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Multifocal intraocular lenses (MFIOL) are associated with degradation in contrast sensitivity function (CSF); yet the contribution of vitreous is not known, nor is the benefit of vitrectomy.Prospective, nonrandomized clinical study.A total of 180 eyes of 180 patients (55 MFIOL, 60 monofocal intraocular lenses [MIOL], 65 phakic) with symptomatic vitreous opacities were enrolled. Vitreous structure was assessed with quantitative ultrasonography (QUS). Vision was evaluated with visual acuity and CSF measurements.Vitreous echodensity was the same in all lens cohorts, yet CSF was worse in MFIOL eyes (P.001). In 86 patients who elected vitrectomy, there was 68% greater vitreous echodensity and 31% worse CSF than in observation controls (P.0001 for each). Preoperatively, CSF was 25% worse in MFIOL than in MIOL (P = .014). Postoperatively, vitreous echodensity decreased by 55%, 51%, and 52%, whereas CSF improved by 37% 48% in and 43% in MFIOL, MIOL, and phakic eyes, respectively (P.0001 for each). NEI Visual Function Questionnaire analyses showed improved visual well-being.Patients with vision degrading myodesopsia who elected vitrectomy had greater vitreous echodensity and worse CSF than controls, but no other differences in age, sex, or myopia. MFIOL eyes had worse CSF than MIOL and phakic eyes, very possibly due to combined effects of the MFIOL and vitreous opacification. Limited vitrectomy reduced vitreous echodensity and improved CSF in all eyes. All patients with CSF-degrading vitreous opacities benefited from limited vitrectomy, including those with MFIOL. As MFIOL eyes had 37% improvement in CSF, patients with MFIOL and vision degrading myodesopsia merit consideration of vitrectomy.

PURPOSE: Limited vitrectomy improves vision degrading myodesopsia (VDM), but the incidence of recurrent floaters post-operatively is not known. We studied patients with recurrent central floaters using ultrasonography and contrast sensitivity (CS) testing to characterize this subgroup and identify the clinical profile of patients at risk of recurrent floaters. METHODS: 286 eyes (203 patients, 60.6±12.9 years old) undergoing limited vitrectomy for VDM were studied retrospectively. Sutureless 25G vitrectomy was performed without intentional surgical PVD induction. CS (Freiburg Acuity Contrast Test: Weber Index, %W) and vitreous echodensity (quantitative ultrasonography) were assessed prospectively. RESULTS: No eyes (0/179) with pre-operative PVD experienced new floaters. Recurrent central floaters occurred in 14/99 (14.1%) without complete pre-operative PVD (mean follow-up = 39 months vs. 31 months in the 85 without recurrent floaters). Ultrasonography identified new-onset PVD in all 14 (100%) recurrent cases. Young (

INTRODUCTION: Hyalocytes are sentinel macrophages residing within the posterior vitreous cortex anterior to the retinal inner limiting membrane (ILM). Following anomalous PVD and vitreoschisis, hyalocytes contribute to paucicellular (vitreo-macular traction syndrome, macular holes) and hypercellular (macular pucker, proliferative vitreo-retinopathy, proliferative diabetic vitreo-retinopathy) diseases. AREAS COVERED: Studies of human tissues employing dark-field, phase, and electron microscopy; immunohistochemistry; and in vivo imaging of human hyalocytes. EXPERT OPINION: Hyalocytes are important in early pathophysiology, stimulating cell migration and proliferation, as well as subsequent membrane contraction and vitreo-retinal traction. Targeting hyalocytes early could mitigate advanced disease. Ultimately, eliminating the role of vitreous and hyalocytes may prevent proliferative vitreo-retinal diseases entirely.

Myopic vitreopathy features precocious fibrous vitreous liquefaction and early posterior vitreous detachment (PVD). It is unclear whether visual function is affected by myopic vitreopathy and PVD. This study assessed the relationships among axial length, structural vitreous density, PVD, and visual function.Retrospective case-control study.Ultrasonography measurements were made of axial length, logMAR VA, contrast sensitivity function (CSF [Freiburg acuity contrast test]), and quantitative B-scan ultrasonography.Seventy-nine subjects (45 men and 34 women; mean age: 49 ± 14 years) were analyzed. Axial lengths ranged from 22 to 29.2 mm (mean: 24.9 ± 1.8 mm; myopic eyes: 26.35 ± 1.35 mm; and nonmyopic eyes: 23.45 ± 0.75 mm; P.001). With increasing axial length there was greater vitreous echodensity (R: 0.573; P.01) and degradation in CSF (R: 0.611; P.01). Subgroup analyses found that myopic eyes (- 3 diopters) had 37% more vitreous echodensity than nonmyopic eyes (762 ± 198 arbitrary units [AU] vs. 557 ± 171 AU, respectively; P.001) and that CSF was 53% worse in myopic eyes (3.30 ± 1.24 Weber index [%W]) than in nonmyopic eyes (2.16 ± .59 %W; P.001). Myopic eyes with PVD had 33% greater vitreous echodensity (815 ± 217 AU; P.001) and 62% degradation in CSF (3.63 ± 2.99 %W) compared to nonmyopic eyes with PVD (613 ± 159 AU; 2.24 ± 0.69 %W; P.001, each). Limited vitrectomy was performed in 11 of 40 cases (27.5%), normalizing vitreous echodensity and CSF in each case.Axial myopia is associated with increased fibrous vitreous liquefaction and echodensity, as well as profound degradation of CSF. PVD in myopic eyes is associated with even more structural and functional abnormalities, normalized by limited vitrectomy. These findings may explain some common complaints of myopic patients with respect to vision and quality of life.

Vision degrading myodesopsia (VDM) results from clinically significant vitreous opacities that reduce contrast sensitivity (CS) and visual quality of life (VQOL). Previous studies with a single clinical system for quantitative ultrasonography (QUS) found correlations with CS and VQOL as measured by the N.E.I. Visual Function Questionnaire (VFQ). Here, we evaluated a cohort of patients to determine if VDM as evaluated by QUS is machine independent. 28 eyes from 14 patients (age 56 ± 14 years) experiencing VDM were scanned with two different clinical ophthalmic ultrasound systems in succession: one with a 15-MHz single element transducer (23mm focal length, 7 mm aperture) and one with a 20 MHz annular array (five elements, 22 mm focal length, 9 mm total aperture). Images were acquired as a longitudinal plane through premacular vitreous in temporal gaze. Three QUS parameters and a composite score were computed from the vitreous region within each set of log-compressed envelope data and averaged over artifact-free frames. A linear regression comparing QUS parameters computed fromeach system showed statistically significant correlations (R ≥ 0.86, p

Vitreous opacities, which are collagen aggregates that form in the eye and cause vision impairment (eye floaters), are currently treated with invasive surgical intervention or high-energy laser photoablation. In this paper, the authors show that exposing gold nanoparticles or indocyanine green to low-energy laser pulses generates vapour nanobubbles that can disrupt collagen aggregates in the eyes of rabbit, suggesting a milder strategy for the treatment of eye floaters. In myopia, diabetes and ageing, fibrous vitreous liquefaction and degeneration is associated with the formation of opacities inside the vitreous body that cast shadows on the retina, appearing as 'floaters' to the patient. Vitreous opacities degrade contrast sensitivity function and can cause notable impairment in vision-related quality of life. Here we introduce 'nanobubble ablation' for safe destruction of vitreous opacities. Following intravitreal injection, hyaluronic acid-coated gold nanoparticles and indocyanine green, which is widely used as a dye in vitreoretinal surgery, spontaneously accumulate on collagenous vitreous opacities in the eyes of rabbits. Applying nanosecond laser pulses generates vapour nanobubbles that mechanically destroy the opacities in rabbit eyes and in patient specimens. Nanobubble ablation might offer a safe and efficient treatment to millions of patients suffering from debilitating vitreous opacities and paves the way for a highly safe use of pulsed lasers in the posterior segment of the eye.

Purpose Lamellar macular holes (LMHs) can been subdivided into tractional and degenerative subtypes. This cross-sectional cohort study compared structural and functional characteristics in these subtypes hypothesizing that tractional LMH has a higher prevalence of vitreopapillary adhesion and tangential traction (macular pucker), whereas degenerative LMH has more ellipsoid zone disruption and worse vision, measured three different ways. Methods Tractional LMH (n = 22) and degenerative LMH (n = 15) were distinguished by optical coherence tomography criteria. Separate spectral domain optical coherence tomography scanning of the macula and optic disk was performed. Visual acuity, contrast sensitivity function (Weber Index, %W), and the degree of visual distortions (3-dimensional threshold Amsler grid; % volume lost [%VL]) were quantified. Results Vitreopapillary adhesion was present in 14/22 (64%) tractional, but in only 3/15 (20%) degenerative LMH (P = 0.006). Macular pucker was present in 19/22 (86%) tractional, but in only 8/15 (53%) degenerative LMH (P = 0.011). Ellipsoid zone disruption was present in 13/15 (87%) degenerative, but in only 2/22 (9%) tractional LMH (P = 0.0001). Visual acuity was better in tractional than degenerative LMH (P = 0.006), as was contrast sensitivity function (tractional = 3.44 ± 1.07 %W, degenerative = 4.66 ± 1.73 %W; P = 0.015). Visual distortions were less in tractional (0.33 ± 0.61 %VL) than in degenerative (0.85 ± 0.68 %VL) LMH (P = 0.014). Conclusion Structure and visual function differ significantly in subtypes of LMH. Tractional LMH has 3-fold higher prevalence of vitreopapillary adhesion and 2-fold higher prevalence of macular pucker. Degenerative LMH has 9-fold more ellipsoid zone disruption, worse visual acuity and contrast sensitivity function, and 3-fold more distortions. Thus, outer retinal integrity seems more closely correlated with vision than anterior structural abnormalities in LMH.

Neodymium:yttrium-aluminum-garnet (Nd:YAG) laser treatment is performed on vitreous floaters, but studies of structural and functional effects with objective outcome measures are lacking. This study evaluated Nd:YAG laser effects by comparing participants with vitreous floaters who previously underwent laser treatment with untreated control participants and healthy persons without vitreous floaters using quantitative ultrasonography to evaluate vitreous structure and by measuring visual acuity and contrast sensitivity function to assess vision.Retrospective, comparative study.One eye was enrolled for each of 132 participants: 35 control participants without vitreous floaters, 59 participants with untreated vitreous floaters, and 38 participants with vitreous floaters previously Nd:YAG-treated. Of these, 25 were dissatisfied and sought vitrectomy; 13 were satisfied with observation.The 39-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-39) to assess participant visual well-being, quantitative ultrasonography (QUS) to measure vitreous echodensity, and best-corrected visual acuity (BCVA) and contrast sensitivity function (CSF) to evaluate vision.Results of NEI-VFQ-39, QUS, BCVA, and CSF.Compared with control participants without vitreous floaters, participants with untreated vitreous floaters showed worse NEI-VFQ-39 results, 57% greater vitreous echodensity, and significant (130%) CSF degradation (P0.001 for each). Compared with untreated eyes with vitreous floaters, Nd:YAG-treated eyes had 23% less vitreous echodensity (P0.001), but no differences in NEI-VFQ-39 (P = 0.51), BCVA (P = 0.42), and CSF (P = 0.17) results. Of 38 participants with vitreous floaters who previously were treated with Nd:YAG, 25 were dissatisfied and seeking vitrectomy, whereas 13 were satisfied with observation. Participants seeking vitrectomy showed 24% greater vitreous echodensity (P = 0.018) and 52% worse CSF (P = 0.006). Multivariate linear regression models confirmed these findings.As a group, participants previously treated with Nd:YAG laser for bothersome vitreous floaters showed less dense vitreous, but similar visual function as untreated control participants with vitreous floaters. Because some treated eyes showed less dense vitreous and better visual function than those of untreated control participants, a prospective randomized study of Nd:YAG laser treatment of vitreous is warranted, using uniform laser treatment parameters and objective quantitative outcome measures.

Purpose Patients afflicted with clinically significant vitreous floaters suffer from vision-degrading myodesopsia, characterized by impairment in contrast sensitivity function (CSF) and decreased quality of life. This study determined the cost-effectiveness of limited vitrectomy for this condition. Design Retrospective, interventional case series and third-party insurer cost-utility analysis. Methods Sixty-seven patients suffering from unilateral vitreous floaters (20 non-myopic patients with posterior vitreous detachment [PVD]; 17 myopic patients [>-2 diopters] without PVD; 30 myopic patients with PVD) completed the National Eye Institute Visual Function Questionnaire (VFQ-39) and were tested with best-corrected visual acuity (BCVA) and CSF measurements before and after limited vitrectomy. A reference case cost-utility analysis was performed. Results The mean VFQ-39 increased 19% (P Conclusions Limited vitrectomy for vision-degrading myodesopsia is clinically effective, in that it improves BCVA, CSF, and patient well-being. It is also highly cost-effective ($1,574/QALY), with an average cost-utility ratio vs. no therapy that is superior to cataract surgery ($2,262/QALY), amblyopia therapy ($2,710/QALY), and retinal detachment repair ($45,304/QALY). Myopic patients without PVD had the lowest cost-utility ratio of all ($1,338/QALY).

Purpose The purpose of this study was to characterize age-related changes in anterior human vitreous with 3-D swept source optical coherence tomography (SS-OCT) and evaluate associations with axial length (AL) and contrast sensitivity function (CSF). Methods There were 49 phakic eyes in 49 patients (40.0 ± 19.3 years) had 3-D volumetric scanning of the lens and retrolental vitreous with SS-OCT at 1050 nm. OCT-derived indices of vitreous optical density (VOD), vitreous opacification ratio (VOR), and lens optical density (LOD) were correlated with AL and double-pass assessment of retinal point spread function (Objective Scatter Index [OSI]). CSF was measured using an adaptive-optics visual simulator (area under log-log contrast sensitivity function [AULCSF]). Results Vitreous SS-OCT detected gel vitreous, liquefied lacunae, Berger's space, retrolental laminae, and fibrous opacifications. VOD, VOR, and LOD showed high reproducibility (intraclass correlation coefficients 0.968, 0.975, and 0.998, respectively). VOD was highly correlated with VOR (Pearson's R = 0.96, P < 0.000001). VOD, VOR, and LOD correlated with age (R = 0.48, 0.58, and 0.85, P < 0.001 for each). VOR and LOD correlated with OSI (R = 0.36, P = 0.0094, and R = 0.36, P = 0.0096, respectively). VOR correlated negatively with AULCSF (R = -0.53, P < 0.00009), which was related to OSI. Myopic eyes had higher OSI than nonmyopic eyes (P = 0.0121), consistent with correlation between OSI and AL (R = 0.37, P = 0.0091). Multivariable regression confirmed these findings. Conclusions SS-OCT visualized microstructural features of anterior human vitreous, where opacification is associated with increased light scattering and CSF degradation. SS-OCT enables high-resolution optical evaluation of vitreous opacities.

The vitreous body occupies a spherical space surrounded by the retina, lens, and pars plana of the eye. It consists primarily of water (98%) and macromolecules (2%), specifically collagen and hyaluronan. Vitreous plays an important role in the development of many common retinal pathologies including proliferative diabetic retinopathy (PDR), exudative age-related macular degeneration (AMD), and, via anomalous posterior vitreous detachment (APVD), retinal detachment (RD), macular holes, and macular pucker. Therefore, understanding vitreous anatomy is important to improve surgical approaches and techniques.

Contrast sensitivity function (CSF) declines with age. When unassociated with cataracts, this is hypothesized to be due to macular ganglion cell complex (GCC) thinning. However, other studies found associations with increased vitreous echodensity and posterior vitreous detachment (PVD). We investigate the relationship between CSF, vitreous echodensity, PVD, and GCC thickness as related to age in the same subjects. Age, CSF (Weber index: %W), vitreous echodensity (quantitative ultrasonography [QUS]), lens status (phakia or pseudophakia), best-corrected visual acuity (BCVA), and GCC thickness (SD-OCT) were evaluated in 57 eyes of 57 subjects with (n = 32, mean age = 62 years) and without (n = 25, mean age = 44 years) PVD (P

A computational model of vitreous oxygen consumption and transport predicts that limited vitrectomy will result in lower retrolental oxygen levels than extensive vitrectomy, and that higher retrolental oxygen would promote cataractogenesis. This study compared the incidence and timing of cataract surgery after limited versus extensive vitrectomy for vitreous opacities.Ninety-six phakic eyes in 75 patients (aged 55±14 years) underwent limited 25 G vitrectomy with preservation of 3 to 4 mm of retrolental vitreous and without surgical posterior vitreous detachment induction. Of these 96 eyes, 48 eyes in 37 patients (aged 56±14 years) had a minimum of 24 months' follow-up and were compared with 23 eyes from 18 patients (aged 63±8 years) who underwent extensive vitrectomy.Limited vitrectomy patients were older than extensive vitrectomy patients (P0.015), yet only 17 of 96 eyes (18%) required cataract surgery after limited vitrectomy (mean follow-up = 20±17 months). In eyes with a minimum follow-up of 24 months, 17 of 48 eyes (35%; age = 53-81 years) with limited vitrectomy required cataract surgery, versus 20 of 23 eyes (87%; age = 50-75 years) with extensive vitrectomy (P0.0001). Just before cataract surgery, visual acuity was comparable in each group (0.47±0.18 in the limited vitrectomy group vs. 0.54±0.30 in the extensive vitrectomy group; P = 0.23). Cataract surgery occurred an average of 12.4±5.1 months after limited vitrectomy, compared with 7.3±3.9 months after extensive vitrectomy (P0.002).The incidence of cataract surgery was lower after limited vitrectomy, which had a longer interval until cataract surgery compared with extensive vitrectomy. These findings are consistent with the computational model of oxygen consumption and transport and suggest clinical strategies to mitigate postvitrectomy cataractogenesis.

L’exercice des activites agricoles est confronte a des evolutions profondes et extremement rapides sous l’influence des nouvelles techniques et methodes d’organisation du travail. Cette etude realisee a Saris Congo, permet de mettre en exergue la contribution de la formation continue et du systeme documentaire dans l’amelioration des processus de production. Pour cela, nous nous sommes bases sur une recherche documentaire, completee par des entretiens semi-directifs ainsi que le recueil d’informations relatives a la formation des agents de la Direction des Cultures. Il ressort de cette etude, plusieurs types de formation : selon la duree, l’objectif de formation poursuivi, le statut de la personne et la formation sur le tas. Le taux d’acces a la formation est eleve chez les salaries ayant un CDI et dont le besoin en formation represente une priorite pour la maitrise de l’innovation, l’adaptation a l’evolution de l’emploi ou le renforcement des effectifs des agents de production. Le processus de formation represente un enjeu strategique dans la recherche de l’efficience, c’est pourquoi il est utile de l’inserer dans une dynamique d’assurance qualite ou les outils de la qualite joueront un role important.

Purpose To evaluate the effect of posterior vitreous detachment (PVD) on contrast sensitivity function (CSF) in previously normal eyes, with the hypothesis that PVD reduces CSF. Design Prospective observational case series. Methods At a single clinical practice 28 eyes were evaluated: 8 eyes of 8 adults (mean age 54.4 ± 10.1 years; range 39–68 years) with normal CSF documented by Freiburg Acuity Contrast Testing (Weber index: %W) who subsequently experienced PVD, as confirmed by ultrasonography and optical coherence tomography; 8 fellow eyes without PVD; and 12 control eyes: 9 eyes with PVD in patients who chose observation and 3 fellow eyes without PVD. Results At study entry there was no significant difference in CSF of fellow eye controls (mean 1.44 ± 0.27 %W; range 1.06–2.00 %W) and eyes that subsequently developed PVD (1.81 ± 0.61 %W; P = .146; range 1.01–2.69 %W). Following PVD there was a 52.5% reduction in CSF (2.76 ± 0.30 %W; P = .001; range 2.25–3.14 %W). CSF in the patients who chose limited vitrectomy (2.51 ± 0.46 %W; range 2.03–3.06 %W) was 41.8% worse than in the eyes with PVD of patients who chose observation (1.46 ± 0.21 %W; P = .001; range 1.08–1.87 %W). After vitrectomy, CSF improved by an average of 43.2%, normalizing in each case at 1 month (CSF 1.51 ± 0.28 %W; P = .001; range 1.14–2.00 %W), 3 months (1.38 ± 0.10 %W; P = .0002; range 1.28–1.51 %W), and 12 months (1.34 ± 0.34 %W; P = .0001; range 1.01–1.89 %W, n = 5) postoperatively, attaining the same CSF as the control fellow eyes (1.34 ± 0.20 %W; range 1.06–1.56 %W). Conclusion PVD is associated with significant reduction in CSF of previously normal eyes. This quantifiable negative impact on visual function can distinguish patients who are not significantly bothered by vitreous floaters from those with clinically significant symptoms.

Purpose To assess the accuracy of macular spectral-domain OCT in detecting complete posterior vitreous detachment (PVD). Design Evaluation of diagnostic test or technology using a retrospective comparative study. Participants One hundred seventy-five eyes in 175 patients (111 women and 64 men; mean age, 65 years) with preoperative OCT within 90 days of vitrectomy. Methods Posterior vitreous detachment status on preoperative macular OCT was compared with PVD determination during vitrectomy. Attached vitreous was identified on OCT by visualizing the posterior vitreous cortex or premacular bursa. Complete PVD was identified by the absence of these findings and considered a positive outcome for the purpose of analysis. Main Outcome Measures Sensitivity, specificity, positive predictive value, and negative predictive value of macular OCT for detection of complete PVD compared with findings at surgery. Results Of the 38 eyes graded as showing complete PVD on OCT, 20 eyes were found to have pre-existing PVD at the time of surgery (true-positive results), and 18 eyes were found to have attached vitreous at the time of surgery (false-positive results). Of the 137 eyes graded as showing attached vitreous on OCT, 129 eyes had attached vitreous at the time of surgery (true-negative results), and 8 eyes had pre-existing PVD at the time of surgery (false-negative results). The sensitivity of OCT for detecting complete PVD was 71% and the specificity was 88%. In the study population, the positive predictive value of an OCT scan showing complete PVD was 53%, whereas the negative predictive value of an OCT scan showing attached vitreous was 94%. Conclusions If the premacular bursa or posterior vitreous cortex are visualized on macular OCT, an accurate determination of attached vitreous can be made. The diagnosis of complete PVD by macular OCT is less accurate and requires ultrasound.

Aims Preoperative short-course radiotherapy (SCRT) is an important treatment option for rectal cancer. The length of time between completing SCRT and surgery may influence postoperative outcomes, but the evidence available to determine the optimal interval is limited and often conflicting. Materials and methods Information was extracted from a colorectal cancer data repository (CORECT-R) on all surgically treated rectal cancer patients who received SCRT in the English National Health Service between April 2009 and December 2014. The time from radiotherapy to surgery was described across the population. Thirty-day postoperative mortality, returns to theatre, length of stay and 1-year survival were investigated in relation to the interval between radiotherapy and surgery. Results Within the cohort of 3469 patients, the time to surgery was 0–7 days for 76% of patients, 8–14 days for 19% of patients and 15–27 days for 5% of patients. There was a clear variation in relation to different patient characteristics. There was, however, no evidence of differences in postoperative outcomes in relation to interval length. Conclusions This study suggests that the time interval between SCRT and surgery does not influence postoperative outcomes up to a year after surgery. The study provides population-level, real-world evidence to complement that from clinical trials., Highlights • The optimal interval between SCRT and rectal surgery is not known. • SCRT and surgery intervals vary substantially across the English NHS. • There are no differences in surgical outcomes with intervals of up to 27 days after SCRT.

Transparency of ocular structures is an important factor determining contrast in the retinal image. Although opacities are most commonly formed in the crystalline lens of aging eye (cataract formation), visual function can be also altered by the opacities in the vitreous body. Therefore, macro- and micro-scale visualization of vitreous is clinically relevant since alterations of vitreous organization impact retinal diseases and affect vision. However, optical imaging of the vitreous body is challenging due to its transparency. We demonstrate visualization of vitreous and its opacities in vivo using optical coherence tomography (OCT). We developed a prototype long-depth-range Swept-Source OCT instrument operating at the speed of 30 kA-scans/second and at the central wavelength of 1 μm to perform high-resolution imaging through the entire vitreous depth. The interface with focus-tunable optics has been used to optimize the field of view. 2-D and 3-D OCT data sets of eyes with vitreous opacities were acquired and processed to obtain contrast-enhanced high-resolution images of vitreous. The results demonstrate the ability of the OCT imaging to characterize the opacities that cause floaters. In conclusion, long-depth-range SS-OCT enables volumetric visualization of in vivo microstructural changes in the vitreous body. This instrument might be a useful tool in high-resolution evaluation and surgical management of vitreous opacities.

Myopia, diabetes, and aging are the main causes of progressive vitreous collagen aggregation, resulting in vitreous opacities, which can significantly disturb vision. As vitreous opacities, which induce the visual phenomenon of "floaters", are accessible with nanomaterials and light, we propose a nanotechnology-based approach to locally ablate them with highly reduced light energy compared to the more traditional YAG laser therapy. Our strategy relies on the plasmon properties of gold nanoparticles that generate vapor nanobubbles upon pulsed-laser illumination whose mechanical force can ablate vitreous opacities. We designed gold nanoparticles coated with hyaluronic acid (HA), which have excellent diffusional mobility in human vitreous, an essential requirement to reach the vitreous opacities. In addition, we found that HA-coated gold nanoparticles can accumulate extensively on human vitreous opacities that were obtained by vitrectomy from patients with vision-degrading myodesopsia. When subsequently applying nanosecond laser pulses, the collagen aggregates were efficiently destroyed with similar to 1000 times less light energy than typically used in YAG laser therapy. This low-energy "floater-specific destruction", which is due to the accumulation of the small gold nanoparticles on the opacities, is attractive, as it may be safer to the surrounding ocular tissues while at the same time being easier and faster to apply compared to YAG laser therapy, where the opacities need to be ablated piece by piece by a tightly focused laser beam. Gold nanoparticle-assisted photoablation may therefore provide a safer, faster, and more reliable destruction of vitreous opacities in the treatment of ophthalmologic diseases.

To measure the effects of macular pucker (MP) on macular structure and quantify function by measuring visual acuity (VA), contrast sensitivity (CS), and distortions. The effects of surgery were quantitatively evaluated using these measures.Prospective, comparative case series.Fifty-three patients with unilateral MP and normal fellow eyes: 24 operated MP subjects, 17 unoperated controls, and 12 reproducibility subjects.Posterior vitreous detachment was diagnosed by ultrasound and ellipsoid zone disruption (EZD) was determined by OCT, which also measured macular thickness and volume. Vision was assessed, by measuring VA (logMAR) and CS (Freiburg acuity contrast testing: Weber index, %W). A visual distortions index (%DI) was calculated using 3-dimensional threshold Amsler grid testing. Comparisons to controls were performed before surgery and at 1, 3, 6, and 12 months after vitrectomy/membrane peel without chromodissection.Posterior vitreous detachment (ultrasound), EZD (OCT), macular thickness and volume (OCT), VA (logMAR), CS (%W), distortions (%DI).Posterior vitreous detachment was present in 90% of MP eyes, but only 50% of fellow eyes (P 0.001). All structural and functional indices were worse (28% to 5-fold) in the 24 operated MP eyes than the 17 unoperated MP eyes (P0.001). Before surgery, EZD was present in 33% of operated MP eyes but none of the unoperated MP eyes (P0.02). The macula was thicker (514±85 μm vs. 257±59 μm; P0.001) with greater volume (3.22±0.56 μl vs. 2.14±0.22 μl; P0.001) in operated MP eyes than normal fellow eyes. Before surgery, MP eyes had VA = 0.53 logMAR (Snellen equivalent, 20/67) vs. controls = 0.21 (20/32); P0.001; CS was 8.61±5.36 %W vs. controls = 3.71±1.47 %W (P0.001); and distortions were 7.61±12.6 %DI vs. controls = 0.13±0.61 %DI (P0.001). EZD was associated with worse VA (P0.01) and CS (P0.03) before and after surgery. Each outcome measure improved progressively at 1, 3, 6, and 12 months after surgery, but only %DI and macular volume normalized.These quantitative measures characterize the impact of MP on macular structure and function. All indices improved after surgery, but only distortions and macular volume normalized. Contrast sensitivity measurements and quantification of distortions can objectively assess visual dysfunction in MP and may be useful outcome measures of therapy.

Macromolecules comprise only 2% of vitreous, yet are responsible for its gel state, transparency, and physiologic function(s) within the eye. Myopia and aging alter collagen and hyaluronan association causing concurrent gel liquefaction and fibrous degeneration. The resulting vitreous opacities and collapse of the vitreous body during posterior vitreous detachment are the most common causes for the visual phenomenon of vitreous floaters. Previously considered innocuous, the vitreous opacities that cause floaters sometimes impact vision by profoundly degrading contrast sensitivity function and impairing quality-of-life. While many people adapt to vitreous floaters, clinically significant cases can be diagnosed with Vision Degrading Myodesopsia based upon echographic assessment of vitreous structure and by measuring contrast sensitivity function. Perhaps due to the ubiquity of floaters, the medical profession has to date largely ignored the plight of those with Vision Degrading Myodesopsia. Improved diagnostics will enable better disease staging and more accurate identification of severe cases that merit therapy. YAG laser treatments may occasionally be slightly effective, but vitrectomy is currently the definitive cure. Future developments will usher in more informative diagnostic approaches as well as safer and more effective therapeutic strategies. Improved laser treatments, new pharmacotherapies, and possibly non-invasive optical corrections are exciting new approaches to pursue. Ultimately, enhanced understanding of the underlying pathogenesis of Vision Degrading Myodesopsia should result in prevention, the ultimate goal of modern Medicine.

The transparent vitreous body, which occupies about 80% of the eye’s volume, is laden with numerous enzymatic and non-enzymatic antioxidants that could protect the eye from oxidative stress and disease. Aging is associated with degeneration of vitreous structure as well as a reduction in its antioxidant capacity. A growing body of evidence suggests these age-related changes may be the precursor of numerous oxidative stress-induced vitreo-retinopathies, including vision degrading myodesopsia, the clinically significant entoptic phenomena that can result from advanced vitreous degeneration. Adequate intravitreal antioxidant levels may be protective against vitreous degeneration, possibly preventing and even improving vision degrading myodesopsia as well as mitigating various other vitreo-retinopathies. The present article is, therefore, a review of the different antioxidant molecules within vitreous and the inter-relationships between vitreous antioxidant capacity and degeneration.

Asteroid hyalosis is a relatively common cause of vitreous opacities, which is possibly associated with diabetes mellitus and hereditary pigmentary retinopathies. We review the history, epidemiology, and biochemistry of asteroid hyalosis, as well as its relationship with ocular and systemic conditions. We describe imaging modalities used for diagnostic evaluations in cases of severe asteroid hyalosis and propose hypotheses regarding its lack of significant effects on vision. We discuss cataract surgery in patients with asteroid hyalosis and the selection of intraocular lenses for implantation.

Vitreous floaters can lower visual acuity (VA) and degrade contrast sensitivity function (CSF). Limited vitrectomy improves VA and normalizes CSF, but long-term results in a large series with objective quantitative outcome measures are lacking.Case series.One hundred ninety-five eyes of 145 patients (87 men, age = 57.6 ± 4.3 years; 58 women, age = 61.5 ± 12.0 years) reporting bothersome vitreous floaters were compared to 70 age-matched controls. Posterior vitreous detachment (PVD) alone was the cause in 96/195 (49.2%), myopic vitreopathy alone was the cause in 30/195 (15.4%), PVD with myopic vitreopathy was the cause in 56/195 (28.7%), and asteroid hyalosis was the cause in 13/195 eyes (6.7%).Limited vitrectomy with 25-gauge instruments was performed without surgical PVD induction, preserving 3 to 4 mm of retrolental vitreous in phakic eyes. Follow-up averaged 32.6 ± 23.5 months (range, 3-115 months), with 2 years or more in 144 eyes, 3 years or more in 69 eyes, 4 years or more in 51 eyes, and 5 years or more in 24 eyes.Visual acuity, 39-item National Eye Institute Visual Function Questionnaire (VFQ) results, CSF (Weber index), and quantitative ultrasonography results.After surgery, vitreous echodensity decreased by 94.1% (P0.0001) and VFQ results improved by 19.3% (P0.0001). Preoperative VA was 0.68 ± 0.21, improving to 0.77 ± 0.19 after surgery (P0.0001). Preoperative CSF was degraded by 91.3% compared with controls (P0.0001), normalizing at 1, 3, 6, 12, 24, 36, and 48 months after surgery (P0.00005 for each). There were no cases of endophthalmitis. There were 3 retinal tears and 3 retinal detachments that underwent successful repair. Clinically significant vitreous hemorrhage developed in 2 patients, clearing spontaneously. Two macular puckers and 4 recurrent floaters from new PVD were cured by re-operation. Cataract surgery occurred in 21 of 124 patients (16.9%; mean age, 64 ± 7 years; none younger than 53 years), an average of 13.1 ± 6.8 months after vitrectomy.Limited vitrectomy for Vision Degrading Vitreopathy decreases vitreous echodensity, improves patient well-being, improves VA, and normalizes CSF. The long-term efficacy and safety profiles suggest this may be a safe and effective treatment for clinically significant vitreous floaters, warranting a prospective randomized trial.

Das vitreoretinale Interface bzw. die vitreoretinale Grenzflache setzt sich aus der inneren Grenzmembran der Netzhaut, der Glaskorperrinde und einer umgebenden extrazellularen Matrix zusammen. Hyalozyen sind mononukleare Phagozyten, die in der Glaskorperrinde als einschichtiger Zellverband eingebettet sind. Im Bereich der Makula konnen im Rahmen der inkompletten hinteren Glaskorperabhebung Adhasionen der Glaskorperrinde in ihrer gesamten Dicke wie beim vitreomakularen Traktionssyndrom entstehen oder nach lamellarer Aufspaltung der Glaskorperrinde persistieren (Vitreoschisis). Im Rahmen einer inkompletten hinteren Glaskorperabhebung mit Vitreoschisis entstehen relativ dunne hypozellulare Membranen, wenn die Dissektion innerhalb der Glaskorperrinde hinter der Ebene der als Monolayer angeordneten Hyalozyten erfolgt. Vollzieht sich die Spaltbildung anterior der Hyalozyten, resultieren zellreiche, dicke Membranen. Persistierende vitreopapillare Adhasionen begunstigen eine nach ausen gerichtete tangentiale Traktion und sind daher oft mit Makulaforamina assoziiert. Nach innen gerichtete Traktion resultiert im Krankheitsbild des „macular pucker“, hier sind persistierende vitreopapillare Adhasionen sehr selten.

Future advances in ophthalmology will see a paradigm shift in diagnostics from a focus on dysfunction and disease to better measures of psychophysical function and health. Practical methods to define genotypes will be increasingly important and non-invasive nanotechnologies are needed to detect molecular changes that predate histopathology.This is not a review nor meant to be comprehensive. Specific topics have been selected to illustrate the principles of important paradigm shifts that will influence the future of ophthalmic diagnostics. It is our impression that future evaluation of vision will go beyond visual acuity to assess ocular health in terms of psychophysical function. The definition of disease will incorporate genotype into what has historically been a phenotype-centric discipline. Non-invasive nanotechnologies will enable a paradigm shift from disease detection on a cellular level to a sub-cellular molecular level.Vision can be evaluated beyond visual acuity by measuring contrast sensitivity, color vision, and macular function, as these provide better insights into the impact of aging and disease. Distortions can be quantified and the psychophysical basis of vision can be better evaluated than in the past by designing tests that assess particular macular cell function(s). Advances in our understanding of the genetic basis of eye diseases will enable better characterization of ocular health and disease. Non-invasive nanotechnologies can assess molecular changes in the lens, vitreous, and macula that predate visible pathology. Oxygen metabolism and circulatory physiology are measurable indices of ocular health that can detect variations of physiology and early disease.This overview of paradigm shifts in ophthalmology suggests that the future will see significant improvements in ophthalmic diagnostics. The selected topics illustrate the principles of these paradigm shifts and should serve as a guide to further research and development. Indeed, successful implementation of these paradigm shifts in ophthalmology may provide useful guidance for similar developments in all of healthcare.

Cette etude s’inscrit dans le cadre d’un projet de mise en place d’un systeme qualite a la direction des cultures de Saris Congo. Le diagnostic organisationnel de cette direction a permis, a travers l’approche processus, d’identifier les activites critiques, empechant les differents processus de se realiser convenablement. A partir des outils de la qualite utilises au cours d’analyse processus, il a ete possible d’etablir la cartographie des processus, de proceder a la description de chaque processus de realisation et d’identifier les differentes interactions entre les activites d’un meme processus. L’interet des processus se trouve dans la relation client et fournisseur interne et permet donc d’augmenter l’efficacite du diagnostic, tout en s’inserant dans une demarche d’amelioration continue.

The optical alignment of the Large Synoptic Survey Telescope (LSST) is potentially challenging, due to its fast three-mirror optical design and its large 3.5° field of view (FOV). It is highly advantageous to align the three-mirror optical system prior to the integration of the complex science camera on the telescope, which corrects the FOV via three refractive elements and includes the operational wavefront sensors. A telescope alignment method based on nodal aberration theory (NAT) is presented here to address this challenge. Without the science camera installed on the telescope, the on-axis imaging performance of the telescope is diffraction-limited, but the field of view is not corrected. The nodal properties of the three-mirror telescope design have been analyzed and an alignment approach has been developed using the intrinsically linear nodal behavior, which is linked via sensitivities to the misalignment parameters. Since mirror figure errors will exist in any real application, a methodology to introduce primary-mirror figure errors into the analysis has been developed and is also presented.

Resume Introduction L’incontinence urinaire feminine entraine un desagrement physique et psychologique important. Jusqu’a present, aucune etude n’a evalue l’impact de la reeducation perineo-sphincterienne sur la qualite de vie comme critere de jugement principal. Cela a donc ete notre objectif. Methode Quarante-huit femmes vues en bilan urodynamique ont ete reparties en deux groupes : un groupe traite ayant beneficie de reeducation perineale (22 patientes) et un groupe temoin sans traitement (26 patientes). Vingt-trois cas (52,3 %) avaient une incontinence urinaire d‘effort et 21 cas (47,7 %) mixte. La qualite de vie, critere de jugement principal, etait evaluee par le score de l’autoquestionnaire CONTILIFE. Resultats La qualite de vie des patientes du groupe traite a ete significativement amelioree pour chaque parametre teste. Le groupe temoin montre une amelioration significative pour le retentissement sur l’activite quotidienne, le parametre emotionnel et le score total. Entre les deux groupes, on retrouve des differences significatives pour chaque parametre, sauf pour le retentissement sur l’activite quotidienne et l’activite sexuelle. Conclusion La qualite de vie des patientes du groupe traite a ete significativement amelioree. Il est donc licite de prescrire systematiquement des seances de reeducation pour toutes les patientes souffrant d’incontinence urinaire, apres un interrogatoire cible et un examen clinique complet. Le bilan urodynamique est systematique dans le cadre de l’urgenturie ou en cas d’echec de la reeducation comme le suggerent les recommandations.

Le vitre est concu pour etre normalement invisible. Son examen clinique est donc difficile : il a considerablement beneficie des nouveaux moyens d’exploration, loupes sans contact et tomographie a coherence optique (OCT). Le vitre anterieur est accessible a un examen simple au biomicroscope, l’examen du vitre central est realise avec un verre de contact ou une lentille convexe sans contact. L’examen du vitre peripherique necessite un verre a trois miroirs de Goldmann. La structure du vitre est complexe, constituee d’acide hyaluronique, de fibres de collagene, de hyalocytes et d’eau. Les modifications liees a l’âge sont nombreuses, aboutissant le plus souvent a une liquefaction plus ou moins importante du vitre et s’accompagnant d’un decollement posterieur de celui-ci. Les alterations pathologiques du vitre jouent un role dans la genese des dechirures retiniennes et des decollements de retine, des degenerescences palissadiques du retinoschisis liees au sexe, des membranes epiretiniennes premaculaires, des trous maculaires, des neovascularisations preretiniennes, et des proliferations vitreoretiennes.

The vitreoretinal interface consists of the inner limiting membrane of the retina, the posterior vitreous cortex, and an intervening extracellular matrix. Hyalocytes are mononuclear phagocytes embedded in the posterior vitreous cortex, in a single layer of sparse density. At the macula, anomalous posterior vitreous detachment (PVD) results in either full-thickness vitreous cortex adhesion with vitreomacular traction syndrome, or partial-thickness adhesion due to vitreoschisis, a split in the posterior vitreous cortex. Anomalous PVD with vitreoschisis splitting behind the level of the monolayer of hyalocytes leaves a relatively thin hypocellular membrane attached to the macula. Vitreoschisis anterior to the level of the hyalocytes leaves a thicker cellular membrane. Persistent vitreopapillary adhesion promotes outward (from the fovea) tangential traction and is therefore associated with macular holes. Inward (centripetal) tangential traction results in macular pucker, almost always in the absence of persistent vitreopapillary adhesion. The English full-text version of this article is available at SpringerLink (under supplemental).

PurposeClinical evaluation of floaters lacks quantitative assessment of vitreous structure. This study used quantitative ultrasound (QUS) to measure vitreous opacities. Since floaters reduce contrast sensitivity (CS) and quality of life (Visual Function Questionnaire [VFQ]), it is hypothesized that QUS will correlate with CS and VFQ in patients with floaters.MethodsTwenty-two eyes (22 subjects; age = 57 ± 19 years) with floaters were evaluated with Freiburg acuity contrast testing (FrACT; %Weber) and VFQ. Ultrasonography used a customized probe (15-MHz center frequency, 20-mm focal length, 7-mm aperture) with longitudinal and transverse scans taken in primary gaze and a horizontal longitudinal scan through premacular vitreous in temporal gaze. Each scan set had 100 frames of log-compressed envelope data. Within each frame, two regions of interest (ROIs) were analyzed (whole-central and posterior vitreous) to yield three parameters (energy, E; mean amplitude, M; and percentage of vitreous filled by echodensities, P50) averaged over the entire 100-frame dataset. Statistical analyses evaluated E, M, and P50 correlations with CS and VFQ.ResultsContrast sensitivity ranged from 1.19%W (normal) to 5.59%W. All QUS parameters in two scan positions within the whole-central ROI correlated with CS (R > 0.67, P < 0.001). P50 in the nasal longitudinal position had R = 0.867 (P < 0.001). Correlations with VFQ ranged from R = 0.52 (P < 0.013) to R = 0.65 (P < 0.001).ConclusionsQuantitative ultrasound provides quantitative measures of vitreous echodensity that correlate with CS and VFQ, providing objective assessment of vitreous structure underlying the functional disturbances induced by floaters, useful to quantify vitreous disease severity and the response to therapy.

Author(s): Carbonelli, Michele; La Morgia, Chiara; Savini, Giacomo; Cascavilla, Maria Lucia; Borrelli, Enrico; Chicani, Filipe; do V F Ramos, Carolina; Salomao, Solange R; Parisi, Vincenzo; Sebag, Jerry; Bandello, Francesco; Sadun, Alfredo A; Carelli, Valerio; Barboni, Piero | Abstract: PurposeTo investigate the thickness of the retinal layers and to assess the prevalence of macular microcysts (MM) in the inner nuclear layer (INL) of patients with mitochondrial optic neuropathies (MON).MethodsAll patients with molecularly confirmed MON, i.e. Leber's Hereditary Optic Neuropathy (LHON) and Dominant Optic Atrophy (DOA), referred between 2010 and 2012 were enrolled. Eight patients with MM were compared with two control groups: MON patients without MM matched by age, peripapillary retinal nerve fiber layer (RNFL) thickness, and visual acuity, as well as age-matched controls. Retinal segmentation was performed using specific Optical coherence tomography (OCT) software (Carl Zeiss Meditec). Macular segmentation thickness values of the three groups were compared by one-way analysis of variance with Bonferroni post hoc corrections.ResultsMM were identified in 5/90 (5.6%) patients with LHON and 3/58 (5.2%) with DOA. The INL was thicker in patients with MON compared to controls regardless of the presence of MM [133.1±7μm vs 122.3±9μm in MM patients (pl0.01) and 128.5±8μm vs. 122.3±9μm in no-MM patients (pl0.05)], however the outer nuclear layer (ONL) was thicker in patients with MM (101.4±1mμ) compared to patients without MM [77.5±8mμ (pl0.001)] and controls [78.4±7mμ (pl0.001)]. ONL thickness did not significantly differ between patients without MM and controls.ConclusionThe prevalence of MM in MON is low (5-6%), but associated with ONL thickening. We speculate that in MON patients with MM, vitreo-retinal traction contributes to the thickening of ONL as well as to the production of cystic spaces.