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2.
J Phys Condens Matter ; 34(13)2022 Jan 26.
Article in English | MEDLINE | ID: mdl-35016166

ABSTRACT

This paper describes the observation of non-equilibrium field effects at room temperature in four disordered insulating systems: granular Al, discontinuous Au, amorphous NbSi and amorphous indium oxide thin films. The use of wide enough gate voltage ranges and a cautious analysis of the data allow us to uncover memory dips (MDs), the advocated hallmark of the electron glass, in the four systems. These MDs are found to relax slowly over days of measurements under gate voltage changes, reflecting the impossibility for the systems to reach an equilibrium state within experimentally accessible times. Our findings demonstrate that these electrical glassy effects, so far essentially reported at cryogenic temperatures, actually extend up to room temperature.

3.
J Fr Ophtalmol ; 43(10): 1047-1053, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33004191

ABSTRACT

Intravitreal anti-vascular epithelial growth factor (anti-VEGF) injections have revolutionised the treatment of macular diseases, but can be stressful for the patient. We surveyed 904 patients receiving injections at 5 centres in France regarding their feelings toward anti-VEGF injections. The mean age was 77.4 years, and the injections were performed mostly for age related macular degeneration (72%). Half of the patients had previously received>10 injections, 35.6% had received 3-10 injections, and 14.2% had received<3 injections. The mean (SD) stress score was 4.2 [on a scale from 1-10 (0=least stressful, 10=extremely stressful)]. Most patients (70%) reported low to moderate stress (score ≤5). The number of previous injections did not influence stress scores. Paradoxically, 61.2% of patients reported finding injections to be less stressful over time. Most patients found injections to be less traumatic than expected (64%) or just as they had anticipated (25%). Most patients (88%) were not bothered by the presence of other patients in the waiting room. Most patients (78.8%) preferred to be injected quickly before they had time to feel stressed about the procedure. Injections were generally well accepted; most patients would prefer to maintain their current schedule of injections and their current vision (55.7%), or would be willing to have more frequent injections for better vision (39.5%). Our results suggest that stress appears to be more related to the patient's psychological make-up than to the treatment experience or the number of injections received.


Subject(s)
Angiogenesis Inhibitors/administration & dosage , Anxiety/epidemiology , Intravitreal Injections/psychology , Macular Degeneration/drug therapy , Patient Satisfaction/statistics & numerical data , Stress, Psychological/epidemiology , Vascular Endothelial Growth Factor A/immunology , Adult , Aged , Aged, 80 and over , Angiogenesis Inhibitors/adverse effects , Anxiety/etiology , Female , France/epidemiology , Humans , Intravitreal Injections/adverse effects , Macular Degeneration/epidemiology , Male , Middle Aged , Postoperative Complications/epidemiology , Postoperative Complications/psychology , Stress, Psychological/etiology , Surveys and Questionnaires , Vascular Endothelial Growth Factor A/antagonists & inhibitors
4.
J Fr Ophtalmol ; 43(3): 197-204, 2020 Mar.
Article in French | MEDLINE | ID: mdl-32000989

ABSTRACT

PURPOSE: The goal of this study was to investigate the safety and efficacy of the intravitreal dexamethasone implant (DI) for patients with diabetic macular edema (DME) in real life. METHODS: We conducted a monocentric retrospective analysis of the change in visual acuity and central macular thickness (CMT) after intravitreal injection of the DI at peak efficacy (2 months after injection) as well as the timing of reinjections and complications in patients with a loss of vision due to DME. RESULTS: Forty eyes of 33 patients were included, with a mean follow-up of 12.6 months. Thirty percent of the eyes experienced an increase in best corrected visual acuity (BCVA)>15 letters at peak efficacy (P<0.05) after each ID injection. Treatment-naive patients had a sustained response after Ozurdex injection, with better visual acuity at 3 months (P=0.02) and 4 months (P=0.04) than non-naïve patients and better visual acuity at 6 months despite identical baseline visual acuity (P<0.05). Anatomical efficacy was good, with approximately 60% of patients with CMT<300 microns at peak efficacy after each injection of ID. Thirty percent of eyes demonstrated ocular hypertension (OHT)>25mmHg at peak efficacy, and 12.5% of eyes required cataract surgery during follow-up. CONCLUSION: The DI has good functional and anatomic efficacy in these patients, with a good safety profile. Treatment-naïve patients with more recent DME had a more sustained increase in visual acuity after the injections and better visual recovery at 6 months. This encourages us to initiate DI therapy early if there is no response to anti-vascular endothelial growth factor (anti-VEGF) treatment.


Subject(s)
Dexamethasone/administration & dosage , Dexamethasone/adverse effects , Diabetic Retinopathy/drug therapy , Macular Edema/drug therapy , Aged , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/pathology , Diabetic Retinopathy/epidemiology , Drug Implants , Female , Fovea Centralis/diagnostic imaging , Fovea Centralis/drug effects , Fovea Centralis/pathology , France/epidemiology , Humans , Intravitreal Injections , Macular Edema/epidemiology , Male , Middle Aged , Retrospective Studies , Risk Factors , Treatment Outcome , Visual Acuity/drug effects
7.
J Fr Ophtalmol ; 40(9): 723-730, 2017 11.
Article in French | MEDLINE | ID: mdl-29055730

ABSTRACT

PURPOSE AND CONTEXT: Intravitreal administration of anti-VEGF agents, available in France since 2007, allows stabilization and improvement in visual acuity in wet age-related macular degeneration (AMD). In the past few years, the management of this disease has evolved in terms of both diagnostic methods and treatment schedules, which have been adapted to the pathophysiology of AMD. The goal of this survey, performed in a representative sample of French ophthalmologists, was to describe the evolution of medical practices one year after a similar survey (Massé et al., J Fr Ophtalmol 2016; 39: 40-7). METHOD: The survey was performed from December, 2014 to March, 2015 in 191 ophthalmologists (53 general ophthalmologists and 98 retina specialists) with an on-line questionnaire. This questionnaire was designed by a committee of ophthalmologists to describe practices concerning screening, diagnosis, treatment and follow-up of wet AMD. RESULTS: An initial intravitreal injection of an anti-VEGF agent was usually performed within 10 days after the diagnosis of wet AMD by 98% of ophthalmologists and within 5 days by 63%. The treatment protocols favored by retina specialists were pro re nata (PRN) for 58%, Observe and Plan for 25% and Treat and Extend for 17%. Bilateral intravitreal injections were performed on the same day by 46% of retina specialists, mostly for the convenience of the patient and because of the low infectious risk. The initial protocol was maintained by one third of retina specialists throughout the course of treatment, while two thirds of them reported that they reassessed the protocol on average after 5 months. CONCLUSION: This survey on the practices of the ophthalmologists in wet AMD highlights an improvement in the time course of patient management and an evolution of treatment schedules toward individualized protocols.


Subject(s)
Critical Pathways , Practice Patterns, Physicians' , Wet Macular Degeneration/therapy , Adult , Angiogenesis Inhibitors/administration & dosage , Bevacizumab/administration & dosage , Clinical Protocols , Critical Pathways/history , Critical Pathways/statistics & numerical data , Critical Pathways/trends , Female , France/epidemiology , History, 21st Century , Humans , Intravitreal Injections , Male , Middle Aged , Ophthalmologists/statistics & numerical data , Practice Patterns, Physicians'/history , Practice Patterns, Physicians'/statistics & numerical data , Practice Patterns, Physicians'/trends , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Wet Macular Degeneration/epidemiology
8.
J Phys Condens Matter ; 29(45): 455602, 2017 Nov 15.
Article in English | MEDLINE | ID: mdl-28885194

ABSTRACT

Insulating granular aluminum is one of the proto-typical disordered insulators whose low temperature electrical conductance exhibits ubiquitous non-equilibrium phenomena. These include slow responses to temperature or gate voltage changes, characteristic field effect anomalies and ageing phenomena typical of a glass. In this system the influence of temperature on the glassy dynamics has remained elusive. A similar situation was met in insulating indium oxide and it was concluded that in high carrier density Anderson insulators, electronic slow relaxations essentially proceed via activationless processes. In this work we experimentally demonstrate that thermal effects do play a role and that the slow dynamics in granular aluminum is subject to thermal activation. We show how its signatures can be revealed and activation energy distributions can be extracted, providing a promising grasp on the nature of the microscopic mechanism at work in glassy Anderson insulators. We explain why some of the experimental protocols previously used in the literature fail to reveal thermal activation in these systems. Our results and analyses call for a reassessment of the emblematic case of indium oxide, and question the existence of purely activationless dynamics in any of the systems studied so far.

10.
J Fr Ophtalmol ; 40(5): 408-413, 2017 May.
Article in French | MEDLINE | ID: mdl-28336283

ABSTRACT

PURPOSE: To assess early efficacy of dexamethasone intravitreal implant 0.7mg (OZURDEX®) at the time of peak efficacy (2 months after injection) in patients with decreased visual acuity secondary to diabetic macular edema (DME). MATERIALS AND METHODS: Retrospective monocentric study. Inclusion criteria were best-corrected visual acuity (BCVA)≤70 letters (20/40) due to DME and central retinal thickness (CRT)≥300 microns (Cirrus 2, Carl Zeiss Meditec, Inc, Dublin). Enrolled patients could be treatment naive or not (after failure of laser photocoagulation and/or anti-VEGF therapy). Follow-up was at least 6 months. Our primary endpoint was BCVA gain at M2 after injection. Secondary endpoints were best-corrected visual acuity at 2 and 4 months, central retinal thickness at 2 and 4 months, mean interval between 2 injections, and adverse events. RESULT: Nineteen eyes of 19 patients were included in this study. The mean age was 67.45 years, sex ratio was 2.17 men/women, and the patients were all type 2 diabetics. Three of 19 patients were treatment naive for anti-VEGF intravitreal injection, and 52.3% were pseudophakic (10/19 patients). The mean gain of BCVA at M2 was +7.7 letters. The mean BCVA was 51.1 ETDRS letters at baseline and 58.8 at M2. Mean CRT was 568.9µm at baseline and 291.2µm at M2. Treatment with dexamethasone implant was mainly a second-line treatment after failure of other treatments (macular laser photocoagulation and/or intravitreal injection of anti-VEGF). Three patients were naive of anti-VEGF treatment. Intraocular pressure≥25mmHg was found in 2 patients, and controlled medically. No glaucoma surgery was performed. CONCLUSION: The dexamethasone implant (OZURDEX®) allows an anatomical and functional improvement in patients suffering from vision loss due to DME. In this series, the implant was well tolerated.


Subject(s)
Dexamethasone/administration & dosage , Diabetic Retinopathy/drug therapy , Drug Implants , Macular Edema/drug therapy , Aged , Dexamethasone/adverse effects , Drug Implants/adverse effects , Female , Glucocorticoids/administration & dosage , Glucocorticoids/adverse effects , Humans , Intravitreal Injections , Male , Middle Aged , Retrospective Studies , Treatment Outcome , Visual Acuity/drug effects
12.
Phys Rev Lett ; 117(13): 139901, 2016 Sep 23.
Article in English | MEDLINE | ID: mdl-27715108

ABSTRACT

This corrects the article DOI: 10.1103/PhysRevLett.117.116601.

13.
Phys Rev Lett ; 117(11): 116601, 2016 Sep 09.
Article in English | MEDLINE | ID: mdl-27661707

ABSTRACT

Memory is one of the unique qualities of a glassy system. The relaxation of a glass to equilibrium contains information on the sample's excitation history, an effect often refer to as "aging." We demonstrate that under the right conditions a glass can also possess a different type of memory. We study the conductance relaxation of electron glasses that are fabricated at low temperatures. Remarkably, the dynamics are found to depend not only on the ambient measurement temperature but also on the maximum temperature to which the system was exposed. Hence the system "remembers" its highest temperature. This effect may be qualitatively understood in terms of energy barriers and local minima in configuration space and therefore may be a general property of the glass state.

14.
J Fr Ophtalmol ; 39(4): 370-5, 2016 Apr.
Article in French | MEDLINE | ID: mdl-26850508

ABSTRACT

INTRODUCTION: Pseudoxanthoma elasticum (PXE), a rare hereditary connective tissue disorder, may be complicated by angioid streaks (AS) and choroidal neovascularization (CNV), which may lead to irreversible loss of visual acuity (VA). Here we describe the safety and efficacy of ranibizumab in patients with CNV secondary to PXE. METHODS: A multicenter (n=23), observational study of a retrospective/prospective cohort, performed under real world conditions in France in all patients with CNV secondary to PXE who received at least one ranibizumab injection as of October 2011. The study objectives were to describe the mean annual number and reason for ranibizumab injections since initiation, evolution of best-corrected visual acuity (BCVA by Early Treatment Diabetic Retinopathy Study [ETDRS] letters), and safety. RESULTS: Patients (n=72; 98 eyes) had a mean age of 59.6±8.3years and consisted of 54.2% men. The criterion for retreatment was based mainly on loss of VA, progression of CNV and angiographic leakage. CNV was primarily subfoveal or juxtafoveal (73.4%), and the initial mean VA was 64.6 ETDRS letters. On average, visual acuity of all eyes analyzed was relatively stable during the 2-year follow-up (62.3 letters vs 64.6 letters at the first injection), and 88.6% of eyes maintained VA between -15 and +15 letters or gained over 15 letters. No deaths or new intolerances were described. CONCLUSIONS: These results showed that ranibizumab was able to maintain stable VA in clinical practice for at least 2years in patients with CNV secondary to PXE, and to significantly reduce the frequency of neovascularization relapses, with a limited number of injections. The treatment was well tolerated by the patients.


Subject(s)
Choroidal Neovascularization/drug therapy , Pseudoxanthoma Elasticum/drug therapy , Ranibizumab/therapeutic use , Adult , Aged , Aged, 80 and over , Choroidal Neovascularization/etiology , Cohort Studies , Female , Follow-Up Studies , France , Humans , Male , Middle Aged , Pseudoxanthoma Elasticum/complications , Ranibizumab/adverse effects , Treatment Outcome
15.
J Fr Ophtalmol ; 37(9): 717-21, 2014 Nov.
Article in French | MEDLINE | ID: mdl-25308789

ABSTRACT

INTRODUCTION: DME is the main cause of loss of vision over the course of diabetes. DME incidence is correlated with diabetes duration, high glycemic levels, high blood pressure, and the severity of diabetic retinopathy. To prevent DME, patients need to have access to medical care. In this study, we sought to know whether DME was more severe in Seine-Saint-Denis, a French area, where the poverty is higher than in other french places, and where the number of physicians is lower. PATIENTS AND METHODS: We enrolled patients suffering from DME and treated by ranibizumab intravitreal injections between November 2012 and April 2013. In order to evaluate the severity of DME and the medical management of diabetes of these patients, we collected the following parameters: central macular thickness measured by SD-OCT, best corrected visual acuity, diabetic retinopathy severity, HbA1c, diabetes duration, type of diabetes, insulinotherapy, previous DME treatment and associated diseases. RESULTS: We included 25 type 2 diabetic patients (8 women and 17 men), the mean age was 64±8.1 years. Mean central macular thickness was 523±145µm. The best corrected visual acuity was 45 letters at baseline (counting fingers-70 letters). Twenty-two patients (88%) had a severe non-proliferative diabetic retinopathy or a proliferative diabetic retinopathy. Mean HbA1c was 7.8% (±2.3%). For 23 cases (92%), diabetes was associated with high blood pressure. Sixty-four percent were treated by insulin. Diabetes lasted for 13.1 years at baseline. DISCUSSION AND CONCLUSION: Diabetic patients, in this case series, had a more severe DME regarding macular thickness and visual acuity than patients from large randomized studies found in the literature. This severity could be due to a sub-optimal management of their diabetes. DME may become a tool to identify patients with a limited access to good medical cares.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Diabetic Retinopathy/epidemiology , Macular Edema/drug therapy , Macular Edema/epidemiology , Ranibizumab/therapeutic use , Severity of Illness Index , Aged , Aged, 80 and over , Diabetes Mellitus, Type 2/epidemiology , Female , France/epidemiology , Humans , Male , Middle Aged , Physicians/supply & distribution , Poverty Areas , Visual Acuity
17.
J Fr Ophtalmol ; 36(1): 35-40, 2013 Jan.
Article in French | MEDLINE | ID: mdl-23084436

ABSTRACT

PURPOSE: To determine whether cataract surgery increases macular thickness in diabetic patients without preoperative retinopathy or macular edema. PATIENTS AND METHODS: In a prospective, non-controlled study, we compared preoperative macular thickness as measured by OCT to that measured 3 and 6 months after cataract surgery. RESULTS: Thirty-six eyes of 21 patients (ten men and 11 women) were included in the study from November 2008 to May 2009. Mean foveolar thickness measured preoperatively was 198 µm (± 18.5 µm) compared with 202 µm (±17.2 µm) 3 months postoperatively and 212 µm (± 18.9 µm) 6 months postoperatively. DISCUSSION: In our study, we do not show a significant increase in central foveolar thickness 3 months after cataract surgery; however, we do measure a significant increase at 6 months. This increase in thickness is similar to that found in the literature after cataract surgery in a non-diabetic population. CONCLUSION: Cataract surgery in diabetic patients without preoperative retinopathy does not appear to induce significant macular thickening compared to non-diabetic patients. The period prior to any diabetic retinopathy or maculopathy seems to be the most amenable to cataract surgery when necessary.


Subject(s)
Cataract Extraction/adverse effects , Diabetes Mellitus, Type 2/pathology , Fovea Centralis/pathology , Aged , Cataract/complications , Cataract/epidemiology , Cataract/pathology , Cataract/rehabilitation , Cataract Extraction/rehabilitation , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/surgery , Diabetic Retinopathy/pathology , Female , Follow-Up Studies , Fovea Centralis/surgery , Glycated Hemoglobin/analysis , Humans , Male , Middle Aged , Organ Size , Postoperative Complications/epidemiology , Retrospective Studies , Visual Acuity/physiology
18.
J Fr Ophtalmol ; 34(9): 641-6, 2011 Nov.
Article in French | MEDLINE | ID: mdl-21889816

ABSTRACT

INTRODUCTION: Posterior capsular opacification is the commonest complication of cataract surgery. It is treated with Nd:YAG laser capsulotomy. However, after treatment, cases of cystoid macular edema have been reported. The purpose of this study was to measure the foveal thickness change after Nd:YAG capsulotomy using optical coherence tomography (OCT) in order to clarify the physiopathology of this edema. PATIENTS AND METHODS: A prospective, single-center study was conducted on patients who underwent Nd:YAG laser capsulotomy between May 2008 and November 2009. All patients received the same drug protocol after Nd:YAG capsulotomy (acetazolamide, apraclonidine, and rimexolone). Demographic parameters (age, sex, and medical history), clinical features (visual acuity, intraocular pressure) before and after Nd:YAG laser, and laser complications were analyzed. Central foveal thickness was measured by OCT (Stratus OCT 3, Zeiss). Data were collected before Nd:YAG laser capsulotomy and 1 week, 1 month, and 3 months after capsulotomy. The preoperative and postoperative thicknesses were compared. We used a Student t-test for statistical analysis. RESULTS: Thirty eyes of 26 patients were analyzed. The mean foveal thickness was 209 ± 26 µm before capsulotomy, 213 ± 23 µm, 204 ± 19 µm, 213 ± 23 µm 1 week, 1 month, and 3 months, respectively, after capsulotomy. The foveal thickness did not significantly change during the first 3 months following laser treatment. No complications occurred. DISCUSSION AND CONCLUSION: Macular cystoid edema was a classical complication after Nd:YAG capsulotomy. However, there was no significant increase of macular thickness shortly after Nd:YAG capsulotomy in our study.


Subject(s)
Cataract Extraction/adverse effects , Cataract Extraction/methods , Fovea Centralis/pathology , Lasers, Solid-State/adverse effects , Lasers, Solid-State/therapeutic use , Lens Capsule, Crystalline/surgery , Tomography, Optical Coherence , Adult , Aged , Aged, 80 and over , Cataract/epidemiology , Cataract/pathology , Cataract/rehabilitation , Cataract Extraction/rehabilitation , Cataract Extraction/statistics & numerical data , Female , Humans , Lens Capsule, Crystalline/pathology , Macular Edema/epidemiology , Macular Edema/etiology , Male , Middle Aged , Organ Size , Tomography, Optical Coherence/methods , Visual Acuity
19.
Phys Rev Lett ; 106(18): 186602, 2011 May 06.
Article in English | MEDLINE | ID: mdl-21635115

ABSTRACT

It is shown that the conductance relaxations observed in electrical field effect measurements on granular Al films are the sum of two contributions. One is sensitive to gate voltage changes and gives the already reported anomalous electrical field effect. The other one is independent of the gate voltage history and starts when the films are cooled down to low temperature. Their relative amplitude is strongly thickness-dependent which demonstrates the existence of a finite screening length in our insulating films and allows its quantitative estimate (about 10 nm at 4 K). This metalliclike screening should be taken into account in the electron glass models of disordered insulators.

20.
J Fr Ophtalmol ; 34(2): 127.e1-4, 2011 Feb.
Article in French | MEDLINE | ID: mdl-21131098

ABSTRACT

We present a case report on a young man complaining of transient myopia following a blunt trauma. Clinical and paraclinical (ultrasound) follow-up allowed us to discuss the different physiopathological mechanisms involved. We observed anterior lens displacement, increased lens thickness probably due to lens edema, choroidal detachment, and ciliary body edema. Progression was positive with full regression of the myopia. Ultrasound analysis also underlined an iridocorneal angle closure that could have led to angle-closure glaucoma (preventive peripheric iridotomy was discussed). The spontaneous progression showed spontaneous angle reopening on the main meridians.


Subject(s)
Athletic Injuries/complications , Eye Injuries/complications , Football/injuries , Myopia/etiology , Wounds, Nonpenetrating/complications , Adolescent , Anterior Chamber/injuries , Anterior Chamber/physiopathology , Athletic Injuries/physiopathology , Eye Injuries/physiopathology , Follow-Up Studies , Gonioscopy , Humans , Lens, Crystalline/injuries , Lens, Crystalline/physiopathology , Male , Microscopy, Acoustic , Myopia/physiopathology , Remission, Spontaneous , Tomography, Optical Coherence , Visual Acuity/physiology , Wounds, Nonpenetrating/physiopathology
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