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Acta Ophthalmologica Nov 2014To investigate pathomechanisms involved in graft detachment after Descemet's membrane endothelial keratoplasty (DMEK) and its clinical implications.
PURPOSE
To investigate pathomechanisms involved in graft detachment after Descemet's membrane endothelial keratoplasty (DMEK) and its clinical implications.
METHODS
In a prospective case series, 30 eyes with Fuchs' endothelial dystrophy underwent DMEK. Intraoperatively obtained recipients' endothelium-Descemet's membranes (EDMs) were investigated histologically and immunohistochemically. The postoperative donor graft status was categorized as attached or detached. Clinical and morphological parameters were analysed between the study groups.
RESULTS
The detachment rate was 40% (12/30). There was no significant difference in postoperative visual acuity between the groups, but visual recovery was delayed in eyes with initially detached grafts. Gender, age, preoperative central corneal thickness or best corrected visual acuity did not influence the detachment rate. However, separation and disruption of the anterior banded layer (ABL) were frequently observed in patients with graft detachment, and ABL thickness was identified as a significant predictor for graft detachment. The ABL thickness was 2.5 ± 0.9 μm and 3.5 ± 1.6 μm in patients with attached and detached grafts, respectively. Immunohistologically, a deficiency of fibronectin and cytokeratin was observed within the ABL of patients with detached grafts. In contrast, a complete removal of the EDM with residual stromal collagen fragments was observed in patients with adherent grafts.
CONCLUSIONS
Incomplete removal of the EDM, with residual ABL fragments on the recipients' corneal stroma, may be a risk factor for graft detachment after DMEK. The separation and disruption of the ABL might be promoted by a deficiency of matrix proteins, stronger biomechanical properties and a firm adherence to the posterior corneal stroma.
Topics: Aged; Aged, 80 and over; Biomarkers; Corneal Endothelial Cell Loss; Descemet Membrane; Descemet Stripping Endothelial Keratoplasty; Endothelium, Corneal; Female; Fluorescent Antibody Technique, Indirect; Fuchs' Endothelial Dystrophy; Graft Rejection; Humans; Male; Middle Aged; Postoperative Complications; Prospective Studies; Risk Factors; Visual Acuity
PubMed: 24725459
DOI: 10.1111/aos.12419 -
Seminars in Ophthalmology 2014Intraocular silicone oil has several important indications in vitreoretinal surgery, particularly the repair of complicated retinal detachments. Emulsification is a... (Review)
Review
Intraocular silicone oil has several important indications in vitreoretinal surgery, particularly the repair of complicated retinal detachments. Emulsification is a clinically significant complication of using silicone oil tamponade. There are several factors that can promote or prevent silicone oil emulsification after retinal detachment repair, including protein surfactants, contaminants, and shear forces. However, the duration of tamponade remains the most significant one. After emulsification has occurred, keratopathy and glaucoma are the most common complications. However, recent work has shown that emulsification can also affect the retina, optic nerve, and even extraocular structures. Limiting the amount of time the silicone oil remains in the eye is the most important factor in reducing its complications.
Topics: Corneal Diseases; Emulsions; Endotamponade; Glaucoma; Humans; Optic Nerve Diseases; Retinal Detachment; Retinal Diseases; Silicone Oils
PubMed: 25325856
DOI: 10.3109/08820538.2014.962181 -
Frontiers in Neuroscience 2020One may notice a relatively wide range of tactile sensations even when touching the same hard, flat surface in similar ways. Little is known about the reasons for this...
One may notice a relatively wide range of tactile sensations even when touching the same hard, flat surface in similar ways. Little is known about the reasons for this variability, so we decided to investigate how the perceptual intensity of light stickiness relates to the physical interaction between the skin and the surface. We conducted a psychophysical experiment in which nine participants actively pressed their finger on a flat glass plate with a normal force close to 1.5 N and detached it after a few seconds. A custom-designed apparatus recorded the contact force vector and the finger contact area during each interaction as well as pre- and post-trial finger moisture. After detaching their finger, participants judged the stickiness of the glass using a nine-point scale. We explored how sixteen physical variables derived from the recorded data correlate with each other and with the stickiness judgments of each participant. These analyses indicate that stickiness perception mainly depends on the pre-detachment pressing duration, the time taken for the finger to detach, and the impulse in the normal direction after the normal force changes sign; finger-surface adhesion seems to build with pressing time, causing a larger normal impulse during detachment and thus a more intense stickiness sensation. We additionally found a strong between-subjects correlation between maximum real contact area and peak pull-off force, as well as between finger moisture and impulse.
PubMed: 32372893
DOI: 10.3389/fnins.2020.00235 -
La Tunisie Medicale Feb 2023To estimate metamorphopsia prevalence, predictors and etiologies in patients operated for rhegmatogenous retinal detachment (RRD) with detached macula with successful...
AIM
To estimate metamorphopsia prevalence, predictors and etiologies in patients operated for rhegmatogenous retinal detachment (RRD) with detached macula with successful results.
METHODS
Retrospective study including 50 eyes of 50 patients who underwent pars plana vitrectomy for RRD with detached macula with standard silicone oil (SO) tamponade. Patients who had successful surgery with durable anatomic reapplication of the retina after SO removal were included. Patients were examined on day 1, day 7,1 month, and 3 months after surgery. Best corrected visual acuity, Amsler grid, fundus biomicroscopy, Spectral Domain Optical Coherence Tomography (SD-OCT) and fundus auto-fluorescence (FAF) were performed in all patients after surgery. Structural abnormalities such as macular folds, macular epiretinal membrane, cystoid macular edema, and foveal disruption of the ellipsoid layer were observed on SD-OCT. Macular displacement was identified on FAF.
RESULTS
We identified metamorphopsia as post-operative visual impairment in 27 patients among 50 (54%). Clinical assessment found that a delay > 7 days between symptoms and surgery (p < 0.001), more than 2 detached quadrants (p=0.012), and stage C of proliferative vitreoretinopathy (p=0.035) were associated to metamorphopsia. Regarding multimodal imaging findings, only macular folds and macular displacement were significantly correlated with the occurrence of postoperative metamorphopsia (p <0.001).
CONCLUSION
Metamorphopsia is a common complaint after vitrectomy for RRD. Macular rotation and folds would be the main causes after complete and durable reapplication of the retina.
Topics: Humans; Retinal Detachment; Vitrectomy; Prevalence; Retrospective Studies; Vision, Low
PubMed: 37682273
DOI: No ID Found -
Retinal Cases & Brief Reports Jan 2023Persistent fetal vasculature (PFV) may be associated with tractional retinal detachment due to tractional contraction of the fibrovascular stalk. PFV is often thought to...
PURPOSE
Persistent fetal vasculature (PFV) may be associated with tractional retinal detachment due to tractional contraction of the fibrovascular stalk. PFV is often thought to be congenital and non-progressive. A rhegmatogenous component is far less common and is typically identified as a post-operative complication and has not been spontaneously reported. We present five cases illustrating potential progressive changes and complications that may arise in non-operated PFV.
METHODS
A retrospective case series of five patients who presented with progressive retinal detachments from persistent fetal vasculature.
RESULTS
Five unique cases of persistent fetal vasculature with significant progression from time of initial presentation, four of which included development of rhegmatogenous components.
CONCLUSION
Patients with PFV and a seemingly stable tractional detachment should undergo evaluation with a retina specialist for risk stratification and management, as rhegmatogenous detachments may occur due to ocular growth and stretch breaks, and tractional detachments can continue to progress over time.
PubMed: 38166207
DOI: 10.1097/ICB.0000000000001547 -
Indian Journal of Ophthalmology Nov 2023Aggressive retinopathy of prematurity (AROP) is a severe and progressive variant of retinopathy of prematurity (ROP) rapidly forming fibrous tissue extending from the...
INTRODUCTION
Aggressive retinopathy of prematurity (AROP) is a severe and progressive variant of retinopathy of prematurity (ROP) rapidly forming fibrous tissue extending from the disc toward the posterior lens surface progressing to Stage 5 disease without traversing the classical course that includes Stages 1 to 3. Since AROP behaves differently from type 1 ROP, this study was undertaken to evaluate the surgical outcome of AROP-related detachments.
METHODS
Retrospective analysis of data from electronic medical records of babies diagnosed with AROP-related detachments who underwent micro-incision vitrectomy surgery (MIVS) was included. The demographic data, details of primary intervention (laser and/or intravitreal bevacizumab), and surgery were noted. In a subset of patients, surgical intervention was planned early at the onset of fibrovascular tissue.
RESULTS
43 eyes of 26 babies with median birth weight 1175 g and median gestational age of 29 weeks were analyzed. 42/43 eyes underwent primary intervention in form of laser and/or anti-VEGF injection before surgery. 41.8%, 25.5%, and 32.5% eyes progressed to stages 4A, 4B, and 5, respectively, requiring surgical intervention. 66% eyes underwent lensectomy and vitrectomy (LV), and 44% eyes underwent lens sparring vitrectomy (LSV). 58% eyes had attached macula. 44% eyes that had a relatively less vascular diseases had better anatomical outcome (P = 0.019). At final follow-up, 53.4% eyes followed or at least had light fixation, and 77.7% eyes undergoing LSV fixated and/or followed light compared to 33% for LV (P = 0.04).
CONCLUSION
Challenges in AROP include rapid progression to advanced stages of ROP requiring close monitoring and multiple interventions. Surgeries for AROP have a favorable anatomical and functional outcome in 58% and 53%, respectively. Eyes undergoing lens sparing vitrectomy had better visual outcomes.
Topics: Infant, Newborn; Infant; Humans; Retinal Detachment; Retinopathy of Prematurity; Follow-Up Studies; Treatment Outcome; Retrospective Studies; Vitrectomy; Gestational Age
PubMed: 37870006
DOI: 10.4103/IJO.IJO_2999_22 -
American Journal of Ophthalmology Oct 2017To report on the presence of retinal pigment epithelium (RPE) humps in high myopia, and to describe the distinctive features from pathologic RPE detachments and... (Observational Study)
Observational Study
PURPOSE
To report on the presence of retinal pigment epithelium (RPE) humps in high myopia, and to describe the distinctive features from pathologic RPE detachments and choroidal neovascularizations (CNVs).
DESIGN
Retrospective cross-sectional study.
METHODS
Charts and imaging studies of highly myopic patients presenting between September 2015 and February 2017 at a university teaching hospital were consecutively reviewed. All patients underwent spectral-domain optical coherence tomography (OCT). RPE humps were defined as RPE elevations above its physiologic profile, without any evidence of pathologic sub-RPE material. Multimodal imaging was analyzed to assess abnormalities of the RPE and choroid.
RESULTS
One hundred and ninety-five eyes of 101 highly myopic patients were included. RPE humps on structural OCT were identified in 99 out of 195 eyes (estimated prevalence of 50.8%; 43.8%-57.8, 95% confidence intervals). In all eyes, RPE humps corresponded to large choroidal vessels lifting the RPE. Patchy, diffuse, or CNV-related atrophy was more common in eyes with RPE humps (60.6% vs 34.4%; P < .05). The presence of a large choroidal vessel elevating the RPE and the absence of abnormal material between the RPE and the Bruch membrane were the features distinctive from pathologic RPE detachments and CNVs.
DISCUSSION
RPE humps were frequently observed in highly myopic eyes and they resulted from the presence of an underlying large choroidal vessel. They are more likely to appear in highly myopic eyes with advanced choroidal atrophy. To prevent unnecessary treatments, they should be distinguished from pathologic RPE detachments and CNVs.
Topics: Choroid; Choroidal Neovascularization; Cross-Sectional Studies; Female; Fluorescein Angiography; Humans; Male; Middle Aged; Multimodal Imaging; Myopia, Degenerative; Retinal Detachment; Retinal Pigment Epithelium; Retrospective Studies; Tomography, Optical Coherence; Visual Acuity
PubMed: 28734810
DOI: 10.1016/j.ajo.2017.07.013 -
Ophthalmology. Retina Jan 2023
Topics: Humans; Retinal Detachment; Renal Dialysis; Ophthalmologic Surgical Procedures; Scleral Buckling; Retina
PubMed: 36152984
DOI: 10.1016/j.oret.2022.09.003 -
Ophthalmology. Retina May 2023
Topics: Humans; Retinal Detachment; Pigment Epithelium of Eye; Fundus Oculi
PubMed: 36868919
DOI: 10.1016/j.oret.2023.01.013 -
Food Research International (Ottawa,... Jan 2021Staphylococcus aureus is one of the main pathogens contributing to foodborne outbreaks, owing in part to its ability to form biofilms on food-contact surfaces. Cells...
Staphylococcus aureus is one of the main pathogens contributing to foodborne outbreaks, owing in part to its ability to form biofilms on food-contact surfaces. Cells that can detach from mature biofilms are a source for microbial cross-contamination in liquid food systems. The study was to evaluate and compare the resistance of detached-cells of biofilm formed by S. aureus and planktonic cells to Ultra High Pressure Homogenization (UHPH), a non-thermal technology applied in food processing. The results showed that the survival of both detached-cells and planktonic cells was dependent upon the applied pressure ranging from 30,000 PSI to 40,000 PSI, and cycle numbers with 1 and 3. A significant difference in UHPH resistance was observed at pressures of 35,000 PSI to 40,000 PSI whereby planktonic cell numbers were reduced about 2.0 log CFU/mL compared to a 0.5 log CFU/mL reduction of detached-cells. Cell resistance was further evaluated following UHPH by measuring membrane integrity and potential, as well as observing the cells using scanning electron microscopy (SEM). SEM images revealed more scattered exopolysaccharides in the biofilm after UHPH treatment compared to the control. Additionally, UHPH treatment resulted in planktonic cells having a greater shift to smaller cell size and a wider cell size distribution compared with detached-cells; this indicated a higher resistance of detached-cells to UHPH. This finding suggests that although UHPH has great potential application in food sterilization, the resistance of detached-cells cannot be ignored.
Topics: Biofilms; Food Handling; Plankton; Staphylococcus aureus
PubMed: 33509506
DOI: 10.1016/j.foodres.2020.109954