Cube Volume Research Articles

Dry Age-Related Macular Degeneration – A New Approach In Optical Coherence Tomography Monitoring And Quantitative Assessment

Summary The purpose of the study was to present the ability of Drusen analysis software tool to measure drusen area and volume in patients with dry age-related macular degeneration (AMD). Eleven patients with confirmed dry AMD aged 59-74 years were scanned with 3D OCT-2000 Topcon 3D Macula scanning protocol by a single operator. All subjects underwent a complete ophthalmologic examination including best corrected visual acuity, indirect biomicroscopy, tonometry, fluorescein angiography and OCT. Drusen analysis was performed on the macula with 6.0 × 6.0 mm volume cube scans and 512×128 pixels scan resolution. The results were presented along with calculated values in two clearly arranged reports. Mean follow-up period was 19 months (6-40). Count, area occupation, volume of the drusen and 3D retinal pigment epithelium (RPE) elevation map were presented in a Macula drusen analysis report. Drusen count and volume in 6 patients were increased at the end of follow-up period. There were 5 patients with regression in drusen count and area and volume of the drusen in 3 of them were higher than on previous examination. Another 2 were with regression not only in drusen count but also in their area and volume. With this software tool the status of RPE can be objectively and automatically examined in detail and can be followed up over time. OCT allows for precise quantitative evaluation and study of microstructural changes in patients with dry AMD and provides three-dimensional information of macular pathology in situ and in real time. This could be useful for determining stages and monitoring the progression of AMD.

Outer Retinal Tubulation in the Comparison of Age-Related Macular Degeneration Treatments Trials (CATT)

To determine the prevalence of, risk factors for, and visual acuity (VA) correlations with outer retinal tubulation (ORT) seen on spectral-domain optical coherence tomography (SD OCT) in eyes with neovascular age-related macular degeneration (AMD) after anti-vascular endothelial growth factor (VEGF) therapy. Prospective cohort study within a randomized clinical trial. Patients with SD OCT images at weeks 56 and 104 in the Comparison of AMD Treatments Trials (CATT). Participants in the CATT were assigned randomly to ranibizumab (0.5 mg) or bevacizumab (1.25 mg) treatment and to a monthly or pro re nata (PRN) injection-dosing regimen. A subset of eyes was imaged with SD OCT beginning at week 56. Cirrus 512×128 or Spectralis 20°×20° volume cube scan protocols were used to acquire SD OCT images. Two independent readers at the CATT OCT reading center graded scans, and a senior reader arbitrated discrepant grades. The prevalence of ORT, identified as tubular structures seen on at least 3 consecutive Cirrus B scans or 2 consecutive Spectralis B scans, was determined. The associations of patient-specific and ocular features at baseline and follow-up with ORT were evaluated by univariate and multivariate analyses. Outer retinal tubulations. Seven of 69 eyes (10.1%) at 56 weeks and 64 of 368 eyes (17.4%) at week 104 had ORTs. Absence of diabetes, poor VA, blocked fluorescence, geographic atrophy, greater lesion size, and presence of subretinal hyperreflective material at baseline were associated independently with greater risk of ORT at 104 weeks (P < 0.05). Neither drug nor dosing regimen were associated significantly with ORT. The mean VA of eyes with ORT at week 104 (58.5 Early Treatment Diabetic Retinopathy Study letters) was worse than the mean VA of eyes without ORT (68.8 letters; P < 0.0001). At 2 years after initiation of anti-VEGF therapy for neovascular AMD, ORTs are present in a substantial proportion of eyes. We identified baseline features that independently predict ORTs. It is important to identify ORTs because eyes with ORTs have worse VA outcomes than those without this finding.

Prospective Retinal and Optic Nerve Vitrectomy Evaluation (PROVE) Study: Twelve-Month Findings

To report 1-year outcomes of the Prospective Retinal and Optic Nerve Vitrectomy Evaluation study. Prospective, controlled, observational study. Eighty eyes of 40 participants undergoing pars plana vitrectomy for epiretinal membrane (ERM), macular hole (MH), or vitreous opacities. Enrolled participants underwent baseline evaluation of the study (surgical) and fellow (control) eyes by a masked fellowship-trained glaucoma specialist; evaluation included intraocular pressure (IOP; Goldmann applanation and Tono-Pen), central corneal thickness, gonioscopy, and cup-to-disc ratio measurement. Baseline testing included bilateral color fundus and optic disc photography, fundus autofluorescence, automated perimetry, and optical coherence tomography (OCT) of the macula and optic nerve. Evaluations were repeated at 3 months and 1 year after surgery. The primary outcome measure was changes in peripapillary retinal nerve fiber layer (pRNFL) thickness. Secondary outcomes included changes in macular thickness and IOP. Thirty-eight of 40 patients completed 1 year of follow-up. Mean visual acuity (VA) improved in study eyes from baseline (P = 0.003) but remained worse than fellow eyes (P<0.001). Study eyes had thinner inferior pRNFL thickness (114±16.8 μm) compared with fellow eyes (123±14.7 μm; P = 0.004). Mean IOP difference between study eyes and fellow eyes increased from baseline to 1 year. At 1 year, MH study eyes had higher mean IOP (16.0±3.7 mmHg) compared with fellow eyes (14.8±3.4 mmHg; P = 0.08). Mean IOP for pseudophakic study eyes increased from 14.5±3.2 mmHg at baseline to 16.0±2.8 mmHg at 1 year (P = 0.04). Central subfield thickness (CST) and cube volume decreased in study eyes at 1 year but remained greater than that of fellow eyes (P<0.05). Reduction in CST from baseline correlated with degree of VA improvement (P<0.05). Mean deviation (MD) improved in ERM study eyes at 1 year when compared with baseline (-2.2 vs. -4.0; P = 0.02) but remained worse than fellow eyes (-1.2; P = 0.002). One year after vitrectomy, VA, CST, and MD improved in study eyes but not to the level of fellow eyes. Inferior pRNFL thickness decreased in study eyes. Reduction in CST from baseline correlated with degree of VA improvement. Pseudophakic study eyes demonstrated increased IOP when compared with baseline.

Glaucoma diagnostic value of the total macular thickness and ganglion cell-inner plexiform layer thickness according to optic disc area

AimsThis study examined the diagnostic value of the perimacular ganglion cell-inner plexiform layer (GCIPL) thickness in the detection of glaucoma according to the optic disc area.MethodsThe participants underwent reliable standard...

Determinants of Macular Thickness Using Spectral Domain Optical Coherence Tomography in Healthy Eyes: The Singapore Chinese Eye Study

We determined ocular and systemic factors influencing macular thickness measured by spectral-domain optical coherence tomography (SD-OCT) in a population-based sample of healthy eyes. We recruited 490 healthy Chinese adults, aged 40 to 80 years, from the Singapore Chinese Eye Study, a population-based survey. All participants underwent a comprehensive eye examination and a standardized interview. The SD-OCT (Cirrus HD-OCT, software version 6.0) was used to measure a range of macular thickness parameters (central foveal subfield thickness, average inner macular thickness, average outer macular thickness, overall average macular thickness, and overall macular cube volume). Linear regression analyses were performed to examine the effects of various ocular and systemic factors on macular thickness. The mean (standard deviation) age of the subjects was 53.17 (6.14) years and 50.0% of them were male. The mean central foveal subfield, average inner, and average outer macular thicknesses were 250.38 (20.58), 319.33 (14.40), and 276.67 (11.94) μm, respectively. The overall average macular thickness was 280.25 (11.42) μm and overall macular cube volume was 10.09 (0.41) mm(3). Sex, age, and axial length (AL) are the factors that influenced macular thicknesses. Thinner overall average macular thickness was associated with female sex (4.46 μm thinner compared to males, P < 0.001), older age (0.38 μm decrease per each year increase in age, P < 0.001), and longer AL (2.34-μm decrease per each mm increase in AL, P < 0.001), whereas thinner central foveal subfield thickness was associated with female sex (13.5 μm thinner compared to males, P < 0.001) and shorter AL (3.33-μm decrease per each mm increase in AL, P < 0.001). Female sex, older age, and longer AL were associated independently with thinner overall average macular thickness, whereas female sex and shorter AL were associated with thinner central foveal thickness in ethnic Chinese. These factors should be taken into consideration when interpreting macular thickness measurements with SD-OCT.

Short-Term Outcomes of Aflibercept for Neovascular Age-Related Macular Degeneration in Eyes Previously Treated With Other Vascular Endothelial Growth Factor Inhibitors

To report results of aflibercept therapy in eyeswith neovascular age-related macular degeneration previously treated with bevacizumab, ranibizumab, or both. Retrospective, interventional, noncomparative, consecutive case series. Ninety-six eyes from 85 patients with neovascular age-related macular degeneration who previously had received bevacizumab, ranibizumab, or both were treated with aflibercept monthly for 3months followed by a fourth injection within 2months. Outcomes were determined 4 ± 1months after the first aflibercept dose and included: proportion of patients gaining or losing 2 lines or more of best-corrected visual acuity, proportion remaining within a gain or loss of 1 line, mean change in logarithm of the minimal angle of resolution visual acuity, mean change in central foveal thickness, mean change in macular cube volume, and qualitative anatomic response as assessed by spectral-domain optical coherence tomography. At baseline, 82 (85%) eyes had signs of active exudation despite a mean of 17 previous anti-vascular endothelial growth factor injections. At final visit, 82 (85%) remained stable within a gain or loss of 1 line, 7 (7%) gained 2 lines or more, and 7 (7%) lost 2 lines or more of best-corrected visual acuity. Mean logarithm of the minimal angle of resolution visual acuity showed minimal change 0.02 (range,-0.46 to 0.70; P= .14). Mean central foveal thickness decreased-18μm (range,-242 to 198μm; P= .06). Mean macular volume decreased-0.27mm(3) (95% confidence interval,-0.4 to-0.1mm(3); P= .004). On qualitative analysis, 4 (5%) eyes had complete resolution of exudative fluid, 40 (49%) showed partial resolution, 26 (32%) remained unchanged, and 12 (14%) showed worsened exudative fluid. Aflibercept seems to be an effective alternative for neovascular age-related macular degeneration patients previously treated with bevacizumab, ranibizumab, or both at 4months of follow-up. Most treated eyes demonstrated stable visual acuity and anatomic improvements by spectral-domain optical coherence tomography.

EARLY TREATMENT RESPONSE OF FLUOCINOLONE (RETISERT) IMPLANTATION IN PATIENTS WITH UVEITIC MACULAR EDEMA

To analyze the early spectral domain optical coherence tomography changes after fluocinolone implantation in eyes with baseline uveitic macular edema. Patients with uveitic macular edema and who received fluocinolone implantations by 2 surgeons (R.P.S. and J.E.S.) at the Cole Eye Institute (Cleveland Clinic, Cleveland, OH) from September 2009 to July 2010 were eligible for this study. Best-corrected visual acuity, intraocular pressure, central subfield thickness, cube volume, cube average thickness, and cystoid macular edema grade were recorded before implantation and in the early postoperative period (median: 3 months postimplantation). Changes in these variables were analyzed using the Wilcoxon signed-rank test for paired comparisons of clustered data. P values were 2 sided, and alpha was set at 0.05. Twelve eyes of seven patients were included in the study. The median best-corrected visual acuity improved in the early postoperative period after implantation (20/80 before implantation and 20/50 after implantation), but this improvement was not found to be significant (P = 0.12). However, the spectral domain optical coherence tomography measurements-central subfield thickness, cube volume, cube average thickness, and cystoid macular edema grade-were all significantly reduced (median changes: -234 μm [P = 0.02], -1 mm [P = 0.04], -39 μm [P = 0.04], and -3 [P = 0.03], respectively). Fluocinolone implantation is associated with a significant reduction in macular edema as measured by spectral domain optical coherence tomography in the early postoperative period, a result that is consistent with the proposed mechanism of the drug.

Detection of Glaucomatous Progression by Spectral-Domain Optical Coherence Tomography

To compare the rate of change of circumpapillary retinal nerve fiber layer (cRNFL) thickness, macular volume and thickness, and optic nerve head (ONH) parameters assessed using spectral-domain optical coherence tomography (SD-OCT) between eyes with progressing and nonprogressing glaucoma. Longitudinal, observational study. Two hundred seventy-nine eyes from 162 glaucoma patients followed for an average of 2.2 years. Eyes were classified as progressors and nonprogressors according to assessment of optic disc and RNFL photographs and visual field progression analysis. Linear mixed effects models were used to evaluate the overall rate of change of cRNFL thickness, macular volume and thickness, and ONH parameters after adjustment for age, spherical equivalent, signal strength, and baseline SD-OCT measurements. The rate of change of cRNFL thickness, macular volume, and thickness and ONH parameters. Sixty-three eyes (22.6%) from 52 subjects were identified as progressors. Average, inferior quadrant, and 6- and 7-o'clock sector cRNFL thickness decreased faster in progressors than in nonprogressors (-1.26 vs -0.94, -2.47 vs -1.75, -3.60 vs -2.52, and -2.77 vs -1.51 μm/year, respectively; all P<0.05). The ONH rim area decreased faster, and average and vertical cup-to-disc ratio increased faster in progressors than in nonprogressors (-0.016 vs -0.006 mm(2)/year, and 0.004 vs 0.002 and 0.006 vs 0.004 per year, respectively; all P<0.05). Macular cube volume and the thickness of temporal outer and inferior inner macular sectors decreased faster in progressors than in nonprogressors (-0.068 vs -0.048 mm(3)/year, and -2.27 vs -1.67 and -2.51 vs -1.73 μm/year, respectively; all P<0.05). Serial measurement of parameters in all 3 areas (cRNFL, macula, and ONH) by SD-OCT may permit identification of progression in glaucomatous eyes. The authors have no proprietary or commercial interest in any of the materials discussed in this article.

Evaluation of Peripapillary Retinal Nerve Fiber Layer Thickness in Patients With Vitamin B12 Deficiency Using Spectral Domain Optical Coherence Tomography

Purpose: To compare peripapillary retinal nerve fiber layer (RNFL) thicknesses measured by Cirrus HD optical coherence tomography (OCT) of patients with vitamin B12 deficiency with healthy controls and to evaluate the correlation between the peripapillary RNFL thickness and plasma vitamin B12 levels.Materials and Methods: Forty-five patients (19 male and 26 female) with a diagnosis of vitamin B12 deficiency (patient group) and 45 age- and sex- matched healthy subjects (control group) were consecutively enrolled in this study. Average, temporal, nasal, inferior, and superior quadrant peripapillary RNFL thicknesses of each subject were obtained using the Cirrus HD OCT. Disc area (DA) and rim area (RA), central subfield thickness (CST), cube volume (CV), and cube average thickness (CAT) were also measured.Results: Mean age of each group was 33.1 ± 6.5 years (range: 21–45 years). Mean plasma vitamin B12 level was 114.8 ± 34.0 pg/mL in the patient group and was 405.1 ± 20.0 pg/mL in the control group (p < 0.001). The patient and control groups were similar regarding axial length, plasma folate levels, DA, RA, CST, CV, CAT, and RNFL thicknesses in superior, nasal, and inferior quadrants. However, average RNFL and RNFL in temporal quadrant were significantly thinner in the patient group than in the control group (p = 0.013 and p < 0.001, respectively). In addition, temporal (r = 0.356, p = 0.001) and average (r = 0.212, p = 0.045) peripapillary RNFL thicknesses were correlated with plasma vitamin B12 levels.Conclusion: We have shown that, as in other non-glaucomatous optic neuropathies, temporal quadrant RNFL thickness was thinner in patients with vitamin B12 deficiency and it was correlated with plasma vitamin B12 levels. Further studies are warranted to clarify the clinical relevance of these findings and the effects of vitamin B12 replacement therapy.

Relevant sampling of band-limited functions

We study the random sampling of band-limited functions of several variables. If a band-limited function with bandwidth has its essential support on a cube of volume $R^{d}$, then $\mathcal{O}(R^{d}\log R^{d})$ random samples suffice to approximate the function up to a given error with high probability.

Effect of multizone refractive multifocal contact lenses on the Cirrus HD OCT retinal measurements

BackgroundSimultaneous vision multifocal contact lenses are widely used to alleviate the symptoms of presbyopia. These contact lenses create simultaneous retinal images due to the incoming light distribution being divided into two or more focuses. Our aim was to evaluate whether the multizone refractive multifocal contact lenses affect the measurements of the retinal nerve fibre layer (RNFL) and macular thickness using optical coherence tomography (OCT).MethodsIn this cross‐over study, 30 eyes of 30 subjects with a mean age of 50.42 ± 7.82-years were fitted with multizone refractive multifocal contact lenses. Using the Thickness Analysis mode of the Cirrus HD (Carl Zeiss, Meditec, Dublin, CA, USA) OCT, the average, superior, nasal, inferior, temporal and 12 o'clock‐hour retinal nerve fibre layer thicknesses were obtained. In Macular Thickness Analysis mode of Cirrus HD OCT, the average cube thickness, macular cube volume, central subfield thickness, inner and outer macular thickness (superior, inferior, nasal and temporal area) were obtained. Measurements were performed with and without contact lenses.ResultsStatistically significant differences were not found in RNFL thickness at any of the studied areas and for 12 o'clock‐hour sectors analysed (p > 0.07). The mean macular volume was 9.86 ± 0.30 mm3 and 9.87 ± 0.27 mm3 with and without multifocal contact lenses, respectively (p = 0.38). There were no statistically significant differences in average macular thickness or macular thickness of areas analysed between the measurements with and without multifocal contact lenses (p > 0.09). The signal strength was higher than seven for all scans, and differences were not found in the mean of signal strength between the measurements with and without contact lenses.ConclusionsThe results of this study suggest that the assessed multizone refractive multifocal contact lens does not affect the retinal nerve fibre layer and macular thickness measurements using Cirrus HD OCT.

Evaluation of the retinal changes in patients with chronic migraine

The aim of this study was to investigate retinal nerve fiber layer (RNFL) thickness and macular changes (central subfield thickness, cube average thickness, cube volume) in patients with chronic migraine (CM) without visual impairment using spectral-domain optical coherence tomography (SD-OCT) and to compare the results to healthy controls. A total of 80 subjects, including 40 CM patients (24 females, 16 males, [corrected] at 19-36 years of age) with no migraine prophylactic treatment and 40 healthy controls (22 females, 18 males, [corrected] at 20-40 years of age) were enrolled. Both eyes of patients with CM and controls were imaged using Cirrus HD SD-OCT (Carl Zeiss Meditec, Dublin, CA, USA). The average RNFL thickness was not significantly thinner in patients with CM. The mean average RNFL thickness was 83 ± 10.5 μm in CM patients and 85 ± 9.6 μm in healthy controls (p = 0.648), but superior quadrant RNFL thickness in the CM patients was significantly lower than healthy controls. The mean superior RNFL thickness was 86 ± 6.7 μm in CM patients and 108 ± 7.3 μm in controls (p < 0.001). Illness duration and frequency of the attacks were not affected by RNFL thickness. No significant differences were detected in macular changes between CM patients and healthy controls. In our study, the thickness of superior RNFL was found to be thinner in CM patients. This implies that longitudinal follow-up is needed to clarify whether RNFL thinning, in migraine patients, is related to a progressive loss of axons and retinal ganglion cells.

Salient material properties and haptic volume perception: The influences of surface texture, thermal conductivity, and compliance

We investigated the influences of surface texture, thermal conductivity, and compliance on the haptic perception of the volume of small cubes. It was hypothesized that an object containing highly salient material properties would be perceived as larger in volume than the same object without these properties. Blindfolded subjects were asked to explore pairs of cubes differing in their material properties and to select the one with the larger volume. The results showed that, counterintuitively, a smooth cube was perceived as being significantly larger than a rough cube of the same physical volume, with average biases of about 19%. Furthermore, cubes with a higher thermal conductivity were perceived as significantly larger than cubes with a lower thermal conductivity (average bias of about 7%). In addition, the magnitude of the bias in this condition was not changed by increasing or decreasing the temperature of the test objects, suggesting that the effect of thermal conductivity could not be attributed directly to the heat flow. Finally, a hard cube was perceived as significantly larger than a soft cube of equal physical volume, with an average bias of about 25%. These results reveal that the studied material properties have significant and consistent influences on the haptic perception of volume. The observed biases provide an indication of the levels at which the processing of haptic information on volume and material properties occurs.

The journey of QSO haloes from z ∼ 6 to the present

We apply a recently developed scaling technique to the Millennium-XXL, one of the largest cosmological N-body simulations carried out to date 3x10^11 particles within a cube of volume ~70Gpc^3). This allows us to investigate the cosmological parameter dependence of the mass and evolution of haloes in the extreme high-mass tail of the z=6 distribution. We assume these objects to be likely hosts for the population of rare but ultraluminous high-redshift quasars discovered by the Sloan Digital Sky Survey. Haloes with a similar abundance to these quasars have a median mass of 9x10^12 Msun in the currently preferred cosmology, but do not evolve into equally extreme objects at z=0. Rather, their descendants span the full range conventionally assigned to present-day clusters, 6x10^13 to 2.5x10^15 Msun for this same cosmology. The masses both at z=6 and at z=0 shift up or down by factors exceeding two if cosmological parameters are pushed to the boundaries of the range discussed in published interpretations of data from the WMAP satellite. The main factor determining the future growth of a high-mass z=6 halo is the mean overdensity of its environment on scales of 7 to 14 Mpc, and descendant masses can be predicted 6 to 8 times more accurately if this density is known than if it is not. All these features are not unique to extreme high-z haloes, but are generic to hierarchical growth. Finally, we find that extreme haloes at z=6 typically acquired about half of their total mass in the preceding 100 Myr, implying very large recent accretion rates which may be related to the large black hole masses and high luminosities of the SDSS quasars.

Effect of Angle of Incidence on Macular Thickness and Volume Measurements Obtained by Spectral-Domain Optical Coherence Tomography

Evaluation of the effect of angle of incidence on macular thickness and volume measurements obtained by spectral-domain optical coherence tomography (OCT). A total of 30 eyes from 15 healthy young subjects underwent macular cube volume scans (512 × 128 protocol) following dilation using the Cirrus spectral domain OCT. For each eye, scans were obtained by positioning the scanning beam in the center of the dilated pupil, as well as in four eccentric positions (approximately 3 mm from the center), superior, inferior, nasal, and temporal to the pupillary center, to create oblique angles of incidence between the light beam and retina. In all cases, the region scanned by the volume cube was centered on the fovea. Macular thickness and volume measurements were computed for volume scan acquisitions, and differences in values between eccentric scans and the central scan were analyzed. Retinal thickness and volume values were observed to increase significantly in all subfields for all eccentrically-obtained scans compared to scans obtained through the center of the pupil. The mean increase in thickness for the various scan positions and subfields ranged from 3.76 to 11.38. Scans that were displaced temporally consistently showed the greatest increase in thickness and volume, whereas nasally positioned scans showed the least increase. The increase in retinal thickness for all subfields correlated significantly with angle of inclination or tilting of the retina. Macular thickness and volume measurement results may be affected significantly by positioning of the scanning beam in the pupil and resultant angle of incidence on the retina. These findings suggest that care should be taken to position the scanning beam consistently in the center of the pupil to achieve reliable measurements.

Changes in macular thickness measurements repeatability with age using Cirrus Fourier‐domain optical coherence

AbstractPurpose To test the intrassession reproducibility of retinal thickness measurements using Cirrus Fourier‐domain optical coherence tomography (OCT). To evaluate if there is any relation between macular measurements repeatability and age of the studied subject.Methods Two hundred and nine of 209 healthy subjects underwent three macular 512x128 volume cube centered on the fovea done by the same experienced examiner using Cirrus HD OCT (Carl Zeiss, USA). Descriptive statistics, analysis of variance, intraclass correlation coefficients (ICC), and coefficients of variation (COV) were calculated for the 9 macular areas described by the Early Treatment Diabetic Retinopathy Study (ETDRS) in the macular protocol. Values were analysed related to other subject factors like age and VA.Results All measurements were highly reproducible. The ICCs ranged from 0.823 to 0.992 using macular volume cube. Mean COV was 1.4 ±1.09% (ranged from 0.7 to 1.9%) for the nine ETDRS areas. COV values increased with age; a significant correlation was found between them (r=0.300, p≤0.001). COVs were also related to VA.Conclusion Retinal thickness measurements obtained using Cirrus Fourier‐domain OCT show good reproducibility for healthy eyes. Repeatability is related to the subject age.

Macular parameters and prematurity: A spectral domain coherence tomography study

To investigate the association of premature birth with macular parameters measured by spectral domain coherence tomography (SD-OCT). The Sydney Adolescent Vascular and Eye Study performed eye examinations in school students across Sydney between 2009 and 2011. Visual acuity, cycloplegic autorefraction, and optical biometry measurements were recorded. Macular parameters were measured with SD-OCT. Questionnaires previously completed by the participants' parents were used to determine perinatal and medical history. Children with retinal disease or a known history of retinopathy of prematurity were excluded from the analysis. Macular measurements from the right eye of 1,672 participants ages 10-19 years were analyzed. The central subfield in those born at ≤32 weeks' gestational age was significantly thicker than those born at ≥37 weeks' gestational age (266.3 μm vs 251.7 μm, P = 0.0007). The average cube thickness and average outer macular ring thickness were smaller in those born at ≤32 weeks compared with those born at ≥37 weeks (P = 0.03 and 0.02, respectively). Similarly, the cube volume was smaller in the ≤32 weeks' group compared with the ≥37 weeks' group (P = 0.04). No significant differences were found between the 33-36 weeks' group and the ≥37 weeks' group. In comparison to babies born at term, thicker central maculas and thinner macular outer rings were found in children born <33 weeks gestational age when measured by SD-OCT at ages 10-19 years.

Prophylactic nepafenac and ketorolac versus placebo in preventing postoperative macular edema after uneventful phacoemulsification

To evaluate the efficacy of prophylactic ketorolac 0.5% versus nepafenac 0.1% versus placebo on macular volume 1 month after uneventful phacoemulsification and evaluate the health-related quality-of-life (HRQOL) of topical nonsteroidal antiinflammatory drugs (NSAIDs) in the context of cataract surgery. Hotel Dieu Hospital, Kingston, Ontario, Canada. Prospective placebo-controlled parallel-assignment double-masked randomized clinical trial. In this study, patients 18 years or older scheduled for routine phacoemulsification were randomized to a placebo, ketorolac 0.5%, or nepafenac 0.1% and dosed 4 times a day starting 1 day before surgery and continuing for 4 weeks. Spectral-domain macular cube ocular coherence tomography scans measuring central subfield thickness, macular cube volume, and average macular cube thickness were performed at baseline and 1 month postoperatively. The HRQOL metrics were determined with the Comparison of Ophthalmic Medications for Tolerability (COMTOL) questionnaire. Each study group comprised 54 patients. One month postoperatively, although a trend toward significance occurred for nepafenac and ketorolac, analysis of the means of differences showed no statistically significant differences between the 3 study groups (P=.2901). The COMTOL analysis found no difference in tolerability, compliance, side-effect frequency and bother, and effects on HRQOL between ketorolac and nepafenac compared with the placebo. One month after uneventful phacoemulsification, there was no difference in macular volume between the placebo, ketorolac, and nepafenac. Ketorolac and nepafenac were well tolerated with minimal side-effect profiles. Thus, for patients without risk factors having routine surgery, prophylactic topical NSAIDs are not recommended.

Ranibizumab for serous macular detachment in branch retinal vein occlusions

The purpose of this study was to compare the efficacy of intravitreal ranibizumab in the treatment of macular edema due to branch retinal vein occlusions (BRVO) with and without serous macular neuroretinal detachment (SMD). Forty-nine eyes of 49 patients with macular edema due to branch retinal vein occlusion (22 with SMD and 27 without SMD) were included in this prospective, parallel-group, comparative study. Intravitreal injection of ranibizumab was administered at baseline. Thereafter patients were followed monthly and further injections were performed in the presence of persistence or recurrence of macular thickening. Flattening of the macula was considered success. At the last visit, best-corrected visual acuity (BCVA), and spectral-domain optical coherence tomography (SD-OCT) quantitative parameters (central subfield thickness, cube volume, average cube thickness) were compared between groups. In patients with SMD, BCVA and all the SD-OCT quantitative parameters improved significantly after a mean number of 5.0 ranibizumab intravitreal injections through a median follow-up of 12.5 months (range, 7-34). In patients without SMD, all the variables analyzed improved significantly except for the cube volume, after a mean number of 4.3 ranibizumab intravitreal injections through a median follow-up of 10.4 months (range, 6.5-40.2). The numbers of injections were similar in both groups. The final BCVA was better in patients without SMD at baseline but without significant differences in the SD-OCT parameters between groups. The presence of SMD may be a baseline predictive factor for ranibizumab treatment outcomes in BRVO patients, with no influence in the number of treatments needed between patients with or without SMD at baseline. Further studies are needed in order to confirm the role of SMD as an independent predicitive factor in cases of BRVO.

Reinforcement of the Cube texture during recrystallization of a 1050 aluminum alloy partially recrystallized and 10% cold-rolled

In high purity Aluminum, very strong {100}<001> recrystallization texture is developed after 98% cold rolling and annealing at 500 °C. On the contrary, in Aluminum alloys of commercial purity, the Cube component hardly exceeds 30% after complete recrystallization. Parameters controlling Cube orientation development are mainly the solute dragging due to impurities in solid solution and the stored deformation energy. In the present study, besides the 85% cold rolling, two extra annealings and a slight cold rolling are introduced in the processing route to increase the Cube volume fraction. The Cube development was analyzed by X-ray diffraction and Electron BackScattered Diffraction (EBSD). The nucleation and growth mechanisms responsible for the large Cube growth were investigated using FEG/EBSD in-situ heating experiments. Continuous recrystallization was observed in Cube oriented grains and competed with SIBM (Strain Induced Boundary Migration) mechanism. This latter was favored by the stored energy gap introduced during the additional cold-rolling between the Cube grains and their neighbors. Finally, a Cube volume fraction of 65% was reached after final recrystallization. ► EBSD in-situ heating experiments of aluminum alloy of commercial purity. ► A 10% cold-rolling after a partial recrystallization improved Cube nucleation and growth. ► Annealing before cold-rolling limited the solute drag effect and permitted a large Cube growth. ► Cube development is enhanced by continuous recrystallization of Cube sub-grains. ► The preferential Cube growth occurs by SIBM of small Cube grains.