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Search Results: 1 - 10 of 11460 matches for " Anterior segment optical coherence tomography "
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Modificaciones del segmento anterior ocular posterior a iridotomía láser periférica mediante tomografía de coherencia óptica
Fernández Argones,Liamet; álvarez Cisneros,Germán; Piloto Díaz,Ibraín; Fumero González,Francisco; Padilla González,Carmen María; Vinardell Pérez,Susana; Obret Mendive,Isabel; Díaz ávila,Yuderkis;
Revista Cubana de Investigaciones Biom??dicas , 2011,
Abstract: objective: to evaluate post-laser peripheral iridotomy variations of anterior ocular segment by anterior segment optical coherence tomography. method: prospective observational case series in 30 patients (46 eyes) diagnosed with primary angle- closure suspect. the tomography was obtained pre-operative and at seven days post-operative by sl-oct heidelberg engineering. quantitative variables related to anterior segment structures were analyzed before and after the laser peripheral iridotomy treatment. results: there were no pre-operative statistical differences between quadrants. in the pos-op period all variables showed significant differences particularly at inferior and nasal quadrant, except for iris-scleral spur distance (p=0.926) and angle opening distance at 750μm (p=0.069). pos-laser changes were significant for variables related to the angle (p=0.000), anterior chamber volume (p=0.000), and anterior chamber depth (p=0.011). the average increase in post-laser anterior chamber angle was 8.7±5.9 degrees and it was correlated negatively to pre-operative iris-scleral spur distance (p=0.007), angle opening distance at 500μm (p=0.031), trabecular-iris space area at 500 μm (p=0.003), and 750μm (p= 0.026). inter-eye differences were non significant for post-operative changes. conclusion: laser iridotomy is effective to increase the anterior chamber angle, and it is associated with the increase in anterior chamber volume and central depth in primary angle- closure suspect
Boston type I keratoprosthesis-donor cornea interface evaluated by high-definition spectral-domain anterior segment optical coherence tomography
Alzaga Fernandez AG, Radcliffe NM, Sippel KC, Rosenblatt MI, Sood P, Starr CE, Ciralsky JB, D'Amico DJ, Kiss S
Clinical Ophthalmology , 2012, DOI: http://dx.doi.org/10.2147/OPTH.S34787
Abstract: oston type I keratoprosthesis-donor cornea interface evaluated by high-definition spectral-domain anterior segment optical coherence tomography Case Series (1500) Total Article Views Authors: Alzaga Fernandez AG, Radcliffe NM, Sippel KC, Rosenblatt MI, Sood P, Starr CE, Ciralsky JB, D'Amico DJ, Kiss S Published Date August 2012 Volume 2012:6 Pages 1355 - 1359 DOI: http://dx.doi.org/10.2147/OPTH.S34787 Received: 08 June 2012 Accepted: 06 July 2012 Published: 27 August 2012 Ana G Alzaga Fernandez,* Nathan M Radcliffe,* Kimberly C Sippel, Mark I Rosenblatt, Priyanka Sood, Christopher E Starr, Jessica B Ciralsky, Donald J D'Amico, Szilárd Kiss Department of Ophthalmology, Weill Cornell Medical College, New York-Presbyterian Hospital, New York, NY, USA *These authors contributed equally to this work and both are considered principal authors Background: The purpose of this study was to assess whether the resolution offered by two different, recently commercially available high-resolution, spectral-domain anterior segment optical coherence tomography (AS-OCT) instruments allows for detailed anatomic characterization of the critical device-donor cornea interface in eyes implanted with the Boston type I permanent keratoprosthesis. Methods: Eighteen eyes of 17 patients implanted with the Boston type I keratoprosthesis were included in this retrospective case series. All eyes were quantitatively evaluated using the Cirrus HD-OCT while a subset (five eyes) was also qualitatively imaged using the Spectralis Anterior Segment Module. Images from these instruments were analyzed for evidence of epithelial migration onto the anterior surface of the keratoprosthesis front plate, and presence of a vertical gap between the posterior surface of the front plate and the underlying carrier donor corneal tissue. Quantitative data was obtained utilizing the caliper function on the Cirrus HD-OCT. Results: The mean duration between AS-OCT imaging and keratoprosthesis placement was 29 months. As assessed by the Cirrus HD-OCT, 83% of eyes exhibited epithelial migration over the edge of the front plate. Fifty-six percent of the keratoprosthesis devices displayed good apposition of the device with the carrier corneal donor tissue. When a vertical gap was present (44% of eyes), the mean gap was 40 (range 8–104) microns. The Spectralis Anterior Segment Module also displayed sufficient resolution to allow for similar characterization of the device-donor cornea interface. Conclusion: Spectral-domain AS-OCT permits high resolution imaging of the keratoprosthesis device-donor cornea interface. Both the Cirrus HD-OCT and the Spectralis Anterior Segment module allowed for visualization of epithelial coverage of the device-donor cornea interface, as well as identification of physical gaps. These imaging modalities, by yielding information in regard to integration of the keratoprosthesis with surrounding corneal tissue, may help identify those at risk for keratoprosthesis-related complica
Assessment of anterior segment parameters under photopic and scotopic conditions in Indian eyes using anterior segment optical coherence tomography
Dacosta Shaun,Fernandes Gitanjali,Rajendran Babu,Janakiraman P
Indian Journal of Ophthalmology , 2008,
Abstract: Purpose: To compare the anterior segment parameters in photopic and scotopic conditions using anterior segment optical coherence tomography (AS OCT) in Indian eyes. Materials and Methods: One hundred eyes of 100 normal subjects of both sexes, aged 19 to 76 years, underwent anterior segment evaluation by AS OCT (VisanteTM OCT). Central corneal thickness (CCT), central anterior chamber depth (ACD), pupil diameter (PD) and the temporal and nasal peripheral irido-corneal angles were assessed in photopic and scotopic conditions. These anterior segment parameters were stratified for age, sex and refractive error. Results: Mean values of the parameters measured in photopic and scotopic conditions respectively were as follows: ACD (mm) 2.88 ± 0.32, 2.89 ± 0.32 (P = 0.10); nasal angle (degrees) 28.80 ± 5.91, 22.28 ± 7.50 (P < 0.001); temporal angle (degrees) 29.95 ± 6.74, 22.82 ± 8.43 (P < 0.001); pupil diameter (mm) 4.08 ± 0.91, 4.68 ± 0.92 (P < 0.001); CCT (μm) 519 ± 33.88, 519 ± 33.88. Conclusions: There was no significant difference in the ACD in photopic and scotopic conditions. While the nasal and temporal angles showed a significant decrease, the pupil diameter showed a significant increase in scotopic conditions. Mean central ACD decreased with age and was shallower in females than in males. It was highest in myopes and lowest in hypermetropes. CCT was not influenced by photopic and scotopic conditions.
Subluxed traumatic cataract: optical coherence tomography findings and clinical management
Kuriyan AE, Flynn Jr HW, Yoo SH
Clinical Ophthalmology , 2012, DOI: http://dx.doi.org/10.2147/OPTH.S37393
Abstract: bluxed traumatic cataract: optical coherence tomography findings and clinical management Case report (1092) Total Article Views Authors: Kuriyan AE, Flynn Jr HW, Yoo SH Published Date December 2012 Volume 2012:6 Pages 1997 - 1999 DOI: http://dx.doi.org/10.2147/OPTH.S37393 Received: 27 August 2012 Accepted: 22 September 2012 Published: 04 December 2012 Ajay E Kuriyan, Harry W Flynn Jr, Sonia H Yoo Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami, Miami, FL Abstract: This case report describes the optical coherence tomography (OCT) findings and clinical management of a patient with traumatic subluxed cataract. The patient presented with a traumatic subluxed cataract and vitreous prolapse into the anterior chamber. The anterior segment OCT showed vacuoles in the anterior subcapsular regions of the crystalline lens. The patient was treated with pars plana lensectomy, vitrectomy, and placement of an anterior chamber intraocular lens. The patient's best corrected visual acuity improved from hand motion at presentation to 20/25 during 3 years of follow-up. Anterior segment OCT demonstrates that the clinically visible vacuoles in traumatic cataract are located in the anterior subcapsular part of the lens. This is the first report in the literature using anterior segment OCT to visualize the subcapsular vacuolar changes in a traumatic cataract.
Angle imaging: Advances and challenges
Quek Desmond,Nongpiur Monisha,Perera Shamira,Aung Tin
Indian Journal of Ophthalmology , 2011,
Abstract: Primary angle closure glaucoma (PACG) is a major form of glaucoma in large populous countries in East and South Asia. The high visual morbidity from PACG is related to the destructive nature of the asymptomatic form of the disease. Early detection of anatomically narrow angles is important and the subsequent prevention of visual loss from PACG depends on an accurate assessment of the anterior chamber angle (ACA). This review paper discusses the advantages and limitations of newer ACA imaging technologies, namely ultrasound biomicroscopy, Scheimpflug photography, anterior segment optical coherence tomography and EyeCam, highlighting the current clinical evidence comparing these devices with each other and with clinical dynamic indentation gonioscopy, the current reference standard.
Imaging late capsular bag distension syndrome: an anterior segment optical coherence tomography study
Tan YL, Mohanram LS, Ti SE, Aung T, Perera S
Clinical Ophthalmology , 2012, DOI: http://dx.doi.org/10.2147/OPTH.S34639
Abstract: ging late capsular bag distension syndrome: an anterior segment optical coherence tomography study Case Series (1434) Total Article Views Authors: Tan YL, Mohanram LS, Ti SE, Aung T, Perera S Published Date September 2012 Volume 2012:6 Pages 1455 - 1458 DOI: http://dx.doi.org/10.2147/OPTH.S34639 Received: 05 June 2012 Accepted: 06 July 2012 Published: 06 September 2012 Yar Li Tan,1,2 Lakshmanasamudram S Mohanram,1 Seng Ei Ti,1,2 Tin Aung,1–3 Shamira Perera1,2 1Singapore National Eye Centre, 2Singapore Eye Research Institute, 3National University of Singapore, Yong Loo Lin School of Medicine, Buona Vista, Singapore Background: Anterior segment optical coherence tomography (ASOCT) was used to categorize and provide insights into the etiology of capsular bag distension syndrome (CBDS). Methods: A prospective review was undertaken of 10 cases who presented with signs of late CBDS 5–11 years after uneventful phacoemulsification with in-the-bag posterior chamber intraocular lens implantation. Results: All 10 patients presented with a milky collection within the distended capsular bag without raised intraocular pressure or a shallow anterior chamber. ASOCT was used to confirm the diagnosis in all cases, and a hyperintense signal was seen in the space between the posterior chamber intraocular lens and the posteriorly bowed posterior capsule. The continuous curvilinear capsulorhexis was measured to be between 3.18 mm and 4.70 mm. Three cases had uncorrected visual acuity better than 6/12. Uncomplicated Neodymium-doped Yttrium Aluminium Garnet (Nd:YAG) posterior capsulotomy was performed in eight patients, with no resulting change in the intraocular lens position (measured by ASOCT) or subjective refraction. Conclusion: Our study showed that ASOCT is a useful modality to differentiate this condition clearly from posterior chamber intraocular lens opacification and to investigate its causation. Nd:YAG posterior capsulotomy proved to be a safe and successful treatment for late CBDS with no change in biometric or refractive parameters.
Aplicaciones Clínicas de la tomografía de Coherencia óptica de Alta Resolución para el Estudio de Segmento Anterior
Dennis E Cortés,Brett L Shapiro,Eric K Chin,John S Werner
Vision Pan-America , 2013,
Abstract: Anterior segment optical coherence tomography (OCT) is an innovative technique that provides detailed images of internal structures in biological tissues with a noncontact, noninvasive, high resolution exam for evaluation of anterior segment and ocular surface.This article reviews the fundamentals and clinical applications of OCT, considering relevant information about advantages and limitations, describing its role in the diagnosis, surgical planning and clinical evaluation of patients with a variety of conditions from anterior segment. We included images of clinical cases evaluated at the department of cornea and external diseases at UC Davis Medical Center, using high resolution spectral-domain OCT (Heidelberg Engineering GmbH. Germany) for the study of the anterior segment.
Reproducibility of Corneal Graft Thickness measurements with COLGATE in patients who have undergone DSAEK (Descemet Stripping Automated Endothelial Keratoplasty)
Wong Melissa HY,Chew Annabel,Htoon Hla M,Lee Beng H
BMC Medical Imaging , 2012, DOI: 10.1186/1471-2342-12-25
Abstract: Background The CorneaL GrAft Thickness Evaluation (COLGATE) system was recently developed to facilitate the evaluation of corneal graft thickness from OCT images. Graft thickness measurement can be a surrogate indicator for detecting graft failure or success. The purpose of this study was to determine the reproducibility of the COLGATE system in measuring DSAEK graft area between two observers. Methods This was a prospective case series in which 50 anterior segment OCT images of patients who had undergone DSAEK in either eye were analysed. Two observers (MW, AC) independently obtained the image analysis for the graft area using both semi automated and automated method. One week later, each observer repeated the analysis for the same set of images. Bland-Altman analysis was performed to analyze inter and intra observer agreement. Results There was strong intraobserver correlation between the 2 semi automated readings obtained by both observers. (r = 0.936 and r = 0.962). Intraobserver ICC for observer 1 was 0.936 (95% CI 0.890 to 0.963) and 0.967 (95% CI 0.942 to 0.981) for observer 2. Likewise, there was also strong interobserver correlation (r = 0.913 and r = 0.969). The interobserver ICC for the first measurements was 0.911 (95% CI 0.849 to 0.949) and 0.968 (95% CI 0.945 to 0.982) for the second. There was statistical difference between the automatic and the semi automated readings for both observers (p = 0.006, p = 0.003). The automatic readings gave consistently higher values than the semi automated readings especially in thin grafts. Conclusion The analysis from the COLGATE programme can be reproducible between different observers. Care must be taken when interpreting the automated analysis as they tend to over estimate measurements.
Modificaciones del segmento anterior ocular posterior a iridotomía láser periférica mediante tomografía de coherencia óptica Modifications of posterior ocular anterior segment with peripheral laser iridotomy
Liamet Fernández Argones,Germán álvarez Cisneros,Ibraín Piloto Díaz,Francisco Fumero González
Revista Cubana de Investigaciones Biom??dicas , 2011,
Abstract: OBJETIVO: Evaluar los cambios a corto plazo en el segmento anterior ocular pos-iridotomía láser periférica, mediante tomografía de coherencia óptica de segmento anterior. MéTODOS: Estudio longitudinal prospectivo de serie de casos en 30 pacientes (46 ojos) con sospecha de cierre angular primario. Las imágenes fueron tomadas con el equipo SL-OCT Heidelberg Engineering en el preoperatorio y a los 7 días posoperatorios. Se evaluaron variables relacionadas con mensuraciones de las estructuras del segmento anterior. RESULTADOS: Las mensuraciones de cada cuadrante fueron similares en el preoperatorio mientras en el posoperatorio hubo diferencias significativas en todas las variables a expensas de los cuadrantes nasal e inferior, excepto para la distancia iris-espolón (p = 0,926) y distancia de apertura angular a 750 μm (p = 0,069). Los cambios posláser fueron significativos en todas las variables relacionadas con mensuraciones angulares (p = 0,000), volumen de cámara anterior (p = 0 000) y profundidad central de cámara anterior (p =0,011). La amplitud angular se incrementó como promedio en 8,7 ±,5,9 grados pos-láser y se correlacionó negativamente con las variables preoperatorias distancia iris-espolón (p =0,007), distancia de apertura angular a 500 μm (p = 0,031), área del espacio irido-trabecular a 500 μm (p = 0,003) y 750 μm (p =0,026). Al comparar los cambios pos-operatorios entre ojos adelfos las diferencias no fueron significativas. CONCLUSIóN: La iridotomía láser es efectiva en incrementar la amplitud angular, asociándose a incremento en el volumen y profundidad central de la cámara anterior en la sospecha de cierre angular primario. OBJECTIVE: To evaluate post-laser peripheral iridotomy variations of anterior ocular segment by anterior segment optical coherence tomography. METHOD: Prospective observational case series in 30 patients (46 eyes) diagnosed with primary angle- closure suspect. The tomography was obtained pre-operative and at seven days post-operative by SL-OCT Heidelberg Engineering. Quantitative variables related to anterior segment structures were analyzed before and after the laser peripheral iridotomy treatment. RESULTS: There were no pre-operative statistical differences between quadrants. In the pos-op period all variables showed significant differences particularly at inferior and nasal quadrant, except for iris-scleral spur distance (p=0.926) and angle opening distance at 750μm (p=0.069). Pos-laser changes were significant for variables related to the angle (p=0.000), anterior chamber volume (p=0.000), and anterior chamber depth (p
白内障超声乳化术后早期区域性角膜水肿的临床研究
刘振兴,周祁,陈冉冉,刘歆,陆卫海,毕燕龙
- , 2016, DOI: 10.16118/j.1008-0392.2016.01.009
Abstract: 目的 探讨白内障超声乳化术后早期区域性角膜水肿的临床特征。方法 收集行白内障超声乳化联合人工晶体植入术的患者50例(50只眼)。采用角膜内皮显微镜(corneal specular microscope, CSM)对手术前后角膜中央、12点、3点、6点及9点位的5个象限,每一象限的5个区域总共25个位置的角膜内皮细胞(corneal endothelial cells, CECs)进行拍照、图像合并及数字化分析。采用眼前节光学相干断层扫描仪(anterior segment optical coherence tomography, AS-OCT)获取白内障手术前后全角膜厚度图,分析区域性角膜水肿与区域性CECs密度(corneal endothelial cell density, CD)改变的相关性。结果 入组50例手术均顺利实施,随访期(12.5±1.1)个月。5个象限共25个位置CEC数据显示: 术后1d,平均CD为(2045±153)个/mm2,较术前平均(2557±265)个/mm2差异有统计学意义(P<0.01)。与中央区参数相比,12、3、6、9点位CD差异均存在统计学意义(P<0.01)。术后1d,在中央、12、6、9、3点位,角膜厚度变化分别为(162.7±84.8)、(285.1±114.5)、(121.1±91.2)、(257.2±123.4)、(145.1±91.4)μm,均较术前增加(P均<0.01)。术后1d,区域性CD减少与区域性角膜水肿存在正相关(r=0.87,P=0.001)。结论 白内障术后区域性的角膜厚度增加可间接反映区域性CD减少的程度。
Objective To study the clinical characteristics of early regional corneal edema after cataract phacoe mulsification. Methods Fifty patients (50 eyes), who underwent cataract phacoemulsification and IOL implantation, were enrolled in the study. The corneal specular microscope (GSM) was used to capture 25 photos of corneal endothelial cells at 5 regions located in cener of cornea, 12,3, 6, and 9 o'clock, the photos were then combined and analyzed with photoshop software. Anterior segment optical coherence tomography (AS-OCT) was used to capture the digital maps of the whole corneal thickness. Relationship of the regional corneal edema and corneal endothelial cells density (CD) changes were analysed. Results All the surgeries 50 cases were perform successfully, the follow up period was(12.5±1.1) months. The average CDs based on the 25 photos of each cornea were (2557±265) cells/mm2 before surgery and(2045±153) cells/mm2 1 day after surgery (P<0.01). Compared to the central CD, CDs in the 12,3, 6,9 O'clock showed significant differences (all P<0.01). Compared to the corneal thickness before surgery, the thickness changes at d1 after surgery in the center of cornea, 12,6, 9 and 3 o'clock were (162.7±84.8),(285.1±114.5),(121.1±91.2),(257.2±123.4), (145.1±91.4)μm respectively (P <0.01). The regional CD was correlated with regional corneal thickness changes (r = 0.87, P=0.001). Conclusion The increasing of regional corneal thickness can reflect the degree of regional CD decreasing after cataract phacoemuls-ification
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