Paracentral Acute Middle Maculopathy and the Ischemic Cascade: Toward Interventional Management

Successful Treatment of Central Retinal Artery Occlusion With Tissue Plasminogen Activator Followed by Recurrent Retinal Ischemia

Purpose: To describe the use of intra-arterial tissue plasminogen activator (tPA) to treat central retinal artery occlusion (CRAO). Methods: A case and its findings were analyzed. Results: A 45-year-old man diagnosed with a CRAO and had cerebral angiography and treatment with intra-arterial tPA. After treatment, follow-up included optical coherence tomography (OCT), fundus photography, fluorescein angiography, and OCT angiography. The visual acuity (VA) improved from hand motions to 20/30 immediately after fibrinolysis. A vascular occlusion event the next day resulted in a decrease in VA to 20/400. After initiation of dual antiplatelet therapy, the patient's VA improved to 20/20. As the retina recovered, the evolution of retinal ischemic changes to a finding similar to paracentral acute middle maculopathy was seen on imaging. Conclusions: This is the first report describing a patient safely started on dual antiplatelet therapy that led to vision improvement after initial treatment with intra-arterial tPA for a CRAO resulted in recurrent vision loss.

Paracentral Acute Middle Maculopathy and Risk of Cardiovascular Disease, Stroke, and Death: A Longitudinal Study

PURPOSE

To evaluate the risk of acute cardiovascular events (CVE), including cardiovascular diseases, cerebrovascular diseases, and all-cause mortality in patients with paracentral acute middle maculopathy (PAMM).

DESIGN

Retrospective cohort study.

METHODS

We studied 43 individuals with optical coherence tomography-documented PAMM attending Moorfields Eye Hospital between January 2014 and June 2021. We excluded patients with preceding (<2 years) major adverse cardiac events. We stratified patients by age (<50 and ≥50 years) and whether associated with retinal vascular diseases (RVD) or isolated (iPAMM). We assessed risk factors, clinical characteristics, and visual prognosis of the patients. CVE risk was estimated using Kaplan-Meier curves, the log-rank test, and Cox proportional hazards regression.

RESULTS

In young patients with iPAMM patients (n = 12), underlying predisposing factors included six (50%) sickle cell disease and five (41.6%) others, including breakthrough bleeding in pregnancy, migraine, genetic cardiomyopathy, amphetamine use; among those with PAMM + RVD (n = 12) one (9%) had a vascular disorder, and four (44.4%) oral contraceptive use. In the older group of 20 patients, 15 (75%) had at least one coronary risk factor. During a median follow-up of 14 months (range 12-54), older subjects with iPAMM had a higher risk of developing CVE than those with PAMM + RVD (P < .001). Notably, iPAMM displayed a significantly earlier peak in peri-PAMM CVE risk compared to PAMM + RVD (median: one month, range 1-40 months vs 36 months, range 12-54 months). Relative to those with PAMM + RVD, risk of CVE was significantly higher in patients with iPAMM, adjusted for age and sex (hazard ratio: 6.37, 95% confidence interval 1.68-24.14, P = .017). No young patients experienced adverse CVE. At baseline, older iPAMM patients mean best corrected visual acuity of 0.7 (0-1.8) logarithm of the minimum angle resolution, which improved significantly to 0.2 (0-1.30) logarithm of the minimum angle resolution at the latest visit (P = .033).

CONCLUSIONS

Young individuals with iPAMM have a higher prevalence of predisposing factors compared to those presenting with combined PAMM + RVD. Older patients with iPAMM had a higher risk of CVE than those with PAMM + RVD, especially in the peri-onset timeframe. This suggests the need for a prompt cardiovascular assessment to rule out systemic etiologies and optimize cardiovascular risk factors, in addition to ongoing ophthalmology input.

Central retinal artery occlusion: a stroke of the eye

Central retinal artery occlusion (CRAO), like a stroke in the brain, is a critical eye condition that requiring urgent medical attention. Patients with CRAO present with acute loss of vision and the visual prognosis is poor with low chance of spontaneous visual recovery. Moreover, the risk of developing ischaemic heart disease and cerebral stroke is increased due to the presence of underlying atherosclerotic risk factors. Currently, there is no officially recommended treatment for CRAO. This review will describe the anatomy, pathophysiology, clinical features of CRAO, as well as exploring existing and potential future approaches for managing the condition.

Retinal Ischemic Perivascular Lesions Are Associated With Myocardial Infarction in Patients With Coronary Artery Disease

PURPOSE

To evaluate the association of retinal ischemic perivascular lesions (RIPLs) with myocardial infarction (MI) among patients diagnosed with coronary artery diseases (CAD).

DESIGN

Retrospective cross-sectional study.

METHODS

Consecutive patients (317 patients) with CAD who underwent macular spectral domain optical coherence tomography (SD-OCT) were captured. Patients with CAD who developed MI were compared to those without MI. SD-OCT were reviewed by 2 independent and masked graders for the presence of RIPLs. Medical records were reviewed. Multivariate logistic regression analysis was used to evaluate the relationship between RIPLs and MI including the following covariates age, gender, smoking status, hypertension, diabetes, dyslipidemia and body mass index.

RESULTS

Of 317 patients with CAD for whom OCT scans were available to study, there were 54 (17%) with a history of MI. A higher prevalence of RIPLs was observed in the MI group compared to the non-MI group (59.3% vs 35.7%; P < .001). The presence of RIPLs was significantly associated with MI with an odds ratio of 3 (1.91-4.74; P < .001), after adjusting for age, gender, smoking status, hypertension, diabetes, dyslipidemia, and body mass index.

CONCLUSIONS

The presence of RIPLs, detected with SD-OCT, is significantly associated with MI in patients with CAD. These findings underscore the potential clinical utility of incorporating RIPL evaluation in the medical management of CAD.

Paracentral acute middle maculopathy in systemic sclerosis and subsequent branch retinal artery occlusion

Purpose

We report a case of systemic sclerosis-associated paracentral acute middle maculopathy (PAMM) in a young woman who subsequently developed branch retinal artery occlusion.

Observations

A 22-year-old woman presented with a paracentral scotoma. Optical coherence tomography (OCT) revealed bilateral paracentral acute middle maculopathy. Upon systemic examination, she was diagnosed with systemic sclerosis (SSc). She subsequently developed branch retinal artery occlusion despite vasodilator medications. After the prescription of aspirin, she did not experience a new event for one year.

Conclusion and importance

This case illustrates that SSc may affect the retinal vascular system and vision and cause PAMM. The optimal prophylaxis for patients with recurrent retinal events should be investigated in future studies.

OUTER RETINOPATHY AND MICROANGIOPATHY IN ACUTE MYELOGENOUS LEUKEMIA

PURPOSE

To describe a patient with acute myelogenous leukemia who presented with a recurrent, bilateral, outer retinopathy, before and after consolidative peripheral blood stem cell transplantation complicated by chronic graft-versus-host disease.

METHODS

This is a retrospective review of records from a 23-year-old woman with acute myelogenous leukemia who underwent comprehensive ophthalmic evaluations for over a year including chromatic perimetry and multifocal electroretinograms, imaging with spectral domain optical coherence tomography, near-infrared and short-wavelength fundus reflectance and autofluorescence, fluorescein and optical coherence tomography angiography.

RESULTS

The patient presented with recurrent, unilateral paracentral scotomas. There was localized loss of inner segment ellipsoid (EZ) and photoreceptor outer segment signals (IZ) in the pericentral retina of both eyes co-localizing with hyperreflective lesions on near-infrared reflectance. She subsequently lost vision (visual acuity = 20/200) in the right eye a year after consolidative peripheral blood stem cell transplantation complicated by steroid-resistant-chronic graft-versus-host disease. There was loss of the EZ and IZ signals corresponding to a dense central cone scotoma and multifocal electroretinograms depression. Near-infrared autofluorescence, fluorescein and optical coherence tomography angiography were within normal limits. Visual acuity (20/20) and retinal sensitivities improved with restoration of the EZ/IZ signals after oral prednisone and intravenous rituximab, but left a residual photoreceptor loss and paracentral scotoma.

CONCLUSION

We propose that an immune-mediated microangiopathy may explain the protracted, recurrent course of primary photoreceptor abnormalities in our patient, which was further complicated by manifestations of chronic graft-versus-host disease following consolidative peripheral blood stem cell transplantation. Outer retinal findings previously documented in leukemia may be explained by a similar mechanism.

Segmentation of paracentral acute middle maculopathy lesions in spectral-domain optical coherence tomography images through weakly supervised deep convolutional networks

BACKGROUND AND OBJECTIVES

Spectral-domain optical coherence tomography (SD-OCT) is a valuable tool for non-invasive imaging of the retina, allowing the discovery and visualization of localized lesions, the presence of which is associated with eye diseases. The present study introduces X-Net, a weakly supervised deep-learning framework for automated segmentation of paracentral acute middle maculopathy (PAMM) lesions in retinal SD-OCT images. Despite recent advances in the development of automatic methods for clinical analysis of OCT scans, there remains a scarcity of studies focusing on the automated detection of small retinal focal lesions. Additionally, most existing solutions depend on supervised learning, which can be time-consuming and require extensive image labeling, whereas X-Net offers a solution to these challenges. As far as we can determine, no prior study has addressed the segmentation of PAMM lesions in SD-OCT images.

METHODS

This study leverages 133 SD-OCT retinal images, each containing instances of paracentral acute middle maculopathy lesions. A team of eye experts annotated the PAMM lesions in these images using bounding boxes. Then, labeled data were used to train a U-Net that performs pre-segmentation, producing region labels of pixel-level accuracy. To attain a highly-accurate final segmentation, we introduced X-Net, a novel neural network made up of a master and a slave U-Net. During training, it takes the expert annotated, and pixel-level pre-segment annotated images and employs sophisticated strategies to ensure the highest segmentation accuracy.

RESULTS

The proposed method was rigorously evaluated on clinical retinal images excluded from training and achieved an accuracy of 99% with a high level of similarity between the automatic segmentation and expert annotation, as demonstrated by a mean Intersection-over-Union of 0.8. Alternative methods were tested on the same data. Single-stage neural networks proved insufficient for achieving satisfactory results, confirming that more advanced solutions, such as the proposed method, are necessary. We also found that X-Net using Attention U-net for both the pre-segmentation and X-Net arms for the final segmentation shows comparable performance to the proposed method, suggesting that the proposed approach remains a viable solution even when implemented with variants of the classic U-Net.

CONCLUSIONS

The proposed method exhibits reasonably high performance, validated through quantitative and qualitative evaluations. Medical eye specialists have also verified its validity and accuracy. Thus, it could be a viable tool in the clinical assessment of the retina. Additionally, the demonstrated approach for annotating the training set has proven to be effective in reducing the expert workload.

Paracentral acute middle maculopathy in a fasting patient after cataract surgery and its response to hyperbaric oxygen therapy

INTRODUCTION

Paracentral acute middle maculopathy (PAMM) is a structural optical coherence tomography (OCT) sign secondary to ischemia in the intermediate and deep retinal vascular network, characterized by hyperreflectivity in the inner nuclear layer (INL).

AIM

Our objective is to demonstrate PAMM development following uncomplicated cataract surgery, possibly triggered by fasting and dehydration. We also aim to emphasize the potential role of hyperbaric oxygen therapy in treating PAMM.

CASE PRESENTATION

A 66-year-old man with a past medical history of Neurofibromatosis type 1 and cardiovascular disease underwent uncomplicated cataract surgery in the left eye. The patient was also fasting due to Ramadan. The patient complained of very low vision during the routine postoperative examination on the third day. His-best-corrected visual acuity (BCVA) was counting fingers at 1 meter. His-anterior and posterior segment examination was unremarkable. In infrared imaging, a large hyporeflective area was observed in the parafoveal region, and structural OCT also showed increased hyperreflectivity in the middle retinal layers corresponding to the junction of INL and outer plexiform layer (OPL) involving the entire INL which suggested PAMM. Following 14 sessions of hyperbaric oxygen therapy, the patient's BCVA increased to 0.9 on the 14th day of diagnosing PAMM.

CONCLUSION

To the best of our knowledge, this is the first case representing a patient with  PAMM triggered by fasting and cataract surgery who responded positively to hyperbaric oxygen therapy. However, triggering of PAMM by fasting is entirely unproven and that this observation occurred in a highly complex case with many other possible contributing factors. Also, the triggering of PAMM by some manipulation during surgery is equally unproven.

PARACENTRAL ACUTE MIDDLE MACULOPATHY AS AN EARLY SIGN OF WALDENSTRÖM MACROGLOBULINEMIA

PURPOSE

To report a case of paracentral acute middle maculopathy as the earliest sign of an undiagnosed, life-threatening hyperviscosity syndrome.

METHODS

A 78-year-old man with an acute paracentral scotoma and examination findings of bilateral arteriolar tortuosity and unilateral paracentral acute middle maculopathy.

RESULTS

Work-up revealed anemia and elevated serum viscosity. Protein electrophoresis demonstrated an immunoglobulin M kappa monoclonal protein spike, and bone marrow biopsy confirmed an immunoglobulin M gammopathy consistent with Waldenström macroglobulinemia. Systemic chemotherapy was initiated.

CONCLUSION

This case demonstrates typical optical coherence tomography findings of paracentral acute middle maculopathy, which led to the diagnosis of a rare lymphoproliferative disorder. This highlights the importance of a prompt work-up for paracentral acute middle maculopathy to detect underlying systemic diseases, including hyperviscosity syndromes.

Paracentral acute middle maculopathy presenting as a sign of impending central retinal artery occlusion: a case report

BACKGROUND

To report a case of paracentral acute middle maculopathy (PAMM) that progressed to central retinal artery occlusion (CRAO) on spectral domain-optical coherence tomography (SD-OCT).

CASE PRESENTATION

A 63-year-old male presented with a paracentral scotoma that began several days ago. His past medical history consisted of third-degree atrioventricular heart block requiring a pacemaker. Giant cell arteritis was unlikely given the patient's labs, demographics and review of systems. SD-OCT revealed a characteristic hyperreflective band in the inner nuclear layer consistent with PAMM in his left eye. Fluorescein angiography was obtained and was unremarkable. Five days later, the patient developed no light perception in the left eye. SD-OCT showed a diffuse inner retinal hyperreflectivity consistent with CRAO.

CONCLUSION

PAMM can be a harbinger event for complete CRAO. Complete stroke evaluation should be performed to prevent a cerebrovascular event or progression to complete blindness in the involved eye.

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.

Acute retinal ischaemia associated with paracentral acute middle maculopathy detected on multimodal imaging: a premonitory sign of severe carotid occlusive disease

A man in his 60s presented with a subacute paracentral scotoma and preserved visual acuity in the left eye. He was found to have a very subtle area of deep retinal whitening at the macula and multiple retinal cholesterol emboli. Optical coherence tomography (OCT) with En face imaging revealed globular paracentral acute middle maculopathy (PAMM). A diagnosis of PAMM associated with branch artery occlusion was made and the patient was immediately transferred to the nearest stroke centre. Investigations revealed severe carotid occlusive disease for which the patient underwent carotid endarterectomy. Paracentral scotomas in patients with little clinical findings on fundus examination should raise the suspicion for PAMM, which is easily identifiable on OCT. Eye care professionals must recognise PAMM as a possible sign of acute retinal arterial ischaemia-an ocular and systemic emergency that requires immediate referral to specialised stroke centres.

A review of the management of central retinal artery occlusion

Central retinal artery occlusion (CRAO), the ocular analog of a cerebral stroke, is an ophthalmic emergency. The visual prognosis for overall spontaneous visual recovery in CRAO is low. Furthermore, the risk of future ischemic heart disease and cerebral stroke is increased due to the underlying atherosclerotic risk factors. There is currently no guideline-endorsed treatment for CRAO. This review will describe the anatomy, pathophysiology, epidemiology, and clinical features of CRAO, and investigate the current and future management strategies.