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Tin Aung - One of the best experts on this subject based on the ideXlab platform.
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plateau iris in asian subjects with primary angle closure glaucoma
Archives of Ophthalmology, 2009Co-Authors: Rajesh S. Kumar, Visanee Tantisevi, Melissa H Y Wong, Kobkuea Laohapojanart, Orathai Chansanti, Lakshmana S Mohanram, Prin Rojanapongpun, Desmond Quek, Tin AungAbstract:Objective To determine the prevalence of plateau iris in Asian eyes with primary angle closure glaucoma (PACG) using ultrasound biomicroscopy (UBM). Methods In this cross-sectional observational study, subjects older than 40 years with PACG who had a patent laser peripheral iridotomy underwent UBM in 1 eye. Ultrasound biomicroscopy images were qualitatively analyzed using standardized criteria. Plateau iris in a quadrant was defined by anteriorly directed ciliary body, absent ciliary sulcus, steep iris root from its point of insertion followed by a downward angulation, flat iris plane, and irido-angle contact. At least 2 Quadrants had to fulfill these UBM criteria for an eye to be classified as having plateau iris. Results One hundred eleven subjects (70 from Singapore, 41 from Thailand) with PACG were recruited. The mean (SD) age was 65.6 (8.1) years, and 63.9% were female. Based on standardized UBM criteria, plateau iris was found in 36 of 111 eyes (32.4%; 95% confidence interval, 24.4%-41.6%). In these 36 eyes, quadrant-wise analysis showed 66.7% had plateau iris in 2 Quadrants; 22.2%, in 3 Quadrants; and 11.1%, in all Quadrants. Conclusions About 30% of PACG eyes with a patent laser peripheral iridotomy were found to have plateau iris on UBM, highlighting the importance of non–pupil block mechanisms in Asian individuals.
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comparison of gonioscopy and anterior segment ocular coherence tomography in detecting angle closure in different Quadrants of the anterior chamber angle
Ophthalmology, 2008Co-Authors: Lisandro M Sakata, Han T Aung, Paul J Foster, Rajesh S. Kumar, David S Friedman, Raghavan Lavanya, Tin AungAbstract:Purpose To compare the performance of gonioscopy and anterior segment (AS) optical coherence tomography (OCT) in detecting angle closure in the different Quadrants of the anterior chamber angle (ACA). Design Cross-sectional observational study. Participants Five hundred two consecutive subjects more than 50 years of age with no previous ophthalmic problems recruited from a community clinic in Singapore. Methods All subjects underwent gonioscopy and AS OCT imaging in the dark. Using gonioscopy, the ACA was graded using the Scheie system by a single examiner masked to AS OCT findings. Main Outcome Measures The ACA in a particular quadrant was classified as closed if the posterior trabecular meshwork could not be seen on gonioscopy. A closed ACA on AS OCT imaging was defined by the presence of any contact between the iris and angle wall anterior to the scleral spur. Results After excluding eyes with poor image quality, a total of 423 right eyes were included in the analysis. A closed angle in at least 1 quadrant was observed in 59% of the eyes by AS OCT and in 33% of the eyes by gonioscopy ( P Conclusions The highest rates of closed angles on gonioscopy and AS OCT images were observed in the superior quadrant. Anterior segment OCT tended to detect more closed ACAs than gonioscopy, particularly in the superior and inferior Quadrants. Variations in the iris profile and level of iridoangle contact also may explain some of the differences seen between gonioscopy and AS OCT.
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prevalence of plateau iris in primary angle closure suspects an ultrasound biomicroscopy study
Ophthalmology, 2008Co-Authors: Rajesh S. Kumar, Paul T K Chew, Lisandro M Sakata, Mani Baskaran, Swati Handa, David S Friedman, Hon Tym Wong, Raghavan Lavanya, Tin AungAbstract:Purpose To determine the prevalence of plateau iris in a cohort of primary angle closure suspects (PACSs) using ultrasound biomicroscopy (UBM). Design Cross-sectional observational study. Participants Subjects over the age of 50 years diagnosed as PACSs. Intervention Subjects were randomized to undergo laser peripheral iridotomy (LPI) in one eye. Ultrasound biomicroscopy was performed before and a week after LPI. Main Outcome Measures Ultrasound biomicroscopy images were qualitatively assessed using standardized criteria. Plateau iris was defined in a quadrant by the presence of an anteriorly directed ciliary body, an absent ciliary sulcus, a steep iris root from its point of insertion followed by a downward angulation from the corneoscleral wall, presence of a central flat iris plane, and irido-angle contact. At least 2 Quadrants had to fulfil the above criteria for an eye to be defined as plateau iris. Results Two hundred five subjects were enrolled; UBM images of 167 subjects were available for analysis. Plateau iris was found in 54 of 167 (32.3%) PACS eyes after LPI. Quadrantwise analysis showed that 44 of 167 (26.3%) eyes had plateau iris in 1 quadrant, 36 (21.5%) in 2 Quadrants, 16 (9.5%) in 3 Quadrants, and 2 (1.2%) in all 4 Quadrants. Plateau iris was most commonly observed in the superior and inferior Quadrants. Conclusions Using standardized UBM criteria, plateau iris was found in about a third of PACS eyes after LPI. Prospective longitudinal studies are required to determine the clinical significance of this finding for the management of PACSs.
Rajesh S. Kumar - One of the best experts on this subject based on the ideXlab platform.
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plateau iris in asian subjects with primary angle closure glaucoma
Archives of Ophthalmology, 2009Co-Authors: Rajesh S. Kumar, Visanee Tantisevi, Melissa H Y Wong, Kobkuea Laohapojanart, Orathai Chansanti, Lakshmana S Mohanram, Prin Rojanapongpun, Desmond Quek, Tin AungAbstract:Objective To determine the prevalence of plateau iris in Asian eyes with primary angle closure glaucoma (PACG) using ultrasound biomicroscopy (UBM). Methods In this cross-sectional observational study, subjects older than 40 years with PACG who had a patent laser peripheral iridotomy underwent UBM in 1 eye. Ultrasound biomicroscopy images were qualitatively analyzed using standardized criteria. Plateau iris in a quadrant was defined by anteriorly directed ciliary body, absent ciliary sulcus, steep iris root from its point of insertion followed by a downward angulation, flat iris plane, and irido-angle contact. At least 2 Quadrants had to fulfill these UBM criteria for an eye to be classified as having plateau iris. Results One hundred eleven subjects (70 from Singapore, 41 from Thailand) with PACG were recruited. The mean (SD) age was 65.6 (8.1) years, and 63.9% were female. Based on standardized UBM criteria, plateau iris was found in 36 of 111 eyes (32.4%; 95% confidence interval, 24.4%-41.6%). In these 36 eyes, quadrant-wise analysis showed 66.7% had plateau iris in 2 Quadrants; 22.2%, in 3 Quadrants; and 11.1%, in all Quadrants. Conclusions About 30% of PACG eyes with a patent laser peripheral iridotomy were found to have plateau iris on UBM, highlighting the importance of non–pupil block mechanisms in Asian individuals.
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comparison of gonioscopy and anterior segment ocular coherence tomography in detecting angle closure in different Quadrants of the anterior chamber angle
Ophthalmology, 2008Co-Authors: Lisandro M Sakata, Han T Aung, Paul J Foster, Rajesh S. Kumar, David S Friedman, Raghavan Lavanya, Tin AungAbstract:Purpose To compare the performance of gonioscopy and anterior segment (AS) optical coherence tomography (OCT) in detecting angle closure in the different Quadrants of the anterior chamber angle (ACA). Design Cross-sectional observational study. Participants Five hundred two consecutive subjects more than 50 years of age with no previous ophthalmic problems recruited from a community clinic in Singapore. Methods All subjects underwent gonioscopy and AS OCT imaging in the dark. Using gonioscopy, the ACA was graded using the Scheie system by a single examiner masked to AS OCT findings. Main Outcome Measures The ACA in a particular quadrant was classified as closed if the posterior trabecular meshwork could not be seen on gonioscopy. A closed ACA on AS OCT imaging was defined by the presence of any contact between the iris and angle wall anterior to the scleral spur. Results After excluding eyes with poor image quality, a total of 423 right eyes were included in the analysis. A closed angle in at least 1 quadrant was observed in 59% of the eyes by AS OCT and in 33% of the eyes by gonioscopy ( P Conclusions The highest rates of closed angles on gonioscopy and AS OCT images were observed in the superior quadrant. Anterior segment OCT tended to detect more closed ACAs than gonioscopy, particularly in the superior and inferior Quadrants. Variations in the iris profile and level of iridoangle contact also may explain some of the differences seen between gonioscopy and AS OCT.
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prevalence of plateau iris in primary angle closure suspects an ultrasound biomicroscopy study
Ophthalmology, 2008Co-Authors: Rajesh S. Kumar, Paul T K Chew, Lisandro M Sakata, Mani Baskaran, Swati Handa, David S Friedman, Hon Tym Wong, Raghavan Lavanya, Tin AungAbstract:Purpose To determine the prevalence of plateau iris in a cohort of primary angle closure suspects (PACSs) using ultrasound biomicroscopy (UBM). Design Cross-sectional observational study. Participants Subjects over the age of 50 years diagnosed as PACSs. Intervention Subjects were randomized to undergo laser peripheral iridotomy (LPI) in one eye. Ultrasound biomicroscopy was performed before and a week after LPI. Main Outcome Measures Ultrasound biomicroscopy images were qualitatively assessed using standardized criteria. Plateau iris was defined in a quadrant by the presence of an anteriorly directed ciliary body, an absent ciliary sulcus, a steep iris root from its point of insertion followed by a downward angulation from the corneoscleral wall, presence of a central flat iris plane, and irido-angle contact. At least 2 Quadrants had to fulfil the above criteria for an eye to be defined as plateau iris. Results Two hundred five subjects were enrolled; UBM images of 167 subjects were available for analysis. Plateau iris was found in 54 of 167 (32.3%) PACS eyes after LPI. Quadrantwise analysis showed that 44 of 167 (26.3%) eyes had plateau iris in 1 quadrant, 36 (21.5%) in 2 Quadrants, 16 (9.5%) in 3 Quadrants, and 2 (1.2%) in all 4 Quadrants. Plateau iris was most commonly observed in the superior and inferior Quadrants. Conclusions Using standardized UBM criteria, plateau iris was found in about a third of PACS eyes after LPI. Prospective longitudinal studies are required to determine the clinical significance of this finding for the management of PACSs.
Youlin Qiao - One of the best experts on this subject based on the ideXlab platform.
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value of multi Quadrants biopsy pooled analysis of 11 population based cervical cancer screening studies
Chinese Journal of Cancer Research, 2020Co-Authors: Yuqian Zhao, Fanghui Zhao, Xun Zhang, Wenhua Zhang, Qinjing Pan, Julia C Gage, Rengaswamy Sankaranarayanan, Youlin QiaoAbstract:Objective The accuracy of colposcopy-guided biopsy is key to the success of colposcopic triage in cervical cancer screening programs. However, there is no widely adopted biopsy guideline up to date. Our study aimed to determine whether multi-Quadrants biopsy improves the yield of cervical lesions. Methods Eleven population-based cervical cancer screening studies were conducted in China. Cytology, high-risk human papillomavirus (hrHPV) testing and visual inspection were performed for primary screening. Females positive on one or more tests were referred for colposcopy and biopsy. The proportion of detected cervical intraepithelial neoplasia (CIN)2+ and yields by quadrant lesion-targeted biopsy or 4-quadrant random biopsy were compared. Results Among 4,923 females included, 1,606 had quadrant lesion-targeted biopsy, and 3,317 had 4-quadrant random biopsy. The cumulative CIN2+ yield increased from 0.10 for only one quadrant-targeted biopsy to 0.21, 0.34, and 0.58 for at most two, three and four Quadrants targeted biopsies. Among hrHPV positive females with high-grade squamous intraepithelial lesion (HSIL)+ cytology, the cumulative CIN2+ yield of a second targeted biopsy in another quadrant was significantly increased (P<0.05). Among hrHPV-negative females, the yield of 4-quadrant random biopsies was 0.005, and the yield by lesion-targeted biopsies was 0.017. For hrHPV positive females who had 4-quadrant random biopsy, the additional CIN2+ yield for HSIL+, low-grade squamous intraepithelial lesion (LSIL) cytology, or abnormal visual inspection via acetic acid and Lugol's iodine (VIA/VILI) were 0.46, 0.11, 0.14. Conclusions A 4-quadrant random biopsy is recommended only for hrHPV positive females with HSIL cytology, and is acceptable if hrHPV positive with LSIL cytology or with abnormal VIA/VILI. Our findings add evidences for an objective and practical biopsy standard to guide colposcopy in cervical cancer screening programs in low- and middle-income countries.
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inappropriate gold standard bias in cervical cancer screening studies
International Journal of Cancer, 2007Co-Authors: Robert G Pretorius, Jerome L Belinson, Raoul J Burchette, Jennifer S Smith, Youlin QiaoAbstract:As acetic acid-aided visual inspection (VIA) and colposcopic-directed biopsy miss small ≥cervical intraepithelial neoplasia (CIN) 2, inflation of sensitivity of VIA may occur when colposcopic-directed biopsy is the gold standard for ≥CIN 2. To determine whether such inflation occurs, we reviewed 375 women with ≥CIN 2 from the Shanxi Province Cervical Cancer Screening Study II. These women had positive self or physician-collected tests for high-risk human papillomavirus or abnormal cervical cytology and had VIA followed by colposcopy with directed biopsy and endocervical curettage (ECC). If a cervical quadrant had no lesion, a random biopsy at the squamocolumnar junction within that quadrant was obtained. Sensitivity of colposcopic-directed biopsy was higher for ≥CIN 2 involving 3–4 cervical Quadrants (81.3%) than for ≥CIN 2 involving 0–2 Quadrants (49.0%, p < 0.001). Sensitivities of VIA, cytology of ≥ASC-US, ≥LSIL, and ≥HSIL were higher for ≥CIN 2 involving 3–4 Quadrants than for ≥CIN 2 involving 0–2 Quadrants. When a colposcopic-directed biopsy gold standard was compared with that of a 5-biopsy standard (which included ≥CIN 2 from colposcopic-directed biopsy, random biopsy, or ECC), the sensitivity for ≥CIN 2 of VIA was inflated by 20.0% (65.9% vs. 45.9%, p < 0.001). Sensitivities of other screening tests were not affected. Similar inflation of sensitivity of VIA was found with an endpoint of ≥CIN 3 (70.4% vs. 52.0%, p = 0.0013). Inflation of sensitivity of VIA depended upon agreement between colposcopic-directed biopsy and the screening tests as measured by kappa. Studies of VIA that used colposcopic-directed biopsy as the gold standard require reevaluation. © 2007 Wiley-Liss, Inc.
Yoshiaki Nose - One of the best experts on this subject based on the ideXlab platform.
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Poor prognosis of lowr quadrant breast carcinoma
Journal of Surgical Oncology, 1996Co-Authors: Tatsuro Kamakura, Sugimachi K, Kohei Akazawa, Yasuo Nomura, Yoshiaki NoseAbstract:Althoguh some lymphatic plexuses exist in lower audrants of the breast, there have been no investigations of whether or not carcinoma located in this region is a prognostic factor for breast cancer. Of 914 patients with carcinoma of the breast who underwent curative resection following chemo-endocrine therapy between 1982 and 1985, 149 patients had disease of the lower Quadrants. The recurrence-free survival rate was lower in patients with the lower Quadrants carcinoma than in those with carcinoma of other breast regions. MUltivariate analysis showed that a lower quadrant tumor location was a significant prognostic factor for recurrence, especially soft tissue and visceral recurrence. The worse prognosis of patients with lower quadrant carcinoma of the breast suggests the possible existence of residual or occult tumor cells after surgical resection. © 1996 Wiley-Liss, Inc.
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Poor prognosis of lowr quadrant breast carcinoma
Journal of surgical oncology, 1996Co-Authors: Tatsuro Kamakura, Kohei Akazawa, Nomura Y, K. Sugimachi, Yoshiaki NoseAbstract:Although some lymphatic plexuses exist in lower Quadrants of the breast, there have been no investigations of whether or not carcinoma located in this region is a prognostic factor for breast cancer. Of 914 patients with carcinoma of the breast who underwent curative resection following chemo-endocrine therapy between 1982 and 1985, 149 patients had disease of the lower Quadrants. The recurrence-free survival rate was lower in patients with the lower Quadrants carcinoma than in those with carcinoma of other breast regions. Multivariate analysis showed that a lower quadrant tumor location was a significant prognostic factor for recurrence, especially soft tissue and visceral recurrence. The worse prognosis of patients with lower quadrant carcinoma of the breast suggests the possible existence of residual or occult tumor cells after surgical resection.
Jin Hak Lee - One of the best experts on this subject based on the ideXlab platform.
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a new color vision test to differentiate congenital and acquired color vision defects
Ophthalmology, 2007Co-Authors: Young Joo Shin, Kyu Hyung Park, Jeong-min Hwang, Won Ryang Wee, Jin Hak LeeAbstract:Purpose To investigate the efficacy of a novel computer-controlled color test for the differentiation of congenital and acquired color vision deficiency. Design Observational cross-sectional study. Participants Thirty-one patients with congenital color vision deficiency and 134 patients with acquired color vision deficiency with a Snellen visual acuity better than 20/30 underwent an ophthalmologic examination including the Ishihara color test, Hardy-Rand-Rittler test, Nagel anomaloscopy, and the Seohan computerized hue test between June, 2003, and January, 2004. Methods To investigate the type of color vision defect, a graph of the Seohan computerized hue test was divided into 4 Quadrants and error scores in each quadrant were summated. The ratio between the sums of error scores of Quadrants I and III (Q1+Q3) and those of Quadrants II and IV (Q2+Q4) was calculated. Main Outcome Measures Error scores and ratio in quadrant analysis of the Seohan computerized hue test. Results The Seohan computerized hue test showed that the sum of Q2+Q4 was significantly higher than the sum of Q1+Q3 in congenital color vision deficiency ( P t test) and that the sum of Q2+Q4 was significantly lower than the sum of Q1+Q3 in acquired color vision deficiency ( P t test). In terms of discriminating congenital and acquired color vision deficiency, the ratio in quadrant analysis had 93.3% sensitivity and 98.5% specificity with a reference value of 1.5 by the Seohan computerized hue test (95% confidence interval). Conclusions The quadrant analysis and ratio of (Q2+Q4)/(Q1+Q3) using the Seohan computerized hue test effectively differentiated congenital and acquired color vision deficiency.
