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Macular thickness measured by optical coherence tomography in a healthy population before and after uncomplicated cataract phacoemulsification surgery
No full textPURPOSE:
To examine macular changes before and after uncomplicated cataract surgery in a healthy population.
MATERIAL AND METHODS:
In a prospective study, we evaluated 62 eyes of healthy patients having elective cataract phacoemulsification. We performed optical coherence tomography (OCT) measurements preoperatively and at 3, 6, 12, 20, and 28 weeks after surgery. The retinal map was divided into minimal foveal thickness, a central 1-mm disk area, and two peripheral ring areas with diameters of 3 mm and 6 mm, respectively, and centered on the fovea. We compared the postoperative OCT values against the respective preoperative values.
RESULTS:
Two eyes (3.2%) developed cystoid macular edema (CME) after cataract surgery and were excluded from the study. With respect to preoperative values, visual acuity improved significantly postoperatively, and at 12 weeks, we observed an asymptomatic increase in retinal thickness at 3 mm and 6 mm. Macular volume showed a statistically significant increase at the 12th week after surgery. There was no correlation between macular changes and best corrected visual acuity (BCVA) or ultrasound time.
CONCLUSIONS:
Our data indicate that the onset of clinically significant CME is rare after uncomplicated phacoemulsification cataract surgery, but with respect to preoperative values we observed an asymptomatic increase in macular thickness and volume at 12 weeks. The possible onset of macular alterations after uncomplicated cataract surgery must be taken into account as a potential later complication, because it can lead to a permanent loss of visual acuity
Automated Quantitative Analysis of Retinal Microvasculature in Normal Eyes on Optical Coherence Tomography Angiography
No full textPurpose To describe a new automated quantitative technique for displaying and analyzing macular vascular perfusion using optical coherence tomography angiography (OCT-A) and to determine a normative data set, which might be used as reference in identifying progressive changes due to different retinal vascular diseases. Design Reliability study. Methods A retrospective review of 47 eyes of 47 consecutive healthy subjects imaged with a spectral-domain OCT-A device was performed in a single institution. Full-spectrum amplitude-decorrelation angiography generated OCT angiograms of the retinal superficial and deep capillary plexuses. A fully automated custom-built software was used to provide quantitative data on the foveal avascular zone (FAZ) features and the total vascular and avascular surfaces. A comparative analysis between central macular thickness (and volume) and FAZ metrics was performed. Repeatability and reproducibility were also assessed in order to establish the feasibility and reliability of the method. Results The comparative analysis between the superficial capillary plexus and the deep capillary plexus revealed a statistically significant difference (P < .05) in terms of FAZ perimeter, surface, and major axis and a not statistically significant difference (P > .05) when considering total vascular and avascular surfaces. A linear correlation was demonstrated between central macular thickness (and volume) and the FAZ surface. Coefficients of repeatability and reproducibility were less than 0.4, thus demonstrating high intraobserver repeatability and interobserver reproducibility for all the examined data. Conclusions A quantitative approach on retinal vascular perfusion, which is visible on Spectralis OCT angiography, may offer an objective and reliable method for monitoring disease progression in several retinal vascular diseases
Outer Retinal and Choroidal Evaluation in Multiple Evanescent White Dot Syndrome (MEWDS): An Enhanced Depth Imaging Optical Coherence Tomography Study
No full textPurpose: To perform an analysis of optical coherence tomography (OCT) abnormalities in patients with MEWDS, during the acute and recovery stages, using enhanced depth imaging-OCT (EDI-OCT). Methods: A retrospective case series of five patients with MEWDS was included. EDI-OCT imaging was evaluated to detect retinal and choroidal features. Results: In the acute phase, focal impairment of the ellipsoid zone and external limiting membrane, hyperreflective dots in the inner choroid, and full-thickness increase of the choroidal profile were observed in the affected eye; disappearance of these findings and restoration of the choroidal thickness (p = 0.046) was appreciated in the recovery phase. No OCT abnormalities were assessed in the unaffected eye. Conclusions: EDI-OCT revealed transient outer retinal layer changes and inner choroidal hyperreflective dots. A transient increased thickness of the whole choroid was also identified. This might confirm a short-lasting inflammatory involvement of the whole choroidal tissue in the active phase of MEWDS
Full-thickness choroidal thinning as a feature of Fuchs Uveitis Syndrome: quantitative evaluation of the choroid by Enhanced Depth Imaging Optical Coherence Tomography in a cohort of consecutive patients
No full textPurpose: To perform a quantitative analysis of choroidal thickness in patients with Fuchs Uveitis Syndrome (FUS) using enhanced depth imaging optical coherence tomography (EDI-OCT). Methods: All patients underwent comprehensive ophthalmic examination, including best-corrected visual acuity, slit-lamp biomicroscopy, applanation tonometry, axial length measurements with a swept-source biometer (IOLMaster 700, Carl Zeiss Medic AG, Jena, Germany) and macular 30° linear EDI- B-scan SD-OCT section (Spectralis HRAII+OCT, Heidelberg Engineering, Heidelberg, Germany) in both eyes. Analysis of choroidal thickness was performed at three different locations: subfoveally, 750 μm nasally, and 750 μm temporally to the fovea. Patients having received any surgery or intravitreal injections in the last 12 months and with axial length variance ≥ 1 mm between both eyes were excluded. Results: Sixteen eyes of eight consecutive patients with unilateral FUS were included. Segmented analysis of the choroid, separately considering Haller’s layer and Sattler’s–choriocapillaris layers, showed statistically significant lower values (p < 0.05) in affected eyes (FEs) compared to fellow eyes (NFEs). In NFEs, total choroidal thickness mean values ranged from 305.62 ± 92.96 μm to 347.50 ± 91.55 μm; in FEs those values were significantly lower (p < 0.05), ranging from 232.62 ± 89.33 μm to 255.62 ± 89.33 μm. Conclusion: Diffuse and full-thickness choroidal thinning in FEs was observed. Considering the absence of significant axial length differences between FEs and NFEs in our patient series, these data seem to suggest that the full-thickness choroidal thinning in FEs may be due to the inflammatory process. In that way, FUS might be regarded as an inflammatory condition involving the whole uveal tunic, even the posterior part of it, definitively supplanting the early definition of “heterochromic iridociclytis”
New Insights On Ocular Sarcoidosis: An Optical Coherence Tomography Angiography Study
No full textPurpose: To report optical coherence tomography angiography (OCT-A) findings in eyes with ocular sarcoidosis (OS) and to compare these findings with those of fluorescein angiography (FA). Methods: Observational, cross-sectional, case-control study. Patients presenting with OS involving the posterior segment were evaluated using FA, structural-OCT and OCT-A. OCT-angiograms of the superficial (SCP) and deep (DCP) capillary plexuses and choriocapillaris (CC) were qualitatively and quantitatively analyzed. Results: OCT-A seemed more sensitive than FA in detecting perifoveal capillary arcade disruptions, areas of hypoperfusion/non-perfusion and capillary abnormalities (p<0.05). Capillary hypoperfusion was more frequently detected in the DCP than in SCP, conversely capillary abnormalities were more often observed at the level of the SCP. Capillary vessel density values were significantly lower in eyes with OS than in healthy controls both at the level of DCP and CC (p<0.05). Conclusion: The depth-resolved nature of OCT-A allowed new insights on OS-induced microvascular and perfusion impairments
Posterior corneal surface stability after femtosecond laser-assisted keratomileusis
Full text linkThe purpose of this study was to evaluate posterior corneal surface variation after femtosecond laser-assisted keratomileusis in patients with myopia and myopic astigmatism. Patients were evaluated by corneal tomography preoperatively and at 1, 6, and 12 months. We analyzed changes in the posterior corneal curvature, posterior corneal elevation, and anterior chamber depth. Moreover, we explored correlation between corneal ablation depth, residual corneal thickness, percentage of ablated corneal tissue, and preoperative corneal thickness. During follow-up, the posterior corneal surface did not have a significant forward corneal shift: no significant linear relationships emerged between the anterior displacement of the posterior corneal surface and corneal ablation depth, residual corneal thickness, or percentage of ablated corneal tissue
Predictive value for cerebrospinal fluid Alzheimer's disease profile of different measures of verbal episodic memory in patients with MCI
No full text: Neuropsychological evidence of memory impairment represents the main feature of the clinical onset of typical Alzheimer's disease (AD). Rey's Auditory Verbal Learning Test (RAVLT) and Logical Memory (LM) are two tests both assessing verbal episodic memory, widely used in clinical practice. Our aim was to investigate the added value of their combined use in predicting cerebrospinal fluid (CSF) AD biomarkers positivity in a retrospective consecutive series of patients with mild cognitive impairment (MCI). 169 MCI patients were included. For all of them neuropsychological assessment and CSF analysis were available. According to CSF A/T/(N) profile, 109 were defined as MCI due to AD (A+T+), and 60 were non-AD MCI (A-T-). Logistic regression model and receiver-operating characteristic (ROC) curves were analyzed to evaluate the discriminatory power of single and combined sub-measures between AD and non-AD patients. The combination of RAVLT-del with LM could acceptably discriminate the two groups (AUC: 0.69, CI 95% 0.617-0.761, sens: 0.75, spec. 0.58, p < 0.001), while the single tests did not show sufficient discriminative performance. Our study shows that the combination of RAVLT delayed recall with LM better predicts the biological AD diagnosis (A+T+), showing a good discriminative power between MCI-AD from non-AD MCI. Since RAVLT and LM assess different components of verbal episodic memory, they should be considered as complementary, rather than interchangeable, tests
Retinal Microvasculature in Nonproliferative Diabetic Retinopathy: Automated Quantitative Optical Coherence Tomography Angiography Assessment
No full text<b><i>Purpose:</i></b> To perform a qualitative and quantitative assessment of the foveal microvasculature in eyes with diabetic maculopathy using optical coherence tomography angiography (OCT-A). <b><i>Methods:</i></b> Retrospective case series of 48 eyes with diabetic maculopathy and 47 healthy eyes evaluated by Spectralis OCT-A. Perifoveal arcade disruptions, linear vascular dilations, microaneurysms, intraretinal microvascular abnormalities and flow-void areas were qualitatively analyzed on OCT angiograms both for the superficial (SCP) and deep (DCP) capillary plexuses. A fully automated microstructural analysis of the foveal avascular zone (FAZ) metrics, vascular and avascular surfaces was performed. Quantitative values from diabetic patients were compared with those of healthy subjects. <b><i>Results:</i></b> A moderate agreement between SCP and DCP in terms of diabetes-induced vascular lesions in the qualitative assessment was shown. The comparative quantitative analysis between SCP and DCP in diabetic patients revealed a statistically significant difference (<i>p</i> < 0.05) in terms of FAZ perimeter and FAZ surface. No statistically significant difference was shown in total vascular and avascular surfaces. A statistically significant difference between the diabetic and control groups was noticed both for SCP and DCP considering FAZ metrics and vascular surfaces. <b><i>Conclusions:</i></b> A qualitative and quantitative OCT-A approach on retinal vascular perfusion may offer an objective and reliable method for monitoring disease progression in diabetic retinopathy.</jats:p
Repeatability of Retinal Macular Thickness Measurements in Healthy Subjects and Diabetic Patients with Clinically Significant Macular Edema: Evaluation of the Follow-Up System of Spectralis Optical Coherence Tomography
No full textBackground: It was the aim of this study to compare the repeatability of Spectralis optical coherence tomography (OCT) retinal thickness measurements in healthy subjects and diabetic patients with clinically significant macular edema (CSME) with or without the use of the follow-up system. Methods: Thirty-eight eyes of 38 healthy subjects (control group) and 68 eyes of 68 diabetic patients with CSME were included in the study. The coefficient of repeatability (CR) and intrasession coefficients of variation were tested with 20 x 15 degree raster scans consisting of 19 high-resolution line scans (15 frames per scan) that were repeated 3 times by 1 experienced examiner.The first scan was set as the reference scan, whereas the second and third scans were the follow-up scans and were performed with and without the use of the follow-up mode, respectively. Results: The means and standard deviations for the central foveal subfield (CSF) in healthy subjects and diabetic patients were 289 +/- 21 and 402 +/- 105 mu m, respectively. Particularly in diabetic patients, examining the CSF, CR was 2.67% (10.73 mu m) and 6.73% (27.01 mu m) with and without using the follow-up mode, respectively, and the difference was statistically significant (p < 0.05). Conclusion: These results support the hypothesis that the follow-up system improves the repeatability either in healthy subjects or in diabetic patients with poor fixation. The wider improvement in repeatability in diabetic patients in the follow-up system group compared to the no follow-up system group are probably related to poor patient fixation or eye movement in patients with CSME. (C) 2015 S. Karger AG, Base
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