Background: To examine the effect of internal limiting membrane peeling on the inner retinal layers in patients without macular pathological condition. Methods: A prospective nonrandomized trial of patients undergoing pars plana vitrectomy with internal limiting membrane peeling for pathologic condition outside the macula was performed. Optical coherence tomography including macular ganglion cell layer, inner plexiform layer, and peripapillary retinal nerve fiber layer imaging was performed before surgery, 1, 3, and 6 months postoperatively, and at the end of follow-up (ranges between 4 and 17 months). Patients with any macular pathological condition on optical coherence tomography before surgery were excluded. The main outcome measure was change in thickness of the ganglion cell layer and inner plexiform layer. Results: Ten patients who underwent pars plana vitrectomy with internal limiting membrane peeling for macula-on retinal detachment were included in the analysis. The mean age was 55 years, and the mean follow up was 10.8 months. All patients completed at least two postoperative follow-up visits that included an optical coherence tomography as per the protocol (range 2-6 months). There was an immediate reduction in the global (G), inferotemporal, superotemporal, and superior (S) ganglion cell layer thickness at the first follow up as compared with the preoperative state (P = 0.028, P = 0.027, P = 0.026, and P = 0.027 respectively). From the first follow-up visit onward until the final follow-up, the thinning persisted, although there was no further statistically significant thinning. Conclusion: Peeling of the internal limiting membrane causes significant ganglion cell layer thinning in maculae without pathologic condition before surgery. At up to 17 months of follow-up, this effect seems to be immediate and nonprogressive.
Perfluorocarbon liquids (PFCLs) are essential in ophthalmology due to their unique properties, such as higher density than water, inert chemical nature and optical transparency. They serve as crucial tools in retinal detachment surgery, acting as both intraoperative aids and short-term tamponade agents. However, the interactions between PFCLs and the retinal surface are not fully understood, limiting insights into potential complications. This study investigated the interfacial interaction between perfluorodecalin (PFCL) and the retinal surface. The wetting behavior of animal retinas by water and PFCL was analyzed, revealing the water droplet floating phenomenon in PFCL and calculating the critical radius for this effect. The dynamics of water spreading over the retina were examined. A model experiment demonstrated that the tendency of water to float over PFCL, interacting with a hydrophilic surface such as the retina, could create traction and damage the retinal surface. These findings enhance the comprehension of physical processes at the PFCL/retina interface and offer practical insights for improving ophthalmic surgical procedures.
PURPOSE:To report a case of atypical, indolent presentation of scleral buckle infection, caused by Cutibacterium acnes (formerly known as Propionibacterium acnes ). METHODS:Observational case report. RESULTS:A 44-year-old healthy woman with a history of scleral buckling procedure for retinal detachment repair 16 years before presentation was admitted with pain and redness in her left eye for 6 weeks. Conjunctival hyperemia and vascular congestion were noted over the scleral buckle in a circular manner without signs of exposure. After removal of the scleral buckle, culture analysis revealed C. acnes. Systemic amoxicillin was administrated. Over a six-month follow-up, the retina remained attached. CONCLUSION:Cutibacterium acnes , known to be associated with chronic postoperative endophthalmitis after cataract surgery, may also lead to scleral buckle infection with an indolent, chronic course.
Background. We report the case of bilateral, subinternal limiting membrane crystalline deposits in a patient with Terson syndrome, describe the possible pathogenesis, and highlight management. Case Presentation. A 24-year-old male with a history of traumatic massive parenchymal and subdural frontal hemorrhage presented to our clinic seven months after a motor vehicle accident, prolonged hospitalization, and rehabilitation, complaining of decreased vision in both eyes. The Snellen visual acuity was 1/60 in the right eye, and 6/60 in the left eye. Fundus examination showed an organized white vitreous hemorrhage in both eyes with almost no view of the retina. The anterior segments were normal. He underwent a 25-gauge pars plana vitrectomy in both eyes. During the surgery, golden crescent-shaped sediment consisting of small crystals was observed under the internal limiting membrane in both eyes: anterior to the inferior temporal vascular arcade in the right eye and posterior to it in the left eye. Internal limiting membrane (ILM) peeling after staining with ILM-blue dye was performed in the left eye, where the finding involved the macula. One year after the surgery, visual acuity significantly improved to 6/8.5 on the right and 6/6 on the left. Epiretinal membrane formation was observed in the right eye, where ILM peeling was not performed. Conclusion. Subinternal limiting membrane crystalline deposit finding is a rare condition. Consider performing internal limiting membrane peeling and sediment removal in cases with macular involvement. In cases where crystals are concentrated outside of the macula, follow-up may be considered.
Purpose To investigate the features and treatment response in Caucasian patients with polypoidal choroidal vasculopathy (PCV), initially treated with bevacizumab. Methods 45 eyes of 43 treatment-naïve patients with PCV were included in this retrospective study, all uniformly initially treated with three bevacizumab injections monthly. OCT characteristics and clinical parameters were recorded and analyzed at presentation, after the initial 3 bevacizumab injections and at the final follow up period. Results Following 3 monthly bevacizumab injections visual acuity significantly improved with a mean gain of one line of vision. Central macular thickness (CMT) significantly improved from a mean of 402.1 ± 130.8 μm at presentation to 322.0 ± 96.8 μm (p < 0.01). Subretinal fluid, intraretinal fluid and submacular hemorrhage significantly improved. 53% were later switched to aflibercept and showed better response in the central macular thickness in comparison to those in which bevacizumab injections were continued. No correlation was found between the presence of pachyvessels or increased choroidal thickness and the improvement in VA or CMT. Conclusion Fixed first-line treatment with intravitreal bevacizumab monotherapy in non-Asian PCV patients achieves satisfactory visual and anatomical outcomes .
Purpose: This study aimed to compare the risk for post-injection endophthalmitis between different anti-vascular endothelial growth factor (VEGF) agents and syringe preparation techniques. Methods: A retrospective study of anti-VEGF injections performed in 3 large ophthalmology departments between 2013 and 2019 was conducted. Injections were categorized according to the drug and the syringe-filling technique – prefilling by a hospital pharmacy, prefilling by a good manufacturing practice (GMP) pharmacy, self-drawing from the vial by the injecting physician, and use of a prefilled syringe. Cases of endophthalmitis were identified, and their rates were analyzed. Results: A total of 197,402 injections were included, and 53 cases of endophthalmitis were identified (0.027% risk). The risk of endophthalmitis following injections with syringes that were prefilled by GMP pharmacies or the manufacturers was significantly lower than that following injections which were self-drawn by the physician (0.019% vs. 0.055%, p < 0.0001). For ranibizumab, risk of endophthalmitis decreased since it became available in a prefilled syringe (0.054% vs. 0.014%, p = 0.066), bordering on statistical significance. Conclusions: The syringe-filling technique is an important factor determining risk of post-injection endophthalmitis. Use of GMP-grade prefilling by professional pharmacies or the manufacturers significantly reduces this risk and should be the technique of choice for all drugs administered by intravitreal injection.
PURPOSE To evaluate the optical performance and quality of vision of a novel optical design of a new trifocal intraocular lens (IOL) using a proprietary modified algorithm. METHODS In this prospective, non-randomized, single-armed, single-center, open-label study, a total of 20 patients (40 eyes) who were candidates for multifocal lens implantation were recruited for implantation with the multifocal Intensity SL IOL (Hanita Lenses). Evaluation performed at 1 and 7 to 10 days and 1 and 3 months after implantation included corrected and uncorrected distance visual acuities at far, intermediate (80 cm), and near (40 cm). Monocular and binocular visual acuities, defocus curves, and contrast sensitivity were measured and questionnaires for grading subjective visual quality, satisfaction, and visual function were provided. RESULTS Three months postoperatively, monocular uncorrected visual acuity for distance, intermediate, and near averaged 0.03 ± 0.11, 0.09 ± 0.09, and -0.22 ± 0.09 logMAR, respectively (Snellen 20/21.4, 20/24.6, and 20/12). Corrected monocular visual acuity for distance, intermediate, and near averaged -0.07 ± 0.06, 0.03 ± 0.09, and -0.25 ± 0.07 logMAR (20/17, 20/21.4, and 20/11.2), respectively. Binocular corrected visual acuity for distance, intermediate, and near was -0.1 ± 0.06, -0.02 ± 0.09, and -0.28 ± 0.04 logMAR (20/15.8, 20/19, and 20/10.5), respectively. Contrast sensitivity was similar to the normal population in photopic and mesopic conditions. Defocus curves showed that this IOL provided visual acuity of 20/28.9 or better between a defocus of +1.00 and -3.50 diopters. The Visual Function Index-14 questionnaire showed that patients reported high satisfaction. Patients specifically noted good quality of vision at near and intermediate distances. CONCLUSIONS The Intensity SL IOL can provide good quality distance, intermediate, and particularly strong near vision after cataract surgery and independence from spectacles with good patient satisfaction. [J Refract Surg. 2022;38(3):150-157.].
This paper is devoted to the interfacial aspects of the intraocular behavior, migration and distribution of commonly injected ophthalmic drugs in eyes filled with medical-grade 1300 cSt silicone oil used as a retinal tamponade agent. Novel in vitro and ex vivo models were created for studying the physical properties of the retinal surface and interfacial spreading of the ophthalmic drugs over retinas. In vitro model experiments showed that the droplets of all tested drugs sank rapidly in the silicone oil to contact with the plasma-treated glass and then rapidly spread over the glass surface. In the ex vivo model, the migration phase was followed by contact with and rapid spread/absorption by the retinal interface. The wetting behavior of drugs under contact with the glass substrate and retinas was similar. The characteristic timescales of drug spreading, controlled by the viscous dissipation, were close. All tested drugs migrated to the retinal surface and rapidly spread across the retinal surface. This suggests that intravitreal drugs might be used effectively in eyes filled with silicone oil tamponade, as they rapidly migrate to and spread over the retinal surface.
Phosphorylation has been hypothesized to alter the ability of tau protein to bind with microtubules (MT), and pathological level of phosphorylation can incorporate formation of Paired Helical Filaments (PHF) in affected tau. Study of the effect of phosphorylation on different domains of tau (projection domain, microtubule binding sites and N-terminus tail) is important to obtain insight about tau neuropathology. In an earlier study, we have already obtained the mechanical properties and behavior of single tau and dimerized tau and observed tau-MT interaction for normal level of phosphorylation. This study attempts to obtain insights on the effect of phosphorylation on different domains of tau, using molecular dynamics (MD) simulation with the aid of CHARMM force field under high strain rate. It also determines the effect of residue focused phosphorylation on tau-MT interaction and tau accumulation tendency. The results show that for single tau protein, unfolding stiffness does not differ significantly due to phosphorylation, but stretching stiffness can be much higher than the normally phosphorylated protein. For dimerized tau protein, the stretching required to separate the protein forming the dimer is similar for phosphorylation in individual domains but is significantly less in case of phosphorylation in all domains. For tau-MT interaction simulations, it is found that for normal phosphorylation, the tau separation from MT occurs at higher strain for phosphorylation in projection domain and N-terminus tail, and earlier for phosphorylation in all domains altogether than the normal phosphorylation state. The residue focused phosphorylation study also shows that tau separates earlier from MT and shows stronger accumulation tendency at the phosphorylated state, while preserving the highly stretchable and flexible characteristic of tau. This study provides important insight on mechanochemical phenomena relevant to traumatic brain injury (TBI) scenario, where the result of mechanical loading and posttranslational modification as well as conformation decides the mechanical behavior.
Purpose To present updated risk factors, anatomical and visual outcomes and a surgical approach to posteriorly dislocated intraocular lenses (IOL). Methods A retrospective case series review of patients presenting with posteriorly dislocated IOL to the vitreous was performed. All cases were managed surgically with pars plana vitrectomy (PPV) followed by IOL repositioning and refixation or IOL exchange. Clinical characteristics, risk factors for IOL dislocation, visual outcomes and intraoperative and postoperative complications were investigated. Results Forty patients with posteriorly dislocated IOL underwent 3-port PPV and lens retrieval at an average of 6.5 years after cataract surgery. The main causes of IOL dislocation were previous PPV, myopia, pseudoexfoliation syndrome, ocular trauma and recurrent intravitreal injections. The existing IOL was repositioned and secured in 90% of the cases. Visual acuity improved in 34 patients, maintained in 5 and deteriorated in 1. All IOLs were central and stable at final follow-up. Conclusion Posterior intraocular lens dislocation is becoming more prevalent. The main underlying causes found in this series were previous vitrectomy, myopia and recurrent intra-vitreal substance injections. Visual acuity improved in most cases after lens repositioning; however visual outcome is often limited due to associated ocular co-morbidities despite adequate lens position. Despite complete lack of zonular support, a posteriorly dislocated IOL can often be preserved by repositioning and fixation of the lens in the posterior chamber. Pathologies primarily associated with this type of lens malposition include history of vitrectomy, high myopia and multiple intravitreal substance injections.
Interfacial properties of the animal retinas are reported. Wetting of the retina-retinal pigment epitheliumchoroid-sclera tissues of cow, sheep, and pig eyes by water, silicone and castor oil was explored experimentally. Both water and silicone oils demonstrated complete wetting of the retina, regardless of the viscosity of the silicone oil, whereas the castor oil demonstrated a partial wetting regime. Similar wetting regimes were observed for sheep, cow and pig retinas. The intact surface of animal retina was found to be both hydrophilic and oleophilic. Wetting experiments with double sandwich oil/water layers were performed. Water demonstrated stronger affinity to the retina than silicone and castor oils, and eventually replaced the oils at the liquid/retina interface. We conclude that aqueous solutions continuously secreted in the living eye may displace silicone oil from the retinal surface and contribute to retinal re-detachment. Study of dynamics of wetting of the animal retina by water and organic oils is reported. The exponent describing the dynamics of spreading of the castor oil is lower than that predicted by the Tanner law. Castor oil may provide more effective tamponade than silicone oil.
PURPOSE:To determine the effect of varying surface tension and viscosity of fluids used as tamponade in an in vitro eye model of retinal detachment.METHODS:We used an in vitro eye model simulating retinal detachment. Fluids with varying surface tension and identical viscosity, and fluids with varying viscosities and identical surface tension were used as tamponade agents to prevent retinal detachment in the model, to determine which of these properties affects each fluid's effectiveness as a retinal tamponade.RESULTS:The membrane (simulating retinal detachment) changes over time in a vitro eye model were not affected by varying surface tension given constant fluid viscosity. However, membrane changes were proportional to the viscosity of the fluid, given constant surface tension.CONCLUSIONS:The tamponade effect of an intravitreal fluid against retinal detachment may not be related as previously assumed, solely to surface tension, but rather is proportionally related to its viscosity.
PURPOSE:Posterior pole retinal tears occur rarely following blunt trauma. We describe a case of traumatic macular tears, without concurrent peripheral retinal tears or holes.OBSERVATIONS:A 17-year-old patient presented to our emergency unit with blunt ocular trauma and multiple maxillofacial fractures after being assaulted. On examination visual acuity was 20/200 in the left eye with scant vitreous and preretinal hemorrhages. Funduscopic examination revealed multiple choroidal ruptures running concentrically to the optic disc, a subretinal macular hemorrhage, and a large macular tear in the area of the inferior vascular arcade just temporal to the macula. Optical coherence tomography revealed subretinal fluid in the foveal area, choroidal ruptures and a slight elevation of the macular retinal tear margins without subretinal fluid. Laser retinopexy was performed around the macular tear nasally. On follow-up, the retina in the lasered area remained flat, while a shallow retinal detachment had developed temporal to the tear, with a second tear appearing supero-temporally to the macula. Laser retinopexy was not possible due to surrounding subretinal hemorrhage. The clinical course was later complicated by macular detachment, necessitating pars plana vitrectomy with endolaser around the posterior tears and the retinal periphery, and silicone oil injection.CONCLUSIONS:While traumatic macular holes and traumatic macular choroidal ruptures have both been extensively described, posterior pole and macular retinal tears following blunt trauma have rarely been reported. This case illustrates this unusual finding, discussing the possible pathogenic mechanisms and the importance of close follow-up of patients after blunt trauma with appropriate imaging.
BACKGROUND AND OBJECTIVE:Bilateral vision-threatening disease necessitating urgent surgery in both eyes is challenging in vitreoretinal disorders, where surgeries are often longer and higher risk than in other ocular disorders. The authors present a case series of patients undergoing immediate sequential bilateral vitreoretinal surgery (ISBVS) on the same day.PATIENTS AND METHODS:Retrospective case series and literature review. Main outcome measures were surgical indications, systemic diseases, presenting and final visual acuity, and adverse events or complications during or after surgery.RESULTS:During the time period searched, 14 patients underwent ISBVS, without significant adverse events, infections, or complications. Illustrative cases are presented.CONCLUSION:The authors recommend considering ISBVS under certain conditions, such as in patients who are unable to undergo local anesthesia surgery, and in those who definitely require urgent or semi-urgent bilateral vitreoretinal surgery requiring a second general anesthesia in the near future if performed separately, especially in cases where the anesthesia is considered high risk. [Ophthalmic Surg Lasers Imaging Retina. 2020;51:494-498.].
Background: There are several ways to remove silicone oil (SO) from the vitreous cavity. Objectives: To describe a simple, safe and inexpensive method of 2-port SO removal. Method: Medical charts of 33 patients who underwent SO removal combined with cataract extraction were retrospectively reviewed, from a cohort of 119 patients who had silicone oil removal. The primary outcome was the rate of re detachment, secondary outcomes included visual acuity (VA) and intraoperative and postoperative complications. Results: Mean follow-up time was 27.6 months (0.25-147 +/- 33.1), and mean tamponade duration prior to SO removal was 16.77 months (4-51.5 +/- 14.6). The re-detachment rate was 3% (one patient). Postoperatively, seven patients (20%) had epiretinal membrane (ERM), eight patients had posterior capsule opacification (24%), and proliferative vitreoretinopathy (PVR) was diagnosed in two patients (6%). Compared to the mean VA (logarithm of the minimum angle of resolution [LogMARD at the preoperative examination, the mean VA (LogMAR) improved significantly at the last visit when including all ranges of VA (n=32, LogMAR 1.52 vs. 1.05 P = 0.0002 [Student's t-test] and P = 0.001 [Wilcoxon testD. Conclusions: The technique described is fast and simple, keeping the posterior capsule intact in pseudophakic patients, which is advantageous in the event of future re-detachment necessitating SO reinjection. Rates of re-detachment and postoperative ERM and PVR were low. Furthermore, our method does not require the use of a surgical microscope with posterior segment viewing systems, or opening a full disposable vitrectomy set, thus drastically reducing the procedure's cost.
The diagnosis of limited suprachoroidal hemorrhage is subjective – there is no consensus on its definition. Patients with limited suprachoroidal hemorrhage may have only one quadrant involved or multiple quadrants with low-lying choroidal elevation. The term 'massive suprachoroidal hemorrhage' is also subjective and is not constrained by any rigid definition – typically, retinal apposition is present. If the cause of suprachoroidal hemorrhage was a phacoemulsification cataract surgery, the corneal wound will often be in the temporal cornea, and the paracentesis sites should be placed so as to allow optimal access to vitreous incarcerated in the wound in each case. Surgery for suprachoroidal hemorrhage in eyes in which glaucoma valves have previously been implanted poses additional challenges. Once suprachoroidal hemorrhage with extrusion has been recognized, the wound should be tamponaded with the surgeon's or assistant's finger or a Byrne lens if available.
PURPOSE:To present a case of a right eye spontaneous closure of a full thickness macular hole (FTMH), followed several years later by a left eye spontaneous closure of a FTMH, in an otherwise healthy woman.OBSERVATIONS:We show the temporal changes and spontaneous resolution observed with Spectral-Domain Ocular Coherence Tomography (SD-OCT) of a FTMH in the right eye and a FTMH secondary to vitreomacular traction in the left eye of the same patient 5 years later, also with full spontaneous resolution. Following the resolution, SD-OCT demonstrated outer retinal layer disruption recovery and visual acuity improvement in both eyes.CONCLUSIONS AND IMPORTANCE:Spontaneous closure of macular holes is an uncommon event, with most descriptions in the literature being of single cases or very small series, including several reports in patients who have undergone vitrectomy for other causes, or in highly myopic eyes. Bilateral spontaneous closure of macular holes in the same patient is an even more uncommon event, described only once in one patient previously in the literature to our knowledge.
PURPOSE:To report a unique case of pseudo-duplication of the optic disc with maculo-schisis.OBSERVATIONS:A 9-year-old girl presented with decreased vision in the left eye. Her measured visual acuity was 20/50. Dilated fundus examination revealed an optic disc-like lesion with a large crater-like depression, pale color and aberrant retinal vasculature arising from its lower region. Optical coherence tomography (OCT) demonstrated maculo-schisis emerging from the optic disc complex and involving the foveal region. Further pathological findings of cellophane maculopathy with retinal striae was observed at the papillo-macular bundle. On MRI scan there were neither signs of doubling of the optic nerve nor any other optic nerve malformations. The patient underwent 25 Gauge Pars Plana vitrectomy (PPV) with posterior hyaloid peel, ILM peel and gas tamponade with SF6. Eight month post-operatively, a significant reduction in intra-retinal fluids and an improvement in the maculo-schisis magnitude were seen.CONCLUSIONS AND IMPORTANCE:To the best of our knowledge, this is the first reported case of a pseudo-duplication of the optic disc with maculo-schisis treated with PPV.
Purpose: To determine whether higher-viscosity silicone oils offer greater resistance to volume displacement in an in vitro eye model of retinal detachment and could subsequently be expected to generate stronger retinal tamponades in cases of recurrent or complex retinal detachments. Methods: We used an eye model that included a membrane representing the retina. Silicone oils with different viscosities were injected, and oil displacement and resistance were measured. Results: Membrane movement and volume changes in an eye model were proportional to the viscosity of the oil: the lower the viscosity, the faster volume changes and displacement occurred. Conclusions: Our results show that the volume change rate has a linear relationship with oil viscosity. Our findings suggest that in this eye model, silicone oil tamponades the retina against the retinal pigment epithelium mainly through volume displacement and that silicone oil viscosity may play an important role in preventing retinal displacement and in providing tamponade.