Paracentral Acute Middle Maculopathy Lesions Research Articles

Small Paracentral Acute Middle Maculopathy Lesions as Biomarker of Vascular Morbidity: Natural Course

Background: To evaluate the incidence rate of small paracentral acute middle maculopathy (PAMM) lesions in healthy fellow eyes of patients with retinal vein occlusions (RVO). Methods: Patients with unilateral branch RVO or central RVO who were followed up for at least one year were included. Fellow healthy eyes were examined with 6 mm optical coherence tomography angiography scans at baseline and at the end of the follow-up. Small resolved PAMM lesions were displayed using structural en face projections of the slab between two segmentation lines of the outer plexiform layer with 0 µm and −9 µm offset. New lesions were identified by overlaying baseline and final structural en face projections. Results: A total of 41 eyes of 41 patients (12 females and 29 males, mean age 63.5 ± 10.1 years) were included. The mean follow-up was 23.6 ± 11.4 months. Among all RVO patients, small resolved PAMM lesions in healthy fellow eyes were found in 39 patients (95.1%). In the whole cohort, the median number of PAMM lesions was 5.5 (95% CI 3.0 to 8.0) (mean 6.5 ± 5.7) at baseline, which increased statistically significantly to 5.5 (95% CI 3.8 to 8.2) (mean 6.7 ± 5.7) at the end of the follow-up period (p = 0.03). Eight (19.5%) patients demonstrated new lesions, with a median number of new lesions of 1 (ranged 1 to 2). Conclusions: Small PAMM lesions seem to be a slowly progressing retinal vascular biomarker.

PARACENTRAL ACUTE MIDDLE MACULOPATHY ASSOCIATED WITH SEVERE PLASMODIUM FALCIPARUM MALARIA.

To report a case of bilateral paracentral acute middle maculopathy (PAMM) lesions on spectral domain-optical coherence tomography (SD-OCT) secondary to severe Plasmodium falciparum malaria. Retrospective case report. SD-OCT, ultra-widefield fluorescein angiography, and OCT-angiography were performed and analysed. A 54-year-old healthy man presented with acute vision loss in both eyes few days after being diagnosed with severe Plasmodium falciparum malaria. Ophthalmoscopic examination was unremarkable but near-infrared reflectance imaging showed patchy hyporeflective areas located at the terminal tips of the venous branches. Corresponding SD-OCT demonstrated alternating bands of hyperreflectivity involving the inner nuclear layer and consistent with skip PAMM lesions. OCT-angiography illustrated corresponding flow signal loss at the level of the deep capillary plexus. Ultra-widefield fluorescein angiography showed peripheral retinal vein staining and capillary non-perfusion. PAMM may be an OCT manifestation of malaria retinopathy associated with severe Plasmodium falciparum infection.

Concomitant paracentral acute middle maculopathy and acute macular neuroretinopathy in eyes post-blunt trauma.

To analyze the imaging characteristics and the clinical course of patients showing concomitant paracentral acute middle maculopathy (PAMM) and acute macular neuroretinopathy (AMN) post-blunt trauma. PAMM and AMN lesions post-blunt trauma diagnosed on enhanced depth imaging optical coherence tomography (EDI-OCT) were recruited for the study. : Thirteen eyes of 13 individuals with a history of blunt trauma were included in the study, of whom 11 (85%) were males. Mean age of the patients was 33.62 (range 16-67) years. Mean visual acuity at presentation and the last visit was 1.67 log of minimum angle of resolution (logMAR) and 0.82 logMAR, respectively. Mean interval between trauma and imaging was 5.08 (range 1-15) days. All patients had unilateral involvement, with the right eye being involved in 10 patients (77%). All patients had concomitant PAMM and AMN lesions. : Presence of coincident PAMM and AMN suggests a common pathophysiologic etiology, but the description of concomitant PAMM and AMN in the setting of blunt trauma to eye is hitherto unreported. Identifying AMN in a setting of PAMM requires meticulous examination of the OCT and OCTA images. It can be a cause of suboptimal visual recovery in such eyes.

Swept-source optical coherence tomography angiography metrics of retinal ischaemic perivascular lesions in patients being evaluated for carotid artery stenosis and controls

Background/aimsRetinal microvascular ischaemia may produce localised middle retinal disruption with corresponding scotoma, a phenomenon termed paracentral acute middle maculopathy (PAMM). Small chronic middle retinal atrophic lesions termed retinal ischaemic perivascular...

Paracentral Acute Middle Maculopathy in Behçet's Disease.

To report a novel presentation of bilateral paracentral acute middle maculopathy (PAMM) and peripheral vascular occlusions in Behçet's disease (BD). A retrospective case report with multimodal imaging studies of a patient with BD. A 58-year-old Chinese man presented with a paracentral scotoma, fever, arthralgias and skin rash. HLA typing revealed HLA-B51 positivity. Ophthalmic examination showed peripheral retinal hemorrhages and fluorescence angiography (FA) demonstrated vascular occlusions in the peripheral retina bilaterally. Optical coherence tomography (OCT) showed classic acute PAMM lesions in both eyes. PAMM and peripheral vascular occlusion are infrequent and unconventional presentations of BD. To the best of our knowledge, this is the first report in the ophthalmic literature of PAMM and peripheral vascular occlusion in BD.

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

Background and objectivesSpectral-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. MethodsThis 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. ResultsThe 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. ConclusionsThe 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.

Choroidal ischemia as one cardinal sign in giant cell arteritis

PurposeTo describe chorioretinal signs in a case series of Giant Cell Arteritis (GCA).MethodsThis is a multicenter retrospective observational case series with GCA that presented with a headache and an abrupt, unilateral loss in vision. Workup included temporal artery biopsies, intravenous fluorescein angiography, optical coherence tomography (OCT), optical coherence tomography angiography (OCTA), blood levels of erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP).ResultsThere are a total of 8 GCA instances presented. Average age was 74.5. (Range 68–83 years). The patients reported that one eye's visual loss had suddenly started, along with a fresh headache and other systemic symptoms. Eight patients exhibited choroidal ischemia, five paracentral acute middle maculopathy (PAMM) lesions, five cotton wool spots, four anterior ischemic optic neuropathy, and one central retinal arterial occlusion at the time of presentation. The average ESR at presentation was 68 mm/hr (range 4–110), and 4/6 individuals had a significant increase. The mean CRP level was 6.2 mg/dL (range 2.0–15.4), and the level was always over the normal range. All patients' temporal artery biopsies were positive.ConclusionAlongside PAMM lesions, cotton wool spots, anterior ischemic optic neuropathy, and central retinal artery occlusion, choroidal ischemia is a key angiographic indicator in the diagnosis of GCA. It may be crucial to recognize these typical ischemic chorioretinal signs while diagnosing GCA.

Association of Resolved Paracentral Acute Middle Maculopathy Lesions with Diabetic Retinopathy.

To evaluate the association between paracentral acute middle maculopathy (PAMM) lesions and diabetic retinopathy (DR) using optical coherence tomography angiography (OCTA). Thirteen diabetic patients without DR, 13 patients with mild nonproliferative DR (NPDR), 18 patients with moderate-to-severe NPDR, and 20 patients with proliferative DR (PDR) were included in this retrospective study. For each patient, 6 mm × 6 mm macular OCTA scans of both eyes were reviewed for the presence of acute and resolved PAMM lesions. Among diabetic patients with and without DR, 49 (94.9%) and 7 (53.8%) patients demonstrated small resolved PAMM lesions, respectively. The odds ratio for the presence of resolved PAMM lesions in the eye with DR compared to the eye of diabetic patient without DR was 21.8 (P < 0.001, 95% confidence interval 7.0-67.8). In the mild NPDR group, moderate-to-severe NPDR group, and the PDR group, 11 (84.6%), 18 (100.0%), and 20 (100.0%) patients demonstrated resolved PAMM lesions, respectively. There was a statistically significant increasing prevalence of PAMM lesions as the severity of DR increased (P < 0.001). Small resolved PAMM lesions are a common form of ischemic retinal lesions in DR.

COVID-19 Associated Choroidopathy.

The aim of the study is to report on the indocyanine green angiography (ICGA) and OCT findings in patients hospitalized for severe COVID infection. In this observational prospective monocentric cohort study, we included patients hospitalized for severe COVID infection. The main outcomes were ICGA and OCT findings. A total of 14 patients with a mean age of 58.2 ± 11.4 years and a male predominance (9/14 patients; 64%) were included. The main ICGA findings included hypofluorescent spots in 19 eyes (68%), intervortex shunts in 10 eyes (36%), and characteristic “hemangioma-like” lesions in five eyes (18%). “Hemangioma-like” lesions were both unique and unilateral, and showed no washout on the late phase of the angiogram. The main OCT findings included focal choroidal thickening in seven eyes (25%), caverns in six eyes (21%) and paracentral acute middle maculopathy lesions in one eye (4%). All patients hospitalized for severe COVID infection had anomalies on ICGA and OCT. Lesions to both retinal and choroidal vasculature were found. These anomalies could be secondary to vascular involvement related directly or indirectly to the SARS-CoV2 virus.

Total venous nature of retinal deep capillary plexus inferred by continuity of prominent middle limiting membrane sign in optical coherence tomography.

This study aimed to theoretically identify the vascular nature of the deep capillary plexus (DCP) by examining patients presenting with both paracentral acute middle maculopathy (PAMM) and prominent middle limiting membrane (p-MLM) sign and p-MLM sign alone in spectral-domain optical coherence tomography (SD-OCT). A retrospective review of the medical records of patients with retinal vein or artery occlusion from two tertiary medical centers was performed. Consecutive patients with a clinical diagnosis of all categories of retinal artery occlusion (RAO) and retinal vein occlusion (RVO) (branch or central and ischemic or non-ischemic) who had undergone SD-OCT imaging from January 2015 to May 2020 were recruited and their p-MLM signs and PAMM lesions were assessed. We included 118 patients who presented with p-MLM sign with or without PAMM lesions. Amon them, 40 were female and 78 were male, with a mean age of 61.1 years. Of the 109 patients with both p-MLM sign and PAMM lesions, 23 had branch RAO, two had branch RVO, 67 had central RAO, 13 had central RVO, and four had a combination of central RAO and central RVO. All nine patients with the p-MLM sign alone had central RVO accompanied by cystoid macular edema. In all the enrolled patients, the hyperreflective lines of the p-MLM sign were continuous, regardless of the type of PAMM lesions. In conclusion, when PAMM and p-MLM sign are examined together, further proof regarding the possible complete venous nature of the vasculature of the retinal DCP might be speculated.

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

To present select cases of paracentral acute middle maculopathy (PAMM) demonstrating progressive vascular occlusion and the ischemic cascade and illustrate scenarios in which therapeutic intervention may be considered. Perspective. Review and interpretation of selected literature, with perspective on the evaluation and management of patients with PAMM lesions. Multimodal imaging of 3 illustrative cases of PAMM are presented, including cross-sectional and en face optical coherence tomography (OCT), with progressive vascular occlusion and evidence of the ischemic cascade noted in 2 of the cases. All 3 cases showed evidence of PAMM at baseline, including perivenular PAMM in 2 cases. Progression from a mild central retinal vein occlusion (CRVO) to a more severe CRVO was noted in the first case, while the second case progressed from an incomplete to complete central retinal artery occlusion (CRAO). In the third case, there was resolution of PAMM lesions associated with partial CRAO after the patient began taking aspirin. Perivenular PAMM can be the only presenting sign of retinal vascular occlusion. In such cases, it is important to differentiate between partial CRVO and incomplete CRAO as the underlying cause. We provide guidance on making this important distinction, which plays a critical role in directing the nature and urgency of the systemic work-up. In patients with PAMM caused by partial retinal arterial occlusion, a benign empirical approach, such as low-dose aspirin (81 mg), may be reasonable to reduce the likelihood of subsequent vision loss from progression to complete arterial occlusion. A clinical trial, however, is necessary to support such a strategy.

Coincident PAMM and AMN and Insights Into a Common Pathophysiology

To analyze imaging characteristics and the clinical course of patients demonstrating coincident lesions of paracentral acute middle maculopathy (PAMM) and acute macular neuroretinopathy (AMN) in the same eye. Retrospective, observational case series. Lesions from patients presenting with coincident PAMM and AMN in the same eye were evaluated with multimodal imaging including optical coherence tomography (OCT). The association with ocular and systemic findings was also investigated. Fifteen subjects (17 eyes) were included in the study. The mean age was 44.4 ± 15.3 years and the follow-up period ranged from 1 to 32 weeks (mean, 11.9 ± 11.4 weeks). The mean visual acuity was 0.8 ± 0.6 logarithm of minimal angle of resolution (Snellen equivalent 20/126) at baseline and 0.3 ± 0.4 logarithm of minimal angle of resolution (Snellen equivalent 20/40) at the last follow-up. PAMM and AMN lesions occurred in the setting of Purtscher's retinopathy (4 eyes, 3 patients), retinal vein occlusion (7 eyes, 7 patients), central retinal artery occlusion (1 eye, 1 patient), and idiopathic retinal vasculitis (1 eye, 1 patient). In 4 eyes (3 patients), an association with other ocular disorders was not identified as evaluated with multimodal imaging. Of the total cohort, 11 eyes (64.7%) showed extension of the AMN hyperreflective bands in Henle's fiber layer with a Z-shaped morphology on OCT B-scan. The presence of coincident PAMM and AMN suggests a common pathophysiologic etiology. This may be the result of retinal vein impairment and hypoperfusion at the level of the deep retinal capillary plexus possibly leading to injury to the Müller glia or photoreceptors in Henle's fiber layer.

Clinical Characteristics of Paracentral Acute Middle Maculopathy in Eyes with Retinal Vascular Occlusion Diseases in Chinese Patients.

Aim To investigate the incidence and clinical characteristics of paracentral acute middle maculopathy (PAMM) and its relationship with prominent middle limiting membrane (p-MLM) sign in eyes with retinal artery occlusion (RAO) or retinal vein occlusion (RVO) in a Chinese clinical setting. Methods In this retrospective observational study from January 2015 to May 2020, multimodal imaging data of 807 eyes including 555 consecutive patients with RVO or 252 consecutive patients with RAO were reviewed. All patients were scanned using the spectrum-domain optical coherence tomography (OCT), and some of them underwent color fundus photography, fundus fluorescence angiography, en face OCT, and OCT angiography. Results PAMM was detected in 49 eyes of 49 RAO patients and 29 eyes of 29 RVO patients. The mean ages at presentation were 64.49 ± 13.90 years and 54.00 ± 18.48 years in RAO and RVO patients (P=0.006), respectively. Eyes with RAO were more prone to develop PAMM (19.44% [49/252] vs. 5.23% [29/555]; P < 0.001). Of the 78 eyes with PAMM, 24 eyes (7 eyes with RVO and 17 eyes with RAO) were found with p-MLM sign. An interesting phenomenon that had been overlooked before was that the hyperreflective line of the p-MLM sign was usually continuous, regardless of the type of PAMM lesion. Conclusions This series is the largest to date to describe the clinical characteristics of PAMM and p-MLM sign in Chinese patients. The incidence of PAMM and p-MLM sign in patients with RAO was relatively higher than that in patients with RVO. These signs alone probably represent milder ischemia and prompt us to carry out a comprehensive and meticulous examination to prevent the further development of the disease. In addition, the hyperreflective line of the p-MLM sign was usually continuous, which could support the totally venous nature of the retinal deep capillary plexus to some extent.

Functional and structural evolution of paracentral acute middle maculopathy

A 22-year-old healthy man awoke with a new paracentral scotoma affecting his left eye. On examination, visual acuity was 20/20 in the left eye. Microperimetry (MP) showed reduced retinal sensitivity co-localized to a characteristic band of inner nuclear layer (INL) hyperreflectivity on optical coherence tomography representing paracentral acute middle maculopathy (PAMM) (Fig. 1, upper row). Weekly assessments documented the evolution of the PAMM lesion (Fig. 1). The scotoma persisted despite some improvement in the size with MP while sequential tracked optical coherence tomography B-scans illustrated a progressive decrease in reflectivity and thickness of the corresponding INL.

Status of Choriocapillaris in Fellow Eyes of Patients With Unilateral Retinal Vein Occlusions.

To study the status of the choriocapillaris in fellow eyes of patients with unilateral retinal vein occlusions (RVOs). Thirty-two healthy eyes of patients with unilateral RVO and 16 eyes of healthy age-matched controls were included. Choriocapillaris flow voids and device-specific choriocapillaris total flow areas were quantified based on 3-mm optical coherence tomography angiography (OCTA) scans and their correlation with the number of resolved para-central acute middle maculopathy (PAMM) lesions on 6-mm OCTA scans was calculated. In fellow eyes of unilateral RVOs and in eyes of healthy individuals, the number of choriocapillaris flow voids was 20.8 ± 5.5 and 13.4 ± 5.4, respectively (P < .001), and choriocapillaris total flow area was 6.0 ± 0.34 mm2 and 6.22 ± 0.13 mm2, respectively (P = .005). The number of resolved PAMM lesions correlates significantly with the number of choriocapillaris flow voids (r = 0.44; P = .002) and with choriocapillaris total flow area (r = -0.52; P < .001). Fellow eyes of patients with unilateral RVO demonstrate a substantial decrease of perfusion in choriocapillaris, which correlates with the prevalence of small resolved PAMM lesions. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:23-28.].

Vascular Microanatomy of Small Resolved Paracentral Acute Middle Maculopathy Lesions

To study microvascular characteristics of small resolved paracentral acute middle maculopathy (PAMM) lesions in fellow eyes of patients with unilateral retinal vein occlusion (RVO). Prospective cross-sectional study. Patients with prior unilateral branch or central RVO and OCT evidence of resolved PAMM in the fellow, otherwise normal, eye were recruited prospectively and imaged with OCT angiography (OCTA). The resolved PAMM lesions were identified as focal areas of inner nuclear layer thinning over an anteriorly displaced outer plexiform layer (OPL). En face OCTA projections showing the location and size of the resolved PAMM lesions were created using 2 OPL segmentation lines with -9-μm and 0-μm offsets, and the cumulative distribution was evaluated. Anterior to the resolved PAMM lesions, vessels in the superficial vascular plexus were traced to identify small arterioles supplying the affected areas. Cumulative spatial distribution on small resolved PAMM lesions. From 24 fellow eyes of 24 patients with unilateral RVO (15 men and 9 women; mean age, 62.1 ± 13.6 years), 152 resolved PAMM lesions were identified. Of these lesions, 130 (85.5%) were found within the perifoveal region, and only 12 (7.9%) were found within the temporal quadrant. Of 28 lesions analyzed, the arteriole supplying the affected area was a single side branch of a larger vessel, with only 3 supplied by a terminal branch. Small resolved PAMM lesions in fellow eyes of patients with unilateral RVO are most prevalentin perifoveal regions supplied by side branches of low-order retinal arteries.

Association of Chronic Paracentral Acute Middle Maculopathy Lesions with Hypertension

To study changes in retinal microcirculation and the prevalence of chronic paracentral acute middle maculopathy (PAMM) lesions in patients with mild hypertension. Prospective cohort study. Twenty-seven patients (21 men and 6 women; mean age, 50.3±6.3 years) with mild hypertension and with low cardiovascular risk and 24 healthy participants (15 men and 9 women; mean age, 46.3±13.0 years) were included. The foveal avascular zone (FAZ) area and the vessel density of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) were assessed using OCT angiography (OCTA). The presence of chronic PAMM lesions was evaluated for both eyes by the revision of cross-sectional OCT images of 6-mm volume scans. A chronic or resolved PAMM lesion was defined as inner nuclear layer thinning with outer plexiform layer (OPL) disruption. Vessel density of the SCP and DCP and prevalence of chronic PAMM lesions. No difference was found between the hypertensive group and healthy group in demographic and clinical characteristics, vessel density of the SCP (48.9±2.4% and 47.8±2.0%, respectively; P= 0.92), vessel density of the DCP (54.1±3.3% and 54.0±1.8%, respectively; P= 0.93), or FAZ area (0.26±0.13 mm2 and 0.23±0.09 mm2, respectively; P= 0.37). Chronic PAMM lesions were found in 24 of 27 (88.9%) hypertensive patients and in 4 of 24 (16.7%) healthy individuals. The odds ratio for the presence of chronic PAMM lesions in patients with mild hypertension was 40.0 (P < 0.001). Chronic PAMM lesions are highly prevalent in hypertensive patients and may represent the earliest changes in retinal microcirculation in patients with mild hypertension, before changes in OCTA parameters have become apparent.

Purtscher-like retinopathy presented a honeycomb-like pattern in optical coherence topography angiography

BackgroundTo report a case of Purtscher-like retinopathy (PUR) and the optical coherence tomography (OCT) and OCT angiography (OCT-A) findings before and after treatment.Case presentationA 65-year-old male presented with acute onset of vision loss for 2 weeks. Fundus examination revealed cotton-wool spots, retinal haemorrhage, and Purtscher flecken spread around the optic disc in the right eye. He was diagnosed with Purtscher-like retinopathy because he lacked any traumatic medical history. OCT presented some band-like hyperreflective lesions at the inner nuclear layer, which are indicative of paracentral acute middle maculopathy (PAMM). OCT-A revealed apparent reduction in blood flow signal at the deep retina and choriocapillaris layers with a honeycomb-like hypointense signal pattern. After 3 months of follow-up, OCT revealed resolution of retinal oedema, but PAMM lesions remained visible. Based on OCT-A, the honeycomb-like pattern turned into a homogeneous reduction in blood flow with small patches of hypointense signal areas in the choriocapillaris.ConclusionThis case presented a new OCT-A sign in PUR with a honeycomb-like hypointense signal at the choriocapillaris layer, indicating the involvement and ischaemia of the choroid during the pathological process.

Prevalence of resolved paracentral acute middle maculopathy lesions in fellow eyes of patients with unilateral retinal vein occlusion.

To study the prevalence of resolved paracentral acute middle maculopathy (PAMM) lesions in fellow eyes of patients with unilateral retinal vein occlusion (RVO) and eyes of healthy individuals. This case-control observational study took place in a referral university medical centre. Forty-five (17 males, 28 females, 64.7±10.8years) patients with branch retinal vein occlusion (BRVO), 21 (17 males, 4 females, 68.8±11.2years) patients with central retinal vein occlusion (CRVO) and 57 healthy individuals (25 males, 32 females, 67.4±10.5years) were included. Presence of resolved PAMM lesions was evaluated by reviewing cross-sectional scans of 8-mm optical coherence tomography angiography protocol. Resolved PAMM lesion was defined as inner nuclear layer thinning with outer plexiform layer elevation. Resolved PAMM lesions were found in 32/45 (71.1%) and 15/21 (71.4%) of BRVO and CRVO patients, respectively. In healthy volunteers, resolved PAMM lesions were found in 11/57 (19.3%) individuals with bilateral involvement in 8 individuals (72.7%). RVO patients demonstrated the presence of resolved PAMM lesions in fellow eye significantly more frequently than healthy individuals (odds ratio (OR) 10.6, p<0.001, 95% CI 4.5-24.6). OR for the presence of large resolved PAMM lesions in BRVO patients and CRVO patients versus healthy individual was 12.1 (p=0.02, 95% CI 1.5-100.9) and 22.4 (p=0.005, 95% CI 2.5-200.6), respectively. Resolved PAMM lesions defined as inner nuclear layer thinning associated with outer plexiform layer elevation are highly prevalent in fellow eyes of patients with unilateral RVO. Resolved PAMM lesions may have an association with RVO.

Optical Coherence Tomography Angiography of Deep Capillary Ischemia.

Paracentral acute middle maculopathy (PAMM) is defined by the spectral-domain optical coherence tomography (OCT) finding of paracentral hyper-reflective band-like lesions of the inner nuclear layer (INL) of the macula that progress to corresponding areas of severe INL thinning. En face analysis has enabled more detailed analyses and quantifications of these lesions and has provided insights into the pathogenesis of this abnormality. While there is a wealth of demographic and anatomical data indicating that these PAMM lesions are the result of an INL infarct, OCT angiography is the first modality to provide direct evidence. Several studies have recently shown that old PAMM lesions are indeed associated with ischemia of the deep capillary retinal plexus, while acute lesions may or may not show initial perfusion of the deep capillary retinal plexus.