We found ocular manifestations in 37.1% of our cohort. Thrombosis was the main criteria manifestation (95.2%) and lupus anticoagulant was the most prevalent antibody. Ophthalmologic diagnoses were present in 7 patients, with 5 having retinal vessels thromboses. Amaurosis fugax was the leading complaint, present in 30 patients. In the univariate analysis, amaurosis fugax was related to livedo (p = 0.005), Raynaud's phenomenon (p = 0.048) and the presence of anticardiolipin antibody (≥40 GPL/MPL) (p = 0.041). Hemianopia was associated with arterial hypertension (p = 0.049). In the multivariate analysis, the only association found was between livedo and amaurosis fugax (OR 4.09, 95%CI 1.5-11.11, p = 0.006). Our SLR incorporated 96 articles of ocular manifestations in patients with PAPS or positivity to aPL without SLE. Ocular findings varied from 5 to 88%, including anterior and posterior segments, orbital and neuro-ophthalmologic changes.

CONCLUSION

There is little evidence on ocular manifestations in PAPS. We described an association between livedo and amaurosis fugax. Prospective studies are needed to promote the best treatment and avoid blindness in PAPS patients.

Paracentral acute middle maculopathy and the organization of the retinal capillary plexuses

The retinal capillary vasculature serves the formidable role of supplying the metabolically active inner and middle retina. In the parafoveal region, the retinal capillary plexuses (RCP) are organized in a system of three capillary layers of varying retinal depths: the superficial capillary plexus (SCP), intermediate capillary plexus (ICP) and deep capillary plexus (DCP). While the dynamic flow through these plexuses is complex and not completely understood, current research points to a hybrid model that includes both parallel and in series components in which blood flows in a predominantly serial direction between the superficial vascular complex (SVC) and deep vascular complex (DVC). Each capillary plexus autoregulates independently, so that under most conditions the retinal vasculature supplies adequate blood flow and oxygen saturation at varying depths despite diverse environmental stressors. When the flow in the deep vascular complex (i.e. ICP and DCP) fails, an ischemic lesion referred to as Paracentral Acute Middle Maculopathy (PAMM) can be identified. PAMM is an optical coherence tomography (OCT) finding defined by the presence of a hyperreflective band at the level of the inner nuclear layer (INL) that indicates INL infarction caused by globally impaired perfusion through the retinal capillary system leading to hypoperfusion of the DVC or specifically the DCP. Patients present with an acute onset paracentral scotoma and typically experience a permanent visual defect. Lesions can be caused by a diverse set of local retinal vascular diseases and systemic disorders. PAMM is a manifestation of the retinal ischemic cascade in which the mildest forms of ischemia develop at the venular end of the DCP, i.e. perivenular PAMM, while more severe forms progress horizontally to diffusely involve the INL, and the most severe forms progress vertically to infarct the inner retina. Management is targeted toward the identification and treatment of related vasculopathic and systemic risk factors.

Paracentral acute middle maculopathy-review of the literature

Paracentral acute middle maculopathy (PAMM) is a recently identified spectral-domain optical coherence tomography (SD-OCT) finding characterized by a hyper-reflective band spanning the inner nuclear layer (INL), which typically evolves to INL atrophy in later stages. Typical clinical features include the sudden onset of one or multiple paracentral scotomas, normal or mild reduction in visual acuity, and a normal fundus appearance or a fundus with a deep grayish lesion. Although its pathophysiology is not yet fully understood, ischemia at the level of the intermediate and deep capillary plexa has been demonstrated to play a major role. Since its first description, an increasing number of publications on PAMM have been published in ophthalmology scientific journals. The purpose of this study is to provide a review of the current literature on PAMM.

[Spectrum of diseases associated with paracentral acute middle maculopathy]

Paracentral acute middle maculopathy (PAMM) is a rare disease affecting middle layers of the central retina that is seen as a focal hyperreflective band-like lesion on optical coherence tomography. Paracentral acute middle maculopathy is associated mainly with vascular diseases. Optical coherence tomography angiography (OCTA) findings confirm the ischemic nature of paracentral acute middle maculopathy.