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Quantitative assessment of choriocapillaris flow deficits and type 1 macular neovascularization growth in age-related macular degeneration
Cabral, Diogo; Fradinho, Ana C; Zhang, Yi; Zhou, Hao; Ramtohul, Prithvi; Ramakrishnan, Meera S; Pereira, Telmo; Wang, Ruikang K; Freund, K Bailey
During the past 15 years, new treatment paradigms for neovascular age-related macular degeneration (nvAMD) have evolved due to the advent of intravitreal anti-vascular endothelial growth factor (VEGF) therapy and rapid advances in retinal imaging. Recent publications describe eyes with type 1 macular neovascularization (MNV) as showing more resistance to macular atrophy than eyes with other lesion types. We sought to explore whether the perfusion status of the native choriocapillaris (CC) surrounding type 1 MNV influences its pattern of growth. To evaluate this effect, we analyzed a case series of 22 eyes from 19 nvAMD patients with type 1 MNV exhibiting growth on swept-source optical coherence tomography angiography (SS-OCTA) over a minimum follow-up of 12 months. We observed an overall weak correlation between type 1 MNV growth and CC flow deficits (FDs) average size (τ = 0.17, 95% CI [- 0.20, 0.62]) and a moderate correlation with CC FD % (τ = 0.21, 95% CI [- 0.16, 0.68]). Type 1 MNV was located beneath the fovea in most of the eyes (86%) and median visual acuity was 20/35 Snellen equivalent. Our results support that type 1 MNV recapitulates areas of CC blood flow impairment while serving to preserve foveal function.
PMCID:10220043
PMID: 37236984
ISSN: 2045-2322
CID: 5541552
Geographic Analysis of Mobile Stroke Unit Treatment in a Dense Urban Area: The New York City METRONOME Registry
Kummer, Benjamin R; Lerario, Mackenzie P; Hunter, Madeleine D; Wu, Xian; Efraim, Elizabeth S; Salehi Omran, Setareh; Chen, Monica L; Diaz, Ivan L; Sacchetti, Daniel; Lekic, Tim; Kulick, Erin R; Pishanidar, Sammy; Mir, Saad A; Zhang, Yi; Asaeda, Glenn; Navi, Babak B; Marshall, Randolph S; Fink, Matthew E
Background Mobile stroke units (MSUs) reduce time to intravenous thrombolysis in acute ischemic stroke. Whether this advantage exists in densely populated urban areas with many proximate hospitals is unclear. Methods and Results We evaluated patients from the METRONOME (Metropolitan New York Mobile Stroke) registry with suspected acute ischemic stroke who were transported by a bi-institutional MSU operating in Manhattan, New York, from October 2016 to September 2017. The comparison group included patients transported to our hospitals via conventional ambulance for acute ischemic stroke during the same hours of MSU operation (Monday to Friday, 9Â am to 5Â pm). Our exposure was MSU care, and our primary outcome was dispatch-to-thrombolysis time. We estimated mean differences in the primary outcome between both groups, adjusting for clinical, demographic, and geographic factors, including numbers of nearby designated stroke centers and population density. We identified 66 patients treated or transported by MSU and 19 patients transported by conventional ambulance. Patients receiving MSU care had significantly shorter dispatch-to-thrombolysis time than patients receiving conventional care (mean: 61.2Â versus 91.6Â minutes; P=0.001). Compared with patients receiving conventional care, patients receiving MSU care were significantly more likely to be picked up closer to a higher mean number of designated stroke centers in a 2.0-mile radius (4.8 versus 2.7, P=0.002). In multivariable analysis, MSU care was associated with a mean decrease in dispatch-to-thrombolysis time of 29.7Â minutes (95% CI, 6.9-52.5) compared with conventional care. Conclusions In a densely populated urban area with a high number of intermediary stroke centers, MSU care was associated with substantially quicker time to thrombolysis compared with conventional ambulance care.
PMID: 31795824
ISSN: 2047-9980
CID: 4252122
Profiles of Urine Drug Test in Clinical Pain Patients vs Pain Research Study Subjects
Lee, Cheng-ting; Vo, Trang T; Cohen, Abigail S; Ahmed, Shihab; Zhang, Yi; Mao, Jianren; Chen, Lucy
OBJECTIVE:To examine similarities and differences in urine drug test (UDT) results in clinical pain patients and pain subjects participating in pain research studies. DESIGN/METHODS:An observational study with retrospective chart review and data analysis. METHODS:We analyzed 1,874 UDT results obtained from 1) clinical pain patients (Clinical Group; n = 1,529) and 2) pain subjects consented to participate in pain research studies (Research Group; n = 345). Since several medications such as opioids used in pain management are drugs of abuse (DOA) and can result in a positive UDT, we specifically identified those cases of positive UDT due to nonprescribed DOA and designated these cases as positive UDT with DOA (PUD). RESULTS:We found that 1) there was a higher rate of PUD in clinical pain patients (41.3%) than in pain research study subjects (14.8%); 2) although subjects in the Research Group were informed ahead of time that UDT will be conducted as a screening test, a substantial number (14.8%) of pain research study subjects still showed PUD; 3) there were different types of DOA between clinical pain patients (cannabinoids as the top DOA) and research study subjects (cocaine as the top DOA); and 4) a common factor associated with PUD was opioid therapy in both Clinical Group and Research Group. CONCLUSION/CONCLUSIONS:These results support previous findings that PUD is a common finding in clinical pain patients, particularly in those prescribed opioid therapy, and we suggest that UDT be used as routine screening testing in pain research studies.
PMCID:4805511
PMID: 26398237
ISSN: 1526-4637
CID: 5674162
Increased pain sensitivity in chronic pain subjects on opioid therapy: a cross-sectional study using quantitative sensory testing
Zhang, Yi; Ahmed, Shihab; Vo, Trang; St Hilaire, Kristin; Houghton, Mary; Cohen, Abigail S; Mao, Jianren; Chen, Lucy
OBJECTIVE:The aim of this study was to compare the sensitivity to experimental pain of chronic pain patients on opioid therapy vs chronic pain patients on non-opioid therapy and healthy subjects by quantitative sensory testing (QST). SETTING/METHODS:There is a growing body of evidence demonstrating that chronic use of opioid drugs may alter pain sensitivity. Identifying the characteristic changes in thermal pain sensitivity in chronic opioid users will be helpful in diagnosing pain sensitivity alterations associated with chronic opioid use. METHODS:Utilizing an office-based QST technique, we examined thermal pain threshold, tolerance, and temporal summation in 172 chronic pain subjects receiving opioid therapy, 121 chronic pain subjects receiving non-opioid therapy, and 129 healthy subjects. RESULTS:In chronic pain subjects receiving opioid therapy, there were detectable differences in QST characteristics compared with both chronic pain subjects receiving non-opioid therapy and healthy subjects. Specifically, in chronic pain subjects receiving opioid therapy, 1) sensitivity to heat pain was increased; threshold to heat pain was significantly lower; 2) tolerance to supra-threshold heat pain was significantly decreased; and 3) temporal pain summation was exacerbated, as compared with chronic pain subjects receiving non-opioid therapy. In a subgroup of chronic pain subjects receiving opioid therapy with increased heat pain sensitivity, their average opioid medication dosage was significantly higher than those who had an above-average heat pain threshold. Moreover, a subset of chronic pain subjects on opioid therapy exhibited a significant decrease in diffuse noxious inhibitory control (DNIC) compared with chronic pain subjects on non-opioid therapy. CONCLUSION/CONCLUSIONS:These findings suggest that a subset of QST parameters can reflect opioid-associated thermal pain sensitivity alteration, including decreased heat pain threshold, decreased cold and heat pain tolerance, diminished DNIC, and/or exacerbated temporal summation.
PMID: 25376890
ISSN: 1526-4637
CID: 5674142
Lack of correlation between opioid dose adjustment and pain score change in a group of chronic pain patients
Chen, Lucy; Vo, Trang; Seefeld, Lindsey; Malarick, Charlene; Houghton, Mary; Ahmed, Shihab; Zhang, Yi; Cohen, Abigail; Retamozo, Cynthia; St Hilaire, Kristen; Zhang, Vivian; Mao, Jianren
UNLABELLED:Despite the increasing use of opioid analgesics for chronic pain management, it is unclear whether opioid dose escalation leads to better pain relief during chronic opioid therapy. In this study, we retrospectively analyzed clinical data collected from the Massachusetts General Hospital Center for Pain Medicine over a 7-year period. We examined 1) the impact of opioid dose adjustment (increase or decrease) on clinical pain score; 2) gender and age differences in response to opioid therapy; and 3) the influence of clinical pain conditions on the opioid analgesic efficacy. A total of 109 subjects met the criteria for data collection. We found that neither opioid dose increase, nor decrease, correlated with point changes in clinical pain score in a subset of chronic pain patients over a prolonged course of opioid therapy (an average of 704 days). This lack of correlation was consistent regardless of the type of chronic pain including neuropathic, nociceptive, or mixed pain conditions. Neither gender nor age differences showed a significant influence on the clinical response to opioid therapy in these subjects. These results suggest that dose adjustment during opioid therapy may not necessarily alter long-term clinical pain score in a group of chronic pain patients and that individualized opioid therapy based on the clinical effectiveness should be considered to optimize the treatment outcome. PERSPECTIVE/CONCLUSIONS:The study reports a relationship, or lack thereof, between opioid dose change and clinical pain score in a group of chronic pain patients. The study also calls for further investigation into the effectiveness of opioid therapy in the management of chronic nonmalignant pain conditions.
PMCID:3662976
PMID: 23452826
ISSN: 1528-8447
CID: 5674132
Safety and tolerability of early noninvasive ventilatory correction using bilevel positive airway pressure in acute ischemic stroke
Tsivgoulis, Georgios; Zhang, Yi; Alexandrov, Anne W; Harrigan, Mark R; Sisson, April; Zhao, Limin; Brethour, Mary; Cava, Luis; Balucani, Clotilde; Barlinn, Kristian; Patterson, Damon E; Giannopoulos, Sotirios; DeWolfe, Jennifer; Alexandrov, Andrei V
BACKGROUND AND PURPOSE/OBJECTIVE:Hypercapnia can induce intracranial blood-flow steal from ischemic brain tissues, and early initiation of noninvasive ventilator correction (NIVC) may improve cerebral hemodynamics in acute ischemic stroke. We sought to determine safety and tolerability of NIVC initiated on hospital admission without polysomnography study. SUBJECTS AND METHODS/METHODS:Consecutive acute ischemic stroke patients were evaluated for the presence of a proximal arterial occlusion, daytime sleepiness, or history of obstructive sleep apnea, and acceptable pulse oximetry readings while awake (96%-100% on 2 to 4 L supplemental oxygen delivered by nasal cannula). NIVC was started on hospital admission as standard of care when considered necessary by treating physicians. NIVC was initiated using bilevel positive airway pressure at 10 cmH(2)O inspiratory positive airway pressure and 5 cmH(2)O expiratory positive airway pressure in combination with 40% fraction of inspired oxygen. All potential adverse events were prospectively documented. RESULTS:Among 356 acute ischemic stroke patients (median NIHSS score, 5; interquartile range, 2-13), 64 cases (18%) received NIVC (median NIHSS score, 12; interquartile range, 6-17). Baseline stroke severity was higher and proximal arterial occlusions were more frequent in NIVC patients compared to the rest (P<0.001). NIVC was not tolerated by 4 patients (7%). Adverse events in NIVC included vomiting (n=1), aspiration pneumonia (n=1), respiratory failure/intubation (n=1), hypotension requiring pressors (n=1), and facial skin breakdown (n=3). The in-hospital mortality rate was 13% in NIVC patients and 8% in the rest (P=0.195). Neurological improvement during hospitalization tended to be greater in the NIVC group (median NIHSS score decrease, 2 points; interquartile range, 0-4) compared to the rest (median NIHSS score decrease, 1; interquartile range, 0-2; P=0.078). CONCLUSIONS:In acute ischemic stroke patients with proximal arterial occlusion and excessive sleepiness or obstructive sleep apnea, NIVC can be initiated early with good tolerability and a relatively small risk of serious complications.
PMID: 21372308
ISSN: 1524-4628
CID: 4945042