A Novel Surgical Technique for Transscleral Gore-Tex Suture-Assisted Rescue of Dislocated CZ70BD Intraocular Lenses Using 27-Gauge Instrumentation.

PURPOSE: To report a novel technique for refixation of dislocated CZ70BD intraocular lens (IOL). METHODS: Vitrectomy trocars are placed along the horizontal meridian 5 mm apart. A CV-8 Gore-Tex suture is introduced through a bare sclerotomy into the midvitreous cavity. Under chandelier illumination, a 27 G broad platform forceps is threaded through the eyelet of the dislocated CZ70BD IOL. Using another pair of intraocular forceps, the free intraocular end of the Gore-Tex suture is fed to the broad platform forceps and externalized, thus repositioning the IOL. Particular attention is drawn to pass the suture in an over and under configuration to avoid IOL tilt. An identical procedure is repeated for the other eyelet if the IOL is completely dislocated. The 23 gauge or 25 gauge instruments should not be used for this technique because they do not fit loosely through the eyelets of the IOL. RESULTS: Three eyes were successfully operated on using this technique with at least 6 months of follow-up. There was significant improvement in best-corrected visual acuity after the operation. Postoperative IOL centration and alignment were satisfactory. CONCLUSION: The described surgical technique is effective for transscleral Gore-Tex-assisted refixation of dislocated CZ70BD IOL.

ROLE OF OPTICAL COHERENCE TOMOGRAPHY IN MANAGEMENT OF ACUTE POSTERIOR VITREOUS DETACHMENT AND ITS COMPLICATIONS.

PURPOSE: Currently, no consensus exists on the role of optical coherence tomography (OCT) imaging in the setting of acute posterior vitreous detachment (PVD). The authors outline the clinical utility of OCT in the management of acute PVD and its complications. METHODS: Literature review of OCT findings in association with acute PVD and report of illustrative cases. RESULTS: Optical coherence tomography imaging in the setting of acute PVD can provide details of vitreoretinal interface that are difficult to appreciate on biomicroscopy alone including partial PVDs, focal vitreoretinal adhesions and traction, and subclinical macular changes. The presence of vitreous hyperreflective dots on OCT in the premacular space, especially if severe, is highly correlated with the presence of peripheral retinal breaks and development of epiretinal membrane. Advancements in OCT technology, including enhanced vitreous imaging OCT, swept-source OCT, wide-angle OCT, and widefield OCT, allow for increased resolution and expanded field of imaging of the vitreoretinal interface. CONCLUSION: Optical coherence tomography imaging is an emerging standard of care in the setting of patients presenting with new flashes and floaters. The authors highlight the benefits of OCT imaging in patients with acute PVD, which includes recognition of the status of the vitreoretinal interface, assistance in identifying high-risk PVDs, and performance of risk assessment that predict future macular pathologic condition.

27-GAUGE PARS PLANA/PLICATA VITRECTOMY FOR PEDIATRIC VITREORETINAL SURGERY.

PURPOSE: To report on the feasibility of 27-gauge (G) vitrectomy for pediatric patients. METHODS: This study is an international, multicenter, retrospective, interventional case series. Participants were patients 17 years or younger who underwent 27-G vitrectomy for various indications. RESULTS: The records of 56 eyes from 47 patients were reviewed. Mean age was 5.7 ± 5.2 years. Diagnoses included retinopathy of prematurity (Stages 3 with vitreous hemorrhage, 4A, 4B, and 5), Terson's syndrome, traumatic macular hole, posterior capsular opacification, endophthalmitis, and others. Instruments used were the 27-G infusion, 27-G vitreous cutter, 27-G light pipe, and 27-G internal limiting membrane forceps. Instrument bending was noted in one (1.8%) case. There were no cases with intraoperative complications, infusion issues, or postoperative endophthalmitis. There were 67/145 (46%) sclerotomies that required suturing, of which most (51/145) were sutured out of precaution. There were four cases (7.1%) that required conversion to a larger gauge and three cases (5.3%) that developed postoperative hypotony. Mean visual acuity improved from logarithm of the minimum angle of resolution 1.32 (20/420) to 0.72 (20/105), after a mean follow-up of 125.1 days (P = 0.01). Anatomic success was achieved in 96.4% of eyes after a single surgery. CONCLUSION: Twenty-seven-gauge vitrectomy was safe and feasible in selected pediatric vitreoretinopathies. Further studies are warranted to examine indications and outcomes.

AUTOLOGOUS NEUROSENSORY RETINAL TRANSPLANTATION: Bridging the Gap.

PURPOSE: To review the autologous retinal transplantation surgical technique, indications, rationale, and current outcomes of data published to date. METHODS: Review of surgical technique, preoperative and postoperative best-corrected visual acuity, and macular hole (MH) closure rate in studies with at least five eyes. RESULTS: The weighted average macular hole closure rate is 88%, with a MH closure rate ranging from 66.7% to 100%. The weighted average best-corrected visual acuity improved from mean logarithm of the minimum angle of resolution 1.35 (Snellen equivalent of 20/450) preoperatively to mean logarithm of the minimum angle of resolution 1.02 (Snellen equivalent of 20/210) postoperatively. From the largest autologous retinal transplantation case series, 37% of patients gained 3 or more lines of visual acuity after autologous retinal transplantation for primary or refractory MHs and 74% gained 3 or more lines of visual acuity after autologous retinal transplantation for MH-retinal detachments. Functional improvement including negative Watzke-Allen sign and conversion from positive to negative scotoma was reported in large case series. CONCLUSION: Autologous retinal transplantation is a promising technique for closure of large and refractory MHs otherwise difficult to repair with conventional techniques. This technique may allow for replacement of neural tissue in the macula through cell rehabilitation and regeneration through presumed ectopic synaptogenesis, retinal progenitor cell differentiation and integration, and/or retinal progenitor cell material transfer to host neurons.

27-GAUGE SUTURELESS INTRASCLERAL FIXATION OF INTRAOCULAR LENSES WITH HAPTIC FLANGING: Short-Term Clinical Outcomes and a Disinsertion Force Study.

PURPOSE: To determine whether haptic flanging during 27-gauge sutureless intrascleral fixation of intraocular lenses (IOLs) increases IOL stability and to report the short-term clinical outcomes of sutureless intrascleral surgery using 27-gauge trocar cannulas with haptic flanging. METHODS: Retrospective surgical case series using live and cadaveric human eyes. RESULTS: In the cadaveric experiment using five eyes, flanged haptics required more force to dislocate the IOL compared with unflanged haptics (14 ± 4 vs. 3 ± 1 g, P = 0.03). The clinical series included 52 eyes from 52 patients. The average age at the time of surgery was 73 ± 14 years, with a mean follow-up of 27 ± 19 weeks. The most common indication for surgery was IOL dislocation/subluxation (n = 43, 83%). Mean visual acuity improved from 20/140 preoperatively to 20/50 at postoperative Month 1 (P < 0.001). The most common postoperative issue was intraocular pressure elevation (n = 12, 23%). Two patients (4%) needed a reoperation for IOL dislocation. CONCLUSION: Haptic flanging during 27-gauge sutureless intrascleral surgery creates a more stable scleral-fixated IOL compared with the traditional unflanged technique based on a cadaveric human eye study. In addition, this variation of sutureless intrascleral surgery seems safe and effective for patients who require secondary IOLs.

PROGRESSIVE RETINAL DETACHMENT IN INFANTS WITH RETINOPATHY OF PREMATURITY TREATED WITH INTRAVITREAL BEVACIZUMAB OR RANIBIZUMAB.

PURPOSE: Fibrovascular contraction and tractional retinal detachment (TRD) are recognized complications associated with the use of anti-vascular endothelial growth factor agents in vasoproliferative vitreoretinopathies. The authors characterize TRDs that developed after intravitreal bevacizumab or ranibizumab therapy for vascularly active retinopathy of prematurity. METHODS: This is an international, multicenter, interventional, retrospective, case series. Thirty-five eyes from 23 infants were included. Inclusion required anti-vascular endothelial growth factor treatment of Type 1 retinopathy of prematurity with progression to TRD. RESULTS: Mean gestational age was 26 ± 2 weeks, and mean birth weight was 873 ± 341 g. Mean postmenstrual age on the day of injection was 35 ± 2 weeks. Retinal detachment was noted a mean of 70 days (median, 34; range, 4-335) after injection. Eleven percent detached within 1 week, 23% within 2 weeks, and 49% within 4 weeks. The highest stage of retinopathy of prematurity noted was 4A in 29%, 4B in 37%, and 5 in 34% of eyes. Time to RD negatively correlated with postmenstrual age at the time of injection (Rho = -0.54; P < 0.01). Three TRD configurations were observed: 1) conventional peripheral elevated ridge or volcano-shaped Stage 5 detachment, 2) midperipheral detachment with tight circumferential vectors, and 3) very posterior detachment with prepapillary contraction. Full or partial reattachment was achieved with surgical intervention in 86% of eyes. CONCLUSION: Progressive atypical TRD may occur after anti-vascular endothelial growth factor injections for retinopathy of prematurity. The configuration of the detachment varies with the extent of primary retinal vascularization present at the time of treatment.

STRUCTURAL ANALYSIS AND COMPREHENSIVE SURGICAL OUTCOMES OF THE SUTURELESS INTRASCLERAL FIXATION OF SECONDARY INTRAOCULAR LENSES IN HUMAN EYES.

PURPOSE: To describe surgical outcomes and structural characteristics of intraocular lenses (IOLs) implanted with transconjunctival sutureless intrascleral (SIS) fixation in human eyes. DESIGN: Retrospective interventional surgical case series involving live and cadaveric human eyes. METHODS: In this study, we investigated the surgical outcomes and structural anatomy of secondary IOLs implanted with the SIS technique in human eyes. All cases involving SIS IOL fixation performed at a single academic center from January 1, 2012, through July 30, 2016, were reviewed to describe the surgical technique, common indications, clinical outcomes, and the rate of common operative complications. To investigate the structure of SIS-fixated IOLs in vivo, slit-lamp biomicroscopy, ultrasound biomicroscopy, and intraoperative endoscopy were analyzed to describe anatomical outcomes. The primary anatomical outcomes were the optic pupillary centration and location of haptic externalization. Results were correlated with cadaveric human eyes that underwent the SIS-IOL technique. Cadaveric eyes were imaged and analyzed using high-resolution photography for centration, stress measurements at the haptic-optic junction, and qualitative descriptors of IOL optic and haptic position. RESULTS: A total of 122 consecutive patients who underwent IOL placement using SIS technique were included in the study with mean follow-up of 1.52 years (range, 0.4-4.5 years). The majority (75%) of patients received a new 3-piece IOL for primary aphakia or after IOL exchange. The other patients (25%) had a dislocated 3-piece IOL that was rescued using the SIS technique. Preoperative mean Snellen visual acuity was 20/633 (logarithm of the minimum angle of resolution = 1.501). At the final visit, the mean best-corrected visual acuity was 20/83 (logarithm of the minimum angle of resolution = 0.6243) and final mean spherical equivalent was -0.57 diopters. The most common complications were vitreous hemorrhage (22% of eyes), which resolved spontaneously in most cases, and cystoid macular edema. The rates of IOL dislocation, IOL decentration, haptic erosion, IOL tilting, iris capture, and endophthalmitis were low. Intraoperative endoscopy and ultrasound biomicroscopy demonstrated a securely fixated IOL and well-centered optic without iris or ciliary body touch. Structural study of cadaveric eyes confirmed IOL optic and haptic anatomy observed during live human surgery. The ab interno haptic insertion was the anterior pars plana, away from the iris, ciliary processes and ora serrata. The degree of haptic externalization was correlated with the degree of strain on the haptic-optic junction. The angle of the haptic-optic junction in SIS-fixated IOLs (33.97°) was not significantly different compared with overlaid native nonfixated IOL (32.93°) but increased slightly with degree of haptic tip externalization (36.26 and 39.16 for 2 and 3 mm haptic externalizations, respectively). CONCLUSION: In this comprehensive study, we demonstrate the surgical outcomes achieved with SIS fixation of IOLs. Surgical and postoperative complications do occur, albeit at a low rate, and can effectively be managed with excellent anatomical and visual outcomes. The structural and anatomical data in this study may help guide SIS placement and optimize long-term surgical results.

DEXAMETHASONE INTRAVITREAL IMPLANT FOR THE TREATMENT OF RECALCITRANT MACULAR EDEMA AFTER RHEGMATOGENOUS RETINAL DETACHMENT REPAIR.

PURPOSE: To investigate the efficacy of the intravitreal dexamethasone implant as the treatment for recalcitrant macular edema after successful rhegmatogenous retinal detachment repair. METHODS: A retrospective review of the medical records was performed on 17 consecutive patients (17 eyes) with recalcitrant macular edema associated with rhegmatogenous retinal detachment repair who were treated with a single or multiple injections of an intravitreal dexamethasone 0.7-mg implant (Ozurdex; Allergan Inc) at two centers. Main outcomes of the study were change in logarithm of the minimum angle of resolution visual acuity, measurement of central foveal thickness, and macular cube volume as measured by spectral domain optical coherence tomography and frequency of complications. RESULTS: The mean age was 67 years (range, 51-78 years). All 17 patients received previous topical therapy and 12 of them had previous administration of intravitreal triamcinolone with persistence of macular edema. Baseline mean best-corrected visual acuity was 20/100 (logarithm of the minimum angle of resolution 0.75; range, 0.18-1.3 ±0.37) in the affected eyes. There was a statistically significant improvement in best-corrected visual acuity at 1 month (P < 0.001) and 3 months (P = 0.01). Mean baseline central foveal thickness was 505 µm, and mean macular cube volume was 10.62 mm. There was a statistically significant decrease in central foveal thickness and macular cube volume at 1 month (505-290 µm, P = 0.013 and 10.62-9.13 mm, P < 0.0001) and 3 months (P = 0.01). All patients developed recurrence of macular edema at 3 months, which required retreatment. The average number of implants was 4 (range, 1-14). No adverse effects such as retinal detachment or endophthalmitis occurred. Two patients experienced an increase in intraocular pressure that was controlled with topical therapy. CONCLUSION: Macular edema that occurs in eyes after successful repair of rhegmatogenous retinal detachment can be chronic and recalcitrant, and may be successfully and safely treated with the dexamethasone intravitreal implant.

THE CUTTING EDGE OF RETINOPATHY OF PREMATURITY CARE: Expanding the Boundaries of Diagnosis and Treatment.

PURPOSE: To discuss the latest advances and controversies in the diagnosis and care of infants with retinopathy of prematurity (ROP). METHODS: Literature review. RESULTS: Retinopathy of prematurity remains a major global issue. Industrialized nations now treat profoundly premature infants with posterior and aggressive disease, and middle-income nations are experiencing ROP epidemics. Remote digital imaging may address the decreasing ratio of ROP providers to premature infants, in addition to improving patient care. Widefield angiography, optical coherence tomography, and the Wnt signaling pathway have provided new insights into ROP pathogenesis. Anti-vascular endothelial growth factor treatment is increasing in popularity, but the dearth of information to guide dosing, unpredictable reactivation, persistent vascular abnormalities, the "crunch" phenomenon, and the presently unknown effects of systemic vascular endothelial growth factor suppression remain issues to continue investigating. Neurodevelopmental delay has been raised as a potential consequence, but the evidence currently is weak. Vitrectomy is the treatment of choice for Stages 4 and 5. Illumination techniques, ab interno incisions, plasmin-assisted vitrectomy, staged surgery in the interest of corneal clearing for advanced Stage 5, and immediate sequential bilateral vitreoretinal surgery, are useful techniques. CONCLUSION: We are making progress in ROP management. Our goal as clinicians is to continue expanding the boundaries of our abilities to keep this blinding disease in check globally.

A Review of Novel Anesthetic Technique for Vitreoretinal Surgery.

BACKGROUND AND OBJECTIVE: Currently, there is no standardized formulation of intravenous anesthetic that exists for vitreoretinal surgery. We describe a novel anesthetic protocol for vitreoretinal surgery that is safe and effective for patients and surgeons alike. STUDY DESIGN: Review the current challenges to vitreoretinal anesthetic technique and descriptive overview outlining the proposed anesthetic protocol and associated experience with technique. RESULTS: The proposed anesthetic technique utilizes a sub-tenon peribulbar block with a continuous propofol infusion. A low dosage continuous propofol infusion provides patients with profound anxiolysis and relaxation while maintaining wakefulness. Fentanyl can be additionally titrated for patients that report symptoms of pain or increased respiratory rate. CONCLUSION: A low dose propofol infusion in combination with sub-tenon peribulbar block and judicious use of fentanyl provide an ideal operative condition for ambulatory vitreoretinal surgery. [Ophthalmic Surg Lasers Imaging Retina 2023;54:429-431.].

INTRAOCULAR LENS IMBRICATION FOR RECURRENT PUPILLARY CAPTURE AFTER SUTURELESS INTRASCLERAL FIXATION.

PURPOSE: To demonstrate a novel surgical technique (intraocular lens imbrication) for persistent postoperative pupillary capture after sutureless scleral intraocular lens fixation. METHODS: Case report and supplemental digital content demonstrating salient steps of a novel surgical technique. RESULTS: The patient did not suffer any further episodes of pupillary capture after intraocular lens imbrication with aforementioned surgical technique five months after the procedure. Postoperative best-corrected visual acuities were 20/40 in both eyes. CONCLUSION: Intraocular lens imbrication is an effective method to address persistent postoperative pupillary capture after sutureless scleral intraocular lens fixation.

H-ferritin is the major source of iron for oligodendrocytes.

There is a critical relationship between oligodendrocyte development, myelin production, and iron bioavailability. Iron deficiency leads to hypomyelination both in humans and animal models, and the neurological sequelae of hypomyelination are significant. Therefore, understanding molecular mechanisms of iron import into oligodendrocytes is necessary for devising effective strategies for iron supplementation. Although transferrin has been considered as an essential component of oligodendrocyte media in culture, oligodendrocytes in vivo lack transferrin receptors. We have established that receptors for H-ferritin (HF) exist on cells of oligodendroglial lineage and that uptake of extracellular HF by oligodendrocyte progenitors is via receptor mediated endocytosis. These data strongly argue that ferritin is a major source of iron for oligodendrocytes. In this study, we demonstrate that media deficient in transferrin results in loss of viability of oligodendrocyte progenitors in culture. Cell loss could be prevented by supplementing the media with HF. Moreover, the addition of extracellular HF stimulates development of oligodendrocyte progenitor cells (OPCs) by increasing expression of myelin basic protein (MBP) and olig2 proteins without increasing their proliferation. The effect of HF on the OPCs could be mimicked by addition of membrane permeable 3,5,5-trimethylhexanoyl ferrocene (TMH-Fe) as an iron source to the media, but not membrane-impermeable ferric ammonium citrate. Overall, therefore, our results demonstrate the importance of iron for OPCs viability and differentiation and identify extracellular HF as a critical source of iron for oligodendrocytes. Given that ferritin receptors, but not transferrin receptors can be demonstrated on oligodendrocytes in vivo, the delivery of iron to oligodendrocytes via ferritin may be the more biological relevant delivery system.

CONGENITAL TOXOPLASMOSIS ASSOCIATED WITH TRACTIONAL RETINAL DETACHMENT.

PURPOSE: We report a case of congenital toxoplasmosis associated with retinal detachment. METHODS: A 9-month-old white boy presented a unilateral tractional retina detachment associated with congenital toxoplasmosis retinochoroiditis. RESULTS: The diagnosis is supported by positive IgG (>400) for toxoplasmosis and intracranial calcification on magnetic resonance imaging, along with positive family history of Toxoplasma infection in the mother. CONCLUSION: Tractional retinal detachment is an infrequent and unconventional presentation of congenital Toxoplasma infection. Inflammatory interference with normal sequence of vitreous development may explain pathogenesis of tractional retinal detachments in the setting of congenital ocular toxoplasmosis.

Combination Antivascular Endothelial Growth Factor and Modified Panretinal Photocoagulation in Management of Proliferative Diabetic Retinopathy.

Purpose: This work evaluates the effects of combined intravitreal antivascular endothelial growth factor (anti-VEGF) and modified panretinal photocoagulation (PRP) for management of proliferative diabetic retinopathy (PDR). Methods: This retrospective case series included 37 eyes of 33 patients with high-risk PDR. Anti-VEGF injections (≥ 2) were followed by modified, midperipheral PRP performed in 2 or more sessions. Visual and anatomic outcomes were tracked for 1 year after treatment. Regression analysis was performed for factors predictive of final outcomes. Results: Mean visual acuity (VA) at initial and final visit were 20/50 and 20/40 (P = .22), respectively, over a mean follow-up duration of 341.4 days. Central foveal thickness decreased from 321.8 µm to 258.6 µm (P = .01). Resolution of PDR was achieved in 94.6% of eyes, with 5.4% of eyes requiring additional anti-VEGF for persistent neovascularization. Final VA was significantly associated with baseline VA, VA at 1 month, and any adverse anatomical events. Treatment noncompliance was present in 24.3%; compliance decreased with increasing medical comorbidities, but was not significantly associated with final VA. Conclusions: Combination of anti-VEGF and modified PRP preserved VA and yielded PDR regression in the majority of eyes. This combination provides rapid PDR regression with anti-VEGF while achieving durable disease suppression in this real-world cohort without traditional PRP.

Oligodendrocytes and myelination: the role of iron.

Iron is an essential trophic factor that is required for oxygen consumption and ATP production. Thus it plays a key role in vital cell functions. Although the brain has a relatively high rate of oxygen consumption compared to other organs, oligodendrocytes are the principal cells in the CNS that stain for iron under normal conditions. The importance of iron in myelin production has been demonstrated by studies showing that decreased availability of iron in the diet is associated with hypomyelination. The timing of iron delivery to oligodendrocytes during development is also important because hypomyelination and the associated neurological sequelae persist long after the systemic iron deficiency has been corrected. Therefore, identifying the molecular roles of iron in oligodendrocyte development and myelin production, and the mechanisms and timing of iron acquisitions are important prerequisites to developing effective therapies for dysmyelinating disorders. It is the purpose of this review to give a comprehensive overview of the existing literature on role of iron in oligodendrocytes and the mechanisms of iron acquisition and intracellular handling.