1.Multimodality Intravascular Imaging Assessment of Plaque Erosion versus Plaque Rupture in Patients with Acute Coronary Syndrome.
Jee Eun KWON ; Wang Soo LEE ; Gary S MINTZ ; Young Joon HONG ; Sung Yun LEE ; Ki Seok KIM ; Joo Yong HAHN ; Kothanahally S SHARATH KUMAR ; Hoyoun WON ; Seong Hyeop HYEON ; Seung Yong SHIN ; Kwang Je LEE ; Tae Ho KIM ; Chee Jeong KIM ; Sang Wook KIM
Korean Circulation Journal 2016;46(4):499-506
BACKGROUND AND OBJECTIVES: We assessed plaque erosion of culprit lesions in patients with acute coronary syndrome in real world practice. SUBJECTS AND METHODS: Culprit lesion plaque rupture or plaque erosion was diagnosed with optical coherence tomography (OCT). Intravascular ultrasound (IVUS) was used to determine arterial remodeling. Positive remodeling was defined as a remodeling index (lesion/reference EEM [external elastic membrane area) >1.05. RESULTS: A total of 90 patients who had plaque rupture showing fibrous-cap discontinuity and ruptured cavity were enrolled. 36 patients showed definite OCT-plaque erosion, while 7 patients had probable OCT-plaque erosion. Overall, 26% (11/43) of definite/probable plaque erosion had non-ST elevation myocardial infarction (NSTEMI) while 35% (15/43) had ST elevation myocardial infarction (STEMI). Conversely, 14.5% (13/90) of plaque rupture had NSTEMI while 71% (64/90) had STEMI (p<0.0001). Among plaque erosion, white thrombus was seen in 55.8% (24/43) of patients and red thrombus in 27.9% (12/43) of patients. Compared to plaque erosion, plaque rupture more often showed positive remodeling (p=0.003) with a larger necrotic core area examined by virtual histology (VH)-IVUS, while negative remodeling was prominent in plaque erosion. Overall, 65% 28/43 of plaque erosions were located in the proximal 30 mm of a culprit vessel-similar to plaque ruptures (72%, 65/90, p=0.29). CONCLUSION: Although most of plaque erosions show nearly normal coronary angiogram, modest plaque burden with negative remodeling and an uncommon fibroatheroma might be the nature of plaque erosion. Multimodality intravascular imaging with OCT and VH-IVUS showed fundamentally different pathoanatomic substrates underlying plaque rupture and erosion.
Acute Coronary Syndrome*
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Humans
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Membranes
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Myocardial Infarction
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Plaque, Atherosclerotic
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Rupture*
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Thrombosis
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Tomography, Optical Coherence
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Ultrasonography
2.Estimation of Effective Radiation Dose to the Eye Lens in Dental Cone Beam Computed Tomography
Sharath S ; Winniecia Dkhar ; Madhavan TS ; Yogesh Chhaparwal
Malaysian Journal of Medicine and Health Sciences 2020;16(No.2):145-148
Introduction: Recent advancement in technology, has significantly improved the clinical application of Cone Beam Computed Tomography in the field of dentistry. The main objective of this study is to estimate the effective dose to the eye lens in Cone Bean Computed Tomography. Method: The effective dose to the lens of the eye was estimated using Dose Area Product (DAP) values from i-CAT 17-19 Platinum CBCT scanner during the CBCT examination of either the maxilla or mandible, with an exposure parameters of 120kVp and mAs 37.07. Results: The estimated effective dose for lens of the eye is 8.0±2.49mSv for voxel size 0.2 whereas 6.21±1.55mSv for voxel size 0.25 for CBCT of Mandible and 5.74±1.73mSv for voxel size 0.2 whereas 5.28±1.35mSv for voxel size 0.25 for CBCT of Maxilla. Conclusion: The effective dose to the lens of eyes for a standard protocols 0.2voxel with 26.9 sec and 0.25 voxel with 26.9 sec in CBCT for maxilla and mandible respectively are within the threshold limit of 2.0Gy. Therefore for further reduction of the effective dose to the lens of the eyes we recommend for developing a protocol with lower radiation dose and also implement the application of using an effective protective measures such as bismuth eye shield.