Dumitrascu, Oana M.

Background: Whether thrombolysis improves outcomes in non-arteritic central retinal artery occlusion (naCRAO) is uncertain. We aimed to evaluate the rate of visual recovery after intra-venous thrombolysis (IVT) or intra-arterial thrombolysis (IAT) administration of tissue plasminogen activator (tPA) or urokinase among patients with naCRAO and explore the parameters affecting the final visual acuity (VA). Aim: We systematically searched six databases. Logarithm of the minimum angle of resolution (logMAR) and VA of ⩾20/100 were used to quantify visual recovery. To explore the role of other factors on visual recovery, we defined two models for studies with aggregated data (designs 1 and 2) and 16 models for individual participant data (IPD, models 1–16). Summary of Review: We included data from 771 patients out of 72 publications in nine languages. Visual improvement for ⩾0.3 logMAR was reported in 74.3% of patients who received IVT-tPA within 4.5 h (CI: 60.9–86.0%; unadjusted rate: 73.2%) and 60.0% of those who received IAT-tPA within 24 h (CI: 49.1–70.5%; unadjusted rate: 59.6%). VA of ⩾20/100 was observed among 39.0% of patients after IVT-tPA within 4.5 h and 21.9% of those with IAT-tPA within 24 h. IPD models highlighted the association between improved visual outcomes and VA at presentation, at least 2 weeks follow-up before reporting the final VA, antiplatelet therapy, and shorter symptom onset to thrombolysis window. Conclusion: Early thrombolytic therapy with tPA is associated with enhanced visual recovery in naCRAO. Future studies should refine the optimum time window for thrombolysis in naCRAO.

Introduction: Central retinal artery occlusion (CRAO) is a neurovascular emergency and acute monocular visual loss should trigger a stroke code activation. As thrombolytic therapy is considered for non-arteritic CRAO in the stroke therapeutic window, we aimed to review all telestroke encounters for acute visual loss in Mayo Clinic national telestroke network, focusing on the ocular diagnosis and the management recommendations. Hypothesis: patients evaluated via telestroke for acute visual loss are less likely to receive thrombolysis Methods: We conducted a retrospective review of the Mayo Clinic Arizona Telestroke/Teleneurology (2010-2017, 6364 encounters) and Mayo Clinic Enterprise Telestroke databases (2018-2020, 3147 encounters), searching for visits requested for acute visual loss. We recorded the subjects’ demographics, time from last seen normal to telestroke evaluation, preliminary diagnosis, and therapeutic/diagnostic recommendation. Results: From a total of 9511 audio-video telestroke encounters, 49 (0.51%) had an ocular diagnosis. Out of those, 6 patients (12.2%) had a provisional diagnosis of CRAO. 4/6 (66.6%) CRAO patients presented within 4.5h from symptom onset (median 2 hours) and none received thrombolytic therapy. All telestroke physicians recommended antiplatelet, ophthalmology consultation for diagnostic evaluation and comprehensive stroke work-up. Conclusions: Telestroke evaluations for CRAO, in routine practice, are less common than the disease prevalence would predict, suggesting that education is urgently mandated to increase the index of awareness. Even when CRAO subjects are evaluated via telestroke within 4.5 hours from symptom onset, they do not receive thrombolytic therapy nor timely ophthalmologic evaluation. Telestroke visits may benefit from the inclusion of tele-ophthalmologic consults to help with establishing the diagnosis in the narrow time-window of intravenous thrombolysis.

Introduction: Retinal imaging is a non-invasive tool to study both retinal vasculature and neurodegeneration. In this exploratory retinal curcumin-fluorescence imaging (RFI) study, we sought to determine whether retinal vascular features combined with retinal amyloid burden correlate with the neurocognitive status. Methods: We used quantitative RFI in a cohort of patients with cognitive impairment to automatically compute retinal amyloid burden. Retinal blood vessels were segmented, and the vessel tortuosity index (VTI), inflection index, and branching angle were quantified. We assessed the correlations between retinal vascular and amyloid parameters, and cognitive domain Z-scores using linear regression models. Results: Thirty-four subjects were enrolled and twenty-nine (55% female, mean age 64 ± 6 years) were included in the combined retinal amyloid and vascular analysis. Eleven subjects had normal cognition and 18 had impaired cognition. Retinal VTI was discriminated among cognitive scores. The combined proximal mid-periphery amyloid count and venous VTI index exhibited significant differences between cognitively impaired and cognitively normal subjects (0.49 ± 1.1 vs. 0.91 ± 1.4, p = 0.006), and correlated with both the Wechsler Memory Scale-IV and SF-36 mental component score Z-scores (p < 0.05). Conclusion: This pilot study showed that retinal venular VTI combined with the proximal mid-periphery amyloid count could predict verbal memory loss. Future research is needed to finesse the clinical application of this retinal imaging-based technology.

Abstract INTRODUCTION: Retinal imaging is a non-invasive tool to study retinal vasculature and neurodegeneration. Patients with mild cognitive impairment (MCI) and Alzheimer’s disease (AD)-related cognitive disorder exhibit both retinal vascular abnormalities and intraretinal accumulation of amyloid beta-protein (Aβ) plaque. Curcumin-enhanced retinal fluorescence imaging (CRFI) was recently translated as a safe imaging tool for retinal Aβ plaque quantification, holding promise as an early-stage pathological biomarker of AD. In this exploratory study, we sought to determine whether retinal vascular features combined with retinal amyloid burden correlate with the neurocognitive status.METHODS: We used scanning laser ophthalmoscopy to assess quantitative CRFI in a cohort of patients with cognitive impairment that underwent standard neuropsychological testing. Retinal blood vessels were segmented in a predefined circumpapillary region of interest. For each centerline, vessel tortuosity index, vessel inflection index and branching angle was quantified. Additionally, we automatically quantified retinal amyloid count in the supero-temporal quadrant and its subregions: posterior pole, proximal mid-periphery, and distal mid-periphery. Investigators performing quantifications were blinded to the subjects’ clinical characteristics. Linear regression models were used to assess the correlations between retinal vascular and amyloid parameters and cognitive domain Z-scores.RESULTS: In this pilot study, 34 subjects underwent automated retinal amyloid imaging and 29 subjects (55% female, mean age 64±6 years) had the combined retinal amyloid and peripapillary vascular analysis. Eleven subjects had normal cognition, 15 MCI, 2 probable AD and 1 non-AD dementia. CRFI was increased in individuals with impaired versus normal cognitive function (p 0.0012). Venous VTI was the most significant vascular parameter that differ across levels of CDR. Branching angle correlated with amyloid count in the distal mid-periphery (p=0.03), whereas vessel inflexion index correlated with posterior pole amyloid count (p=0.02). The combined proximal mid-periphery amyloid count – venous tortuosity index was found to exhibit highly significant group differences between cognitively impaired and cognitively normal subjects (0.49 ± 1.1 vs 0.91 ± 1.4, p=0.006). The combined proximal mid-periphery amyloid-venous tortuosity index also correlated with verbal memory (Wechsler Memory Scale-IV; p=0.001) and cognitive-related quality of life (SF-36 mental component score Z-scores; p=0.039).CONCLUSION: Retinal venular tortuosity discriminates across cognitive scores and in combination with proximal mid-periphery amyloid count predicts verbal memory and cognitive-related quality-of-life. Future research is needed to confirm the clinical utility of this integrated retinal imaging-based methodology.

Meningovascular neurosyphilis is a common cause of stroke in young adults, particularly when HIV co-infection is present. Contemporary screening for neurosyphilis relies on invasive testing. High resolution vessel wall imaging (HR-VW) is an emerging non-invasive tool to detect intracranial vessel wall inflammation. We report a case of multifocal acute cerebral infarctions from meningovascular neurosyphillis in which HR-VWI was instrumental in leading to the etiological diagnosis. A 32-year-old man with history of untreated HIV and polysubstance abuse presented with sudden onset vertigo. CT angiogram of the head and neck showed non-dominant left extracranial vertebral artery occlusion in the V1 segment, and multifocal areas of stenoses in V2 through V4 segments. Non-contrast brain MRI demonstrated multiple small acute infarcts in the left cerebellum, left brachium pontis, medulla and occipital lobe. Rapid plasma reagin was reactive. 3D whole-brain HR-VWI revealed concentric vessel wall contrast enhancement in the left V4 segment, suggestive of inflammation. This HR-VWI finding prompted further investigation with cerebrospinal fluid analysis that revealed reactive fluorescent treponemal antibody absorption test. The patient received high-dose intravenous Penicillin G, was restarted on highly active antiretroviral therapy, and remained neurologically stable to-date. With high spatial resolution and signal-to-noise ratio, HR-VWI allows for visualization of vessel wall inflammation in co-morbid HIV and neurosyphilis.

Introduction: Retinal vascular features predict cognitive performance and retinal imaging is a non-invasive tool to study brain health. Patients with Alzheimer’s disease (AD)-related cognitive disorders exhibit both retinal vascular abnormalities and intraretinal accumulation of amyloid-beta (Aβ) plaque. Curcumin-enhanced retinal fluorescence imaging (CRFI) was recently translated as a safe imaging tool for retinal Aβ plaque quantification. In this study, we sought to determine whether and which retinal arterial and venous parameters are predictive of retinal Aβ burden and cognitive Z-scores. Methods: We used scanning laser ophthalmoscopy with RetiaTM (Centervue, Inc) to obtain CRFI in a cohort of patients with cognitive decline. Retinal blood vessels were segmented in a predefined circumpapillary region of interest. For each centerline, vessel tortuosity index (VTI), vessel inflection index (VII), and branching angle (VBA) were quantified, independently for arteries and veins. Additionally, we automatically quantified retinal amyloid count in the supero-temporal quadrant and its subregions: posterior pole (PP), proximal mid-periphery (PMP), and distal mid-periphery (DMP). All quantifications were done blinded to the subjects’ clinical characteristics. Linear regression models were used to assess the correlations between retinal vascular and amyloid parameters. Results: 29 subjects (55% female, mean age 64±6 years) were included in the analysis: 11 had normal cognition, 16 mild cognitive impairment and 2 probable AD. Venous VTI was the only vascular parameter significantly different across levels of Clinical Dementia Rate scores and between cognitively normal and impaired. Venous VBA was a significant predictor of DMP amyloid count (p=0.03). Arterial VII significantly predicted PP amyloid count (p=0.02). VBA predicted Wechsler Adult Intelligence Scale Z-score (p=0.08). The combined VTI-PMP amyloid index significantly predicted Wechsler Memory Scale, California Verbal Learning Test and SF-36 mental component score Z-scores (p<0.05). Conclusion: Retinal venous tortuosity discriminates across cognitive scores and in combination with PMP amyloid count may predict verbal memory and related quality-of-life scores.

Background: Central retinal artery occlusion (CRAO) is a neurological and ophthalmologic emergency associated with poor visual recovery. There is a dilemma regarding the appropriate treatment, as formal guidelines are lacking. Despite being considered an ocular equivalent of cerebral infarction, the time window of intravenous (IV) thrombolysis administration for maximum efficacy and safety in CRAO remains uncertain. Objective: To critically assess the current evidence regarding the safety and effectiveness of IV thrombolysis in the treatment of patients with CRAO. Methods: The objective was addressed through the development of a critically appraised topic that included a clinical scenario, structured question, literature search strategy, critical appraisal, assessment of results, evidence summary, commentary, and bottom-line conclusions. Participants included consultant and resident neurologists, a medical librarian, and content experts in the fields of vascular neurology and ophthalmology. Results: A recent patient-level meta-analysis was selected for critical appraisal. The study compared the visual recovery rates after IV thrombolysis in CRAO against the natural history of this illness and conservative therapies (ocular massage, anterior chamber paracentesis, and/or hemodilution). Time to thrombolytic therapy administration had a significant impact on visual recovery in CRAO (P<0.001). IV thrombolysis within the first 4.5 hours after symptom onset resulted in recovery of vision in 50.0% of the patients [95% confidence interval (CI), 32.4%-67.6%]. The rate of visual recovery was nearly 3 times higher than in the natural history cohort [odds ratio, 4.7 (95% CI, 2.3-9.6); P<0.001], with a 32.3% absolute risk reduction and a number needed to treat of 4.0 (95% CI, 2.6-6.6). There was no significant difference in the recovery rate after thrombolysis compared with the natural history cohort for those patients treated after 4.5 hours. No major hemorrhages occurred after alteplase administration in this meta-analysis. Conclusions: IV thrombolysis in CRAO seems to be safe and effective within the first 4.5 hours of symptom onset. A clinical decision based on this meta-analysis alone cannot be made due to several limitations. A randomized controlled clinical trial of early IV alteplase administration in CRAO is necessary to provide evidence-based therapeutic guidance.