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Optical coherence tomography (OCT) with micron-scale resolution has become a key intracoronary imaging modality in vivo, providing insights not only into mechanisms of atherosclerotic coronary artery disease, but also into the understanding of vascular response following stent implantation. Although the time-domain OCT system has some technical limitations to acquire images, the recently developed frequency-domain OCT with faster pullback speeds has simplified the procedural requirements with elimination of an occlusion balloon. This article outlines the current and future developments in OCT technology for clinical use and research. [ABSTRACT FROM AUTHOR]

Background: Delayed neointimal coverage after the implantation of a drug-eluting stent (DES) is thought to be related to their potential for developing late-stent thrombosis. However, few studies have shown which factor affects the neointimal coverage after DES implantation. We hypothesized that the extent of neointimal coverage after DES implantation is affected by the underlying lesion characteristics because arterial wall components are reported to determine the transport and distribution of the drugs. Methods: Thirty-seven coronary artery lesions treated with a single sirolimus-eluting stent (SES) were evaluated in 37 patients with stable coronary artery disease. Angioscopy was performed before, immediately after, and 6 months after stenting to examine the existence of yellow plaque, thrombus, complex plaque, and intramural hemorrhage and the degree of neointimal coverage at 6-month follow-up. This was classified either as a noncoverage group (stent struts were predominantly exposed or visible through a thin neointima) or as a coverage group (stent struts were predominantly covered by neointimal hyperplasia and thus invisible). Results: Twenty-one lesions were classified into the noncoverage group, and 16 lesions the coverage group. The frequency of preexistent yellow plaques was significantly higher in the noncoverage group than that in the coverage group (67% vs 19%, P = .007). A multivariate logistic regression analysis showed the preexistence of yellow plaque was the only independent factor behind less neointimal coverage at 6 months after SES implantation (odds ratio 19.5, 95% confidence interval 1.58-240.50, P = .020). Conclusions: The preexistence of yellow plaque may be associated with decreased neointimal coverage of SES. [Copyright &y& Elsevier]

No detailed data regarding neointimal coverage of bare-metal stents (BMSs) at 3 months after implantation was reported to date. This investigation was designed to evaluate the neointimal coverage of BMSs compared with sirolimus-eluting stents (SESs) using optical coherence tomography. A prospective optical coherence tomographic follow-up examination was performed 3 months after stent implantation for patients who underwent BMS (n = 16) or SES implantation (n = 24). Neointimal hyperplasia (NIH) thickness on each stent strut and percentage of NIH area in each cross section were measured. Malapposition of stent struts to the vessel wall and the existence of in-stent thrombi were also evaluated. There were 5,076 struts of SESs and 2,875 struts of BMSs identified. NIH thickness and percentage of NIH area in the BMS group were higher than in the SES group (351 ± 248 vs 31 ± 39 μm; p <0.0001; 45.0 ± 14% vs 10.0 ± 4%; p <0.0001, respectively). The frequency of uncovered struts was higher in the SES group than the BMS group (15% vs 0.1%; p <0.0001). Malapposed struts were observed more frequently in the SES group than the BMS group (15% vs 1.1%; p <0.0001). In conclusion, there was no difference in incidence of in-stent thrombus between the 2 groups (14% vs 0%; p = 0.23). The present study showed almost all BMS struts to be well covered at a 3-month follow-up, suggesting that patients receiving BMS stents may not require dual-antiplatelet therapy >3 months after implantation. [Copyright &y& Elsevier]

Atherosclerotic yellow plaques identified by coronary angioscopy are considered as vulnerable plaques. However, characteristics of yellow plaques are not well understood. Optical coherence tomography (OCT) provides accurate tissue characterization in vivo and has the capability to measure fibrous cap thickness covering a lipid plaque. Characteristics of yellow plaques identified by angioscopy were evaluated by OCT. We examined 205 plaques of 41 coronary arteries in 26 patients. In OCT analysis, plaques were classified as fibrous or lipid. Minimal lumen area of the plaque, arch of the lipid, and fibrous cap thickness on the lipid plaque were measured. Yellow grade of the plaque was defined as 0 (white), 1 (light yellow), 2 (medium yellow), or 3 (dark yellow) based on the angioscopy. A total of 149 plaques were diagnosed as lipid plaques. Neither the minimal lumen area nor the arch of the lipid was related to the yellow grade. There was an inverse relationship between color grade and the fibrous cap thickness (grade 0 [n = 45] 218 ± 89 μm, grade 1 [n = 40] 101 ± 8 μm, grade 2 [n = 46] 72 ± 10 μm, and grade 3 [n = 18] 40 ± 14 μm; p <0.05). Sensitivity and specificity of the angioscopy-identified yellow plaque for having a thin fibrous cap (thickness ≤110 μm) were 98% and 96%, respectively. In conclusion, angioscopy-identified yellow plaques frequently were lipid tissue with an overlying thin fibrous cap. Fibrous caps of the intense yellow plaques were very thin, and these plaques might be structurally vulnerable. [Copyright &y& Elsevier]

Objective: Progression of neointimal stent coverage (NSC) and changes in thrombus were evaluated serially by coronary angioscopy for up to 2 years after sirolimus-eluting stent (SES) implantation. Design: Serial angioscopic observations were performed in 20 segments of 20 patients at baseline, and at 6 months and 2 years after SES implantation. NSC was classified as follows: 0, uncovered struts; 1, visible struts through thin neointima; or 2, no visible struts. In each patient, maximum and minimum NSC was evaluated. Existence of thrombus was also examined. Results: The maximum NSC increased from 6 months to 2 years (1.2 (0.4) vs 1.8 (0.4), respectively, p = 0.005), while the minimum NSC did not change (0.7 (0.5) vs 0.8 (0.4), respectively, p = 0.25). The prevalence of patients with uncovered struts did not decrease from 6 months to 2 years (35% vs 20%, respectively, p = 0.29). Although there were no thrombus-related adverse events, new thrombus formation was found in one patient (5%) at the 6-month, and in four patients (20%) at the 2-year follow-up evaluations. Frequencies of thrombus inside the SES at baseline, 6 months and 2 years did not differ one from another (40%, 40% and 30%, respectively; p = NS). Conclusions: Neointimal growth inside the SES progressed heterogeneously. Uncovered struts persisted in 20% of the patients for up to 2 years and subclinical thrombus formation was not a rare phenomenon. [ABSTRACT FROM AUTHOR]

Confirming complete neointimal coverage after implantation of a drug-eluting stent is clinically important because incomplete stent coverage is responsible for late thrombosis and sudden cardiac death. Optical coherence tomography is a high-resolution (≈10 μm) imaging technique capable of detecting a thin layer of neointimal hyperplasia (NIH) inside a sirolimus-eluting stent (SES) and stent malapposition. This investigation evaluated stent exposure and malapposition 3 months after SES implantation using optical coherence tomography in a different clinical presentations, such as acute coronary syndrome (ACS) and non-ACS. Motorized optical coherence tomographic pullback (1 mm/s) was performed at 3-month follow-up to examine consecutive implanted 31 SESs in 21 lesions in 21 patients (9 with ACS and 12 with non-ACS). NIH thickness inside each strut and percent NIH area in each cross section were measured. In total, 4,516 struts in 567-mm single-stented segments were analyzed. Overall, NIH thickness and percent NIH area were 29 ± 41 μm and 10 ± 4%, respectively. Rates of exposed struts and exposed struts with malapposition were 15% and 6%, respectively. These were more frequent in patients with ACS than in those with non-ACS (18% vs 13%, p <0.0001; 8% vs 5%, p <0.005, respectively). In conclusion, neointimal coverage over a SES at 3-month follow-up is incomplete in ACS and non-ACS. Our study suggests that dual antiplatelet therapy might be continued >3 months after SES implantation. [Copyright &y& Elsevier]

Aims The neointimal coverage and intracoronary thrombi within stented segments at 6 months after implantation between sirolimus-eluting stents (SESs) and bare metal stents (BMSs) were compared by direct visualization using angioscopy. [ABSTRACT FROM PUBLISHER]

A 68-year-old man with advanced gastric cancer was admitted to our hospital for the treatment of acute myocardial infarction. Bradycardia and hypotension occurred, and we started temporary right ventricular pacing and intra-aortic balloon counterpulsation in addition to high-dose catecholamine. Intravenous thrombolysis was contraindicated because of gastric cancer with active bleeding, so we performed emergent coronary angiography. Coronary angiography showed total occlusion with large thrombi in the right coronary artery and left anterior descending coronary artery. Coronary revascularization could not be achieved, but subtotal gastrectomy was performed on hospital day 51. Preoperative laboratory data showed evidence of a hypercoagulable state and increased fibrinolysis, but these abnormalities improved after gastrectomy. We conclude that gastric cancer caused a hypercoagulable state, resulting in acute myocardial infarction with simultaneous occlusion of two main coronary arteries in this case. [ABSTRACT FROM AUTHOR]

The relationship between coronary artery disease and adhesion molecules has been investigated, but the clinical significance of adhesion markers is not clear. The aim of this study was to clarify the relationship between soluble adhesion molecules and clinical severity of stable angina. Fifty-six patients with stable angina with confirmed coronary artery disease, by coronary angiography and electrocardiography during their episodes of chest pain, were enrolled. Vascular cell adhesion molecule-1, intercellular adhesion molecule-1 and E-selectin were measured, and the relationship between adhesion molecule levels and cardiac events during the follow-up period (6 months) was evaluated. Cardiac events included non-fatal myocardial infarction, coronary revascularization (coronary artery bypass grafting or coronary angioplasty), and death of any cause. Serum levels of vascular cell adhesion molecule-1 (623 ± 131 ng/ml), and E-selectin (65 ± 26 ng/ml) were higher in the 8 patients with cardiac events than the 48 patients without cardiac events (551 ± 137, and 44 ± 21 ng/ml, respectively). There was no difference in intercellular adhesion molecule-1 levels between patients with cardiac events and those without (307 ± 133, and 246 ± 123 ng/ml). In conclusion, the risk of cardiac events is increased in patients with stable angina who have increased levels of vascular cell adhesion molecule-1 and E-selectin. [ABSTRACT FROM AUTHOR]

Helicopter emergency medical service (HEMS) has the potential to improve prognosis for acute coronary syndrome (ACS). However, adequacy and effectiveness of HEMS have not been fully evaluated. A total of 862 ACS patients transferred by emergency medical services were divided into two groups: patients transferred by HEMS (n = 171) or by ground ambulance (GA; n = 691). Among them, angiography images for 718 patients (149 in HEMS and 569 in GA group) and optical coherence tomography (OCT) images for 374 patients (75 in HEMS and 299 in GA groups) were analyzed. Additional analysis to compare 2-year cardiac mortality between groups was conducted following propensity score matching to adjust for inter-group differences. ST-segment elevation myocardial infarction (81% vs. 66%, p < 0.001) and cardiogenic shock (Killip IV; 20% vs. 10%, p < 0.001) at admission were more prevalent in HEMS than GA group. Time from admission to balloon angioplasty was shorter in HEMS group (median 54 min vs. 69 min, p < 0.001). Antegrade coronary flow was worse in HEMS group (TIMI flow grade 0 or 1; 68% vs. 51%, p < 0.001). Plaque rupture was more frequently detected by OCT in HEMS group (68% vs. 49%, p = 0.029). Following propensity score matching, the incidence of cardiac death was significantly lower in HEMS group (6.3% vs. 14.9%, p = 0.019). In conclusion, severe ACS patients requiring early reperfusion were appropriately triaged and transferred more rapidly by HEMS. Lower mortality in HEMS group after propensity score matching suggests that HEMS may improve cardiac mortality in ACS patients. [ABSTRACT FROM AUTHOR]

Abstract: Aims: Postmortem series have reported that subjects with diabetes mellitus have coronary plaques with larger necrotic cores and increased macrophage infiltration. Optical coherence tomography (OCT) is a high-resolution imaging modality that allows in vivo characterization of atherosclerotic plaques. Using OCT imaging, we compared in vivo plaque characteristics between diabetic and non-diabetic subjects. Methods: Sixty-three patients undergoing cardiac catheterization were enrolled. OCT imaging was performed in culprit coronary arteries. Assessment of plaque lipid content, fibrous cap thickness and frequency of thin-cap fibroatheroma were made independently. Macrophage density was determined from the optical signal within fibrous cap. Results: Eighty-two plaques in total were imaged (19 diabetic vs. 63 non-diabetic). There were no significant differences in frequency of lipid-rich plaques (68% vs. 71%; P =0.78), thin-cap fibroatheroma (29% vs. 36%; P =0.76) or minimum fibrous cap thickness (66.6μm vs. 62.9μm; P =0.87) between diabetic and non-diabetic patients. Fibrous cap macrophage density was higher in lipid-rich plaques (P =0.01) but showed no difference between diabetic and non-diabetic patients (5.94% vs. 5.94%; P =0.37). Conclusions: There were no significant differences in culprit vessel plaque characteristics between diabetic and non-diabetic patients presenting with coronary artery disease. This represents the first study to characterize coronary plaques in diabetic patients using OCT. [Copyright &y& Elsevier]

South Asians, and Indians in particular, are known to have a higher incidence of premature atherosclerosis and acute coronary syndromes (ACS) with worse clinical outcomes, compared to populations with different ethnic backgrounds. However, the underlying pathobiology accounting for these differences has not been fully elucidated. ACS patients who had culprit lesion optical coherence tomography (OCT) imaging were enrolled. Culprit plaque characteristics were evaluated using OCT. Among 1315 patients, 100 were South Asian, 1009 were East Asian, and 206 were White. South Asian patients were younger (South Asians vs. East Asians vs. Whites: 51.6 ± 13.4 vs. 65.4 ± 11.9 vs. 62.7 ± 11.7; p < 0.001) and more frequently presented with ST-segment elevation myocardial infarction (STEMI) (77.0% vs. 56.4% vs. 35.4%; p < 0.001). On OCT analysis after propensity group matching, plaque erosion was more frequent (57.0% vs. 38.0% vs. 50.0%; p = 0.003), the lipid index was significantly greater (2281.6 [1570.8–3160.6] vs. 1624.3 [940.9–2352.4] vs. 1303.8 [1090.0–1757.7]; p < 0.001), and the prevalence of layered plaque was significantly higher in the South Asian group than in the other two groups (52.0% vs. 30.0% vs. 34.0%; p = 0.003). Compared to East Asians and Whites, South Asians with ACS were younger and more frequently presented with STEMI. Plaque erosion was the predominant pathology for ACS in South Asians and their culprit lesions had more features of plaque vulnerability. Clinical Trial Registration: http://www.clinicaltrials.gov , NCT03479723 [Display omitted] • South Asians with ACS were younger and more frequently presented with STEMI. • Plaque erosion was the predominant pathology for ACS in South Asians. • South Asian patients had more features of plaque vulnerability in culprit lesions. [ABSTRACT FROM AUTHOR]

The development of optical coherence tomography (OCT) has revolutionized our understanding of coronary artery disease. In vivo OCT research has paralleled with advances in computational fluid dynamics, providing additional insights in the various hemodynamic factors influencing plaque growth and stability. Recent OCT studies introduced a new concept of plaque healing in relation to clinical presentation. In addition to known mechanisms of acute coronary syndromes such as plaque rupture and plaque erosion, a new classification of calcified plaque was recently reported. This review will focus on important new insights that OCT has provided in recent years into coronary plaque development, progression, and destabilization, with a focus on the role of local hemodynamics and endothelial shear stress, the layered plaque (signature of previous subclinical plaque destabilization and healing), and the calcified culprit plaque. [ABSTRACT FROM AUTHOR]

Abstract Background While preinfarction angina pectoris (pre-IA) is recognized as favorable effects on acute myocardial infarction (AMI), the detail has not been fully investigated. The aims of the current study were to clarify patient characteristics, lesion morphologies determined by optical coherence tomography (OCT), and cardiac outcomes related to pre-IA in patients with AMI. Methods Clinical data and outcomes were compared between AMI patients with pre-IA (pre-IA group, n = 507) and without pre-IA (non-pre-IA group, n = 653). Angiography and OCT findings were analyzed in patients with pre-intervention OCT and compared between groups of pre-IA (n = 219) and non-pre-IA (n = 269). Results ST-segment elevation myocardial infarction (61% vs. 75%, p < 0.001) and cardiogenic shock (8% vs. 14%, p = 0.001) were less prevalent in pre-IA group. Peak creatine kinase-MB levels were lower in pre-IA group (median 83 IU/mL vs. 126 IU/mL, p < 0.001). In pre-intervention coronary angiography findings, initial TIMI flow grade 0/1 (43% vs. 56%, p = 0.019) and Rentrop collateral circulation 0/1 (69% vs. 79%, p = 0.018) were less frequently observed in pre-IA than in non-pre-IA patients. In post-thrombectomy OCT images, plaque rupture (39% vs. 56%, p = 0.003) and red thrombi (42% vs. 54%, p = 0.027) were also less frequently observed in pre-IA group. Kaplan–Meier estimate survival curves showed that cardiac death at 12-months was lower in pre-IA group than in non-pre-IA group (6.9% vs. 10.1%, p = 0.036). Conclusions Patients with pre-IA had less severe AMI on admission, smaller infarction size, and more favorable long-term survival, which may be caused by difference of lesion morphology between patients with and without pre-IA. Highlights • Features of AMI with preinfarction angina (pre-IA) have not been fully examined. • Clinical presentation on admission was less severe in patients with pre-IA. • Initial TIMI flow grade and Rentrop collateral grade were more favorable in pre-IA. • Plaque rupture and red thrombi determined by OCT were less prevalent in pre-IA. • Cardiac mortality at 12 months was more favorable in patients with pre-IA. [ABSTRACT FROM AUTHOR]

This study aimed to examine the association between the non-invasive measurement of the brachial artery volume elastic modulus ( V ), an index of arterial stiffness, and the presence of coronary artery stenosis in patients with suspected stable coronary artery disease (CAD). A total of 135 patients with suspected stable CAD (87 men, mean age, 64 ± 12 years) underwent oscillometric measurement of the brachial artery to obtain V . Coronary angiography was thereafter carried out to diagnose CAD, defined as having ≥75 % stenosis in the epicardial coronary arteries. V was significantly higher in patients with CAD (1.94 ± 0.34 mmHg/%) than in those without CAD (1.71 ± 0.35 mmHg/%, P < 0.001). In multiple logistic regression analysis, V was an independent predictor for the presence of CAD (odds ratio 1.19 per 0.1 mmHg/% increase, 95 % CI 1.04-1.51) even after adjusting for multiple potential confounders including the Framingham risk score (FRS). The area under the curve of the receiver operating characteristic curve analysis for discriminating CAD increased significantly after the addition of V to the FRS (from 0.75 to 0.81, P = 0.034). The category-free net reclassification improvement and the integrated discrimination improvement by adding V to the FRS were 0.476 (95 % CI 0.146-0.806) and 0.086 (95 % CI 0.041-0.132), respectively. In conclusion, the brachial V was significantly associated with the presence of coronary artery stenosis. The additional measurement of V to the FRS improved the ability to identify patients with coronary artery stenosis among those with suspected stable CAD. [ABSTRACT FROM AUTHOR]

Sleep-disordered breathing (SDB) is known as a cardiovascular risk factor and has high prevalence in hypertension, which is a major risk factor of aortic dissection (AD). However, the impact of SDB on AD has not been fully clarified. The aim of this study is to elucidate the impact of SDB on AD, especially on the type of false lumen in AD. We enrolled twenty-three consecutive patients with acute AD (mean age: 66 ± 13 years). All subjects were evaluated by an ambulatory polygraphic sleep monitoring within 1 month from the onset. AD was evaluated by axial images of computed tomography. We comparatively analyzed SDB and AD. 35 % of the subjects presented severe OSA (apnea-hypopnea index: AHI ≥30). The patent false lumen group showed significantly higher systolic and diastolic blood pressure (BP) on arrival and AHI, and lower percutaneous oxygen saturation (SaO) compared with those in the thrombosed false lumen group. The prevalence of severe SDB was higher in the patent false lumen group (60 vs 15 %, p = 0.039). Systolic BP on arrival was significantly correlated with AHI ( r = 0.457, p = 0.033) and the minimum SaO ( r = −0.537, p = 0.010). The present study revealed close linkage between SDB and AD, and a high prevalence of SDB among AD patients. Severe SDB was related to the development of AD, especially for the patent false lumen type through highly elevated BP which might be easily evoked in the presence of severe SDB. Repetitive occurrence of intrathoracic negative pressure also might influence the repair or closure of false lumen of AD, although the present analysis did not reach statistical significance. [ABSTRACT FROM AUTHOR]

Even in the drug-eluting stent era, diabetes mellitus (DM) patients have high incidences of restenosis and repeat revascularization after percutaneous coronary intervention. The aim of this study was to compare vascular response after stent implantation between sirolimus-eluting stent (SES) and paclitaxel-eluting stent (PES) by using optical coherence tomography (OCT) in DM patients as well as in non-DM patients. In the Japan-Drug Eluting Stents Evaluation; a Randomized Trial (J-DESsERT), the OCT sub-study enrolled 75 patients who underwent 8 months follow-up imaging after SES or PES implantation. Mean neointimal hyperplasia (NIH) thickness was significantly thinner in SES than PES in the DM group (77 ± 47 vs. 201 ± 114 μm, p < 0.001) and in the non-DM group (84 ± 37 vs. 212 ± 128 μm, p < 0.001). Unevenness of NIH thickness in longitudinal axis was significantly smaller in SES than PES in the DM group (348 ± 191 vs. 726 ± 385 μm, p < 0.001) and in the non-DM group (344 ± 174 vs. 679 ± 314 μm, p < 0.001). The percentage of uncovered struts was significantly greater in SES than PES in the DM group (24 ± 4 vs. 9 ± 14 %, p < 0.001) and in the non-DM group (16 ± 16 vs. 3 ± 4 %, p = 0.002). Compared with PES, SES showed more potent NIH inhibition in DM patients as well as in non-DM patients. [ABSTRACT FROM AUTHOR]

Objective This 8-year follow-up cohort study evaluated and compared the degree of coronary atherosclerosis in chronic kidney disease (CKD) according to the Kidney Disease: Improving Global Outcomes (KDIGO) classification using multivessel angioscopy and investigated the impact of the vulnerability of coronary arteries on the relationship between the classification and risk of acute coronary syndromes (ACS). Methods We studied 89 coronary artery disease patients who underwent angioscopic observation of multiple coronary arteries. The patients were divided into 3 groups: Risk 0, 1, and 2 were equivalent to low risk, moderately high risk, and high and severely high risk, respectively. We examined the frequencies of complex and yellow plaques. Furthermore, we followed all patients for de novo ACS, dividing into two groups according to the existence of vulnerable coronary atherosclerosis (VCA) based on angioscopic findings. Results The number of yellow plaques per vessel, maximum yellow grade, number of complex plaques per vessel, and cumulative incidence of ACS in all patients were significantly associated with Risk grade progression (p < 0.05 for trend). Among the patients with VCA, Risk 2 had a higher incidence of ACS than Risk0 (p < 0.014) and Risk 1 (p < 0.007), whereas Risk 0 and Risk 1 had similar outcomes. Among the patients without VCA, no de novo ACS events were seen regardless of the Risk group. Conclusions Coronary atherosclerosis progressed in the early stages of CKD, and once it reached to a vulnerable stage, advanced CKD patients had a synergistically increased risk of ACS. [ABSTRACT FROM AUTHOR]

Optical coherence tomography (OCT) is a fiber-optic technology that enables high-resolution intracoronary imaging. The aim of this study was to evaluate the safety and feasibility of intracoronary imaging with OCT in the clinical setting; 76 patients with coronary artery disease from 8 centers were enrolled. The OCT imaging system (ImageWire, Light Imaging Inc., Westford, Massachusetts) consists of a 0.006 inch fiber-optic core that rotates within a 0.016 inch transparent sheath. OCT imaging was performed during occlusion of the artery with a compliant balloon and continuous flushing. Intravascular ultrasound (IVUS) imaging was performed in the same segments. We assessed the safety and feasibility of the OCT imaging, compared with IVUS. Vessel occlusion time was 48.3 ± 13.5 seconds and occlusion-balloon pressure was 0.4 ± 0.1 atmospheres. Flushing with lactated Ringer’s solution was performed at a rate of 0.6 ± 0.4 ml/s. No significant adverse events, including vessel dissection or fatal arrhythmia, were observed. Procedural success rates were 97.3% by OCT and 94.5% by IVUS. The OCT image wire was able to cross 5 of 6 tight lesions that the IVUS catheter was unable to cross. Of the 98 lesions in which both OCT and IVUS were successfully performed, OCT imaging had an advantage over IVUS for visualization of the lumen border. Minimum lumen diameter and area measurements were significantly correlated between OCT and IVUS imaging (r = 0.91, p <0.0001 and r = 0.95, p <0.0001, respectively). In conclusion, this multicenter study demonstrates the safety and feasibility of OCT imaging in the clinical setting. [Copyright &y& Elsevier]